| /* |
| * arch/sh/mm/pmb.c |
| * |
| * Privileged Space Mapping Buffer (PMB) Support. |
| * |
| * Copyright (C) 2005 - 2010 Paul Mundt |
| * Copyright (C) 2010 Matt Fleming |
| * |
| * 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/sysdev.h> |
| #include <linux/cpu.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 void __pmb_unmap(struct pmb_entry *); |
| |
| static struct pmb_entry pmb_entry_list[NR_PMB_ENTRIES]; |
| static unsigned long pmb_map; |
| |
| 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 int pmb_alloc_entry(void) |
| { |
| unsigned int pos; |
| |
| repeat: |
| pos = find_first_zero_bit(&pmb_map, NR_PMB_ENTRIES); |
| |
| if (unlikely(pos > NR_PMB_ENTRIES)) |
| return -ENOSPC; |
| |
| if (test_and_set_bit(pos, &pmb_map)) |
| goto repeat; |
| |
| return pos; |
| } |
| |
| static struct pmb_entry *pmb_alloc(unsigned long vpn, unsigned long ppn, |
| unsigned long flags, int entry) |
| { |
| struct pmb_entry *pmbe; |
| int pos; |
| |
| if (entry == PMB_NO_ENTRY) { |
| pos = pmb_alloc_entry(); |
| if (pos < 0) |
| return ERR_PTR(pos); |
| } else { |
| if (test_bit(entry, &pmb_map)) |
| return ERR_PTR(-ENOSPC); |
| pos = entry; |
| } |
| |
| pmbe = &pmb_entry_list[pos]; |
| if (!pmbe) |
| return ERR_PTR(-ENOMEM); |
| |
| pmbe->vpn = vpn; |
| pmbe->ppn = ppn; |
| pmbe->flags = flags; |
| pmbe->entry = pos; |
| |
| return pmbe; |
| } |
| |
| static void pmb_free(struct pmb_entry *pmbe) |
| { |
| int pos = pmbe->entry; |
| |
| pmbe->vpn = 0; |
| pmbe->ppn = 0; |
| pmbe->flags = 0; |
| pmbe->entry = 0; |
| |
| clear_bit(pos, &pmb_map); |
| } |
| |
| /* |
| * Must be in P2 for __set_pmb_entry() |
| */ |
| static void __set_pmb_entry(unsigned long vpn, unsigned long ppn, |
| unsigned long flags, int pos) |
| { |
| 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)); |
| } |
| |
| static void __uses_jump_to_uncached set_pmb_entry(struct pmb_entry *pmbe) |
| { |
| jump_to_uncached(); |
| __set_pmb_entry(pmbe->vpn, pmbe->ppn, pmbe->flags, pmbe->entry); |
| back_to_cached(); |
| } |
| |
| static void __uses_jump_to_uncached clear_pmb_entry(struct pmb_entry *pmbe) |
| { |
| unsigned int entry = pmbe->entry; |
| unsigned long addr; |
| |
| if (unlikely(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(); |
| } |
| |
| |
| 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, *pmbe; |
| unsigned long wanted; |
| int pmb_flags, i; |
| long err; |
| |
| /* 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++) { |
| if (size < pmb_sizes[i].size) |
| continue; |
| |
| pmbe = pmb_alloc(vaddr, phys, pmb_flags | pmb_sizes[i].flag, |
| PMB_NO_ENTRY); |
| if (IS_ERR(pmbe)) { |
| err = PTR_ERR(pmbe); |
| goto out; |
| } |
| |
| set_pmb_entry(pmbe); |
| |
| 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; |
| |
| /* |
| * Instead of trying smaller sizes on every iteration |
| * (even if we succeed in allocating space), try using |
| * pmb_sizes[i].size again. |
| */ |
| i--; |
| } |
| |
| if (size >= 0x1000000) |
| goto again; |
| |
| return wanted - size; |
| |
| out: |
| if (pmbp) |
