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5a5a51db78
%cr4 is supposed to reflect a set of features into which the operating system is opting in. If the BIOS or bootloader leaks bits here, this is not desirable. Consider a bootloader passing in %cr4.pae set to a legacy paging kernel, for example -- it will not have any immediate effect, but the kernel would crash when turning paging on. A similar argument applies to %eflags, and since we have to look for %eflags.id being settable we can use a sequence which clears %eflags as a side effect. Note that we already do this for x86-64. Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/1348529239-17943-1-git-send-email-hpa@linux.intel.com
765 lines
18 KiB
ArmAsm
765 lines
18 KiB
ArmAsm
/*
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*
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* Copyright (C) 1991, 1992 Linus Torvalds
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*
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* Enhanced CPU detection and feature setting code by Mike Jagdis
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* and Martin Mares, November 1997.
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*/
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.text
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#include <linux/threads.h>
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#include <linux/init.h>
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#include <linux/linkage.h>
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#include <asm/segment.h>
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#include <asm/page_types.h>
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#include <asm/pgtable_types.h>
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#include <asm/cache.h>
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#include <asm/thread_info.h>
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#include <asm/asm-offsets.h>
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#include <asm/setup.h>
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#include <asm/processor-flags.h>
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#include <asm/msr-index.h>
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#include <asm/cpufeature.h>
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#include <asm/percpu.h>
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#include <asm/nops.h>
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/* Physical address */
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#define pa(X) ((X) - __PAGE_OFFSET)
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/*
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* References to members of the new_cpu_data structure.
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*/
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#define X86 new_cpu_data+CPUINFO_x86
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#define X86_VENDOR new_cpu_data+CPUINFO_x86_vendor
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#define X86_MODEL new_cpu_data+CPUINFO_x86_model
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#define X86_MASK new_cpu_data+CPUINFO_x86_mask
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#define X86_HARD_MATH new_cpu_data+CPUINFO_hard_math
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#define X86_CPUID new_cpu_data+CPUINFO_cpuid_level
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#define X86_CAPABILITY new_cpu_data+CPUINFO_x86_capability
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#define X86_VENDOR_ID new_cpu_data+CPUINFO_x86_vendor_id
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/*
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* This is how much memory in addition to the memory covered up to
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* and including _end we need mapped initially.
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* We need:
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* (KERNEL_IMAGE_SIZE/4096) / 1024 pages (worst case, non PAE)
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* (KERNEL_IMAGE_SIZE/4096) / 512 + 4 pages (worst case for PAE)
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*
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* Modulo rounding, each megabyte assigned here requires a kilobyte of
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* memory, which is currently unreclaimed.
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*
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* This should be a multiple of a page.
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*
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* KERNEL_IMAGE_SIZE should be greater than pa(_end)
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* and small than max_low_pfn, otherwise will waste some page table entries
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*/
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#if PTRS_PER_PMD > 1
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#define PAGE_TABLE_SIZE(pages) (((pages) / PTRS_PER_PMD) + PTRS_PER_PGD)
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#else
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#define PAGE_TABLE_SIZE(pages) ((pages) / PTRS_PER_PGD)
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#endif
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/* Number of possible pages in the lowmem region */
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LOWMEM_PAGES = (((1<<32) - __PAGE_OFFSET) >> PAGE_SHIFT)
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/* Enough space to fit pagetables for the low memory linear map */
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MAPPING_BEYOND_END = PAGE_TABLE_SIZE(LOWMEM_PAGES) << PAGE_SHIFT
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/*
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* Worst-case size of the kernel mapping we need to make:
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* a relocatable kernel can live anywhere in lowmem, so we need to be able
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* to map all of lowmem.
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*/
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KERNEL_PAGES = LOWMEM_PAGES
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INIT_MAP_SIZE = PAGE_TABLE_SIZE(KERNEL_PAGES) * PAGE_SIZE
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RESERVE_BRK(pagetables, INIT_MAP_SIZE)
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/*
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* 32-bit kernel entrypoint; only used by the boot CPU. On entry,
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* %esi points to the real-mode code as a 32-bit pointer.
