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Diffstat (limited to 'arch/sh/mm/pmb.c')
-rw-r--r--arch/sh/mm/pmb.c243
1 files changed, 207 insertions, 36 deletions
diff --git a/arch/sh/mm/pmb.c b/arch/sh/mm/pmb.c
index b9d5476e1284..198bcff5e96f 100644
--- a/arch/sh/mm/pmb.c
+++ b/arch/sh/mm/pmb.c
@@ -52,7 +52,7 @@ struct pmb_entry {
struct pmb_entry *link;
};
-static void pmb_unmap_entry(struct pmb_entry *);
+static void pmb_unmap_entry(struct pmb_entry *, int depth);
static DEFINE_RWLOCK(pmb_rwlock);
static struct pmb_entry pmb_entry_list[NR_PMB_ENTRIES];
@@ -115,13 +115,14 @@ static struct pmb_entry *pmb_alloc(unsigned long vpn, unsigned long ppn,
pmbe = &pmb_entry_list[pos];
+ memset(pmbe, 0, sizeof(struct pmb_entry));
+
spin_lock_init(&pmbe->lock);
pmbe->vpn = vpn;
pmbe->ppn = ppn;
pmbe->flags = flags;
pmbe->entry = pos;
- pmbe->size = 0;
return pmbe;
@@ -133,7 +134,9 @@ out:
static void pmb_free(struct pmb_entry *pmbe)
{
__clear_bit(pmbe->entry, pmb_map);
- pmbe->entry = PMB_NO_ENTRY;
+
+ pmbe->entry = PMB_NO_ENTRY;
+ pmbe->link = NULL;
}
/*
@@ -161,9 +164,6 @@ static __always_inline unsigned long pmb_cache_flags(void)
*/
static void __set_pmb_entry(struct pmb_entry *pmbe)
{
- pmbe->flags &= ~PMB_CACHE_MASK;
- pmbe->flags |= pmb_cache_flags();
-
writel_uncached(pmbe->vpn | PMB_V, mk_pmb_addr(pmbe->entry));
writel_uncached(pmbe->ppn | pmbe->flags | PMB_V,
mk_pmb_data(pmbe->entry));
@@ -280,7 +280,7 @@ again:
return wanted - size;
out:
- pmb_unmap_entry(pmbp);
+ pmb_unmap_entry(pmbp, NR_PMB_ENTRIES);
return err;
}
@@ -302,18 +302,40 @@ void pmb_unmap(unsigned long addr)
read_unlock(&pmb_rwlock);
- pmb_unmap_entry(pmbe);
+ pmb_unmap_entry(pmbe, NR_PMB_ENTRIES);
}
-static void pmb_unmap_entry(struct pmb_entry *pmbe)
+static bool pmb_can_merge(struct pmb_entry *a, struct pmb_entry *b)
{
- unsigned long flags;
+ return (b->vpn == (a->vpn + a->size)) &&
+ (b->ppn == (a->ppn + a->size)) &&
+ (b->flags == a->flags);
+}
- if (unlikely(!pmbe))
- return;
+static bool pmb_size_valid(unsigned long size)
+{
+ int i;
- write_lock_irqsave(&pmb_rwlock, flags);
+ for (i = 0; i < ARRAY_SIZE(pmb_sizes); i++)
+ if (pmb_sizes[i].size == size)
+ return true;
+
+ return false;
+}
+
+static int pmb_size_to_flags(unsigned long size)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(pmb_sizes); i++)
+ if (pmb_sizes[i].size == size)
+ return pmb_sizes[i].flag;
+ return 0;
+}
+
+static void __pmb_unmap_entry(struct pmb_entry *pmbe, int depth)
+{
do {
struct pmb_entry *pmblink = pmbe;
@@ -332,8 +354,18 @@ static void pmb_unmap_entry(struct pmb_entry *pmbe)
pmbe = pmblink->link;
pmb_free(pmblink);
- } while (pmbe);
+ } while (pmbe && --depth);
+}
+
+static void pmb_unmap_entry(struct pmb_entry *pmbe, int depth)
+{
+ unsigned long flags;
+ if (unlikely(!pmbe))
+ return;
+
+ write_lock_irqsave(&pmb_rwlock, flags);
+ __pmb_unmap_entry(pmbe, depth);
write_unlock_irqrestore(&pmb_rwlock, flags);
}
@@ -342,14 +374,40 @@ static __always_inline unsigned int pmb_ppn_in_range(unsigned long ppn)
return ppn >= __pa(memory_start) && ppn < __pa(memory_end);
}
-static int pmb_synchronize_mappings(void)
+static void __init pmb_notify(void)
{
- unsigned int applied = 0;
- struct pmb_entry *pmbp = NULL;
- int i, j;
+ int i;
pr_info("PMB: boot mappings:\n");
+ read_lock(&pmb_rwlock);
+
+ for (i = 0; i < ARRAY_SIZE(pmb_entry_list); i++) {
+ struct pmb_entry *pmbe;
+
+ if (!test_bit(i, pmb_map))
+ continue;
+
+ pmbe = &pmb_entry_list[i];
+
+ pr_info(" 0x%08lx -> 0x%08lx [ %4ldMB %2scached ]\n",
+ pmbe->vpn >> PAGE_SHIFT, pmbe->ppn >> PAGE_SHIFT,
+ pmbe->size >> 20, (pmbe->flags & PMB_C) ? "" : "un");
+ }
+
+ read_unlock(&pmb_rwlock);
+}
+
+/*
+ * 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.
