The ESM (Error Signaling Module) is used to route error signals within the K3 SoCs somewhat similar to interrupts. The handling for these is different though, and can be routed for hardware error handling, to be handled by safety processor or just as error interrupts handled by the main processor. The u-boot level ESM driver is just used to configure the ESM signals so that they get routed to proper destination.

Signed-off-by: Tero Kristo t-kristo@ti.com --- doc/device-tree-bindings/misc/esm-k3.txt | 25 +++++++ drivers/misc/Kconfig | 5 ++ drivers/misc/Makefile | 1 + drivers/misc/k3_esm.c | 87 ++++++++++++++++++++++++ 4 files changed, 118 insertions(+) create mode 100644 doc/device-tree-bindings/misc/esm-k3.txt create mode 100644 drivers/misc/k3_esm.c

diff --git a/doc/device-tree-bindings/misc/esm-k3.txt b/doc/device-tree-bindings/misc/esm-k3.txt new file mode 100644 index 0000000000..01c8b6b294 --- /dev/null +++ b/doc/device-tree-bindings/misc/esm-k3.txt @@ -0,0 +1,25 @@ +Texas Instruments K3 ESM Binding +====================== + +ESM (Error Signaling Module) is an IP block on TI K3 devices that allows +handling of safety events somewhat similar to what interrupt controller +would do. The safety signals have their separate paths within the SoC, +and they are handled by the ESM, which routes them to the proper +destination, which can be system reset, interrupt controller, etc. In +the simplest configuration the signals are just routed to reset the +SoC. + +Required properties : +- compatible : "ti,j721e-esm" +- ti,esm-pins : integer array of esm events IDs to route to external event + pin which can be used to reset the SoC. The array can + have arbitrary amount of event IDs listed on it. + +Example +======= + + main_esm: esm@700000 { + compatible = "ti,j721e-esm"; + reg = <0x0 0x700000 0x0 0x1000>; + ti,esm-pins = <344>, <345>; + }; diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig index f18aa8f7ba..38588b2cbd 100644 --- a/drivers/misc/Kconfig +++ b/drivers/misc/Kconfig @@ -462,6 +462,11 @@ config IHS_FPGA gdsys devices, which supply the majority of the functionality offered by the devices. This driver supports both CON and CPU variants of the devices, depending on the device tree entry. +config ESM_K3 + bool "Enable K3 ESM driver" + depends on ARCH_K3 + help + Support ESM (Error Signaling Module) on TI K3 SoCs.

config MICROCHIP_FLEXCOM bool "Enable Microchip Flexcom driver" diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile index 2b843de93c..60406c3e0a 100644 --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile @@ -72,3 +72,4 @@ obj-$(CONFIG_WINBOND_W83627) += winbond_w83627.o obj-$(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 diff --git a/drivers/misc/k3_esm.c b/drivers/misc/k3_esm.c new file mode 100644 index 0000000000..8f270f3b5c --- /dev/null +++ b/drivers/misc/k3_esm.c @@ -0,0 +1,87 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Texas Instruments' K3 Error Signalling Module 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 <asm/io.h> +#include <dm/device_compat.h> + +#define ESM_SFT_RST 0x0c +#define ESM_SFT_RST_KEY 0x0f + +#define ESM_STS(i) (0x404 + (i) / 32 * 0x20) +#define ESM_PIN_EN_SET_OFFSET(i) (0x414 + (i) / 32 * 0x20) +#define ESM_PIN_MASK(i) BIT((i) & 0x1f) + +static void esm_pin_enable(void __iomem *base, int pin) +{ + /* Enable event */ + writel(ESM_PIN_MASK(pin), base + ESM_PIN_EN_SET_OFFSET(pin)); +} + +/** + * k3_esm_probe: configures ESM based on DT data + * + * Parses ESM info from device tree, and configures the module accordingly. + */ +static int k3_esm_probe(struct udevice *dev) +{ + int ret; + void __iomem *base; + int num_pins; + u32 *pins; + int i; + + base = dev_remap_addr_index(dev, 0); + if (!base) + return -ENODEV; + + num_pins = dev_read_size(dev, "ti,esm-pins"); + if (num_pins < 0) { + dev_err(dev, "ti,esm-pins property missing or invalid: %d\n", + num_pins); + return num_pins; + } + + num_pins /= sizeof(u32); + + pins = kmalloc(num_pins * sizeof(u32), __GFP_ZERO); + if (!pins) + return -ENOMEM; + + ret = dev_read_u32_array(dev, "ti,esm-pins", pins, num_pins); + if (ret < 0) { + dev_err(dev, "failed to read ti,esm-pins property: %d\n", + ret); + goto free_pins; + } + + /* Clear any pending events */ + writel(ESM_SFT_RST_KEY, base + ESM_SFT_RST); + + for (i = 0; i < num_pins; i++) + esm_pin_enable(base, pins[i]); + +free_pins: + kfree(pins); + return ret; +} + +static const struct udevice_id k3_esm_ids[] = { + { .compatible = "ti,j721e-esm" }, + {} +}; + +U_BOOT_DRIVER(k3_esm) = { + .name = "k3_esm", + .of_match = k3_esm_ids, + .id = UCLASS_MISC, + .probe = k3_esm_probe, +};

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, +};

The ESM handling on J7 processor board requires routing the MCU_SAFETY_ERROR signal to the PMIC on the board for critical safety error handling. The PMIC itself should then reset the board based on receiving it. Enable the support for the board by adding the esm node in place.

Signed-off-by: Tero Kristo t-kristo@ti.com --- .../arm/dts/k3-j721e-r5-common-proc-board-u-boot.dtsi | 11 +++++++++++ 1 file changed, 11 insertions(+) create mode 100644 arch/arm/dts/k3-j721e-r5-common-proc-board-u-boot.dtsi

diff --git a/arch/arm/dts/k3-j721e-r5-common-proc-board-u-boot.dtsi b/arch/arm/dts/k3-j721e-r5-common-proc-board-u-boot.dtsi new file mode 100644 index 0000000000..c6c60b44ec --- /dev/null +++ b/arch/arm/dts/k3-j721e-r5-common-proc-board-u-boot.dtsi @@ -0,0 +1,11 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020 Texas Instruments Incorporated - http://www.ti.com/ + */ + +&tps659413a { + esm: esm { + compatible = "ti,tps659413-esm"; + u-boot,dm-spl; + }; +};

Enable ESM modules for both PMIC and SoC side for proper watchdog handling on the board.

SPL_BOARD_INIT is also enabled so that the board init function probing the drivers is called.

Signed-off-by: Tero Kristo t-kristo@ti.com --- configs/j721e_evm_r5_defconfig | 3 +++ 1 file changed, 3 insertions(+)

diff --git a/configs/j721e_evm_r5_defconfig b/configs/j721e_evm_r5_defconfig index 19fbd450c7..a28ea30372 100644 --- a/configs/j721e_evm_r5_defconfig +++ b/configs/j721e_evm_r5_defconfig @@ -122,3 +122,6 @@ CONFIG_USB_GADGET_PRODUCT_NUM=0x6163 CONFIG_USB_GADGET_DOWNLOAD=y CONFIG_FS_EXT4=y CONFIG_FS_FAT_MAX_CLUSTSIZE=16384 +CONFIG_ESM_K3=y +CONFIG_ESM_PMIC=y +CONFIG_SPL_BOARD_INIT=y