This patch allows the user to select a maximum HyperTransport link frequency.
Speed capping is required for maximum stability when attempting to use new
HT3 CPUs on older HT1 mainboards, as the physical inter-CPU traces on the
mainboard may not be able to reliably handle the faster HT3 link
frequency.
---
Signed-off-by: Timothy Pearson <[email protected]>
Timothy Pearson
Raptor Engineering
Index: h3finit.c
===================================================================
--- src/northbridge/amd/amdht/h3finit.c (revision 5119)
+++ src/northbridge/amd/amdht/h3finit.c (working copy)
@@ -1327,7 +1327,25 @@
for (i = 0; i < pDat->TotalLinks*2; i += 2)
{
- cbPCBFreqLimit = 0xFFFF;
+#if CONFIG_LIMIT_HT_SPEED_200
+ cbPCBFreqLimit = 0x0001; // 200MHz
+#elif CONFIG_LIMIT_HT_SPEED_400
+ cbPCBFreqLimit = 0x0003; // 400MHz
+#elif CONFIG_LIMIT_HT_SPEED_600
+ cbPCBFreqLimit = 0x0007; // 600MHz
+#elif CONFIG_LIMIT_HT_SPEED_800
+ cbPCBFreqLimit = 0x000F; // 800MHz
+#elif CONFIG_LIMIT_HT_SPEED_1000
+ cbPCBFreqLimit = 0x001F; // 1.0GHz
+#elif CONFIG_LIMIT_HT_SPEED_1200
+ cbPCBFreqLimit = 0x003F; // 1.2GHz
+#elif CONFIG_LIMIT_HT_SPEED_1400
+ cbPCBFreqLimit = 0x007F; // 1.4GHz
+#elif CONFIG_LIMIT_HT_SPEED_1600
+ cbPCBFreqLimit = 0x00FF; // 1.6GHz
+#else
+ cbPCBFreqLimit = 0xFFFF; // Maximum allowed by autoconfiguration
+#endif
cbPCBABDownstreamWidth = 16;
cbPCBBAUpstreamWidth = 16;
--
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