[PATCH 1/1] x86: all firmware tables must be paragraph aligned
On qemu-x86_64_defconfig the following was observed:
=> efidebug tables 00000000000f0074 eb9d2d31-2d88-11d3-9a16-0090273fc14d SMBIOS table
The SMBIOS configuration table does not point to a paragraph aligned address. The reason is that in write_tables() rom_addr is not aligned and copied to gd->arch.smbios_start.
The Simple Firmware Interface requires that the SFI table is paragraph aligned but our code does not guarantee this.
As all tables written in write_tables() must be paragraph aligned, we should implement the address rounding in write_tables() and not in table specific routines like copy_pirq_routing_table().
Add paragraph alignment in write_tables().
Signed-off-by: Heinrich Schuchardt heinrich.schuchardt@canonical.com --- arch/x86/lib/tables.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/arch/x86/lib/tables.c b/arch/x86/lib/tables.c index 5b5070f7ca..89d4d30a6a 100644 --- a/arch/x86/lib/tables.c +++ b/arch/x86/lib/tables.c @@ -97,6 +97,8 @@ int write_tables(void) int size = table->size ? : CONFIG_ROM_TABLE_SIZE; u32 rom_table_end;
+ rom_addr = ALIGN(rom_addr, 16); + if (!strcmp("smbios", table->name)) gd->arch.smbios_start = rom_addr;
On Mon, Jan 1, 2024 at 4:52 AM Heinrich Schuchardt heinrich.schuchardt@canonical.com wrote:
On qemu-x86_64_defconfig the following was observed:
=> efidebug tables 00000000000f0074 eb9d2d31-2d88-11d3-9a16-0090273fc14d SMBIOS tableThe SMBIOS configuration table does not point to a paragraph aligned address. The reason is that in write_tables() rom_addr is not aligned and copied to gd->arch.smbios_start.
The Simple Firmware Interface requires that the SFI table is paragraph aligned but our code does not guarantee this.
As all tables written in write_tables() must be paragraph aligned, we
paragraph-aligned
But was is a paragraph? Is that an x86 term?
should implement the address rounding in write_tables() and not in table specific routines like copy_pirq_routing_table().
Add paragraph alignment in write_tables().
Signed-off-by: Heinrich Schuchardt heinrich.schuchardt@canonical.com
arch/x86/lib/tables.c | 2 ++ 1 file changed, 2 insertions(+)
Reviewed-by: Simon Glass sjg@chromium.org
diff --git a/arch/x86/lib/tables.c b/arch/x86/lib/tables.c index 5b5070f7ca..89d4d30a6a 100644 --- a/arch/x86/lib/tables.c +++ b/arch/x86/lib/tables.c @@ -97,6 +97,8 @@ int write_tables(void) int size = table->size ? : CONFIG_ROM_TABLE_SIZE; u32 rom_table_end;
rom_addr = ALIGN(rom_addr, 16);if (!strcmp("smbios", table->name)) gd->arch.smbios_start = rom_addr;-- 2.43.0
On 1/1/24 23:41, Simon Glass wrote:
On Mon, Jan 1, 2024 at 4:52 AM Heinrich Schuchardt heinrich.schuchardt@canonical.com wrote:
On qemu-x86_64_defconfig the following was observed:
=> efidebug tables 00000000000f0074 eb9d2d31-2d88-11d3-9a16-0090273fc14d SMBIOS tableThe SMBIOS configuration table does not point to a paragraph aligned address. The reason is that in write_tables() rom_addr is not aligned and copied to gd->arch.smbios_start.
The Simple Firmware Interface requires that the SFI table is paragraph aligned but our code does not guarantee this.
As all tables written in write_tables() must be paragraph aligned, we
paragraph-aligned
But was is a paragraph? Is that an x86 term?
The term paragraph is used by the SMBIOS spec.
The reason why non-UEFI x86 requires low addresses (< 1MiB) for tables is that booting starts in real-mode.
Any memory address evenly divisible by 16 is called a paragraph boundary. [1]
[1] Memory Paragraphs in Real Mode http://www.c-jump.com/CIS77/ASM/Memory/M77_0080_paragraphs.htm
A segment begins on a paragraph boundary, which is an address divisible by decimal 16 or hex 10. [2]
[2] Programming with 8086 microprocessor https://www.uobabylon.edu.iq/eprints/publication_1_2613_35.pdf
Best regards
Heinrich
should implement the address rounding in write_tables() and not in table specific routines like copy_pirq_routing_table().
Add paragraph alignment in write_tables().
Signed-off-by: Heinrich Schuchardt heinrich.schuchardt@canonical.com
arch/x86/lib/tables.c | 2 ++ 1 file changed, 2 insertions(+)
Reviewed-by: Simon Glass sjg@chromium.org
diff --git a/arch/x86/lib/tables.c b/arch/x86/lib/tables.c index 5b5070f7ca..89d4d30a6a 100644 --- a/arch/x86/lib/tables.c +++ b/arch/x86/lib/tables.c @@ -97,6 +97,8 @@ int write_tables(void) int size = table->size ? : CONFIG_ROM_TABLE_SIZE; u32 rom_table_end;
rom_addr = ALIGN(rom_addr, 16);if (!strcmp("smbios", table->name)) gd->arch.smbios_start = rom_addr;-- 2.43.0
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Heinrich Schuchardt -
Simon Glass