4 * Privileged Space Mapping Buffer (PMB) Support.
6 * Copyright (C) 2005, 2006, 2007 Paul Mundt
8 * P1/P2 Section mapping definitions from map32.h, which was:
10 * Copyright 2003 (c) Lineo Solutions,Inc.
12 * This file is subject to the terms and conditions of the GNU General Public
13 * License. See the file "COPYING" in the main directory of this archive
16 #include <linux/init.h>
17 #include <linux/kernel.h>
18 #include <linux/sysdev.h>
19 #include <linux/cpu.h>
20 #include <linux/module.h>
21 #include <linux/slab.h>
22 #include <linux/bitops.h>
23 #include <linux/debugfs.h>
25 #include <linux/seq_file.h>
26 #include <linux/err.h>
27 #include <asm/system.h>
28 #include <asm/uaccess.h>
29 #include <asm/pgtable.h>
32 #include <asm/mmu_context.h>
34 #define NR_PMB_ENTRIES 16
36 static void __pmb_unmap(struct pmb_entry *);
38 static struct kmem_cache *pmb_cache;
39 static unsigned long pmb_map;
41 static struct pmb_entry pmb_init_map[] = {
42 /* vpn ppn flags (ub/sz/c/wt) */
44 /* P1 Section Mappings */
45 { 0x80000000, 0x00000000, PMB_SZ_64M | PMB_C, },
46 { 0x84000000, 0x04000000, PMB_SZ_64M | PMB_C, },
47 { 0x88000000, 0x08000000, PMB_SZ_128M | PMB_C, },
48 { 0x90000000, 0x10000000, PMB_SZ_64M | PMB_C, },
49 { 0x94000000, 0x14000000, PMB_SZ_64M | PMB_C, },
50 { 0x98000000, 0x18000000, PMB_SZ_64M | PMB_C, },
52 /* P2 Section Mappings */
53 { 0xa0000000, 0x00000000, PMB_UB | PMB_SZ_64M | PMB_WT, },
54 { 0xa4000000, 0x04000000, PMB_UB | PMB_SZ_64M | PMB_WT, },
55 { 0xa8000000, 0x08000000, PMB_UB | PMB_SZ_128M | PMB_WT, },
56 { 0xb0000000, 0x10000000, PMB_UB | PMB_SZ_64M | PMB_WT, },
57 { 0xb4000000, 0x14000000, PMB_UB | PMB_SZ_64M | PMB_WT, },
58 { 0xb8000000, 0x18000000, PMB_UB | PMB_SZ_64M | PMB_WT, },
61 static inline unsigned long mk_pmb_entry(unsigned int entry)
63 return (entry & PMB_E_MASK) << PMB_E_SHIFT;
66 static inline unsigned long mk_pmb_addr(unsigned int entry)
68 return mk_pmb_entry(entry) | PMB_ADDR;
71 static inline unsigned long mk_pmb_data(unsigned int entry)
73 return mk_pmb_entry(entry) | PMB_DATA;
76 static DEFINE_SPINLOCK(pmb_list_lock);
77 static struct pmb_entry *pmb_list;
79 static inline void pmb_list_add(struct pmb_entry *pmbe)
81 struct pmb_entry **p, *tmp;
84 while ((tmp = *p) != NULL)
91 static inline void pmb_list_del(struct pmb_entry *pmbe)
93 struct pmb_entry **p, *tmp;
95 for (p = &pmb_list; (tmp = *p); p = &tmp->next)
102 struct pmb_entry *pmb_alloc(unsigned long vpn, unsigned long ppn,
105 struct pmb_entry *pmbe;
107 pmbe = kmem_cache_alloc(pmb_cache, GFP_KERNEL);
109 return ERR_PTR(-ENOMEM);
115 spin_lock_irq(&pmb_list_lock);
