/* * sp5100_tco : TCO timer driver for sp5100 chipsets * * (c) Copyright 2009 Google Inc., All Rights Reserved. * * Based on i8xx_tco.c: * (c) Copyright 2000 kernel concepts , All Rights * Reserved. * http://www.kernelconcepts.de * * 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. * * See AMD Publication 43009 "AMD SB700/710/750 Register Reference Guide", * AMD Publication 45482 "AMD SB800-Series Southbridges Register * Reference Guide" */ /* * Includes, defines, variables, module parameters, ... */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include #include #include #include #include #include #include "sp5100_tco.h" #define TCO_DRIVER_NAME "sp5100-tco" /* internal variables */ struct sp5100_tco { struct watchdog_device wdd; void __iomem *tcobase; }; /* the watchdog platform device */ static struct platform_device *sp5100_tco_platform_device; /* the associated PCI device */ static struct pci_dev *sp5100_tco_pci; /* module parameters */ #define WATCHDOG_HEARTBEAT 60 /* 60 sec default heartbeat. */ static int heartbeat = WATCHDOG_HEARTBEAT; /* in seconds */ module_param(heartbeat, int, 0); MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. (default=" __MODULE_STRING(WATCHDOG_HEARTBEAT) ")"); static bool nowayout = WATCHDOG_NOWAYOUT; module_param(nowayout, bool, 0); MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started." " (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); /* * Some TCO specific functions */ static bool tco_has_sp5100_reg_layout(struct pci_dev *dev) { return dev->device == PCI_DEVICE_ID_ATI_SBX00_SMBUS && dev->revision < 0x40; } static int tco_timer_start(struct watchdog_device *wdd) { struct sp5100_tco *tco = watchdog_get_drvdata(wdd); u32 val; val = readl(SP5100_WDT_CONTROL(tco->tcobase)); val |= SP5100_WDT_START_STOP_BIT; writel(val, SP5100_WDT_CONTROL(tco->tcobase)); return 0; } static int tco_timer_stop(struct watchdog_device *wdd) { struct sp5100_tco *tco = watchdog_get_drvdata(wdd); u32 val; val = readl(SP5100_WDT_CONTROL(tco->tcobase)); val &= ~SP5100_WDT_START_STOP_BIT; writel(val, SP5100_WDT_CONTROL(tco->tcobase)); return 0; } static int tco_timer_ping(struct watchdog_device *wdd) { struct sp5100_tco *tco = watchdog_get_drvdata(wdd); u32 val; val = readl(SP5100_WDT_CONTROL(tco->tcobase)); val |= SP5100_WDT_TRIGGER_BIT; writel(val, SP5100_WDT_CONTROL(tco->tcobase)); return 0; } static int tco_timer_set_timeout(struct watchdog_device *wdd, unsigned int t) { struct sp5100_tco *tco = watchdog_get_drvdata(wdd); /* Write new heartbeat to watchdog */ writel(t, SP5100_WDT_COUNT(tco->tcobase)); wdd->timeout = t; return 0; } static u8 sp5100_tco_read_pm_reg8(u8 index) { outb(index, SP5100_IO_PM_INDEX_REG); return inb(SP5100_IO_PM_DATA_REG); } static void sp5100_tco_update_pm_reg8(u8 index, u8 reset, u8 set) { u8 val; outb(index, SP5100_IO_PM_INDEX_REG); val = inb(SP5100_IO_PM_DATA_REG); val &= reset; val |= set; outb(val, SP5100_IO_PM_DATA_REG); } static void tco_timer_enable(void) { if (!tco_has_sp5100_reg_layout(sp5100_tco_pci)) { /* For SB800 or later */ /* Set the Watchdog timer resolution to 1 sec */ sp5100_tco_update_pm_reg8(SB800_PM_WATCHDOG_CONFIG, 0xff, SB800_PM_WATCHDOG_SECOND_RES); /* Enable watchdog decode bit and watchdog timer */ sp5100_tco_update_pm_reg8(SB800_PM_WATCHDOG_CONTROL, ~SB800_PM_WATCHDOG_DISABLE, SB800_PCI_WATCHDOG_DECODE_EN); } else { u32 val; /* For SP5100 