>From fc1e24786c764bf7e7a73128f839b58a0559739c Mon Sep 17 00:00:00 2001 From: Ivan Kokshaysky Date: Mon, 14 Jan 2008 17:31:09 -0500 Subject: [PATCH] PCI x86: always use conf1 to access config space below 256 bytes Thanks to Loic Prylli , who originally proposed this idea. Always using legacy configuration mechanism for the legacy config space and extended mechanism (mmconf) for the extended config space is a simple and very logical approach. It's supposed to resolve all known mmconf problems. It still allows per-device quirks (tweaking dev->cfg_size). It also allows to get rid of mmconf fallback code. Signed-off-by: Ivan Kokshaysky Signed-off-by: Matthew Wilcox --- arch/x86/pci/mmconfig-shared.c | 35 ----------------------------------- arch/x86/pci/mmconfig_32.c | 22 +++++++++------------- arch/x86/pci/mmconfig_64.c | 22 ++++++++++------------ arch/x86/pci/pci.h | 7 ------- 4 files changed, 19 insertions(+), 67 deletions(-) diff --git a/arch/x86/pci/mmconfig-shared.c b/arch/x86/pci/mmconfig-shared.c index 4df637e..6b521d3 100644 --- a/arch/x86/pci/mmconfig-shared.c +++ b/arch/x86/pci/mmconfig-shared.c @@ -22,42 +22,9 @@ #define MMCONFIG_APER_MIN (2 * 1024*1024) #define MMCONFIG_APER_MAX (256 * 1024*1024) -DECLARE_BITMAP(pci_mmcfg_fallback_slots, 32*PCI_MMCFG_MAX_CHECK_BUS); - /* Indicate if the mmcfg resources have been placed into the resource table. */ static int __initdata pci_mmcfg_resources_inserted; -/* K8 systems have some devices (typically in the builtin northbridge) - that are only accessible using type1 - Normally this can be expressed in the MCFG by not listing them - and assigning suitable _SEGs, but this isn't implemented in some BIOS. - Instead try to discover all devices on bus 0 that are unreachable using MM - and fallback for them. */ -static void __init unreachable_devices(void) -{ - int i, bus; - /* Use the max bus number from ACPI here? */ - for (bus = 0; bus < PCI_MMCFG_MAX_CHECK_BUS; bus++) { - for (i = 0; i < 32; i++) { - unsigned int devfn = PCI_DEVFN(i, 0); - u32 val1, val2; - - pci_conf1_read(0, bus, devfn, 0, 4, &val1); - if (val1 == 0xffffffff) - continue; - - if (pci_mmcfg_arch_reachable(0, bus, devfn)) { - raw_pci_ops->read(0, bus, devfn, 0, 4, &val2); - if (val1 == val2) - continue; - } - set_bit(i + 32 * bus, pci_mmcfg_fallback_slots); - printk(KERN_NOTICE "PCI: No mmconfig possible on device" - " %02x:%02x\n", bus, i); - } - } -} - static const char __init *pci_mmcfg_e7520(void) { u32 win; @@ -270,8 +237,6 @@ void __init pci_mmcfg_init(int type) return; if (pci_mmcfg_arch_init()) { - if (type == 1) - unreachable_devices(); if (known_bridge) pci_mmcfg_insert_resources(IORESOURCE_BUSY); pci_probe = (pci_probe & ~PCI_PROBE_MASK) | PCI_PROBE_MMCONF; diff --git a/arch/x86/pci/mmconfig_32.c b/arch/x86/pci/mmconfig_32.c index 1bf5816..7b75e65 100644 --- a/arch/x86/pci/mmconfig_32.c +++ b/arch/x86/pci/mmconfig_32.c @@ -30,10 +30,6 @@ static u32 get_base_addr(unsigned int seg, int bus, unsigned devfn) struct acpi_mcfg_allocation *cfg; int cfg_num; - if (seg == 0 && bus < PCI_MMCFG_MAX_CHECK_BUS && - test_bit(PCI_SLOT(devfn) + 32*bus, pci_mmcfg_fallback_slots)) - return 0; - for (cfg_num = 0; cfg_num < pci_mmcfg_config_num; cfg_num++) { cfg = &pci_mmcfg_config[cfg_num]; if (cfg->pci_segment == seg && @@ -68,13 +64,16 @@ static int pci_mmcfg_read(unsigned int seg, unsigned