sh: Migrate SH-4 cacheflush ops to function pointers.

This paves the way for allowing individual CPUs to overload the
individual flushing routines that they care about without having to
depend on weak aliases. SH-4 is converted over initially, as it wires
up pretty much everything. The majority of the other CPUs will simply use
the default no-op implementation with their own region flushers wired up.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

5 files changed, 133 insertions, 46 deletions

diff --git a/arch/sh/mm/cache-sh4.c b/arch/sh/mm/cache-sh4.c
index b5860535e61f..05cb04bc3940 100644
--- a/arch/sh/mm/cache-sh4.c
+++ b/arch/sh/mm/cache-sh4.c
@@ -26,13 +26,6 @@
 #define MAX_DCACHE_PAGES        64      /* XXX: Tune for ways */
 #define MAX_ICACHE_PAGES        32
 
-static void __flush_dcache_segment_1way(unsigned long start,
-                                        unsigned long extent);
-static void __flush_dcache_segment_2way(unsigned long start,
-                                        unsigned long extent);
-static void __flush_dcache_segment_4way(unsigned long start,
-                                        unsigned long extent);
-
 static void __flush_cache_4096(unsigned long addr, unsigned long phys,
                                unsigned long exec_offset);
 
@@ -45,38 +38,12 @@ static void (*__flush_dcache_segment_fn)(unsigned long, unsigned long) =
         (void (*)(unsigned long, unsigned long))0xdeadbeef;
 
 /*
- * SH-4 has virtually indexed and physically tagged cache.
- */
-void __init sh4_cache_init(void)
-{
-        printk("PVR=%08x CVR=%08x PRR=%08x\n",
-                ctrl_inl(CCN_PVR),
-                ctrl_inl(CCN_CVR),
-                ctrl_inl(CCN_PRR));
-
-        switch (boot_cpu_data.dcache.ways) {
-        case 1:
-                __flush_dcache_segment_fn = __flush_dcache_segment_1way;
-                break;
-        case 2:
-                __flush_dcache_segment_fn = __flush_dcache_segment_2way;
-                break;
-        case 4:
-                __flush_dcache_segment_fn = __flush_dcache_segment_4way;
-                break;
-        default:
-                panic("unknown number of cache ways\n");
-                break;
-        }
-}
-
-/*
  * Write back the range of D-cache, and purge the I-cache.
  *
  * Called from kernel/module.c:sys_init_module and routine for a.out format,
  * signal handler code and kprobes code
  */
-void flush_icache_range(unsigned long start, unsigned long end)
+static void sh4_flush_icache_range(unsigned long start, unsigned long end)
 {
         int icacheaddr;
         unsigned long flags, v;
@@ -137,7 +104,7 @@ static inline void flush_cache_4096(unsigned long start,
  * Write back & invalidate the D-cache of the page.
  * (To avoid "alias" issues)
  */
-void flush_dcache_page(struct page *page)
+static void sh4_flush_dcache_page(struct page *page)
 {
         struct address_space *mapping = page_mapping(page);
 