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* CS and DS must be 4 GB flat segments, but we don't depend on
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* any particular GDT layout, because we load our own as soon as we
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* can.
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*/
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__HEAD
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ENTRY(startup_32)
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movl pa(stack_start),%ecx
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/* test KEEP_SEGMENTS flag to see if the bootloader is asking
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us to not reload segments */
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testb $(1<<6), BP_loadflags(%esi)
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jnz 2f
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/*
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* Set segments to known values.
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*/
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lgdt pa(boot_gdt_descr)
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movl $(__BOOT_DS),%eax
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movl %eax,%ds
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movl %eax,%es
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movl %eax,%fs
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movl %eax,%gs
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movl %eax,%ss
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2:
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leal -__PAGE_OFFSET(%ecx),%esp
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/*
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* Clear BSS first so that there are no surprises...
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*/
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cld
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xorl %eax,%eax
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movl $pa(__bss_start),%edi
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movl $pa(__bss_stop),%ecx
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subl %edi,%ecx
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shrl $2,%ecx
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rep ; stosl
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/*
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* Copy bootup parameters out of the way.
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* Note: %esi still has the pointer to the real-mode data.
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* With the kexec as boot loader, parameter segment might be loaded beyond
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* kernel image and might not even be addressable by early boot page tables.
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* (kexec on panic case). Hence copy out the parameters before initializing
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* page tables.
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*/
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movl $pa(boot_params),%edi
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movl $(PARAM_SIZE/4),%ecx
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cld
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rep
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movsl
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movl pa(boot_params) + NEW_CL_POINTER,%esi
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andl %esi,%esi
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jz 1f # No command line
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movl $pa(boot_command_line),%edi
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movl $(COMMAND_LINE_SIZE/4),%ecx
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rep
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movsl
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1:
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#ifdef CONFIG_OLPC
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/* save OFW's pgdir table for later use when calling into OFW */
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movl %cr3, %eax
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movl %eax, pa(olpc_ofw_pgd)
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#endif
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/*
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* Initialize page tables. This creates a PDE and a set of page
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* tables, which are located immediately beyond __brk_base. The variable
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* _brk_end is set up to point to the first "safe" location.
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* Mappings are created both at virtual address 0 (identity mapping)
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* and PAGE_OFFSET for up to _end.
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*/
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#ifdef CONFIG_X86_PAE
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/*
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* In PAE mode initial_page_table is statically defined to contain
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* enough entries to cover the VMSPLIT option (that is the top 1, 2 or 3
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* entries). The identity mapping is handled by pointing two PGD entries
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* to the first kernel PMD.
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*
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* Note the upper half of each PMD or PTE are always zero at this stage.
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*/
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#define KPMDS (((-__PAGE_OFFSET) >> 30) & 3) /* Number of kernel PMDs */
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xorl %ebx,%ebx /* %ebx is kept at zero */
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movl $pa(__brk_base), %edi
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movl $pa(initial_pg_pmd), %edx
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movl $PTE_IDENT_ATTR, %eax
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10:
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leal PDE_IDENT_ATTR(%edi),%ecx /* Create PMD entry */
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movl %ecx,(%edx) /* Store PMD entry */
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/* Upper half already zero */
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addl $8,%edx
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movl $512,%ecx
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11:
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stosl
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xchgl %eax,%ebx
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stosl
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xchgl %eax,%ebx
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addl $0x1000,%eax
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loop 11b
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/*
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* End condition: we must map up to the end + MAPPING_BEYOND_END.
