Patch set updated for coreboot: nb/amd/amdht: Fix XCS buffer count setup on AMD Family 15h CPUs

[Timothy Pearson]

Timothy Pearson ([e-mail]) just uploaded a new patch set to gerrit, which you can find at https://review.coreboot.org/12070

-gerrit

commit d8dc5032c92fb83afb1c4b0f9ce564a394d70bfd
Author: Timothy Pearson 
Date:   Mon Sep 7 18:07:43 2015 -0500

nb/amd/amdht: Fix XCS buffer count setup on AMD Family 15h CPUs

The existing code re-used the Family 10h XCS buffer setup on
    Family 15h CPUs, which set incorrect values leading to random
    system lockups.

Use the Family 15h XCS buffer setup shown in the BKDG.

Change-Id: Ie4bc8b3ea6b110bc507beda025de53d828118f55
    Signed-off-by: Timothy Pearson 
---
 src/northbridge/amd/amdht/h3ncmn.c | 94 +++++++++++++++++++++++++++++++++++++-
 1 file changed, 92 insertions(+), 2 deletions(-)

diff --git a/src/northbridge/amd/amdht/h3ncmn.c b/src/northbridge/amd/amdht/h3ncmn.c
index 7937c6e..cbe90e0 100644
--- a/src/northbridge/amd/amdht/h3ncmn.c
+++ b/src/northbridge/amd/amdht/h3ncmn.c
@@ -2,6 +2,7 @@
  * This file is part of the coreboot project.
  *
  * Copyright (C) 2007 Advanced Micro Devices, Inc.
+ * Copyright (C) 2015 Timothy Pearson , Raptor Engineering
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -1389,6 +1390,75 @@ static uint32_t fam10NorthBridgeFreqMask(u8 node, cNorthBridge *nb)

/***************************************************************************//**
  *
+ * static u16
+ * fam15NorthBridgeFreqMask(u8 NodeID, cNorthBridge *nb)
+ *
+ *  Description:
+ *	Return a mask that eliminates HT frequencies that cannot be used due to a slow
+ *	northbridge frequency.
+ *
+ *  Parameters:
+ *	@param[in]  node     = Result could (later) be for a specific node
+ *	@param[in]  *nb      = this northbridge
+ *	@return  = Frequency mask
+ *
+ ******************************************************************************/
+static uint32_t fam15NorthBridgeFreqMask(u8 node, cNorthBridge *nb)
+{
+	u8 nbCOF;
+	uint32_t supported;
+
+	nbCOF = getMinNbCOF();
+	/*
+	 * nbCOF is minimum northbridge speed in hundreds of MHz.
+	 * HT can not go faster than the minimum speed of the northbridge.
+	 */
+	if ((nbCOF >= 6) && (nbCOF < 10))
+	{
+		/* Generation 1 HT link frequency */
+		/* Convert frequency to bit and all less significant bits,
+		 * by setting next power of 2 and subtracting 1.
+		 */
+		supported = ((uint32_t)1 << ((nbCOF >> 1) + 2)) - 1;
+	}
+	else if ((nbCOF >= 10) && (nbCOF <= 32))
+	{
+		/* Generation 3 HT link frequency
+		 * Assume error retry is enabled on all Gen 3 links
+		 */
+		nbCOF *= 2;
+		if (nbCOF > 32)
+			nbCOF = 32;
+
+		/* Convert frequency to bit and all less significant bits,
+		 * by setting next power of 2 and subtracting 1.
+		 */
+		supported = ((uint32_t)1 << ((nbCOF >> 1) + 2)) - 1;
+	}
+	else if (nbCOF > 32)
+	{
+		supported = HT_FREQUENCY_LIMIT_3200M;
+	}
+	/* unlikely cases, but include as a defensive measure, also avoid trick above */
+	else if (nbCOF == 4)
+	{
+		supported = HT_FREQUENCY_LIMIT_400M;
+	}
+	else if (nbCOF == 2)
+	{
+		supported = HT_FREQUENCY_LIMIT_200M;
+	}
+	else
+	{
+		STOP_HERE;
+		supported = HT_FREQUENCY_LIMIT_200M;
+	}
+
+	return (fixEarlySampleFreqCapability(supported));
+}
+
+/***************************************************************************//**
+ *
  * static void
  * gatherLinkData(sMainData *pDat, cNorthBridge *nb)
  *
@@ -2266,6 +2336,26 @@ static void fam10BufferOptimizations(u8 node, sMainData *pDat, cNorthBridge *nb)
    }
 }

+/***************************************************************************//**
+ *
+ * static void
+ * fam15BufferOptimizations(u8 node, sMainData *pDat, cNorthBridge *nb)
+ *
+ *  Description:
+ *	 Buffer tunings are inherently northbridge specific. Check for specific configs
+ *	 which require adjustments and apply any standard workarounds to this node.
+ *
+ *  Parameters:
+ *	@param[in] node       = the node to tune
+ *	@param[in] *pDat  = global state
+ *	@param[in] nb = this northbridge
+ *
+ ******************************************************************************/
+static void fam15BufferOptimizations(u8 node, sMainData *pDat, cNorthBridge *nb)
+{
+	/* Buffer count setup on Family 15h is currently handled in cpuSetAMDPCI */
+}
+
 /*
  * North Bridge 'constructor'.
  *
@@ -2324,11 +2414,11 @@ void newNorthBridge(u8 node, cNorthBridge *nb)
    	ht3SetCFGAddrMap,
    	convertBitsToWidth,
    	convertWidthToBits,
-		fam10NorthBridgeFreqMask,
+		fam15NorthBridgeFreqMask,
    	gatherLinkData,
    	setLinkData,
    	ht3WriteTrafficDistribution,
-		fam10BufferOptimizations,
+		fam15BufferOptimizations,
    	0x00000001,
    	0x00000200,
    	18,