diff options
Diffstat (limited to 'drivers/watchdog/rti_wdt.c')
| -rw-r--r-- | drivers/watchdog/rti_wdt.c | 116 |
1 files changed, 82 insertions, 34 deletions
diff --git a/drivers/watchdog/rti_wdt.c b/drivers/watchdog/rti_wdt.c index 117bc2a8eb0a..be7d7db47591 100644 --- a/drivers/watchdog/rti_wdt.c +++ b/drivers/watchdog/rti_wdt.c @@ -14,6 +14,8 @@ #include <linux/mod_devicetable.h> #include <linux/module.h> #include <linux/moduleparam.h> +#include <linux/of.h> +#include <linux/of_reserved_mem.h> #include <linux/platform_device.h> #include <linux/pm_runtime.h> #include <linux/types.h> @@ -52,7 +54,14 @@ #define DWDST BIT(1) -static int heartbeat = DEFAULT_HEARTBEAT; +#define PON_REASON_SOF_NUM 0xBBBBCCCC +#define PON_REASON_MAGIC_NUM 0xDDDDDDDD +#define PON_REASON_EOF_NUM 0xCCCCBBBB +#define RESERVED_MEM_MIN_SIZE 12 + +#define MAX_HW_ERROR 250 + +static int heartbeat; /* * struct to hold data for each WDT device @@ -70,6 +79,11 @@ static int rti_wdt_start(struct watchdog_device *wdd) { u32 timer_margin; struct rti_wdt_device *wdt = watchdog_get_drvdata(wdd); + int ret; + + ret = pm_runtime_resume_and_get(wdd->parent); + if (ret) + return ret; /* set timeout period */ timer_margin = (u64)wdd->timeout * wdt->freq; @@ -85,7 +99,7 @@ static int rti_wdt_start(struct watchdog_device *wdd) * to be 50% or less than that; we obviouly want to configure the open * window as large as possible so we select the 50% option. */ - wdd->min_hw_heartbeat_ms = 500 * wdd->timeout; + wdd->min_hw_heartbeat_ms = 520 * wdd->timeout + MAX_HW_ERROR; /* Generate NMI when wdt expires */ writel_relaxed(RTIWWDRX_NMI, wdt->base + RTIWWDRXCTRL); @@ -119,31 +133,33 @@ static int rti_wdt_setup_hw_hb(struct watchdog_device *wdd, u32 wsize) * be petted during the open window; not too early or not too late. * The HW configuration options only allow for the open window size * to be 50% or less than that. + * To avoid any glitches, we accommodate 2% + max hardware error + * safety margin. */ switch (wsize) { case RTIWWDSIZE_50P: - /* 50% open window => 50% min heartbeat */ - wdd->min_hw_heartbeat_ms = 500 * heartbeat; + /* 50% open window => 52% min heartbeat */ + wdd->min_hw_heartbeat_ms = 520 * heartbeat + MAX_HW_ERROR; break; case RTIWWDSIZE_25P: - /* 25% open window => 75% min heartbeat */ - wdd->min_hw_heartbeat_ms = 750 * heartbeat; + /* 25% open window => 77% min heartbeat */ + wdd->min_hw_heartbeat_ms = 770 * heartbeat + MAX_HW_ERROR; break; case RTIWWDSIZE_12P5: - /* 12.5% open window => 87.5% min heartbeat */ - wdd->min_hw_heartbeat_ms = 875 * heartbeat; + /* 12.5% open window => 89.5% min heartbeat */ + wdd->min_hw_heartbeat_ms = 895 * heartbeat + MAX_HW_ERROR; break; case RTIWWDSIZE_6P25: - /* 6.5% open window => 93.5% min heartbeat */ - wdd->min_hw_heartbeat_ms = 935 * heartbeat; + /* 6.5% open window => 95.5% min heartbeat */ + wdd->min_hw_heartbeat_ms = 955 * heartbeat + MAX_HW_ERROR; break; case RTIWWDSIZE_3P125: - /* 3.125% open window => 96.9% min heartbeat */ - wdd->min_hw_heartbeat_ms = 969 * heartbeat; + /* 3.125% open window => 98.9% min heartbeat */ + wdd->min_hw_heartbeat_ms = 989 * heartbeat + MAX_HW_ERROR; break; default: @@ -198,6 +214,10 @@ static int rti_wdt_probe(struct platform_device *pdev) struct rti_wdt_device *wdt; struct clk *clk; u32 last_ping = 0; + u32 reserved_mem_size; + struct resource res; + u32 *vaddr; + u64 paddr; wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL); if (!wdt) @@ -216,18 +236,10 @@ static int rti_wdt_probe(struct platform_device *pdev) return -EINVAL; } - /* - * If watchdog is running at 32k clock, it is not accurate. - * Adjust frequency down in this case so that we don't pet - * the watchdog too often. - */ - if (wdt->freq < 32768) - wdt->freq = wdt->freq * 9 / 10; - pm_runtime_enable(dev); - ret = pm_runtime_get_sync(dev); - if (ret) { - pm_runtime_put_noidle(dev); + ret = pm_runtime_resume_and_get(dev); + if (ret < 0) { + pm_runtime_disable(&pdev->dev); return dev_err_probe(dev, ret, "runtime pm failed\n"); } @@ -239,6 +251,7 @@ static int rti_wdt_probe(struct platform_device *pdev) wdd->min_timeout = 1; wdd->max_hw_heartbeat_ms = (WDT_PRELOAD_MAX << WDT_PRELOAD_SHIFT) / wdt->freq * 1000; + wdd->timeout = DEFAULT_HEARTBEAT; wdd->parent = dev; watchdog_set_drvdata(wdd, wdt); @@ -252,21 +265,24 @@ static int rti_wdt_probe(struct platform_device *pdev) } if (readl(wdt->base + RTIDWDCTRL) == WDENABLE_KEY) { + int preset_heartbeat; u32 time_left_ms; u64 heartbeat_ms; u32 wsize; set_bit(WDOG_HW_RUNNING, &wdd->status); time_left_ms = rti_wdt_get_timeleft_ms(wdd); - heartbeat_ms = readl(wdt->base + RTIDWDPRLD); + /* AM62x TRM: texp = (RTIDWDPRLD + 1) * (2^13) / RTICLK1 */ + heartbeat_ms = readl(wdt->base + RTIDWDPRLD) + 1; heartbeat_ms <<= WDT_PRELOAD_SHIFT; heartbeat_ms *= 1000; do_div(heartbeat_ms, wdt->freq); - if (heartbeat_ms != heartbeat * 1000) + preset_heartbeat = heartbeat_ms + 500; + preset_heartbeat /= 1000; + if (preset_heartbeat != heartbeat) dev_warn(dev, "watchdog already running, ignoring heartbeat config!\n"); - heartbeat = heartbeat_ms; - heartbeat /= 1000; + heartbeat = preset_heartbeat; wsize = readl(wdt->base + RTIWWDSIZECTRL); ret = rti_wdt_setup_hw_hb(wdd, wsize); @@ -282,17 +298,48 @@ static int rti_wdt_probe(struct platform_device *pdev) } } + ret = of_reserved_mem_region_to_resource(pdev->dev.of_node, 0, &res); + if (!ret) { + /* + * If reserved memory is defined for watchdog reset cause. + * Readout the Power-on(PON) reason and pass to bootstatus. + */ + paddr = res.start; + reserved_mem_size = resource_size(&res); + if (reserved_mem_size < RESERVED_MEM_MIN_SIZE) { + dev_err(dev, "The size of reserved memory is too small.\n"); + ret = -EINVAL; + goto err_iomap; + } + + vaddr = memremap(paddr, reserved_mem_size, MEMREMAP_WB); + if (!vaddr) { + dev_err(dev, "Failed to map memory-region.\n"); + ret = -ENOMEM; + goto err_iomap; + } + + if (vaddr[0] == PON_REASON_SOF_NUM && + vaddr[1] == PON_REASON_MAGIC_NUM && + vaddr[2] == PON_REASON_EOF_NUM) { + wdd->bootstatus |= WDIOF_CARDRESET; + } + memset(vaddr, 0, reserved_mem_size); + memunmap(vaddr); + } + watchdog_init_timeout(wdd, heartbeat, dev); ret = watchdog_register_device(wdd); - if (ret) { - dev_err(dev, "cannot register watchdog device\n"); + if (ret) goto err_iomap; - } if (last_ping) watchdog_set_last_hw_keepalive(wdd, last_ping); + if (!watchdog_hw_running(wdd)) + pm_runtime_put_sync(&pdev->dev); + return 0; err_iomap: @@ -302,15 +349,16 @@ err_iomap: return ret; } -static int rti_wdt_remove(struct platform_device *pdev) +static void rti_wdt_remove(struct platform_device *pdev) { struct rti_wdt_device *wdt = platform_get_drvdata(pdev); watchdog_unregister_device(&wdt->wdd); - pm_runtime_put(&pdev->dev); - pm_runtime_disable(&pdev->dev); - return 0; + if (!pm_runtime_suspended(&pdev->dev)) + pm_runtime_put(&pdev->dev); + + pm_runtime_disable(&pdev->dev); } static const struct of_device_id rti_wdt_of_match[] = { |