在 2023/8/21 09:29, Jiajie Chen 写道: > > On 2023/8/21 09:24, bibo mao wrote: >> + Add xianglai >> >> Good catch. >> >> In theory, it is logical id, and it can be not equal to physical id. >> However it must be equal to _UID in cpu dsdt table which is missing >> now. > > Yes, the logical id can be different from index. The spec says: > > If the processor structure represents an actual processor, this field must > match the value of ACPI processor ID field in the processor’s entry in the > MADT. If the processor structure represents a group of associated processors, > the structure might match a processor container in the name space. In that > case this entry will match the value of the _UID method of the associated > processor container. Where there is a match it must be represented. The flags > field, described in /Processor Structure Flags/, includes a bit to describe > whether the ACPI processor ID is valid. > > I believe PPTT, MADT and DSDT should all adhere to the same logical id > mapping. yes, you are right and I had a mistake.
Logical id in MADT/DSDT/PPTT should be the same, there is physical id associated with arch_ids->cpus[i].arch_id already. And get_arch_id for cpuclass to get physical id and DSDT table are missing about LoongArch platform, however it is another issue. Reviewed-by: Bibo Mao <maob...@loongson.cn> Regards Bibo Mao > >> Can pptt table parse error be fixed if cpu dsdt table is added? >> >> Regards >> Bibo Mao >> >> >> 在 2023/8/20 18:56, Jiajie Chen 写道: >>> In hw/acpi/aml-build.c:build_pptt() function, the code assumes that the >>> ACPI processor id equals to the cpu index, for example if we have 8 >>> cpus, then the ACPI processor id should be in range 0-7. >>> >>> However, in hw/loongarch/acpi-build.c:build_madt() function we broke the >>> assumption. If we have 8 cpus again, the ACPI processor id in MADT table >>> would be in range 1-8. It violates the following description taken from >>> ACPI spec 6.4 table 5.138: >>> >>> If the processor structure represents an actual processor, this field >>> must match the value of ACPI processor ID field in the processor’s entry >>> in the MADT. >>> >>> It will break the latest Linux 6.5-rc6 with the >>> following error message: >>> >>> ACPI PPTT: PPTT table found, but unable to locate core 7 (8) >>> Invalid BIOS PPTT >>> >>> Here 7 is the last cpu index, 8 is the ACPI processor id learned from >>> MADT. >>> >>> With this patch, Linux can properly detect SMT threads when "-smp >>> 8,sockets=1,cores=4,threads=2" is passed: >>> >>> Thread(s) per core: 2 >>> Core(s) per socket: 2 >>> Socket(s): 2 >>> >>> The detection of number of sockets is still wrong, but that is out of >>> scope of the commit. >>> >>> Signed-off-by: Jiajie Chen <c...@jia.je> >>> --- >>> hw/loongarch/acpi-build.c | 2 +- >>> 1 file changed, 1 insertion(+), 1 deletion(-) >>> >>> diff --git a/hw/loongarch/acpi-build.c b/hw/loongarch/acpi-build.c >>> index 0b62c3a2f7..ae292fc543 100644 >>> --- a/hw/loongarch/acpi-build.c >>> +++ b/hw/loongarch/acpi-build.c >>> @@ -127,7 +127,7 @@ build_madt(GArray *table_data, BIOSLinker *linker, >>> LoongArchMachineState *lams) >>> build_append_int_noprefix(table_data, 17, 1); /* Type */ >>> build_append_int_noprefix(table_data, 15, 1); /* Length */ >>> build_append_int_noprefix(table_data, 1, 1); /* Version */ >>> - build_append_int_noprefix(table_data, i + 1, 4); /* ACPI Processor >>> ID */ >>> + build_append_int_noprefix(table_data, i, 4); /* ACPI Processor >>> ID */ >>> build_append_int_noprefix(table_data, arch_id, 4); /* Core ID */ >>> build_append_int_noprefix(table_data, 1, 4); /* Flags */ >>> }
