Triple Modular Redundancy(TMR) subsystem contains three microblaze cores, subsystem is fault-tolerant and continues to operate nominally after encountering an error. Together with the capability to detect and recover from errors, the implementation ensures the reliability of the entire subsystem. TMR Manager is responsible for performing recovery of the subsystem detects the fault via a break signal it invokes microblaze software break handler which calls the tmr manager driver api to update the error count and status, added support for fault detection feature via sysfs interface. Usage: To know the break handler count(Error count): cat /sys/devices/platform/amba_pl/44a10000.tmr_manager/errcnt Signed-off-by: Appana Durga Kedareswara rao <appana.durga.kedareswara.rao@xxxxxxx> Reported-by: kernel test robot <lkp@xxxxxxxxx> --- Changes for v5: --> Fixed Unexpected indentation htmldoc warning in sysfs-driver-xilinx-tmr-manager. --> Removed sysfs references from the Kconfig description. Changes for v4: --> None. Changes for v3: --> Added Krzysztof Reviewed by. Changes for v2: --> Added minimum and maximum values for xlnx,magic1 property as suggested by Michal. --> Fixed 80 char limit in description as suggested by Michal. .../testing/sysfs-driver-xilinx-tmr-manager | 16 ++ MAINTAINERS | 7 + drivers/misc/Kconfig | 10 + drivers/misc/Makefile | 1 + drivers/misc/xilinx_tmr_manager.c | 220 ++++++++++++++++++ 5 files changed, 254 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-driver-xilinx-tmr-manager create mode 100644 drivers/misc/xilinx_tmr_manager.c diff --git a/Documentation/ABI/testing/sysfs-driver-xilinx-tmr-manager b/Documentation/ABI/testing/sysfs-driver-xilinx-tmr-manager new file mode 100644 index 000000000000..25c62c1c084f --- /dev/null +++ b/Documentation/ABI/testing/sysfs-driver-xilinx-tmr-manager @@ -0,0 +1,16 @@ +What: /sys/devices/platform/amba_pl/<dev>/errcnt +Date: Oct 2022 +Contact: appana.durga.kedareswara.rao@xxxxxxx +Description: This control file provides the fault detection count. + This file cannot be written. + Example: + # cat /sys/devices/platform/amba_pl/44a10000.tmr_manager/errcnt + 1 + +What: /sys/devices/platform/amba_pl/<dev>/dis_block_break +Date: Oct 2022 +Contact: appana.durga.kedareswara.rao@xxxxxxx +Description: Write any value to it, This control file enables the break signal. + This file is write only. + Example: + # echo <any value> > /sys/devices/platform/amba_pl/44a10000.tmr_manager/dis_block_break diff --git a/MAINTAINERS b/MAINTAINERS index 10c1344b4473..2cd9e7594759 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -13416,6 +13416,13 @@ W: http://www.monstr.eu/fdt/ T: git git://git.monstr.eu/linux-2.6-microblaze.git F: arch/microblaze/ +MICROBLAZE TMR MANAGER +M: Appana Durga Kedareswara rao <appana.durga.kedareswara.rao@xxxxxxx> +S: Supported +F: Documentation/ABI/testing/sysfs-driver-xilinx-tmr-manager +F: Documentation/devicetree/bindings/misc/xlnx,tmr-manager.yaml +F: drivers/misc/xilinx_tmr_manager.c + MICROCHIP AT91 DMA DRIVERS M: Ludovic Desroches <ludovic.desroches@xxxxxxxxxxxxx> M: Tudor Ambarus <tudor.ambarus@xxxxxxxxxxxxx> diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig index 358ad56f6524..a61445008f9e 100644 --- a/drivers/misc/Kconfig +++ b/drivers/misc/Kconfig @@ -496,6 +496,16 @@ config VCPU_STALL_DETECTOR If you do not intend to run this kernel as a guest, say N. +config TMR_MANAGER + tristate "Select TMR Manager" + depends on MICROBLAZE && MB_MANAGER + help + This option enables the driver developed for TMR Manager. + The Triple Modular Redundancy(TMR) manager provides