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Message-ID: <CAAhV-H5SO8_ufaCw3BL-20D6uuUBRO35uqA27B1AFm97LZtLHQ@mail.gmail.com>
Date: Wed, 29 Sep 2021 11:24:42 +0800
From: Huacai Chen <chenhuacai@...il.com>
To: Ard Biesheuvel <ardb@...nel.org>
Cc: Huacai Chen <chenhuacai@...ngson.cn>,
Arnd Bergmann <arnd@...db.de>,
Andy Lutomirski <luto@...nel.org>,
Thomas Gleixner <tglx@...utronix.de>,
Peter Zijlstra <peterz@...radead.org>,
Andrew Morton <akpm@...ux-foundation.org>,
David Airlie <airlied@...ux.ie>,
Jonathan Corbet <corbet@....net>,
Linus Torvalds <torvalds@...ux-foundation.org>,
linux-arch <linux-arch@...r.kernel.org>,
Linux Doc Mailing List <linux-doc@...r.kernel.org>,
Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
Xuefeng Li <lixuefeng@...ngson.cn>,
Yanteng Si <siyanteng@...ngson.cn>,
Jiaxun Yang <jiaxun.yang@...goat.com>,
linux-efi <linux-efi@...r.kernel.org>
Subject: Re: [PATCH V4 09/22] LoongArch: Add boot and setup routines
Hi, Ard,
On Mon, Sep 27, 2021 at 2:53 PM Ard Biesheuvel <ardb@...nel.org> wrote:
>
> On Mon, 27 Sept 2021 at 08:49, Huacai Chen <chenhuacai@...ngson.cn> wrote:
> >
> > This patch adds basic boot, setup and reset routines for LoongArch.
> > LoongArch uses UEFI-based firmware and uses ACPI as the boot protocol.
> >
> > Now the boot information passed to kernel is like this:
> > 1, kernel get a0, a1 and a2 from bootloader.
> > 2, a0 is "argc", a1 is "argc", so "cmdline" comes from a0/a1.
> > 3, a2 is "envrion", which is a pointer to a "struct bootparamsinterface"
> > 4, "struct bootparamsinterface" include a "systemtable" pointer, whose
> > type is "efi_system_table_t". Most information, include ACPI tables,
> > come from here.
> >
>
> Could you please quote the relevant sections of the UEFI and ACPI
> specifications where this boot protocol is described?
There is no UEFI/ACPI spec. sections to describe this. Maybe I misused
the "boot protocol" terminology here, we use UEFI firmware to load the
elf format kernel (not efistub), the above just describe how to pass
information to the kernel.
Huacai
>
> > Cc: Ard Biesheuvel <ardb@...nel.org>
> > Cc: linux-efi@...r.kernel.org
> > Signed-off-by: Huacai Chen <chenhuacai@...ngson.cn>
> > ---
> > arch/loongarch/include/asm/acenv.h | 17 +
> > arch/loongarch/include/asm/acpi.h | 37 ++
> > arch/loongarch/include/asm/boot_param.h | 91 +++++
> > arch/loongarch/include/asm/bootinfo.h | 33 ++
> > arch/loongarch/include/asm/dmi.h | 24 ++
> > arch/loongarch/include/asm/efi.h | 32 ++
> > arch/loongarch/include/asm/fw.h | 18 +
> > arch/loongarch/include/asm/reboot.h | 10 +
> > arch/loongarch/include/asm/setup.h | 21 ++
> > arch/loongarch/kernel/acpi.c | 324 ++++++++++++++++
> > arch/loongarch/kernel/cacheinfo.c | 122 ++++++
> > arch/loongarch/kernel/cmdline.c | 28 ++
> > arch/loongarch/kernel/cpu-probe.c | 301 +++++++++++++++
> > arch/loongarch/kernel/efi.c | 95 +++++
> > arch/loongarch/kernel/env.c | 170 +++++++++
> > arch/loongarch/kernel/head.S | 72 ++++
> > arch/loongarch/kernel/mem.c | 83 +++++
> > arch/loongarch/kernel/reset.c | 90 +++++
> > arch/loongarch/kernel/setup.c | 469 ++++++++++++++++++++++++
> > arch/loongarch/kernel/time.c | 237 ++++++++++++
> > arch/loongarch/kernel/topology.c | 13 +
> > 21 files changed, 2287 insertions(+)
> > create mode 100644 arch/loongarch/include/asm/acenv.h
> > create mode 100644 arch/loongarch/include/asm/acpi.h
> > create mode 100644 arch/loongarch/include/asm/boot_param.h
> > create mode 100644 arch/loongarch/include/asm/bootinfo.h
> > create mode 100644 arch/loongarch/include/asm/dmi.h
> > create mode 100644 arch/loongarch/include/asm/efi.h
> > create mode 100644 arch/loongarch/include/asm/fw.h
> > create mode 100644 arch/loongarch/include/asm/reboot.h
> > create mode 100644 arch/loongarch/include/asm/setup.h
> > create mode 100644 arch/loongarch/kernel/acpi.c
> > create mode 100644 arch/loongarch/kernel/cacheinfo.c
> > create mode 100644 arch/loongarch/kernel/cmdline.c
> > create mode 100644 arch/loongarch/kernel/cpu-probe.c
> > create mode 100644 arch/loongarch/kernel/efi.c
> > create mode 100644 arch/loongarch/kernel/env.c
> > create mode 100644 arch/loongarch/kernel/head.S
> > create mode 100644 arch/loongarch/kernel/mem.c
> > create mode 100644 arch/loongarch/kernel/reset.c
> > create mode 100644 arch/loongarch/kernel/setup.c
> > create mode 100644 arch/loongarch/kernel/time.c
> > create mode 100644 arch/loongarch/kernel/topology.c
> >
> > diff --git a/arch/loongarch/include/asm/acenv.h b/arch/loongarch/include/asm/acenv.h
> > new file mode 100644
> > index 000000000000..d1f41fbc9070
> > --- /dev/null
> > +++ b/arch/loongarch/include/asm/acenv.h
> > @@ -0,0 +1,17 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/*
> > + * LoongArch specific ACPICA environments and implementation
> > + *
> > + * Author: Jianmin Lv <lvjianmin@...ngson.cn>
> > + * Huacai Chen <chenhuacai@...ngson.cn>
> > + * Copyright (C) 2020-2021 Loongson Technology Corporation Limited
> > + */
> > +
> > +#ifndef _ASM_LOONGARCH_ACENV_H
> > +#define _ASM_LOONGARCH_ACENV_H
> > +
> > +/* The head file is required by ACPI core, but we have nothing to fill
> > + * it now, update it later when needed.
> > + */
> > +
> > +#endif /* _ASM_LOONGARCH_ACENV_H */
> > diff --git a/arch/loongarch/include/asm/acpi.h b/arch/loongarch/include/asm/acpi.h
> > new file mode 100644
> > index 000000000000..29e2214d5901
> > --- /dev/null
> > +++ b/arch/loongarch/include/asm/acpi.h
> > @@ -0,0 +1,37 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/*
> > + * Author: Jianmin Lv <lvjianmin@...ngson.cn>
> > + * Huacai Chen <chenhuacai@...ngson.cn>
> > + * Copyright (C) 2020-2021 Loongson Technology Corporation Limited
> > + */
> > +
> > +#ifndef _ASM_LOONGARCH_ACPI_H
> > +#define _ASM_LOONGARCH_ACPI_H
> > +
> > +#ifdef CONFIG_ACPI
> > +extern int acpi_strict;
> > +extern int acpi_disabled;
> > +extern int acpi_pci_disabled;
> > +extern int acpi_noirq;
> > +
> > +#define acpi_os_ioremap ioremap
> > +
> > +static inline void disable_acpi(void)
> > +{
> > + acpi_disabled = 1;
> > + acpi_pci_disabled = 1;
> > + acpi_noirq = 1;
> > +}
> > +
> > +static inline bool acpi_has_cpu_in_madt(void)
> > +{
> > + return true;
> > +}
> > +
> > +extern struct list_head acpi_wakeup_device_list;
> > +
> > +#endif /* !CONFIG_ACPI */
> > +
> > +#define ACPI_TABLE_UPGRADE_MAX_PHYS (max_low_pfn << PAGE_SHIFT)
> > +
> > +#endif /* _ASM_LOONGARCH_ACPI_H */
> > diff --git a/arch/loongarch/include/asm/boot_param.h b/arch/loongarch/include/asm/boot_param.h
> > new file mode 100644
> > index 000000000000..f515431d838b
> > --- /dev/null
> > +++ b/arch/loongarch/include/asm/boot_param.h
> > @@ -0,0 +1,91 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +#ifndef __ASM_BOOT_PARAM_H_
> > +#define __ASM_BOOT_PARAM_H_
> > +
> > +#ifdef CONFIG_VT
> > +#include <linux/screen_info.h>
> > +#endif
> > +
> > +#define ADDRESS_TYPE_SYSRAM 1
> > +#define ADDRESS_TYPE_RESERVED 2
> > +#define ADDRESS_TYPE_ACPI 3
> > +#define ADDRESS_TYPE_NVS 4
> > +#define ADDRESS_TYPE_PMEM 5
> > +
> > +#define LOONGSON3_BOOT_MEM_MAP_MAX 128
> > +
> > +#define LOONGSON_EFIBOOT_SIGNATURE "BPI"
> > +#define LOONGSON_MEM_LINKLIST "MEM"
> > +#define LOONGSON_VBIOS_LINKLIST "VBIOS"
> > +#define LOONGSON_SCREENINFO_LINKLIST "SINFO"
> > +
> > +/* Values for Version BPI */
> > +enum bpi_version {
> > + BPI_VERSION_V1 = 1000, /* Signature="BPI01000" */
> > + BPI_VERSION_V2 = 1001, /* Signature="BPI01001" */
> > +};
> > +
> > +/* Flags in bootparamsinterface */
> > +#define BPI_FLAGS_UEFI_SUPPORTED BIT(0)
> > +
> > +struct _extention_list_hdr {
> > + u64 signature;
> > + u32 length;
> > + u8 revision;
> > + u8 checksum;
> > + struct _extention_list_hdr *next;
> > +} __packed;
> > +
> > +struct bootparamsinterface {
> > + u64 signature; /* {"B", "P", "I", "0", "1", ... } */
> > + void *systemtable;
> > + struct _extention_list_hdr *extlist;
> > + u64 flags;
> > +} __packed;
> > +
> > +struct loongsonlist_mem_map {
> > + struct _extention_list_hdr header; /* {"M", "E", "M"} */
> > + u8 map_count;
> > + struct loongson_mem_map {
> > + u32 mem_type;
> > + u64 mem_start;
> > + u64 mem_size;
> > + } __packed map[LOONGSON3_BOOT_MEM_MAP_MAX];
> > +} __packed;
> > +
> > +struct loongsonlist_vbios {
> > + struct _extention_list_hdr header; /* {"V", "B", "I", "O", "S"} */
> > + u64 vbios_addr;
> > +} __packed;
> > +
> > +struct loongsonlist_screeninfo {
> > + struct _extention_list_hdr header; /* {"S", "I", "N", "F", "O"} */
> > + struct screen_info si;
> > +} __packed;
> > +
> > +struct loongson_board_info {
> > + int bios_size;
> > + char *bios_vendor;
> > + char *bios_version;
> > + char *bios_release_date;
> > + char *board_name;
> > + char *board_vendor;
> > +};
> > +
> > +struct loongson_system_configuration {
> > + int bpi_ver;
> > + int nr_cpus;
> > + int nr_nodes;
> > + int nr_io_pics;
> > + int boot_cpu_id;
> > + int cores_per_node;
> > + int cores_per_package;
