LoongArch: Fix wrong "ROM Size" of boardinfo
authorTiezhu Yang <yangtiezhu@loongson.cn>
Thu, 21 Jul 2022 09:53:01 +0000 (17:53 +0800)
committerHuacai Chen <chenhuacai@loongson.cn>
Fri, 29 Jul 2022 10:22:33 +0000 (18:22 +0800)
We can see the "ROM Size" is different in the following outputs:

[root@linux loongson]# cat /sys/firmware/loongson/boardinfo
BIOS Information
Vendor                  : Loongson
Version                 : vUDK2018-LoongArch-V2.0.pre-beta8
ROM Size                : 63 KB
Release Date            : 06/15/2022

Board Information
Manufacturer            : Loongson
Board Name              : Loongson-LS3A5000-7A1000-1w-A2101
Family                  : LOONGSON64

[root@linux loongson]# dmidecode | head -11
...
Handle 0x0000, DMI type 0, 26 bytes
BIOS Information
Vendor: Loongson
Version: vUDK2018-LoongArch-V2.0.pre-beta8
Release Date: 06/15/2022
ROM Size: 4 MB

According to "BIOS Information (Type 0) structure" in the SMBIOS
Reference Specification [1], it shows 64K * (n+1) is the size of
the physical device containing the BIOS if the size is less than
16M.

Additionally, we can see the related code in dmidecode [2]:

  u64 s = { .l = (code1 + 1) << 6 };

So the output of dmidecode is correct, the output of boardinfo
is wrong, fix it.

By the way, at present no need to consider the size is 16M or
greater on LoongArch, because it is usually 4M or 8M which is
enough to use.

[1] https://www.dmtf.org/sites/default/files/standards/documents/DSP0134_3.6.0.pdf
[2] https://git.savannah.nongnu.org/cgit/dmidecode.git/tree/dmidecode.c#n347

Fixes: 628c3bb40e9a ("LoongArch: Add boot and setup routines")
Reviewed-by: WANG Xuerui <git@xen0n.name>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
arch/loongarch/kernel/setup.c

index c74860b53375a51ddab0b9ea4bf5787f7202ac38..8f5c2f9a1a835de4435cec1a5e92439387017697 100644 (file)
@@ -126,7 +126,7 @@ static void __init parse_bios_table(const struct dmi_header *dm)
        char *dmi_data = (char *)dm;
 
        bios_extern = *(dmi_data + SMBIOS_BIOSEXTERN_OFFSET);
-       b_info.bios_size = *(dmi_data + SMBIOS_BIOSSIZE_OFFSET);
+       b_info.bios_size = (*(dmi_data + SMBIOS_BIOSSIZE_OFFSET) + 1) << 6;
 
        if (bios_extern & LOONGSON_EFI_ENABLE)
                set_bit(EFI_BOOT, &efi.flags);