From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip! --- arch/i386/pci/mmconfig.c | 122 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 122 insertions(+) create mode 100644 arch/i386/pci/mmconfig.c (limited to 'arch/i386/pci/mmconfig.c') diff --git a/arch/i386/pci/mmconfig.c b/arch/i386/pci/mmconfig.c new file mode 100644 index 000000000000..021a50aa51f4 --- /dev/null +++ b/arch/i386/pci/mmconfig.c @@ -0,0 +1,122 @@ +/* + * Copyright (C) 2004 Matthew Wilcox + * Copyright (C) 2004 Intel Corp. + * + * This code is released under the GNU General Public License version 2. + */ + +/* + * mmconfig.c - Low-level direct PCI config space access via MMCONFIG + */ + +#include +#include +#include "pci.h" + +/* The physical address of the MMCONFIG aperture. Set from ACPI tables. */ +u32 pci_mmcfg_base_addr; + +#define mmcfg_virt_addr ((void __iomem *) fix_to_virt(FIX_PCIE_MCFG)) + +/* The base address of the last MMCONFIG device accessed */ +static u32 mmcfg_last_accessed_device; + +/* + * Functions for accessing PCI configuration space with MMCONFIG accesses + */ + +static inline void pci_exp_set_dev_base(int bus, int devfn) +{ + u32 dev_base = pci_mmcfg_base_addr | (bus << 20) | (devfn << 12); + if (dev_base != mmcfg_last_accessed_device) { + mmcfg_last_accessed_device = dev_base; + set_fixmap_nocache(FIX_PCIE_MCFG, dev_base); + } +} + +static int pci_mmcfg_read(unsigned int seg, unsigned int bus, + unsigned int devfn, int reg, int len, u32 *value) +{ + unsigned long flags; + + if (!value || (bus > 255) || (devfn > 255) || (reg > 4095)) + return -EINVAL; + + spin_lock_irqsave(&pci_config_lock, flags); + + pci_exp_set_dev_base(bus, devfn); + + switch (len) { + case 1: + *value = readb(mmcfg_virt_addr + reg); + break; + case 2: + *value = readw(mmcfg_virt_addr + reg); + break; + case 4: + *value = readl(mmcfg_virt_addr + reg); + break; + } + + spin_unlock_irqrestore(&pci_config_lock, flags); + + return 0; +} + +static int pci_mmcfg_write(unsigned int seg, unsigned int bus, + unsigned int devfn, int reg, int len, u32 value) +{ + unsigned long flags; + + if ((bus > 255) || (devfn > 255) || (reg > 4095)) + return -EINVAL; + + spin_lock_irqsave(&pci_config_lock, flags); + + pci_exp_set_dev_base(bus, devfn); + + switch (len) { + case 1: + writeb(value, mmcfg_virt_addr + reg); + break; + case 2: + writew(value, mmcfg_virt_addr + reg); + break; + case 4: + writel(value, mmcfg_virt_addr + reg); + break; + } + + spin_unlock_irqrestore(&pci_config_lock, flags); + + return 0; +} + +static struct pci_raw_ops pci_mmcfg = { + .read = pci_mmcfg_read, + .write = pci_mmcfg_write, +}; + +static int __init pci_mmcfg_init(void) +{ + if ((pci_probe & PCI_PROBE_MMCONF) == 0) + goto out; + if (!pci_mmcfg_base_addr) + goto out; + + /* Kludge for now. Don't use mmconfig on AMD systems because + those have some busses where mmconfig doesn't work, + and we don't parse ACPI MCFG well enough to handle that. + Remove when proper handling is added. */ + if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) + goto out; + + printk(KERN_INFO "PCI: Using MMCONFIG\n"); + raw_pci_ops = &pci_mmcfg; + pci_probe = (pci_probe & ~PCI_PROBE_MASK) | PCI_PROBE_MMCONF; + + out: + return 0; +} + +arch_initcall(pci_mmcfg_init); -- cgit v1.2.2