@@ -188,7 +155,7 @@ static inline void flush_dcache_all(void)
         wmb();
 }
 
-void flush_cache_all(void)
+static void sh4_flush_cache_all(void)
 {
         flush_dcache_all();
         flush_icache_all();
@@ -280,7 +247,7 @@ loop_exit:
  *
  * Caller takes mm->mmap_sem.
  */
-void flush_cache_mm(struct mm_struct *mm)
+static void sh4_flush_cache_mm(struct mm_struct *mm)
 {
         if (cpu_context(smp_processor_id(), mm) == NO_CONTEXT)
                 return;
@@ -320,8 +287,8 @@ void flush_cache_mm(struct mm_struct *mm)
  * ADDR: Virtual Address (U0 address)
  * PFN: Physical page number
  */
-void flush_cache_page(struct vm_area_struct *vma, unsigned long address,
-                      unsigned long pfn)
+static void sh4_flush_cache_page(struct vm_area_struct *vma,
+                unsigned long address, unsigned long pfn)
 {
         unsigned long phys = pfn << PAGE_SHIFT;
         unsigned int alias_mask;
@@ -368,8 +335,8 @@ void flush_cache_page(struct vm_area_struct *vma, unsigned long address,
  * Flushing the cache lines for U0 only isn't enough.
  * We need to flush for P1 too, which may contain aliases.
  */
-void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
-                       unsigned long end)
+static void sh4_flush_cache_range(struct vm_area_struct *vma,
+                unsigned long start, unsigned long end)
 {
         if (cpu_context(smp_processor_id(), vma->vm_mm) == NO_CONTEXT)
                 return;
@@ -668,3 +635,41 @@ static void __flush_dcache_segment_4way(unsigned long start,
                 a3 += linesz;
         } while (a0 < a0e);
 }
+
+extern void __weak sh4__flush_region_init(void);
+
+/*
+ * SH-4 has virtually indexed and physically tagged cache.
+ */
+void __init sh4_cache_init(void)
+{
+        printk("PVR=%08x CVR=%08x PRR=%08x\n",
+                ctrl_inl(CCN_PVR),
+                ctrl_inl(CCN_CVR),
+                ctrl_inl(CCN_PRR));
+
+        switch (boot_cpu_data.dcache.ways) {
+        case 1:
+                __flush_dcache_segment_fn = __flush_dcache_segment_1way;
+                break;
+        case 2:
+                __flush_dcache_segment_fn = __flush_dcache_segment_2way;
+                break;
+        case 4:
+                __flush_dcache_segment_fn = __flush_dcache_segment_4way;
+                break;
+        default:
+                panic("unknown number of cache ways\n");
+                break;
+        }
+
+        flush_icache_range      = sh4_flush_icache_range;
+        flush_dcache_page       = sh4_flush_dcache_page;
+        flush_cache_all         = sh4_flush_cache_all;
+        flush_cache_mm          = sh4_flush_cache_mm;
+        flush_cache_dup_mm      = sh4_flush_cache_mm;
+        flush_cache_page        = sh4_flush_cache_page;
+        flush_cache_range       = sh4_flush_cache_range;
+
+        sh4__flush_region_init();
+}
diff --git a/arch/sh/mm/cache-sh5.c b/arch/sh/mm/cache-sh5.c
index a50d23caf015..a8f5142dc2cf 100644
--- a/arch/sh/mm/cache-sh5.c
+++ b/arch/sh/mm/cache-sh5.c
@@ -20,6 +20,8 @@
 #include <asm/uaccess.h>
 #include <asm/mmu_context.h>
 
+extern void __weak sh4__flush_region_init(void);
+
 /* Wired TLB entry for the D-cache */
 static unsigned long long dtlb_cache_slot;
 
@@ -27,6 +29,8 @@ void __init cpu_cache_init(void)
 {
         /* Reserve a slot for dcache colouring in the DTLB */
         dtlb_cache_slot = sh64_get_wired_dtlb_entry();
+
+        sh4__flush_region_init();
 }
 
 void __init kmap_coherent_init(void)
diff --git a/arch/sh/mm/cache.c b/arch/sh/mm/cache.c
index a31e5c46e7a6..da5bc6ac1b28 100644
--- a/arch/sh/mm/cache.c
+++ b/arch/sh/mm/cache.c
@@ -15,6 +15,62 @@
 #include <asm/mmu_context.h>
 #include <asm/cacheflush.h>
 
+void (*flush_cache_all)(void);
+void (*flush_cache_mm)(struct mm_struct *mm);
+void (*flush_cache_dup_mm)(struct mm_struct *mm);
+void (*flush_cache_page)(struct vm_area_struct *vma,
+                                unsigned long addr, unsigned long pfn);
+void (*flush_cache_range)(struct vm_area_struct *vma,
+                                 unsigned long start, unsigned long end);
+void (*flush_dcache_page)(struct page *page);
+void (*flush_icache_range)(unsigned long start, unsigned long end);
+void (*flush_icache_page)(struct vm_area_struct *vma,
+                                 struct page *page);
+void (*flush_cache_sigtramp)(unsigned long address);
+void (*__flush_wback_region)(void *start, int size);
+void (*__flush_purge_region)(void *start, int size);
+void (*__flush_invalidate_region)(void *start, int size);
+
+static inline void noop_flush_cache_all(void)
+{
+}
+
+static inline void noop_flush_cache_mm(struct mm_struct *mm)
+{
+}
+
+static inline void noop_flush_cache_page(struct vm_area_struct *vma,
+                                unsigned long addr, unsigned long pfn)
+{
+}
+
+static inline void noop_flush_cache_range(struct vm_area_struct *vma,
+                                 unsigned long start, unsigned long end)
+{
+}
+
+static inline void noop_flush_dcache_page(struct page *page)
+{
+}
+
+static inline void noop_flush_icache_range(unsigned long start,
+                                           unsigned long end)
+{
+}
+
+static inline void noop_flush_icache_page(struct vm_area_struct *vma,
+                                          struct page *page)
+{
+}
+
+static inline void noop_flush_cache_sigtramp(unsigned long address)
+{
+}
+
+static inline void noop__flush_region(void *start, int size)
+{
+}
+
 void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
                        unsigned long vaddr, void *dst, const void *src,
                        unsigned long len)
@@ -174,6 +230,20 @@ void __init cpu_cache_init(void)
         compute_alias(&boot_cpu_data.dcache);
         compute_alias(&boot_cpu_data.scache);
 
