| /* |
| * arch/sh/mm/pmb.c |
| * |
| * Privileged Space Mapping Buffer (PMB) Support. |
| * |
| * Copyright (C) 2005, 2006, 2007 Paul Mundt |
| * |
| * P1/P2 Section mapping definitions from map32.h, which was: |
| * |
| * Copyright 2003 (c) Lineo Solutions,Inc. |
| * |
| * This file is subject to the terms and conditions of the GNU General Public |
| * License. See the file "COPYING" in the main directory of this archive |
| * for more details. |
| */ |
| #include <linux/init.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/slab.h> |
| #include <linux/bitops.h> |
| #include <linux/debugfs.h> |
| #include <linux/fs.h> |
| #include <linux/seq_file.h> |
| #include <linux/err.h> |
| #include <asm/system.h> |
| #include <asm/uaccess.h> |
| #include <asm/pgtable.h> |
| #include <asm/mmu.h> |
| #include <asm/io.h> |
| #include <asm/mmu_context.h> |
| |
| #define NR_PMB_ENTRIES 16 |
| |
| static struct kmem_cache *pmb_cache; |
| static unsigned long pmb_map; |
| |
| static struct pmb_entry pmb_init_map[] = { |
| /* vpn ppn flags (ub/sz/c/wt) */ |
| |
| /* P1 Section Mappings */ |
| { 0x80000000, 0x00000000, PMB_SZ_64M | PMB_C, }, |
| { 0x84000000, 0x04000000, PMB_SZ_64M | PMB_C, }, |
| { 0x88000000, 0x08000000, PMB_SZ_128M | PMB_C, }, |
| { 0x90000000, 0x10000000, PMB_SZ_64M | PMB_C, }, |
| { 0x94000000, 0x14000000, PMB_SZ_64M | PMB_C, }, |
| { 0x98000000, 0x18000000, PMB_SZ_64M | PMB_C, }, |
| |
| /* P2 Section Mappings */ |
| { 0xa0000000, 0x00000000, PMB_UB | PMB_SZ_64M | PMB_WT, }, |
| { 0xa4000000, 0x04000000, PMB_UB | PMB_SZ_64M | PMB_WT, }, |
| { 0xa8000000, 0x08000000, PMB_UB | PMB_SZ_128M | PMB_WT, }, |
| { 0xb0000000, 0x10000000, PMB_UB | PMB_SZ_64M | PMB_WT, }, |
| { 0xb4000000, 0x14000000, PMB_UB | PMB_SZ_64M | PMB_WT, }, |
| { 0xb8000000, 0x18000000, PMB_UB | PMB_SZ_64M | PMB_WT, }, |
| }; |
| |
| static inline unsigned long mk_pmb_entry(unsigned int entry) |
| { |
| return (entry & PMB_E_MASK) << PMB_E_SHIFT; |
| } |
| |
| static inline unsigned long mk_pmb_addr(unsigned int entry) |
| { |
| return mk_pmb_entry(entry) | PMB_ADDR; |
| } |
| |
| static inline unsigned long mk_pmb_data(unsigned int entry) |
| { |
| return mk_pmb_entry(entry) | PMB_DATA; |
| } |
| |
| static DEFINE_SPINLOCK(pmb_list_lock); |
| static struct pmb_entry *pmb_list; |
| |
| static inline void pmb_list_add(struct pmb_entry *pmbe) |
| { |
| struct pmb_entry **p, *tmp; |
| |
| p = &pmb_list; |
| while ((tmp = *p) != NULL) |
| p = &tmp->next; |
| |
| pmbe->next = tmp; |
| *p = pmbe; |
| } |
| |
| static inline void pmb_list_del(struct pmb_entry *pmbe) |
| { |
| struct pmb_entry **p, *tmp; |
| |
| for (p = &pmb_list; (tmp = *p); p = &tmp->next) |
| if (tmp == pmbe) { |
| *p = tmp->next; |
| return; |
| } |
| } |
| |
| struct pmb_entry *pmb_alloc(unsigned long vpn, unsigned long ppn, |
| unsigned long flags) |
| { |
| struct pmb_entry *pmbe; |
| |
| pmbe = kmem_cache_alloc(pmb_cache, GFP_KERNEL); |
| if (!pmbe) |
| return ERR_PTR(-ENOMEM); |
| |
| pmbe->vpn = vpn; |
| pmbe->ppn = ppn; |
| pmbe->flags = flags; |
| |
| spin_lock_irq(&pmb_list_lock); |
| pmb_list_add(pmbe); |
| spin_unlock_irq(&pmb_list_lock); |
| |
| return pmbe; |
| } |
| |
| void pmb_free(struct pmb_entry *pmbe) |
| { |
| spin_lock_irq(&pmb_list_lock); |
| pmb_list_del(pmbe); |
| spin_unlock_irq(&pmb_list_lock); |