> > + char *cpuname;
> > + u64 vgabios_addr;
> > +};
> > +
> > +extern struct loongson_board_info b_info;
> > +extern struct bootparamsinterface *efi_bp;
> > +extern struct loongsonlist_mem_map *loongson_mem_map;
> > +extern struct loongson_system_configuration loongson_sysconf;
> > +#endif
> > diff --git a/arch/loongarch/include/asm/bootinfo.h b/arch/loongarch/include/asm/bootinfo.h
> > new file mode 100644
> > index 000000000000..41838633d1aa
> > --- /dev/null
> > +++ b/arch/loongarch/include/asm/bootinfo.h
> > @@ -0,0 +1,33 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/*
> > + * Copyright (C) 2020-2021 Loongson Technology Corporation Limited
> > + */
> > +#ifndef _ASM_BOOTINFO_H
> > +#define _ASM_BOOTINFO_H
> > +
> > +#include <linux/types.h>
> > +#include <asm/setup.h>
> > +
> > +const char *get_system_type(void);
> > +
> > +extern void early_memblock_init(void);
> > +extern void detect_memory_region(phys_addr_t start, phys_addr_t sz_min, phys_addr_t sz_max);
> > +
> > +extern void early_init(void);
> > +extern void platform_init(void);
> > +
> > +extern void free_init_pages(const char *what, unsigned long begin, unsigned long end);
> > +
> > +/*
> > + * Initial kernel command line, usually setup by fw_init_cmdline()
> > + */
> > +extern char arcs_cmdline[COMMAND_LINE_SIZE];
> > +
> > +/*
> > + * Registers a0, a1, a3 and a4 as passed to the kernel entry by firmware
> > + */
> > +extern unsigned long fw_arg0, fw_arg1, fw_arg2, fw_arg3;
> > +
> > +extern unsigned long initrd_start, initrd_end;
> > +
> > +#endif /* _ASM_BOOTINFO_H */
> > diff --git a/arch/loongarch/include/asm/dmi.h b/arch/loongarch/include/asm/dmi.h
> > new file mode 100644
> > index 000000000000..fbe98f0e56e0
> > --- /dev/null
> > +++ b/arch/loongarch/include/asm/dmi.h
> > @@ -0,0 +1,24 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/*
> > + * Copyright (C) 2020-2021 Loongson Technology Corporation Limited
> > + */
> > +#ifndef _ASM_DMI_H
> > +#define _ASM_DMI_H
> > +
> > +#include <linux/io.h>
> > +#include <linux/memblock.h>
> > +
> > +#define dmi_early_remap(x, l) dmi_remap(x, l)
> > +#define dmi_early_unmap(x, l) dmi_unmap(x)
> > +#define dmi_alloc(l) memblock_alloc_low(l, PAGE_SIZE)
> > +
> > +static inline void *dmi_remap(u64 phys_addr, unsigned long size)
> > +{
> > + return ((void *)TO_CAC(phys_addr));
> > +}
> > +
> > +static inline void dmi_unmap(void *addr)
> > +{
> > +}
> > +
> > +#endif /* _ASM_DMI_H */
> > diff --git a/arch/loongarch/include/asm/efi.h b/arch/loongarch/include/asm/efi.h
> > new file mode 100644
> > index 000000000000..90e8e35d7f4b
> > --- /dev/null
> > +++ b/arch/loongarch/include/asm/efi.h
> > @@ -0,0 +1,32 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/*
> > + * Copyright (C) 2020-2021 Loongson Technology Corporation Limited
> > + */
> > +#ifndef _ASM_LOONGARCH_EFI_H
> > +#define _ASM_LOONGARCH_EFI_H
> > +
> > +#include <linux/efi.h>
> > +
> > +extern void __init efi_init(void);
> > +extern void __init efi_runtime_init(void);
> > +extern void efifb_setup_from_dmi(struct screen_info *si, const char *opt);
> > +
> > +#define ARCH_EFI_IRQ_FLAGS_MASK 0x00000001 /*bit0: CP0 Status.IE*/
> > +
> > +#define arch_efi_call_virt_setup() \
> > +({ \
> > +})
> > +
> > +#define arch_efi_call_virt(p, f, args...) \
> > +({ \
> > + efi_##f##_t * __f; \
> > + __f = p->f; \
> > + __f(args); \
> > +})
> > +
> > +#define arch_efi_call_virt_teardown() \
> > +({ \
> > +})
> > +
> > +
> > +#endif /* _ASM_LOONGARCH_EFI_H */
> > diff --git a/arch/loongarch/include/asm/fw.h b/arch/loongarch/include/asm/fw.h
> > new file mode 100644
> > index 000000000000..8a0e8e7c625f
> > --- /dev/null
> > +++ b/arch/loongarch/include/asm/fw.h
> > @@ -0,0 +1,18 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/*
> > + * Copyright (C) 2020-2021 Loongson Technology Corporation Limited
> > + */
> > +#ifndef __ASM_FW_H_
> > +#define __ASM_FW_H_
> > +
> > +#include <asm/bootinfo.h>
> > +
> > +extern int fw_argc;
> > +extern long *_fw_argv, *_fw_envp;
> > +
> > +#define fw_argv(index) ((char *)(long)_fw_argv[(index)])
> > +#define fw_envp(index) ((char *)(long)_fw_envp[(index)])
> > +
> > +extern void fw_init_cmdline(void);
> > +
> > +#endif /* __ASM_FW_H_ */
> > diff --git a/arch/loongarch/include/asm/reboot.h b/arch/loongarch/include/asm/reboot.h
> > new file mode 100644
> > index 000000000000..0e96b0f42993
> > --- /dev/null
> > +++ b/arch/loongarch/include/asm/reboot.h
> > @@ -0,0 +1,10 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/*
> > + * Copyright (C) 2020-2021 Loongson Technology Corporation Limited
> > + */
> > +#ifndef _ASM_REBOOT_H
> > +#define _ASM_REBOOT_H
> > +
> > +extern void (*pm_restart)(void);
> > +
> > +#endif /* _ASM_REBOOT_H */
> > diff --git a/arch/loongarch/include/asm/setup.h b/arch/loongarch/include/asm/setup.h
> > new file mode 100644
> > index 000000000000..fc1fb741b4da
> > --- /dev/null
> > +++ b/arch/loongarch/include/asm/setup.h
> > @@ -0,0 +1,21 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/*
> > + * Copyright (C) 2020-2021 Loongson Technology Corporation Limited
> > + */
> > +
> > +#ifndef _LOONGARCH_SETUP_H
> > +#define _LOONGARCH_SETUP_H
> > +
> > +#include <linux/types.h>
> > +#include <uapi/asm/setup.h>
> > +
> > +#define VECSIZE 0x200
> > +
> > +extern unsigned long eentry;
> > +extern unsigned long tlbrentry;
> > +extern void cpu_cache_init(void);
> > +extern void per_cpu_trap_init(int cpu);
> > +extern void set_handler(unsigned long offset, void *addr, unsigned long len);
> > +extern void set_merr_handler(unsigned long offset, void *addr, unsigned long len);
> > +
> > +#endif /* __SETUP_H */
> > diff --git a/arch/loongarch/kernel/acpi.c b/arch/loongarch/kernel/acpi.c
> > new file mode 100644
> > index 000000000000..3f77c937e9ad
> > --- /dev/null
> > +++ b/arch/loongarch/kernel/acpi.c
> > @@ -0,0 +1,324 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * acpi.c - Architecture-Specific Low-Level ACPI Boot Support
> > + *
> > + * Author: Jianmin Lv <lvjianmin@...ngson.cn>
> > + * Huacai Chen <chenhuacai@...ngson.cn>
> > + * Copyright (C) 2020-2021 Loongson Technology Corporation Limited
> > + */
> > +
> > +#include <linux/init.h>
> > +#include <linux/acpi.h>
> > +#include <linux/irq.h>
> > +#include <linux/irqdomain.h>
> > +#include <linux/memblock.h>
> > +#include <linux/serial_core.h>
> > +#include <asm/io.h>
> > +#include <asm/loongson.h>
> > +
> > +int acpi_disabled;
> > +EXPORT_SYMBOL(acpi_disabled);
> > +int acpi_noirq;
> > +int acpi_pci_disabled;
> > +EXPORT_SYMBOL(acpi_pci_disabled);
> > +int acpi_strict = 1; /* We have no workarounds on LoongArch */
> > +int num_processors;
> > +int disabled_cpus;
> > +enum acpi_irq_model_id acpi_irq_model = ACPI_IRQ_MODEL_PLATFORM;
> > +
> > +u64 acpi_saved_sp;
> > +
> > +#define MAX_CORE_PIC 256
> > +
> > +#define PREFIX "ACPI: "
> > +
> > +/*
> > + * Following __acpi_xx functions should be implemented for sepecific cpu.
> > + */
> > +int acpi_gsi_to_irq(u32 gsi, unsigned int *irqp)
> > +{
> > + if (irqp != NULL)
> > + *irqp = acpi_register_gsi(NULL, gsi, -1, -1);
> > + return 0;
> > +}
> > +EXPORT_SYMBOL_GPL(acpi_gsi_to_irq);
> > +
> > +int acpi_isa_irq_to_gsi(unsigned int isa_irq, u32 *gsi)
> > +{
> > + if (gsi)
> > + *gsi = isa_irq;
> > + return 0;
> > +}
> > +
> > +/*
> > + * success: return IRQ number (>=0)
> > + * failure: return < 0
> > + */
> > +int acpi_register_gsi(struct device *dev, u32 gsi, int trigger, int polarity)
> > +{
> > + int id, hwirq;
> > + struct irq_domain *domain;
> > + struct irq_fwspec fwspec;
> > +
> > + switch (gsi) {
> > + case GSI_MIN_CPU_IRQ ... GSI_MAX_CPU_IRQ:
> > + hwirq = gsi - GSI_MIN_CPU_IRQ;
> > + return irq_create_mapping(liointc_domain, hwirq);
> > +
> > + case GSI_MIN_PCH_IRQ ... GSI_MAX_PCH_IRQ:
> > + id = find_pch_pic(gsi);
> > + if (id < 0)
> > + return -1;
> > +
> > + domain = pch_pic_domain[id];
> > + if (!domain)
> > + return gsi;
> > +
> > + hwirq = gsi - acpi_pchpic[id]->gsi_base;
> > + fwspec.param_count = 2;
> > + fwspec.param[0] = hwirq;
> > + fwspec.param[1] = IRQ_TYPE_LEVEL_HIGH;
> > +
> > + return irq_domain_alloc_irqs(domain, 1, NUMA_NO_NODE, &fwspec);
> > + }
> > +
> > + return -1;
> > +}
> > +EXPORT_SYMBOL_GPL(acpi_register_gsi);
> > +
> > +void acpi_unregister_gsi(u32 gsi)
> > +{
> > +
> > +}
> > +EXPORT_SYMBOL_GPL(acpi_unregister_gsi);
> > +
> > +void __iomem *__init __acpi_map_table(unsigned long phys, unsigned long size)
> > +{
> > +
> > + if (!phys || !size)
> > + return NULL;
> > +
> > + return early_memremap(phys, size);
> > +}
> > +void __init __acpi_unmap_table(void __iomem *map, unsigned long size)
> > +{
> > + if (!map || !size)
> > + return;
> > +
> > + early_memunmap(map, size);
> > +}
> > +
> > +void __init acpi_boot_table_init(void)
> > +{
> > + /*
> > + * If acpi_disabled, bail out
> > + */
> > + if (acpi_disabled)
> > + return;
> > +
> > + /*
> > + * Initialize the ACPI boot-time table parser.
