x86, realmode: Move reboot_32.S to unified realmode code

Migrated reboot_32.S from x86_trampoline to the real-mode
blob.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com>
Link: http://lkml.kernel.org/r/1336501366-28617-5-git-send-email-jarkko.sakkinen@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

diff --git a/arch/x86/include/asm/realmode.h b/arch/x86/include/asm/realmode.h
index dc1bba534c142e9b478fd86c10205520be8ce7d0..bf26b06819314ccb69850d55b1e95703a08b5501 100644 (file)
--- a/arch/x86/include/asm/realmode.h
+++ b/arch/x86/include/asm/realmode.h
@@ -9,6 +9,10 @@ struct real_mode_header {
        u32     text_start;
        u32     ro_end;
        u32     end;
+       /* reboot */
+#ifdef CONFIG_X86_32
+       u32     machine_real_restart_asm;
+#endif
 } __attribute__((__packed__));
 
 extern struct real_mode_header real_mode_header;

diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index f9e19d4eb984d07b8659b6d26b9a6cbed4658199..b71ef35c7d77e866313fe4b03667dc5360a99bf7 100644 (file)
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -49,7 +49,6 @@ obj-$(CONFIG_STACKTRACE)      += stacktrace.o
 obj-y                          += cpu/
 obj-y                          += acpi/
 obj-y                          += reboot.o
-obj-$(CONFIG_X86_32)           += reboot_32.o
 obj-$(CONFIG_MCA)              += mca_32.o
 obj-$(CONFIG_X86_MSR)          += msr.o
 obj-$(CONFIG_X86_CPUID)                += cpuid.o

diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
index d840e69a853c0ed3fb48d1bd9f6abc2367275efa..050eff29a4bb938bd9374503b026d8411ca59e04 100644 (file)
--- a/arch/x86/kernel/reboot.c
+++ b/arch/x86/kernel/reboot.c
@@ -24,6 +24,7 @@
 #ifdef CONFIG_X86_32
 # include <linux/ctype.h>
 # include <linux/mc146818rtc.h>
+# include <asm/realmode.h>
 #else
 # include <asm/x86_init.h>
 #endif
@@ -332,15 +333,10 @@ static int __init reboot_init(void)
 }
 core_initcall(reboot_init);
 
-extern const unsigned char machine_real_restart_asm[];
-extern const u64 machine_real_restart_gdt[3];
-
 void machine_real_restart(unsigned int type)
 {
-       void *restart_va;
-       unsigned long restart_pa;
-       void (*restart_lowmem)(unsigned int);
-       u64 *lowmem_gdt;
+       void (*restart_lowmem)(unsigned int) = (void (*)(unsigned int))
+               real_mode_header.machine_real_restart_asm;
 
        local_irq_disable();
 
@@ -369,21 +365,6 @@ void machine_real_restart(unsigned int type)
           too. */
        *((unsigned short *)0x472) = reboot_mode;
 
-       /* Patch the GDT in the low memory trampoline */
-       lowmem_gdt = TRAMPOLINE_SYM(machine_real_restart_gdt);
-
-       restart_va = TRAMPOLINE_SYM(machine_real_restart_asm);
-       restart_pa = virt_to_phys(restart_va);
-       restart_lowmem = (void (*)(unsigned int))restart_pa;
-
-       /* GDT[0]: GDT self-pointer */
-       lowmem_gdt[0] =
-               (u64)(sizeof(machine_real_restart_gdt) - 1) +
-               ((u64)virt_to_phys(lowmem_gdt) << 16);
-       /* GDT[1]: 64K real mode code segment */
-       lowmem_gdt[1] =
-               GDT_ENTRY(0x009b, restart_pa, 0xffff);
-
        /* Jump to the identity-mapped low memory code */
        restart_lowmem(type);
 }

diff --git a/arch/x86/realmode/rm/Makefile b/arch/x86/realmode/rm/Makefile
index 7c3f202cbccf7a3ca8e037a87e5b5800732ec85e..3f851c488593382b0ec59ddad3b798cff8abddae 100644 (file)
--- a/arch/x86/realmode/rm/Makefile
+++ b/arch/x86/realmode/rm/Makefile
@@ -12,6 +12,7 @@ subdir- := wakeup
 always := realmode.bin
 
 realmode-y                     += header.o
+realmode-$(CONFIG_X86_32)      += reboot_32.o
 
 targets        += $(realmode-y)
 

diff --git a/arch/x86/realmode/rm/header.S b/arch/x86/realmode/rm/header.S
index 7be17f2c65a391dc2bba4d1f9c32fbe5681c0624..db21401c0c57325454796604bb73176ffff6797f 100644 (file)
--- a/arch/x86/realmode/rm/header.S
+++ b/arch/x86/realmode/rm/header.S
@@ -13,4 +13,7 @@ ENTRY(real_mode_header)
                .long   pa_text_start
                .long   pa_ro_end
                .long   pa_end
+#ifdef CONFIG_X86_32
+               .long   pa_machine_real_restart_asm
+#endif
 END(real_mode_header)

