diff options
Diffstat (limited to 'arch/frv/kernel/sysctl.c')
| -rw-r--r-- | arch/frv/kernel/sysctl.c | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/arch/frv/kernel/sysctl.c b/arch/frv/kernel/sysctl.c new file mode 100644 index 000000000..f4dfae2c7 --- /dev/null +++ b/arch/frv/kernel/sysctl.c @@ -0,0 +1,221 @@ +/* sysctl.c: implementation of /proc/sys files relating to FRV specifically + * + * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * 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. + */ + +#include <linux/sysctl.h> +#include <linux/proc_fs.h> +#include <linux/init.h> +#include <asm/uaccess.h> + +static const char frv_cache_wback[] = "wback"; +static const char frv_cache_wthru[] = "wthru"; + +static void frv_change_dcache_mode(unsigned long newmode) +{ + unsigned long flags, hsr0; + + local_irq_save(flags); + + hsr0 = __get_HSR(0); + hsr0 &= ~HSR0_DCE; + __set_HSR(0, hsr0); + + asm volatile(" dcef @(gr0,gr0),#1 \n" + " membar \n" + : : : "memory" + ); + + hsr0 = (hsr0 & ~HSR0_CBM) | newmode; + __set_HSR(0, hsr0); + hsr0 |= HSR0_DCE; + __set_HSR(0, hsr0); + + local_irq_restore(flags); + + //printk("HSR0 now %08lx\n", hsr0); +} + +/*****************************************************************************/ +/* + * handle requests to dynamically switch the write caching mode delivered by /proc + */ +static int procctl_frv_cachemode(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, + loff_t *ppos) +{ + unsigned long hsr0; + char buff[8]; + int len; + + len = *lenp; + + if (write) { + /* potential state change */ + if (len <= 1 || len > sizeof(buff) - 1) + return -EINVAL; + + if (copy_from_user(buff, buffer, len) != 0) + return -EFAULT; + + if (buff[len - 1] == '\n') + buff[len - 1] = '\0'; + else + buff[len] = '\0'; + + if (strcmp(buff, frv_cache_wback) == 0) { + /* switch dcache into write-back mode */ + frv_change_dcache_mode(HSR0_CBM_COPY_BACK); + return 0; + } + + if (strcmp(buff, frv_cache_wthru) == 0) { + /* switch dcache into write-through mode */ + frv_change_dcache_mode(HSR0_CBM_WRITE_THRU); + return 0; + } + + return -EINVAL; + } + + /* read the state */ + if (*ppos > 0) { + *lenp = 0; + return 0; + } + + hsr0 = __get_HSR(0); + switch (hsr0 & HSR0_CBM) { + case HSR0_CBM_WRITE_THRU: + memcpy(buff, frv_cache_wthru, sizeof(frv_cache_wthru) - 1); + buff[sizeof(frv_cache_wthru) - 1] = '\n'; + len = sizeof(frv_cache_wthru); + break; + default: + memcpy(buff, frv_cache_wback, sizeof(frv_cache_wback) - 1); + buff[sizeof(frv_cache_wback) - 1] = '\n'; + len = sizeof(frv_cache_wback); + break; + } + + if (len > *lenp) + len = *lenp; + + if (copy_to_user(buffer, buff, len) != 0) + return -EFAULT; + + *lenp = len; + *ppos = len; + return 0; + +} /* end procctl_frv_cachemode() */ + +/*****************************************************************************/ +/* + * permit the mm_struct the nominated process is using have its MMU context ID pinned + */ +#ifdef CONFIG_MMU +static int procctl_frv_pin_cxnr(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, + loff_t *ppos) +{ + pid_t pid; + char buff[16], *p; + int len; + + len = *lenp; + + if (write) { + /* potential state change */ + if (len <= 1 || len > sizeof(buff) - 1) + return -EINVAL; + + if (copy_from_user(buff, buffer, len) != 0) + return -EFAULT; + + if (buff[len - 1] == '\n') + buff[len - 1] = '\0'; + else + buff[len] = '\0'; + + pid = simple_strtoul(buff, &p, 10); + if (*p) + return -EINVAL; + + return cxn_pin_by_pid(pid); + } + + /* read the currently pinned CXN */ + if (*ppos > 0) { + *lenp = 0; + return 0; + } + + len = snprintf(buff, sizeof(buff), "%d\n", cxn_pinned); + if (len > *lenp) + len = *lenp; + + if (copy_to_user(buffer, buff, len) != 0) + return -EFAULT; + + *lenp = len; + *ppos = len; + return 0; + +} /* end procctl_frv_pin_cxnr() */ +#endif + +/* + * FR-V specific sysctls + */ +static struct ctl_table frv_table[] = +{ + { + .procname = "cache-mode", + .data = NULL, + .maxlen = 0, + .mode = 0644, + .proc_handler = procctl_frv_cachemode, + }, +#ifdef CONFIG_MMU + { + .procname = "pin-cxnr", + .data = NULL, + .maxlen = 0, + .mode = 0644, + .proc_handler = procctl_frv_pin_cxnr + }, +#endif + {} +}; + +/* + * Use a temporary sysctl number. Horrid, but will be cleaned up in 2.6 + * when all the PM interfaces exist nicely. + */ +static struct ctl_table frv_dir_table[] = +{ + { + .procname = "frv", + .mode = 0555, + .child = frv_table + }, + {} +}; + +/* + * Initialize power interface + */ +static int __init frv_sysctl_init(void) +{ + register_sysctl_table(frv_dir_table); + return 0; +} + +__initcall(frv_sysctl_init); |