> > + */
> > + if (acpi_table_init()) {
> > + disable_acpi();
> > + return;
> > + }
> > +}
> > +
> > +static int __init
> > +acpi_parse_cpuintc(union acpi_subtable_headers *header, const unsigned long end)
> > +{
> > + struct acpi_madt_core_pic *processor = NULL;
> > +
> > + processor = (struct acpi_madt_core_pic *)header;
> > + if (BAD_MADT_ENTRY(processor, end))
> > + return -EINVAL;
> > +
> > + acpi_table_print_madt_entry(&header->common);
> > +
> > + return 0;
> > +}
> > +
> > +static int __init
> > +acpi_parse_liointc(union acpi_subtable_headers *header, const unsigned long end)
> > +{
> > + struct acpi_madt_lio_pic *liointc = NULL;
> > +
> > + liointc = (struct acpi_madt_lio_pic *)header;
> > +
> > + if (BAD_MADT_ENTRY(liointc, end))
> > + return -EINVAL;
> > +
> > + acpi_liointc = liointc;
> > +
> > + return 0;
> > +}
> > +
> > +static int __init
> > +acpi_parse_eiointc(union acpi_subtable_headers *header, const unsigned long end)
> > +{
> > + static int id = 0;
> > + struct acpi_madt_eio_pic *eiointc = NULL;
> > +
> > + eiointc = (struct acpi_madt_eio_pic *)header;
> > +
> > + if (BAD_MADT_ENTRY(eiointc, end))
> > + return -EINVAL;
> > +
> > + acpi_eiointc[id++] = eiointc;
> > + loongson_sysconf.nr_io_pics = id;
> > +
> > + return 0;
> > +}
> > +
> > +static int __init
> > +acpi_parse_htintc(union acpi_subtable_headers *header, const unsigned long end)
> > +{
> > + struct acpi_madt_ht_pic *htintc = NULL;
> > +
> > + htintc = (struct acpi_madt_ht_pic *)header;
> > +
> > + if (BAD_MADT_ENTRY(htintc, end))
> > + return -EINVAL;
> > +
> > + acpi_htintc = htintc;
> > + loongson_sysconf.nr_io_pics = 1;
> > +
> > + return 0;
> > +}
> > +
> > +static int __init
> > +acpi_parse_pch_pic(union acpi_subtable_headers *header, const unsigned long end)
> > +{
> > + static int id = 0;
> > + struct acpi_madt_bio_pic *pchpic = NULL;
> > +
> > + pchpic = (struct acpi_madt_bio_pic *)header;
> > +
> > + if (BAD_MADT_ENTRY(pchpic, end))
> > + return -EINVAL;
> > +
> > + acpi_pchpic[id++] = pchpic;
> > +
> > + return 0;
> > +}
> > +
> > +static int __init
> > +acpi_parse_pch_msi(union acpi_subtable_headers *header, const unsigned long end)
> > +{
> > + static int id = 0;
> > + struct acpi_madt_msi_pic *pchmsi = NULL;
> > +
> > + pchmsi = (struct acpi_madt_msi_pic *)header;
> > +
> > + if (BAD_MADT_ENTRY(pchmsi, end))
> > + return -EINVAL;
> > +
> > + acpi_pchmsi[id++] = pchmsi;
> > +
> > + return 0;
> > +}
> > +
> > +static int __init
> > +acpi_parse_pch_lpc(union acpi_subtable_headers *header, const unsigned long end)
> > +{
> > + struct acpi_madt_lpc_pic *pchlpc = NULL;
> > +
> > + pchlpc = (struct acpi_madt_lpc_pic *)header;
> > +
> > + if (BAD_MADT_ENTRY(pchlpc, end))
> > + return -EINVAL;
> > +
> > + acpi_pchlpc = pchlpc;
> > +
> > + return 0;
> > +}
> > +
> > +static void __init acpi_process_madt(void)
> > +{
> > + int error;
> > +
> > + /* Parse MADT CPUINTC entries */
> > + error = acpi_table_parse_madt(ACPI_MADT_TYPE_CORE_PIC, acpi_parse_cpuintc, MAX_CORE_PIC);
> > + if (error < 0) {
> > + disable_acpi();
> > + pr_err(PREFIX "Invalid BIOS MADT (CPUINTC entries), ACPI disabled\n");
> > + return;
> > + }
> > +
> > + loongson_sysconf.nr_cpus = num_processors;
> > +
> > + /* Parse MADT LIOINTC entries */
> > + error = acpi_table_parse_madt(ACPI_MADT_TYPE_LIO_PIC, acpi_parse_liointc, 1);
> > + if (error < 0) {
> > + disable_acpi();
> > + pr_err(PREFIX "Invalid BIOS MADT (LIOINTC entries), ACPI disabled\n");
> > + return;
> > + }
> > +
> > + /* Parse MADT EIOINTC entries */
> > + error = acpi_table_parse_madt(ACPI_MADT_TYPE_EIO_PIC, acpi_parse_eiointc, MAX_IO_PICS);
> > + if (error < 0) {
> > + disable_acpi();
> > + pr_err(PREFIX "Invalid BIOS MADT (EIOINTC entries), ACPI disabled\n");
> > + return;
> > + }
> > +
> > + /* Parse MADT HTVEC entries */
> > + error = acpi_table_parse_madt(ACPI_MADT_TYPE_HT_PIC, acpi_parse_htintc, 1);
> > + if (error < 0) {
> > + disable_acpi();
> > + pr_err(PREFIX "Invalid BIOS MADT (HTVEC entries), ACPI disabled\n");
> > + return;
> > + }
> > +
> > + /* Parse MADT PCHPIC entries */
> > + error = acpi_table_parse_madt(ACPI_MADT_TYPE_BIO_PIC, acpi_parse_pch_pic, MAX_IO_PICS);
> > + if (error < 0) {
> > + disable_acpi();
> > + pr_err(PREFIX "Invalid BIOS MADT (PCHPIC entries), ACPI disabled\n");
> > + return;
> > + }
> > +
> > + /* Parse MADT PCHMSI entries */
> > + error = acpi_table_parse_madt(ACPI_MADT_TYPE_MSI_PIC, acpi_parse_pch_msi, MAX_IO_PICS);
> > + if (error < 0) {
> > + disable_acpi();
> > + pr_err(PREFIX "Invalid BIOS MADT (PCHMSI entries), ACPI disabled\n");
> > + return;
> > + }
> > +
> > + /* Parse MADT PCHLPC entries */
> > + error = acpi_table_parse_madt(ACPI_MADT_TYPE_LPC_PIC, acpi_parse_pch_lpc, 1);
> > + if (error < 0) {
> > + disable_acpi();
> > + pr_err(PREFIX "Invalid BIOS MADT (PCHLPC entries), ACPI disabled\n");
> > + return;
> > + }
> > +}
> > +
> > +int __init acpi_boot_init(void)
> > +{
> > + /*
> > + * If acpi_disabled, bail out
> > + */
> > + if (acpi_disabled)
> > + return -1;
> > +
> > + loongson_sysconf.boot_cpu_id = read_csr_cpuid();
> > +
> > + /*
> > + * Process the Multiple APIC Description Table (MADT), if present
> > + */
> > + acpi_process_madt();
> > +
> > + /* Do not enable ACPI SPCR console by default */
> > + acpi_parse_spcr(earlycon_acpi_spcr_enable, false);
> > +
> > + return 0;
> > +}
> > +
> > +void __init arch_reserve_mem_area(acpi_physical_address addr, size_t size)
> > +{
> > + memblock_mark_nomap(addr, size);
> > +}
> > diff --git a/arch/loongarch/kernel/cacheinfo.c b/arch/loongarch/kernel/cacheinfo.c
> > new file mode 100644
> > index 000000000000..bedeb3eb1157
> > --- /dev/null
> > +++ b/arch/loongarch/kernel/cacheinfo.c
> > @@ -0,0 +1,122 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * LoongArch cacheinfo support
> > + *
> > + * Copyright (C) 2020-2021 Loongson Technology Corporation Limited
> > + */
> > +#include <linux/cacheinfo.h>
> > +
> > +/* Populates leaf and increments to next leaf */
> > +#define populate_cache(cache, leaf, c_level, c_type) \
> > +do { \
> > + leaf->type = c_type; \
> > + leaf->level = c_level; \
> > + leaf->coherency_line_size = c->cache.linesz; \
> > + leaf->number_of_sets = c->cache.sets; \
> > + leaf->ways_of_associativity = c->cache.ways; \
> > + leaf->size = c->cache.linesz * c->cache.sets * \
> > + c->cache.ways; \
> > + leaf++; \
> > +} while (0)
> > +
> > +int init_cache_level(unsigned int cpu)
> > +{
> > + struct cpuinfo_loongarch *c = ¤t_cpu_data;
> > + struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
> > + int levels = 0, leaves = 0;
> > +
> > + /*
> > + * If Dcache is not set, we assume the cache structures
> > + * are not properly initialized.
> > + */
> > + if (c->dcache.waysize)
> > + levels += 1;
> > + else
> > + return -ENOENT;
> > +
> > +
> > + leaves += (c->icache.waysize) ? 2 : 1;
> > +
> > + if (c->vcache.waysize) {
> > + levels++;
> > + leaves++;
> > + }
> > +
> > + if (c->scache.waysize) {
> > + levels++;
> > + leaves++;
> > + }
> > +
> > + if (c->tcache.waysize) {
> > + levels++;
> > + leaves++;
> > + }
> > +
> > + this_cpu_ci->num_levels = levels;
> > + this_cpu_ci->num_leaves = leaves;
> > + return 0;
> > +}
> > +
> > +static inline bool cache_leaves_are_shared(struct cacheinfo *this_leaf,
> > + struct cacheinfo *sib_leaf)
> > +{
> > + return !((this_leaf->level == 1) || (this_leaf->level == 2));
> > +}
> > +
> > +static void cache_cpumap_setup(unsigned int cpu)
> > +{
> > + struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
> > + struct cacheinfo *this_leaf, *sib_leaf;
> > + unsigned int index;
> > +
> > + for (index = 0; index < this_cpu_ci->num_leaves; index++) {
> > + unsigned int i;
> > +
> > + this_leaf = this_cpu_ci->info_list + index;
> > + /* skip if shared_cpu_map is already populated */
> > + if (!cpumask_empty(&this_leaf->shared_cpu_map))
> > + continue;
> > +
> > + cpumask_set_cpu(cpu, &this_leaf->shared_cpu_map);
> > + for_each_online_cpu(i) {
> > + struct cpu_cacheinfo *sib_cpu_ci = get_cpu_cacheinfo(i);
> > +
> > + if (i == cpu || !sib_cpu_ci->info_list)
> > + continue;/* skip if itself or no cacheinfo */
> > + sib_leaf = sib_cpu_ci->info_list + index;
> > + if (cache_leaves_are_shared(this_leaf, sib_leaf)) {
> > + cpumask_set_cpu(cpu, &sib_leaf->shared_cpu_map);
> > + cpumask_set_cpu(i, &this_leaf->shared_cpu_map);
> > + }
> > + }
> > + }
> > +}
> > +
> > +int populate_cache_leaves(unsigned int cpu)
> > +{
> > + int level = 1;
> > + struct cpuinfo_loongarch *c = ¤t_cpu_data;
> > + struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
> > + struct cacheinfo *this_leaf = this_cpu_ci->info_list;
> > +
> > + if (c->icache.waysize) {
> > + populate_cache(dcache, this_leaf, level, CACHE_TYPE_DATA);
> > + populate_cache(icache, this_leaf, level++, CACHE_TYPE_INST);
> > + } else {
> > + populate_cache(dcache, this_leaf, level++, CACHE_TYPE_UNIFIED);
> > + }
> > +
> > + if (c->vcache.waysize)
> > + populate_cache(vcache, this_leaf, level++, CACHE_TYPE_UNIFIED);
> > +
> > + if (c->scache.waysize)
> > + populate_cache(scache, this_leaf, level++, CACHE_TYPE_UNIFIED);
> > +
> > + if (c->tcache.waysize)
> > + populate_cache(tcache, this_leaf, level++, CACHE_TYPE_UNIFIED);
> > +
> > + cache_cpumap_setup(cpu);
> > + this_cpu_ci->cpu_map_populated = true;
> > +
> > + return 0;
> > +}
> > diff --git a/arch/loongarch/kernel/cmdline.c b/arch/loongarch/kernel/cmdline.c
> > new file mode 100644
> > index 000000000000..46bf4486b54c
> > --- /dev/null
> > +++ b/arch/loongarch/kernel/cmdline.c
> > @@ -0,0 +1,28 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Copyright (C) 2020-2021 Loongson Technology Corporation Limited
> > + */
> > +#include <linux/init.h>
> > +#include <linux/kernel.h>
> > +#include <linux/string.h>
> > +
> > +#include <asm/fw.h>
> > +
> > +int fw_argc;
> > +long *_fw_argv, *_fw_envp;
> > +
> > +void __init fw_init_cmdline(void)
> > +{
> > + int i;
> > +
> > + fw_argc = fw_arg0;
> > + _fw_argv = (long *)fw_arg1;
> > + _fw_envp = (long *)fw_arg2;
> > +
> > + arcs_cmdline[0] = '\0';
> > + for (i = 1; i < fw_argc; i++) {
> > + strlcat(arcs_cmdline, fw_argv(i), COMMAND_LINE_SIZE);
> > + if (i < (fw_argc - 1))
> > + strlcat(arcs_cmdline, " ", COMMAND_LINE_SIZE);
> > + }
> > +}
> > diff --git a/arch/loongarch/kernel/cpu-probe.c b/arch/loongarch/kernel/cpu-probe.c
> > new file mode 100644
> > index 000000000000..acf7eb19f75d
> > --- /dev/null
> > +++ b/arch/loongarch/kernel/cpu-probe.c
> > @@ -0,0 +1,301 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Processor capabilities determination functions.
