]>
Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* sysctl.c: implementation of /proc/sys files relating to FRV specifically |
2 | * | |
3 | * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. | |
4 | * Written by David Howells (dhowells@redhat.com) | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public License | |
8 | * as published by the Free Software Foundation; either version | |
9 | * 2 of the License, or (at your option) any later version. | |
10 | */ | |
11 | ||
12 | #include <linux/config.h> | |
13 | #include <linux/slab.h> | |
14 | #include <linux/sysctl.h> | |
15 | #include <linux/proc_fs.h> | |
16 | #include <linux/init.h> | |
17 | #include <asm/uaccess.h> | |
18 | ||
19 | static const char frv_cache_wback[] = "wback"; | |
20 | static const char frv_cache_wthru[] = "wthru"; | |
21 | ||
22 | static void frv_change_dcache_mode(unsigned long newmode) | |
23 | { | |
24 | unsigned long flags, hsr0; | |
25 | ||
26 | local_irq_save(flags); | |
27 | ||
28 | hsr0 = __get_HSR(0); | |
29 | hsr0 &= ~HSR0_DCE; | |
30 | __set_HSR(0, hsr0); | |
31 | ||
32 | asm volatile(" dcef @(gr0,gr0),#1 \n" | |
33 | " membar \n" | |
34 | : : : "memory" | |
35 | ); | |
36 | ||
37 | hsr0 = (hsr0 & ~HSR0_CBM) | newmode; | |
38 | __set_HSR(0, hsr0); | |
39 | hsr0 |= HSR0_DCE; | |
40 | __set_HSR(0, hsr0); | |
41 | ||
42 | local_irq_restore(flags); | |
43 | ||
44 | //printk("HSR0 now %08lx\n", hsr0); | |
45 | } | |
46 | ||
47 | /*****************************************************************************/ | |
48 | /* | |
49 | * handle requests to dynamically switch the write caching mode delivered by /proc | |
50 | */ | |
51 | static int procctl_frv_cachemode(ctl_table *table, int write, struct file *filp, | |
52 | void *buffer, size_t *lenp, loff_t *ppos) | |
53 | { | |
54 | unsigned long hsr0; | |
55 | char buff[8]; | |
56 | int len; | |
57 | ||
58 | len = *lenp; | |
59 | ||
60 | if (write) { | |
61 | /* potential state change */ | |
62 | if (len <= 1 || len > sizeof(buff) - 1) | |
63 | return -EINVAL; | |
64 | ||
65 | if (copy_from_user(buff, buffer, len) != 0) | |
66 | return -EFAULT; | |
67 | ||
68 | if (buff[len - 1] == '\n') | |
69 | buff[len - 1] = '\0'; | |
70 | else | |
71 | buff[len] = '\0'; | |
72 | ||
73 | if (strcmp(buff, frv_cache_wback) == 0) { | |
74 | /* switch dcache into write-back mode */ | |
75 | frv_change_dcache_mode(HSR0_CBM_COPY_BACK); | |
76 | return 0; | |
77 | } | |
78 | ||
79 | if (strcmp(buff, frv_cache_wthru) == 0) { | |
80 | /* switch dcache into write-through mode */ | |
81 | frv_change_dcache_mode(HSR0_CBM_WRITE_THRU); | |
82 | return 0; | |
83 | } | |
84 | ||
85 | return -EINVAL; | |
86 | } | |
87 | ||
88 | /* read the state */ | |
89 | if (filp->f_pos > 0) { | |
90 | *lenp = 0; | |
91 | return 0; | |
92 | } | |
93 | ||
94 | hsr0 = __get_HSR(0); | |
95 | switch (hsr0 & HSR0_CBM) { | |
96 | case HSR0_CBM_WRITE_THRU: | |
97 | memcpy(buff, frv_cache_wthru, sizeof(frv_cache_wthru) - 1); | |
98 | buff[sizeof(frv_cache_wthru) - 1] = '\n'; | |
