[PATCH] x86: Add Hygon Dhyana support.

[Jinke Fan]

On 12/11/2018 11:15 AM, Carlos O'Donell wrote:
> On 12/10/18 5:26 AM, fanjinke wrote:
>> This patch fix Hygon Dhyana processor CPU Vendor ID detection problem
>> in glibc sysdep module, current glibc codes doesn't recognize Dhyana
>> CPU Vendor ID("HygonGenuine") and set kind to arch_kind_other, which
>> result to incorrect zero value for __cache_sysconf() syscall. As Hygon
>> Dhyana share most architecture feature as AMD Family 17h, this patch
>> add Hygon CPU Vendor ID check and setup kind to arch_kind_amd and reuse
>> AMD code path, which lead to correct return value in __cache_sysconf()
>> syscall. we run the glibc test suite for both Hygon Dhyana and AMD EPYC
>> and found no failure case.
>>
>> Background:
>> Chengdu Haiguang IC Design Co., Ltd (Hygon) is a Joint Venture between
>> AMD and Haiguang Information Technology Co.,Ltd., aims at providing high
>> performance x86 processor for China server market. Its first generation
>> processor codename is Dhyana, which originates from AMD technology and
>> shares most of the architecture with AMD's family 17h, but with different
>> CPU Vendor ID("HygonGenuine")/Family series number(Family 18h).
>>
>> Related Hygon kernel patch can be found on
>> http://lkml.kernel.org/r/5ce86123a7b9dad925ac583d88d2f921040e859b.
>> 1538583282.git.puwen@hygon.cn
>>
>> Very appreciate everyone who has helped review and fix issues.
> Do you have copyright assignment papers filed with the FSF?
>
> This one-line change doesn't need copyright papers filed, but if
> you need to make more compilcated changes, then you will need
> them.
>
>> *Tested for Hygon:*
>> Before patching the results of hygon's tests:
>> Summary of test results:
>>        6 FAIL
>>     5927 PASS
>>       29 UNSUPPORTED
>>       17 XFAIL
>>        2 XPASS
>> Makefile:403: recipe for target 'tests' failed
>> make[1]: *** [tests] Error 1
>> make[1]: Leaving directory
>> '/home/higon/space/src/opensrc/glibc/glibc/glibc'
>> Makefile:9: recipe for target 'check' failed
>> make: *** [check] Error 2
>>
>> And the result of testing after patching:
>> Summary of test results:
>>     5945 PASS
>>       17 UNSUPPORTED
>>       17 XFAIL
>>        2 XPASS
>> make[1]: Leaving directory
>> '/home/higon/space/src/opensrc/glibc/glibc/glibc'
>>
>> *Tested for AMD:*
>> The test results did not change before and after patching:
>> Summary of test results:
>>     5951 PASS
>>       11 UNSUPPORTED
>>       17 XFAIL
>>        2 XPASS
>> make[1]: Leaving directory '/home/higon/glibc'
>>
>> ChangeLog:
>>
>> 2018-12-10  fanjinke<fanjinke@hygon.cn>
>>
>>          * sysdeps/x86/cpu-features.c (init_cpu_features):
>> ---
>>   sysdeps/x86/cpu-features.c | 5 +++--
>>   1 file changed, 3 insertions(+), 2 deletions(-)
>>
>> diff --git a/sysdeps/x86/cpu-features.c b/sysdeps/x86/cpu-features.c
>> index 5f9eefd408..86e78bfb78 100644
>> --- a/sysdeps/x86/cpu-features.c
>> +++ b/sysdeps/x86/cpu-features.c
>> @@ -425,8 +425,9 @@ init_cpu_features (struct cpu_features *cpu_features)
>>   	cpu_features->feature[index_arch_Prefer_No_AVX512]
>>   	  |= bit_arch_Prefer_No_AVX512;
>>       }
>> -  /* This spells out "AuthenticAMD".  */
>> -  else if (ebx == 0x68747541 && ecx == 0x444d4163 && edx == 0x69746e65)
>> +  /* This spells out "AuthenticAMD" or "HygonGenuine". */
>> +  else if ((ebx == 0x68747541 && ecx == 0x444d4163 && edx == 0x69746e65)
>> +	|| (ebx == 0x6f677948 && ecx == 0x656e6975 && edx == 0x6e65476e))
>>       {
>>         unsigned int extended_model;
>    
> This looks fine to me, and reuses the AMD code.
>
> I'd like to hear from Amit if this is OK for him, since he'll have to
> maintain this code as things diverge.
>
> Amit, Any objections?
>
> Reviewed-by: Carlos O'Donell<carlos@redhat.com>
>
Hi Carlos,

Thank you for your reply and reminder.

The copyright issue is already under processing.