[U-Boot] [PATCH v2 05/11] x86: Setup fixed range MTRRs for legacy regions

We should setup fixed range MTRRs for some legacy regions like VGA RAM and PCI ROM areas as uncacheable. Note FSP may setup these to other cache settings, but we can override this in x86_cpu_init_f().
Signed-off-by: Bin Meng bmeng.cn@gmail.com Acked-by: Simon Glass sjg@chromium.org ---
Changes in v2: None
arch/x86/cpu/cpu.c | 22 ++++++++++++++++++++++ arch/x86/include/asm/mtrr.h | 27 ++++++++++++++++----------- 2 files changed, 38 insertions(+), 11 deletions(-)
diff --git a/arch/x86/cpu/cpu.c b/arch/x86/cpu/cpu.c index d108ee5..9afdafb 100644 --- a/arch/x86/cpu/cpu.c +++ b/arch/x86/cpu/cpu.c @@ -28,6 +28,8 @@ #include <asm/cpu.h> #include <asm/lapic.h> #include <asm/mp.h> +#include <asm/msr.h> +#include <asm/mtrr.h> #include <asm/post.h> #include <asm/processor.h> #include <asm/processor-flags.h> @@ -352,6 +354,26 @@ int x86_cpu_init_f(void) gd->arch.has_mtrr = has_mtrr(); }
+ /* Configure fixed range MTRRs for some legacy regions */ + if (gd->arch.has_mtrr) { + u64 mtrr_cap; + + mtrr_cap = native_read_msr(MTRR_CAP_MSR); + if (mtrr_cap & MTRR_CAP_FIX) { + /* Mark the VGA RAM area as uncacheable */ + native_write_msr(MTRR_FIX_16K_A0000_MSR, 0, 0); + + /* Mark the PCI ROM area as uncacheable */ + native_write_msr(MTRR_FIX_4K_C0000_MSR, 0, 0); + native_write_msr(MTRR_FIX_4K_C8000_MSR, 0, 0); + native_write_msr(MTRR_FIX_4K_D0000_MSR, 0, 0); + native_write_msr(MTRR_FIX_4K_D8000_MSR, 0, 0); + + /* Enable the fixed range MTRRs */ + msr_setbits_64(MTRR_DEF_TYPE_MSR, MTRR_DEF_TYPE_FIX_EN); + } + } + return 0; }
diff --git a/arch/x86/include/asm/mtrr.h b/arch/x86/include/asm/mtrr.h index 3ad617c..70762ee 100644 --- a/arch/x86/include/asm/mtrr.h +++ b/arch/x86/include/asm/mtrr.h @@ -21,6 +21,11 @@ #define MTRR_CAP_MSR 0x0fe #define MTRR_DEF_TYPE_MSR 0x2ff
+#define MTRR_CAP_SMRR (1 << 11) +#define MTRR_CAP_WC (1 << 10) +#define MTRR_CAP_FIX (1 << 8) +#define MTRR_CAP_VCNT_MASK 0xff + #define MTRR_DEF_TYPE_EN (1 << 11) #define MTRR_DEF_TYPE_FIX_EN (1 << 10)
@@ -38,17 +43,17 @@ #define RANGES_PER_FIXED_MTRR 8 #define NUM_FIXED_RANGES (NUM_FIXED_MTRRS * RANGES_PER_FIXED_MTRR)
-#define MTRR_FIX_64K_00000_MSR 0x250 -#define MTRR_FIX_16K_80000_MSR 0x258 -#define MTRR_FIX_16K_A0000_MSR 0x259 -#define MTRR_FIX_4K_C0000_MSR 0x268 -#define MTRR_FIX_4K_C8000_MSR 0x269 -#define MTRR_FIX_4K_D0000_MSR 0x26a -#define MTRR_FIX_4K_D8000_MSR 0x26b -#define MTRR_FIX_4K_E0000_MSR 0x26c -#define MTRR_FIX_4K_E8000_MSR 0x26d -#define MTRR_FIX_4K_F0000_MSR 0x26e -#define MTRR_FIX_4K_F8000_MSR 0x26f +#define MTRR_FIX_64K_00000_MSR 0x250 +#define MTRR_FIX_16K_80000_MSR 0x258 +#define MTRR_FIX_16K_A0000_MSR 0x259 +#define MTRR_FIX_4K_C0000_MSR 0x268 +#define MTRR_FIX_4K_C8000_MSR 0x269 +#define MTRR_FIX_4K_D0000_MSR 0x26a +#define MTRR_FIX_4K_D8000_MSR 0x26b +#define MTRR_FIX_4K_E0000_MSR 0x26c +#define MTRR_FIX_4K_E8000_MSR 0x26d +#define MTRR_FIX_4K_F0000_MSR 0x26e +#define MTRR_FIX_4K_F8000_MSR 0x26f
#if !defined(__ASSEMBLER__)

On 6 July 2015 at 02:31, Bin Meng bmeng.cn@gmail.com wrote:
We should setup fixed range MTRRs for some legacy regions like VGA RAM and PCI ROM areas as uncacheable. Note FSP may setup these to other cache settings, but we can override this in x86_cpu_init_f().
