diff options
Diffstat (limited to 'arch/sh/mm/pmb.c')
| -rw-r--r-- | arch/sh/mm/pmb.c | 400 |
1 files changed, 400 insertions, 0 deletions
diff --git a/arch/sh/mm/pmb.c b/arch/sh/mm/pmb.c new file mode 100644 index 00000000000..92e745341e4 --- /dev/null +++ b/arch/sh/mm/pmb.c @@ -0,0 +1,400 @@ +/* + * arch/sh/mm/pmb.c + * + * Privileged Space Mapping Buffer (PMB) Support. + * + * Copyright (C) 2005, 2006 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> + +#define NR_PMB_ENTRIES 16 + +static kmem_cache_t *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; +} + +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; + + return pmbe; +} + +void pmb_free(struct pmb_entry *pmbe) +{ + 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_SH_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 set_pmb_entry(struct pmb_entry *pmbe) +{ + int ret; + + jump_to_P2(); + ret = __set_pmb_entry(pmbe->vpn, pmbe->ppn, pmbe->flags, &pmbe->entry); + back_to_P1(); + + return ret; +} + +void 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_P2(); + + /* 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_P1(); + + clear_bit(entry, &pmb_map); +} + +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; + } +} + +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, kmem_cache_t *cachep, unsigned long flags) +{ + struct pmb_entry *pmbe = pmb; + + memset(pmb, 0, sizeof(struct pmb_entry)); + + spin_lock_irq(&pmb_list_lock); + + pmbe->entry = PMB_NO_ENTRY; + pmb_list_add(pmbe); + + spin_unlock_irq(&pmb_list_lock); +} + +static void pmb_cache_dtor(void *pmb, kmem_cache_t *cachep, unsigned long flags) +{ + spin_lock_irq(&pmb_list_lock); + pmb_list_del(pmb); + spin_unlock_irq(&pmb_list_lock); +} + +static int __init pmb_init(void) +{ + unsigned int nr_entries = ARRAY_SIZE(pmb_init_map); + unsigned int entry; + + BUG_ON(unlikely(nr_entries >= NR_PMB_ENTRIES)); + + pmb_cache = kmem_cache_create("pmb", sizeof(struct pmb_entry), + 0, 0, pmb_cache_ctor, pmb_cache_dtor); + BUG_ON(!pmb_cache); + + jump_to_P2(); + + /* + * 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); + + back_to_P1(); + + 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 struct file_operations pmb_debugfs_fops = { + .owner = THIS_MODULE, + .open = pmb_debugfs_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; + +static int __init pmb_debugfs_init(void) +{ + struct dentry *dentry; + + dentry = debugfs_create_file("pmb", S_IFREG | S_IRUGO, + NULL, NULL, &pmb_debugfs_fops); + if (IS_ERR(dentry)) + return PTR_ERR(dentry); + + return 0; +} +postcore_initcall(pmb_debugfs_init); |