> > + *
> > + * Copyright (C) 2020-2021 Loongson Technology Corporation Limited
> > + */
> > +#include <linux/init.h>
> > +#include <linux/kernel.h>
> > +#include <linux/ptrace.h>
> > +#include <linux/smp.h>
> > +#include <linux/stddef.h>
> > +#include <linux/export.h>
> > +#include <linux/printk.h>
> > +#include <linux/uaccess.h>
> > +
> > +#include <asm/cpu-features.h>
> > +#include <asm/elf.h>
> > +#include <asm/fpu.h>
> > +#include <asm/loongarch.h>
> > +#include <asm/pgtable-bits.h>
> > +#include <asm/setup.h>
> > +
> > +/* Hardware capabilities */
> > +unsigned int elf_hwcap __read_mostly;
> > +EXPORT_SYMBOL_GPL(elf_hwcap);
> > +
> > +/*
> > + * Determine the FCSR mask for FPU hardware.
> > + */
> > +static inline void cpu_set_fpu_fcsr_mask(struct cpuinfo_loongarch *c)
> > +{
> > + unsigned long sr, mask, fcsr, fcsr0, fcsr1;
> > +
> > + fcsr = c->fpu_csr0;
> > + mask = FPU_CSR_ALL_X | FPU_CSR_ALL_E | FPU_CSR_ALL_S | FPU_CSR_RM;
> > +
> > + sr = read_csr_euen();
> > + enable_fpu();
> > +
> > + fcsr0 = fcsr & mask;
> > + write_fcsr(LOONGARCH_FCSR0, fcsr0);
> > + fcsr0 = read_fcsr(LOONGARCH_FCSR0);
> > +
> > + fcsr1 = fcsr | ~mask;
> > + write_fcsr(LOONGARCH_FCSR0, fcsr1);
> > + fcsr1 = read_fcsr(LOONGARCH_FCSR0);
> > +
> > + write_fcsr(LOONGARCH_FCSR0, fcsr);
> > +
> > + write_csr_euen(sr);
> > +
> > + c->fpu_mask = ~(fcsr0 ^ fcsr1) & ~mask;
> > +}
> > +
> > +static inline void set_elf_platform(int cpu, const char *plat)
> > +{
> > + if (cpu == 0)
> > + __elf_platform = plat;
> > +}
> > +
> > +/* MAP BASE */
> > +unsigned long vm_map_base;
> > +EXPORT_SYMBOL_GPL(vm_map_base);
> > +
> > +static void cpu_probe_addrbits(struct cpuinfo_loongarch *c)
> > +{
> > +#ifdef __NEED_ADDRBITS_PROBE
> > + c->pabits = (read_cpucfg(LOONGARCH_CPUCFG1) & CPUCFG1_PABITS) >> 4;
> > + c->vabits = (read_cpucfg(LOONGARCH_CPUCFG1) & CPUCFG1_VABITS) >> 12;
> > + vm_map_base = 0UL - (1UL << c->vabits);
> > +#endif
> > +}
> > +
> > +static void set_isa(struct cpuinfo_loongarch *c, unsigned int isa)
> > +{
> > + switch (isa) {
> > + case LOONGARCH_CPU_ISA_LA64:
> > + c->isa_level |= LOONGARCH_CPU_ISA_LA64;
> > + fallthrough;
> > + case LOONGARCH_CPU_ISA_LA32S:
> > + c->isa_level |= LOONGARCH_CPU_ISA_LA32S;
> > + fallthrough;
> > + case LOONGARCH_CPU_ISA_LA32R:
> > + c->isa_level |= LOONGARCH_CPU_ISA_LA32R;
> > + break;
> > + }
> > +}
> > +
> > +static void cpu_probe_common(struct cpuinfo_loongarch *c)
> > +{
> > + unsigned int config;
> > + unsigned long asid_mask;
> > +
> > + c->options = LOONGARCH_CPU_CPUCFG | LOONGARCH_CPU_CSR |
> > + LOONGARCH_CPU_TLB | LOONGARCH_CPU_VINT | LOONGARCH_CPU_WATCH;
> > +
> > + elf_hwcap |= HWCAP_LOONGARCH_CRC32;
> > +
> > + config = read_cpucfg(LOONGARCH_CPUCFG1);
> > + if (config & CPUCFG1_UAL) {
> > + c->options |= LOONGARCH_CPU_UAL;
> > + elf_hwcap |= HWCAP_LOONGARCH_UAL;
> > + }
> > +
> > + config = read_cpucfg(LOONGARCH_CPUCFG2);
> > + if (config & CPUCFG2_LAM) {
> > + c->options |= LOONGARCH_CPU_LAM;
> > + elf_hwcap |= HWCAP_LOONGARCH_LAM;
> > + }
> > + if (config & CPUCFG2_FP) {
> > + c->options |= LOONGARCH_CPU_FPU;
> > + elf_hwcap |= HWCAP_LOONGARCH_FPU;
> > + }
> > + if (config & CPUCFG2_COMPLEX) {
> > + c->options |= LOONGARCH_CPU_COMPLEX;
> > + elf_hwcap |= HWCAP_LOONGARCH_COMPLEX;
> > + }
> > + if (config & CPUCFG2_CRYPTO) {
> > + c->options |= LOONGARCH_CPU_CRYPTO;
> > + elf_hwcap |= HWCAP_LOONGARCH_CRYPTO;
> > + }
> > + if (config & CPUCFG2_LVZP) {
> > + c->options |= LOONGARCH_CPU_LVZ;
> > + elf_hwcap |= HWCAP_LOONGARCH_LVZ;
> > + }
> > +
> > + config = read_cpucfg(LOONGARCH_CPUCFG6);
> > + if (config & CPUCFG6_PMP)
> > + c->options |= LOONGARCH_CPU_PMP;
> > +
> > + config = iocsr_readl(LOONGARCH_IOCSR_FEATURES);
> > + if (config & IOCSRF_CSRIPI)
> > + c->options |= LOONGARCH_CPU_CSRIPI;
> > + if (config & IOCSRF_EXTIOI)
> > + c->options |= LOONGARCH_CPU_EXTIOI;
> > + if (config & IOCSRF_FREQSCALE)
> > + c->options |= LOONGARCH_CPU_SCALEFREQ;
> > + if (config & IOCSRF_VM)
> > + c->options |= LOONGARCH_CPU_HYPERVISOR;
> > +
> > + config = csr_readl(LOONGARCH_CSR_ASID);
> > + config = (config & CSR_ASID_BIT) >> CSR_ASID_BIT_SHIFT;
> > + asid_mask = GENMASK(config - 1, 0);
> > + set_cpu_asid_mask(c, asid_mask);
> > +
> > + config = read_csr_prcfg1();
> > + c->kscratch_mask = GENMASK((config & CSR_CONF1_KSNUM) - 1, 0);
> > + c->kscratch_mask &= ~(EXC_KSCRATCH_MASK | PERCPU_KSCRATCH_MASK | KVM_KSCRATCH_MASK);
> > +
> > + config = read_csr_prcfg3();
> > + switch (config & CSR_CONF3_TLBTYPE) {
> > + case 0:
> > + c->tlbsizemtlb = 0;
> > + c->tlbsizestlbsets = 0;
> > + c->tlbsizestlbways = 0;
> > + c->tlbsize = 0;
> > + break;
> > + case 1:
> > + c->tlbsizemtlb = ((config & CSR_CONF3_MTLBSIZE) >> CSR_CONF3_MTLBSIZE_SHIFT) + 1;
> > + c->tlbsizestlbsets = 0;
> > + c->tlbsizestlbways = 0;
> > + c->tlbsize = c->tlbsizemtlb + c->tlbsizestlbsets * c->tlbsizestlbways;
> > + break;
> > + case 2:
> > + c->tlbsizemtlb = ((config & CSR_CONF3_MTLBSIZE) >> CSR_CONF3_MTLBSIZE_SHIFT) + 1;
> > + c->tlbsizestlbsets = 1 << ((config & CSR_CONF3_STLBIDX) >> CSR_CONF3_STLBIDX_SHIFT);
> > + c->tlbsizestlbways = ((config & CSR_CONF3_STLBWAYS) >> CSR_CONF3_STLBWAYS_SHIFT) + 1;
> > + c->tlbsize = c->tlbsizemtlb + c->tlbsizestlbsets * c->tlbsizestlbways;
> > + break;
> > + default:
> > + pr_warn("Warning: unimplemented tlb type\n");
> > + }
> > +}
> > +
> > +#define MAX_NAME_LEN 32
> > +#define VENDOR_OFFSET 0
> > +#define CPUNAME_OFFSET 9
> > +
> > +static char cpu_full_name[MAX_NAME_LEN] = " - ";
> > +
> > +static inline void cpu_probe_loongson(struct cpuinfo_loongarch *c, unsigned int cpu)
> > +{
> > + uint64_t *vendor = (void *)(&cpu_full_name[VENDOR_OFFSET]);
> > + uint64_t *cpuname = (void *)(&cpu_full_name[CPUNAME_OFFSET]);
> > +
> > + __cpu_full_name[cpu] = cpu_full_name;
> > + *vendor = iocsr_readq(LOONGARCH_IOCSR_VENDOR);
> > + *cpuname = iocsr_readq(LOONGARCH_IOCSR_CPUNAME);
> > +
> > + switch (c->processor_id & PRID_IMP_MASK) {
> > + case PRID_IMP_LOONGSON_32:
> > + c->cputype = CPU_LOONGSON32;
> > + set_isa(c, LOONGARCH_CPU_ISA_LA32S);
> > + __cpu_family[cpu] = "Loongson-32bit";
> > + pr_info("Standard 32-bit Loongson Processor probed\n");
> > + break;
> > + case PRID_IMP_LOONGSON_64R:
> > + c->cputype = CPU_LOONGSON64;
> > + set_isa(c, LOONGARCH_CPU_ISA_LA64);
> > + __cpu_family[cpu] = "Loongson-64bit";
> > + pr_info("Reduced 64-bit Loongson Processor probed\n");
> > + break;
> > + case PRID_IMP_LOONGSON_64C:
> > + c->cputype = CPU_LOONGSON64;
> > + set_isa(c, LOONGARCH_CPU_ISA_LA64);
> > + __cpu_family[cpu] = "Loongson-64bit";
> > + pr_info("Classic 64-bit Loongson Processor probed\n");
> > + break;
> > + case PRID_IMP_LOONGSON_64G:
> > + c->cputype = CPU_LOONGSON64;
> > + set_isa(c, LOONGARCH_CPU_ISA_LA64);
> > + __cpu_family[cpu] = "Loongson-64bit";
> > + pr_info("Generic 64-bit Loongson Processor probed\n");
> > + break;
> > + default: /* Default to 64 bit */
> > + c->cputype = CPU_LOONGSON64;
> > + set_isa(c, LOONGARCH_CPU_ISA_LA64);
> > + __cpu_family[cpu] = "Loongson-64bit";
> > + pr_info("Unknown 64-bit Loongson Processor probed\n");
> > + }
> > +}
> > +
> > +#ifdef CONFIG_64BIT
> > +/* For use by uaccess.h */
> > +u64 __ua_limit;
> > +EXPORT_SYMBOL(__ua_limit);
> > +#endif
> > +
> > +const char *__cpu_family[NR_CPUS];
> > +const char *__cpu_full_name[NR_CPUS];
> > +const char *__elf_platform;
> > +
> > +static void cpu_report(void)
> > +{
> > + struct cpuinfo_loongarch *c = ¤t_cpu_data;
> > +
> > + pr_info("CPU%d revision is: %08x (%s)\n",
> > + smp_processor_id(), c->processor_id, cpu_family_string());
> > + if (c->options & LOONGARCH_CPU_FPU)
> > + pr_info("FPU%d revision is: %08x\n", smp_processor_id(), c->fpu_vers);
> > +}
> > +
> > +void cpu_probe(void)
> > +{
> > + unsigned int cpu = smp_processor_id();
> > + struct cpuinfo_loongarch *c = ¤t_cpu_data;
> > +
> > + /*
> > + * Set a default elf platform, cpu probe may later
> > + * overwrite it with a more precise value
> > + */
> > + set_elf_platform(cpu, "loongarch");
> > +
> > + c->cputype = CPU_UNKNOWN;
> > + c->processor_id = read_cpucfg(LOONGARCH_CPUCFG0);
> > + c->fpu_vers = (read_cpucfg(LOONGARCH_CPUCFG2) >> 3) & 0x3;
> > +
> > + c->fpu_csr0 = FPU_CSR_RN;
> > + c->fpu_mask = FPU_CSR_RSVD;
> > +
> > + cpu_probe_common(c);
> > +
> > + per_cpu_trap_init(cpu);
> > +
> > + switch (c->processor_id & PRID_COMP_MASK) {
> > + case PRID_COMP_LOONGSON:
> > + cpu_probe_loongson(c, cpu);
> > + break;
> > + }
> > +
> > + BUG_ON(!__cpu_family[cpu]);