Signed-off-by: Bin Meng bmeng.cn@gmail.com Acked-by: Simon Glass sjg@chromium.org
Changes in v2: None
arch/x86/cpu/cpu.c | 22 ++++++++++++++++++++++ arch/x86/include/asm/mtrr.h | 27 ++++++++++++++++----------- 2 files changed, 38 insertions(+), 11 deletions(-)
Applied to u-boot-x86, thanks!

Hi Bin,
On 6 July 2015 at 02:31, Bin Meng bmeng.cn@gmail.com wrote:
We should setup fixed range MTRRs for some legacy regions like VGA RAM and PCI ROM areas as uncacheable. Note FSP may setup these to other cache settings, but we can override this in x86_cpu_init_f().
Signed-off-by: Bin Meng bmeng.cn@gmail.com Acked-by: Simon Glass sjg@chromium.org
Changes in v2: None
arch/x86/cpu/cpu.c | 22 ++++++++++++++++++++++ arch/x86/include/asm/mtrr.h | 27 ++++++++++++++++----------- 2 files changed, 38 insertions(+), 11 deletions(-)
diff --git a/arch/x86/cpu/cpu.c b/arch/x86/cpu/cpu.c index d108ee5..9afdafb 100644 --- a/arch/x86/cpu/cpu.c +++ b/arch/x86/cpu/cpu.c @@ -28,6 +28,8 @@ #include <asm/cpu.h> #include <asm/lapic.h> #include <asm/mp.h> +#include <asm/msr.h> +#include <asm/mtrr.h> #include <asm/post.h> #include <asm/processor.h> #include <asm/processor-flags.h> @@ -352,6 +354,26 @@ int x86_cpu_init_f(void) gd->arch.has_mtrr = has_mtrr(); }
/* Configure fixed range MTRRs for some legacy regions */
if (gd->arch.has_mtrr) {
u64 mtrr_cap;
mtrr_cap = native_read_msr(MTRR_CAP_MSR);
if (mtrr_cap & MTRR_CAP_FIX) {
/* Mark the VGA RAM area as uncacheable */
native_write_msr(MTRR_FIX_16K_A0000_MSR, 0, 0);
/* Mark the PCI ROM area as uncacheable */
native_write_msr(MTRR_FIX_4K_C0000_MSR, 0, 0);
native_write_msr(MTRR_FIX_4K_C8000_MSR, 0, 0);
native_write_msr(MTRR_FIX_4K_D0000_MSR, 0, 0);
native_write_msr(MTRR_FIX_4K_D8000_MSR, 0, 0);
I just noticed that setting this up makes the Minnowmax ROM execution go really slowly. Do we need to turn off the cache? It goes from <1s to >4s.
/* Enable the fixed range MTRRs */
msr_setbits_64(MTRR_DEF_TYPE_MSR, MTRR_DEF_TYPE_FIX_EN);
}
}
return 0;
}
diff --git a/arch/x86/include/asm/mtrr.h b/arch/x86/include/asm/mtrr.h index 3ad617c..70762ee 100644 --- a/arch/x86/include/asm/mtrr.h +++ b/arch/x86/include/asm/mtrr.h @@ -21,6 +21,11 @@ #define MTRR_CAP_MSR 0x0fe #define MTRR_DEF_TYPE_MSR 0x2ff
+#define MTRR_CAP_SMRR (1 << 11) +#define MTRR_CAP_WC (1 << 10) +#define MTRR_CAP_FIX (1 << 8) +#define MTRR_CAP_VCNT_MASK 0xff
#define MTRR_DEF_TYPE_EN (1 << 11) #define MTRR_DEF_TYPE_FIX_EN (1 << 10)
@@ -38,17 +43,17 @@ #define RANGES_PER_FIXED_MTRR 8 #define NUM_FIXED_RANGES (NUM_FIXED_MTRRS * RANGES_PER_FIXED_MTRR)
-#define MTRR_FIX_64K_00000_MSR 0x250 -#define MTRR_FIX_16K_80000_MSR 0x258 -#define MTRR_FIX_16K_A0000_MSR 0x259 -#define MTRR_FIX_4K_C0000_MSR 0x268 -#define MTRR_FIX_4K_C8000_MSR 0x269 -#define MTRR_FIX_4K_D0000_MSR 0x26a -#define MTRR_FIX_4K_D8000_MSR 0x26b -#define MTRR_FIX_4K_E0000_MSR 0x26c -#define MTRR_FIX_4K_E8000_MSR 0x26d -#define MTRR_FIX_4K_F0000_MSR 0x26e -#define MTRR_FIX_4K_F8000_MSR 0x26f +#define MTRR_FIX_64K_00000_MSR 0x250 +#define MTRR_FIX_16K_80000_MSR 0x258 +#define MTRR_FIX_16K_A0000_MSR 0x259 +#define MTRR_FIX_4K_C0000_MSR 0x268 +#define MTRR_FIX_4K_C8000_MSR 0x269 +#define MTRR_FIX_4K_D0000_MSR 0x26a +#define MTRR_FIX_4K_D8000_MSR 0x26b +#define MTRR_FIX_4K_E0000_MSR 0x26c +#define MTRR_FIX_4K_E8000_MSR 0x26d +#define MTRR_FIX_4K_F0000_MSR 0x26e +#define MTRR_FIX_4K_F8000_MSR 0x26f
#if !defined(__ASSEMBLER__)
-- 1.8.2.1
Regards, Simon

Hi Simon,
On Fri, Jul 10, 2015 at 8:55 PM, Simon Glass sjg@chromium.org wrote:
Hi Bin,
On 6 July 2015 at 02:31, Bin Meng bmeng.cn@gmail.com wrote:
We should setup fixed range MTRRs for some legacy regions like VGA RAM and PCI ROM areas as uncacheable. Note FSP may setup these to other cache settings, but we can override this in x86_cpu_init_f().
