Hi all,
I am working with a Tyan S2912 board and fam10 Opterons and recently updated my coreboot environment. I stumbled across an error which I thought was already removed a while ago. The HT link offsets reported by function "AMD_CpuFindCapability" in init_cpus.c are not correct (they always evaluate to 0x08) and therefore do not comply with link offsets as specified by AMDs BKDG. Below is a simple fix which produces correct behavior - at least on my box. Dont know what side effects this might have on systems other than the PHY electrical settings and erratas not getting applied.
Best regards,
Maximilian Thuermer
Index: src/cpu/amd/model_10xxx/init_cpus.c =================================================================== --- src/cpu/amd/model_10xxx/init_cpus.c (revision 5256) +++ src/cpu/amd/model_10xxx/init_cpus.c (working copy) @@ -702,29 +702,32 @@ */ BOOL AMD_CpuFindCapability (u8 node, u8 cap_count, u8 *offset) { + u32 reg; u32 val; - + /* get start of CPU HT Host Capabilities */ val = pci_read_config32(NODE_PCI(node, 0), 0x34); - val &= 0xFF; + val &= 0xFF; //reg offset of first link
cap_count++;
/* Traverse through the capabilities. */ do { - val = pci_read_config32(NODE_PCI(node, 0), val); + reg = pci_read_config32(NODE_PCI(node, 0), val); /* Is the capability block a HyperTransport capability block? */ - if ((val & 0xFF) == 0x08) { + if ((reg & 0xFF) == 0x08) { /* Is the HT capability block an HT Host Capability? */ - if ((val & 0xE0000000) == (1 << 29)) + if ((reg & 0xE0000000) == (1 << 29)) cap_count--; } - if (cap_count) - val = (val >> 8) & 0xFF; + + if(cap_count) + val = (reg >> 8) & 0xFF; //update reg offset } while (cap_count && val);
*offset = (u8) val;
+ /* If requested capability found val != 0 */ if (!cap_count) return TRUE;