From 70c14ff0e9f5e1f5456587b827620e636ba70a09 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Fri, 20 Jul 2007 02:07:26 +0100 Subject: [PATCH] [ARM] 4495/1: iop: combined watchdog timer driver for iop3xx and iop13xx In order for this driver to be shared across the iop architectures the iop3xx and iop13xx header files are modified to present a common interface for the iop_wdt driver. Details: * iop13xx supports disabling the timer while iop3xx does not. This requires a few 'compatibility' definitions in include/asm-arm/hardware/iop3xx.h to preclude adding #ifdef CONFIG_ARCH_IOP13XX blocks to the driver code. * The heartbeat interval is derived from the internal bus clock rate, so this this patch also exports the tick rate to the iop_wdt driver. Cc: Curt Bruns Cc: Peter Milne Signed-off-by: Dan Williams Acked-by: Wim Van Sebroeck Signed-off-by: Russell King --- arch/arm/plat-iop/time.c | 8 + drivers/char/watchdog/Kconfig | 16 ++ drivers/char/watchdog/Makefile | 1 + drivers/char/watchdog/iop_wdt.c | 262 +++++++++++++++++++++++++++++++++ include/asm-arm/arch-iop13xx/iop13xx.h | 43 ++++++ include/asm-arm/arch-iop13xx/system.h | 34 +---- include/asm-arm/hardware/iop3xx.h | 33 +++++ 7 files changed, 365 insertions(+), 32 deletions(-) create mode 100644 drivers/char/watchdog/iop_wdt.c diff --git a/arch/arm/plat-iop/time.c b/arch/arm/plat-iop/time.c index 100d57ad98e..ba3d21d8fba 100644 --- a/arch/arm/plat-iop/time.c +++ b/arch/arm/plat-iop/time.c @@ -78,6 +78,13 @@ static struct irqaction iop_timer_irq = { .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL, }; +static unsigned long iop_tick_rate; +unsigned long get_iop_tick_rate(void) +{ + return iop_tick_rate; +} +EXPORT_SYMBOL(get_iop_tick_rate); + void __init iop_init_time(unsigned long tick_rate) { u32 timer_ctl; @@ -85,6 +92,7 @@ void __init iop_init_time(unsigned long tick_rate) ticks_per_jiffy = (tick_rate + HZ/2) / HZ; ticks_per_usec = tick_rate / 1000000; next_jiffy_time = 0xffffffff; + iop_tick_rate = tick_rate; timer_ctl = IOP_TMR_EN | IOP_TMR_PRIVILEGED | IOP_TMR_RELOAD | IOP_TMR_RATIO_1_1; diff --git a/drivers/char/watchdog/Kconfig b/drivers/char/watchdog/Kconfig index 2f48ba32996..a4d81cda479 100644 --- a/drivers/char/watchdog/Kconfig +++ b/drivers/char/watchdog/Kconfig @@ -187,6 +187,22 @@ config PNX4008_WATCHDOG Say N if you are unsure. +config IOP_WATCHDOG + tristate "IOP Watchdog" + depends on WATCHDOG && PLAT_IOP + select WATCHDOG_NOWAYOUT if (ARCH_IOP32X || ARCH_IOP33X) + help + Say Y here if to include support for the watchdog timer + in the Intel IOP3XX & IOP13XX I/O Processors. This driver can + be built as a module by choosing M. The module will + be called iop_wdt. + + Note: The IOP13XX watchdog does an Internal Bus Reset which will + affect both cores and the peripherals of the IOP. The ATU-X + and/or ATUe configuration registers will remain intact, but if + operating as an Root Complex and/or Central Resource, the PCI-X + and/or PCIe busses will also be reset. THIS IS A VERY BIG HAMMER. + # AVR32 Architecture config AT32AP700X_WDT diff --git a/drivers/char/watchdog/Makefile b/drivers/char/watchdog/Makefile index 3907ec04a4e..bdb9d5e3bb4 100644 --- a/drivers/char/watchdog/Makefile +++ b/drivers/char/watchdog/Makefile @@ -35,6 +35,7 @@ obj-$(CONFIG_SA1100_WATCHDOG) += sa1100_wdt.o obj-$(CONFIG_MPCORE_WATCHDOG) += mpcore_wdt.o