diff --git a/arch/x86/kernel/reboot_32.S b/arch/x86/realmode/rm/reboot_32.S
similarity index 73%
rename from arch/x86/kernel/reboot_32.S
rename to arch/x86/realmode/rm/reboot_32.S
index 1d5c46df0d787abc497a1d025a9a8fd2cd347026..83803c222b4ab66305918973a3c533c183f4baf4 100644 (file)
--- a/arch/x86/kernel/reboot_32.S
+++ b/arch/x86/realmode/rm/reboot_32.S
@@ -13,34 +13,21 @@
  *
  * This code is called with the restart type (0 = BIOS, 1 = APM) in %eax.
  */
-       .section ".x86_trampoline","a"
-       .balign 16
+       .section ".text32", "ax"
        .code32
-ENTRY(machine_real_restart_asm)
-r_base = .
-       /* Get our own relocated address */
-       call    1f
-1:     popl    %ebx
-       subl    $(1b - r_base), %ebx
-
-       /* Compute the equivalent real-mode segment */
-       movl    %ebx, %ecx
-       shrl    $4, %ecx
-       
-       /* Patch post-real-mode segment jump */
-       movw    (dispatch_table - r_base)(%ebx,%eax,2),%ax
-       movw    %ax, (101f - r_base)(%ebx)
-       movw    %cx, (102f - r_base)(%ebx)
+       .globl machine_real_restart_asm
 
+       .balign 16
+machine_real_restart_asm:
        /* Set up the IDT for real mode. */
-       lidtl   (machine_real_restart_idt - r_base)(%ebx)
+       lidtl   pa_machine_real_restart_idt
 
        /*
         * Set up a GDT from which we can load segment descriptors for real
         * mode.  The GDT is not used in real mode; it is just needed here to
         * prepare the descriptors.
         */
-       lgdtl   (machine_real_restart_gdt - r_base)(%ebx)
+       lgdtl   pa_machine_real_restart_gdt
 
        /*
         * Load the data segment registers with 16-bit compatible values
@@ -51,7 +38,7 @@ r_base = .
        movl    %ecx, %fs
        movl    %ecx, %gs
        movl    %ecx, %ss
-       ljmpl   $8, $1f - r_base
+       ljmpw   $8, $1f
 
 /*
  * This is 16-bit protected mode code to disable paging and the cache,
@@ -76,27 +63,32 @@ r_base = .
  *
  * Most of this work is probably excessive, but it is what is tested.
  */
+       .text
        .code16
+
+       .balign 16
+machine_real_restart_asm16:
 1:
        xorl    %ecx, %ecx
-       movl    %cr0, %eax
-       andl    $0x00000011, %eax
-       orl     $0x60000000, %eax
-       movl    %eax, %cr0
+       movl    %cr0, %edx
+       andl    $0x00000011, %edx
+       orl     $0x60000000, %edx
+       movl    %edx, %cr0
        movl    %ecx, %cr3
        movl    %cr0, %edx
        andl    $0x60000000, %edx       /* If no cache bits -> no wbinvd */
        jz      2f
        wbinvd
 2:
-       andb    $0x10, %al
-       movl    %eax, %cr0
+       andb    $0x10, %dl
+       movl    %edx, %cr0
        .byte   0xea                    /* ljmpw */
-101:   .word   0                       /* Offset */
-102:   .word   0                       /* Segment */
+       .word   3f                      /* Offset */
+       .word   real_mode_seg           /* Segment */
 
-bios:
-       ljmpw   $0xf000, $0xfff0
+3:
+       testb   $0, %al
+       jz      bios
 
 apm:
        movw    $0x1000, %ax
@@ -106,30 +98,37 @@ apm:
        movw    $0x0001, %bx
        movw    $0x0003, %cx
        int     $0x15
+       /* This should never return... */
 
-END(machine_real_restart_asm)
+bios:
+       ljmpw   $0xf000, $0xfff0
 
-       .balign 16
-       /* These must match <asm/reboot.h */
-dispatch_table:
-       .word   bios - r_base
-       .word   apm - r_base
-END(dispatch_table)
+       .section ".rodata", "a"
+       .globl  machine_real_restart_idt, machine_real_restart_gdt
 
        .balign 16
 machine_real_restart_idt:
        .word   0xffff          /* Length - real mode default value */
        .long   0               /* Base - real mode default value */
-END(machine_real_restart_idt)
 
        .balign 16
-ENTRY(machine_real_restart_gdt)
-       .quad   0               /* Self-pointer, filled in by PM code */
-       .quad   0               /* 16-bit code segment, filled in by PM code */
+machine_real_restart_gdt:
+       /* Self-pointer */
+       .word   0xffff          /* Length - real mode default value */
+       .long   pa_machine_real_restart_gdt
+       .word   0
+
+       /*
+        * 16-bit code segment pointing to real_mode_seg
+        * Selector value 8
+        */
+       .word   0xffff          /* Limit */
+       .long   0x9b000000 + pa_real_mode_base
+       .word   0
+
        /*
         * 16-bit data segment with the selector value 16 = 0x10 and
         * base value 0x100; since this is consistent with real mode
         * semantics we don't have to reload the segments once CR0.PE = 0.
         */
        .quad   GDT_ENTRY(0x0093, 0x100, 0xffff)
-END(machine_real_restart_gdt)