From b8fc5eecdc5d33cf261986436597b5482ab856da Mon Sep 17 00:00:00 2001 From: Sander Vanheule Date: Sun, 14 Nov 2021 19:45:32 +0100 Subject: [PATCH] realtek: Backport Realtek Otto WDT driver Add patch submitted upstream to linux-watchdog and replace the MIPS architecture symbols. Requires one extra patch for the DIV_ROUND_* macros, which have moved to a different header since 5.10. Signed-off-by: Sander Vanheule Tested-by: Stijn Segers Tested-by: Paul Fertser Tested-by: Stijn Tintel --- ...hdog-add-realtek-otto-watchdog-timer.patch | 456 ++++++++++++++++++ ...date-dependency-for-realtek-otto-wdt.patch | 17 + ...308-otto-wdt-fix-missing-math-header.patch | 13 + 3 files changed, 486 insertions(+) create mode 100644 target/linux/realtek/patches-5.10/100-watchdog-add-realtek-otto-watchdog-timer.patch create mode 100644 target/linux/realtek/patches-5.10/307-wdt-update-dependency-for-realtek-otto-wdt.patch create mode 100644 target/linux/realtek/patches-5.10/308-otto-wdt-fix-missing-math-header.patch diff --git a/target/linux/realtek/patches-5.10/100-watchdog-add-realtek-otto-watchdog-timer.patch b/target/linux/realtek/patches-5.10/100-watchdog-add-realtek-otto-watchdog-timer.patch new file mode 100644 index 0000000000..5aa988dc55 --- /dev/null +++ b/target/linux/realtek/patches-5.10/100-watchdog-add-realtek-otto-watchdog-timer.patch @@ -0,0 +1,456 @@ +From 2dbf0c6e0eebf523008c15794434d2d1a9b1260e Mon Sep 17 00:00:00 2001 +Message-Id: <2dbf0c6e0eebf523008c15794434d2d1a9b1260e.1636018117.git.sander@svanheule.net> +In-Reply-To: +References: +From: Sander Vanheule +Date: Sun, 3 Oct 2021 09:25:27 +0200 +Subject: [PATCH v3 2/2] watchdog: Add Realtek Otto watchdog timer + +Realtek MIPS SoCs (platform name Otto) have a watchdog timer with +pretimeout notifitication support. The WDT can (partially) hard reset, +or soft reset the SoC. + +This driver implements all features as described in the devicetree +binding, except the phase2 interrupt, and also functions as a restart +handler. The cpu reset mode is considered to be a "warm" restart, since +this mode does not reset all peripherals. Being an embedded system +though, the "cpu" and "software" modes will still cause the bootloader +to run on restart. + +It is not known how a forced system reset can be disabled on the +supported platforms. This means that the phase2 interrupt will only fire +at the same time as reset, so implementing phase2 is of little use. + +Signed-off-by: Sander Vanheule +--- + MAINTAINERS | 7 + + drivers/watchdog/Kconfig | 13 + + drivers/watchdog/Makefile | 1 + + drivers/watchdog/realtek_otto_wdt.c | 361 ++++++++++++++++++++++++++++ + 4 files changed, 382 insertions(+) + create mode 100644 drivers/watchdog/realtek_otto_wdt.c + +diff --git a/MAINTAINERS b/MAINTAINERS +index 2c9070aeba2a..54c8f788d3e5 100644 +--- a/MAINTAINERS ++++ b/MAINTAINERS +@@ -15991,6 +15991,13 @@ S: Maintained + F: include/sound/rt*.h + F: sound/soc/codecs/rt* + ++REALTEK OTTO WATCHDOG ++M: Sander Vanheule ++L: linux-watchdog@vger.kernel.org ++S: Maintained ++F: Documentation/devicetree/bindings/watchdog/realtek,otto-wdt.yaml ++F: driver/watchdog/realtek_otto_wdt.c ++ + REALTEK RTL83xx SMI DSA ROUTER CHIPS + M: Linus Walleij + S: Maintained +diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig +index bf59faeb3de1..d308e13a9aa1 100644 +--- a/drivers/watchdog/Kconfig ++++ b/drivers/watchdog/Kconfig +@@ -954,6 +954,19 @@ config RTD119X_WATCHDOG + Say Y here to include support for the watchdog timer in + Realtek RTD1295 SoCs. + ++config REALTEK_OTTO_WDT ++ tristate "Realtek Otto MIPS watchdog support" ++ depends on MACH_REALTEK_RTL || COMPILE_TEST ++ depends on COMMON_CLK ++ select WATCHDOG_CORE ++ default MACH_REALTEK_RTL ++ help ++ Say Y here to include support for the watchdog timer on Realtek ++ RTL838x, RTL839x, RTL930x SoCs. This watchdog has pretimeout ++ notifications and system reset on timeout. ++ ++ When built as a module this will be called realtek_otto_wdt. ++ + config SPRD_WATCHDOG + tristate "Spreadtrum watchdog support" + depends on ARCH_SPRD || COMPILE_TEST +diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile +index 1bd2d6f37c53..a8dccf819163 100644 +--- a/drivers/watchdog/Makefile ++++ b/drivers/watchdog/Makefile +@@ -171,6 +171,7 @@ obj-$(CONFIG_IMGPDC_WDT) += imgpdc_wdt.o + obj-$(CONFIG_MT7621_WDT) += mt7621_wdt.o + obj-$(CONFIG_PIC32_WDT) += pic32-wdt.o + obj-$(CONFIG_PIC32_DMT) += pic32-dmt.o ++obj-$(CONFIG_REALTEK_OTTO_WDT) += realtek_otto_wdt.o + + # PARISC Architecture + +diff --git a/drivers/watchdog/realtek_otto_wdt.c b/drivers/watchdog/realtek_otto_wdt.c +new file mode 100644 +index 000000000000..48bc8dfefc25 +--- /dev/null ++++ b/drivers/watchdog/realtek_otto_wdt.c +@@ -0,0 +1,361 @@ ++// SPDX-License-Identifier: GPL-2.0-only ++ ++/* ++ * Realtek Otto MIPS platform watchdog ++ * ++ * Watchdog timer that will reset the system after timeout, using the selected ++ * reset mode. ++ * ++ * Counter scaling and timeouts: ++ * - Base prescale of (2 << 25), providing tick duration T_0: 168ms @ 200MHz ++ * - PRESCALE: logarithmic prescaler adding a factor of {1, 2, 4, 8} ++ * - Phase 1: Times out after (PHASE1 + 1) × PRESCALE × T_0 ++ * Generates an interrupt, WDT cannot be stopped after phase 1 ++ * - Phase 2: starts after phase 1, times out after (PHASE2 + 1) × PRESCALE × T_0 ++ * Resets the system according to RST_MODE ++ */ ++ ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++ ++#define OTTO_WDT_REG_CNTR 0x0 ++#define OTTO_WDT_CNTR_PING BIT(31) ++ ++#define OTTO_WDT_REG_INTR 0x4 ++#define OTTO_WDT_INTR_PHASE_1 BIT(31) ++#define OTTO_WDT_INTR_PHASE_2 BIT(30) ++ ++#define OTTO_WDT_REG_CTRL 0x8 ++#define