117 spin_unlock_irq(&pmb_list_lock);
122 void pmb_free(struct pmb_entry *pmbe)
124 spin_lock_irq(&pmb_list_lock);
126 spin_unlock_irq(&pmb_list_lock);
128 kmem_cache_free(pmb_cache, pmbe);
132 * Must be in P2 for __set_pmb_entry()
134 int __set_pmb_entry(unsigned long vpn, unsigned long ppn,
135 unsigned long flags, int *entry)
137 unsigned int pos = *entry;
139 if (unlikely(pos == PMB_NO_ENTRY))
140 pos = find_first_zero_bit(&pmb_map, NR_PMB_ENTRIES);
143 if (unlikely(pos > NR_PMB_ENTRIES))
146 if (test_and_set_bit(pos, &pmb_map)) {
147 pos = find_first_zero_bit(&pmb_map, NR_PMB_ENTRIES);
151 ctrl_outl(vpn | PMB_V, mk_pmb_addr(pos));
153 #ifdef CONFIG_CACHE_WRITETHROUGH
155 * When we are in 32-bit address extended mode, CCR.CB becomes
156 * invalid, so care must be taken to manually adjust cacheable
159 if (likely(flags & PMB_C))
163 ctrl_outl(ppn | flags | PMB_V, mk_pmb_data(pos));
170 int __uses_jump_to_uncached set_pmb_entry(struct pmb_entry *pmbe)
175 ret = __set_pmb_entry(pmbe->vpn, pmbe->ppn, pmbe->flags, &pmbe->entry);
181 void __uses_jump_to_uncached clear_pmb_entry(struct pmb_entry *pmbe)
183 unsigned int entry = pmbe->entry;
187 * Don't allow clearing of wired init entries, P1 or P2 access
188 * without a corresponding mapping in the PMB will lead to reset
191 if (unlikely(entry < ARRAY_SIZE(pmb_init_map) ||
192 entry >= NR_PMB_ENTRIES))
198 addr = mk_pmb_addr(entry);
199 ctrl_outl(ctrl_inl(addr) & ~PMB_V, addr);
201 addr = mk_pmb_data(entry);
202 ctrl_outl(ctrl_inl(addr) & ~PMB_V, addr);
206 clear_bit(entry, &pmb_map);
214 { .size = 0x20000000, .flag = PMB_SZ_512M, },
215 { .size = 0x08000000, .flag = PMB_SZ_128M, },
216 { .size = 0x04000000, .flag = PMB_SZ_64M, },
217 { .size = 0x01000000, .flag = PMB_SZ_16M, },
220 long pmb_remap(unsigned long vaddr, unsigned long phys,
221 unsigned long size, unsigned long flags)
223 struct pmb_entry *pmbp, *pmbe;
224 unsigned long wanted;
228 /* Convert typical pgprot value to the PMB equivalent */
229 if (flags & _PAGE_CACHABLE) {
230 if (flags & _PAGE_WT)
235 pmb_flags = PMB_WT | PMB_UB;
241 for (i = 0; i < ARRAY_SIZE(pmb_sizes); i++) {
244 if (size < pmb_sizes[i].size)
247 pmbe = pmb_alloc(vaddr, phys, pmb_flags | pmb_sizes[i].flag);
253 ret = set_pmb_entry(pmbe);
260 phys += pmb_sizes[i].size;
261 vaddr += pmb_sizes[i].size;
262 size -= pmb_sizes[i].size;
265 * Link adjacent entries that span multiple PMB entries
266 * for easier tear-down.
274 * Instead of trying smaller sizes on every iteration
275 * (even if we succeed in allocating space), try using
276 * pmb_sizes[i].size again.