| __pmb_unmap(pmbp); |
| |
| return err; |
| } |
| |
| void pmb_unmap(unsigned long addr) |
| { |
| struct pmb_entry *pmbe = NULL; |
| int i; |
| |
| for (i = 0; i < ARRAY_SIZE(pmb_entry_list); i++) { |
| if (test_bit(i, &pmb_map)) { |
| pmbe = &pmb_entry_list[i]; |
| if (pmbe->vpn == addr) |
| break; |
| } |
| } |
| |
| if (unlikely(!pmbe)) |
| return; |
| |
| __pmb_unmap(pmbe); |
| } |
| |
| static void __pmb_unmap(struct pmb_entry *pmbe) |
| { |
| BUG_ON(!test_bit(pmbe->entry, &pmb_map)); |
| |
| do { |
| struct pmb_entry *pmblink = pmbe; |
| |
| /* |
| * We may be called before this pmb_entry has been |
| * entered into the PMB table via set_pmb_entry(), but |
| * that's OK because we've allocated a unique slot for |
| * this entry in pmb_alloc() (even if we haven't filled |
| * it yet). |
| * |
| * Therefore, calling clear_pmb_entry() is safe as no |
| * other mapping can be using that slot. |
| */ |
| clear_pmb_entry(pmbe); |
| |
| pmbe = pmblink->link; |
| |
| pmb_free(pmblink); |
| } while (pmbe); |
| } |
| |
| #ifdef CONFIG_PMB_LEGACY |
| static inline unsigned int pmb_ppn_in_range(unsigned long ppn) |
| { |
| return ppn >= __MEMORY_START && ppn < __MEMORY_START + __MEMORY_SIZE; |
| } |
| |
| static int pmb_apply_legacy_mappings(void) |
| { |
| unsigned int applied = 0; |
| int i; |
| |
| pr_info("PMB: Preserving legacy mappings:\n"); |
| |
| /* |
| * The following entries are setup by the bootloader. |
| * |
| * Entry VPN PPN V SZ C UB |
| * -------------------------------------------------------- |
| * 0 0xA0000000 0x00000000 1 64MB 0 0 |
| * 1 0xA4000000 0x04000000 1 16MB 0 0 |
| * 2 0xA6000000 0x08000000 1 16MB 0 0 |
| * 9 0x88000000 0x48000000 1 128MB 1 1 |
| * 10 0x90000000 0x50000000 1 128MB 1 1 |
| * 11 0x98000000 0x58000000 1 128MB 1 1 |
| * 13 0xA8000000 0x48000000 1 128MB 0 0 |
| * 14 0xB0000000 0x50000000 1 128MB 0 0 |
| * 15 0xB8000000 0x58000000 1 128MB 0 0 |
| * |
| * The only entries the we need are the ones that map the kernel |
| * at the cached and uncached addresses. |
| */ |
| for (i = 0; i < PMB_ENTRY_MAX; i++) { |
| unsigned long addr, data; |
| unsigned long addr_val, data_val; |
| unsigned long ppn, vpn; |
| |
| addr = mk_pmb_addr(i); |
| data = mk_pmb_data(i); |
| |
| addr_val = __raw_readl(addr); |
| data_val = __raw_readl(data); |
| |
| /* |
| * Skip over any bogus entries |
| */ |
| if (!(data_val & PMB_V) || !(addr_val & PMB_V)) |
| continue; |
| |
| ppn = data_val & PMB_PFN_MASK; |
| vpn = addr_val & PMB_PFN_MASK; |
| |
| /* |
| * Only preserve in-range mappings. |
| */ |
| if (pmb_ppn_in_range(ppn)) { |
| unsigned int size; |
| char *sz_str = NULL; |
| |
| size = data_val & PMB_SZ_MASK; |
| |
| sz_str = (size == PMB_SZ_16M) ? " 16MB": |
| (size == PMB_SZ_64M) ? " 64MB": |
| (size == PMB_SZ_128M) ? "128MB": |
| "512MB"; |
| |
| pr_info("\t0x%08lx -> 0x%08lx [ %s %scached ]\n", |
| vpn >> PAGE_SHIFT, ppn >> PAGE_SHIFT, sz_str, |
| (data_val & PMB_C) ? "" : "un"); |
| |
| applied++; |
| } else { |
| /* |
| * Invalidate anything out of bounds. |
| */ |