obj-$(CONFIG_EP93XX_WATCHDOG) += ep93xx_wdt.o obj-$(CONFIG_PNX4008_WATCHDOG) += pnx4008_wdt.o +obj-$(CONFIG_IOP_WATCHDOG) += iop_wdt.o # AVR32 Architecture obj-$(CONFIG_AT32AP700X_WDT) += at32ap700x_wdt.o diff --git a/drivers/char/watchdog/iop_wdt.c b/drivers/char/watchdog/iop_wdt.c new file mode 100644 index 00000000000..bbbd91af754 --- /dev/null +++ b/drivers/char/watchdog/iop_wdt.c @@ -0,0 +1,262 @@ +/* + * drivers/char/watchdog/iop_wdt.c + * + * WDT driver for Intel I/O Processors + * Copyright (C) 2005, Intel Corporation. + * + * Based on ixp4xx driver, Copyright 2004 (c) MontaVista, Software, Inc. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope 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. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., 59 Temple + * Place - Suite 330, Boston, MA 02111-1307 USA. + * + * Curt E Bruns + * Peter Milne + * Dan Williams + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +static int nowayout = WATCHDOG_NOWAYOUT; +static unsigned long wdt_status; +static unsigned long boot_status; + +#define WDT_IN_USE 0 +#define WDT_OK_TO_CLOSE 1 +#define WDT_ENABLED 2 + +static unsigned long iop_watchdog_timeout(void) +{ + return (0xffffffffUL / get_iop_tick_rate()); +} + +/** + * wdt_supports_disable - determine if we are accessing a iop13xx watchdog + * or iop3xx by whether it has a disable command + */ +static int wdt_supports_disable(void) +{ + int can_disable; + + if (IOP_WDTCR_EN_ARM != IOP_WDTCR_DIS_ARM) + can_disable = 1; + else + can_disable = 0; + + return can_disable; +} + +static void wdt_enable(void) +{ + /* Arm and enable the Timer to starting counting down from 0xFFFF.FFFF + * Takes approx. 10.7s to timeout + */ + write_wdtcr(IOP_WDTCR_EN_ARM); + write_wdtcr(IOP_WDTCR_EN); +} + +/* returns 0 if the timer was successfully disabled */ +static int wdt_disable(void) +{ + /* Stop Counting */ + if (wdt_supports_disable()) { + write_wdtcr(IOP_WDTCR_DIS_ARM); + write_wdtcr(IOP_WDTCR_DIS); + clear_bit(WDT_ENABLED, &wdt_status); + printk(KERN_INFO "WATCHDOG: Disabled\n"); + return 0; + } else + return 1; +} + +static int iop_wdt_open(struct inode *inode, struct file *file) +{ + if (test_and_set_bit(WDT_IN_USE, &wdt_status)) + return -EBUSY; + + clear_bit(WDT_OK_TO_CLOSE, &wdt_status); + + wdt_enable(); + + set_bit(WDT_ENABLED, &wdt_status); + + return nonseekable_open(inode, file); +} + +static ssize_t +iop_wdt_write(struct file *file, const char *data, size_t len, + loff_t *ppos) +{ + if (len) { + if (!nowayout) { + size_t i; + + clear_bit(WDT_OK_TO_CLOSE, &wdt_status); + + for (i = 0; i != len; i++) { + char c; + + if (get_user(c, data + i)) + return -EFAULT; + if (c == 'V') + set_bit(WDT_OK_TO_CLOSE, &wdt_status); + } + } + wdt_enable(); + } + + return len; +} + +static struct watchdog_info ident = { + .options = WDIOF_CARDRESET | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING, + .identity = "iop watchdog", +}; + +static int +iop_wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, + unsigned long arg) +{ + int options; + int ret = -ENOTTY; + + switch (cmd) { + case WDIOC_GETSUPPORT: + if (copy_to_user + ((struct watchdog_info *)arg, &ident, sizeof ident)) + ret = -EFAULT; + else + ret = 0; + break; + + case WDIOC_GETSTATUS: + ret = put_user(0, (int *)arg); + break; + + case WDIOC_GETBOOTSTATUS: + ret = put_user(boot_status, (int *)arg); + break; + + case WDIOC_GETTIMEOUT: + ret = put_user(iop_watchdog_timeout(), (int *)arg); + break; + + case WDIOC_KEEPALIVE: + wdt_enable(); + ret = 0; + break; + + case WDIOC_SETOPTIONS: + if (get_user(options, (int *)arg)) + return -EFAULT; + + if (options & WDIOS_DISABLECARD) { + if (!nowayout) { + if (wdt_disable() == 0) { + set_bit(WDT_OK_TO_CLOSE, &wdt_status); + ret = 0; + } else + ret = -ENXIO; + } else + ret = 0; + } + + if (options & WDIOS_ENABLECARD) { + wdt_enable(); + ret = 0; + } + break; + } + + return ret; +} + +static int iop_wdt_release(struct inode *inode, struct file *file) +{ + int state = 1; + if (test_bit(WDT_OK_TO_CLOSE, &wdt_status)) + if (test_bit(WDT_ENABLED, &wdt_status)) + state = wdt_disable(); + + /* if the timer is not disbaled reload and notify that we are still + * going down + */ + if (state != 0) { + wdt_enable(); + printk(KERN_CRIT "WATCHDOG: Device closed unexpectedly - " + "reset in %lu seconds\n", iop_watchdog_timeout()); + } + + clear_bit(WDT_IN_USE, &wdt_status); + clear_bit(WDT_OK_TO_CLOSE, &wdt_status); + + return 0; +} + +static const struct file_operations iop_wdt_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .write = iop_wdt_write, + .ioctl = iop_wdt_ioctl, + .open = iop_wdt_open, + .release = iop_wdt_release, +}; + +static struct miscdevice iop_wdt_miscdev = { + .minor = WATCHDOG_MINOR, + .name = "watchdog", + .fops = &iop_wdt_fops, +}; + +static int __init iop_wdt_init(void) +{ + int ret; + + ret = misc_register(&iop_wdt_miscdev); + if (ret == 0) + printk("iop watchdog timer: timeout %lu sec\n", + iop_watchdog_timeout()); + + /* check if the reset was caused by the watchdog timer */ + boot_status = (read_rcsr() & IOP_RCSR_WDT) ? WDIOF_CARDRESET : 0; + + /* Configure Watchdog Timeout to cause an Internal Bus (IB) Reset + * NOTE: An IB Reset will Reset both cores in the IOP342 + */ + write_wdtsr(IOP13XX_WDTCR_IB_RESET); + + return ret; +} + +static void __exit iop_wdt_exit(void) +{ + misc_deregister(&iop_wdt_miscdev); +} + +module_init(iop_wdt_init); +module_exit(iop_wdt_exit); + +module_param(nowayout, int, 0); +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started"); + +MODULE_AUTHOR("Curt E Bruns "); +MODULE_DESCRIPTION("iop watchdog timer driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); diff --git a/include/asm-arm/arch-iop13xx/iop13xx.h b/include/asm-arm/arch-iop13xx/iop13xx.h index d4e4f828577..52b7fab7ef6 100644 --- a/include/asm-arm/arch-iop13xx/iop13xx.h +++ b/include/asm-arm/arch-iop13xx/iop13xx.h @@ -19,6 +19,39 @@ static inline int iop13xx_cpu_id(void) return id; } +/* WDTCR CP6 R7 Page 9 */ +static inline u32 read_wdtcr(void) +{ + u32 val; + asm volatile("mrc p6, 0, %0, c7, c9, 0":"=r" (val)); + return val; +} +static inline void write_wdtcr(u32 val) +{ + asm volatile("mcr p6, 0, %0, c7, c9, 0"::"r" (val)); +} + +/* WDTSR CP6 R8 Page 9 */ +static inline u32 read_wdtsr(void) +{ + u32 val; + asm volatile("mrc p6, 0, %0, c8, c9, 0":"=r" (val)); + return val; +} +static inline void write_wdtsr(u32 val) +{ + asm volatile("mcr p6, 0, %0, c8, c9, 0"::"r" (val)); +} + +/* RCSR - Reset Cause Status Register */ +static inline u32 read_rcsr(void) +{ + u32 val; + asm volatile("mrc p6, 0, %0, c0, c1, 0":"=r" (val)); + return val; +} + +extern unsigned long get_iop_tick_rate(void); #endif /* @@ -480,4 +513,14 @@ static inline int iop13xx_cpu_id(void) #define IOP13XX_PBI_LR1 