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Message-ID: <2d1a4f3c-48b0-4105-bbc6-18d164512405@email.android.com>
Date: Mon, 06 Feb 2012 19:47:39 -0800
From: "hpanvin@...il.com" <hpa@...or.com>
To: Hitoshi Mitake <h.mitake@...il.com>, mingo@...e.hu
CC: linux-kernel@...r.kernel.org,
Hitoshi Mitake <mitake@....info.waseda.ac.jp>,
Kashyap Desai <Kashyap.Desai@....com>,
Len Brown <lenb@...nel.org>,
Ravi Anand <ravi.anand@...gic.com>,
Vikas Chaudhary <vikas.chaudhary@...gic.com>,
Matthew Garrett <mjg@...hat.com>,
Jason Uhlenkott <juhlenko@...mai.com>,
James Bottomley <James.Bottomley@...allels.com>,
Thomas Gleixner <tglx@...utronix.de>,
Roland Dreier <roland@...estorage.com>,
James Bottomley <jbottomley@...allels.com>,
Alan Cox <alan@...rguk.ukuu.org.uk>,
Matthew Wilcox <matthew.r.wilcox@...el.com>,
Andrew Morton <akpm@...ux-foundation.org>,
Linus Torvalds <torvalds@...ux-foundation.org>
Subject: Re: [PATCH] asm-generic: architecture independent readq/writeq for 32bit environment
Should be volatile u64 * not volatile void *...
Hitoshi Mitake <h.mitake@...il.com> wrote:
>From: Hitoshi Mitake <mitake@....info.waseda.ac.jp>
>
>This patch removes some readq()s in drivers (added in
>dbee8a0affd5e6eaa5d7c816)
>and provides unified readq()/writeq() for the drivers.
>
>For some people, readq/writeq without atomicity is harmful, and order
>of io
>access has to be specified explicitly. So in this patch, new two header
>files
>which contain non-atomic readq/writeq are added.
>io-64-nonatomic-lo-hi.h
>provides non-atomic readq/writeq with the order of lower address ->
>higher
>address. io-64-nonatomic-hi-lo.h provides non-atomic readq/writeq with
>reversed
>order. All of them are endian awared.
>
>If this patch is applied, the drivers which need readq/writeq must add
>the line:
>#include <asm-generic/io-64-nonatomic-lo-hi.h> /* or hi-lo.h */
>
>But this will be nop in 64-bit environments, and no other #ifdefs are
>required.
>So I believe that this patch can solve the problem of
>1. driver-specific readq/writeq
>2. atomicity and order of io access
>
>This patch is tested with building allyesconfig and allmodconfig as
>ARCH=x86 and
>ARCH=i386 on top of tip/master.
>
>Cc: Kashyap Desai <Kashyap.Desai@....com>
>Cc: Len Brown <lenb@...nel.org>
>Cc: Ravi Anand <ravi.anand@...gic.com>
>Cc: Vikas Chaudhary <vikas.chaudhary@...gic.com>
>Cc: Matthew Garrett <mjg@...hat.com>
>Cc: Jason Uhlenkott <juhlenko@...mai.com>
>Cc: James Bottomley <James.Bottomley@...allels.com>
>Cc: Thomas Gleixner <tglx@...utronix.de>
>Cc: "H. Peter Anvin" <hpa@...or.com>
>Cc: Roland Dreier <roland@...estorage.com>
>Cc: James Bottomley <jbottomley@...allels.com>
>Cc: Alan Cox <alan@...rguk.ukuu.org.uk>
>Cc: Matthew Wilcox <matthew.r.wilcox@...el.com>
>Cc: Andrew Morton <akpm@...ux-foundation.org>
>Cc: Linus Torvalds <torvalds@...ux-foundation.org>
>Signed-off-by: Hitoshi Mitake <h.mitake@...il.com>
>
>---
> drivers/edac/i3200_edac.c | 15 +------