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*/
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movl $pa(_end) + MAPPING_BEYOND_END + PTE_IDENT_ATTR, %ebp
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cmpl %ebp,%eax
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jb 10b
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1:
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addl $__PAGE_OFFSET, %edi
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movl %edi, pa(_brk_end)
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shrl $12, %eax
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movl %eax, pa(max_pfn_mapped)
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/* Do early initialization of the fixmap area */
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movl $pa(initial_pg_fixmap)+PDE_IDENT_ATTR,%eax
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movl %eax,pa(initial_pg_pmd+0x1000*KPMDS-8)
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#else /* Not PAE */
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page_pde_offset = (__PAGE_OFFSET >> 20);
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movl $pa(__brk_base), %edi
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movl $pa(initial_page_table), %edx
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movl $PTE_IDENT_ATTR, %eax
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10:
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leal PDE_IDENT_ATTR(%edi),%ecx /* Create PDE entry */
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movl %ecx,(%edx) /* Store identity PDE entry */
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movl %ecx,page_pde_offset(%edx) /* Store kernel PDE entry */
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addl $4,%edx
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movl $1024, %ecx
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11:
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stosl
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addl $0x1000,%eax
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loop 11b
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/*
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* End condition: we must map up to the end + MAPPING_BEYOND_END.
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*/
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movl $pa(_end) + MAPPING_BEYOND_END + PTE_IDENT_ATTR, %ebp
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cmpl %ebp,%eax
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jb 10b
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addl $__PAGE_OFFSET, %edi
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movl %edi, pa(_brk_end)
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shrl $12, %eax
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movl %eax, pa(max_pfn_mapped)
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/* Do early initialization of the fixmap area */
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movl $pa(initial_pg_fixmap)+PDE_IDENT_ATTR,%eax
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movl %eax,pa(initial_page_table+0xffc)
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#endif
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#ifdef CONFIG_PARAVIRT
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/* This is can only trip for a broken bootloader... */
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cmpw $0x207, pa(boot_params + BP_version)
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jb default_entry
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/* Paravirt-compatible boot parameters. Look to see what architecture
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we're booting under. */
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movl pa(boot_params + BP_hardware_subarch), %eax
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cmpl $num_subarch_entries, %eax
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jae bad_subarch
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movl pa(subarch_entries)(,%eax,4), %eax
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subl $__PAGE_OFFSET, %eax
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jmp *%eax
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bad_subarch:
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WEAK(lguest_entry)
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WEAK(xen_entry)
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/* Unknown implementation; there's really
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nothing we can do at this point. */
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ud2a
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__INITDATA
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subarch_entries:
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.long default_entry /* normal x86/PC */
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.long lguest_entry /* lguest hypervisor */
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.long xen_entry /* Xen hypervisor */
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.long default_entry /* Moorestown MID */
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num_subarch_entries = (. - subarch_entries) / 4
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.previous
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#else
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jmp default_entry
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#endif /* CONFIG_PARAVIRT */
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/*
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* Non-boot CPU entry point; entered from trampoline.S
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* We can't lgdt here, because lgdt itself uses a data segment, but
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* we know the trampoline has already loaded the boot_gdt for us.
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*
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* If cpu hotplug is not supported then this code can go in init section
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* which will be freed later
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*/
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__CPUINIT
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ENTRY(startup_32_smp)
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cld
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movl $(__BOOT_DS),%eax
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movl %eax,%ds
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movl %eax,%es
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movl %eax,%fs
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movl %eax,%gs
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movl pa(stack_start),%ecx
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movl %eax,%ss
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leal -__PAGE_OFFSET(%ecx),%esp
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default_entry:
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/*
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* New page tables may be in 4Mbyte page mode and may
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* be using the global pages.
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*
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* NOTE! If we are on a 486 we may have no cr4 at all!
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* Specifically, cr4 exists if and only if CPUID exists,
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* which in turn exists if and only if EFLAGS.ID exists.