281 if (size >= 0x1000000)
284 return wanted - size;
293 void pmb_unmap(unsigned long addr)
295 struct pmb_entry **p, *pmbe;
297 for (p = &pmb_list; (pmbe = *p); p = &pmbe->next)
298 if (pmbe->vpn == addr)
307 static void __pmb_unmap(struct pmb_entry *pmbe)
309 WARN_ON(!test_bit(pmbe->entry, &pmb_map));
312 struct pmb_entry *pmblink = pmbe;
314 if (pmbe->entry != PMB_NO_ENTRY)
315 clear_pmb_entry(pmbe);
317 pmbe = pmblink->link;
323 static void pmb_cache_ctor(void *pmb)
325 struct pmb_entry *pmbe = pmb;
327 memset(pmb, 0, sizeof(struct pmb_entry));
329 pmbe->entry = PMB_NO_ENTRY;
332 static int __uses_jump_to_uncached pmb_init(void)
334 unsigned int nr_entries = ARRAY_SIZE(pmb_init_map);
335 unsigned int entry, i;
337 BUG_ON(unlikely(nr_entries >= NR_PMB_ENTRIES));
339 pmb_cache = kmem_cache_create("pmb", sizeof(struct pmb_entry), 0,
340 SLAB_PANIC, pmb_cache_ctor);
345 * Ordering is important, P2 must be mapped in the PMB before we
346 * can set PMB.SE, and P1 must be mapped before we jump back to
349 for (entry = 0; entry < nr_entries; entry++) {
350 struct pmb_entry *pmbe = pmb_init_map + entry;
352 __set_pmb_entry(pmbe->vpn, pmbe->ppn, pmbe->flags, &entry);
355 ctrl_outl(0, PMB_IRMCR);
357 /* PMB.SE and UB[7] */
358 ctrl_outl((1 << 31) | (1 << 7), PMB_PASCR);
360 /* Flush out the TLB */
369 arch_initcall(pmb_init);
371 static int pmb_seq_show(struct seq_file *file, void *iter)
375 seq_printf(file, "V: Valid, C: Cacheable, WT: Write-Through\n"
376 "CB: Copy-Back, B: Buffered, UB: Unbuffered\n");
377 seq_printf(file, "ety vpn ppn size flags\n");
379 for (i = 0; i < NR_PMB_ENTRIES; i++) {
380 unsigned long addr, data;
384 addr = ctrl_inl(mk_pmb_addr(i));
385 data = ctrl_inl(mk_pmb_data(i));
387 size = data & PMB_SZ_MASK;
388 sz_str = (size == PMB_SZ_16M) ? " 16MB":
389 (size == PMB_SZ_64M) ? " 64MB":
390 (size == PMB_SZ_128M) ? "128MB":
393 /* 02: V 0x88 0x08 128MB C CB B */
394 seq_printf(file, "%02d: %c 0x%02lx 0x%02lx %s %c %s %s\n",
395 i, ((addr & PMB_V) && (data & PMB_V)) ? 'V' : ' ',
396 (addr >> 24) & 0xff, (data >> 24) & 0xff,
397 sz_str, (data & PMB_C) ? 'C' : ' ',
398 (data & PMB_WT) ? "WT" : "CB",
399 (data & PMB_UB) ? "UB" : " B");
405 static int pmb_debugfs_open(struct inode *inode, struct file *file)
407 return single_open(file, pmb_seq_show, NULL);
410 static const struct file_operations pmb_debugfs_fops = {
411 .owner = THIS_MODULE,
412 .open = pmb_debugfs_open,
415 .release = single_release,
418 static int __init pmb_debugfs_init(void)
420 struct dentry *dentry;
422 dentry = debugfs_create_file("pmb", S_IFREG | S_IRUGO,
423 sh_debugfs_root, NULL, &pmb_debugfs_fops);
427 return PTR_ERR(dentry);
431 postcore_initcall(pmb_debugfs_init);
434 static int pmb_sysdev_suspend(struct sys_device *dev, pm_message_t state)
436 static pm_message_t prev_state;
438 /* Restore the PMB after a resume from hibernation */
439 if (state.event == PM_EVENT_ON &&
440 prev_state.event == PM_EVENT_FREEZE) {
441 struct pmb_entry *pmbe;
442 spin_lock_irq(&pmb_list_lock);
443 for (pmbe = pmb_list; pmbe; pmbe = pmbe->next)
445 spin_unlock_irq(&pmb_list_lock);
451 static int pmb_sysdev_resume(struct sys_device *dev)
453 return pmb_sysdev_suspend(dev, PMSG_ON);
456 static struct sysdev_driver pmb_sysdev_driver = {
457 .suspend = pmb_sysdev_suspend,
458 .resume = pmb_sysdev_resume,
461 static int __init pmb_sysdev_init(void)
463 return sysdev_driver_register(&cpu_sysdev_class, &pmb_sysdev_driver);
466 subsys_initcall(pmb_sysdev_init);