3 files changed, 67 insertions, 65 deletions

diff --git a/arch/sh/mm/Kconfig b/arch/sh/mm/Kconfig
index 358c860aeb9b..860cd24b4205 100644
--- a/arch/sh/mm/Kconfig
+++ b/arch/sh/mm/Kconfig
@@ -80,30 +80,18 @@ config 32BIT
         bool
         default y if CPU_SH5
 
-config PMB_ENABLE
-        bool "Support 32-bit physical addressing through PMB"
-        depends on MMU && EXPERIMENTAL && CPU_SH4A && !CPU_SH4AL_DSP
-        help
-          If you say Y here, physical addressing will be extended to
-          32-bits through the SH-4A PMB. If this is not set, legacy
-          29-bit physical addressing will be used.
-
-choice
-        prompt "PMB handling type"
-        depends on PMB_ENABLE
-        default PMB_FIXED
-
 config PMB
-        bool "PMB"
+        bool "Support 32-bit physical addressing through PMB"
         depends on MMU && EXPERIMENTAL && CPU_SH4A && !CPU_SH4AL_DSP
+        select 32BIT
         help
           If you say Y here, physical addressing will be extended to
           32-bits through the SH-4A PMB. If this is not set, legacy
           29-bit physical addressing will be used.
 
-config PMB_FIXED
-        bool "fixed PMB"
-        depends on MMU && EXPERIMENTAL && CPU_SH4A && !CPU_SH4AL_DSP
+config PMB_LEGACY
+        bool "Support legacy boot mappings for PMB"
+        depends on PMB
         select 32BIT
         help
           If this option is enabled, fixed PMB mappings are inherited
@@ -111,8 +99,6 @@ config PMB_FIXED
           management. This is the closest to legacy 29-bit physical mode,
           and allows systems to support up to 512MiB of system memory.
 
-endchoice
-
 config X2TLB
         bool "Enable extended TLB mode"
         depends on (CPU_SHX2 || CPU_SHX3) && MMU && EXPERIMENTAL
diff --git a/arch/sh/mm/Makefile b/arch/sh/mm/Makefile
index 9fa11d655044..edde8bdd681d 100644
--- a/arch/sh/mm/Makefile
+++ b/arch/sh/mm/Makefile
@@ -33,7 +33,7 @@ obj-y				+= $(tlb-y)
 endif
 
 obj-$(CONFIG_HUGETLB_PAGE)      += hugetlbpage.o
-obj-$(CONFIG_PMB_ENABLE)        += pmb.o
+obj-$(CONFIG_PMB)               += pmb.o
 obj-$(CONFIG_NUMA)              += numa.o
 
 # Special flags for fault_64.o.  This puts restrictions on the number of
diff --git a/arch/sh/mm/pmb.c b/arch/sh/mm/pmb.c
index 280f6a166035..8f7dbf183fb0 100644
--- a/arch/sh/mm/pmb.c
+++ b/arch/sh/mm/pmb.c
@@ -3,7 +3,7 @@
  *
  * Privileged Space Mapping Buffer (PMB) Support.
  *
- * Copyright (C) 2005, 2006, 2007 Paul Mundt
+ * Copyright (C) 2005 - 2010 Paul Mundt
  *
  * P1/P2 Section mapping definitions from map32.h, which was:
  *
@@ -279,51 +279,12 @@ static void __pmb_unmap(struct pmb_entry *pmbe)
         } while (pmbe);
 }
 
-#ifdef CONFIG_PMB
-int __uses_jump_to_uncached pmb_init(void)
-{
-        unsigned int i;
-        long size, ret;
-
-        jump_to_uncached();
-
-        /*
-         * Insert PMB entries for the P1 and P2 areas so that, after
-         * we've switched the MMU to 32-bit mode, the semantics of P1
-         * and P2 are the same as in 29-bit mode, e.g.
-         *
-         *      P1 - provides a cached window onto physical memory
-         *      P2 - provides an uncached window onto physical memory
-         */
-        size = __MEMORY_START + __MEMORY_SIZE;
-
-        ret = pmb_remap(P1SEG, 0x00000000, size, PMB_C);
-        BUG_ON(ret != size);
-
-        ret = pmb_remap(P2SEG, 0x00000000, size, PMB_WT | PMB_UB);
-        BUG_ON(ret != size);
-
-        ctrl_outl(0, PMB_IRMCR);
-
-        /* PMB.SE and UB[7] */
-        ctrl_outl(PASCR_SE | (1 << 7), PMB_PASCR);
-
-        /* Flush out the TLB */
-        i =  ctrl_inl(MMUCR);
-        i |= MMUCR_TI;
-        ctrl_outl(i, MMUCR);
-
-        back_to_cached();
-
-        return 0;
-}
-#else
-int __uses_jump_to_uncached pmb_init(void)
+#ifdef CONFIG_PMB_LEGACY
+static int pmb_apply_legacy_mappings(void)
 {
         int i;
         unsigned long addr, data;
-
-        jump_to_uncached();
+        unsigned int applied = 0;
 
         for (i = 0; i < PMB_ENTRY_MAX; i++) {
                 struct pmb_entry *pmbe;
@@ -357,13 +318,69 @@ int __uses_jump_to_uncached pmb_init(void)
 
                 pmbe = pmb_alloc(vpn, ppn, flags, i);
                 WARN_ON(IS_ERR(pmbe));
+
+                applied++;
+        }
+
+        return (applied == 0);
+}
+#else
+static inline int pmb_apply_legacy_mappings(void)
+{
+        return 1;
+}
+#endif
+
+int __uses_jump_to_uncached pmb_init(void)
+{
+        unsigned int i;
+        unsigned long size, 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;
         }
 
+        /*
+         * Insert PMB entries for the P1 and P2 areas so that, after
+         * we've switched the MMU to 32-bit mode, the semantics of P1
+         * and P2 are the same as in 29-bit mode, e.g.
+         *
+         *      P1 - provides a cached window onto physical memory
+         *      P2 - provides an uncached window onto physical memory
+         */
+        size = (unsigned long)__MEMORY_START + __MEMORY_SIZE;
+
+        ret = pmb_remap(P1SEG, 0x00000000, size, PMB_C);
+        BUG_ON(ret != size);
+
+        ret = pmb_remap(P2SEG, 0x00000000, size, PMB_WT | PMB_UB);
+        BUG_ON(ret != size);
+
+        ctrl_outl(0, PMB_IRMCR);
+
+        /* PMB.SE and UB[7] */
+        ctrl_outl(PASCR_SE | (1 << 7), PMB_PASCR);
+
+        /* Flush out the TLB */
+        i =  ctrl_inl(MMUCR);
+        i |= MMUCR_TI;
+        ctrl_outl(i, MMUCR);
+
         back_to_cached();
 
         return 0;
 }
-#endif /* CONFIG_PMB */
 
 static int pmb_seq_show(struct seq_file *file, void *iter)
 {
@@ -462,6 +479,5 @@ static int __init pmb_sysdev_init(void)
 {
         return sysdev_driver_register(&cpu_sysdev_class, &pmb_sysdev_driver);
 }
-
 subsys_initcall(pmb_sysdev_init);
 #endif