From dd6fdb92eab77b6832d1975418b4805260b2a035 Mon Sep 17 00:00:00 2001 From: Marius Vikhammer Date: Mon, 26 Aug 2024 11:59:51 +0800 Subject: [PATCH] docs(system): add cpu lock up description --- components/esp_system/include/esp_system.h | 2 +- components/soc/esp32p4/include/soc/Kconfig.soc_caps.in | 4 ++++ components/soc/esp32p4/include/soc/soc_caps.h | 2 ++ docs/en/api-guides/fatal-errors.rst | 10 ++++++++++ 4 files changed, 17 insertions(+), 1 deletion(-) diff --git a/components/esp_system/include/esp_system.h b/components/esp_system/include/esp_system.h index 73b8deec08..c1c90362e4 100644 --- a/components/esp_system/include/esp_system.h +++ b/components/esp_system/include/esp_system.h @@ -37,7 +37,7 @@ typedef enum { ESP_RST_JTAG, //!< Reset by JTAG ESP_RST_EFUSE, //!< Reset due to efuse error ESP_RST_PWR_GLITCH, //!< Reset due to power glitch detected - ESP_RST_CPU_LOCKUP, //!< Reset due to CPU lock up + ESP_RST_CPU_LOCKUP, //!< Reset due to CPU lock up (double exception) } esp_reset_reason_t; /** diff --git a/components/soc/esp32p4/include/soc/Kconfig.soc_caps.in b/components/soc/esp32p4/include/soc/Kconfig.soc_caps.in index d8aaf2ded4..022dd58197 100644 --- a/components/soc/esp32p4/include/soc/Kconfig.soc_caps.in +++ b/components/soc/esp32p4/include/soc/Kconfig.soc_caps.in @@ -511,6 +511,10 @@ config SOC_CPU_PMP_REGION_GRANULARITY int default 128 +config SOC_CPU_HAS_LOCKUP_RESET + bool + default y + config SOC_DS_SIGNATURE_MAX_BIT_LEN int default 4096 diff --git a/components/soc/esp32p4/include/soc/soc_caps.h b/components/soc/esp32p4/include/soc/soc_caps.h index a47cf9a36a..a8b567d41d 100644 --- a/components/soc/esp32p4/include/soc/soc_caps.h +++ b/components/soc/esp32p4/include/soc/soc_caps.h @@ -185,6 +185,8 @@ #define SOC_CPU_IDRAM_SPLIT_USING_PMP 1 #define SOC_CPU_PMP_REGION_GRANULARITY 128 +#define SOC_CPU_HAS_LOCKUP_RESET 1 + /*-------------------------- DIGITAL SIGNATURE CAPS ----------------------------------------*/ /** The maximum length of a Digital Signature in bits. */ #define SOC_DS_SIGNATURE_MAX_BIT_LEN (4096) diff --git a/docs/en/api-guides/fatal-errors.rst b/docs/en/api-guides/fatal-errors.rst index 389e90ea4a..66c1d64cb8 100644 --- a/docs/en/api-guides/fatal-errors.rst +++ b/docs/en/api-guides/fatal-errors.rst @@ -528,6 +528,16 @@ The backtrace should point to the function where stack smashing has occurred. Ch .. |CACHE_ERR_MSG| replace:: Cache error .. |STACK_OVERFLOW| replace:: Stack overflow + +.. only:: SOC_CPU_HAS_LOCKUP_RESET + + CPU Lockup + ^^^^^^^^^^ + A CPU lockup reset happens when there is a double exception, i.e. when an exception occurs while the CPU is already in an exception handler. The most common cause for this is when the cache is in such a state that accessing external memory not possible. If this is the case then the panic handler will crash as well due to being unable to fetch instructions or read data. + + If this is the case you can try placing the panic handler code in IRAM, which can be accessed when cache is disabled, to get more information about the cause of the lockup. This can be done with :ref:`CONFIG_ESP_PANIC_HANDLER_IRAM`. + + Undefined Behavior Sanitizer (UBSAN) Checks ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^