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*/
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movl $X86_EFLAGS_ID,%ecx
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pushl %ecx
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popfl
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pushfl
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popl %eax
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pushl $0
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popfl
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pushfl
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popl %edx
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xorl %edx,%eax
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testl %ecx,%eax
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jz 6f # No ID flag = no CPUID = no CR4
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movl pa(mmu_cr4_features),%eax
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movl %eax,%cr4
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testb $X86_CR4_PAE, %al # check if PAE is enabled
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jz 6f
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/* Check if extended functions are implemented */
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movl $0x80000000, %eax
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cpuid
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/* Value must be in the range 0x80000001 to 0x8000ffff */
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subl $0x80000001, %eax
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cmpl $(0x8000ffff-0x80000001), %eax
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ja 6f
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/* Clear bogus XD_DISABLE bits */
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call verify_cpu
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mov $0x80000001, %eax
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cpuid
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/* Execute Disable bit supported? */
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btl $(X86_FEATURE_NX & 31), %edx
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jnc 6f
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/* Setup EFER (Extended Feature Enable Register) */
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movl $MSR_EFER, %ecx
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rdmsr
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btsl $_EFER_NX, %eax
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/* Make changes effective */
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wrmsr
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6:
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/*
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* Enable paging
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*/
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movl $pa(initial_page_table), %eax
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movl %eax,%cr3 /* set the page table pointer.. */
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movl %cr0,%eax
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orl $X86_CR0_PG,%eax
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movl %eax,%cr0 /* ..and set paging (PG) bit */
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ljmp $__BOOT_CS,$1f /* Clear prefetch and normalize %eip */
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1:
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/* Shift the stack pointer to a virtual address */
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addl $__PAGE_OFFSET, %esp
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/*
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* Initialize eflags. Some BIOS's leave bits like NT set. This would
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* confuse the debugger if this code is traced.
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* XXX - best to initialize before switching to protected mode.
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*/
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pushl $0
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popfl
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/*
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* start system 32-bit setup. We need to re-do some of the things done
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* in 16-bit mode for the "real" operations.
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*/
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movl setup_once_ref,%eax
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andl %eax,%eax
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jz 1f # Did we do this already?
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call *%eax
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1:
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/* check if it is 486 or 386. */
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/*
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* XXX - this does a lot of unnecessary setup. Alignment checks don't
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* apply at our cpl of 0 and the stack ought to be aligned already, and
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* we don't need to preserve eflags.
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*/
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movl $-1,X86_CPUID # -1 for no CPUID initially
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movb $3,X86 # at least 386
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pushfl # push EFLAGS
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popl %eax # get EFLAGS
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movl %eax,%ecx # save original EFLAGS
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xorl $0x240000,%eax # flip AC and ID bits in EFLAGS
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pushl %eax # copy to EFLAGS
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popfl # set EFLAGS
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pushfl # get new EFLAGS
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popl %eax # put it in eax
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xorl %ecx,%eax # change in flags
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pushl %ecx # restore original EFLAGS
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popfl
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testl $0x40000,%eax # check if AC bit changed
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je is386
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movb $4,X86 # at least 486
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testl $0x200000,%eax # check if ID bit changed
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je is486
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/* get vendor info */
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xorl %eax,%eax # call CPUID with 0 -> return vendor ID
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cpuid
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movl %eax,X86_CPUID # save CPUID level
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movl %ebx,X86_VENDOR_ID # lo 4 chars
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movl %edx,X86_VENDOR_ID+4 # next 4 chars
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movl %ecx,X86_VENDOR_ID+8 # last 4 chars
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orl %eax,%eax # do we have processor info as well?
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je is486
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movl $1,%eax # Use the CPUID instruction to get CPU type
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cpuid
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movb %al,%cl # save reg for future use
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andb $0x0f,%ah # mask processor family
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movb %ah,X86
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andb $0xf0,%al # mask model
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shrb $4,%al
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movb %al,X86_MODEL
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andb $0x0f,%cl # mask mask revision
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movb %cl,X86_MASK
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movl %edx,X86_CAPABILITY
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is486: movl $0x50022,%ecx # set AM, WP, NE and MP
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jmp 2f
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is386: movl $2,%ecx # set MP
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2: movl %cr0,%eax
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andl $0x80000011,%eax # Save PG,PE,ET
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orl %ecx,%eax
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movl %eax,%cr0
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call check_x87
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lgdt early_gdt_descr
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lidt idt_descr
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ljmp $(__KERNEL_CS),$1f
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1: movl $(__KERNEL_DS),%eax # reload all the segment registers
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movl %eax,%ss # after changing gdt.