> drivers/platform/x86/ibm_rtl.c | 15 +------
> drivers/platform/x86/intel_ips.c | 15 +------
> drivers/scsi/qla4xxx/ql4_nx.c | 23 +---------
>include/asm-generic/io-64-nonatomic-hi-lo.h | 63
>+++++++++++++++++++++++++++
>include/asm-generic/io-64-nonatomic-lo-hi.h | 63
>+++++++++++++++++++++++++++
> 6 files changed, 134 insertions(+), 60 deletions(-)
> create mode 100644 include/asm-generic/io-64-nonatomic-hi-lo.h
> create mode 100644 include/asm-generic/io-64-nonatomic-lo-hi.h
>
>diff --git a/drivers/edac/i3200_edac.c b/drivers/edac/i3200_edac.c
>index aa08497..73f55e200 100644
>--- a/drivers/edac/i3200_edac.c
>+++ b/drivers/edac/i3200_edac.c
>@@ -15,6 +15,8 @@
> #include <linux/io.h>
> #include "edac_core.h"
>
>+#include <asm-generic/io-64-nonatomic-lo-hi.h>
>+
> #define I3200_REVISION "1.1"
>
> #define EDAC_MOD_STR "i3200_edac"
>@@ -101,19 +103,6 @@ struct i3200_priv {
>
> static int nr_channels;
>
>-#ifndef readq
>-static inline __u64 readq(const volatile void __iomem *addr)
>-{
>- const volatile u32 __iomem *p = addr;
>- u32 low, high;
>-
>- low = readl(p);
>- high = readl(p + 1);
>-
>- return low + ((u64)high << 32);
>-}
>-#endif
>-
> static int how_many_channels(struct pci_dev *pdev)
> {
> unsigned char capid0_8b; /* 8th byte of CAPID0 */
>diff --git a/drivers/platform/x86/ibm_rtl.c
>b/drivers/platform/x86/ibm_rtl.c
>index 42a7d60..7481146 100644
>--- a/drivers/platform/x86/ibm_rtl.c
>+++ b/drivers/platform/x86/ibm_rtl.c
>@@ -33,6 +33,8 @@
> #include <linux/mutex.h>
> #include <asm/bios_ebda.h>
>
>+#include <asm-generic/io-64-nonatomic-lo-hi.h>
>+
> static bool force;
> module_param(force, bool, 0);
> MODULE_PARM_DESC(force, "Force driver load, ignore DMI data");
>@@ -83,19 +85,6 @@ static void __iomem *rtl_cmd_addr;
> static u8 rtl_cmd_type;
> static u8 rtl_cmd_width;
>
>-#ifndef readq
>-static inline __u64 readq(const volatile void __iomem *addr)
>-{
>- const volatile u32 __iomem *p = addr;
>- u32 low, high;
>-
>- low = readl(p);
>- high = readl(p + 1);
>-
>- return low + ((u64)high << 32);
>-}
>-#endif
>-
> static void __iomem *rtl_port_map(phys_addr_t addr, unsigned long len)
> {
> if (rtl_cmd_type == RTL_ADDR_TYPE_MMIO)
>diff --git a/drivers/platform/x86/intel_ips.c
>b/drivers/platform/x86/intel_ips.c
>index 809a3ae..88a98cf 100644
>--- a/drivers/platform/x86/intel_ips.c
>+++ b/drivers/platform/x86/intel_ips.c
>@@ -77,6 +77,8 @@
> #include <asm/processor.h>
> #include "intel_ips.h"
>
>+#include <asm-generic/io-64-nonatomic-lo-hi.h>
>+
> #define PCI_DEVICE_ID_INTEL_THERMAL_SENSOR 0x3b32
>
> /*
>@@ -344,19 +346,6 @@ struct ips_driver {
> static bool
> ips_gpu_turbo_enabled(struct ips_driver *ips);
>
>-#ifndef readq
>-static inline __u64 readq(const volatile void __iomem *addr)
>-{
>- const volatile u32 __iomem *p = addr;
>- u32 low, high;
>-
>- low = readl(p);
>- high = readl(p + 1);
>-
>- return low + ((u64)high << 32);
>-}
>-#endif
>-
> /**
> * ips_cpu_busy - is CPU busy?
