Fix incorrect valid and writable flash flags

The valid and writable flags the EC sends back to the AP are incorrect.
They are a little bit different on differnt chips, so let's move it to
flash physical layer. This is not any causing problem, but we should fix
this.

BUG=chrome-os-partner:32745
TEST=make buildall
BRANCH=samus

Change-Id: Ibcda5ae770f5ea02cde094490997a5bc447df88f
Signed-off-by: Vic Yang <victoryang@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/222661
Reviewed-by: Randall Spangler <rspangler@chromium.org>

7 files changed, 149 insertions, 17 deletions

diff --git a/chip/host/flash.c b/chip/host/flash.c
index 892e4067a9..2be40b37df 100644
--- a/chip/host/flash.c
+++ b/chip/host/flash.c
@@ -118,6 +118,32 @@ int flash_physical_protect_now(int all)
 	return EC_SUCCESS;
 }
 
+uint32_t flash_physical_get_valid_flags(void)
+{
+	return EC_FLASH_PROTECT_RO_AT_BOOT |
+	       EC_FLASH_PROTECT_RO_NOW |
+	       EC_FLASH_PROTECT_ALL_NOW;
+}
+
+uint32_t flash_physical_get_writable_flags(uint32_t cur_flags)
+{
+	uint32_t ret = 0;
+
+	/* If RO protection isn't enabled, its at-boot state can be changed. */
+	if (!(cur_flags & EC_FLASH_PROTECT_RO_NOW))
+		ret |= EC_FLASH_PROTECT_RO_AT_BOOT;
+
+	/*
+	 * If entire flash isn't protected at this boot, it can be enabled if
+	 * the WP GPIO is asserted.
+	 */
+	if (!(cur_flags & EC_FLASH_PROTECT_ALL_NOW) &&
+	    (cur_flags & EC_FLASH_PROTECT_GPIO_ASSERTED))
+		ret |= EC_FLASH_PROTECT_ALL_NOW;
+
+	return ret;
+}
+
 int flash_pre_init(void)
 {
 	uint32_t prot_flags;
diff --git a/chip/lm4/flash.c b/chip/lm4/flash.c
index c6b676d87b..dd9474f51d 100644
--- a/chip/lm4/flash.c
+++ b/chip/lm4/flash.c
@@ -204,6 +204,32 @@ int flash_physical_protect_now(int all)
 	return EC_SUCCESS;
 }
 
+uint32_t flash_physical_get_valid_flags(void)
+{
+	return EC_FLASH_PROTECT_RO_AT_BOOT |
+	       EC_FLASH_PROTECT_RO_NOW |
+	       EC_FLASH_PROTECT_ALL_NOW;
+}
+
+uint32_t flash_physical_get_writable_flags(uint32_t cur_flags)
+{
+	uint32_t ret = 0;
+
+	/* If RO protection isn't enabled, its at-boot state can be changed. */
+	if (!(cur_flags & EC_FLASH_PROTECT_RO_NOW))
+		ret |= EC_FLASH_PROTECT_RO_AT_BOOT;
+
+	/*
+	 * If entire flash isn't protected at this boot, it can be enabled if
+	 * the WP GPIO is asserted.
+	 */
+	if (!(cur_flags & EC_FLASH_PROTECT_ALL_NOW) &&
+	    (cur_flags & EC_FLASH_PROTECT_GPIO_ASSERTED))
+		ret |= EC_FLASH_PROTECT_ALL_NOW;
+
+	return ret;
+}
+
 
 /*****************************************************************************/
 /* High-level APIs */
diff --git a/chip/stm32/flash-stm32f.c b/chip/stm32/flash-stm32f.c
index 68e6b7a8e6..299d40d5c1 100644
--- a/chip/stm32/flash-stm32f.c
+++ b/chip/stm32/flash-stm32f.c
@@ -67,6 +67,32 @@ int flash_physical_protect_now(int all)
 	}
 }
 