or SB7x0 */ /* Enable watchdog decode bit */ pci_read_config_dword(sp5100_tco_pci, SP5100_PCI_WATCHDOG_MISC_REG, &val); val |= SP5100_PCI_WATCHDOG_DECODE_EN; pci_write_config_dword(sp5100_tco_pci, SP5100_PCI_WATCHDOG_MISC_REG, val); /* Enable Watchdog timer and set the resolution to 1 sec */ sp5100_tco_update_pm_reg8(SP5100_PM_WATCHDOG_CONTROL, ~SP5100_PM_WATCHDOG_DISABLE, SP5100_PM_WATCHDOG_SECOND_RES); } } static u32 sp5100_tco_read_pm_reg32(u8 index) { u32 val = 0; int i; for (i = 3; i >= 0; i--) val = (val << 8) + sp5100_tco_read_pm_reg8(index + i); return val; } static int sp5100_tco_setupdevice(struct device *dev, struct watchdog_device *wdd) { struct sp5100_tco *tco = watchdog_get_drvdata(wdd); const char *dev_name; u8 base_addr; u32 val; int ret; /* * Determine type of southbridge chipset. */ if (tco_has_sp5100_reg_layout(sp5100_tco_pci)) { dev_name = SP5100_DEVNAME; base_addr = SP5100_PM_WATCHDOG_BASE; } else { dev_name = SB800_DEVNAME; base_addr = SB800_PM_WATCHDOG_BASE; } /* Request the IO ports used by this driver */ if (!request_muxed_region(SP5100_IO_PM_INDEX_REG, SP5100_PM_IOPORTS_SIZE, dev_name)) { dev_err(dev, "I/O address 0x%04x already in use\n", SP5100_IO_PM_INDEX_REG); return -EBUSY; } /* * First, Find the watchdog timer MMIO address from indirect I/O. * Low three bits of BASE are reserved. */ val = sp5100_tco_read_pm_reg32(base_addr) & 0xfffffff8; dev_dbg(dev, "Got 0x%04x from indirect I/O\n", val); /* Check MMIO address conflict */ if (!devm_request_mem_region(dev, val, SP5100_WDT_MEM_MAP_SIZE, dev_name)) { dev_dbg(dev, "MMIO address 0x%04x already in use\n", val); /* * Secondly, Find the watchdog timer MMIO address * from SBResource_MMIO register. */ if (tco_has_sp5100_reg_layout(sp5100_tco_pci)) { /* Read SBResource_MMIO from PCI config(PCI_Reg: 9Ch) */ pci_read_config_dword(sp5100_tco_pci, SP5100_SB_RESOURCE_MMIO_BASE, &val); } else { /* Read SBResource_MMIO from AcpiMmioEn(PM_Reg: 24h) */ val = sp5100_tco_read_pm_reg32(SB800_PM_ACPI_MMIO_EN); } /* The SBResource_MMIO is enabled and mapped memory space? */ if ((val & (SB800_ACPI_MMIO_DECODE_EN | SB800_ACPI_MMIO_SEL)) != SB800_ACPI_MMIO_DECODE_EN) { dev_notice(dev, "failed to find MMIO address, giving up.\n"); ret = -ENODEV; goto unreg_region; } /* Clear unnecessary the low twelve bits */ val &= ~0xFFF; /* Add the Watchdog Timer offset to base address. */ val += SB800_PM_WDT_MMIO_OFFSET; /* Check MMIO address conflict */ if (!devm_request_mem_region(dev, val, SP5100_WDT_MEM_MAP_SIZE, dev_name)) { dev_dbg(dev, "MMIO address 0x%04x already in use\n", val); ret = -EBUSY; goto unreg_region; } dev_dbg(dev, "Got 0x%04x from SBResource_MMIO register\n", val); } tco->tcobase = devm_ioremap(dev, val, SP5100_WDT_MEM_MAP_SIZE); if (!tco->tcobase) { dev_err(dev, "failed to get tcobase address\n"); ret = -ENOMEM; goto unreg_region; } dev_info(dev, "Using 0x%04x for watchdog MMIO address\n", val); /* Setup the watchdog timer */ tco_timer_enable(); /* Check that the watchdog action is set to reset the system */ val = readl(SP5100_WDT_CONTROL(tco->tcobase)); /* * Save WatchDogFired status, because WatchDogFired flag is * cleared here. */ if (val & SP5100_WDT_FIRED) wdd->bootstatus = WDIOF_CARDRESET; val &= ~SP5100_WDT_ACTION_RESET; writel(val, SP5100_WDT_CONTROL(tco->tcobase)); /* Set a reasonable heartbeat before we stop the timer */ tco_timer_set_timeout(wdd, wdd->timeout); /* * Stop the TCO before we change anything so we don't race with * a zeroed timer. */ tco_timer_stop(wdd); release_region(SP5100_IO_PM_INDEX_REG, SP5100_PM_IOPORTS_SIZE); return 0; unreg_region: release_region(SP5100_IO_PM_INDEX_REG, SP5100_PM_IOPORTS_SIZE); return ret; } static struct watchdog_info sp5100_tco_wdt_info = { .identity = "SP5100 TCO timer", .