2 * wARM - exporting ARM processor specific privileged services to userspace
5 * Author: GraÅžvydas "notaz" Ignotas
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
12 #include <linux/module.h>
13 #include <linux/kernel.h>
14 #include <linux/proc_fs.h>
15 #include <linux/delay.h>
17 #include <linux/seq_file.h>
19 #include <linux/version.h>
20 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,11)
21 #include <linux/uaccess.h>
23 #include <linux/init.h>
24 #include <linux/moduleparam.h>
25 #include <asm/uaccess.h>
27 #define unlocked_ioctl ioctl
34 #ifndef CONFIG_PROC_FS
41 #define WARM_INFO(fmt, ...) \
43 pr_info(PFX fmt, ##__VA_ARGS__)
45 #define MAX_CACHEOP_RANGE 16384
47 /* assume RAM starts at phys addr 0 (this is really machine specific) */
48 #define RAM_PHYS_START 0
49 #define RAM_MAX_SIZE 0x10000000 /* 256M, try to be future proof */
52 #if defined(CONFIG_CPU_ARM926T)
53 #define EXPECTED_ID 0x069260
54 #elif defined(CONFIG_CPU_ARM920T)
55 #define EXPECTED_ID 0x029200
57 #error "unsupported CPU"
60 extern unsigned long max_mapnr;
62 /* "upper" physical memory, not seen by Linux and to be mmap'ed */
63 static u32 uppermem_start;
64 static u32 uppermem_end;
68 static u32 *get_pgtable(void)
72 /* get the pointer to the translation table base... */
73 asm ("mrc p15, 0, %0, c2, c0, 0" : "=r"(ttb));
75 return __va((ttb) & 0xffffc000);
78 static int do_set_cb_uppermem(int in_cb, int is_set)
84 if (uppermem_end <= uppermem_start)
87 if (in_cb & WCB_C_BIT)
89 if (in_cb & WCB_B_BIT)
92 pgtable = get_pgtable();
94 for (i = 0; i < 4096; i++)
96 if ((pgtable[i] & 3) != 1)
97 /* must be coarse page table */
100 cpt = __va(pgtable[i] & 0xfffffc00);
102 for (j = 0; j < 256; j++)
111 addr = entry & 0xfffff000;
112 if (uppermem_start <= addr && addr < uppermem_end)
114 pr_debug(PFX "%s C&B bits %08x\n",
115 is_set ? "set" : "clear", entry);
122 /* need to also set AP bits (so that no faults
123 * happen and kernel doesn't touch this after us) */
124 if ((entry & 3) == 3)
125 entry |= 0x030; /* tiny page */
136 warm_drain_wb_inval_tlb();
138 WARM_INFO("%c%c bit(s) %s for phys %08x-%08x (%d pages)\n",
139 bits & 8 ? 'c' : ' ', bits & 4 ? 'b' : ' ',
140 is_set ? "set" : "cleared",
141 uppermem_start, uppermem_end - 1, count);
146 static int do_set_cb_virt(int in_cb, int is_set, u32 addr, u32 size)
148 int count = 0, bits = 0;
154 if (in_cb & WCB_C_BIT)
156 if (in_cb & WCB_B_BIT)
159 mask = PAGE_SIZE - 1;
161 size = (size + mask) & ~mask;
163 addr &= ~(PAGE_SIZE - 1);
167 pgtable = get_pgtable();
169 for (; addr < end; addr += PAGE_SIZE)
171 desc1 = pgtable[addr >> 20];
173 if ((desc1 & 3) != 1) {
174 printk(KERN_WARNING PFX "not coarse table? %08x %08x\n", desc1, addr);
178 cpt = __va(desc1 & 0xfffffc00);
179 desc2 = cpt[(addr >> 12) & 0xff];
181 if ((desc2 & 3) != 2) {
182 printk(KERN_WARNING PFX "not small page? %08x %08x\n", desc2, addr);
192 cpt[(addr >> 12) & 0xff] = desc2;
197 warm_drain_wb_inval_tlb();
199 WARM_INFO("%c%c bit(s) %s virt %08x-%08x (%d pages)\n",
200 bits & 8 ? 'c' : ' ', bits & 4 ? 'b' : ' ',
201 is_set ? "set" : "cleared", start, end - 1, count);