+uint32_t flash_physical_get_valid_flags(void)
+{
+	return EC_FLASH_PROTECT_RO_AT_BOOT |
+	       EC_FLASH_PROTECT_RO_NOW |
+	       EC_FLASH_PROTECT_ALL_NOW;
+}
+
+uint32_t flash_physical_get_writable_flags(uint32_t cur_flags)
+{
+	uint32_t ret = 0;
+
+	/* If RO protection isn't enabled, its at-boot state can be changed. */
+	if (!(cur_flags & EC_FLASH_PROTECT_RO_NOW))
+		ret |= EC_FLASH_PROTECT_RO_AT_BOOT;
+
+	/*
+	 * If entire flash isn't protected at this boot, it can be enabled if
+	 * the WP GPIO is asserted.
+	 */
+	if (!(cur_flags & EC_FLASH_PROTECT_ALL_NOW) &&
+	    (cur_flags & EC_FLASH_PROTECT_GPIO_ASSERTED))
+		ret |= EC_FLASH_PROTECT_ALL_NOW;
+
+	return ret;
+}
+
 int flash_physical_restore_state(void)
 {
 	uint32_t reset_flags = system_get_reset_flags();
diff --git a/chip/stm32/flash-stm32f0.c b/chip/stm32/flash-stm32f0.c
index bbf3574c21..85e65c6ac4 100644
--- a/chip/stm32/flash-stm32f0.c
+++ b/chip/stm32/flash-stm32f0.c
@@ -42,3 +42,30 @@ int flash_physical_restore_state(void)
 	/* Nothing to restore */
 	return 0;
 }
+
+uint32_t flash_physical_get_valid_flags(void)
+{
+	return EC_FLASH_PROTECT_RO_AT_BOOT |
+	       EC_FLASH_PROTECT_ALL_AT_BOOT |
+	       EC_FLASH_PROTECT_RO_NOW |
+	       EC_FLASH_PROTECT_ALL_NOW;
+}
+
+uint32_t flash_physical_get_writable_flags(uint32_t cur_flags)
+{
+	uint32_t ret = 0;
+
+	/* If RO protection isn't enabled, its at-boot state can be changed. */
+	if (!(cur_flags & EC_FLASH_PROTECT_RO_NOW))
+		ret |= EC_FLASH_PROTECT_RO_AT_BOOT;
+
+	/*
+	 * RW at-boot state can be set if WP GPIO is asserted and can always
+	 * be cleared.
+	 */
+	if (cur_flags & (EC_FLASH_PROTECT_ALL_AT_BOOT |
+			 EC_FLASH_PROTECT_GPIO_ASSERTED))
+		ret |= EC_FLASH_PROTECT_ALL_AT_BOOT;
+
+	return ret;
+}
diff --git a/chip/stm32/flash-stm32l.c b/chip/stm32/flash-stm32l.c
index 98f46565a3..106e436c80 100644
--- a/chip/stm32/flash-stm32l.c
+++ b/chip/stm32/flash-stm32l.c
@@ -400,6 +400,32 @@ int flash_physical_protect_now(int all)
 	}
 }
 
+uint32_t flash_physical_get_valid_flags(void)
+{
+	return EC_FLASH_PROTECT_RO_AT_BOOT |
+	       EC_FLASH_PROTECT_RO_NOW |
+	       EC_FLASH_PROTECT_ALL_NOW;
+}
+
+uint32_t flash_physical_get_writable_flags(uint32_t cur_flags)
+{
+	uint32_t ret = 0;
+
+	/* If RO protection isn't enabled, its at-boot state can be changed. */
+	if (!(cur_flags & EC_FLASH_PROTECT_RO_NOW))
+		ret |= EC_FLASH_PROTECT_RO_AT_BOOT;
+
+	/*
+	 * If entire flash isn't protected at this boot, it can be enabled if
+	 * the WP GPIO is asserted.
+	 */
+	if (!(cur_flags & EC_FLASH_PROTECT_ALL_NOW) &&
+	    (cur_flags & EC_FLASH_PROTECT_GPIO_ASSERTED))
+		ret |= EC_FLASH_PROTECT_ALL_NOW;
+
+	return ret;
+}
+
 int flash_pre_init(void)
 {
 	uint32_t reset_flags = system_get_reset_flags();
diff --git a/common/flash.c b/common/flash.c
index 15af5cd1e8..b6001751d5 100644
--- a/common/flash.c
+++ b/common/flash.c
@@ -624,23 +624,9 @@ static int flash_command_protect(struct host_cmd_handler_args *args)
 	r->valid_flags =
 		EC_FLASH_PROTECT_GPIO_ASSERTED |
 		EC_FLASH_PROTECT_ERROR_STUCK |
-		EC_FLASH_PROTECT_RO_AT_BOOT |
-		EC_FLASH_PROTECT_RO_NOW |
-		EC_FLASH_PROTECT_ALL_NOW |
-		EC_FLASH_PROTECT_ERROR_INCONSISTENT;
-	r->writable_flags = 0;
-
-	/* If RO protection isn't enabled, its at-boot state can be changed. */
-	if (!(r->flags & EC_FLASH_PROTECT_RO_NOW))
-		r->writable_flags |= EC_FLASH_PROTECT_RO_AT_BOOT;
-
-	/*
-	 * If entire flash isn't protected at this boot, it can be enabled if
-	 * the WP GPIO is asserted.
-	 */
-	if (!(r->flags & EC_FLASH_PROTECT_ALL_NOW) &&
-	    (r->flags & EC_FLASH_PROTECT_GPIO_ASSERTED))
-		r->writable_flags |= EC_FLASH_PROTECT_ALL_NOW;
+		EC_FLASH_PROTECT_ERROR_INCONSISTENT |
+		flash_physical_get_valid_flags();
+	r->writable_flags = flash_physical_get_writable_flags(r->flags);
 
 	args->response_size = sizeof(*r);
 
diff --git a/include/flash.h b/include/flash.h
index 0c6e11c429..a77d5a1cb2 100644
--- a/include/flash.h
+++ b/include/flash.h
@@ -110,6 +110,21 @@ int flash_physical_force_reload(void);
  */
 int flash_physical_restore_state(void);
 
+/**
+ * Return the valid flash protect flags.
+ *
+ * @return a combination of EC_FLASH_PROTECT_* flags from ec_commands.h
+ */
+uint32_t flash_physical_get_valid_flags(void);
+
+/**
+ * Return the writable flash protect flags.
+ *
+ * @param cur_flags The current flash protect flags.
+ * @return a combination of EC_FLASH_PROTECT_* flags from ec_commands.h
+ */
+uint32_t flash_physical_get_writable_flags(uint32_t cur_flags);
+
 /*****************************************************************************/
 /* Low-level common code for use by flash modules. */