> > + BUG_ON(c->cputype == CPU_UNKNOWN);
> > +
> > + cpu_probe_addrbits(c);
> > +
> > +#ifdef CONFIG_64BIT
> > + if (cpu == 0)
> > + __ua_limit = ~((1ull << cpu_vabits) - 1);
> > +#endif
> > +
> > + cpu_report();
> > +}
> > +
> > +void cpu_set_cluster(struct cpuinfo_loongarch *cpuinfo, unsigned int cluster)
> > +{
> > + /* Ensure the core number fits in the field */
> > + WARN_ON(cluster > (LOONGARCH_GLOBALNUMBER_CLUSTER >>
> > + LOONGARCH_GLOBALNUMBER_CLUSTER_SHF));
> > +
> > + cpuinfo->globalnumber &= ~LOONGARCH_GLOBALNUMBER_CLUSTER;
> > + cpuinfo->globalnumber |= cluster << LOONGARCH_GLOBALNUMBER_CLUSTER_SHF;
> > +}
> > +
> > +void cpu_set_core(struct cpuinfo_loongarch *cpuinfo, unsigned int core)
> > +{
> > + /* Ensure the core number fits in the field */
> > + WARN_ON(core > (LOONGARCH_GLOBALNUMBER_CORE >> LOONGARCH_GLOBALNUMBER_CORE_SHF));
> > +
> > + cpuinfo->globalnumber &= ~LOONGARCH_GLOBALNUMBER_CORE;
> > + cpuinfo->globalnumber |= core << LOONGARCH_GLOBALNUMBER_CORE_SHF;
> > +}
> > diff --git a/arch/loongarch/kernel/efi.c b/arch/loongarch/kernel/efi.c
> > new file mode 100644
> > index 000000000000..c05abd143e44
> > --- /dev/null
> > +++ b/arch/loongarch/kernel/efi.c
> > @@ -0,0 +1,95 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * EFI initialization
> > + *
> > + * Author: Jianmin Lv <lvjianmin@...ngson.cn>
> > + * Huacai Chen <chenhuacai@...ngson.cn>
> > + *
> > + * Copyright (C) 2020-2021 Loongson Technology Corporation Limited
> > + */
> > +
> > +#include <linux/acpi.h>
> > +#include <linux/efi.h>
> > +#include <linux/efi-bgrt.h>
> > +#include <linux/init.h>
> > +#include <linux/kernel.h>
> > +#include <linux/export.h>
> > +#include <linux/io.h>
> > +#include <linux/kobject.h>
> > +#include <linux/memblock.h>
> > +#include <linux/reboot.h>
> > +#include <linux/uaccess.h>
> > +
> > +#include <asm/efi.h>
> > +#include <asm/boot_param.h>
> > +
> > +static efi_config_table_type_t arch_tables[] __initdata = {{},};
> > +
> > +void __init efi_runtime_init(void)
> > +{
> > + if (!efi_enabled(EFI_BOOT))
> > + return;
> > +
> > + if (!efi.runtime)
> > + return;
> > +
> > + if (efi_runtime_disabled()) {
> > + pr_info("EFI runtime services will be disabled.\n");
> > + return;
> > + }
> > +
> > + efi_native_runtime_setup();
> > + set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
> > +}
> > +
> > +void __init efi_init(void)
> > +{
> > + unsigned long efi_config_table;
> > + efi_system_table_t *efi_systab;
> > +
> > + if (!efi_bp)
> > + return;
> > +
> > + efi_systab = (efi_system_table_t *)efi_bp->systemtable;
> > + if (!efi_systab) {
> > + pr_err("Can't find EFI system table.\n");
> > + return;
> > + }
> > +
> > + set_bit(EFI_64BIT, &efi.flags);
> > + efi_config_table = (unsigned long)efi_systab->tables;
> > + efi.runtime = (efi_runtime_services_t *)efi_systab->runtime;
> > + efi.runtime_version = efi.runtime ? (unsigned int)efi.runtime->hdr.revision : 0;
> > +
> > + efi_config_parse_tables((void *)efi_systab->tables, efi_systab->nr_tables, arch_tables);
> > +}
> > +
> > +static ssize_t boardinfo_show(struct kobject *kobj,
> > + struct kobj_attribute *attr, char *buf)
> > +{
> > + return sprintf(buf,
> > + "BIOS Information\n"
> > + "Vendor\t\t\t: %s\n"
> > + "Version\t\t\t: %s\n"
> > + "ROM Size\t\t: %d KB\n"
> > + "Release Date\t\t: %s\n\n"
> > + "Board Information\n"
> > + "Manufacturer\t\t: %s\n"
> > + "Board Name\t\t: %s\n"
> > + "Family\t\t\t: LOONGSON64\n\n",
> > + b_info.bios_vendor, b_info.bios_version,
> > + b_info.bios_size, b_info.bios_release_date,
> > + b_info.board_vendor, b_info.board_name);
> > +}
> > +
> > +static struct kobj_attribute boardinfo_attr = __ATTR(boardinfo, 0444,
> > + boardinfo_show, NULL);
> > +
> > +static int __init boardinfo_init(void)
> > +{
> > + if (!efi_kobj)
> > + return -EINVAL;
> > +
> > + return sysfs_create_file(efi_kobj, &boardinfo_attr.attr);
> > +}
> > +late_initcall(boardinfo_init);
> > diff --git a/arch/loongarch/kernel/env.c b/arch/loongarch/kernel/env.c
> > new file mode 100644
> > index 000000000000..234fe282a98c
> > --- /dev/null
> > +++ b/arch/loongarch/kernel/env.c
> > @@ -0,0 +1,170 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Author: Huacai Chen <chenhuacai@...ngson.cn>
> > + *
> > + * Copyright (C) 2020-2021 Loongson Technology Corporation Limited
> > + */
> > +#include <linux/export.h>
> > +#include <linux/acpi.h>
> > +#include <linux/efi.h>
> > +#include <asm/fw.h>
> > +#include <asm/time.h>
> > +#include <asm/bootinfo.h>
> > +#include <asm/loongson.h>
> > +
> > +struct bootparamsinterface *efi_bp;
> > +struct loongsonlist_mem_map *loongson_mem_map;
> > +struct loongsonlist_vbios *pvbios;
> > +struct loongson_system_configuration loongson_sysconf;
> > +EXPORT_SYMBOL(loongson_sysconf);
> > +
> > +u64 loongson_chipcfg[MAX_PACKAGES];
> > +u64 loongson_chiptemp[MAX_PACKAGES];
> > +u64 loongson_freqctrl[MAX_PACKAGES];
> > +unsigned long long smp_group[MAX_PACKAGES];
> > +
> > +static void __init register_addrs_set(u64 *registers, const u64 addr, int num)
> > +{
> > + u64 i;
> > +
> > + for (i = 0; i < num; i++) {
> > + *registers = (i << 44) | addr;
> > + registers++;
> > + }
> > +}
> > +
> > +static u8 ext_listhdr_checksum(u8 *buffer, u32 length)
> > +{
> > + u8 sum = 0;
> > + u8 *end = buffer + length;
> > +
> > + while (buffer < end) {
> > + sum = (u8)(sum + *(buffer++));
> > + }
> > +
> > + return (sum);
> > +}
> > +
> > +static int parse_mem(struct _extention_list_hdr *head)
> > +{
> > + loongson_mem_map = (struct loongsonlist_mem_map *)head;
> > + if (ext_listhdr_checksum((u8 *)loongson_mem_map, head->length)) {
> > + pr_warn("mem checksum error\n");
> > + return -EPERM;
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static int parse_vbios(struct _extention_list_hdr *head)
> > +{
> > + pvbios = (struct loongsonlist_vbios *)head;
> > +
> > + if (ext_listhdr_checksum((u8 *)pvbios, head->length)) {
> > + pr_warn("vbios_addr checksum error\n");
> > + return -EPERM;
> > + }
> > +
> > + loongson_sysconf.vgabios_addr = pvbios->vbios_addr;
> > +
> > + return 0;
> > +}
> > +
> > +static int parse_screeninfo(struct _extention_list_hdr *head)
> > +{
> > + struct loongsonlist_screeninfo *pscreeninfo;
> > +
> > + pscreeninfo = (struct loongsonlist_screeninfo *)head;
> > + if (ext_listhdr_checksum((u8 *)pscreeninfo, head->length)) {
> > + pr_warn("screeninfo_addr checksum error\n");
> > + return -EPERM;
> > + }
> > +
> > + memcpy(&screen_info, &pscreeninfo->si, sizeof(screen_info));
> > +
> > + return 0;
> > +}
> > +
> > +static int list_find(struct _extention_list_hdr *head)
> > +{
> > + struct _extention_list_hdr *fhead = head;
> > +
> > + if (fhead == NULL) {
> > + pr_warn("the link is empty!\n");
> > + return -1;
> > + }
> > +
> > + while (fhead != NULL) {
> > + if (memcmp(&(fhead->signature), LOONGSON_MEM_LINKLIST, 3) == 0) {
> > + if (parse_mem(fhead) != 0) {
> > + pr_warn("parse mem failed\n");
> > + return -EPERM;
> > + }
> > + } else if (memcmp(&(fhead->signature), LOONGSON_VBIOS_LINKLIST, 5) == 0) {
> > + if (parse_vbios(fhead) != 0) {
> > + pr_warn("parse vbios failed\n");
> > + return -EPERM;
> > + }
> > + } else if (memcmp(&(fhead->signature), LOONGSON_SCREENINFO_LINKLIST, 5) == 0) {
> > + if (parse_screeninfo(fhead) != 0) {
> > + pr_warn("parse screeninfo failed\n");
> > + return -EPERM;
> > + }
> > + }
> > + fhead = fhead->next;
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static void __init parse_bpi_flags(void)
> > +{
> > + if (efi_bp->flags & BPI_FLAGS_UEFI_SUPPORTED)
> > + set_bit(EFI_BOOT, &efi.flags);
> > + else
> > + clear_bit(EFI_BOOT, &efi.flags);
> > +}
> > +
> > +static int get_bpi_version(void *signature)
> > +{
> > + char data[8];
> > + int r, version = 0;
> > +
> > + memset(data, 0, 8);
> > + memcpy(data, signature + 4, 4);
> > + r = kstrtoint(data, 10, &version);
> > +
> > + if (r < 0 || version < BPI_VERSION_V1)
> > + panic("Fatal error, invalid BPI version: %d\n", version);
> > +
> > + if (version >= BPI_VERSION_V2)
> > + parse_bpi_flags();
> > +
> > + return version;
> > +}
> > +
> > +void __init fw_init_environ(void)
> > +{
> > + efi_bp = (struct bootparamsinterface *)_fw_envp;
> > + loongson_sysconf.bpi_ver = get_bpi_version(&efi_bp->signature);
> > +
> > + register_addrs_set(smp_group, TO_UNCAC(0x1fe01000), 16);
> > + register_addrs_set(loongson_chipcfg, TO_UNCAC(0x1fe00180), 16);
> > + register_addrs_set(loongson_chiptemp, TO_UNCAC(0x1fe0019c), 16);
> > + register_addrs_set(loongson_freqctrl, TO_UNCAC(0x1fe001d0), 16);