| |
| kmem_cache_free(pmb_cache, pmbe); |
| } |
| |
| /* |
| * Must be in P2 for __set_pmb_entry() |
| */ |
| int __set_pmb_entry(unsigned long vpn, unsigned long ppn, |
| unsigned long flags, int *entry) |
| { |
| unsigned int pos = *entry; |
| |
| if (unlikely(pos == PMB_NO_ENTRY)) |
| pos = find_first_zero_bit(&pmb_map, NR_PMB_ENTRIES); |
| |
| repeat: |
| if (unlikely(pos > NR_PMB_ENTRIES)) |
| return -ENOSPC; |
| |
| if (test_and_set_bit(pos, &pmb_map)) { |
| pos = find_first_zero_bit(&pmb_map, NR_PMB_ENTRIES); |
| goto repeat; |
| } |
| |
| ctrl_outl(vpn | PMB_V, mk_pmb_addr(pos)); |
| |
| #ifdef CONFIG_CACHE_WRITETHROUGH |
| /* |
| * When we are in 32-bit address extended mode, CCR.CB becomes |
| * invalid, so care must be taken to manually adjust cacheable |
| * translations. |
| */ |
| if (likely(flags & PMB_C)) |
| flags |= PMB_WT; |
| #endif |
| |
| ctrl_outl(ppn | flags | PMB_V, mk_pmb_data(pos)); |
| |
| *entry = pos; |
| |
| return 0; |
| } |
| |
| int __uses_jump_to_uncached set_pmb_entry(struct pmb_entry *pmbe) |
| { |
| int ret; |
| |
| jump_to_uncached(); |
| ret = __set_pmb_entry(pmbe->vpn, pmbe->ppn, pmbe->flags, &pmbe->entry); |
| back_to_cached(); |
| |
| return ret; |
| } |
| |
| void __uses_jump_to_uncached clear_pmb_entry(struct pmb_entry *pmbe) |
| { |
| unsigned int entry = pmbe->entry; |
| unsigned long addr; |
| |
| /* |
| * Don't allow clearing of wired init entries, P1 or P2 access |
| * without a corresponding mapping in the PMB will lead to reset |
| * by the TLB. |
| */ |
| if (unlikely(entry < ARRAY_SIZE(pmb_init_map) || |
| entry >= NR_PMB_ENTRIES)) |
| return; |
| |
| jump_to_uncached(); |
| |
| /* Clear V-bit */ |
| addr = mk_pmb_addr(entry); |
| ctrl_outl(ctrl_inl(addr) & ~PMB_V, addr); |
| |
| addr = mk_pmb_data(entry); |
| ctrl_outl(ctrl_inl(addr) & ~PMB_V, addr); |
| |
| back_to_cached(); |
| |
| clear_bit(entry, &pmb_map); |
| } |
| |
| |
| static struct { |
| unsigned long size; |
| int flag; |
| } pmb_sizes[] = { |
| { .size = 0x20000000, .flag = PMB_SZ_512M, }, |
| { .size = 0x08000000, .flag = PMB_SZ_128M, }, |
| { .size = 0x04000000, .flag = PMB_SZ_64M, }, |
| { .size = 0x01000000, .flag = PMB_SZ_16M, }, |
| }; |
| |
| long pmb_remap(unsigned long vaddr, unsigned long phys, |
| unsigned long size, unsigned long flags) |
| { |
| struct pmb_entry *pmbp; |
| unsigned long wanted; |
| int pmb_flags, i; |
| |
| /* Convert typical pgprot value to the PMB equivalent */ |
| if (flags & _PAGE_CACHABLE) { |
| if (flags & _PAGE_WT) |
| pmb_flags = PMB_WT; |
| else |
| pmb_flags = PMB_C; |
| } else |
| pmb_flags = PMB_WT | PMB_UB; |
| |
| pmbp = NULL; |
| wanted = size; |
| |
| again: |
| for (i = 0; i < ARRAY_SIZE(pmb_sizes); i++) { |
| struct pmb_entry *pmbe; |
| int ret; |
| |
| if (size < pmb_sizes[i].size) |
| continue; |
| |
| pmbe = pmb_alloc(vaddr, phys, pmb_flags | pmb_sizes[i].flag); |
| if (IS_ERR(pmbe)) |
| return PTR_ERR(pmbe); |
| |
| ret = set_pmb_entry(pmbe); |
| if (ret != 0) { |
| pmb_free(pmbe); |
| return -EBUSY; |
| } |
| |
| phys += pmb_sizes[i].size; |
| vaddr += pmb_sizes[i].size; |
| size -= pmb_sizes[i].size; |
| |
| /* |
| * Link adjacent entries that span multiple PMB entries |
| * for easier tear-down. |
| */ |
| if (likely(pmbp)) |
| pmbp->link = pmbe; |
| |
| pmbp = pmbe; |
| } |
| |