| __raw_writel(addr_val & ~PMB_V, addr); |
| __raw_writel(data_val & ~PMB_V, data); |
| } |
| } |
| |
| return (applied == 0); |
| } |
| #else |
| static inline int pmb_apply_legacy_mappings(void) |
| { |
| return 1; |
| } |
| #endif |
| |
| int __uses_jump_to_uncached pmb_init(void) |
| { |
| int i; |
| unsigned long addr, data; |
| unsigned long ret; |
| |
| jump_to_uncached(); |
| |
| /* |
| * Attempt to apply the legacy boot mappings if configured. If |
| * this is successful then we simply carry on with those and |
| * don't bother establishing additional memory mappings. Dynamic |
| * device mappings through pmb_remap() can still be bolted on |
| * after this. |
| */ |
| ret = pmb_apply_legacy_mappings(); |
| if (ret == 0) { |
| back_to_cached(); |
| return 0; |
| } |
| |
| /* |
| * Sync our software copy of the PMB mappings with those in |
| * hardware. The mappings in the hardware PMB were either set up |
| * by the bootloader or very early on by the kernel. |
| */ |
| for (i = 0; i < PMB_ENTRY_MAX; i++) { |
| struct pmb_entry *pmbe; |
| unsigned long vpn, ppn, flags; |
| |
| addr = PMB_DATA + (i << PMB_E_SHIFT); |
| data = ctrl_inl(addr); |
| if (!(data & PMB_V)) |
| continue; |
| |
| if (data & PMB_C) { |
| #if defined(CONFIG_CACHE_WRITETHROUGH) |
| data |= PMB_WT; |
| #elif defined(CONFIG_CACHE_WRITEBACK) |
| data &= ~PMB_WT; |
| #else |
| data &= ~(PMB_C | PMB_WT); |
| #endif |
| } |
| ctrl_outl(data, addr); |
| |
| ppn = data & PMB_PFN_MASK; |
| |
| flags = data & (PMB_C | PMB_WT | PMB_UB); |
| flags |= data & PMB_SZ_MASK; |
| |
| addr = PMB_ADDR + (i << PMB_E_SHIFT); |
| data = ctrl_inl(addr); |
| |
| vpn = data & PMB_PFN_MASK; |
| |
| pmbe = pmb_alloc(vpn, ppn, flags, i); |
| WARN_ON(IS_ERR(pmbe)); |
| } |
| |
| ctrl_outl(0, PMB_IRMCR); |
| |
| /* Flush out the TLB */ |
| i = ctrl_inl(MMUCR); |
| i |= MMUCR_TI; |
| ctrl_outl(i, MMUCR); |
| |
| back_to_cached(); |
| |
| return 0; |
| } |
| |
| bool __in_29bit_mode(void) |
| { |
| return (__raw_readl(PMB_PASCR) & PASCR_SE) == 0; |
| } |
| |
| 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); |
| |
| #ifdef CONFIG_PM |
| static int pmb_sysdev_suspend(struct sys_device *dev, pm_message_t state) |
| { |
| static pm_message_t prev_state; |
| int i; |
| |
| /* Restore the PMB after a resume from hibernation */ |
| if (state.event == PM_EVENT_ON && |
| prev_state.event == PM_EVENT_FREEZE) { |
| struct pmb_entry *pmbe; |
| for (i = 0; i < ARRAY_SIZE(pmb_entry_list); i++) { |
| if (test_bit(i, &pmb_map)) { |
| pmbe = &pmb_entry_list[i]; |
| set_pmb_entry(pmbe); |
| } |
| } |
| } |
| prev_state = state; |
| return 0; |
| } |
| |
| static int pmb_sysdev_resume(struct sys_device *dev) |
| { |
| return pmb_sysdev_suspend(dev, PMSG_ON); |
| } |
| |
| static struct sysdev_driver pmb_sysdev_driver = { |
| .suspend = pmb_sysdev_suspend, |
| .resume = pmb_sysdev_resume, |
| }; |
| |
| static int __init pmb_sysdev_init(void) |
| { |
| return sysdev_driver_register(&cpu_sysdev_class, &pmb_sysdev_driver); |
| } |
| subsys_initcall(pmb_sysdev_init); |
| #endif |