3 files changed, 93 insertions, 0 deletions
diff --git a/src/soc/intel/common/block/gpmr/Kconfig b/src/soc/intel/common/block/gpmr/Kconfig
new file mode 100644
index 0000000000..2cc4646312
--- /dev/null
+++ b/src/soc/intel/common/block/gpmr/Kconfig
@@ -0,0 +1,5 @@
+config SOC_INTEL_COMMON_BLOCK_DMI
+	bool
+	select SOC_INTEL_COMMON_BLOCK_PCR
+	help
+	  Intel Processor common DMI support
diff --git a/src/soc/intel/common/block/gpmr/Makefile.inc b/src/soc/intel/common/block/gpmr/Makefile.inc
new file mode 100644
index 0000000000..0abf61fda5
--- /dev/null
+++ b/src/soc/intel/common/block/gpmr/Makefile.inc
@@ -0,0 +1,7 @@
+ifeq ($(CONFIG_SOC_INTEL_COMMON_BLOCK_DMI), y)
+
+bootblock-y += gpmr.c
+romstage-y += gpmr.c
+ramstage-y += gpmr.c
+
+endif
diff --git a/src/soc/intel/common/block/gpmr/gpmr.c b/src/soc/intel/common/block/gpmr/gpmr.c
new file mode 100644
index 0000000000..1a3a6023d6
--- /dev/null
+++ b/src/soc/intel/common/block/gpmr/gpmr.c
@@ -0,0 +1,81 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <console/console.h>
+#include <intelblocks/dmi.h>
+#include <intelblocks/pcr.h>
+#include <soc/pcr_ids.h>
+
+#define MAX_GPMR_REGS				3
+
+#define GPMR_OFFSET(x)				(0x277c + (x) * 8)
+#define  DMI_PCR_GPMR_LIMIT_MASK		0xffff0000
+#define  DMI_PCR_GPMR_BASE_SHIFT		16
+#define  DMI_PCR_GPMR_BASE_MASK			0xffff
+
+#define GPMR_DID_OFFSET(x)			(0x2780 + (x) * 8)
+#define  DMI_PCR_GPMR_EN			BIT(31)
+
+/* GPMR Register read given offset */
+static uint32_t gpmr_read32(uint16_t offset)
+{
+	return pcr_read32(PID_DMI, offset);
+}
+
+/* GPMR Register write given offset and val */
+static void gpmr_write32(uint16_t offset, uint32_t val)
+{
+	return pcr_write32(PID_DMI, offset, val);
+}
+
+/* Check for available free gpmr */
+static int get_available_gpmr(void)
+{
+	int i;
+	uint32_t val;
+
+	for (i = 0; i < MAX_GPMR_REGS; i++) {
+		val = gpmr_read32(GPMR_DID_OFFSET(i));
+		if (!(val & DMI_PCR_GPMR_EN))
+			return i;
+	}
+	printk(BIOS_ERR, "%s: No available free gpmr found\n", __func__);
+	return CB_ERR;
+}
+
+/* Configure GPMR for the given base and size of extended BIOS Region */
+enum cb_err dmi_enable_gpmr(uint32_t base, uint32_t size, uint32_t dest_id)
+{
+	int gpmr_num;
+	uint32_t limit;
+
+	if (base & ~(DMI_PCR_GPMR_BASE_MASK << DMI_PCR_GPMR_BASE_SHIFT)) {
+		printk(BIOS_ERR, "base is not 64-KiB aligned!\n");
+		return CB_ERR;
+	}
+
+	limit = base + (size - 1);
+
+	if (limit < base) {
+		printk(BIOS_ERR, "Invalid limit: limit cannot be less than base!\n");
+		return CB_ERR;
+	}
+
+	if ((limit & ~DMI_PCR_GPMR_LIMIT_MASK) != 0xffff) {
+		printk(BIOS_ERR, "limit does not end on a 64-KiB boundary!\n");
+		return CB_ERR;
+	}
+
+	/* Get available free GPMR */
+	gpmr_num = get_available_gpmr();
+	if (gpmr_num == CB_ERR)
+		return CB_ERR;
+
+	/* Program Range for the given decode window */
+	gpmr_write32(GPMR_OFFSET(gpmr_num), (limit & DMI_PCR_GPMR_LIMIT_MASK) |
+		((base >> DMI_PCR_GPMR_BASE_SHIFT) & DMI_PCR_GPMR_BASE_MASK));
+
+	/* Program source decode enable bit and the Destination ID */
+	gpmr_write32(GPMR_DID_OFFSET(gpmr_num), dest_id | DMI_PCR_GPMR_EN);
+
+	return CB_SUCCESS;
+}