OTTO_WDT_CTRL_ENABLE BIT(31) ++#define OTTO_WDT_CTRL_PRESCALE GENMASK(30, 29) ++#define OTTO_WDT_CTRL_PHASE1 GENMASK(26, 22) ++#define OTTO_WDT_CTRL_PHASE2 GENMASK(19, 15) ++#define OTTO_WDT_CTRL_RST_MODE GENMASK(1, 0) ++#define OTTO_WDT_MODE_SOC 0 ++#define OTTO_WDT_MODE_CPU 1 ++#define OTTO_WDT_MODE_SOFTWARE 2 ++#define OTTO_WDT_CTRL_DEFAULT OTTO_WDT_MODE_CPU ++ ++#define OTTO_WDT_PRESCALE_MAX 3 ++ ++/* ++ * One higher than the max values contained in PHASE{1,2}, since a value of 0 ++ * corresponds to one tick. ++ */ ++#define OTTO_WDT_PHASE_TICKS_MAX 32 ++ ++/* ++ * The maximum reset delay is actually 2×32 ticks, but that would require large ++ * pretimeout values for timeouts longer than 32 ticks. Limit the maximum timeout ++ * to 32 + 1 to ensure small pretimeout values can be configured as expected. ++ */ ++#define OTTO_WDT_TIMEOUT_TICKS_MAX (OTTO_WDT_PHASE_TICKS_MAX + 1) ++ ++struct otto_wdt_ctrl { ++ struct watchdog_device wdev; ++ struct device *dev; ++ void __iomem *base; ++ struct clk *clk; ++ int irq_phase1; ++}; ++ ++static int otto_wdt_start(struct watchdog_device *wdev) ++{ ++ struct otto_wdt_ctrl *ctrl = watchdog_get_drvdata(wdev); ++ u32 v; ++ ++ v = ioread32(ctrl->base + OTTO_WDT_REG_CTRL); ++ v |= OTTO_WDT_CTRL_ENABLE; ++ iowrite32(v, ctrl->base + OTTO_WDT_REG_CTRL); ++ ++ return 0; ++} ++ ++static int otto_wdt_stop(struct watchdog_device *wdev) ++{ ++ struct otto_wdt_ctrl *ctrl = watchdog_get_drvdata(wdev); ++ u32 v; ++ ++ v = ioread32(ctrl->base + OTTO_WDT_REG_CTRL); ++ v &= ~OTTO_WDT_CTRL_ENABLE; ++ iowrite32(v, ctrl->base + OTTO_WDT_REG_CTRL); ++ ++ return 0; ++} ++ ++static int otto_wdt_ping(struct watchdog_device *wdev) ++{ ++ struct otto_wdt_ctrl *ctrl = watchdog_get_drvdata(wdev); ++ ++ iowrite32(OTTO_WDT_CNTR_PING, ctrl->base + OTTO_WDT_REG_CNTR); ++ ++ return 0; ++} ++ ++static int otto_wdt_tick_ms(struct otto_wdt_ctrl *ctrl, int prescale) ++{ ++ unsigned int rate_khz = clk_get_rate(ctrl->clk) / 1000; ++ ++ if (!rate_khz) ++ return 0; ++ ++ return DIV_ROUND_CLOSEST(1 << (25 + prescale), rate_khz); ++} ++ ++/* ++ * The timer asserts the PHASE1/PHASE2 IRQs when the number of ticks exceeds ++ * the value stored in those fields. This means each phase will run for at least ++ * one tick, so small values need to be clamped to correctly reflect the timeout. ++ */ ++static inline unsigned int div_round_ticks(unsigned int val, unsigned int tick_duration, ++ unsigned int min_ticks) ++{ ++ return max(min_ticks, DIV_ROUND_UP(val, tick_duration)); ++} ++ ++static int otto_wdt_determine_timeouts(struct watchdog_device *wdev, unsigned int timeout, ++ unsigned int pretimeout) ++{ ++ struct otto_wdt_ctrl *ctrl = watchdog_get_drvdata(wdev); ++ unsigned int pretimeout_ms = pretimeout * 1000; ++ unsigned int timeout_ms = timeout * 1000; ++ unsigned int prescale_next = 