flash: Pass more precise parameter to flash_[physical_]protect_at_boot

In preparation for adding the rollback protection block, pass
EC_FLASH_PROTECT_RO/ALL_AT_BOOT to flash_[physical_]protect_at_boot,
instead of an enumeration no protection/RO/ALL.

This will later allow us to protect/unprotect the rollback region only,
by adding a EC_FLASH_PROTECT_ROLLBACK_AT_BOOT flag.

BRANCH=none
BUG=chrome-os-partner:61671
TEST=Build hammer with CONFIG_CMD_FLASH command, so that write protection
     can be checked with flasherase/flashwrite.
TEST=On hammer (stm32f072):
     flashinfo => RO+RW not protected
     flashwp true; reboot => only RO protected
     flashwp rw; reboot => RO+RW protected
     flashwp norw; reboot => only RO protected
TEST=On reef (npcx):
     deassert WP, flashwp false; flashinfo => RO+RW not protected
     flashwp true => only RO protected
     reboot => only RO protected
     flashwp rw => RO+RW protected
     reboot => only RO protected

Change-Id: Iec96a7377baabc9100fc59de0a31505095a3499f
Reviewed-on: https://chromium-review.googlesource.com/430518
Commit-Ready: Nicolas Boichat <drinkcat@chromium.org>
Tested-by: Nicolas Boichat <drinkcat@chromium.org>
Reviewed-by: Randall Spangler <rspangler@chromium.org>

3 files changed, 16 insertions, 18 deletions

diff --git a/chip/stm32/flash-f.c b/chip/stm32/flash-f.c
index 09a52ded2e..0c99ec398d 100644
--- a/chip/stm32/flash-f.c
+++ b/chip/stm32/flash-f.c
@@ -338,12 +338,11 @@ static int flash_physical_get_protect_at_boot(int block)
 	return (!(val & (1 << (block % 8)))) ? 1 : 0;
 }
 
-int flash_physical_protect_at_boot(enum flash_wp_range range)
+int flash_physical_protect_at_boot(uint32_t new_flags)
 {
 	int block;
 	int i;
 	int original_val[4], val[4];
-	enum flash_wp_range cur_range;
 
 	for (i = 0; i < 4; ++i)
 		original_val[i] = val[i] = read_optb(i * 2 + 8);
@@ -351,14 +350,14 @@ int flash_physical_protect_at_boot(enum flash_wp_range range)
 	for (block = WP_BANK_OFFSET;
 	     block < WP_BANK_OFFSET + PHYSICAL_BANKS;
 	     block++) {
+		int protect = new_flags & EC_FLASH_PROTECT_ALL_AT_BOOT;
 		int byte_off = STM32_OPTB_WRP_OFF(block/8) / 2 - 4;
 
-		if (block >= WP_BANK_OFFSET + WP_BANK_COUNT)
-			cur_range = FLASH_WP_ALL;
-		else
-			cur_range = FLASH_WP_RO;
+		if (block >= WP_BANK_OFFSET &&
+		    block < WP_BANK_OFFSET + WP_BANK_COUNT)
+			protect |= new_flags & EC_FLASH_PROTECT_RO_AT_BOOT;
 
-		if (cur_range <= range)
+		if (protect)
 			val[byte_off] = val[byte_off] & (~(1 << (block % 8)));
 		else
 			val[byte_off] = val[byte_off] | (1 << (block % 8));
@@ -434,7 +433,8 @@ int flash_pre_init(void)
 			 * update to the write protect register and reboot so
 			 * it takes effect.
 			 */
-			flash_physical_protect_at_boot(FLASH_WP_RO);
+			flash_physical_protect_at_boot(
+				EC_FLASH_PROTECT_RO_AT_BOOT);
 			need_reset = 1;
 		}
 
@@ -448,8 +448,7 @@ int flash_pre_init(void)
 			 * go away.
 			 */
 			flash_protect_at_boot(
-				(prot_flags & EC_FLASH_PROTECT_RO_AT_BOOT) ?
-				FLASH_WP_RO : FLASH_WP_NONE);
+				prot_flags & EC_FLASH_PROTECT_RO_AT_BOOT);
 			need_reset = 1;
 		}
 	} else {
diff --git a/chip/stm32/flash-stm32f4.c b/chip/stm32/flash-stm32f4.c
index 48815d6956..6b6b64f73a 100644
--- a/chip/stm32/flash-stm32f4.c
+++ b/chip/stm32/flash-stm32f4.c
@@ -196,7 +196,7 @@ static void clear_flash_errors(void)
 /*****************************************************************************/
 /* Physical layer APIs */
 
-int flash_physical_protect_at_boot(enum flash_wp_range range)
+int flash_physical_protect_at_boot(uint32_t new_flags)
 {
 	return EC_SUCCESS;
 }
diff --git a/chip/stm32/flash-stm32l.c b/chip/stm32/flash-stm32l.c
index ce292bb58d..f796f4efaa 100644
--- a/chip/stm32/flash-stm32l.c
+++ b/chip/stm32/flash-stm32l.c
@@ -317,20 +317,20 @@ int flash_physical_get_protect(int block)
 	return STM32_FLASH_WRPR & (1 << block);
 }
 
-int flash_physical_protect_at_boot(enum flash_wp_range range)
+int flash_physical_protect_at_boot(uint32_t new_flags)
 {
 	uint32_t prot;
 	uint32_t mask = ((1 << WP_BANK_COUNT) - 1) << WP_BANK_OFFSET;
 	int rv;
 
-	if (range == FLASH_WP_ALL)
+	if (new_flags & EC_FLASH_PROTECT_ALL_AT_BOOT)
 		return EC_ERROR_UNIMPLEMENTED;
 
 	/* Read the current protection status */
 	prot = read_optb_wrp();
 
 	/* Set/clear bits */
-	if (range == FLASH_WP_RO)
+	if (new_flags & EC_FLASH_PROTECT_RO_AT_BOOT)
 		prot |= mask;
 	else
 		prot &= ~mask;
@@ -448,7 +448,7 @@ int flash_pre_init(void)
 			 * update to the write protect register and reboot so
 			 * it takes effect.
 			 */
-			flash_protect_at_boot(FLASH_WP_RO);
+			flash_protect_at_boot(EC_FLASH_PROTECT_RO_AT_BOOT);
 			need_reset = 1;
 		}
 
@@ -457,9 +457,8 @@ int flash_pre_init(void)
 			 * Write protect register was in an inconsistent state.
 			 * Set it back to a good state and reboot.
 			 */
-			flash_protect_at_boot(
-				(prot_flags & EC_FLASH_PROTECT_RO_AT_BOOT) ?
-				FLASH_WP_RO : FLASH_WP_NONE);
+			flash_protect_at_boot(prot_flags &
+					EC_FLASH_PROTECT_RO_AT_BOOT);
 			need_reset = 1;
 		}
 	} else if (prot_flags & (EC_FLASH_PROTECT_RO_NOW |