int bus, u32 base; if ((bus > 255) || (devfn > 255) || (reg > 4095)) { - *value = -1; +err: *value = -1; return -EINVAL; } + if (reg < 256) + return pci_conf1_read(seg,bus,devfn,reg,len,value); + base = get_base_addr(seg, bus, devfn); if (!base) - return pci_conf1_read(seg,bus,devfn,reg,len,value); + goto err; spin_lock_irqsave(&pci_config_lock, flags); @@ -105,9 +104,12 @@ static int pci_mmcfg_write(unsigned int seg, unsigned int bus, if ((bus > 255) || (devfn > 255) || (reg > 4095)) return -EINVAL; + if (reg < 256) + return pci_conf1_write(seg,bus,devfn,reg,len,value); + base = get_base_addr(seg, bus, devfn); if (!base) - return pci_conf1_write(seg,bus,devfn,reg,len,value); + return -EINVAL; spin_lock_irqsave(&pci_config_lock, flags); @@ -134,12 +136,6 @@ static struct pci_raw_ops pci_mmcfg = { .write = pci_mmcfg_write, }; -int __init pci_mmcfg_arch_reachable(unsigned int seg, unsigned int bus, - unsigned int devfn) -{ - return get_base_addr(seg, bus, devfn) != 0; -} - int __init pci_mmcfg_arch_init(void) { printk(KERN_INFO "PCI: Using MMCONFIG\n"); diff --git a/arch/x86/pci/mmconfig_64.c b/arch/x86/pci/mmconfig_64.c index 4095e4d..c4cf318 100644 --- a/arch/x86/pci/mmconfig_64.c +++ b/arch/x86/pci/mmconfig_64.c @@ -40,9 +40,7 @@ static char __iomem *get_virt(unsigned int seg, unsigned bus) static char __iomem *pci_dev_base(unsigned int seg, unsigned int bus, unsigned int devfn) { char __iomem *addr; - if (seg == 0 && bus < PCI_MMCFG_MAX_CHECK_BUS && - test_bit(32*bus + PCI_SLOT(devfn), pci_mmcfg_fallback_slots)) - return NULL; + addr = get_virt(seg, bus); if (!addr) return NULL; @@ -56,13 +54,16 @@ static int pci_mmcfg_read(unsigned int seg, unsigned int bus, /* Why do we have this when nobody checks it. How about a BUG()!? -AK */ if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095))) { - *value = -1; +err: *value = -1; return -EINVAL; } + if (reg < 256) + return pci_conf1_read(seg,bus,devfn,reg,len,value); + addr = pci_dev_base(seg, bus, devfn); if (!addr) - return pci_conf1_read(seg,bus,devfn,reg,len,value); + goto err; switch (len) { case 1: @@ -88,9 +89,12 @@ static int pci_mmcfg_write(unsigned int seg, unsigned int bus, if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095))) return -EINVAL; + if (reg < 256) + return pci_conf1_write(seg,bus,devfn,reg,len,value); + addr = pci_dev_base(seg, bus, devfn); if (!addr) - return pci_conf1_write(seg,bus,devfn,reg,len,value); + return -EINVAL; switch (len) { case 1: @@ -126,12 +130,6 @@ static void __iomem * __init mcfg_ioremap(struct acpi_mcfg_allocation *cfg) return addr; } -int __init pci_mmcfg_arch_reachable(unsigned int seg, unsigned int bus, - unsigned int devfn) -{ - return pci_dev_base(seg, bus, devfn) != NULL; -} - int __init pci_mmcfg_arch_init(void) { int i; diff --git a/arch/x86/pci/pci.h b/arch/x86/pci/pci.h index ac56d39..36cb44c 100644 --- a/arch/x86/pci/pci.h +++ b/arch/x86/pci/pci.h @@ -98,13 +98,6 @@ extern void pcibios_sort(void); /* pci-mmconfig.c */ -/* Verify the first 16 busses. We assume that systems with more busses - get MCFG right. */ -#define PCI_MMCFG_MAX_CHECK_BUS 16 -extern DECLARE_BITMAP(pci_mmcfg_fallback_slots, 32*PCI_MMCFG_MAX_CHECK_BUS); - -extern int __init pci_mmcfg_arch_reachable(unsigned int seg, unsigned int bus, - unsigned int devfn); extern int __init pci_mmcfg_arch_init(void); /* -- 1.5.2.5