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-rw-r--r--arch/sh/mm/pmb.c400
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);