diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/arch/i386/prefix/romprefix.S | 26 |
1 files changed, 20 insertions, 6 deletions
diff --git a/src/arch/i386/prefix/romprefix.S b/src/arch/i386/prefix/romprefix.S index dd602ddb7..49fd24b9a 100644 --- a/src/arch/i386/prefix/romprefix.S +++ b/src/arch/i386/prefix/romprefix.S @@ -13,6 +13,7 @@ FILE_LICENCE ( GPL2_OR_LATER ) #define PNP_SIGNATURE ( '$' + ( 'P' << 8 ) + ( 'n' << 16 ) + ( 'P' << 24 ) ) #define PMM_SIGNATURE ( '$' + ( 'P' << 8 ) + ( 'M' << 16 ) + ( 'M' << 24 ) ) #define PCI_SIGNATURE ( 'P' + ( 'C' << 8 ) + ( 'I' << 16 ) + ( ' ' << 24 ) ) +#define IBM_SIGNATURE ( ( 'I' << 24 ) + ( 'B' << 16 ) + ( 'M' << 8 ) + ' ' ) #define STACK_MAGIC ( 'L' + ( 'R' << 8 ) + ( 'E' << 16 ) + ( 'T' << 24 ) ) #define PMM_ALLOCATE 0x0000 #define PMM_FIND 0x0001 @@ -172,6 +173,7 @@ undiheader: init: /* Preserve registers, clear direction flag, set %ds=%cs */ pushaw + pushl %ebx pushw %ds pushw %es pushw %fs @@ -180,15 +182,14 @@ init: pushw %cs popw %ds - /* Shuffle some registers around. We need %di available for - * the print_xxx functions, and in a register that's - * addressable from %es, so shuffle as follows: + /* Shuffle some registers around. We need to use %di for the + * print_xxx functions, so shuffle as follows: * - * %di (pointer to PnP structure) => %bx * %bx (runtime segment address, for PCI 3.0) => %gs + * %edi (IBM signature) => %ebx */ movw %bx, %gs - movw %di, %bx + movl %edi, %ebx /* Store PCI bus:dev.fn address */ movw %ax, init_pci_busdevfn @@ -263,7 +264,16 @@ no_pci3: popl %edx popl %ebx - /* Check for PnP BIOS. Although %es:di should point to the + /* Check for IBM BIOS, which uses the PnP entry points but + * doesn't indicate PnP support. + */ + cmpl $IBM_SIGNATURE, %ebx + jne no_ibm + movw $init_message_ibm, %si + xorw %di, %di + call print_message + jmp pnp_done +no_ibm: /* Check for PnP BIOS. Although %es:di should point to the * PnP BIOS signature on entry, some BIOSes fail to do this. */ movw $( 0xf000 - 1 ), %bx @@ -416,6 +426,7 @@ no_pmm: popw %fs popw %es popw %ds + popl %ebx popaw /* Indicate boot capability to PnP BIOS, if present */ @@ -530,6 +541,9 @@ init_message: init_message_pci: .asciz " PCI" .size init_message_pci, . - init_message_pci +init_message_ibm: + .asciz " IBM" + .size init_message_ibm, . - init_message_ibm init_message_pnp: .asciz " PnP" .size init_message_pnp, . - init_message_pnp |