0; ++ unsigned int phase1_ticks; ++ unsigned int phase2_ticks; ++ unsigned int total_ticks; ++ unsigned int prescale; ++ unsigned int tick_ms; ++ u32 v; ++ ++ do { ++ prescale = prescale_next; ++ if (prescale > OTTO_WDT_PRESCALE_MAX) ++ return -EINVAL; ++ ++ tick_ms = otto_wdt_tick_ms(ctrl, prescale); ++ total_ticks = div_round_ticks(timeout_ms, tick_ms, 2); ++ phase1_ticks = div_round_ticks(timeout_ms - pretimeout_ms, tick_ms, 1); ++ phase2_ticks = total_ticks - phase1_ticks; ++ ++ prescale_next++; ++ } while (phase1_ticks > OTTO_WDT_PHASE_TICKS_MAX ++ || phase2_ticks > OTTO_WDT_PHASE_TICKS_MAX); ++ ++ v = ioread32(ctrl->base + OTTO_WDT_REG_CTRL); ++ ++ v &= ~(OTTO_WDT_CTRL_PRESCALE | OTTO_WDT_CTRL_PHASE1 | OTTO_WDT_CTRL_PHASE2); ++ v |= FIELD_PREP(OTTO_WDT_CTRL_PHASE1, phase1_ticks - 1); ++ v |= FIELD_PREP(OTTO_WDT_CTRL_PHASE2, phase2_ticks - 1); ++ v |= FIELD_PREP(OTTO_WDT_CTRL_PRESCALE, prescale); ++ ++ iowrite32(v, ctrl->base + OTTO_WDT_REG_CTRL); ++ ++ timeout_ms = total_ticks * tick_ms; ++ ctrl->wdev.timeout = timeout_ms / 1000; ++ ++ pretimeout_ms = phase2_ticks * tick_ms; ++ ctrl->wdev.pretimeout = pretimeout_ms / 1000; ++ ++ return 0; ++} ++ ++static int otto_wdt_set_timeout(struct watchdog_device *wdev, unsigned int val) ++{ ++ return otto_wdt_determine_timeouts(wdev, val, min(wdev->pretimeout, val - 1)); ++} ++ ++static int otto_wdt_set_pretimeout(struct watchdog_device *wdev, unsigned int val) ++{ ++ return otto_wdt_determine_timeouts(wdev, wdev->timeout, val); ++} ++ ++static int otto_wdt_restart(struct watchdog_device *wdev, unsigned long reboot_mode, ++ void *data) ++{ ++ struct otto_wdt_ctrl *ctrl = watchdog_get_drvdata(wdev); ++ u32 reset_mode; ++ u32 v; ++ ++ disable_irq(ctrl->irq_phase1); ++ ++ switch (reboot_mode) { ++ case REBOOT_SOFT: ++ reset_mode = OTTO_WDT_MODE_SOFTWARE; ++ break; ++ case REBOOT_WARM: ++ reset_mode = OTTO_WDT_MODE_CPU; ++ break; ++ default: ++ reset_mode = OTTO_WDT_MODE_SOC; ++ break; ++ } ++ ++ /* Configure for shortest timeout and wait for reset to occur */ ++ v = FIELD_PREP(OTTO_WDT_CTRL_RST_MODE, reset_mode) | OTTO_WDT_CTRL_ENABLE; ++ iowrite32(v, ctrl->base + OTTO_WDT_REG_CTRL); ++ ++ mdelay(3 * otto_wdt_tick_ms(ctrl, 0)); ++ ++ return 0; ++} ++ ++static irqreturn_t otto_wdt_phase1_isr(int irq, void *dev_id) ++{ ++ struct otto_wdt_ctrl *ctrl = dev_id; ++ ++ iowrite32(OTTO_WDT_INTR_PHASE_1, ctrl->base + OTTO_WDT_REG_INTR); ++ dev_crit(ctrl->dev, "phase 1 timeout\n"); ++ watchdog_notify_pretimeout(&ctrl->wdev); ++ ++ return IRQ_HANDLED; ++} ++ ++static const struct watchdog_ops otto_wdt_ops = { ++ .owner = THIS_MODULE, ++ .start = otto_wdt_start, ++ .stop = otto_wdt_stop, ++ .ping = otto_wdt_ping, ++ .set_timeout = otto_wdt_set_timeout, ++ .set_pretimeout = otto_wdt_set_pretimeout, ++ .restart = otto_wdt_restart, ++}; ++ ++static const