> > +
> > + if (list_find(efi_bp->extlist))
> > + pr_warn("Scan bootparam failed\n");
> > +}
> > +
> > +static int __init init_cpu_fullname(void)
> > +{
> > + int cpu;
> > +
> > + if (loongson_sysconf.cpuname && !strncmp(loongson_sysconf.cpuname, "Loongson", 8)) {
> > + for (cpu = 0; cpu < NR_CPUS; cpu++)
> > + __cpu_full_name[cpu] = loongson_sysconf.cpuname;
> > + }
> > + return 0;
> > +}
> > +arch_initcall(init_cpu_fullname);
> > diff --git a/arch/loongarch/kernel/head.S b/arch/loongarch/kernel/head.S
> > new file mode 100644
> > index 000000000000..53e02fb0559d
> > --- /dev/null
> > +++ b/arch/loongarch/kernel/head.S
> > @@ -0,0 +1,72 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/*
> > + * Copyright (C) 2020-2021 Loongson Technology Corporation Limited
> > + */
> > +#include <linux/init.h>
> > +#include <linux/threads.h>
> > +
> > +#include <asm/addrspace.h>
> > +#include <asm/asm.h>
> > +#include <asm/asmmacro.h>
> > +#include <asm/regdef.h>
> > +#include <asm/loongarch.h>
> > +#include <asm/stackframe.h>
> > +
> > +SYM_ENTRY(_stext, SYM_L_GLOBAL, SYM_A_NONE)
> > +
> > + __REF
> > +
> > +SYM_CODE_START(kernel_entry) # kernel entry point
> > +
> > + /* We might not get launched at the address the kernel is linked to,
> > + so we jump there. */
> > + la.abs t0, 0f
> > + jirl zero, t0, 0
> > +0:
> > + la t0, __bss_start # clear .bss
> > + st.d zero, t0, 0
> > + la t1, __bss_stop - LONGSIZE
> > +1:
> > + addi.d t0, t0, LONGSIZE
> > + st.d zero, t0, 0
> > + bne t0, t1, 1b
> > +
> > + la t0, fw_arg0
> > + st.d a0, t0, 0 # firmware arguments
> > + la t0, fw_arg1
> > + st.d a1, t0, 0
> > + la t0, fw_arg2
> > + st.d a2, t0, 0
> > + la t0, fw_arg3
> > + st.d a3, t0, 0
> > +
> > + /* Config direct window and set PG */
> > + li.d t0, CSR_DMW0_INIT # UC, PLV0, 0x8000 xxxx xxxx xxxx
> > + csrwr t0, LOONGARCH_CSR_DMWIN0
> > + li.d t0, CSR_DMW1_INIT # CA, PLV0, 0x9000 xxxx xxxx xxxx
> > + csrwr t0, LOONGARCH_CSR_DMWIN1
> > + /* Enable PG */
> > + li.w t0, 0xb0 # PLV=0, IE=0, PG=1
> > + csrwr t0, LOONGARCH_CSR_CRMD
> > + li.w t0, 0x04 # PLV=0, PIE=1, PWE=0
> > + csrwr t0, LOONGARCH_CSR_PRMD
> > + li.w t0, 0x00 # FPE=0, SXE=0, ASXE=0, BTE=0
> > + csrwr t0, LOONGARCH_CSR_EUEN
> > +
> > + /* KScratch3 used for percpu base, initialized as 0 */
> > + csrwr zero, PERCPU_BASE_KS
> > + /* GPR21 used for percpu base (runtime), initialized as 0 */
> > + or x0, zero, zero
> > +
> > + la tp, init_thread_union
> > + /* Set the SP after an empty pt_regs. */
> > + PTR_LI sp, (_THREAD_SIZE - 32 - PT_SIZE)
> > + PTR_ADDU sp, sp, tp
> > + set_saved_sp sp, t0, t1
> > + PTR_ADDIU sp, sp, -4 * SZREG # init stack pointer
> > +
> > + bl start_kernel
> > +
> > +SYM_CODE_END(kernel_entry)
> > +
> > +SYM_ENTRY(kernel_entry_end, SYM_L_GLOBAL, SYM_A_NONE)
> > diff --git a/arch/loongarch/kernel/mem.c b/arch/loongarch/kernel/mem.c
> > new file mode 100644
> > index 000000000000..c1ac71034448
> > --- /dev/null
> > +++ b/arch/loongarch/kernel/mem.c
> > @@ -0,0 +1,83 @@
> > +// SPDX-License-Identifier: GPL-2.0-or-later
> > +/*
> > + * Copyright (C) 2020-2021 Loongson Technology Corporation Limited
> > + */
> > +#include <linux/fs.h>
> > +#include <linux/mm.h>
> > +#include <linux/memblock.h>
> > +
> > +#include <asm/bootinfo.h>
> > +#include <asm/loongson.h>
> > +#include <asm/sections.h>
> > +
> > +void __init early_memblock_init(void)
> > +{
> > + int i;
> > + u32 mem_type;
> > + u64 mem_start, mem_end, mem_size;
> > +
> > + /* parse memory information */
> > + for (i = 0; i < loongson_mem_map->map_count; i++) {
> > + mem_type = loongson_mem_map->map[i].mem_type;
> > + mem_start = loongson_mem_map->map[i].mem_start;
> > + mem_size = loongson_mem_map->map[i].mem_size;
> > + mem_end = mem_start + mem_size;
> > +
> > + switch (mem_type) {
> > + case ADDRESS_TYPE_SYSRAM:
> > + memblock_add(mem_start, mem_size);
> > + if (max_low_pfn < (mem_end >> PAGE_SHIFT))
> > + max_low_pfn = mem_end >> PAGE_SHIFT;
> > + break;
> > + }
> > + }
> > + memblock_set_current_limit(PFN_PHYS(max_low_pfn));
> > +}
> > +
> > +void __init fw_init_memory(void)
> > +{
> > + int i;
> > + u32 mem_type;
> > + u64 mem_start, mem_end, mem_size;
> > + unsigned long start_pfn, end_pfn;
> > + static unsigned long num_physpages;
> > +
> > + /* parse memory information */
> > + for (i = 0; i < loongson_mem_map->map_count; i++) {
> > + mem_type = loongson_mem_map->map[i].mem_type;
> > + mem_start = loongson_mem_map->map[i].mem_start;
> > + mem_size = loongson_mem_map->map[i].mem_size;
> > + mem_end = mem_start + mem_size;
> > +
> > + switch (mem_type) {
> > + case ADDRESS_TYPE_SYSRAM:
> > + mem_start = PFN_ALIGN(mem_start);
> > + mem_end = PFN_ALIGN(mem_end - PAGE_SIZE + 1);
> > + num_physpages += (mem_size >> PAGE_SHIFT);
> > + memblock_set_node(mem_start, mem_size, &memblock.memory, 0);
> > + break;
> > + case ADDRESS_TYPE_ACPI:
> > + case ADDRESS_TYPE_RESERVED:
> > + memblock_reserve(loongson_mem_map->map[i].mem_start,
> > + loongson_mem_map->map[i].mem_size);
> > + break;
> > + }
> > + }
> > +
> > + get_pfn_range_for_nid(0, &start_pfn, &end_pfn);
> > + pr_info("start_pfn=0x%lx, end_pfn=0x%lx, num_physpages:0x%lx\n",
> > + start_pfn, end_pfn, num_physpages);
> > +
> > + NODE_DATA(0)->node_start_pfn = start_pfn;
> > + NODE_DATA(0)->node_spanned_pages = end_pfn - start_pfn;
> > +
> > + /* used by finalize_initrd() */
> > + max_low_pfn = end_pfn;
> > +
> > + /* Reserve the first 2MB */
> > + memblock_reserve(PHYS_OFFSET, 0x200000);
> > +
> > + /* Reserve the kernel text/data/bss */
> > + memblock_reserve(__pa_symbol(&_text),
> > + __pa_symbol(&_end) - __pa_symbol(&_text));
> > +}
> > diff --git a/arch/loongarch/kernel/reset.c b/arch/loongarch/kernel/reset.c
> > new file mode 100644
> > index 000000000000..b140c2aa2c5a
> > --- /dev/null
> > +++ b/arch/loongarch/kernel/reset.c
> > @@ -0,0 +1,90 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Copyright (C) 2020-2021 Loongson Technology Corporation Limited
> > + */
> > +#include <linux/kernel.h>
> > +#include <linux/acpi.h>
> > +#include <linux/efi.h>
> > +#include <linux/export.h>
> > +#include <linux/pm.h>
> > +#include <linux/types.h>
> > +#include <linux/reboot.h>
> > +#include <linux/delay.h>
> > +#include <linux/console.h>
> > +
> > +#include <acpi/reboot.h>
> > +#include <asm/compiler.h>
> > +#include <asm/idle.h>
> > +#include <asm/loongarch.h>
> > +#include <asm/reboot.h>
> > +
> > +static void default_halt(void)
> > +{
> > + local_irq_disable();
> > + clear_csr_ecfg(ECFG0_IM);
> > +
> > + pr_notice("\n\n** You can safely turn off the power now **\n\n");
> > + console_flush_on_panic(CONSOLE_FLUSH_PENDING);
> > +
> > + while (true) {
> > + __arch_cpu_idle();
> > + }
> > +}
> > +
> > +static void default_poweroff(void)
> > +{
> > +#ifdef CONFIG_EFI
> > + efi.reset_system(EFI_RESET_SHUTDOWN, EFI_SUCCESS, 0, NULL);
> > +#endif
> > + while (true) {
> > + __arch_cpu_idle();
> > + }
> > +}
> > +
> > +static void default_restart(void)
> > +{
> > +#ifdef CONFIG_EFI
> > + if (efi_capsule_pending(NULL))
> > + efi_reboot(REBOOT_WARM, NULL);
> > + else
> > + efi_reboot(REBOOT_COLD, NULL);
> > +#endif
> > + if (!acpi_disabled)
> > + acpi_reboot();
> > +
> > + while (true) {
> > + __arch_cpu_idle();
> > + }
> > +}
> > +
> > +void (*pm_restart)(void);
> > +EXPORT_SYMBOL(pm_restart);
> > +
> > +void (*pm_power_off)(void);
> > +EXPORT_SYMBOL(pm_power_off);
> > +
> > +void machine_halt(void)
> > +{
> > + default_halt();
> > +}
> > +
> > +void machine_power_off(void)
> > +{
> > + pm_power_off();
> > +}
> > +
> > +void machine_restart(char *command)
> > +{
> > + do_kernel_restart(command);
> > + pm_restart();
> > +}
> > +
> > +static int __init loongarch_reboot_setup(void)
> > +{
> > + pm_restart = default_restart;
> > + pm_power_off = default_poweroff;
> > +
> > + return 0;
> > +}
> > +
> > +arch_initcall(loongarch_reboot_setup);
> > diff --git a/arch/loongarch/kernel/setup.c b/arch/loongarch/kernel/setup.c
> > new file mode 100644
> > index 000000000000..7ec32959b36c
> > --- /dev/null
> > +++ b/arch/loongarch/kernel/setup.c
> > @@ -0,0 +1,469 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Copyright (C) 2020-2021 Loongson Technology Corporation Limited
> > + *
> > + * Derived from MIPS:
> > + * Copyright (C) 1995 Linus Torvalds
> > + * Copyright (C) 1995 Waldorf Electronics
> > + * Copyright (C) 1994, 95, 96, 97, 98, 99, 2000, 01, 02, 03 Ralf Baechle
> > + * Copyright (C) 1996 Stoned Elipot
> > + * Copyright (C) 1999 Silicon Graphics, Inc.