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movl $(__USER_DS),%eax # DS/ES contains default USER segment
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movl %eax,%ds
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movl %eax,%es
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movl $(__KERNEL_PERCPU), %eax
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movl %eax,%fs # set this cpu's percpu
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movl $(__KERNEL_STACK_CANARY),%eax
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movl %eax,%gs
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xorl %eax,%eax # Clear LDT
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lldt %ax
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cld # gcc2 wants the direction flag cleared at all times
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pushl $0 # fake return address for unwinder
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jmp *(initial_code)
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/*
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* We depend on ET to be correct. This checks for 287/387.
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*/
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check_x87:
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movb $0,X86_HARD_MATH
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clts
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fninit
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fstsw %ax
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cmpb $0,%al
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je 1f
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movl %cr0,%eax /* no coprocessor: have to set bits */
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xorl $4,%eax /* set EM */
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movl %eax,%cr0
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ret
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ALIGN
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1: movb $1,X86_HARD_MATH
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.byte 0xDB,0xE4 /* fsetpm for 287, ignored by 387 */
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ret
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#include "verify_cpu.S"
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/*
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* setup_once
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*
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* The setup work we only want to run on the BSP.
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*
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* Warning: %esi is live across this function.
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*/
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__INIT
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setup_once:
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/*
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* Set up a idt with 256 entries pointing to ignore_int,
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* interrupt gates. It doesn't actually load idt - that needs
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* to be done on each CPU. Interrupts are enabled elsewhere,
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* when we can be relatively sure everything is ok.
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*/
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movl $idt_table,%edi
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movl $early_idt_handlers,%eax
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movl $NUM_EXCEPTION_VECTORS,%ecx
|
|
1:
|
|
movl %eax,(%edi)
|
|
movl %eax,4(%edi)
