MTRR related improvements for AMD family 10h and family 0Fh systems

-- When building for UMA, reduce the limit for DRAM below 4GB
   from E0000000 to C0000000. This is needed to accomodate the
   UMA frame buffer.
-- Correct problem where msr C0010010 bits 21 and 22 (MtrrTom2En
   and Tom2ForceMemTypeWB) are not set consistently across cores.
-- Enable TOM2 only if DRAM is present above 4GB.
-- Use AMD Tom2ForceMemTypeWB feature to avoid the need for 
   variable MTRR ranges above 4GB.
-- Add above4gb flag argument to function x86_setup_var_mtrrs. Clearing
   this flag causes x86_setup_var_mtrrs() to omit MTRR ranges for
   DRAM above 4GB. AMD systems use this option to conserve MTRRs.
-- Northbridge.c change to deduct UMA memory from DRAM size reported
   by ram_resource. This corrects a problem where mtrr.c generates an
   unexpected variable MTRR range.
-- Correct problem causing build failure when CONFIG_GFXUMA=1 and
   CONFIG_VAR_MTRR_HOLE=0.
-- Reserve the UMA DRAM range for AMD K8 as is already done for AMD
   family 10h.
Tested with mahogany on ECS A780G-GM with 2GB and 4GB.
Tested with mahogany_fam10 on ECS A780G-GM with 2GB and 4GB.
 
Signed-off-by: Scott Duplichan <scott@notabs.org>
Acked-by: Peter Stuge <peter@stuge.se>

git-svn-id: svn://svn.coreboot.org/coreboot/trunk@6067 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1

1 files changed, 24 insertions, 2 deletions

diff --git a/src/northbridge/amd/amdk8/northbridge.c b/src/northbridge/amd/amdk8/northbridge.c
index 263777f751..1f98684c6b 100644
--- a/src/northbridge/amd/amdk8/northbridge.c
+++ b/src/northbridge/amd/amdk8/northbridge.c
@@ -822,11 +822,24 @@ static u32 hoist_memory(unsigned long hole_startk, int node_id)
 #endif
 
 #if CONFIG_WRITE_HIGH_TABLES==1
-#define HIGH_TABLES_SIZE 64	// maximum size of high tables in KB
+#define HIGH_TABLES_SIZE 64	/* maximum size of high tables in KB */
 extern uint64_t high_tables_base, high_tables_size;
+#endif
+
 #if CONFIG_GFXUMA == 1
 extern uint64_t uma_memory_base, uma_memory_size;
-#endif
+
+static void add_uma_resource(struct device *dev, int index)
+{
+	struct resource *resource;
+
+	printk(BIOS_DEBUG, "Adding UMA memory area\n");
+	resource = new_resource(dev, index);
+	resource->base = (resource_t) uma_memory_base;
+	resource->size = (resource_t) uma_memory_size;
+	resource->flags = IORESOURCE_MEM | IORESOURCE_RESERVE |
+		IORESOURCE_FIXED | IORESOURCE_STORED | IORESOURCE_ASSIGNED;
+}
 #endif
 
 static void amdk8_domain_set_resources(device_t dev)
@@ -1040,6 +1053,11 @@ static void amdk8_domain_set_resources(device_t dev)
 		/* If sizek == 0, it was split at mmio_basek without a hole.
 		 * Don't create an empty ram_resource.
 		 */
+#if CONFIG_GFXUMA == 1
+		/* Deduct uma memory before reporting because
+		 * this is what the mtrr code expects */
+		sizek -= uma_memory_size / 1024;
+#endif
 		if (sizek)
 			ram_resource(dev, (idx | i), basek, sizek);
 		idx += 0x10;
@@ -1057,6 +1075,10 @@ static void amdk8_domain_set_resources(device_t dev)
 		}
 #endif
 	}
+
+#if CONFIG_GFXUMA == 1
+	add_uma_resource(dev, 7);
+#endif
 	assign_resources(dev->link_list);
 
 }