[U-Boot] [PATCH 01/10] x86: Change pci option rom area MTRR setting to cacheable

[Bin Meng]

Turn on cache on the pci option rom area to improve the performance.

Signed-off-by: Bin Meng <bmeng.cn at gmail.com>
---

 arch/x86/cpu/cpu.c          | 27 ++++++++++++++++++++-------
 arch/x86/include/asm/mtrr.h |  2 ++
 2 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/arch/x86/cpu/cpu.c b/arch/x86/cpu/cpu.c
index af927b9..b4e0fd9 100644
--- a/arch/x86/cpu/cpu.c
+++ b/arch/x86/cpu/cpu.c
@@ -363,13 +363,26 @@ int x86_cpu_init_f(void)
 		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);
+			native_write_msr(MTRR_FIX_16K_A0000_MSR,
+					 MTRR_FIX_TYPE(MTRR_TYPE_UNCACHEABLE),
+					 MTRR_FIX_TYPE(MTRR_TYPE_UNCACHEABLE));
+
+			/*
+			 * Mark the PCI ROM area as cacheable to improve ROM
+			 * execution performance.
+			 */
+			native_write_msr(MTRR_FIX_4K_C0000_MSR,
+					 MTRR_FIX_TYPE(MTRR_TYPE_WRBACK),
+					 MTRR_FIX_TYPE(MTRR_TYPE_WRBACK));
+			native_write_msr(MTRR_FIX_4K_C8000_MSR,
+					 MTRR_FIX_TYPE(MTRR_TYPE_WRBACK),
+					 MTRR_FIX_TYPE(MTRR_TYPE_WRBACK));
+			native_write_msr(MTRR_FIX_4K_D0000_MSR,
+					 MTRR_FIX_TYPE(MTRR_TYPE_WRBACK),
+					 MTRR_FIX_TYPE(MTRR_TYPE_WRBACK));
+			native_write_msr(MTRR_FIX_4K_D8000_MSR,
+					 MTRR_FIX_TYPE(MTRR_TYPE_WRBACK),
+					 MTRR_FIX_TYPE(MTRR_TYPE_WRBACK));
 
 			/* Enable the fixed range MTRRs */
 			msr_setbits_64(MTRR_DEF_TYPE_MSR, MTRR_DEF_TYPE_FIX_EN);
diff --git a/arch/x86/include/asm/mtrr.h b/arch/x86/include/asm/mtrr.h
index 70762ee..f9b30f6 100644
--- a/arch/x86/include/asm/mtrr.h
+++ b/arch/x86/include/asm/mtrr.h
@@ -55,6 +55,8 @@
 #define MTRR_FIX_4K_F0000_MSR	0x26e
 #define MTRR_FIX_4K_F8000_MSR	0x26f
 
+#define MTRR_FIX_TYPE(t)	((t << 24) | (t << 16) | (t << 8) | t)
+
 #if !defined(__ASSEMBLER__)
 
 /**
-- 
1.8.2.1