tell people that the segment descriptors are different for ROMCC and

GCC code.

git-svn-id: svn://svn.coreboot.org/coreboot/trunk@1740 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1

diff --git a/src/arch/i386/lib/c_start.S b/src/arch/i386/lib/c_start.S
index 2e397f884733e538b075296b1441b555c23f9cce..ccd0127dae1b5562ac1f3a8f4f4ae84b08fd3844 100644 (file)
--- a/src/arch/i386/lib/c_start.S
+++ b/src/arch/i386/lib/c_start.S
@@ -216,7 +216,7 @@ int_hand:
        popl    %ecx
        popl    %edx
        popl    %ebx
-       popl    %ebp /* Ignore saved %esp value */
+       popl    %ebp    /* Ignore saved %esp value */
        popl    %ebp
        popl    %esi
        popl    %edi
@@ -241,49 +241,50 @@ gdb_stub_breakpoint:
 
        .globl gdt, gdt_end, gdt_limit, idtarg
 
-gdt_limit = gdt_end - gdt - 1 /* compute the table limit */
+gdt_limit = gdt_end - gdt - 1  /* compute the table limit */
 gdtaddr:
        .word   gdt_limit
-       .long   gdt                /* we know the offset */
+       .long   gdt             /* we know the offset */
 
         .data
+
+       /* This is the gdt for GCC part of LinuxBIOS.
+        * It is different from the gdt in ROMCC/ASM part of LinuxBIOS
+        * which is defined in entry32.inc */
 gdt:
-// selgdt 0
+       /* selgdt 0, unused */
        .word   0x0000, 0x0000          /* dummy */
        .byte   0x00, 0x00, 0x00, 0x00
 
-// selgdt 8
+       /* selgdt 8, unused */
        .word   0x0000, 0x0000          /* dummy */
        .byte   0x00, 0x00, 0x00, 0x00
 
-// selgdt 0x10 
-/* flat code segment */
+       /* selgdt 0x10, flat code segment */
        .word   0xffff, 0x0000          
        .byte   0x00, 0x9b, 0xcf, 0x00  
-       
-//selgdt 0x18
-/* flat data segment */
+
+       /* selgdt 0x18, flat data segment */
        .word   0xffff, 0x0000          
        .byte   0x00, 0x93, 0xcf, 0x00  
 
-//selgdt 0x20
+       /* selgdt 0x20, unused */
        .word   0x0000, 0x0000          /* dummy */
        .byte   0x00, 0x00, 0x00, 0x00
 
 #if defined(CONFIG_LEGACY_VGABIOS) && (CONFIG_LEGACY_VGABIOS == 1)
-       // from monty:
-       /* 0x00009a00,0000ffffULL,   20h: 16-bit 64k code at 0x00000000 */
-        /* 0x00009200,0000ffffULL    28h: 16-bit 64k data at 0x00000000 */
-// selgdt 0x28
-/*16-bit 64k code at 0x00000000 */
+       /* from monty:
+        * 0x00009a00,0000ffffULL,   20h: 16-bit 64k code at 0x00000000
+         * 0x00009200,0000ffffULL    28h: 16-bit 64k data at 0x00000000 */
+
+       /* selgdt 0x28, 16-bit 64k code at 0x00000000 */
        .word 0xffff, 0x0000
-       .byte 0, 0x9a, 0, 0
+       .byte 0x00, 0x9a, 0x00, 0x00
 
-// selgdt 0x30
-/*16-bit 64k data at 0x00000000 */
+       /* selgdt 0x30, 16-bit 64k data at 0x00000000 */
        .word 0xffff, 0x0000
        .byte 0, 0x92, 0, 0
-#endif // defined(CONFIG_VGABIOS) && (CONFIG_VGABIOS == 1)
+#endif /* defined(CONFIG_VGABIOS) && (CONFIG_VGABIOS == 1) */
 gdt_end:
 
 idtarg:

diff --git a/src/cpu/x86/16bit/entry16.inc b/src/cpu/x86/16bit/entry16.inc
index 61726d8ad99c342fdac06d423fa750245799f2f1..674315fbd27bb513b90ab28cc139470be593be18 100644 (file)
--- a/src/cpu/x86/16bit/entry16.inc
+++ b/src/cpu/x86/16bit/entry16.inc
@@ -108,10 +108,10 @@ _start:
        /* Now that we are in protected mode jump to a 32 bit code segment. */
        data32  ljmp    $ROM_CODE_SEG, $__protected_start
 
-/** The gdt has a 4 Gb code segment at 0x10, and a 4 GB data segment
- * at 0x18; these are Linux-compatible. 
- */
-
+       /**
+        * The gdt is defined in entry32.inc, it has a 4 Gb code segment
+        * at 0x08, and a 4 GB data segment at 0x10;
+        */
 .align 4
 .globl gdtptr16
 gdtptr16:

diff --git a/src/cpu/x86/32bit/entry32.inc b/src/cpu/x86/32bit/entry32.inc
index 3d30a3f85f2795d1a5ae0f03de689025af0f5ea4..724aed32eb22125d2b61725d3e6294cf7e72d2b3 100644 (file)
--- a/src/cpu/x86/32bit/entry32.inc
+++ b/src/cpu/x86/32bit/entry32.inc
@@ -8,17 +8,20 @@
        .align  4
 .globl gdtptr
 
+       /* This is the gdt for ROMCC/ASM part of LinuxBIOS.
+        * It is different from the gdt in GCC part of LinuxBIOS
+        * which is defined in c_start.S */
 gdt:
 gdtptr:
        .word   gdt_end - gdt -1 /* compute the table limit */
        .long   gdt              /* we know the offset */
        .word   0
 
-/* flat code segment */
+       /* selgdt 0x08, flat code segment */
        .word   0xffff, 0x0000          
        .byte   0x00, 0x9b, 0xcf, 0x00  
-       
-/* flat data segment */
+
+       /* selgdt 0x10,flat data segment */
        .word   0xffff, 0x0000          
        .byte   0x00, 0x93, 0xcf, 0x00  
 

diff --git a/src/cpu/x86/lapic/secondary.S b/src/cpu/x86/lapic/secondary.S
index 5185021c3ca75cc441a879226daa5dfcf7c74fcc..b212f43b382b01e1f421e7c7233a7f09249b7af8 100644 (file)
--- a/src/cpu/x86/lapic/secondary.S
+++ b/src/cpu/x86/lapic/secondary.S
@@ -26,7 +26,7 @@ _secondary_start:
        orl     $0x60000001, %eax /* CD, NW, PE = 1 */
        movl    %eax, %cr0
 
-       ljmpl $0x10, $1f
+       ljmpl   $0x10, $1f
 1:     
        .code32
        movw    $0x18, %ax