/* * Copyright (C) 2015 Broadcom Corporation * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #include #include #include #include #include #include #include #include #define WDT_START_1 0xff00 #define WDT_START_2 0x00ff #define WDT_STOP_1 0xee00 #define WDT_STOP_2 0x00ee #define WDT_TIMEOUT_REG 0x0 #define WDT_CMD_REG 0x4 #define WDT_MIN_TIMEOUT 1 /* seconds */ #define WDT_DEFAULT_TIMEOUT 30 /* seconds */ #define WDT_DEFAULT_RATE 27000000 struct bcm7038_watchdog { void __iomem *base; struct watchdog_device wdd; u32 rate; struct clk *clk; }; static bool nowayout = WATCHDOG_NOWAYOUT; static void bcm7038_wdt_set_timeout_reg(struct watchdog_device *wdog) { struct bcm7038_watchdog *wdt = watchdog_get_drvdata(wdog); u32 timeout; timeout = wdt->rate * wdog->timeout; writel(timeout, wdt->base + WDT_TIMEOUT_REG); } static int bcm7038_wdt_ping(struct watchdog_device *wdog) { struct bcm7038_watchdog *wdt = watchdog_get_drvdata(wdog); writel(WDT_START_1, wdt->base + WDT_CMD_REG); writel(WDT_START_2, wdt->base + WDT_CMD_REG); return 0; } static int bcm7038_wdt_start(struct watchdog_device *wdog) { bcm7038_wdt_set_timeout_reg(wdog); bcm7038_wdt_ping(wdog); return 0; } static int bcm7038_wdt_stop(struct watchdog_device *wdog) { struct bcm7038_watchdog *wdt = watchdog_get_drvdata(wdog); writel(WDT_STOP_1, wdt->base + WDT_CMD_REG); writel(WDT_STOP_2, wdt->base + WDT_CMD_REG); return 0; } static int bcm7038_wdt_set_timeout(struct watchdog_device *wdog, unsigned int t) { /* Can't modify timeout value if watchdog timer is running */ bcm7038_wdt_stop(wdog); wdog->timeout = t; bcm7038_wdt_start(wdog); return 0; } static unsigned int bcm7038_wdt_get_timeleft(struct watchdog_device *wdog) { struct bcm7038_watchdog *wdt = watchdog_get_drvdata(wdog); u32 time_left; time_left = readl(wdt->base + WDT_CMD_REG); return time_left / wdt->rate; } static struct watchdog_info bcm7038_wdt_info = { .identity = "Broadcom BCM7038 Watchdog Timer", .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE }; static const struct watchdog_ops bcm7038_wdt_ops = { .owner = THIS_MODULE, .start = bcm7038_wdt_start, .stop = bcm7038_wdt_stop, .set_timeout = bcm7038_wdt_set_timeout, .get_timeleft = bcm7038_wdt_get_timeleft, }; static int bcm7038_wdt_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct bcm7038_watchdog *wdt; struct resource *res; int err; wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL); if (!wdt) return -ENOMEM; platform_set_drvdata(pdev, wdt); res = platform_get_resource(pdev, IORESOURCE_MEM, 0); wdt->base = devm_ioremap_resource(dev, res); if (IS_ERR(wdt->base)) return PTR_ERR(wdt->base); wdt->clk = devm_clk_get(dev, NULL); /* If unable to get clock, use default frequency */ if (!IS_ERR(wdt->clk)) { clk_prepare_enable(wdt->clk); wdt->rate = clk_get_rate(wdt->clk); /* Prevent divide-by-zero exception */ if (!wdt->rate) wdt->rate = WDT_DEFAULT_RATE; } else { wdt->rate = WDT_DEFAULT_RATE; wdt->clk = NULL; } wdt->wdd.info = &bcm7038_wdt_info; wdt->wdd.ops = &bcm7038_wdt_ops; wdt->wdd.min_timeout = WDT_MIN_TIMEOUT; wdt->wdd.timeout = WDT_DEFAULT_TIMEOUT; wdt->wdd.max_timeout = 0xffffffff / wdt->rate; wdt->wdd.parent = dev; watchdog_set_drvdata(&wdt->wdd, wdt); err = watchdog_register_device(&wdt->wdd); if (err) { dev_err(dev, "Failed to register watchdog device\n"); clk_disable_unprepare(wdt->clk); return err; } dev_info(dev, "Registered BCM7038 Watchdog\n"); return 0; } static int bcm7038_wdt_remove(struct platform_device *pdev) { struct bcm7038_watchdog *wdt = platform_get_drvdata(pdev); if (!nowayout) bcm7038_wdt_stop(&wdt->wdd); watchdog_unregister_device(&wdt->wdd); clk_disable_unprepare(wdt->clk); return 0; } #ifdef CONFIG_PM_SLEEP static int bcm7038_wdt_suspend(struct device *dev) { struct bcm7038_watchdog *wdt = dev_get_drvdata(dev); if (watchdog_active(&wdt->wdd)) return bcm7038_wdt_stop(&wdt->wdd); return 0; } static int bcm7038_wdt_resume(struct device *dev) { struct bcm7038_watchdog *wdt = dev_get_drvdata(dev); if (watchdog_active(&wdt->wdd)) return bcm7038_wdt_start(&wdt->wdd); return 0; } #endif static SIMPLE_DEV_PM_OPS(bcm7038_wdt_pm_ops, bcm7038_wdt_suspend, bcm7038_wdt_resume); static void bcm7038_wdt_shutdown(struct platform_device *pdev) { struct bcm7038_watchdog *wdt = platform_get_drvdata(pdev); if (watchdog_active(&wdt->wdd)) bcm7038_wdt_stop(&wdt->wdd); } static const struct of_device_id bcm7038_wdt_match[] = { { .compatible = "brcm,bcm7038-wdt" }, {}, }; MODULE_DEVICE_TABLE(of, bcm7038_wdt_match); static struct platform_driver bcm7038_wdt_driver = { .probe = bcm7038_wdt_probe, .remove = bcm7038_wdt_remove, .shutdown = bcm7038_wdt_shutdown, .driver = { .name = "bcm7038-wdt", .of_match_table = bcm7038_wdt_match, .pm = &bcm7038_wdt_pm_ops, } }; module_platform_driver(bcm7038_wdt_driver); module_param(nowayout, bool, 0); MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); MODULE_LICENSE("GPL v2"); MODULE_DESCRIPTION("Driver for Broadcom 7038 SoCs Watchdog"); MODULE_AUTHOR("Justin Chen"); 203c302d496d8ee91 (diff)
powerpc/mm: Fix spurrious segfaults on radix with autonuma
When autonuma (Automatic NUMA balancing) marks a PTE inaccessible it clears all the protection bits but leave the PTE valid. With the Radix MMU, an attempt at executing from such a PTE will take a fault with bit 35 of SRR1 set "SRR1_ISI_N_OR_G". It is thus incorrect to treat all such faults as errors. We should pass them to handle_mm_fault() for autonuma to deal with. The case of pages that are really not executable is handled by the existing test for VM_EXEC further down. That leaves us with catching the kernel attempts at executing user pages. We can catch that earlier, even before we do find_vma. It is never valid on powerpc for the kernel to take an exec fault to begin with. So fold that test with the existing test for the kernel faulting on kernel addresses to bail out early. Fixes: 1d18ad026844 ("powerpc/mm: Detect instruction fetch denied and report") Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'include/keys')