/* 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_MMUstatic 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);