support for + fault detection. + + Say N here unless you know what you are doing. + source "drivers/misc/c2port/Kconfig" source "drivers/misc/eeprom/Kconfig" source "drivers/misc/cb710/Kconfig" diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile index ac9b3e757ba1..b93b782a52f4 100644 --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile @@ -62,3 +62,4 @@ obj-$(CONFIG_HI6421V600_IRQ) += hi6421v600-irq.o obj-$(CONFIG_OPEN_DICE) += open-dice.o obj-$(CONFIG_GP_PCI1XXXX) += mchp_pci1xxxx/ obj-$(CONFIG_VCPU_STALL_DETECTOR) += vcpu_stall_detector.o +obj-$(CONFIG_TMR_MANAGER) += xilinx_tmr_manager.o diff --git a/drivers/misc/xilinx_tmr_manager.c b/drivers/misc/xilinx_tmr_manager.c new file mode 100644 index 000000000000..535f723c1a5a --- /dev/null +++ b/drivers/misc/xilinx_tmr_manager.c @@ -0,0 +1,220 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Xilinx TMR Subsystem. + * + * Copyright (C) 2022 Xilinx, Inc. + * + * Description: + * This driver is developed for TMR Manager,The Triple Modular Redundancy(TMR) + * Manager is responsible for handling the TMR subsystem state, including + * fault detection and error recovery. The core is triplicated in each of + * the sub-blocks in the TMR subsystem, and provides majority voting of + * its internal state provides soft error detection, correction and + * recovery. + */ + +#include <asm/xilinx_mb_manager.h> +#include <linux/module.h> +#include <linux/of_device.h> + +/* TMR Manager Register offsets */ +#define XTMR_MANAGER_CR_OFFSET 0x0 +#define XTMR_MANAGER_FFR_OFFSET 0x4 +#define XTMR_MANAGER_CMR0_OFFSET 0x8 +#define XTMR_MANAGER_CMR1_OFFSET 0xC +#define XTMR_MANAGER_BDIR_OFFSET 0x10 +#define XTMR_MANAGER_SEMIMR_OFFSET 0x1C + +/* Register Bitmasks/shifts */ +#define XTMR_MANAGER_CR_MAGIC1_MASK GENMASK(7, 0) +#define XTMR_MANAGER_CR_MAGIC2_MASK GENMASK(15, 8) +#define XTMR_MANAGER_CR_RIR_MASK BIT(16) +#define XTMR_MANAGER_FFR_LM12_MASK BIT(0) +#define XTMR_MANAGER_FFR_LM13_MASK BIT(1) +#define XTMR_MANAGER_FFR_LM23_MASK BIT(2) + +#define XTMR_MANAGER_CR_MAGIC2_SHIFT 4 +#define XTMR_MANAGER_CR_RIR_SHIFT 16 +#define XTMR_MANAGER_CR_BB_SHIFT 18 + +#define XTMR_MANAGER_MAGIC1_MAX_VAL 255 + +/** + * struct xtmr_manager_dev - Driver data for TMR Manager + * @regs: device physical base address + * @cr_val: control register value + * @magic1: Magic 1 hardware configuration value + * @err_cnt: error statistics count + * @phys_baseaddr: Physical base address + */ +struct xtmr_manager_dev { + void __iomem *regs; + u32 cr_val; + u32 magic1; + u32 err_cnt; + resource_size_t phys_baseaddr; +}; + +/* IO accessors */ +static inline void xtmr_manager_write(struct xtmr_manager_dev *xtmr_manager, + u32 addr, u32 value) +{ + iowrite32(value, xtmr_manager->regs + addr); +} + +static inline u32 xtmr_manager_read(struct xtmr_manager_dev *xtmr_manager, + u32 addr) +{ + return ioread32(xtmr_manager->regs + addr); +} + +static void xmb_manager_reset_handler(struct xtmr_manager_dev *xtmr_manager) +{ + /* Clear the FFR Register contents as a part of recovery process. */ + xtmr_manager_write(xtmr_manager, XTMR_MANAGER_FFR_OFFSET, 0); +} + +static void xmb_manager_update_errcnt(struct xtmr_manager_dev *xtmr_manager) +{ + xtmr_manager->err_cnt++; +} + +static ssize_t errcnt_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct xtmr_manager_dev *xtmr_manager = dev_get_drvdata(dev); + + return sysfs_emit(buf, "%x\n", xtmr_manager->err_cnt); +} +static DEVICE_ATTR_RO(errcnt); + +static ssize_t dis_block_break_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t size) +{ + struct xtmr_manager_dev *xtmr_manager = dev_get_drvdata(dev); + int ret; + long value; + + ret = kstrtoul(buf, 16, &value); + if (ret) + return ret; + + /* unblock the break signal*/ + xtmr_manager->cr_val &= ~(1 << XTMR_MANAGER_CR_BB_SHIFT); + xtmr_manager_write(xtmr_manager, XTMR_MANAGER_CR_OFFSET, + xtmr_manager->cr_val); + return size; +} +static DEVICE_ATTR_WO(dis_block_break); + +static struct attribute *xtmr_manager_dev_attrs[] = { + &dev_attr_dis_block_break.attr, + &dev_attr_errcnt.attr, + NULL, +}; +ATTRIBUTE_GROUPS(xtmr_manager_dev); + +static void xtmr_manager_init(struct xtmr_manager_dev *xtmr_manager) +{ + /* Clear the SEM interrupt mask register to disable the interrupt */ + xtmr_manager_write(xtmr_manager, XTMR_MANAGER_SEMIMR_OFFSET, 0); + + /* Allow recovery reset by default */ + xtmr_manager->cr_val = (1 << XTMR_MANAGER_CR_RIR_SHIFT) | + xtmr_manager->magic1; + xtmr_manager_write(xtmr_manager, XTMR_MANAGER_CR_OFFSET, + xtmr_manager->cr_val); + /* + * Configure Break Delay Initialization Register to zero so that + * break occurs immediately + */ + xtmr_manager_write(xtmr_manager, XTMR_MANAGER_BDIR_OFFSET, 0); + + /* + * To come out of break handler need to block the break signal + * in the tmr manager, update the xtmr_manager cr_val for the same + */ + xtmr_manager->cr_val |= (1 << XTMR_MANAGER_CR_BB_SHIFT); + + /* + * When the break vector gets asserted because of error injection, + * the break signal must be blocked before exiting from the + * break handler, Below api updates the TMR manager address and + * control register and error counter callback arguments, + * which will be used by the break handler to block the + * break and call the callback function. + */ + xmb_manager_register(xtmr_manager->phys_baseaddr, xtmr_manager->cr_val, + (void *)xmb_manager_update_errcnt, + xtmr_manager, (void *)xmb_manager_reset_handler); +} + +/** + * xtmr_manager_probe - Driver probe function + * @pdev: Pointer to the platform_device structure + * + * This is the driver probe routine. It does all the memory + * allocation for the device. + * + * Return: 0 on success and failure value on error + */ +static int xtmr_manager_probe(struct platform_device *pdev) +{ + struct xtmr_manager_dev *xtmr_manager; + struct resource *res; + int err; + + xtmr_manager = devm_kzalloc(&pdev->dev, sizeof(*xtmr_manager), + GFP_KERNEL); + if (!xtmr_manager) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + xtmr_manager->regs = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(xtmr_manager->regs)) + return PTR_ERR(xtmr_manager->regs); + + xtmr_manager->phys_baseaddr = res->start; + + err = of_property_read_u32(pdev->dev.of_node, "xlnx,magic1", + &xtmr_manager->magic1); + if (err < 0) { + dev_err(&pdev->dev, "unable to read xlnx,magic1 property"); + return err; + } + + if (xtmr_manager->magic1 > XTMR_MANAGER_MAGIC1_MAX_VAL) { + dev_err(&pdev->dev, "invalid xlnx,magic1 property value"); + return -EINVAL; + } + + /* Initialize TMR Manager */ + xtmr_manager_init(xtmr_manager); + + platform_set_drvdata(pdev, xtmr_manager); + + return 0; +} + +static const struct of_device_id xtmr_manager_of_match[] = { + { + .compatible = "xlnx,tmr-manager-1.0", + }, + { /* end of table */ } +}; +MODULE_DEVICE_TABLE(of, xtmr_manager_of_match); + +static struct platform_driver xtmr_manager_driver = { + .driver = { + .name = "xilinx-tmr_manager", + .of_match_table = xtmr_manager_of_match, + .dev_groups = xtmr_manager_dev_groups, + }, + .probe = xtmr_manager_probe, +}; +module_platform_driver(xtmr_manager_driver); + +MODULE_AUTHOR("Xilinx, Inc"); +MODULE_DESCRIPTION("Xilinx TMR Manager Driver"); +MODULE_LICENSE("GPL"); -- 2.25.1
