/* * MOXA ART SoCs watchdog driver. * * Copyright (C) 2013 Jonas Jensen * * Jonas Jensen * * This file is licensed under the terms of the GNU General Public * License version 2. This program is licensed "as is" without any * warranty of any kind, whether express or implied. */ #include #include #include #include #include #include #include #include #define REG_COUNT 0x4 #define REG_MODE 0x8 #define REG_ENABLE 0xC struct moxart_wdt_dev { struct watchdog_device dev; void __iomem *base; unsigned int clock_frequency; }; static int heartbeat; static int moxart_wdt_restart(struct watchdog_device *wdt_dev, unsigned long action, void *data) { struct moxart_wdt_dev *moxart_wdt = watchdog_get_drvdata(wdt_dev); writel(1, moxart_wdt->base + REG_COUNT); writel(0x5ab9, moxart_wdt->base + REG_MODE); writel(0x03, moxart_wdt->base + REG_ENABLE); return 0; } static int moxart_wdt_stop(struct watchdog_device *wdt_dev) { struct moxart_wdt_dev *moxart_wdt = watchdog_get_drvdata(wdt_dev); writel(0, moxart_wdt->base + REG_ENABLE); return 0; } static int moxart_wdt_start(struct watchdog_device *wdt_dev) { struct moxart_wdt_dev *moxart_wdt = watchdog_get_drvdata(wdt_dev); writel(moxart_wdt->clock_frequency * wdt_dev->timeout, moxart_wdt->base + REG_COUNT); writel(0x5ab9, moxart_wdt->base + REG_MODE); writel(0x03, moxart_wdt->base + REG_ENABLE); return 0; } static int moxart_wdt_set_timeout(struct watchdog_device *wdt_dev, unsigned int timeout) { wdt_dev->timeout = timeout; return 0; } static const struct watchdog_info moxart_wdt_info = { .identity = "moxart-wdt", .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, }; static const struct watchdog_ops moxart_wdt_ops = { .owner = THIS_MODULE, .start = moxart_wdt_start, .stop = moxart_wdt_stop, .set_timeout = moxart_wdt_set_timeout, .restart = moxart_wdt_restart, }; static int moxart_wdt_probe(struct platform_device *pdev) { struct moxart_wdt_dev *moxart_wdt; struct device *dev = &pdev->dev; struct device_node *node = dev->of_node; struct resource *res; struct clk *clk; int err; unsigned int max_timeout; bool nowayout = WATCHDOG_NOWAYOUT; moxart_wdt = devm_kzalloc(dev, sizeof(*moxart_wdt), GFP_KERNEL); if (!moxart_wdt) return -ENOMEM; platform_set_drvdata(pdev, moxart_wdt); res = platform_get_resource(pdev, IORESOURCE_MEM, 0); moxart_wdt->base = devm_ioremap_resource(dev, res); if (IS_ERR(moxart_wdt->base)) return PTR_ERR(moxart_wdt->base); clk = of_clk_get(node, 0); if (IS_ERR(clk)) { pr_err("%s: of_clk_get failed\n", __func__); return PTR_ERR(clk); } moxart_wdt->clock_frequency = clk_get_rate(clk); if (moxart_wdt->clock_frequency == 0) { pr_err("%s: incorrect clock frequency\n", __func__); return -EINVAL; } max_timeout = UINT_MAX / moxart_wdt->clock_frequency; moxart_wdt->dev.info = &moxart_wdt_info; moxart_wdt->dev.ops = &moxart_wdt_ops; moxart_wdt->dev.timeout = max_timeout; moxart_wdt->dev.min_timeout = 1; moxart_wdt->dev.max_timeout = max_timeout; moxart_wdt->dev.parent = dev; watchdog_init_timeout(&moxart_wdt->dev, heartbeat, dev); watchdog_set_nowayout(&moxart_wdt->dev, nowayout); watchdog_set_restart_priority(&moxart_wdt->dev, 128); watchdog_set_drvdata(&moxart_wdt->dev, moxart_wdt); err = watchdog_register_device(&moxart_wdt->dev); if (err) return err; dev_dbg(dev, "Watchdog enabled (heartbeat=%d sec, nowayout=%d)\n", moxart_wdt->dev.timeout, nowayout); return 0; } static int moxart_wdt_remove(struct platform_device *pdev) { struct moxart_wdt_dev *moxart_wdt = platform_get_drvdata(pdev); moxart_wdt_stop(&moxart_wdt->dev); return 0; } static const struct of_device_id moxart_watchdog_match[] = { { .compatible = "moxa,moxart-watchdog" }, { }, }; MODULE_DEVICE_TABLE(of, moxart_watchdog_match); static struct platform_driver moxart_wdt_driver = { .probe = moxart_wdt_probe, .remove = moxart_wdt_remove, .driver = { .name = "moxart-watchdog", .of_match_table = moxart_watchdog_match, }, }; module_platform_driver(moxart_wdt_driver); module_param(heartbeat, int, 0); MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds"); MODULE_DESCRIPTION("MOXART watchdog driver"); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Jonas Jensen "); t();'>mode:
authorArd Biesheuvel <ard.biesheuvel@linaro.org>2017-02-01 17:45:02 +0000
committerIngo Molnar <mingo@kernel.org>2017-02-01 21:17:49 +0100
commitc8f325a59cfc718d13a50fbc746ed9b415c25e92 (patch)
treed53fbdac9d0781e39a13b2ac6b2bd258cf3b4140 /sound/pci/oxygen/cs4398.h
parentbf29bddf0417a4783da3b24e8c9e017ac649326f (diff)
efi/fdt: Avoid FDT manipulation after ExitBootServices()
Some AArch64 UEFI implementations disable the MMU in ExitBootServices(), after which unaligned accesses to RAM are no longer supported. Commit: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel") fixed an issue in the memory map handling of the stub FDT code, but inadvertently created an issue with such firmware, by moving some of the FDT manipulation to after the invocation of ExitBootServices(). Given that the stub's libfdt implementation uses the ordinary, accelerated string functions, which rely on hardware handling of unaligned accesses, manipulating the FDT with the MMU off may result in alignment faults. So fix the situation by moving the update_fdt_memmap() call into the callback function invoked by efi_exit_boot_services() right before it calls the ExitBootServices() UEFI service (which is arguably a better place for it anyway) Note that disabling the MMU in ExitBootServices() is not compliant with the UEFI spec, and carries great risk due to the fact that switching from cached to uncached memory accesses halfway through compiler generated code (i.e., involving a stack) can never be done in a way that is architecturally safe. Fixes: abfb7b686a3e ("efi/libstub/arm*: Pass latest memory map to the kernel") Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Tested-by: Riku Voipio <riku.voipio@linaro.org> Cc: <stable@vger.kernel.org> Cc: mark.rutland@arm.com Cc: linux-efi@vger.kernel.org Cc: matt@codeblueprint.co.uk Cc: leif.lindholm@linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1485971102-23330-2-git-send-email-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'sound/pci/oxygen/cs4398.h')