99 | len = sizeof(frv_cache_wthru); | |
100 | break; | |
101 | default: | |
102 | memcpy(buff, frv_cache_wback, sizeof(frv_cache_wback) - 1); | |
103 | buff[sizeof(frv_cache_wback) - 1] = '\n'; | |
104 | len = sizeof(frv_cache_wback); | |
105 | break; | |
106 | } | |
107 | ||
108 | if (len > *lenp) | |
109 | len = *lenp; | |
110 | ||
111 | if (copy_to_user(buffer, buff, len) != 0) | |
112 | return -EFAULT; | |
113 | ||
114 | *lenp = len; | |
115 | filp->f_pos = len; | |
116 | return 0; | |
117 | ||
118 | } /* end procctl_frv_cachemode() */ | |
119 | ||
120 | /*****************************************************************************/ | |
121 | /* | |
122 | * permit the mm_struct the nominated process is using have its MMU context ID pinned | |
123 | */ | |
124 | #ifdef CONFIG_MMU | |
125 | static int procctl_frv_pin_cxnr(ctl_table *table, int write, struct file *filp, | |
126 | void *buffer, size_t *lenp, loff_t *ppos) | |
127 | { | |
128 | pid_t pid; | |
129 | char buff[16], *p; | |
130 | int len; | |
131 | ||
132 | len = *lenp; | |
133 | ||
134 | if (write) { | |
135 | /* potential state change */ | |
136 | if (len <= 1 || len > sizeof(buff) - 1) | |
137 | return -EINVAL; | |
138 | ||
139 | if (copy_from_user(buff, buffer, len) != 0) | |
140 | return -EFAULT; | |
141 | ||
142 | if (buff[len - 1] == '\n') | |
143 | buff[len - 1] = '\0'; | |
144 | else | |
145 | buff[len] = '\0'; | |
146 | ||
147 | pid = simple_strtoul(buff, &p, 10); | |
148 | if (*p) | |
149 | return -EINVAL; | |
150 | ||
151 | return cxn_pin_by_pid(pid); | |
152 | } | |
153 | ||
154 | /* read the currently pinned CXN */ | |
155 | if (filp->f_pos > 0) { | |
156 | *lenp = 0; | |
157 | return 0; | |
158 | } | |
159 | ||
160 | len = snprintf(buff, sizeof(buff), "%d\n", cxn_pinned); | |
161 | if (len > *lenp) | |
162 | len = *lenp; | |
163 | ||
164 | if (copy_to_user(buffer, buff, len) != 0) | |
165 | return -EFAULT; | |
166 | ||
167 | *lenp = len; | |
168 | filp->f_pos = len; | |
169 | return 0; | |
170 | ||
171 | } /* end procctl_frv_pin_cxnr() */ | |
172 | #endif | |
173 | ||
174 | /* | |
175 | * FR-V specific sysctls | |
176 | */ | |
177 | static struct ctl_table frv_table[] = | |
178 | { | |
179 | { 1, "cache-mode", NULL, 0, 0644, NULL, &procctl_frv_cachemode }, | |
180 | #ifdef CONFIG_MMU | |
181 | { 2, "pin-cxnr", NULL, 0, 0644, NULL, &procctl_frv_pin_cxnr }, | |
182 | #endif | |
183 | { 0 } | |
184 | }; | |
185 | ||
186 | /* | |
187 | * Use a temporary sysctl number. Horrid, but will be cleaned up in 2.6 | |
188 | * when all the PM interfaces exist nicely. | |
189 | */ | |
190 | #define CTL_FRV 9898 | |
191 | static struct ctl_table frv_dir_table[] = | |
192 | { | |
193 | {CTL_FRV, "frv", NULL, 0, 0555, frv_table}, | |
194 | {0} | |
195 | }; | |
196 | ||
197 | /* | |
198 | * Initialize power interface | |
199 | */ | |
200 | static int __init frv_sysctl_init(void) | |
201 | { | |
202 | register_sysctl_table(frv_dir_table, 1); | |
203 | return 0; | |
204 | } | |
205 | ||
206 | __initcall(frv_sysctl_init); |