| if (size >= 0x1000000) |
| goto again; |
| |
| return wanted - size; |
| } |
| |
| void pmb_unmap(unsigned long addr) |
| { |
| struct pmb_entry **p, *pmbe; |
| |
| for (p = &pmb_list; (pmbe = *p); p = &pmbe->next) |
| if (pmbe->vpn == addr) |
| break; |
| |
| if (unlikely(!pmbe)) |
| return; |
| |
| WARN_ON(!test_bit(pmbe->entry, &pmb_map)); |
| |
| do { |
| struct pmb_entry *pmblink = pmbe; |
| |
| clear_pmb_entry(pmbe); |
| pmbe = pmblink->link; |
| |
| pmb_free(pmblink); |
| } while (pmbe); |
| } |
| |
| static void pmb_cache_ctor(void *pmb) |
| { |
| struct pmb_entry *pmbe = pmb; |
| |
| memset(pmb, 0, sizeof(struct pmb_entry)); |
| |
| pmbe->entry = PMB_NO_ENTRY; |
| } |
| |
| static int __uses_jump_to_uncached pmb_init(void) |
| { |
| unsigned int nr_entries = ARRAY_SIZE(pmb_init_map); |
| unsigned int entry, i; |
| |
| BUG_ON(unlikely(nr_entries >= NR_PMB_ENTRIES)); |
| |
| pmb_cache = kmem_cache_create("pmb", sizeof(struct pmb_entry), 0, |
| SLAB_PANIC, pmb_cache_ctor); |
| |
| jump_to_uncached(); |
| |
| /* |
| * Ordering is important, P2 must be mapped in the PMB before we |
| * can set PMB.SE, and P1 must be mapped before we jump back to |
| * P1 space. |
| */ |
| for (entry = 0; entry < nr_entries; entry++) { |
| struct pmb_entry *pmbe = pmb_init_map + entry; |
| |
| __set_pmb_entry(pmbe->vpn, pmbe->ppn, pmbe->flags, &entry); |
| } |
| |
| ctrl_outl(0, PMB_IRMCR); |
| |
| /* PMB.SE and UB[7] */ |
| ctrl_outl((1 << 31) | (1 << 7), PMB_PASCR); |
| |
| /* Flush out the TLB */ |
| i = ctrl_inl(MMUCR); |
| i |= MMUCR_TI; |
| ctrl_outl(i, MMUCR); |
| |
| back_to_cached(); |
| |
| return 0; |
| } |
| arch_initcall(pmb_init); |
| |
| static int pmb_seq_show(struct seq_file *file, void *iter) |
| { |
| int i; |
| |
| seq_printf(file, "V: Valid, C: Cacheable, WT: Write-Through\n" |
| "CB: Copy-Back, B: Buffered, UB: Unbuffered\n"); |
| seq_printf(file, "ety vpn ppn size flags\n"); |
| |
| for (i = 0; i < NR_PMB_ENTRIES; i++) { |
| unsigned long addr, data; |
| unsigned int size; |
| char *sz_str = NULL; |
| |
| addr = ctrl_inl(mk_pmb_addr(i)); |
| data = ctrl_inl(mk_pmb_data(i)); |
| |
| size = data & PMB_SZ_MASK; |
| sz_str = (size == PMB_SZ_16M) ? " 16MB": |
| (size == PMB_SZ_64M) ? " 64MB": |
| (size == PMB_SZ_128M) ? "128MB": |
| "512MB"; |
| |
| /* 02: V 0x88 0x08 128MB C CB B */ |
| seq_printf(file, "%02d: %c 0x%02lx 0x%02lx %s %c %s %s\n", |
| i, ((addr & PMB_V) && (data & PMB_V)) ? 'V' : ' ', |
| (addr >> 24) & 0xff, (data >> 24) & 0xff, |
| sz_str, (data & PMB_C) ? 'C' : ' ', |
| (data & PMB_WT) ? "WT" : "CB", |
| (data & PMB_UB) ? "UB" : " B"); |
| } |
| |
| return 0; |
| } |
| |
| static int pmb_debugfs_open(struct inode *inode, struct file *file) |
| { |
| return single_open(file, pmb_seq_show, NULL); |
| } |
| |
| static const struct file_operations pmb_debugfs_fops = { |
| .owner = THIS_MODULE, |
| .open = pmb_debugfs_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = single_release, |
| }; |
| |
| static int __init pmb_debugfs_init(void) |
| { |
| struct dentry *dentry; |
| |
| dentry = debugfs_create_file("pmb", S_IFREG | S_IRUGO, |
| sh_debugfs_root, NULL, &pmb_debugfs_fops); |
| if (!dentry) |
| return -ENOMEM; |
| if (IS_ERR(dentry)) |
| return PTR_ERR(dentry); |
| |
| return 0; |
| } |
| postcore_initcall(pmb_debugfs_init); |