linux/arch/x86/kernel/head64.c
Linus Torvalds c47f39e3b7 Merge branch 'x86/microcode' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 microcode loading update from Peter Anvin:
 "This patchset lets us update the CPU microcode very, very early in
  initialization if the BIOS fails to do so (never happens, right?)

  This is handy for dealing with things like the Atom erratum where we
  have to run without PSE because microcode loading happens too late.

  As I mentioned in the x86/mm push request it depends on that
  infrastructure but it is otherwise a standalone feature."

* 'x86/microcode' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/Kconfig: Make early microcode loading a configuration feature
  x86/mm/init.c: Copy ucode from initrd image to kernel memory
  x86/head64.c: Early update ucode in 64-bit
  x86/head_32.S: Early update ucode in 32-bit
  x86/microcode_intel_early.c: Early update ucode on Intel's CPU
  x86/tlbflush.h: Define __native_flush_tlb_global_irq_disabled()
  x86/microcode_intel_lib.c: Early update ucode on Intel's CPU
  x86/microcode_core_early.c: Define interfaces for early loading ucode
  x86/common.c: load ucode in 64 bit or show loading ucode info in 32 bit on AP
  x86/common.c: Make have_cpuid_p() a global function
  x86/microcode_intel.h: Define functions and macros for early loading ucode
  x86, doc: Documentation for early microcode loading
2013-02-22 19:22:52 -08:00