IOP13XX_PBI_OFFSET(0x14) #define IOP13XX_PROCESSOR_FREQ IOP13XX_REG_ADDR32(0x2180) + +/* Watchdog timer definitions */ +#define IOP_WDTCR_EN_ARM 0x1e1e1e1e +#define IOP_WDTCR_EN 0xe1e1e1e1 +#define IOP_WDTCR_DIS_ARM 0x1f1f1f1f +#define IOP_WDTCR_DIS 0xf1f1f1f1 +#define IOP_RCSR_WDT (1 << 5) /* reset caused by watchdog timer */ +#define IOP13XX_WDTSR_WRITE_EN (1 << 31) /* used to speed up reset requests */ +#define IOP13XX_WDTCR_IB_RESET (1 << 0) + #endif /* _IOP13XX_HW_H_ */ diff --git a/include/asm-arm/arch-iop13xx/system.h b/include/asm-arm/arch-iop13xx/system.h index 127827058e1..8575af8db78 100644 --- a/include/asm-arm/arch-iop13xx/system.h +++ b/include/asm-arm/arch-iop13xx/system.h @@ -13,43 +13,13 @@ static inline void arch_idle(void) cpu_do_idle(); } -/* WDTCR CP6 R7 Page 9 */ -static inline u32 read_wdtcr(void) -{ - u32 val; - asm volatile("mrc p6, 0, %0, c7, c9, 0":"=r" (val)); - return val; -} -static inline void write_wdtcr(u32 val) -{ - asm volatile("mcr p6, 0, %0, c7, c9, 0"::"r" (val)); -} - -/* WDTSR CP6 R8 Page 9 */ -static inline u32 read_wdtsr(void) -{ - u32 val; - asm volatile("mrc p6, 0, %0, c8, c9, 0":"=r" (val)); - return val; -} -static inline void write_wdtsr(u32 val) -{ - asm volatile("mcr p6, 0, %0, c8, c9, 0"::"r" (val)); -} - -#define IOP13XX_WDTCR_EN_ARM 0x1e1e1e1e -#define IOP13XX_WDTCR_EN 0xe1e1e1e1 -#define IOP13XX_WDTCR_DIS_ARM 0x1f1f1f1f -#define IOP13XX_WDTCR_DIS 0xf1f1f1f1 -#define IOP13XX_WDTSR_WRITE_EN (1 << 31) -#define IOP13XX_WDTCR_IB_RESET (1 << 0) static inline void arch_reset(char mode) { /* * Reset the internal bus (warning both cores are reset) */ - write_wdtcr(IOP13XX_WDTCR_EN_ARM); - write_wdtcr(IOP13XX_WDTCR_EN); + write_wdtcr(IOP_WDTCR_EN_ARM); + write_wdtcr(IOP_WDTCR_EN); write_wdtsr(IOP13XX_WDTSR_WRITE_EN | IOP13XX_WDTCR_IB_RESET); write_wdtcr(0x1000); diff --git a/include/asm-arm/hardware/iop3xx.h b/include/asm-arm/hardware/iop3xx.h index 81ca5d3e2bf..fb90b421f31 100644 --- a/include/asm-arm/hardware/iop3xx.h +++ b/include/asm-arm/hardware/iop3xx.h @@ -194,6 +194,13 @@ extern int init_atu; #define IOP_TMR_PRIVILEGED 0x08 #define IOP_TMR_RATIO_1_1 0x00 +/* Watchdog timer definitions */ +#define IOP_WDTCR_EN_ARM 0x1e1e1e1e +#define IOP_WDTCR_EN 0xe1e1e1e1 +/* iop3xx does not support stopping the watchdog, so we just re-arm */ +#define IOP_WDTCR_DIS_ARM (IOP_WDTCR_EN_ARM) +#define IOP_WDTCR_DIS (IOP_WDTCR_EN) + /* Application accelerator unit */ #define IOP3XX_AAU_PHYS_BASE (IOP3XX_PERIPHERAL_PHYS_BASE + 0x800) #define IOP3XX_AAU_UPPER_PA (IOP3XX_AAU_PHYS_BASE + 0xa7) @@ -274,6 +281,32 @@ static inline void write_tisr(u32 val) asm volatile("mcr p6, 0, %0, c6, c1, 0" : : "r" (val)); } +static inline u32 read_wdtcr(void) +{ + u32 val; + asm volatile("mrc p6, 0, %0, c7, c1, 0":"=r" (val)); + return val; +} +static inline void write_wdtcr(u32 val) +{ + asm volatile("mcr p6, 0, %0, c7, c1, 0"::"r" (val)); +} + +extern unsigned long get_iop_tick_rate(void); + +/* only iop13xx has these registers, we define these to present a + * common register interface for the iop_wdt driver. + */ +#define IOP_RCSR_WDT (0) +static inline u32 read_rcsr(void) +{ + return 0; +} +static inline void write_wdtsr(u32 val) +{ + do { } while (0); +} + extern struct platform_device iop3xx_dma_0_channel; extern struct platform_device iop3xx_dma_1_channel; extern struct platform_device iop3xx_aau_channel; -- 2.11.4.GIT