linux/arch/frv/kernel/sysctl.c

222 lines
4.4 KiB
C

/* 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(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(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);