The ESM (Error Signal Monitor) is used on certain PMIC versions to handle error signals propagating from rest of the system. If these reach the PMIC, it is typically a last resort fatal error which requires a system reset. The ESM driver does the proper configuration for the ESM module to reach this end goal. Initially, only TPS65941 PMIC is supported for this.
Signed-off-by: Tero Kristo t-kristo@ti.com --- doc/device-tree-bindings/misc/esm-pmic.txt | 19 ++++++ drivers/misc/Kconfig | 7 +++ drivers/misc/Makefile | 1 + drivers/misc/esm_pmic.c | 69 ++++++++++++++++++++++ 4 files changed, 96 insertions(+) create mode 100644 doc/device-tree-bindings/misc/esm-pmic.txt create mode 100644 drivers/misc/esm_pmic.c
diff --git a/doc/device-tree-bindings/misc/esm-pmic.txt b/doc/device-tree-bindings/misc/esm-pmic.txt new file mode 100644 index 0000000000..a60ad74679 --- /dev/null +++ b/doc/device-tree-bindings/misc/esm-pmic.txt @@ -0,0 +1,19 @@ +PMIC ESM Binding +====================== + +Certain Power Management ICs contain safety handling logic within them, +allowing automatic reset of the board in case a safety error is signaled. +For this purpose, ESM (Error Signal Monitor) is implemented within +the PMIC running its own state machine. + +Required properties : +- compatible : "ti,tps659413-esm" + +Example +======= + +&tps659413a { + esm: esm { + compatible = "ti,tps659413-esm"; + }; +}; diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig index 38588b2cbd..766402745d 100644 --- a/drivers/misc/Kconfig +++ b/drivers/misc/Kconfig @@ -486,4 +486,11 @@ config K3_AVS0 optimized voltage from the efuse, so that it can be programmed to the PMIC on board.
+config ESM_PMIC + bool "Enable PMIC ESM driver" + depends on DM_PMIC + help + Support ESM (Error Signal Monitor) on PMIC devices. ESM is used + typically to reboot the board in error condition. + endmenu diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile index 60406c3e0a..68e0e7ad17 100644 --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile @@ -73,3 +73,4 @@ obj-$(CONFIG_JZ4780_EFUSE) += jz4780_efuse.o obj-$(CONFIG_MICROCHIP_FLEXCOM) += microchip_flexcom.o obj-$(CONFIG_K3_AVS0) += k3_avs.o obj-$(CONFIG_ESM_K3) += k3_esm.o +obj-$(CONFIG_ESM_PMIC) += esm_pmic.o diff --git a/drivers/misc/esm_pmic.c b/drivers/misc/esm_pmic.c new file mode 100644 index 0000000000..92c8d68f7c --- /dev/null +++ b/drivers/misc/esm_pmic.c @@ -0,0 +1,69 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * PMIC Error Signal Monitor driver + * + * Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com/ + * Tero Kristo t-kristo@ti.com + * + */ + +#include <common.h> +#include <dm.h> +#include <errno.h> +#include <power/pmic.h> +#include <dm/device_compat.h> + +#define INT_ESM_REG 0x6c +#define INT_ESM_MASK 0x3f + +#define ESM_MCU_START_REG 0x8f + +#define ESM_MCU_START BIT(0) + +#define ESM_MCU_MODE_CFG_REG 0x92 + +#define ESM_MCU_EN BIT(6) +#define ESM_MCU_ENDRV BIT(5) + +/** + * pmic_esm_probe: configures and enables PMIC ESM functionality + * + * Configures ESM PMIC support and enables it. + */ +static int pmic_esm_probe(struct udevice *dev) +{ + int ret; + + ret = pmic_reg_write(dev->parent, INT_ESM_REG, INT_ESM_MASK); + if (ret) { + dev_err(dev, "clearing ESM irqs failed: %d\n", ret); + return ret; + } + + ret = pmic_reg_write(dev->parent, ESM_MCU_MODE_CFG_REG, + ESM_MCU_EN | ESM_MCU_ENDRV); + if (ret) { + dev_err(dev, "setting ESM mode failed: %d\n", ret); + return ret; + } + + ret = pmic_reg_write(dev->parent, ESM_MCU_START_REG, ESM_MCU_START); + if (ret) { + dev_err(dev, "starting ESM failed: %d\n", ret); + return ret; + } + + return 0; +} + +static const struct udevice_id pmic_esm_ids[] = { + { .compatible = "ti,tps659413-esm" }, + {} +}; + +U_BOOT_DRIVER(pmic_esm) = { + .name = "esm_pmic", + .of_match = pmic_esm_ids, + .id = UCLASS_MISC, + .probe = pmic_esm_probe, +};