> > + * Copyright (C) 2000, 2001, 2002, 2007 Maciej W. Rozycki
> > + */
> > +#include <linux/init.h>
> > +#include <linux/acpi.h>
> > +#include <linux/dmi.h>
> > +#include <linux/efi.h>
> > +#include <linux/export.h>
> > +#include <linux/screen_info.h>
> > +#include <linux/memblock.h>
> > +#include <linux/initrd.h>
> > +#include <linux/ioport.h>
> > +#include <linux/root_dev.h>
> > +#include <linux/console.h>
> > +#include <linux/pfn.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/sizes.h>
> > +#include <linux/device.h>
> > +#include <linux/dma-map-ops.h>
> > +#include <linux/swiotlb.h>
> > +
> > +#include <asm/addrspace.h>
> > +#include <asm/bootinfo.h>
> > +#include <asm/cache.h>
> > +#include <asm/cpu.h>
> > +#include <asm/dma.h>
> > +#include <asm/efi.h>
> > +#include <asm/fw.h>
> > +#include <asm/loongson.h>
> > +#include <asm/pgalloc.h>
> > +#include <asm/sections.h>
> > +#include <asm/setup.h>
> > +#include <asm/time.h>
> > +
> > +#define SMBIOS_BIOSSIZE_OFFSET 0x09
> > +#define SMBIOS_BIOSEXTERN_OFFSET 0x13
> > +#define SMBIOS_FREQLOW_OFFSET 0x16
> > +#define SMBIOS_FREQHIGH_OFFSET 0x17
> > +#define SMBIOS_FREQLOW_MASK 0xFF
> > +#define SMBIOS_CORE_PACKAGE_OFFSET 0x23
> > +#define LOONGSON_EFI_ENABLE (1 << 3)
> > +
> > +#ifdef CONFIG_VT
> > +struct screen_info screen_info;
> > +#endif
> > +
> > +DEFINE_PER_CPU(unsigned long, kernelsp);
> > +unsigned long fw_arg0, fw_arg1, fw_arg2, fw_arg3;
> > +struct cpuinfo_loongarch cpu_data[NR_CPUS] __read_mostly;
> > +
> > +EXPORT_SYMBOL(cpu_data);
> > +
> > +struct loongson_board_info b_info;
> > +static const char dmi_empty_string[] = " ";
> > +
> > +/*
> > + * Setup information
> > + *
> > + * These are initialized so they are in the .data section
> > + */
> > +
> > +char __initdata arcs_cmdline[COMMAND_LINE_SIZE];
> > +static char __initdata command_line[COMMAND_LINE_SIZE];
> > +
> > +static struct resource code_resource = { .name = "Kernel code", };
> > +static struct resource data_resource = { .name = "Kernel data", };
> > +static struct resource bss_resource = { .name = "Kernel bss", };
> > +
> > +const char *get_system_type(void)
> > +{
> > + return "generic-loongson-machine";
> > +}
> > +
> > +static const char *dmi_string_parse(const struct dmi_header *dm, u8 s)
> > +{
> > + const u8 *bp = ((u8 *) dm) + dm->length;
> > +
> > + if (s) {
> > + s--;
> > + while (s > 0 && *bp) {
> > + bp += strlen(bp) + 1;
> > + s--;
> > + }
> > +
> > + if (*bp != 0) {
> > + size_t len = strlen(bp)+1;
> > + size_t cmp_len = len > 8 ? 8 : len;
> > +
> > + if (!memcmp(bp, dmi_empty_string, cmp_len))
> > + return dmi_empty_string;
> > +
> > + return bp;
> > + }
> > + }
> > +
> > + return "";
> > +}
> > +
> > +static void __init parse_cpu_table(const struct dmi_header *dm)
> > +{
> > + long freq_temp = 0;
> > + char *dmi_data = (char *)dm;
> > +
> > + freq_temp = ((*(dmi_data + SMBIOS_FREQHIGH_OFFSET) << 8) +
> > + ((*(dmi_data + SMBIOS_FREQLOW_OFFSET)) & SMBIOS_FREQLOW_MASK));
> > + cpu_clock_freq = freq_temp * 1000000;
> > +
> > + loongson_sysconf.cpuname = (void *)dmi_string_parse(dm, dmi_data[16]);
> > + loongson_sysconf.cores_per_package = *(dmi_data + SMBIOS_CORE_PACKAGE_OFFSET);
> > +
> > + pr_info("CpuClock = %llu\n", cpu_clock_freq);
> > +}
> > +
> > +static void __init parse_bios_table(const struct dmi_header *dm)
> > +{
> > + int bios_extern;
> > + char *dmi_data = (char *)dm;
> > +
> > + bios_extern = *(dmi_data + SMBIOS_BIOSEXTERN_OFFSET);
> > + b_info.bios_size = *(dmi_data + SMBIOS_BIOSSIZE_OFFSET);
> > +
> > + if (bios_extern & LOONGSON_EFI_ENABLE)
> > + set_bit(EFI_BOOT, &efi.flags);
> > + else
> > + clear_bit(EFI_BOOT, &efi.flags);
> > +}
> > +
> > +static void __init find_tokens(const struct dmi_header *dm, void *dummy)
> > +{
> > + switch (dm->type) {
> > + case 0x0: /* Extern BIOS */
> > + parse_bios_table(dm);
> > + break;
> > + case 0x4: /* Calling interface */
> > + parse_cpu_table(dm);
> > + break;
> > + }
> > +}
> > +static void __init smbios_parse(void)
> > +{
> > + b_info.bios_vendor = (void *)dmi_get_system_info(DMI_BIOS_VENDOR);
> > + b_info.bios_version = (void *)dmi_get_system_info(DMI_BIOS_VERSION);
> > + b_info.bios_release_date = (void *)dmi_get_system_info(DMI_BIOS_DATE);
> > + b_info.board_vendor = (void *)dmi_get_system_info(DMI_BOARD_VENDOR);
> > + b_info.board_name = (void *)dmi_get_system_info(DMI_BOARD_NAME);
> > + dmi_walk(find_tokens, NULL);
> > +}
> > +
> > +/*
> > + * Manage initrd
> > + */
> > +#ifdef CONFIG_BLK_DEV_INITRD
> > +
> > +static unsigned long __init init_initrd(void)
> > +{
> > + if (!phys_initrd_start || !phys_initrd_size)
> > + goto disable;
> > +
> > + initrd_start = (unsigned long)phys_to_virt(phys_initrd_start);
> > + initrd_end = (unsigned long)phys_to_virt(phys_initrd_start + phys_initrd_size);
> > +
> > + if (!initrd_start || initrd_end <= initrd_start)
> > + goto disable;
> > +
> > + if (initrd_start & ~PAGE_MASK) {
> > + pr_err("initrd start must be page aligned\n");
> > + goto disable;
> > + }
> > + if (initrd_start < PAGE_OFFSET) {
> > + pr_err("initrd start < PAGE_OFFSET\n");
> > + goto disable;
> > + }
> > +
> > + ROOT_DEV = Root_RAM0;
> > +
> > + return 0;
> > +disable:
> > + initrd_start = 0;
> > + initrd_end = 0;
> > + return 0;
> > +}
> > +
> > +static void __init finalize_initrd(void)
> > +{
> > + unsigned long size = initrd_end - initrd_start;
> > +
> > + if (size == 0) {
> > + pr_info("Initrd not found or empty");
> > + goto disable;
> > + }
> > + if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
> > + pr_err("Initrd extends beyond end of memory");
> > + goto disable;
> > + }
> > +
> > +
> > + memblock_reserve(__pa(initrd_start), size);
> > + initrd_below_start_ok = 1;
> > +
> > + pr_info("Initial ramdisk at: 0x%lx (%lu bytes)\n",
> > + initrd_start, size);
> > + return;
> > +disable:
> > + pr_cont(" - disabling initrd\n");
> > + initrd_start = 0;
> > + initrd_end = 0;
> > +}
> > +
> > +#else /* !CONFIG_BLK_DEV_INITRD */
> > +
> > +static unsigned long __init init_initrd(void)
> > +{
> > + return 0;
> > +}
> > +
> > +#define finalize_initrd() do {} while (0)
> > +
> > +#endif
> > +
> > +static int usermem __initdata;
> > +
> > +static int __init early_parse_mem(char *p)
> > +{
> > + phys_addr_t start, size;
> > +
> > + /*
> > + * If a user specifies memory size, we
> > + * blow away any automatically generated
> > + * size.
> > + */
> > + if (usermem == 0) {
> > + usermem = 1;
> > + memblock_remove(memblock_start_of_DRAM(),
> > + memblock_end_of_DRAM() - memblock_start_of_DRAM());
> > + }
> > + start = 0;
> > + size = memparse(p, &p);
> > + if (*p == '@')
> > + start = memparse(p + 1, &p);
> > +
> > + memblock_add(start, size);
> > +
> > + return 0;
> > +}
> > +early_param("mem", early_parse_mem);
> > +
> > +static int __init early_parse_memmap(char *p)
> > +{
> > + char *oldp;
> > + u64 start_at, mem_size;
> > +
> > + if (!p)
> > + return -EINVAL;
> > +
> > + if (!strncmp(p, "exactmap", 8)) {
> > + pr_err("\"memmap=exactmap\" invalid on LoongArch\n");
> > + return 0;
> > + }
> > +
> > + oldp = p;
> > + mem_size = memparse(p, &p);
> > + if (p == oldp)
> > + return -EINVAL;
> > +
> > + if (*p == '@') {
> > + start_at = memparse(p+1, &p);
> > + memblock_add(start_at, mem_size);
> > + } else if (*p == '#') {
> > + pr_err("\"memmap=nn#ss\" (force ACPI data) invalid on LoongArch\n");
> > + return -EINVAL;
> > + } else if (*p == '$') {
> > + start_at = memparse(p+1, &p);
> > + memblock_add(start_at, mem_size);
> > + memblock_reserve(start_at, mem_size);
> > + } else {
> > + pr_err("\"memmap\" invalid format!\n");
> > + return -EINVAL;
> > + }
> > +
> > + if (*p == '\0') {
> > + usermem = 1;
> > + return 0;
> > + } else
> > + return -EINVAL;
> > +}
> > +early_param("memmap", early_parse_memmap);
> > +
> > +static void __init check_kernel_sections_mem(void)
> > +{
> > + phys_addr_t start = __pa_symbol(&_text);
> > + phys_addr_t size = __pa_symbol(&_end) - start;
> > +
> > + if (!memblock_is_region_memory(start, size)) {
> > + pr_info("Kernel sections are not in the memory maps\n");
> > + memblock_add(start, size);
> > + }
> > +}
> > +
> > +static void __init bootcmdline_append(const char *s, size_t max)
> > +{
> > + if (!s[0] || !max)
> > + return;
> > +
> > + if (boot_command_line[0])
> > + strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
> > +
> > + strlcat(boot_command_line, s, max);
> > +}
> > +
> > +static void __init bootcmdline_init(char **cmdline_p)
> > +{
> > + boot_command_line[0] = 0;
> > +
> > + /*
> > + * Take arguments from the bootloader at first. Early code should have
> > + * filled arcs_cmdline with arguments from the bootloader.
> > + */
> > + bootcmdline_append(arcs_cmdline, COMMAND_LINE_SIZE);
> > +
> > + strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
> > + *cmdline_p = command_line;
> > +
> > + parse_early_param();
> > +}
> > +
> > +/*
> > + * arch_mem_init - initialize memory management subsystem
> > + */
> > +static void __init arch_mem_init(char **cmdline_p)
> > +{
> > + if (usermem)
> > + pr_info("User-defined physical RAM map overwrite\n");
> > +
> > + check_kernel_sections_mem();
> > +
> > + memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
> > + pagetable_init();
> > +
> > + /*
> > + * Prevent memblock from allocating high memory.
> > + * This cannot be done before max_low_pfn is detected, so up
> > + * to this point is possible to only reserve physical memory
> > + * with memblock_reserve; memblock_alloc* can be used
> > + * only after this point
> > + */
> > + memblock_set_current_limit(PFN_PHYS(max_low_pfn));
> > +
> > + /*
> > + * In order to reduce the possibility of kernel panic when failed to
> > + * get IO TLB memory under CONFIG_SWIOTLB, it is better to allocate
> > + * low memory as small as possible before plat_swiotlb_setup(), so
> > + * make sparse_init() using top-down allocation.
