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| author | Michael Brown | 2014-08-26 13:29:54 +0200 |
|---|---|---|
| committer | Michael Brown | 2014-08-26 16:17:56 +0200 |
| commit | 3937274cfbde767ff07e839c5b45a21a0b248148 (patch) | |
| tree | 63618b96512063981aaf444354c29a363ce95de3 | |
| parent | [util] Use PCI length field to obtain length of individual images (diff) | |
| download | ipxe-3937274cfbde767ff07e839c5b45a21a0b248148.tar.gz ipxe-3937274cfbde767ff07e839c5b45a21a0b248148.tar.xz ipxe-3937274cfbde767ff07e839c5b45a21a0b248148.zip | |
[mromprefix] Use PCI length field to obtain length of individual images
mromprefix.S currently uses the initialisation length field (single
byte at offset 0x02) to determine the length of a ROM image within a
multi-image ROM BAR. For PCI ROM images with a code type other than
0, the initialisation length field may not be present.
Fix by using the PCI header's image length field instead.
Inspired-by: Swift Geek <swiftgeek@gmail.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
| -rw-r--r-- | src/arch/i386/prefix/mromprefix.S | 24 |
1 files changed, 17 insertions, 7 deletions
diff --git a/src/arch/i386/prefix/mromprefix.S b/src/arch/i386/prefix/mromprefix.S index 97ddd591e..43f0d97de 100644 --- a/src/arch/i386/prefix/mromprefix.S +++ b/src/arch/i386/prefix/mromprefix.S @@ -30,6 +30,8 @@ FILE_LICENCE ( GPL2_OR_LATER ) #define PCI_BAR_5 0x24 #define PCI_BAR_EXPROM 0x30 +#define PCIR_SIGNATURE ( 'P' + ( 'C' << 8 ) + ( 'I' << 16 ) + ( 'R' << 24 ) ) + #define ROMPREFIX_EXCLUDE_PAYLOAD 1 #define ROMPREFIX_MORE_IMAGES 1 #define _pcirom_start _mrom_start @@ -158,18 +160,26 @@ find_mem_bar: call pci_write_config_dword /* Locate our ROM image */ -1: movl $0xaa55, %ecx /* 55aa signature */ +1: movl $0xaa55, %ecx /* 55aa signature */ addr32 es cmpw %cx, (%eax) - je 2f - stc - movl %eax, %esi /* Report failure address */ - jmp 99f -2: addr32 es cmpl $_build_id, build_id(%eax) + jne 2f + movl $PCIR_SIGNATURE, %ecx /* PCIR signature */ + addr32 es movzwl 0x18(%eax), %edx + addr32 es cmpl %ecx, (%eax,%edx) + jne 2f + addr32 es cmpl $_build_id, build_id(%eax) /* iPXE build ID */ je 3f - addr32 es movzbl 2(%eax), %ecx + movl $0x80, %ecx /* Last image */ + addr32 es testb %cl, 0x15(%eax,%edx) + jnz 2f + addr32 es movzwl 0x10(%eax,%edx), %ecx /* PCIR image length */ shll $9, %ecx addl %ecx, %eax jmp 1b +2: /* Failure */ + stc + movl %eax, %esi /* Report failure address */ + jmp 99f 3: /* Copy payload to buffer, or set buffer address to BAR address */ |