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authorScott Duplichan <scott@notabs.org>2010-11-13 19:07:59 +0000
committerScott Duplichan <scott@notabs.org>2010-11-13 19:07:59 +0000
commitf3cce2f3c4ff4af4a386bddd49c92a55ad9cefa2 (patch)
tree2961bfdba8f650fca44d04fe1232c76c71adda05 /src/cpu/x86/mtrr
parent5960fb3dbd5c942d3c11f06dcd0c55f940444260 (diff)
downloadcoreboot-f3cce2f3c4ff4af4a386bddd49c92a55ad9cefa2.tar.xz
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
Diffstat (limited to 'src/cpu/x86/mtrr')
-rw-r--r--src/cpu/x86/mtrr/mtrr.c49
1 files changed, 31 insertions, 18 deletions
diff --git a/src/cpu/x86/mtrr/mtrr.c b/src/cpu/x86/mtrr/mtrr.c
index d44687a0e9..734734a77b 100644
--- a/src/cpu/x86/mtrr/mtrr.c
+++ b/src/cpu/x86/mtrr/mtrr.c
@@ -230,7 +230,8 @@ static unsigned fixed_mtrr_index(unsigned long addrk)
static unsigned int range_to_mtrr(unsigned int reg,
unsigned long range_startk, unsigned long range_sizek,
- unsigned long next_range_startk, unsigned char type, unsigned address_bits)
+ unsigned long next_range_startk, unsigned char type,
+ unsigned int address_bits, unsigned int above4gb)
{
if (!range_sizek) {
/* If there's no MTRR hole, this function will bail out
@@ -263,7 +264,12 @@ static unsigned int range_to_mtrr(unsigned int reg,
(type==MTRR_TYPE_UNCACHEABLE)?"UC":
((type==MTRR_TYPE_WRBACK)?"WB":"Other")
);
- set_var_mtrr(reg++, range_startk, sizek, type, address_bits);
+
+ /* if range is above 4GB, MTRR is needed
+ * only if above4gb flag is set
+ */
+ if (range_startk < 0x100000000ull / 1024 || above4gb)
+ set_var_mtrr(reg++, range_startk, sizek, type, address_bits);
range_startk += sizek;
range_sizek -= sizek;
if (reg >= BIOS_MTRRS) {
@@ -308,10 +314,9 @@ static void set_fixed_mtrr_resource(void *gp, struct device *dev, struct resourc
struct var_mtrr_state {
unsigned long range_startk, range_sizek;
unsigned int reg;
-#if CONFIG_VAR_MTRR_HOLE
unsigned long hole_startk, hole_sizek;
-#endif
- unsigned address_bits;
+ unsigned int address_bits;
+ unsigned int above4gb; /* Set if MTRRs are needed for DRAM above 4GB */
};
void set_var_mtrr_resource(void *gp, struct device *dev, struct resource *res)
@@ -344,17 +349,17 @@ void set_var_mtrr_resource(void *gp, struct device *dev, struct resource *res)
}
#endif
state->reg = range_to_mtrr(state->reg, state->range_startk,
- state->range_sizek, basek, MTRR_TYPE_WRBACK, state->address_bits);
+ state->range_sizek, basek, MTRR_TYPE_WRBACK,
+ state->address_bits, state->above4gb);
#if CONFIG_VAR_MTRR_HOLE
state->reg = range_to_mtrr(state->reg, state->hole_startk,
- state->hole_sizek, basek, MTRR_TYPE_UNCACHEABLE, state->address_bits);
+ state->hole_sizek, basek, MTRR_TYPE_UNCACHEABLE,
+ state->address_bits, state->above4gb);
#endif
state->range_startk = 0;
state->range_sizek = 0;
-#if CONFIG_VAR_MTRR_HOLE
- state->hole_startk = 0;
- state->hole_sizek = 0;
-#endif
+ state->hole_startk = 0;
+ state->hole_sizek = 0;
}
/* Allocate an msr */
printk(BIOS_SPEW, " Allocate an msr - basek = %08lx, sizek = %08lx,\n", basek, sizek);
@@ -388,12 +393,15 @@ void x86_setup_fixed_mtrrs(void)
}
-void x86_setup_var_mtrrs(unsigned address_bits)
+void x86_setup_var_mtrrs(unsigned int address_bits, unsigned int above4gb)
/* this routine needs to know how many address bits a given processor
* supports. CPUs get grumpy when you set too many bits in
* their mtrr registers :( I would generically call cpuid here
* and find out how many physically supported but some cpus are
* buggy, and report more bits then they actually support.
+ * If above4gb flag is set, variable MTRR ranges must be used to
+ * set cacheability of DRAM above 4GB. If above4gb flag is clear,
+ * some other mechanism is controlling cacheability of DRAM above 4GB.
*/
{
/* Try this the simple way of incrementally adding together
@@ -408,34 +416,38 @@ void x86_setup_var_mtrrs(unsigned address_bits)
*/
var_state.range_startk = 0;
var_state.range_sizek = 0;
-#if CONFIG_VAR_MTRR_HOLE
var_state.hole_startk = 0;
var_state.hole_sizek = 0;
-#endif
var_state.reg = 0;
var_state.address_bits = address_bits;
+ var_state.above4gb = above4gb;
search_global_resources(
IORESOURCE_MEM | IORESOURCE_CACHEABLE, IORESOURCE_MEM | IORESOURCE_CACHEABLE,
set_var_mtrr_resource, &var_state);
+
#if (CONFIG_GFXUMA == 1) /* UMA or SP. */
- // For now we assume the UMA space is at the end of memory
+ /* For now we assume the UMA space is at the end of memory below 4GB */
if (var_state.hole_startk || var_state.hole_sizek) {
printk(BIOS_DEBUG, "Warning: Can't set up MTRR hole for UMA due to pre-existing MTRR hole.\n");
} else {
+#if CONFIG_VAR_MTRR_HOLE
// Increase the base range and set up UMA as an UC hole instead
var_state.range_sizek += (uma_memory_size >> 10);
var_state.hole_startk = (uma_memory_base >> 10);
var_state.hole_sizek = (uma_memory_size >> 10);
+#endif
}
#endif
/* Write the last range */
var_state.reg = range_to_mtrr(var_state.reg, var_state.range_startk,
- var_state.range_sizek, 0, MTRR_TYPE_WRBACK, var_state.address_bits);
+ var_state.range_sizek, 0, MTRR_TYPE_WRBACK,
+ var_state.address_bits, var_state.above4gb);
#if CONFIG_VAR_MTRR_HOLE
var_state.reg = range_to_mtrr(var_state.reg, var_state.hole_startk,
- var_state.hole_sizek, 0, MTRR_TYPE_UNCACHEABLE, var_state.address_bits);
+ var_state.hole_sizek, 0, MTRR_TYPE_UNCACHEABLE,
+ var_state.address_bits, var_state.above4gb);
#endif
printk(BIOS_DEBUG, "DONE variable MTRRs\n");
printk(BIOS_DEBUG, "Clear out the extra MTRR's\n");
@@ -449,10 +461,11 @@ void x86_setup_var_mtrrs(unsigned address_bits)
post_code(0x6A);
}
+
void x86_setup_mtrrs(unsigned address_bits)
{
x86_setup_fixed_mtrrs();
- x86_setup_var_mtrrs(address_bits);
+ x86_setup_var_mtrrs(address_bits, 1);
}