This commit was manufactured by cvs2svn to create branch 'vserver'.

[linux-2.6.git] / arch / frv / kernel / sysctl.c

diff --git a/arch/frv/kernel/sysctl.c b/arch/frv/kernel/sysctl.c
new file mode 100644 (file)
index 0000000..408b0f3
--- /dev/null
+++ b/arch/frv/kernel/sysctl.c
@@ -0,0 +1,206 @@
+/* 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/config.h>
+#include <linux/slab.h>
+#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, struct file *filp,
+                                void *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 (filp->f_pos > 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;
+       filp->f_pos = 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, struct file *filp,
+                               void *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 (filp->f_pos > 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;
+       filp->f_pos = len;
+       return 0;
+
+} /* end procctl_frv_pin_cxnr() */
+#endif
+
+/*
+ * FR-V specific sysctls
+ */
+static struct ctl_table frv_table[] =
+{
+       { 1, "cache-mode",      NULL, 0, 0644, NULL, &procctl_frv_cachemode },
+#ifdef CONFIG_MMU
+       { 2, "pin-cxnr",        NULL, 0, 0644, NULL, &procctl_frv_pin_cxnr },
+#endif
+       { 0 }
+};
+
+/*
+ * Use a temporary sysctl number. Horrid, but will be cleaned up in 2.6
+ * when all the PM interfaces exist nicely.
+ */
+#define CTL_FRV 9898
+static struct ctl_table frv_dir_table[] =
+{
+       {CTL_FRV, "frv", NULL, 0, 0555, frv_table},
+       {0}
+};
+
+/*
+ * Initialize power interface
+ */
+static int __init frv_sysctl_init(void)
+{
+       register_sysctl_table(frv_dir_table, 1);
+       return 0;
+}
+
+__initcall(frv_sysctl_init);