Signed-off-by: Bin Meng bmeng.cn@gmail.com Acked-by: Simon Glass sjg@chromium.org
Changes in v2: None
arch/x86/cpu/cpu.c | 22 ++++++++++++++++++++++ arch/x86/include/asm/mtrr.h | 27 ++++++++++++++++----------- 2 files changed, 38 insertions(+), 11 deletions(-)
diff --git a/arch/x86/cpu/cpu.c b/arch/x86/cpu/cpu.c index d108ee5..9afdafb 100644 --- a/arch/x86/cpu/cpu.c +++ b/arch/x86/cpu/cpu.c @@ -28,6 +28,8 @@ #include <asm/cpu.h> #include <asm/lapic.h> #include <asm/mp.h> +#include <asm/msr.h> +#include <asm/mtrr.h> #include <asm/post.h> #include <asm/processor.h> #include <asm/processor-flags.h> @@ -352,6 +354,26 @@ int x86_cpu_init_f(void) gd->arch.has_mtrr = has_mtrr(); }
/* Configure fixed range MTRRs for some legacy regions */
if (gd->arch.has_mtrr) {
u64 mtrr_cap;
mtrr_cap = native_read_msr(MTRR_CAP_MSR);
if (mtrr_cap & MTRR_CAP_FIX) {
/* Mark the VGA RAM area as uncacheable */
native_write_msr(MTRR_FIX_16K_A0000_MSR, 0, 0);
/* Mark the PCI ROM area as uncacheable */
native_write_msr(MTRR_FIX_4K_C0000_MSR, 0, 0);
native_write_msr(MTRR_FIX_4K_C8000_MSR, 0, 0);
native_write_msr(MTRR_FIX_4K_D0000_MSR, 0, 0);
native_write_msr(MTRR_FIX_4K_D8000_MSR, 0, 0);
I just noticed that setting this up makes the Minnowmax ROM execution go really slowly. Do we need to turn off the cache? It goes from <1s to >4s.
Oops, that's bad. I guess we should turn on the cache for the rom execution then. BTW I found the tunnelcreek vbios changed the Cseg MTRR to write-through itself.
/* Enable the fixed range MTRRs */
msr_setbits_64(MTRR_DEF_TYPE_MSR, MTRR_DEF_TYPE_FIX_EN);
}
}
return 0;
}
[snip]
Regards, Bin

Hi Bin,
On 10 July 2015 at 09:39, Bin Meng bmeng.cn@gmail.com wrote:
Hi Simon,
On Fri, Jul 10, 2015 at 8:55 PM, Simon Glass sjg@chromium.org wrote:
Hi Bin,
On 6 July 2015 at 02:31, Bin Meng bmeng.cn@gmail.com wrote:
We should setup fixed range MTRRs for some legacy regions like VGA RAM and PCI ROM areas as uncacheable. Note FSP may setup these to other cache settings, but we can override this in x86_cpu_init_f().