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, }; static const struct watchdog_ops sp5100_tco_wdt_ops = { .owner = THIS_MODULE, .start = tco_timer_start, .stop = tco_timer_stop, .ping = tco_timer_ping, .set_timeout = tco_timer_set_timeout, }; static int sp5100_tco_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct watchdog_device *wdd; struct sp5100_tco *tco; int ret; tco = devm_kzalloc(dev, sizeof(*tco), GFP_KERNEL); if (!tco) return -ENOMEM; wdd = &tco->wdd; wdd->parent = dev; wdd->info = &sp5100_tco_wdt_info; wdd->ops = &sp5100_tco_wdt_ops; wdd->timeout = WATCHDOG_HEARTBEAT; wdd->min_timeout = 1; wdd->max_timeout = 0xffff; if (watchdog_init_timeout(wdd, heartbeat, NULL)) dev_info(dev, "timeout value invalid, using %d\n", wdd->timeout); watchdog_set_nowayout(wdd, nowayout); watchdog_stop_on_reboot(wdd); watchdog_stop_on_unregister(wdd); watchdog_set_drvdata(wdd, tco); ret = sp5100_tco_setupdevice(dev, wdd); if (ret) return ret; ret = devm_watchdog_register_device(dev, wdd); if (ret) { dev_err(dev, "cannot register watchdog device (err=%d)\n", ret); return ret; } /* Show module parameters */ dev_info(dev, "initialized. heartbeat=%d sec (nowayout=%d)\n", wdd->timeout, nowayout); return 0; } static struct platform_driver sp5100_tco_driver = { .probe = sp5100_tco_probe, .driver = { .name = TCO_DRIVER_NAME, }, }; /* * Data for PCI driver interface * * This data only exists for exporting the supported * PCI ids via MODULE_DEVICE_TABLE. We do not actually * register a pci_driver, because someone else might * want to register another driver on the same PCI id. */ static const struct pci_device_id sp5100_tco_pci_tbl[] = { { PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_SBX00_SMBUS, PCI_ANY_ID, PCI_ANY_ID, }, { PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_HUDSON2_SMBUS, PCI_ANY_ID, PCI_ANY_ID, }, { PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_KERNCZ_SMBUS, PCI_ANY_ID, PCI_ANY_ID, }, { 0, }, /* End of list */ }; MODULE_DEVICE_TABLE(pci, sp5100_tco_pci_tbl); static int __init sp5100_tco_init(void) { struct pci_dev *dev = NULL; int err; /* Match the PCI device */ for_each_pci_dev(dev) { if (pci_match_id(sp5100_tco_pci_tbl, dev) != NULL) { sp5100_tco_pci = dev; break; } } if (!sp5100_tco_pci) return -ENODEV; pr_info("SP5100/SB800 TCO WatchDog Timer Driver\n"); err = platform_driver_register(&sp5100_tco_driver); if (err) return err; sp5100_tco_platform_device = platform_device_register_simple(TCO_DRIVER_NAME, -1, NULL, 0); if (IS_ERR(sp5100_tco_platform_device)) { err = PTR_ERR(sp5100_tco_platform_device); goto unreg_platform_driver; } return 0; unreg_platform_driver: platform_driver_unregister(&sp5100_tco_driver); return err; } static void __exit sp5100_tco_exit(void) { platform_device_unregister(sp5100_tco_platform_device); platform_driver_unregister(&sp5100_tco_driver); } module_init(sp5100_tco_init); module_exit(sp5100_tco_exit); MODULE_AUTHOR("Priyanka Gupta"); MODULE_DESCRIPTION("TCO timer driver for SP5100/SB800 chipset"); MODULE_LICENSE("GPL");