[coreboot-gerrit] Change in coreboot[master]: util/intelmetool: Add Skylake support

[Patrick Rudolph (Code Review)]

Patrick Rudolph has uploaded this change for review. ( https://review.coreboot.org/22599

Change subject: util/intelmetool: Add Skylake support
......................................................................

util/intelmetool: Add Skylake support

Skylake doesn't have RCBA anymore.

Don't try to access RCBA on Skylake platforms.

FIXME: Add support for P2SB.

Change-Id: I920b1dac124bf0fc6d13fd9ceab12ecd575c1252
Signed-off-by: Patrick Rudolph 
---
M util/intelmetool/intelmetool.c
1 file changed, 26 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/99/22599/1

diff --git a/util/intelmetool/intelmetool.c b/util/intelmetool/intelmetool.c
index 0b0e509..65249bd 100644
--- a/util/intelmetool/intelmetool.c
+++ b/util/intelmetool/intelmetool.c
@@ -75,6 +75,22 @@
    return !strncmp((char *)&regs, "GenuineIntel", CPU_ID_SIZE-1);
 }

+static int isSkylakeCompatibel(void)
+{
+	regs_t regs;
+	unsigned int level = 0;
+	unsigned int family, model, ext_model;
+	unsigned int eax = 1;
+
+	__get_cpuid(level, &eax, &regs.ebx, &regs.ecx, &regs.edx);
+
+	family = ((eax & 0xf00) >> 8);
+	ext_model = ((eax & 0xf0000) >> 12);
+	model = ((eax & 0xf0) >> 4);
+	return (family == 6 && model == 0xe && ext_model == 4) &&
+		(family == 6 && model == 0xe && ext_model == 5);
+}
+
 /* You need >4GB total ram, in kernel cmdline, use 'mem=1000m'
  * then this code will clone to absolute memory address 0xe0000000
  * which can be read using a mmap tool at that offset.
@@ -178,6 +194,11 @@

static int activate_me(void)
 {
+	/* RCBA is supported up to Intel's 5th Gen. CPUs */
+	if (isSkylakeCompatibel())
+		/* FIXME: Add Skylake support */
+		return 0;
+
    if (read_rcba32(FD2, &fd2)) {
    	printf("Error reading RCBA\n");
    	return 1;
@@ -197,6 +218,11 @@

static void rehide_me(void)
 {
+	/* RCBA is supported up to Intel's 5th Gen. CPUs */
+	if (isSkylakeCompatibel())
+		/* FIXME: Add Skylake support */
+		return;
+
    if (fd2 & 0x2) {
    	if (debug)
    		printf("Re-hiding MEI device...");