> > + */
> > + memblock_set_bottom_up(false);
> > + sparse_init();
> > + memblock_set_bottom_up(true);
> > +
> > + swiotlb_init(1);
> > +
> > + dma_contiguous_reserve(PFN_PHYS(max_low_pfn));
> > +
> > + memblock_dump_all();
> > +
> > + early_memtest(PFN_PHYS(ARCH_PFN_OFFSET), PFN_PHYS(max_low_pfn));
> > +}
> > +
> > +static void __init resource_init(void)
> > +{
> > + u64 i;
> > + phys_addr_t start, end;
> > +
> > + code_resource.start = __pa_symbol(&_text);
> > + code_resource.end = __pa_symbol(&_etext) - 1;
> > + data_resource.start = __pa_symbol(&_etext);
> > + data_resource.end = __pa_symbol(&_edata) - 1;
> > + bss_resource.start = __pa_symbol(&__bss_start);
> > + bss_resource.end = __pa_symbol(&__bss_stop) - 1;
> > +
> > + for_each_mem_range(i, &start, &end) {
> > + struct resource *res;
> > +
> > + res = memblock_alloc(sizeof(struct resource), SMP_CACHE_BYTES);
> > + if (!res)
> > + panic("%s: Failed to allocate %zu bytes\n", __func__,
> > + sizeof(struct resource));
> > +
> > + res->start = start;
> > + /*
> > + * In memblock, end points to the first byte after the
> > + * range while in resourses, end points to the last byte in
> > + * the range.
> > + */
> > + res->end = end - 1;
> > + res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
> > + res->name = "System RAM";
> > +
> > + request_resource(&iomem_resource, res);
> > +
> > + /*
> > + * We don't know which RAM region contains kernel data,
> > + * so we try it repeatedly and let the resource manager
> > + * test it.
> > + */
> > + request_resource(res, &code_resource);
> > + request_resource(res, &data_resource);
> > + request_resource(res, &bss_resource);
> > + }
> > +}
> > +
> > +void __init platform_init(void)
> > +{
> > + efi_init();
> > +#ifdef CONFIG_ACPI_TABLE_UPGRADE
> > + acpi_table_upgrade();
> > +#endif
> > +#ifdef CONFIG_ACPI
> > + acpi_gbl_use_default_register_widths = false;
> > + acpi_boot_table_init();
> > + acpi_boot_init();
> > +#endif
> > +
> > + fw_init_memory();
> > + dmi_setup();
> > + smbios_parse();
> > + pr_info("The BIOS Version: %s\n", b_info.bios_version);
> > +
> > + efi_runtime_init();
> > +}
> > +
> > +void __init setup_arch(char **cmdline_p)
> > +{
> > + cpu_probe();
> > +
> > + fw_init_cmdline();
> > + fw_init_environ();
> > + early_memblock_init();
> > + bootcmdline_init(cmdline_p);
> > +
> > + init_initrd();
> > + platform_init();
> > + finalize_initrd();
> > +
> > + arch_mem_init(cmdline_p);
> > +
> > + resource_init();
> > +
> > + paging_init();
> > +}
> > +
> > +static int __init register_gop_device(void)
> > +{
> > + void *pd;
> > +
> > + if (screen_info.orig_video_isVGA != VIDEO_TYPE_EFI)
> > + return 0;
> > + pd = platform_device_register_data(NULL, "efi-framebuffer", 0,
> > + &screen_info, sizeof(screen_info));
> > + return PTR_ERR_OR_ZERO(pd);
> > +}
> > +subsys_initcall(register_gop_device);
> > diff --git a/arch/loongarch/kernel/time.c b/arch/loongarch/kernel/time.c
> > new file mode 100644
> > index 000000000000..2e00802a3742
> > --- /dev/null
> > +++ b/arch/loongarch/kernel/time.c
> > @@ -0,0 +1,237 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Common time service routines for LoongArch machines.
> > + *
> > + * Copyright (C) 2020-2021 Loongson Technology Corporation Limited
> > + */
> > +#include <linux/clockchips.h>
> > +#include <linux/delay.h>
> > +#include <linux/export.h>
> > +#include <linux/init.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/kernel.h>
> > +#include <linux/sched_clock.h>
> > +#include <linux/spinlock.h>
> > +
> > +#include <asm/cpu-features.h>
> > +#include <asm/loongarch.h>
> > +#include <asm/time.h>
> > +
> > +u64 cpu_clock_freq;
> > +EXPORT_SYMBOL(cpu_clock_freq);
> > +u64 const_clock_freq;
> > +EXPORT_SYMBOL(const_clock_freq);
> > +
> > +static DEFINE_RAW_SPINLOCK(state_lock);
> > +static DEFINE_PER_CPU(struct clock_event_device, constant_clockevent_device);
> > +
> > +static void constant_event_handler(struct clock_event_device *dev)
> > +{
> > +}
> > +
> > +irqreturn_t constant_timer_interrupt(int irq, void *data)
> > +{
> > + int cpu = smp_processor_id();
> > + struct clock_event_device *cd;
> > +
> > + /* Clear Timer Interrupt */
> > + write_csr_tintclear(CSR_TINTCLR_TI);
> > + cd = &per_cpu(constant_clockevent_device, cpu);
> > + cd->event_handler(cd);
> > +
> > + return IRQ_HANDLED;
> > +}
> > +
> > +static int constant_set_state_oneshot(struct clock_event_device *evt)
> > +{
> > + unsigned long timer_config;
> > +
> > + raw_spin_lock(&state_lock);
> > +
> > + timer_config = csr_readq(LOONGARCH_CSR_TCFG);
> > + timer_config |= CSR_TCFG_EN;
> > + timer_config &= ~CSR_TCFG_PERIOD;
> > + csr_writeq(timer_config, LOONGARCH_CSR_TCFG);
> > +
> > + raw_spin_unlock(&state_lock);
> > +
> > + return 0;
> > +}
> > +
> > +static int constant_set_state_oneshot_stopped(struct clock_event_device *evt)
> > +{
> > + unsigned long timer_config;
> > +
> > + raw_spin_lock(&state_lock);
> > +
> > + timer_config = csr_readq(LOONGARCH_CSR_TCFG);
> > + timer_config &= ~CSR_TCFG_EN;
> > + csr_writeq(timer_config, LOONGARCH_CSR_TCFG);
> > +
> > + raw_spin_unlock(&state_lock);
> > +
> > + return 0;
> > +}
> > +
> > +static int constant_set_state_periodic(struct clock_event_device *evt)
> > +{
> > + unsigned long period;
> > + unsigned long timer_config;
> > +
> > + raw_spin_lock(&state_lock);
> > +
> > + period = const_clock_freq / HZ;
> > + timer_config = period & CSR_TCFG_VAL;
> > + timer_config |= (CSR_TCFG_PERIOD | CSR_TCFG_EN);
> > + csr_writeq(timer_config, LOONGARCH_CSR_TCFG);
> > +
> > + raw_spin_unlock(&state_lock);
> > +
> > + return 0;
> > +}
> > +
> > +static int constant_set_state_shutdown(struct clock_event_device *evt)
> > +{
> > + return 0;
> > +}
> > +
> > +static int constant_timer_next_event(unsigned long delta, struct clock_event_device *evt)
> > +{
> > + unsigned long timer_config;
> > +
> > + delta &= CSR_TCFG_VAL;
> > + timer_config = delta | CSR_TCFG_EN;
> > + csr_writeq(timer_config, LOONGARCH_CSR_TCFG);
> > +
> > + return 0;
> > +}
> > +
> > +static unsigned long __init get_loops_per_jiffy(void)
> > +{
> > + unsigned long lpj = (unsigned long)const_clock_freq;
> > +
> > + do_div(lpj, HZ);
> > +
> > + return lpj;
> > +}
> > +
> > +static long init_timeval;
> > +
> > +void sync_counter(void)
> > +{
> > + /* Ensure counter begin at 0 */
> > + csr_writeq(-init_timeval, LOONGARCH_CSR_CNTC);
> > +}
> > +
> > +int constant_clockevent_init(void)
> > +{
> > + unsigned int irq;
> > + unsigned int cpu = smp_processor_id();
> > + unsigned long min_delta = 0x600;
> > + unsigned long max_delta = (1UL << 48) - 1;
> > + struct clock_event_device *cd;
> > + static int timer_irq_installed = 0;
> > +
> > + irq = get_timer_irq();
> > +
> > + cd = &per_cpu(constant_clockevent_device, cpu);
> > +
> > + cd->name = "Constant";
> > + cd->features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_PERCPU;
> > +
> > + cd->irq = irq;
> > + cd->rating = 320;
> > + cd->cpumask = cpumask_of(cpu);
> > + cd->set_state_oneshot = constant_set_state_oneshot;
> > + cd->set_state_oneshot_stopped = constant_set_state_oneshot_stopped;
> > + cd->set_state_periodic = constant_set_state_periodic;
> > + cd->set_state_shutdown = constant_set_state_shutdown;
> > + cd->set_next_event = constant_timer_next_event;
> > + cd->event_handler = constant_event_handler;
> > +
> > + clockevents_config_and_register(cd, const_clock_freq, min_delta, max_delta);
> > +
> > + if (timer_irq_installed)
> > + return 0;
> > +
> > + timer_irq_installed = 1;
> > +
> > + sync_counter();
> > +
> > + if (request_irq(irq, constant_timer_interrupt, IRQF_PERCPU | IRQF_TIMER, "timer", NULL))
> > + pr_err("Failed to request irq %d (timer)\n", irq);
> > +
> > + lpj_fine = get_loops_per_jiffy();
> > + pr_info("Constant clock event device register\n");
> > +
> > + return 0;
> > +}
> > +
> > +static u64 read_const_counter(struct clocksource *clk)
> > +{
> > + return drdtime();
> > +}
> > +
> > +static struct clocksource clocksource_const = {
> > + .name = "Constant",
> > + .rating = 400,
> > + .read = read_const_counter,
> > + .mask = CLOCKSOURCE_MASK(64),
> > + .flags = CLOCK_SOURCE_IS_CONTINUOUS,
> > + .mult = 0,
> > + .shift = 10,
> > +};
> > +
> > +unsigned long long notrace sched_clock(void)
> > +{
> > + /* 64-bit arithmetic can overflow, so use 128-bit. */
> > + u64 t1, t2, t3;
> > + unsigned long long rv;
> > + u64 mult = clocksource_const.mult;
> > + u64 shift = clocksource_const.shift;
> > + u64 cnt = read_const_counter(NULL);
> > +
> > + __asm__ (
> > + "nor %[t1], $r0, %[shift] \n\t"
> > + "mulh.du %[t2], %[cnt], %[mult] \n\t"
> > + "mul.d %[t3], %[cnt], %[mult] \n\t"
> > + "slli.d %[t2], %[t2], 1 \n\t"
> > + "srl.d %[rv], %[t3], %[shift] \n\t"
> > + "sll.d %[t1], %[t2], %[t1] \n\t"
> > + "or %[rv], %[t1], %[rv] \n\t"
> > + : [rv] "=&r" (rv), [t1] "=&r" (t1), [t2] "=&r" (t2), [t3] "=&r" (t3)
> > + : [cnt] "r" (cnt), [mult] "r" (mult), [shift] "r" (shift)
> > + : );
> > +
> > + return rv;
> > +}
> > +
> > +int __init constant_clocksource_init(void)
> > +{
> > + int res;
> > + unsigned long freq;
> > +
> > + freq = const_clock_freq;
> > +
> > + clocksource_const.mult =
> > + clocksource_hz2mult(freq, clocksource_const.shift);
> > +
> > + res = clocksource_register_hz(&clocksource_const, freq);
> > +
> > + pr_info("Constant clock source device register\n");
> > +
> > + return res;
> > +}
> > +
> > +void __init time_init(void)
> > +{
> > + if (!cpu_has_cpucfg)
> > + const_clock_freq = cpu_clock_freq;
> > + else
> > + const_clock_freq = calc_const_freq();
> > +
> > + init_timeval = drdtime() - csr_readq(LOONGARCH_CSR_CNTC);
> > +
> > + constant_clockevent_init();
> > + constant_clocksource_init();
> > +}
> > diff --git a/arch/loongarch/kernel/topology.c b/arch/loongarch/kernel/topology.c
> > new file mode 100644
> > index 000000000000..3b2cbb95875b
> > --- /dev/null
> > +++ b/arch/loongarch/kernel/topology.c
> > @@ -0,0 +1,13 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +#include <linux/cpu.h>
> > +#include <linux/init.h>
> > +#include <linux/percpu.h>
> > +
> > +static struct cpu cpu_device;
> > +
> > +static int __init topology_init(void)
> > +{
> > + return register_cpu(&cpu_device, 0);
> > +}
> > +
> > +subsys_initcall(topology_init);
> > --
> > 2.27.0
> >
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