Intel and GFXUMA: fix MTRR and use uma_resource()

Commit 2d42b340034ff005693482ef9ca34ce3e0f08371 changed the
variable MTRR setup and removed compensation of uma_memory_size in
the cacheable memory resources.

Since the cacheable region size was no longer divisible by a large
power of 2, like 256 MB, this caused excessive use of MTRRs.
As first symptoms, slow boot with grub and poor user response.

As a solution, register the actual top of low ram with ram_resource(),
and do not subtract the UMA/TSEG regions from it.

TSEG may require further work as the original did not appear exactly
right to begin with. To have UMA as un-cacheable, use uma_resource().

Change-Id: I4ca99b5c2ca4e474296590b3d0c6ef5d09550d80
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/1239
Reviewed-by: Anton Kochkov <anton.kochkov@gmail.com>
Tested-by: build bot (Jenkins)

1 files changed, 6 insertions, 5 deletions

diff --git a/src/northbridge/intel/i82810/northbridge.c b/src/northbridge/intel/i82810/northbridge.c
index 892fc28133..f6d14e0bd2 100644
--- a/src/northbridge/intel/i82810/northbridge.c
+++ b/src/northbridge/intel/i82810/northbridge.c
@@ -93,7 +93,7 @@ static void pci_domain_set_resources(device_t dev)
 	if (!mc_dev)
 		return;
 
-	unsigned long tomk;
+	unsigned long tomk, tomk_stolen;
 	int idx, drp_value;
 	u8 reg8;
 
@@ -123,21 +123,22 @@ static void pci_domain_set_resources(device_t dev)
 	tomk += (unsigned long)(translate_i82810_to_mb[drp_value]);
 	/* Convert tomk from MB to KB. */
 	tomk = tomk << 10;
-	tomk -= igd_memory;
+	tomk_stolen = tomk - igd_memory;
 
 	/* For reserving UMA memory in the memory map */
-	uma_memory_base = tomk * 1024ULL;
+	uma_memory_base = tomk_stolen * 1024ULL;
 	uma_memory_size = igd_memory * 1024ULL;
-	printk(BIOS_DEBUG, "Available memory: %ldKB\n", tomk);
+	printk(BIOS_DEBUG, "Available memory: %ldKB\n", tomk_stolen);
 
 	/* Report the memory regions. */
 	idx = 10;
 	ram_resource(dev, idx++, 0, 640);
 	ram_resource(dev, idx++, 768, tomk - 768);
+	uma_resource(dev, idx++, uma_memory_base >> 10, uma_memory_size >> 10);
 
 #if CONFIG_WRITE_HIGH_TABLES
 	/* Leave some space for ACPI, PIRQ and MP tables */
-	high_tables_base = (tomk * 1024) - HIGH_MEMORY_SIZE;
+	high_tables_base = (tomk_stolen * 1024) - HIGH_MEMORY_SIZE;
 	high_tables_size = HIGH_MEMORY_SIZE;
 #endif
 	assign_resources(dev->link_list);