soc/intel/common: Add function to DLOCK PR registers

Add a function in FAST_SPI library to discrete lock the PR
registers 0 to 4.

BUG=none
BRANCH=none
TEST=Build and boot poppy

Change-Id: I46e1948315ea9489932efdf7d60d6d78ab3948a6
Signed-off-by: Barnali Sarkar <barnali.sarkar@intel.com>
Reviewed-on: https://review.coreboot.org/21063
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/soc/intel/common/block/fast_spi/fast_spi.c

@@ -152,6 +152,23 @@ void fast_spi_lock_bar(void)
 	write16(spibar + SPIBAR_HSFSTS_CTL, hsfs);
 }
 
+/*
+ * Set FAST_SPIBAR + DLOCK (0x0C) register bits to discrete lock the
+ * FAST_SPI Protected Range (PR) registers.
+ */
+void fast_spi_pr_dlock(void)
+{
+	void *spibar = fast_spi_get_bar();
+	uint32_t dlock;
+
+	dlock = read32(spibar + SPIBAR_DLOCK);
+	dlock |= (SPIBAR_DLOCK_PR0LOCKDN | SPIBAR_DLOCK_PR1LOCKDN
+			| SPIBAR_DLOCK_PR2LOCKDN | SPIBAR_DLOCK_PR3LOCKDN
+			| SPIBAR_DLOCK_PR4LOCKDN);
+
+	write32(spibar + SPIBAR_DLOCK, dlock);
+}
+
 /*
  * Set FAST_SPIBAR Soft Reset Data Register value.
  */

src/soc/intel/common/block/fast_spi/fast_spi_def.h

@@ -34,6 +34,7 @@
 #define SPIBAR_BFPREG			0x00
 #define SPIBAR_HSFSTS_CTL		0x04
 #define SPIBAR_FADDR			0x08
+#define SPIBAR_DLOCK			0x0c
 #define SPIBAR_FDATA(n)			(0x10 + ((n) & 0xf) * 4)
 #define SPIBAR_FPR_BASE			0x84
 #define SPIBAR_FPR(n)			0x84 + (4 * n))
@@ -87,6 +88,13 @@
 /* Bit definitions for FADDR (0x08) register */
 #define SPIBAR_FADDR_MASK		0x7FFFFFF
 
+/* Bit definitions for DLOCK (0x0C) register */
+#define SPIBAR_DLOCK_PR0LOCKDN		(1 << 8)
+#define SPIBAR_DLOCK_PR1LOCKDN		(1 << 9)
+#define SPIBAR_DLOCK_PR2LOCKDN		(1 << 10)
+#define SPIBAR_DLOCK_PR3LOCKDN		(1 << 11)
+#define SPIBAR_DLOCK_PR4LOCKDN		(1 << 12)
+
 /* Maximum bytes of data that can fit in FDATAn (0x10) registers */
 #define SPIBAR_FDATA_FIFO_SIZE		0x40
 

src/soc/intel/common/block/include/intelblocks/fast_spi.h

@@ -48,6 +48,11 @@ void fast_spi_set_opcode_menu(void);
  * Lock FAST_SPIBAR.
  */
 void fast_spi_lock_bar(void);
+/*
+ * Set FAST_SPIBAR + DLOCK (0x0C) register bits to discrete lock the
+ * FAST_SPI Protected Range (PR) registers.
+ */
+void fast_spi_pr_dlock(void);
 /*
  * Set FAST_SPIBAR Soft Reset Data Register value.
  */