linux/arch/x86/kernel/efi_64.c
Paul Mackerras 6a7bbd57ed x86: Make 64-bit efi_ioremap use ioremap on MMIO regions
Booting current 64-bit x86 kernels on the latest Apple MacBook
(MacBook5,2) via EFI gives the following warning:

[    0.182209] ------------[ cut here ]------------
[    0.182222] WARNING: at arch/x86/mm/pageattr.c:581 __cpa_process_fault+0x44/0xa0()
[    0.182227] Hardware name: MacBook5,2
[    0.182231] CPA: called for zero pte. vaddr = ffff8800ffe00000 cpa->vaddr = ffff8800ffe00000
[    0.182236] Modules linked in:
[    0.182242] Pid: 0, comm: swapper Not tainted 2.6.31-rc4 #6
[    0.182246] Call Trace:
[    0.182254]  [<ffffffff8102c754>] ? __cpa_process_fault+0x44/0xa0
[    0.182261]  [<ffffffff81048668>] warn_slowpath_common+0x78/0xd0
[    0.182266]  [<ffffffff81048744>] warn_slowpath_fmt+0x64/0x70
[    0.182272]  [<ffffffff8102c7ec>] ? update_page_count+0x3c/0x50
[    0.182280]  [<ffffffff818d25c5>] ? phys_pmd_init+0x140/0x22e
[    0.182286]  [<ffffffff8102c754>] __cpa_process_fault+0x44/0xa0
[    0.182292]  [<ffffffff8102ce60>] __change_page_attr_set_clr+0x5f0/0xb40
[    0.182301]  [<ffffffff810d1035>] ? vm_unmap_aliases+0x175/0x190
[    0.182307]  [<ffffffff8102d4ae>] change_page_attr_set_clr+0xfe/0x3d0
[    0.182314]  [<ffffffff8102dcca>] _set_memory_uc+0x2a/0x30
[    0.182319]  [<ffffffff8102dd4b>] set_memory_uc+0x7b/0xb0
[    0.182327]  [<ffffffff818afe31>] efi_enter_virtual_mode+0x2ad/0x2c9
[    0.182334]  [<ffffffff818a1c66>] start_kernel+0x2db/0x3f4
[    0.182340]  [<ffffffff818a1289>] x86_64_start_reservations+0x99/0xb9
[    0.182345]  [<ffffffff818a1389>] x86_64_start_kernel+0xe0/0xf2
[    0.182357] ---[ end trace 4eaa2a86a8e2da22 ]---
[    0.182982] init_memory_mapping: 00000000ffffc000-0000000100000000
[    0.182993]  00ffffc000 - 0100000000 page 4k

This happens because the 64-bit version of efi_ioremap calls
init_memory_mapping for all addresses, regardless of whether they are
RAM or MMIO.  The EFI tables on this machine ask for runtime access to
some MMIO regions:

[    0.000000] EFI: mem195: type=11, attr=0x8000000000000000, range=[0x0000000093400000-0x0000000093401000) (0MB)
[    0.000000] EFI: mem196: type=11, attr=0x8000000000000000, range=[0x00000000ffc00000-0x00000000ffc40000) (0MB)
[    0.000000] EFI: mem197: type=11, attr=0x8000000000000000, range=[0x00000000ffc40000-0x00000000ffc80000) (0MB)
[    0.000000] EFI: mem198: type=11, attr=0x8000000000000000, range=[0x00000000ffc80000-0x00000000ffca4000) (0MB)
[    0.000000] EFI: mem199: type=11, attr=0x8000000000000000, range=[0x00000000ffca4000-0x00000000ffcb4000) (0MB)
[    0.000000] EFI: mem200: type=11, attr=0x8000000000000000, range=[0x00000000ffcb4000-0x00000000ffffc000) (3MB)
[    0.000000] EFI: mem201: type=11, attr=0x8000000000000000, range=[0x00000000ffffc000-0x0000000100000000) (0MB)

This arranges to pass the EFI memory type through to efi_ioremap, and
makes efi_ioremap use ioremap rather than init_memory_mapping if the
type is EFI_MEMORY_MAPPED_IO.  With this, the above warning goes away.

Signed-off-by: Paul Mackerras <paulus@samba.org>
LKML-Reference: <19062.55858.533494.471153@cargo.ozlabs.ibm.com>
Cc: Huang Ying <ying.huang@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-08-03 13:34:25 -07:00

115 lines
2.9 KiB
C

/*
* x86_64 specific EFI support functions
* Based on Extensible Firmware Interface Specification version 1.0
*
* Copyright (C) 2005-2008 Intel Co.
* Fenghua Yu <fenghua.yu@intel.com>
* Bibo Mao <bibo.mao@intel.com>
* Chandramouli Narayanan <mouli@linux.intel.com>
* Huang Ying <ying.huang@intel.com>
*
* Code to convert EFI to E820 map has been implemented in elilo bootloader
* based on a EFI patch by Edgar Hucek. Based on the E820 map, the page table
* is setup appropriately for EFI runtime code.
* - mouli 06/14/2007.
*
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/types.h>
#include <linux/spinlock.h>
#include <linux/bootmem.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/efi.h>
#include <linux/uaccess.h>
#include <linux/io.h>
#include <linux/reboot.h>
#include <asm/setup.h>
#include <asm/page.h>
#include <asm/e820.h>
#include <asm/pgtable.h>
#include <asm/tlbflush.h>
#include <asm/proto.h>
#include <asm/efi.h>
#include <asm/cacheflush.h>
#include <asm/fixmap.h>
static pgd_t save_pgd __initdata;
static unsigned long efi_flags __initdata;
static void __init early_mapping_set_exec(unsigned long start,
unsigned long end,
int executable)
{
unsigned long num_pages;
start &= PMD_MASK;
end = (end + PMD_SIZE - 1) & PMD_MASK;
num_pages = (end - start) >> PAGE_SHIFT;
if (executable)
set_memory_x((unsigned long)__va(start), num_pages);
else
set_memory_nx((unsigned long)__va(start), num_pages);
}
static void __init early_runtime_code_mapping_set_exec(int executable)
{
efi_memory_desc_t *md;
void *p;
if (!(__supported_pte_mask & _PAGE_NX))
return;
/* Make EFI runtime service code area executable */
for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
md = p;
if (md->type == EFI_RUNTIME_SERVICES_CODE) {
unsigned long end;
end = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT);
early_mapping_set_exec(md->phys_addr, end, executable);
}
}
}
void __init efi_call_phys_prelog(void)
{
unsigned long vaddress;
early_runtime_code_mapping_set_exec(1);
local_irq_save(efi_flags);
vaddress = (unsigned long)__va(0x0UL);
save_pgd = *pgd_offset_k(0x0UL);
set_pgd(pgd_offset_k(0x0UL), *pgd_offset_k(vaddress));
__flush_tlb_all();
}
void __init efi_call_phys_epilog(void)
{
/*
* After the lock is released, the original page table is restored.
*/
set_pgd(pgd_offset_k(0x0UL), save_pgd);
__flush_tlb_all();
local_irq_restore(efi_flags);
early_runtime_code_mapping_set_exec(0);
}
void __iomem *__init efi_ioremap(unsigned long phys_addr, unsigned long size,
u32 type)
{
unsigned long last_map_pfn;
if (type == EFI_MEMORY_MAPPED_IO)
return ioremap(phys_addr, size);
last_map_pfn = init_memory_mapping(phys_addr, phys_addr + size);
if ((last_map_pfn << PAGE_SHIFT) < phys_addr + size)
return NULL;
return (void __iomem *)__va(phys_addr);
}