Signed-off-by: Bin Meng bmeng.cn@gmail.com Acked-by: Simon Glass sjg@chromium.org
Changes in v2: None
arch/x86/cpu/cpu.c | 22 ++++++++++++++++++++++ arch/x86/include/asm/mtrr.h | 27 ++++++++++++++++----------- 2 files changed, 38 insertions(+), 11 deletions(-)
diff --git a/arch/x86/cpu/cpu.c b/arch/x86/cpu/cpu.c index d108ee5..9afdafb 100644 --- a/arch/x86/cpu/cpu.c +++ b/arch/x86/cpu/cpu.c @@ -28,6 +28,8 @@ #include <asm/cpu.h> #include <asm/lapic.h> #include <asm/mp.h> +#include <asm/msr.h> +#include <asm/mtrr.h> #include <asm/post.h> #include <asm/processor.h> #include <asm/processor-flags.h> @@ -352,6 +354,26 @@ int x86_cpu_init_f(void) gd->arch.has_mtrr = has_mtrr(); }
/* Configure fixed range MTRRs for some legacy regions */
if (gd->arch.has_mtrr) {
u64 mtrr_cap;
mtrr_cap = native_read_msr(MTRR_CAP_MSR);
if (mtrr_cap & MTRR_CAP_FIX) {
/* Mark the VGA RAM area as uncacheable */
native_write_msr(MTRR_FIX_16K_A0000_MSR, 0, 0);
/* Mark the PCI ROM area as uncacheable */
native_write_msr(MTRR_FIX_4K_C0000_MSR, 0, 0);
native_write_msr(MTRR_FIX_4K_C8000_MSR, 0, 0);
native_write_msr(MTRR_FIX_4K_D0000_MSR, 0, 0);
native_write_msr(MTRR_FIX_4K_D8000_MSR, 0, 0);
I just noticed that setting this up makes the Minnowmax ROM execution go really slowly. Do we need to turn off the cache? It goes from <1s to >4s.
Oops, that's bad. I guess we should turn on the cache for the rom execution then. BTW I found the tunnelcreek vbios changed the Cseg MTRR to write-through itself.
OK - can you try to do a patch for that? But first, why do we need to make the area uncacheable?
Regards, Simon

Hi Simon,
On Sat, Jul 11, 2015 at 12:09 AM, Simon Glass sjg@chromium.org wrote:
Hi Bin,
On 10 July 2015 at 09:39, Bin Meng bmeng.cn@gmail.com wrote:
Hi Simon,
On Fri, Jul 10, 2015 at 8:55 PM, Simon Glass sjg@chromium.org wrote:
Hi Bin,
On 6 July 2015 at 02:31, Bin Meng bmeng.cn@gmail.com wrote:
We should setup fixed range MTRRs for some legacy regions like VGA RAM and PCI ROM areas as uncacheable. Note FSP may setup these to other cache settings, but we can override this in x86_cpu_init_f().
Signed-off-by: Bin Meng bmeng.cn@gmail.com Acked-by: Simon Glass sjg@chromium.org
Changes in v2: None
arch/x86/cpu/cpu.c | 22 ++++++++++++++++++++++ arch/x86/include/asm/mtrr.h | 27 ++++++++++++++++----------- 2 files changed, 38 insertions(+), 11 deletions(-)
diff --git a/arch/x86/cpu/cpu.c b/arch/x86/cpu/cpu.c index d108ee5..9afdafb 100644 --- a/arch/x86/cpu/cpu.c +++ b/arch/x86/cpu/cpu.c @@ -28,6 +28,8 @@ #include <asm/cpu.h> #include <asm/lapic.h> #include <asm/mp.h> +#include <asm/msr.h> +#include <asm/mtrr.h> #include <asm/post.h> #include <asm/processor.h> #include <asm/processor-flags.h> @@ -352,6 +354,26 @@ int x86_cpu_init_f(void) gd->arch.has_mtrr = has_mtrr(); }
/* Configure fixed range MTRRs for some legacy regions */
if (gd->arch.has_mtrr) {
u64 mtrr_cap;
mtrr_cap = native_read_msr(MTRR_CAP_MSR);
if (mtrr_cap & MTRR_CAP_FIX) {
/* Mark the VGA RAM area as uncacheable */
native_write_msr(MTRR_FIX_16K_A0000_MSR, 0, 0);
/* Mark the PCI ROM area as uncacheable */
native_write_msr(MTRR_FIX_4K_C0000_MSR, 0, 0);
native_write_msr(MTRR_FIX_4K_C8000_MSR, 0, 0);
native_write_msr(MTRR_FIX_4K_D0000_MSR, 0, 0);
native_write_msr(MTRR_FIX_4K_D8000_MSR, 0, 0);
I just noticed that setting this up makes the Minnowmax ROM execution go really slowly. Do we need to turn off the cache? It goes from <1s to >4s.
Oops, that's bad. I guess we should turn on the cache for the rom execution then. BTW I found the tunnelcreek vbios changed the Cseg MTRR to write-through itself.
OK - can you try to do a patch for that? But first, why do we need to make the area uncacheable?
Yep, I can prepare a patch. I was referring to several chipset datasheet before, which mentions the suggested MTRR settings to UC, but this seems wrong.
Regards, Bin
participants (2)
-
Bin Meng
-
Simon Glass