3 files changed, 50 insertions, 0 deletions
diff --git a/src/soc/intel/broadwell/Kconfig b/src/soc/intel/broadwell/Kconfig
index 2e70f45eea..e14476abbd 100644
--- a/src/soc/intel/broadwell/Kconfig
+++ b/src/soc/intel/broadwell/Kconfig
@@ -16,6 +16,7 @@ config CPU_SPECIFIC_OPTIONS
 	select BACKUP_DEFAULT_SMM_REGION
 	select CACHE_MRC_BIN
 	select CACHE_MRC_SETTINGS
+	select MRC_SETTINGS_PROTECT
 	select CACHE_RELOCATED_RAMSTAGE_OUTSIDE_CBMEM
 	select CACHE_ROM
 	select CAR_MIGRATION
diff --git a/src/soc/intel/broadwell/include/soc/spi.h b/src/soc/intel/broadwell/include/soc/spi.h
index 8b95f70a5f..1449e29cda 100644
--- a/src/soc/intel/broadwell/include/soc/spi.h
+++ b/src/soc/intel/broadwell/include/soc/spi.h
@@ -35,6 +35,14 @@
 #define SPIBAR_FDOC		0xb0
 #define SPIBAR_FDOD		0xb4
 
+#define SPI_PRR_MAX		5
+#define SPI_PRR(x)		(0x74 + ((x) * 4))
+#define SPI_PRR_SHIFT		12
+#define SPI_PRR_MASK		0x1fff
+#define SPI_PRR_BASE_SHIFT	0
+#define SPI_PRR_LIMIT_SHIFT	16
+#define SPI_PRR_WPE		(1 << 31)
+
 #define SPIBAR_PREOP		0x94
 #define SPIBAR_OPTYPE		0x96
 #define SPIBAR_OPMENU_LOWER	0x98
@@ -97,4 +105,6 @@
 #define  SPIBAR_SSFC_DATA           (1 << 14)
 #define  SPIBAR_SSFC_GO             (1 << 1)
 
+int spi_flash_protect(u32 start, u32 size);
+
 #endif
diff --git a/src/soc/intel/broadwell/spi.c b/src/soc/intel/broadwell/spi.c
index 6d2f103d8a..0fca05951b 100644
--- a/src/soc/intel/broadwell/spi.c
+++ b/src/soc/intel/broadwell/spi.c
@@ -29,6 +29,8 @@
 #include <device/pci_ids.h>
 #include <spi-generic.h>
 #include <soc/pci_devs.h>
+#include <soc/rcba.h>
+#include <soc/spi.h>
 
 #ifdef __SMM__
 #define pci_read_config_byte(dev, reg, targ)\
@@ -637,3 +639,40 @@ int spi_xfer(struct spi_slave *slave, const void *dout,
 
 	return 0;
 }
+
+/* Use first empty Protected Range Register to cover region of flash */
+int spi_flash_protect(u32 start, u32 size)
+{
+	u32 end = start + size - 1;
+	u32 reg;
+	int prr;
+
+	/* Find first empty PRR */
+	for (prr = 0; prr < SPI_PRR_MAX; prr++) {
+		reg = SPIBAR32(SPI_PRR(prr));
+		if (reg == 0)
+			break;
+	}
+	if (prr >= SPI_PRR_MAX) {
+		printk(BIOS_ERR, "ERROR: No SPI PRR free!\n");
+		return -1;
+	}
+
+	/* Set protected range base and limit */
+	reg = ((end >> SPI_PRR_SHIFT) & SPI_PRR_MASK);
+	reg <<= SPI_PRR_LIMIT_SHIFT;
+	reg |= ((start >> SPI_PRR_SHIFT) & SPI_PRR_MASK);
+	reg |= SPI_PRR_WPE;
+
+	/* Set the PRR register and verify it is protected */
+	SPIBAR32(SPI_PRR(prr)) = reg;
+	reg = SPIBAR32(SPI_PRR(prr));
+	if (!(reg & SPI_PRR_WPE)) {
+		printk(BIOS_ERR, "ERROR: Unable to set SPI PRR %d\n", prr);
+		return -1;
+	}
+
+	printk(BIOS_INFO, "%s: PRR %d is enabled for range 0x%08x-0x%08x\n",
+	       __func__, prr, start, end);
+	return 0;
+}