[PATCH 3/5] smbios: Use SMBIOS 3.0 to support an address above 4GB

[Caleb Connolly]

On 18/10/2023 04:33, Simon Glass wrote:
> Hi Caleb,
> 
> On Tue, 17 Oct 2023 at 11:59, Caleb Connolly <caleb.connolly at linaro.org> wrote:
>>
>> Hi Both,
>>
>> [...]
>>>>>
>>>>> @@ -513,13 +517,23 @@ ulong write_smbios_table(ulong addr)
>>>>>        */
>>>>>       table_addr = (ulong)map_sysmem(tables, 0);
>>>>>       if (sizeof(table_addr) > sizeof(u32) && table_addr > (ulong)UINT_MAX) {
>>>>
>>>> You have to check the end address of the table not the start address here.
>>>>
>>>> The SMBIOS specification says that you should always supply a 32bit
>>>> SMBIOS entry point. Of course this is not possible on boards that don't
>>>> have low memory.
>>>>
>>>> In install_smbios_table() this can be achieved by calling
>>>> efi_allocate_pages() with EFI_MAX_ALLOCATE_TYPE and a maximum address of
>>>> 4 GiB - 1. Only if this fails use high memory.
>>>
>>> Hmm perhaps we need a way to allocate memory below 4GB in U-Boot? How
>>> does this EFI function work?
>>
>> Yes, prior to 53fab13a7b11 ("efi: Use the installed SMBIOS tables")
>> efi_allocate_pages() was called directly from efi_smbios_register(). My
>> boards all malloc() memory above the 4GB boundary and I just recently
>> rebased and hit a regression caused by this.
>>
>> In my testing, calling efi_allocate_pages() from install_smbios_table()
>> did work, but I figure that's probably not intended behaviour...
>>
>> I can confirm that this series does allow my boards to boot again, but
>> dmidecode is unable to decode the SMBIOS 3.0 table (even with
>> STRICT_DEVMEM disabled fwiw).
> 
> OK thank you for digging into this. So I suppose I can repeat that in
> qemu, with a suitable distro?

I would assume so, I'm running Alpine in my testing. I'd be more than
happy to test any patches as well.
> 
>>
>> Below is EFI and board memory map info after applying this patch series.
>>
>> => efidebug tables
>> Cannot read EFI system partition
>> Cannot read EFI system partition
>> Failed to persist EFI variables
>> 000000017ea22040  32313633-3532-3634-2d66-3765662d3463  EFI Conformance
>> Profiles Table
>> 000000017ea21040  36366265-3139-6138-2d37-6565662d3430  Runtime properties
>> 000000017fb13000  64663266-3531-3434-2d39-3739342d3461  (unknown)
>> => efidebug memmap
>> Type             Start            End              Attributes
>> ================ ================ ================ ==========
>> CONVENTIONAL     0000000080000000-000000017ea1f000 WB
>> BOOT DATA        000000017ea1f000-000000017ea21000 WB
>> RUNTIME DATA     000000017ea21000-000000017ea22000 WB|RT
>> BOOT DATA        000000017ea22000-000000017ea23000 WB
>> RUNTIME DATA     000000017ea23000-000000017ea25000 WB|RT
>> BOOT DATA        000000017ea25000-000000017ea26000 WB
>> RUNTIME DATA     000000017ea26000-000000017ea36000 WB|RT
>> BOOT DATA        000000017ea36000-000000017eaef000 WB
>> BOOT CODE        000000017eaef000-000000017fb13000 WB
>> RUNTIME DATA     000000017fb13000-000000017fb14000 WB|RT
>> BOOT CODE        000000017fb14000-000000017ff20000 WB
>> RUNTIME CODE     000000017ff20000-000000017ff30000 WB|RT
>> BOOT CODE        000000017ff30000-0000000180000000 WB
>> BOOT DATA        0000000180000000-000000027c7a0000 WB
>> => bdinfo
>> boot_params = 0x0000000000000000
>> DRAM bank   = 0x0000000000000000
>> -> start    = 0x0000000080000000
>> -> size     = 0x0000000100000000
>> DRAM bank   = 0x0000000000000001
>> -> start    = 0x0000000180000000
>> -> size     = 0x00000000fc7a0000
>> flashstart  = 0x0000000000000000
>> flashsize   = 0x0000000000000000
>> flashoffset = 0x0000000000000000
>> baudrate    = 115200 bps
>> relocaddr   = 0x000000017ff26000
>> reloc off   = 0x000000017ff26000
>> Build       = 64-bit
>> fdt_blob    = 0x000000017faef6c0
>> new_fdt     = 0x000000017faef6c0
>> fdt_size    = 0x0000000000017680
>> Video       = framebuffer at 9D400000 active
>> FB base     = 0x000000009d400000
>> FB size     = 1080x2160x32
>> lmb_dump_all:
>>  memory.cnt = 0x1 / max = 0x40
>>  memory[0]      [0x80000000-0x27c79ffff], 0x1fc7a0000 bytes flags: 0
>>  reserved.cnt = 0x7 / max = 0x40
>>  reserved[0]    [0x85700000-0x85cfffff], 0x00600000 bytes flags: 4
>>  reserved[1]    [0x85e00000-0x85efffff], 0x00100000 bytes flags: 4
>>  reserved[2]    [0x85fc0000-0x890fffff], 0x03140000 bytes flags: 4
>>  reserved[3]    [0x8ab00000-0x8c416fff], 0x01917000 bytes flags: 4
>>  reserved[4]    [0x8c500000-0x97bfffff], 0x0b700000 bytes flags: 4
>>  reserved[5]    [0x9d400000-0x9f7fffff], 0x02400000 bytes flags: 4
>>  reserved[6]    [0x17ea1f000-0x27c79ffff], 0xfdd81000 bytes flags: 0
>> devicetree  = board
>> arch_number = 0x0000000000000000
>> TLB addr    = 0x000000017fff0000
>> irq_sp      = 0x000000017faef6b0
>> sp start    = 0x000000017faef6b0
>> Early malloc usage: a78 / 2000
>>>
>>> I don't think EFI has been set up by the time this function is called.
>>>
>>> Regards,
>>> Simon
>>
>> --
>> // Caleb (they/them)
> 
> Regards,
> Simon

-- 
// Caleb (they/them)