+ */
+static void __init pmb_synchronize(void)
+{
+ struct pmb_entry *pmbp = NULL;
+ int i, j;
+
/*
* Run through the initial boot mappings, log the established
* ones, and blow away anything that falls outside of the valid
@@ -432,10 +490,10 @@ static int pmb_synchronize_mappings(void)
/*
* Compare the previous entry against the current one to
* see if the entries span a contiguous mapping. If so,
- * setup the entry links accordingly.
+ * setup the entry links accordingly. Compound mappings
+ * are later coalesced.
*/
- if ((pmbe->vpn == (pmbp->vpn + pmbp->size)) &&
- (pmbe->ppn == (pmbp->ppn + pmbp->size)))
+ if (pmb_can_merge(pmbp, pmbe))
pmbp->link = pmbe;
spin_unlock(&pmbp->lock);
@@ -444,37 +502,150 @@ static int pmb_synchronize_mappings(void)
pmbp = pmbe;
spin_unlock_irqrestore(&pmbe->lock, irqflags);
+ }
+}
- pr_info("\t0x%08lx -> 0x%08lx [ %ldMB %scached ]\n",
- vpn >> PAGE_SHIFT, ppn >> PAGE_SHIFT, pmbe->size >> 20,
- (data_val & PMB_C) ? "" : "un");
+static void __init pmb_merge(struct pmb_entry *head)
+{
+ unsigned long span, newsize;
+ struct pmb_entry *tail;
+ int i = 1, depth = 0;
+
+ span = newsize = head->size;
- applied++;
+ tail = head->link;
+ while (tail) {
+ span += tail->size;
+
+ if (pmb_size_valid(span)) {
+ newsize = span;
+ depth = i;
+ }
+
+ /* This is the end of the line.. */
+ if (!tail->link)
+ break;
+
+ tail = tail->link;
+ i++;
}
- return (applied == 0);
+ /*
+ * The merged page size must be valid.
+ */
+ if (!pmb_size_valid(newsize))
+ return;
+
+ head->flags &= ~PMB_SZ_MASK;
+ head->flags |= pmb_size_to_flags(newsize);
+
+ head->size = newsize;
+
+ __pmb_unmap_entry(head->link, depth);
+ __set_pmb_entry(head);
}
-int pmb_init(void)
+static void __init pmb_coalesce(void)
{
- int ret;
+ unsigned long flags;
+ int i;
+
+ write_lock_irqsave(&pmb_rwlock, flags);
+
+ for (i = 0; i < ARRAY_SIZE(pmb_entry_list); i++) {
+ struct pmb_entry *pmbe;
+
+ if (!test_bit(i, pmb_map))
+ continue;
+
+ pmbe = &pmb_entry_list[i];
+
+ /*
+ * We're only interested in compound mappings
+ */
+ if (!pmbe->link)
+ continue;
+
+ /*
+ * Nothing to do if it already uses the largest possible
+ * page size.
+ */
+ if (pmbe->size == SZ_512M)
+ continue;
+
+ pmb_merge(pmbe);
+ }
+
+ write_unlock_irqrestore(&pmb_rwlock, flags);
+}
+
+#ifdef CONFIG_UNCACHED_MAPPING
+static void __init pmb_resize(void)
+{
+ int i;
/*
- * 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.
+ * If the uncached mapping was constructed by the kernel, it will
+ * already be a reasonable size.
*/
- ret = pmb_synchronize_mappings();
- if (unlikely(ret == 0))
- return 0;
+ if (uncached_size == SZ_16M)
+ return;
+
+ read_lock(&pmb_rwlock);
+
+ for (i = 0; i < ARRAY_SIZE(pmb_entry_list); i++) {
+ struct pmb_entry *pmbe;
+ unsigned long flags;
+
+ if (!test_bit(i, pmb_map))
+ continue;
+
+ pmbe = &pmb_entry_list[i];
+
+ if (pmbe->vpn != uncached_start)
+ continue;
+
+ /*
+ * Found it, now resize it.
+ */
+ spin_lock_irqsave(&pmbe->lock, flags);
+
+ pmbe->size = SZ_16M;
+ pmbe->flags &= ~PMB_SZ_MASK;
+ pmbe->flags |= pmb_size_to_flags(pmbe->size);
+
+ uncached_resize(pmbe->size);
+
+ __set_pmb_entry(pmbe);
+
+ spin_unlock_irqrestore(&pmbe->lock, flags);
+ }
+
+ read_lock(&pmb_rwlock);
+}
+#endif
+
+void __init pmb_init(void)
+{
+ /* Synchronize software state */
+ pmb_synchronize();
+
+ /* Attempt to combine compound mappings */
+ pmb_coalesce();
+
+#ifdef CONFIG_UNCACHED_MAPPING
+ /* Resize initial mappings, if necessary */
+ pmb_resize();
+#endif
+
+ /* Log them */
+ pmb_notify();
writel_uncached(0, PMB_IRMCR);
/* Flush out the TLB */
__raw_writel(__raw_readl(MMUCR) | MMUCR_TI, MMUCR);
ctrl_barrier();
-
- return 0;
}
bool __in_29bit_mode(void)