|
|
/* interrupt gate, dpl=0, present */
|
|
movl $(0x8E000000 + __KERNEL_CS),2(%edi)
|
|
addl $9,%eax
|
|
addl $8,%edi
|
|
loop 1b
|
|
|
|
movl $256 - NUM_EXCEPTION_VECTORS,%ecx
|
|
movl $ignore_int,%edx
|
|
movl $(__KERNEL_CS << 16),%eax
|
|
movw %dx,%ax /* selector = 0x0010 = cs */
|
|
movw $0x8E00,%dx /* interrupt gate - dpl=0, present */
|
|
2:
|
|
movl %eax,(%edi)
|
|
movl %edx,4(%edi)
|
|
addl $8,%edi
|
|
loop 2b
|
|
|
|
#ifdef CONFIG_CC_STACKPROTECTOR
|
|
/*
|
|
* Configure the stack canary. The linker can't handle this by
|
|
* relocation. Manually set base address in stack canary
|
|
* segment descriptor.
|
|
*/
|
|
movl $gdt_page,%eax
|
|
movl $stack_canary,%ecx
|
|
movw %cx, 8 * GDT_ENTRY_STACK_CANARY + 2(%eax)
|
|
shrl $16, %ecx
|
|
movb %cl, 8 * GDT_ENTRY_STACK_CANARY + 4(%eax)
|
|
movb %ch, 8 * GDT_ENTRY_STACK_CANARY + 7(%eax)
|
|
#endif
|
|
|
|
andl $0,setup_once_ref /* Once is enough, thanks */
|
|
ret
|
|
|
|
ENTRY(early_idt_handlers)
|
|
# 36(%esp) %eflags
|
|
# 32(%esp) %cs
|
|
# 28(%esp) %eip
|
|
# 24(%rsp) error code
|
|
i = 0
|
|
.rept NUM_EXCEPTION_VECTORS
|
|
.if (EXCEPTION_ERRCODE_MASK >> i) & 1
|
|
ASM_NOP2
|
|
.else
|
|
pushl $0 # Dummy error code, to make stack frame uniform
|
|
.endif
|
|
pushl $i # 20(%esp) Vector number
|
|
jmp early_idt_handler
|
|
i = i + 1
|
|
.endr
|
|
ENDPROC(early_idt_handlers)
|
|
|
|
/* This is global to keep gas from relaxing the jumps */
|
|
ENTRY(early_idt_handler)
|
|
cld
|
|
cmpl $2,%ss:early_recursion_flag
|
|
je hlt_loop
|
|
incl %ss:early_recursion_flag
|
|
|
|
push %eax # 16(%esp)
|
|
push %ecx # 12(%esp)
|
|
push %edx # 8(%esp)
|
|
push %ds # 4(%esp)
|
|
push %es # 0(%esp)
|
|
movl $(__KERNEL_DS),%eax
|
|
movl %eax,%ds
|
|
movl %eax,%es
|
|
|
|
cmpl $(__KERNEL_CS),32(%esp)
|
|
jne 10f
|
|
|
|
leal 28(%esp),%eax # Pointer to %eip
|
|
call early_fixup_exception
|
|
andl %eax,%eax
|
|
jnz ex_entry /* found an exception entry */
|
|
|
|
10:
|
|
#ifdef CONFIG_PRINTK
|
|
xorl %eax,%eax
|
|
movw %ax,2(%esp) /* clean up the segment values on some cpus */
|
|
movw %ax,6(%esp)
|
|
movw %ax,34(%esp)
|
|
leal 40(%esp),%eax
|
|
pushl %eax /* %esp before the exception */
|
|
pushl %ebx
|
|
pushl %ebp
|
|
pushl %esi
|
|
pushl %edi
|
|
movl %cr2,%eax
|
|
pushl %eax
|
|
pushl (20+6*4)(%esp) /* trapno */
|
|
pushl $fault_msg
|
|
call printk
|
|
#endif
|
|
call dump_stack
|
|
hlt_loop:
|
|
hlt
|
|
jmp hlt_loop
|
|
|
|
ex_entry:
|
|
pop %es
|
|
pop %ds
|
|
pop %edx
|
|
pop %ecx
|
|
pop %eax
|
|
addl $8,%esp /* drop vector number and error code */
|
|
decl %ss:early_recursion_flag
|
|
iret
|
|
ENDPROC(early_idt_handler)
|
|
|
|
/* This is the default interrupt "handler" :-) */
|
|
ALIGN
|
|
ignore_int:
|
|
cld
|
|
#ifdef CONFIG_PRINTK
|
|
pushl %eax
|
|
pushl %ecx
|
|
pushl %edx
|
|
pushl %es
|
|
pushl %ds
|
|
movl $(__KERNEL_DS),%eax
|
|
movl %eax,%ds
|
|
movl %eax,%es
|
|
cmpl $2,early_recursion_flag
|
|
je hlt_loop
|
|
incl early_recursion_flag
|
|
pushl 16(%esp)
|
|
pushl 24(%esp)
|
|
pushl 32(%esp)
|
|
pushl 40(%esp)
|
|
pushl $int_msg
|
|
call printk
|
|
|
|
call dump_stack
|
|
|
|
addl $(5*4),%esp
|
|
popl %ds
|
|
popl %es
|
|
popl %edx
|
|
popl %ecx
|
|
popl %eax
|
|
#endif
|
|
iret
|
|
ENDPROC(ignore_int)
|
|
__INITDATA
|
|
.align 4
|
|
early_recursion_flag:
|
|
.long 0
|
|
|
|
__REFDATA
|
|
.align 4
|
|
ENTRY(initial_code)
|
|
.long i386_start_kernel
|
|
ENTRY(setup_once_ref)
|
|
.long setup_once
|
|
|
|
/*
|
|
* BSS section
|
|
*/
|
|
__PAGE_ALIGNED_BSS
|
|
.align PAGE_SIZE
|
|
#ifdef CONFIG_X86_PAE
|
|
initial_pg_pmd:
|
|
.fill 1024*KPMDS,4,0
|
|
#else
|
|
ENTRY(initial_page_table)
|
|
.fill 1024,4,0
|
|
#endif
|
|
initial_pg_fixmap:
|
|
.fill 1024,4,0
|
|
ENTRY(empty_zero_page)
|
|
.fill 4096,1,0
|
|
ENTRY(swapper_pg_dir)
|
|
.fill 1024,4,0
|
|
|
|
/*
|
|
* This starts the data section.
