On Sat, Aug 11, 2018 at 3:56 PM, Michael Jin [off-list ref] wrote:

On Sat, Aug 11, 2018 at 9:30 AM, Pu Wen [off-list ref] wrote:

quoted

@@ -1051,6 +1065,16 @@ static void determine_memory_type(struct amd64_pvt *pvt)
                else
                        pvt->dram_type = MEM_DDR4;
                return;
+       case 0x18:
+               if (pvt->vendor == X86_VENDOR_HYGON) {

This vendor checking is not necessary as there are no other known
family 18h processors.

Actually, vendor checking works here. Although, AMD has not released a
family 18h yet.