Patch set updated for coreboot: soc/intel/apollolake: Add cache for BIOS ROM

[Andrey Petrov]

Andrey Petrov ([e-mail]) just uploaded a new patch set to gerrit, which you can find at https://review.coreboot.org/14480

-gerrit

commit 30e88c7a14048e9b9f87c4237eba60013649e7d4
Author: Andrey Petrov 
Date:   Sat Apr 23 12:31:01 2016 -0700

soc/intel/apollolake: Add cache for BIOS ROM

Enable caching of BIOS region with variable MTRR. This is most
    useful if enabled early such as in bootblock.

Change-Id: I39f33ca43f06fce26d1d48e706c97f097e3c10f1
    Signed-off-by: Andrey Petrov 
---
 src/cpu/x86/mtrr/Makefile.inc                  |  1 +
 src/soc/intel/apollolake/bootblock/bootblock.c | 21 +++++++++++++++++++++
 2 files changed, 22 insertions(+)

diff --git a/src/cpu/x86/mtrr/Makefile.inc b/src/cpu/x86/mtrr/Makefile.inc
index 9b7207b..e6e9c50 100644
--- a/src/cpu/x86/mtrr/Makefile.inc
+++ b/src/cpu/x86/mtrr/Makefile.inc
@@ -1,2 +1,3 @@
 ramstage-y += mtrr.c
 romstage-y += earlymtrr.c
+bootblock-y += earlymtrr.c
diff --git a/src/soc/intel/apollolake/bootblock/bootblock.c b/src/soc/intel/apollolake/bootblock/bootblock.c
index bb3b9c1..2456455 100644
--- a/src/soc/intel/apollolake/bootblock/bootblock.c
+++ b/src/soc/intel/apollolake/bootblock/bootblock.c
@@ -16,7 +16,9 @@
  */
 #include <arch/cpu.h>
 #include <bootblock_common.h>
+#include <cpu/x86/mtrr.h>
 #include <device/pci.h>
+#include <lib.h>
 #include <soc/bootblock.h>
 #include <soc/cpu.h>
 #include <soc/gpio.h>
@@ -76,6 +78,24 @@ void asmlinkage bootblock_c_entry(void)
    main();
 }

+static void cache_bios_region(void)
+{
+	int mtrr;
+	uint32_t rom_size, alignment;
+
+	mtrr = get_free_var_mtrr();
+
+	if (mtrr==-1)
+		return;
+
+	/* Only the IFD BIOS region is memory mapped (at top of 4G) */
+	rom_size =  CONFIG_IFD_BIOS_END - CONFIG_IFD_BIOS_START;
+	/* Round to power of two */
+	alignment = 1 << (log2_ceil(rom_size));
+	rom_size = ALIGN_UP(rom_size, alignment);
+	set_var_mtrr(mtrr, 4ULL*GiB - rom_size, rom_size, MTRR_TYPE_WRPROT);
+}
+
 void bootblock_soc_early_init(void)
 {
    /* Prepare UART for serial console. */
@@ -88,4 +108,5 @@ void bootblock_soc_early_init(void)
    if (IS_ENABLED(CONFIG_EC_GOOGLE_CHROMEEC_LPC))
    	early_lpc_enable();

+	cache_bios_region();
 }