soc/intel/broadwell: implement spi_flash_ctrlr_protect_region()

Implement the spi controller flash_protect() callback. No need to
have a global spi_flash_protect() once implemented.

BUG=b:69614064

Change-Id: I83f4310d8f78ba64727ba75eb75708d0cbaa7d53
Signed-off-by: Aaron Durbn <adurbin@chromium.org>
Reviewed-on: https://review.coreboot.org/22882
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>

src/soc/intel/broadwell/include/soc/spi.h

@@ -101,6 +101,4 @@
 #define  SPIBAR_SSFC_DATA           (1 << 14)
 #define  SPIBAR_SSFC_GO             (1 << 1)
 
-int spi_flash_protect(u32 start, u32 size);
-
 #endif

src/soc/intel/broadwell/spi.c

@@ -612,9 +612,11 @@ static int spi_ctrlr_xfer(const struct spi_slave *slave, const void *dout,
 }
 
 /* Use first empty Protected Range Register to cover region of flash */
-int spi_flash_protect(u32 start, u32 size)
+static int spi_flash_protect(const struct spi_flash *flash,
+				const struct region *region)
 {
-	u32 end = start + size - 1;
+	u32 start = region_offset(region);
+	u32 end = start + region_sz(region) - 1;
 	u32 reg;
 	int prr;
 
@@ -652,6 +654,7 @@ static const struct spi_ctrlr spi_ctrlr = {
 	.xfer = spi_ctrlr_xfer,
 	.xfer_vector = spi_xfer_two_vectors,
 	.max_xfer_size = member_size(ich9_spi_regs, fdata),
+	.flash_protect = spi_flash_protect,
 };
 
 const struct spi_ctrlr_buses spi_ctrlr_bus_map[] = {