diff options
Diffstat (limited to 'arch/sparc/kernel/apc.c')
| -rw-r--r-- | arch/sparc/kernel/apc.c | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/arch/sparc/kernel/apc.c b/arch/sparc/kernel/apc.c new file mode 100644 index 00000000000..406dd94afb4 --- /dev/null +++ b/arch/sparc/kernel/apc.c @@ -0,0 +1,186 @@ +/* apc - Driver implementation for power management functions + * of Aurora Personality Chip (APC) on SPARCstation-4/5 and + * derivatives. + * + * Copyright (c) 2002 Eric Brower (ebrower@usa.net) + */ + +#include <linux/kernel.h> +#include <linux/fs.h> +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/miscdevice.h> +#include <linux/pm.h> + +#include <asm/io.h> +#include <asm/sbus.h> +#include <asm/oplib.h> +#include <asm/uaccess.h> +#include <asm/auxio.h> +#include <asm/apc.h> + +/* Debugging + * + * #define APC_DEBUG_LED + */ + +#define APC_MINOR MISC_DYNAMIC_MINOR +#define APC_OBPNAME "power-management" +#define APC_DEVNAME "apc" + +volatile static u8 __iomem *regs; +static int apc_regsize; +static int apc_no_idle __initdata = 0; + +#define apc_readb(offs) (sbus_readb(regs+offs)) +#define apc_writeb(val, offs) (sbus_writeb(val, regs+offs)) + +/* Specify "apc=noidle" on the kernel command line to + * disable APC CPU standby support. Certain prototype + * systems (SPARCstation-Fox) do not play well with APC + * CPU idle, so disable this if your system has APC and + * crashes randomly. + */ +static int __init apc_setup(char *str) +{ + if(!strncmp(str, "noidle", strlen("noidle"))) { + apc_no_idle = 1; + return 1; + } + return 0; +} +__setup("apc=", apc_setup); + +/* + * CPU idle callback function + * See .../arch/sparc/kernel/process.c + */ +void apc_swift_idle(void) +{ +#ifdef APC_DEBUG_LED + set_auxio(0x00, AUXIO_LED); +#endif + + apc_writeb(apc_readb(APC_IDLE_REG) | APC_IDLE_ON, APC_IDLE_REG); + +#ifdef APC_DEBUG_LED + set_auxio(AUXIO_LED, 0x00); +#endif +} + +static inline void apc_free(void) +{ + sbus_iounmap(regs, apc_regsize); +} + +static int apc_open(struct inode *inode, struct file *f) +{ + return 0; +} + +static int apc_release(struct inode *inode, struct file *f) +{ + return 0; +} + +static int apc_ioctl(struct inode *inode, struct file *f, + unsigned int cmd, unsigned long __arg) +{ + __u8 inarg, __user *arg; + + arg = (__u8 __user *) __arg; + switch (cmd) { + case APCIOCGFANCTL: + if (put_user(apc_readb(APC_FANCTL_REG) & APC_REGMASK, arg)) + return -EFAULT; + break; + + case APCIOCGCPWR: + if (put_user(apc_readb(APC_CPOWER_REG) & APC_REGMASK, arg)) + return -EFAULT; + break; + + case APCIOCGBPORT: + if (put_user(apc_readb(APC_BPORT_REG) & APC_BPMASK, arg)) + return -EFAULT; + break; + + case APCIOCSFANCTL: + if (get_user(inarg, arg)) + return -EFAULT; + apc_writeb(inarg & APC_REGMASK, APC_FANCTL_REG); + break; + case APCIOCSCPWR: + if (get_user(inarg, arg)) + return -EFAULT; + apc_writeb(inarg & APC_REGMASK, APC_CPOWER_REG); + break; + case APCIOCSBPORT: + if (get_user(inarg, arg)) + return -EFAULT; + apc_writeb(inarg & APC_BPMASK, APC_BPORT_REG); + break; + default: + return -EINVAL; + }; + + return 0; +} + +static struct file_operations apc_fops = { + .ioctl = apc_ioctl, + .open = apc_open, + .release = apc_release, +}; + +static struct miscdevice apc_miscdev = { APC_MINOR, APC_DEVNAME, &apc_fops }; + +static int __init apc_probe(void) +{ + struct sbus_bus *sbus = NULL; + struct sbus_dev *sdev = NULL; + int iTmp = 0; + + for_each_sbus(sbus) { + for_each_sbusdev(sdev, sbus) { + if (!strcmp(sdev->prom_name, APC_OBPNAME)) { + goto sbus_done; + } + } + } + +sbus_done: + if (!sdev) { + return -ENODEV; + } + + apc_regsize = sdev->reg_addrs[0].reg_size; + regs = sbus_ioremap(&sdev->resource[0], 0, + apc_regsize, APC_OBPNAME); + if(!regs) { + printk(KERN_ERR "%s: unable to map registers\n", APC_DEVNAME); + return -ENODEV; + } + + iTmp = misc_register(&apc_miscdev); + if (iTmp != 0) { + printk(KERN_ERR "%s: unable to register device\n", APC_DEVNAME); + apc_free(); + return -ENODEV; + } + + /* Assign power management IDLE handler */ + if(!apc_no_idle) + pm_idle = apc_swift_idle; + + printk(KERN_INFO "%s: power management initialized%s\n", + APC_DEVNAME, apc_no_idle ? " (CPU idle disabled)" : ""); + return 0; +} + +/* This driver is not critical to the boot process + * and is easiest to ioremap when SBus is already + * initialized, so we install ourselves thusly: + */ +__initcall(apc_probe); + |