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);