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| author | Wealian Liao <whliao@nuvoton.corp-partner.google.com> | 2021-09-06 15:40:50 +0800 |
|---|---|---|
| committer | Commit Bot <commit-bot@chromium.org> | 2021-09-13 16:35:33 +0000 |
| commit | dabbc85c514a360250d1a49efd271b0465115bb0 (patch) | |
| tree | ea01457c1e14c1470869d0dd0105c6a3fcca23ab | |
| parent | 4a0368676c647d139226011796c7670b0981b9ed (diff) | |
| download | chrome-ec-dabbc85c514a360250d1a49efd271b0465115bb0.tar.gz | |
zephyr: Use NOP to wait for the external reset from H1
The current initial stage couldn't use the kernel delay function. Use
CPU nop instruction to wait for the external reset from H1.
BUG=b:182875520
BRANCH=none
TEST=Enable CONFIG_BOARD_RESET_AFTER_POWER_ON for evb & toggle GPIO.
Check the delay is 2 seconds.
Signed-off-by: Wealian Liao <whliao@nuvoton.corp-partner.google.com>
Change-Id: If221181358c2a4df758d5bb9b57c3fbba31100aa
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3143633
Reviewed-by: Keith Short <keithshort@chromium.org>
Commit-Queue: Keith Short <keithshort@chromium.org>
| -rw-r--r-- | zephyr/Kconfig | 16 | ||||
| -rw-r--r-- | zephyr/shim/src/system.c | 21 |
2 files changed, 31 insertions, 6 deletions
diff --git a/zephyr/Kconfig b/zephyr/Kconfig index 6253631156..58961630ce 100644 --- a/zephyr/Kconfig +++ b/zephyr/Kconfig @@ -115,6 +115,22 @@ config PLATFORM_EC_BOARD_RESET_AFTER_POWER_ON the EC starts up, performs some amount of processing and then gets a reset that it is not expecting. +config PLATFORM_EC_WAIT_RESET_CYCLES_PER_ITERATION + int "CPU execution cycle per iteration for waiting the H1 reset" + default 4 + depends on PLATFORM_EC_BOARD_RESET_AFTER_POWER_ON + help + This options specifies the number of CPU execution cycles per delay + loop iteration, while waiting for the H1 to reset. + +config PLATFORM_EC_PREINIT_HW_CYCLES_PER_SEC + int "CPU power up clock cycle per second" + default 100000000 + depends on PLATFORM_EC_BOARD_RESET_AFTER_POWER_ON + help + This option specifies the frequency (in Hz) of the CPU core when + coming out of a power on reset. + config PLATFORM_EC_BRINGUP bool "Enable early bringup debugging features" help diff --git a/zephyr/shim/src/system.c b/zephyr/shim/src/system.c index 2614a1fcb4..8db8ba437a 100644 --- a/zephyr/shim/src/system.c +++ b/zephyr/shim/src/system.c @@ -24,6 +24,11 @@ DT_PROP(DT_PATH(named_bbram_regions, node), offset) #define GET_BBRAM_SIZE(node) DT_PROP(DT_PATH(named_bbram_regions, node), size) +/* 2 second delay for waiting the H1 reset */ +#define WAIT_RESET_TIME \ + (CONFIG_PLATFORM_EC_PREINIT_HW_CYCLES_PER_SEC * 2 / \ + CONFIG_PLATFORM_EC_WAIT_RESET_CYCLES_PER_ITERATION) + LOG_MODULE_REGISTER(shim_system, LOG_LEVEL_ERR); STATIC_IF_NOT(CONFIG_ZTEST) const struct device *bbram_dev; @@ -355,13 +360,17 @@ static int system_preinitialize(const struct device *unused) * previous power-on, and treat the second reset as a power-on instead * of a reset. */ - if (IS_ENABLED(CONFIG_BOARD_RESET_AFTER_POWER_ON) && - system_get_reset_flags() & EC_RESET_FLAG_INITIAL_PWR) { - /* TODO(b/182875520): Change to use 2 second delay. */ - while (1) - continue; +#ifdef CONFIG_BOARD_RESET_AFTER_POWER_ON + if (system_get_reset_flags() & EC_RESET_FLAG_INITIAL_PWR) { + /* + * The current initial stage couldn't use the kernel delay + * function. Use CPU nop instruction to wait for the external + * reset from H1. + */ + for (uint32_t i = WAIT_RESET_TIME; i; i--) + arch_nop(); } - +#endif return 0; } |