diff options
Diffstat (limited to 'arch/x86/pci/pcbios.c')
| -rw-r--r-- | arch/x86/pci/pcbios.c | 31 |
1 files changed, 28 insertions, 3 deletions
diff --git a/arch/x86/pci/pcbios.c b/arch/x86/pci/pcbios.c index 2492d165096..c77b24a8b2d 100644 --- a/arch/x86/pci/pcbios.c +++ b/arch/x86/pci/pcbios.c @@ -9,6 +9,7 @@ #include <linux/uaccess.h> #include <asm/pci_x86.h> #include <asm/pci-functions.h> +#include <asm/cacheflush.h> /* BIOS32 signature: "_32_" */ #define BIOS32_SIGNATURE (('_' << 0) + ('3' << 8) + ('2' << 16) + ('_' << 24)) @@ -25,6 +26,27 @@ #define PCIBIOS_HW_TYPE1_SPEC 0x10 #define PCIBIOS_HW_TYPE2_SPEC 0x20 +int pcibios_enabled; + +/* According to the BIOS specification at: + * http://members.datafast.net.au/dft0802/specs/bios21.pdf, we could + * restrict the x zone to some pages and make it ro. But this may be + * broken on some bios, complex to handle with static_protections. + * We could make the 0xe0000-0x100000 range rox, but this can break + * some ISA mapping. + * + * So we let's an rw and x hole when pcibios is used. This shouldn't + * happen for modern system with mmconfig, and if you don't want it + * you could disable pcibios... + */ +static inline void set_bios_x(void) +{ + pcibios_enabled = 1; + set_memory_x(PAGE_OFFSET + BIOS_BEGIN, (BIOS_END - BIOS_BEGIN) >> PAGE_SHIFT); + if (__supported_pte_mask & _PAGE_NX) + printk(KERN_INFO "PCI : PCI BIOS area is rw and x. Use pci=nobios if you want it NX.\n"); +} + /* * This is the standard structure used to identify the entry point * to the BIOS32 Service Directory, as documented in @@ -102,7 +124,7 @@ static struct { static int pci_bios_present; -static int __devinit check_pcibios(void) +static int check_pcibios(void) { u32 signature, eax, ebx, ecx; u8 status, major_ver, minor_ver, hw_mech; @@ -159,6 +181,7 @@ static int pci_bios_read(unsigned int seg, unsigned int bus, unsigned long flags; unsigned long bx = (bus << 8) | devfn; + WARN_ON(seg); if (!value || (bus > 255) || (devfn > 255) || (reg > 255)) return -EINVAL; @@ -225,6 +248,7 @@ static int pci_bios_write(unsigned int seg, unsigned int bus, unsigned long flags; unsigned long bx = (bus << 8) | devfn; + WARN_ON(seg); if ((bus > 255) || (devfn > 255) || (reg > 255)) return -EINVAL; @@ -279,7 +303,7 @@ static int pci_bios_write(unsigned int seg, unsigned int bus, * Function table for BIOS32 access */ -static struct pci_raw_ops pci_bios_access = { +static const struct pci_raw_ops pci_bios_access = { .read = pci_bios_read, .write = pci_bios_write }; @@ -288,7 +312,7 @@ static struct pci_raw_ops pci_bios_access = { * Try to find PCI BIOS. */ -static struct pci_raw_ops * __devinit pci_find_bios(void) +static const struct pci_raw_ops *pci_find_bios(void) { union bios32 *check; unsigned char sum; @@ -332,6 +356,7 @@ static struct pci_raw_ops * __devinit pci_find_bios(void) DBG("PCI: BIOS32 Service Directory entry at 0x%lx\n", bios32_entry); bios32_indirect.address = bios32_entry + PAGE_OFFSET; + set_bios_x(); if (check_pcibios()) return &pci_bios_access; } |