struct watchdog_info otto_wdt_info = { ++ .identity = "Realtek Otto watchdog timer", ++ .options = WDIOF_KEEPALIVEPING | ++ WDIOF_MAGICCLOSE | ++ WDIOF_SETTIMEOUT | ++ WDIOF_PRETIMEOUT, ++}; ++ ++static int otto_wdt_probe_reset_mode(struct otto_wdt_ctrl *ctrl) ++{ ++ static const char *mode_property = "realtek,reset-mode"; ++ const struct fwnode_handle *node = ctrl->dev->fwnode; ++ int mode_count; ++ u32 mode; ++ u32 v; ++ ++ if (!node) ++ return -ENXIO; ++ ++ mode_count = fwnode_property_string_array_count(node, mode_property); ++ if (mode_count < 0) ++ return mode_count; ++ else if (mode_count == 0) ++ return 0; ++ else if (mode_count != 1) ++ return -EINVAL; ++ ++ if (fwnode_property_match_string(node, mode_property, "soc") == 0) ++ mode = OTTO_WDT_MODE_SOC; ++ else if (fwnode_property_match_string(node, mode_property, "cpu") == 0) ++ mode = OTTO_WDT_MODE_CPU; ++ else if (fwnode_property_match_string(node, mode_property, "software") == 0) ++ mode = OTTO_WDT_MODE_SOFTWARE; ++ else ++ return -EINVAL; ++ ++ v = ioread32(ctrl->base + OTTO_WDT_REG_CTRL); ++ v &= ~OTTO_WDT_CTRL_RST_MODE; ++ v |= FIELD_PREP(OTTO_WDT_CTRL_RST_MODE, mode); ++ iowrite32(v, ctrl->base + OTTO_WDT_REG_CTRL); ++ ++ return 0; ++} ++ ++static int otto_wdt_probe(struct platform_device *pdev) ++{ ++ struct device *dev = &pdev->dev; ++ struct otto_wdt_ctrl *ctrl; ++ unsigned int max_tick_ms; ++ int ret; ++ ++ ctrl = devm_kzalloc(dev, sizeof(*ctrl), GFP_KERNEL); ++ if (!ctrl) ++ return -ENOMEM; ++ ++ ctrl->dev = dev; ++ ctrl->base = devm_platform_ioremap_resource(pdev, 0); ++ if (IS_ERR(ctrl->base)) ++ return PTR_ERR(ctrl->base); ++ ++ /* Clear any old interrupts and reset initial state */ ++ iowrite32(OTTO_WDT_INTR_PHASE_1 | OTTO_WDT_INTR_PHASE_2, ++ ctrl->base + OTTO_WDT_REG_INTR); ++ iowrite32(OTTO_WDT_CTRL_DEFAULT, ctrl->base + OTTO_WDT_REG_CTRL); ++ ++ ctrl->clk = devm_clk_get(dev, NULL); ++ if (IS_ERR(ctrl->clk)) ++ return dev_err_probe(dev, PTR_ERR(ctrl->clk), "Failed to get clock\n"); ++ ++ ctrl->irq_phase1 = platform_get_irq_byname(pdev, "phase1"); ++ if (ctrl->irq_phase1 < 0) ++ return dev_err_probe(dev, ctrl->irq_phase1, "phase1 IRQ not found\n"); ++ ++ ret = devm_request_irq(dev, ctrl->irq_phase1, otto_wdt_phase1_isr, 0, ++ "realtek-otto-wdt", ctrl); ++ if (ret) ++ return dev_err_probe(dev, ret, "Failed to get IRQ for phase1\n"); ++ ++ ret = otto_wdt_probe_reset_mode(ctrl); ++ if (ret) ++ return dev_err_probe(dev, ret, "Invalid reset mode specified\n"); ++ ++ ctrl->wdev.parent = dev; ++ ctrl->wdev.info = &otto_wdt_info; ++ ctrl->wdev.ops = &otto_wdt_ops; ++ ++ /* ++ * Since pretimeout cannot be disabled, min. timeout is twice the ++ * subsystem resolution. max. timeout is ca. 43s at a bus clock of 200MHz. ++ */ ++ ctrl->wdev.min_timeout = 2; ++ max_tick_ms = otto_wdt_tick_ms(ctrl, OTTO_WDT_PRESCALE_MAX); ++ ctrl->wdev.max_hw_heartbeat_ms = max_tick_ms * OTTO_WDT_TIMEOUT_TICKS_MAX; ++ ctrl->wdev.timeout = min(30U, ctrl->wdev.max_hw_heartbeat_ms / 1000); ++ ++ watchdog_set_drvdata(&ctrl->wdev, ctrl); ++ watchdog_init_timeout(&ctrl->wdev, 0, dev); ++ watchdog_stop_on_reboot(&ctrl->wdev); ++ watchdog_set_restart_priority(&ctrl->wdev, 128); ++ ++ ret = otto_wdt_determine_timeouts(&ctrl->wdev, ctrl->wdev.timeout, 1); ++ if (ret) ++ return dev_err_probe(dev, ret, "Failed to set timeout\n"); ++ ++ return devm_watchdog_register_device(dev, &ctrl->wdev); ++} ++ ++static const struct of_device_id otto_wdt_ids[] = { ++ { .compatible = "realtek,rtl8380-wdt" }, ++ { .compatible = "realtek,rtl8390-wdt" }, ++ { .compatible = "realtek,rtl9300-wdt" }, ++ { } ++}; ++MODULE_DEVICE_TABLE(of, otto_wdt_ids); ++ ++static struct platform_driver otto_wdt_driver = { ++ .probe = otto_wdt_probe, ++ .driver = { ++ .name = "realtek-otto-watchdog", ++ .of_match_table = otto_wdt_ids, ++ }, ++}; ++module_platform_driver(otto_wdt_driver); ++ ++MODULE_LICENSE("GPL v2"); ++MODULE_AUTHOR("Sander Vanheule "); ++MODULE_DESCRIPTION("Realtek Otto watchdog timer driver"); +-- +2.31.1 + diff --git a/target/linux/realtek/patches-5.10/307-wdt-update-dependency-for-realtek-otto-wdt.patch b/target/linux/realtek/patches-5.10/307-wdt-update-dependency-for-realtek-otto-wdt.patch new file mode 100644 index 0000000000..32c3e2bb69 --- /dev/null +++ b/target/linux/realtek/patches-5.10/307-wdt-update-dependency-for-realtek-otto-wdt.patch @@ -0,0 +1,17 @@ +Index: linux-5.10.76/drivers/watchdog/Kconfig +=================================================================== +--- linux-5.10.76.orig/drivers/watchdog/Kconfig ++++ linux-5.10.76/drivers/watchdog/Kconfig +@@ -997,10 +997,10 @@ config RTD119X_WATCHDOG + + config REALTEK_OTTO_WDT + tristate "Realtek Otto MIPS watchdog support" +- depends on MACH_REALTEK_RTL || COMPILE_TEST ++ depends on RTL838X + depends on COMMON_CLK + select WATCHDOG_CORE +- default MACH_REALTEK_RTL ++ default RTL838X + help + Say Y here to include support for the watchdog timer on Realtek + RTL838x, RTL839x, RTL930x SoCs. This watchdog has pretimeout diff --git a/target/linux/realtek/patches-5.10/308-otto-wdt-fix-missing-math-header.patch b/target/linux/realtek/patches-5.10/308-otto-wdt-fix-missing-math-header.patch new file mode 100644 index 0000000000..20f86ed7e2 --- /dev/null +++ b/target/linux/realtek/patches-5.10/308-otto-wdt-fix-missing-math-header.patch @@ -0,0 +1,13 @@ +Index: linux-5.10.72/drivers/watchdog/realtek_otto_wdt.c +=================================================================== +--- linux-5.10.72.orig/drivers/watchdog/realtek_otto_wdt.c ++++ linux-5.10.72/drivers/watchdog/realtek_otto_wdt.c +@@ -21,7 +21,7 @@ + #include + #include + #include +-#include ++#include + #include + #include + #include