206 static int do_virt2phys(unsigned long *_addr)
212 pgtable = get_pgtable();
213 desc1 = pgtable[addr >> 20];
216 case 1: /* coarse table */
217 cpt = __va(desc1 & 0xfffffc00);
218 desc2 = cpt[(addr >> 12) & 0xff];
220 case 2: /* 1MB section */
221 *_addr = (desc1 & 0xfff00000) | (addr & 0xfffff);
223 case 3: /* fine table */
224 cpt = __va(desc1 & 0xfffff000);
225 desc2 = cpt[(addr >> 10) & 0x3ff];
233 case 1: /* large page */
234 *_addr = (desc2 & ~0xffff) | (addr & 0xffff);
236 case 2: /* small page */
237 *_addr = (desc2 & ~0x0fff) | (addr & 0x0fff);
239 case 3: /* tiny page */
240 *_addr = (desc2 & ~0x03ff) | (addr & 0x03ff);
249 static int do_cache_ops_whole(int ops)
251 if ((ops & (WOP_D_CLEAN|WOP_D_INVALIDATE)) == (WOP_D_CLEAN|WOP_D_INVALIDATE))
252 warm_cop_clean_inval_d();
254 else if (ops & WOP_D_CLEAN)
257 else if (ops & WOP_D_INVALIDATE) {
258 printk(KERN_WARNING PFX "invalidate without clean is dangerous!\n");
262 if (ops & WOP_I_INVALIDATE)
269 static int do_cache_ops(int ops, u32 addr, u32 size)
277 case WOP_D_CLEAN|WOP_D_INVALIDATE|WOP_I_INVALIDATE:
278 warm_cop_r_clean_d_inval_di(addr, size);
280 case WOP_D_CLEAN|WOP_D_INVALIDATE:
281 warm_cop_r_clean_d_inval_d(addr, size);
283 case WOP_D_CLEAN|WOP_I_INVALIDATE:
284 warm_cop_r_clean_d_inval_i(addr, size);
287 warm_cop_r_clean_d(addr, size);
289 case WOP_D_INVALIDATE|WOP_I_INVALIDATE:
290 warm_cop_r_inval_di(addr, size);
292 case WOP_D_INVALIDATE:
293 warm_cop_r_inval_d(addr, size);
295 case WOP_I_INVALIDATE:
296 warm_cop_r_inval_i(addr, size);
307 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,11)
308 static long warm_ioctl(struct file *file, unsigned int cmd, unsigned long __arg)
310 static int warm_ioctl(struct inode *inode, struct file *file,
311 unsigned int cmd, unsigned long __arg)
314 void __user *arg = (void __user *) __arg;
316 struct warm_cache_op wcop;
317 struct warm_change_cb ccb;
324 if (copy_from_user(&u.wcop, arg, sizeof(u.wcop)))
326 if (u.wcop.ops & ~(WOP_D_CLEAN|WOP_D_INVALIDATE|WOP_I_INVALIDATE))
328 if (u.wcop.size == (unsigned long)-1 ||
329 (u.wcop.size > MAX_CACHEOP_RANGE && !(u.wcop.ops & WOP_D_INVALIDATE)))
330 ret = do_cache_ops_whole(u.wcop.ops);
332 ret = do_cache_ops(u.wcop.ops, u.wcop.addr, u.wcop.size);
334 case WARMC_CHANGE_CB:
335 if (copy_from_user(&u.ccb, arg, sizeof(u.ccb)))
337 if (u.ccb.cb & ~(WCB_C_BIT|WCB_B_BIT))
339 if (u.ccb.addr == 0 && u.ccb.size == 0)
340 ret = do_set_cb_uppermem(u.ccb.cb, u.ccb.is_set);
342 ret = do_set_cb_virt(u.ccb.cb, u.ccb.is_set, u.ccb.addr, u.ccb.size);
344 case WARMC_VIRT2PHYS:
345 if (copy_from_user(&u.addr, arg, sizeof(u.addr)))
347 ret = do_virt2phys(&u.addr);
348 if (copy_to_user(arg, &u.addr, sizeof(u.addr)))
359 static const char *warm_implementor_name(char code)
369 return "Motorola - Freescale";
376 static const char *warm_arch_name(int code)
397 static int warm_cache_size(int code, int m)
405 static int warm_cache_assoc(int code, int m)
412 return base << (code - 1);
415 static int warm_cache_line(int code)
420 static int warm_seq_show(struct seq_file *seq, void *offset)
424 seq_printf(seq, "wARM: " WARM_VER "\n");
