diff options
| -rw-r--r-- | chip/stm32/system.c | 36 |
1 files changed, 28 insertions, 8 deletions
diff --git a/chip/stm32/system.c b/chip/stm32/system.c index 74e81d5a70..f5f7dff73d 100644 --- a/chip/stm32/system.c +++ b/chip/stm32/system.c @@ -9,16 +9,16 @@ #include "registers.h" #include "system.h" #include "task.h" +#include "util.h" #include "version.h" #include "watchdog.h" +/* TODO: Fake WP is stored at most significant bit of saved reset flags to save + * space. Remove it when we have real write protect pin */ + enum bkpdata_index { BKPDATA_INDEX_SCRATCHPAD, /* General-purpose scratchpad */ BKPDATA_INDEX_SAVED_RESET_FLAGS,/* Saved reset flags */ - BKPDATA_INDEX_FAKE_WP, /* Fake write-protect pin */ - /* TODO: Remove this when we have real - * write protect pin. - */ }; @@ -55,12 +55,15 @@ static void check_reset_cause(void) uint32_t raw_cause = STM32_RCC_CSR; uint32_t pwr_status = STM32_PWR_CSR; + uint32_t fake_wp = flags & 0x8000; + flags &= ~0x8000; + /* Clear the hardware reset cause by setting the RMVF bit */ STM32_RCC_CSR |= 1 << 24; /* Clear SBF in PWR_CSR */ STM32_PWR_CR |= 1 << 3; /* Clear saved reset flags */ - bkpdata_write(BKPDATA_INDEX_SAVED_RESET_FLAGS, 0); + bkpdata_write(BKPDATA_INDEX_SAVED_RESET_FLAGS, 0 | fake_wp); if (raw_cause & 0x60000000) { /* IWDG or WWDG @@ -140,9 +143,16 @@ void system_reset(int flags) { uint32_t save_flags = 0; + uint32_t fake_wp = + bkpdata_read(BKPDATA_INDEX_SAVED_RESET_FLAGS) & 0x8000; + /* Disable interrupts to avoid task swaps during reboot */ interrupt_disable(); + /* TODO: Check if a collision between reset flags and fake wp occurred. + * Remove this when we have real write protect pin. */ + ASSERT(!(system_get_reset_flags() & 0x8000)); + /* Save current reset reasons if necessary */ if (flags & SYSTEM_RESET_PRESERVE_FLAGS) save_flags = system_get_reset_flags() | RESET_FLAG_PRESERVED; @@ -154,7 +164,7 @@ void system_reset(int flags) if (flags & SYSTEM_RESET_HARD) save_flags |= RESET_FLAG_HARD; - bkpdata_write(BKPDATA_INDEX_SAVED_RESET_FLAGS, save_flags); + bkpdata_write(BKPDATA_INDEX_SAVED_RESET_FLAGS, save_flags | fake_wp); if (flags & SYSTEM_RESET_HARD) { /* Ask the watchdog to trigger a hard reboot */ @@ -210,12 +220,22 @@ const char *system_get_chip_revision(void) /* TODO: crosbug.com/p/12036 */ int system_set_fake_wp(int val) { - return bkpdata_write(BKPDATA_INDEX_FAKE_WP, (uint16_t)val); + uint16_t flags = bkpdata_read(BKPDATA_INDEX_SAVED_RESET_FLAGS); + + if (val) + flags |= 0x8000; + else + flags &= ~0x8000; + + return bkpdata_write(BKPDATA_INDEX_SAVED_RESET_FLAGS, flags); } /* TODO: crosbug.com/p/12036 */ int system_get_fake_wp(void) { - return bkpdata_read(BKPDATA_INDEX_FAKE_WP); + if (bkpdata_read(BKPDATA_INDEX_SAVED_RESET_FLAGS) & 0x8000) + return 1; + else + return 0; } |