+        flush_cache_all         = noop_flush_cache_all;
+        flush_cache_mm          = noop_flush_cache_mm;
+        flush_cache_dup_mm      = noop_flush_cache_mm;
+        flush_cache_page        = noop_flush_cache_page;
+        flush_cache_range       = noop_flush_cache_range;
+        flush_dcache_page       = noop_flush_dcache_page;
+        flush_icache_range      = noop_flush_icache_range;
+        flush_icache_page       = noop_flush_icache_page;
+        flush_cache_sigtramp    = noop_flush_cache_sigtramp;
+
+        __flush_wback_region            = noop__flush_region;
+        __flush_purge_region            = noop__flush_region;
+        __flush_invalidate_region       = noop__flush_region;
+
         if ((boot_cpu_data.family == CPU_FAMILY_SH4) ||
             (boot_cpu_data.family == CPU_FAMILY_SH4A) ||
             (boot_cpu_data.family == CPU_FAMILY_SH4AL_DSP)) {
diff --git a/arch/sh/mm/flush-sh4.c b/arch/sh/mm/flush-sh4.c
index 1b6b6a12a99b..99c50dc7551e 100644
--- a/arch/sh/mm/flush-sh4.c
+++ b/arch/sh/mm/flush-sh4.c
@@ -8,7 +8,7 @@
  * START: Virtual Address (U0, P1, or P3)
  * SIZE: Size of the region.
  */
-void __weak __flush_wback_region(void *start, int size)
+static void sh4__flush_wback_region(void *start, int size)
 {
         reg_size_t aligned_start, v, cnt, end;
 
@@ -51,7 +51,7 @@ void __weak __flush_wback_region(void *start, int size)
  * START: Virtual Address (U0, P1, or P3)
  * SIZE: Size of the region.
  */
-void __weak __flush_purge_region(void *start, int size)
+static void sh4__flush_purge_region(void *start, int size)
 {
         reg_size_t aligned_start, v, cnt, end;
 
@@ -90,7 +90,7 @@ void __weak __flush_purge_region(void *start, int size)
 /*
  * No write back please
  */
-void __weak __flush_invalidate_region(void *start, int size)
+static void sh4__flush_invalidate_region(void *start, int size)
 {
         reg_size_t aligned_start, v, cnt, end;
 
@@ -126,3 +126,10 @@ void __weak __flush_invalidate_region(void *start, int size)
                 cnt--;
         }
 }
+
+void __init sh4__flush_region_init(void)
+{
+        __flush_wback_region            = sh4__flush_wback_region;
+        __flush_invalidate_region       = sh4__flush_invalidate_region;
+        __flush_purge_region            = sh4__flush_purge_region;
+}
diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c
index cf0e9c5146b1..0a9b4d855bc9 100644
--- a/arch/sh/mm/init.c
+++ b/arch/sh/mm/init.c
@@ -210,6 +210,9 @@ void __init mem_init(void)
                         high_memory = node_high_memory;
         }
 
+        /* Set this up early, so we can take care of the zero page */
+        cpu_cache_init();
+
         /* clear the zero-page */
         memset(empty_zero_page, 0, PAGE_SIZE);
         __flush_wback_region(empty_zero_page, PAGE_SIZE);
@@ -230,8 +233,6 @@ void __init mem_init(void)
                 datasize >> 10,
                 initsize >> 10);
 
-        cpu_cache_init();
-
         /* Initialize the vDSO */
         vsyscall_init();
 }