194 lines
4.9 KiB
C

/*
* prepare to run common code
*
* Copyright (C) 2000 Andrea Arcangeli <andrea@suse.de> SuSE
*/
#include <linux/init.h>
#include <linux/linkage.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/percpu.h>
#include <linux/start_kernel.h>
#include <linux/io.h>
#include <linux/memblock.h>
#include <asm/processor.h>
#include <asm/proto.h>
#include <asm/smp.h>
#include <asm/setup.h>
#include <asm/desc.h>
#include <asm/pgtable.h>
#include <asm/tlbflush.h>
#include <asm/sections.h>
#include <asm/kdebug.h>
#include <asm/e820.h>
#include <asm/bios_ebda.h>
#include <asm/bootparam_utils.h>
#include <asm/microcode.h>
/*
* Manage page tables very early on.
*/
extern pgd_t early_level4_pgt[PTRS_PER_PGD];
extern pmd_t early_dynamic_pgts[EARLY_DYNAMIC_PAGE_TABLES][PTRS_PER_PMD];
static unsigned int __initdata next_early_pgt = 2;
/* Wipe all early page tables except for the kernel symbol map */
static void __init reset_early_page_tables(void)
{
unsigned long i;
for (i = 0; i < PTRS_PER_PGD-1; i++)
early_level4_pgt[i].pgd = 0;
next_early_pgt = 0;
write_cr3(__pa(early_level4_pgt));
}
/* Create a new PMD entry */
int __init early_make_pgtable(unsigned long address)
{
unsigned long physaddr = address - __PAGE_OFFSET;
unsigned long i;
pgdval_t pgd, *pgd_p;
pudval_t pud, *pud_p;
pmdval_t pmd, *pmd_p;
/* Invalid address or early pgt is done ? */
if (physaddr >= MAXMEM || read_cr3() != __pa(early_level4_pgt))
return -1;
again:
pgd_p = &early_level4_pgt[pgd_index(address)].pgd;
pgd = *pgd_p;
/*
* The use of __START_KERNEL_map rather than __PAGE_OFFSET here is
* critical -- __PAGE_OFFSET would point us back into the dynamic
* range and we might end up looping forever...
*/
if (pgd)
pud_p = (pudval_t *)((pgd & PTE_PFN_MASK) + __START_KERNEL_map - phys_base);
else {
if (next_early_pgt >= EARLY_DYNAMIC_PAGE_TABLES) {
reset_early_page_tables();
goto again;
}
pud_p = (pudval_t *)early_dynamic_pgts[next_early_pgt++];
for (i = 0; i < PTRS_PER_PUD; i++)
pud_p[i] = 0;
*pgd_p = (pgdval_t)pud_p - __START_KERNEL_map + phys_base + _KERNPG_TABLE;
}
pud_p += pud_index(address);
pud = *pud_p;
if (pud)
pmd_p = (pmdval_t *)((pud & PTE_PFN_MASK) + __START_KERNEL_map - phys_base);
else {
if (next_early_pgt >= EARLY_DYNAMIC_PAGE_TABLES) {
reset_early_page_tables();
goto again;
}
pmd_p = (pmdval_t *)early_dynamic_pgts[next_early_pgt++];
for (i = 0; i < PTRS_PER_PMD; i++)
pmd_p[i] = 0;
*pud_p = (pudval_t)pmd_p - __START_KERNEL_map + phys_base + _KERNPG_TABLE;
}
pmd = (physaddr & PMD_MASK) + (__PAGE_KERNEL_LARGE & ~_PAGE_GLOBAL);
pmd_p[pmd_index(address)] = pmd;
return 0;
}
/* Don't add a printk in there. printk relies on the PDA which is not initialized
yet. */
static void __init clear_bss(void)
{
memset(__bss_start, 0,
(unsigned long) __bss_stop - (unsigned long) __bss_start);
}
static unsigned long get_cmd_line_ptr(void)
{
unsigned long cmd_line_ptr = boot_params.hdr.cmd_line_ptr;
cmd_line_ptr |= (u64)boot_params.ext_cmd_line_ptr << 32;
return cmd_line_ptr;
}
static void __init copy_bootdata(char *real_mode_data)
{
char * command_line;
unsigned long cmd_line_ptr;
memcpy(&boot_params, real_mode_data, sizeof boot_params);
sanitize_boot_params(&boot_params);
cmd_line_ptr = get_cmd_line_ptr();
if (cmd_line_ptr) {
command_line = __va(cmd_line_ptr);
memcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
}
}
void __init x86_64_start_kernel(char * real_mode_data)
{
int i;
/*
* Build-time sanity checks on the kernel image and module
* area mappings. (these are purely build-time and produce no code)
*/
BUILD_BUG_ON(MODULES_VADDR < KERNEL_IMAGE_START);
BUILD_BUG_ON(MODULES_VADDR-KERNEL_IMAGE_START < KERNEL_IMAGE_SIZE);
BUILD_BUG_ON(MODULES_LEN + KERNEL_IMAGE_SIZE > 2*PUD_SIZE);
BUILD_BUG_ON((KERNEL_IMAGE_START & ~PMD_MASK) != 0);
BUILD_BUG_ON((MODULES_VADDR & ~PMD_MASK) != 0);
BUILD_BUG_ON(!(MODULES_VADDR > __START_KERNEL));
BUILD_BUG_ON(!(((MODULES_END - 1) & PGDIR_MASK) ==
(__START_KERNEL & PGDIR_MASK)));
BUILD_BUG_ON(__fix_to_virt(__end_of_fixed_addresses) <= MODULES_END);
/* Kill off the identity-map trampoline */
reset_early_page_tables();
/* clear bss before set_intr_gate with early_idt_handler */
clear_bss();
for (i = 0; i < NUM_EXCEPTION_VECTORS; i++)
set_intr_gate(i, &early_idt_handlers[i]);
load_idt((const struct desc_ptr *)&idt_descr);
copy_bootdata(__va(real_mode_data));
/*
* Load microcode early on BSP.
*/
load_ucode_bsp();
if (console_loglevel == 10)
early_printk("Kernel alive\n");
clear_page(init_level4_pgt);
/* set init_level4_pgt kernel high mapping*/
init_level4_pgt[511] = early_level4_pgt[511];
x86_64_start_reservations(real_mode_data);
}
void __init x86_64_start_reservations(char *real_mode_data)
{
/* version is always not zero if it is copied */
if (!boot_params.hdr.version)
copy_bootdata(__va(real_mode_data));
reserve_ebda_region();
start_kernel();
}