427 asm ("mrc p15, 0, %0, c0, c0, 0" : "=r"(tmp));
428 seq_printf(seq, "ID: %08x\n", tmp);
430 /* revised format, not yet documented */
431 } else if ((tmp & 0xf000) == 0) {
433 seq_printf(seq, "Architecture: %d\n",
434 (tmp & 0xf00) == 0x600 ? 3 : 2);
435 seq_printf(seq, "Variant: %d%d0\n", (tmp & 0xf00) >> 8,
438 seq_printf(seq, "Implementor: %c (%s)\n", tmp >> 24,
439 warm_implementor_name(tmp >> 24));
440 if ((tmp & 0xf000) == 7) {
441 seq_printf(seq, "Architecture: %s\n",
442 tmp & 0x800000 ? "4T" : "3");
443 seq_printf(seq, "Variant: 0x%x\n", (tmp & 0x7f0000) >> 16);
445 seq_printf(seq, "Architecture: %s\n",
446 warm_arch_name((tmp & 0x0f0000) >> 16));
447 seq_printf(seq, "Variant: 0x%x\n", (tmp & 0xf00000) >> 20);
449 seq_printf(seq, "Part number: 0x%x\n", (tmp & 0xfff0) >> 4);
451 seq_printf(seq, "Revision: 0x%x\n", tmp & 0xf);
454 asm ("mrc p15, 0, %0, c0, c0, 1" : "=r"(tmp));
455 seq_printf(seq, "Cache ctype: 0x%x\n", (tmp & 0x1e000000) >> 25);
456 seq_printf(seq, "Cache unified: %s\n", (tmp & 0x01000000) ? "no" : "yes");
457 seq_printf(seq, "DCache size: %d\n",
458 warm_cache_size((tmp >> (6+12)) & 0xf, (tmp >> (2+12)) & 1));
459 seq_printf(seq, "DCache associativity: %d\n",
460 warm_cache_assoc((tmp >> (3+12)) & 7, (tmp >> (2+12)) & 1));
461 seq_printf(seq, "DCache line size: %d\n",
462 warm_cache_line((tmp >> (0+12)) & 3));
463 seq_printf(seq, "ICache size: %d\n",
464 warm_cache_size((tmp >> 6) & 0xf, (tmp >> 2) & 1));
465 seq_printf(seq, "ICache associativity: %d\n",
466 warm_cache_assoc((tmp >> 3) & 7, (tmp >> 2) & 1));
467 seq_printf(seq, "ICache line size: %d\n",
468 warm_cache_line((tmp >> 0) & 3));
473 static int warm_open(struct inode *inode, struct file *file)
475 return single_open(file, warm_seq_show, NULL);
478 static int warm_close(struct inode *ino, struct file *file)
480 return single_release(ino, file);
483 static const struct file_operations warm_fops = {
484 .owner = THIS_MODULE,
488 .unlocked_ioctl = warm_ioctl,
489 .release = warm_close,
492 static int __init warm_module_init(void)
494 struct proc_dir_entry *pret;
497 asm ("mrc p15, 0, %0, c0, c0, 0" : "=r"(cpuid));
498 if ((cpuid & 0x0ffff0) != EXPECTED_ID) {
499 printk(KERN_ERR PFX "module was compiled for different CPU, aborting\n");
503 pret = create_proc_entry("warm", S_IWUGO | S_IRUGO, NULL);
505 printk(KERN_ERR PFX "can't create proc entry\n");
509 pret->owner = THIS_MODULE;
510 pret->proc_fops = &warm_fops;
512 uppermem_start = RAM_PHYS_START + (max_mapnr << PAGE_SHIFT);
513 uppermem_end = RAM_PHYS_START + RAM_MAX_SIZE;
515 pr_info(PFX WARM_VER " loaded, ");
516 if (uppermem_end <= uppermem_start)
517 printk("no upper mem");
519 printk("upper mem %08x-%08x", uppermem_start, uppermem_end - 1);
522 /* give time for /proc node to appear */
528 static void __exit warm_module_exit(void)
530 remove_proc_entry("warm", NULL);
532 pr_info(PFX "unloaded.\n");
535 module_init(warm_module_init);
536 module_exit(warm_module_exit);
538 module_param(verbose, int, 0644);
540 MODULE_LICENSE("GPL");
541 MODULE_DESCRIPTION("ARM processor services");
542 MODULE_AUTHOR("Grazvydas Ignotas");