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 000000000000..92e745341e4d
--- /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);