> * @ips: IPS driver struct
>diff --git a/drivers/scsi/qla4xxx/ql4_nx.c
>b/drivers/scsi/qla4xxx/ql4_nx.c
>index 78f1111..65253df 100644
>--- a/drivers/scsi/qla4xxx/ql4_nx.c
>+++ b/drivers/scsi/qla4xxx/ql4_nx.c
>@@ -10,6 +10,8 @@
> #include "ql4_def.h"
> #include "ql4_glbl.h"
>
>+#include <asm-generic/io-64-nonatomic-lo-hi.h>
>+
> #define MASK(n) DMA_BIT_MASK(n)
>#define MN_WIN(addr) (((addr & 0x1fc0000) >> 1) | ((addr >> 25) &
>0x3ff))
>#define OCM_WIN(addr) (((addr & 0x1ff0000) >> 1) | ((addr >> 25) &
>0x3ff))
>@@ -655,27 +657,6 @@ static int qla4_8xxx_pci_is_same_window(struct
>scsi_qla_host *ha,
> return 0;
> }
>
>-#ifndef readq
>-static inline __u64 readq(const volatile void __iomem *addr)
>-{
>- const volatile u32 __iomem *p = addr;
>- u32 low, high;
>-
>- low = readl(p);
>- high = readl(p + 1);
>-
>- return low + ((u64)high << 32);
>-}
>-#endif
>-
>-#ifndef writeq
>-static inline void writeq(__u64 val, volatile void __iomem *addr)
>-{
>- writel(val, addr);
>- writel(val >> 32, addr+4);
>-}
>-#endif
>-
> static int qla4_8xxx_pci_mem_read_direct(struct scsi_qla_host *ha,
> u64 off, void *data, int size)
> {
>diff --git a/include/asm-generic/io-64-nonatomic-hi-lo.h
>b/include/asm-generic/io-64-nonatomic-hi-lo.h
>new file mode 100644
>index 0000000..34e61cc
>--- /dev/null
>+++ b/include/asm-generic/io-64-nonatomic-hi-lo.h
>@@ -0,0 +1,63 @@
>+#ifndef _ASM_IO_64_NONATOMIC_HI_LO_H_
>+#define _ASM_IO_64_NONATOMIC_HI_LO_H_
>+
>+#include <linux/io.h>
>+#include <asm-generic/int-ll64.h>
>+
>+#ifdef CPU_LITTLE_ENDIAN
>+
>+#ifndef readq
>+
>+static inline __u64 readq(const volatile void __iomem *addr)
>+{
>+ const volatile u32 __iomem *p = addr;
>+ u32 low, high;
>+
>+ high = readl(p + 1);
>+ low = readl(p);
>+
>+ return low + ((u64)high << 32);
>+}
>+
>+#endif
>+
>+#ifndef writeq
>+
>+static inline void writeq(__u64 val, volatile void __iomem *addr)
>+{
>+ writel(val >> 32, addr + 4);
>+ writel(val, addr);
>+}
>+
>+#endif
>+
>+#else /* big endian */
>+
>+#ifndef readq
>+
>+static inline __u64 readq(const volatile void __iomem *addr)
>+{
>+ const volatile u32 __iomem *p = addr;
>+ u32 low, high;
>+
>+ low = readl(p + 1);
>+ high = readl(p);
>+
>+ return low + ((u64)high << 32);
>+}
>+
>+#endif
>+
>+#ifndef writeq
>+
>+static inline void writeq(__u64 val, volatile void __iomem *addr)
>+{
>+ writel(val >> 32, addr);
>+ writel(val, addr + 4);
>+}
>+
>+#endif
>+
>+#endif
>+
>+#endif /* _ASM_IO_64_NONATOMIC_HI_LO_H_ */
>diff --git a/include/asm-generic/io-64-nonatomic-lo-hi.h
>b/include/asm-generic/io-64-nonatomic-lo-hi.h
>new file mode 100644
>index 0000000..bf2fe0f
>--- /dev/null
>+++ b/include/asm-generic/io-64-nonatomic-lo-hi.h
>@@ -0,0 +1,63 @@
>+#ifndef _ASM_IO_64_NONATOMIC_LO_HI_H_
>+#define _ASM_IO_64_NONATOMIC_LO_HI_H_
>+
>+#include <linux/io.h>
>+#include <asm-generic/int-ll64.h>
>+
>+#ifdef CPU_LITTLE_ENDIAN
>+
>+#ifndef readq
>+
>+static inline __u64 readq(const volatile void __iomem *addr)
>+{
>+ const volatile u32 __iomem *p = addr;
>+ u32 low, high;
>+
>+ low = readl(p);
>+ high = readl(p + 1);
>+
>+ return low + ((u64)high << 32);
>+}
>+
>+#endif
>+
>+#ifndef writeq
>+
>+static inline void writeq(__u64 val, volatile void __iomem *addr)
>+{
>+ writel(val, addr);
>+ writel(val >> 32, addr + 4);
>+}
>+
>+#endif
>+
>+#else /* big endian */
>+
>+#ifndef readq
>+
>+static inline __u64 readq(const volatile void __iomem *addr)
>+{
>+ const volatile u32 __iomem *p = addr;
>+ u32 low, high;
>+
>+ high = readl(p);
>+ low = readl(p + 1);
>+
>+ return low + ((u64)high << 32);
>+}
>+
>+#endif
>+
>+#ifndef writeq
>+
>+static inline void writeq(__u64 val, volatile void __iomem *addr)
>+{
>+ writel(val, addr + 4);
>+ writel(val >> 32, addr);
>+}
>+
>+#endif
>+
>+#endif
>+
>+#endif /* _ASM_IO_64_NONATOMIC_LO_HI_H_ */
>--
>1.7.5.1
--
Sent from my Android phone with K-9 Mail. Please excuse my brevity.
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