|
|
*/
|
|
#ifdef CONFIG_X86_PAE
|
|
__PAGE_ALIGNED_DATA
|
|
/* Page-aligned for the benefit of paravirt? */
|
|
.align PAGE_SIZE
|
|
ENTRY(initial_page_table)
|
|
.long pa(initial_pg_pmd+PGD_IDENT_ATTR),0 /* low identity map */
|
|
# if KPMDS == 3
|
|
.long pa(initial_pg_pmd+PGD_IDENT_ATTR),0
|
|
.long pa(initial_pg_pmd+PGD_IDENT_ATTR+0x1000),0
|
|
.long pa(initial_pg_pmd+PGD_IDENT_ATTR+0x2000),0
|
|
# elif KPMDS == 2
|
|
.long 0,0
|
|
.long pa(initial_pg_pmd+PGD_IDENT_ATTR),0
|
|
.long pa(initial_pg_pmd+PGD_IDENT_ATTR+0x1000),0
|
|
# elif KPMDS == 1
|
|
.long 0,0
|
|
.long 0,0
|
|
.long pa(initial_pg_pmd+PGD_IDENT_ATTR),0
|
|
# else
|
|
# error "Kernel PMDs should be 1, 2 or 3"
|
|
# endif
|
|
.align PAGE_SIZE /* needs to be page-sized too */
|
|
#endif
|
|
|
|
.data
|
|
.balign 4
|
|
ENTRY(stack_start)
|
|
.long init_thread_union+THREAD_SIZE
|
|
|
|
__INITRODATA
|
|
int_msg:
|
|
.asciz "Unknown interrupt or fault at: %p %p %p\n"
|
|
|
|
fault_msg:
|
|
/* fault info: */
|
|
.ascii "BUG: Int %d: CR2 %p\n"
|
|
/* regs pushed in early_idt_handler: */
|
|
.ascii " EDI %p ESI %p EBP %p EBX %p\n"
|
|
.ascii " ESP %p ES %p DS %p\n"
|
|
.ascii " EDX %p ECX %p EAX %p\n"
|
|
/* fault frame: */
|
|
.ascii " vec %p err %p EIP %p CS %p flg %p\n"
|
|
.ascii "Stack: %p %p %p %p %p %p %p %p\n"
|
|
.ascii " %p %p %p %p %p %p %p %p\n"
|
|
.asciz " %p %p %p %p %p %p %p %p\n"
|
|
|
|
#include "../../x86/xen/xen-head.S"
|
|
|
|
/*
|
|
* The IDT and GDT 'descriptors' are a strange 48-bit object
|
|
* only used by the lidt and lgdt instructions. They are not
|
|
* like usual segment descriptors - they consist of a 16-bit
|
|
* segment size, and 32-bit linear address value:
|
|
*/
|
|
|
|
.data
|
|
.globl boot_gdt_descr
|
|
.globl idt_descr
|
|
|
|
ALIGN
|
|
# early boot GDT descriptor (must use 1:1 address mapping)
|
|
.word 0 # 32 bit align gdt_desc.address
|
|
boot_gdt_descr:
|
|
.word __BOOT_DS+7
|
|
.long boot_gdt - __PAGE_OFFSET
|
|
|
|
.word 0 # 32-bit align idt_desc.address
|
|
idt_descr:
|
|
.word IDT_ENTRIES*8-1 # idt contains 256 entries
|
|
.long idt_table
|
|
|
|
# boot GDT descriptor (later on used by CPU#0):
|
|
.word 0 # 32 bit align gdt_desc.address
|
|
ENTRY(early_gdt_descr)
|
|
.word GDT_ENTRIES*8-1
|
|
.long gdt_page /* Overwritten for secondary CPUs */
|
|
|
|
/*
|
|
* The boot_gdt must mirror the equivalent in setup.S and is
|
|
* used only for booting.
|
|
*/
|
|
.align L1_CACHE_BYTES
|
|
ENTRY(boot_gdt)
|
|
.fill GDT_ENTRY_BOOT_CS,8,0
|
|
.quad 0x00cf9a000000ffff /* kernel 4GB code at 0x00000000 */
|
|
.quad 0x00cf92000000ffff /* kernel 4GB data at 0x00000000 */
|