sh: Provide the kmap_coherent() interface generically.

This plugs in kmap_coherent() for the non-SH4 cases to permit the
pg-mmu.c bits to be used generically across all CPUs. SH-5 is still in
the TODO state, but will move over to fixmap and the generic interface
gradually.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

arch/sh/include/asm/cacheflush.h

@@ -74,5 +74,9 @@ extern void copy_from_user_page(struct vm_area_struct *vma,
 #define flush_cache_vmap(start, end)		flush_cache_all()
 #define flush_cache_vunmap(start, end)		flush_cache_all()
 
+void kmap_coherent_init(void);
+void *kmap_coherent(struct page *page, unsigned long addr);
+void kunmap_coherent(void);
+
 #endif /* __KERNEL__ */
 #endif /* __ASM_SH_CACHEFLUSH_H */

arch/sh/include/asm/pgtable.h

@@ -158,12 +158,6 @@ extern void paging_init(void);
 extern void page_table_range_init(unsigned long start, unsigned long end,
 				  pgd_t *pgd);
 
-#if defined(CONFIG_MMU) && !defined(CONFIG_CPU_SH5)
-extern void kmap_coherent_init(void);
-#else
-#define kmap_coherent_init()	do { } while (0)
-#endif
-
 /* arch/sh/mm/mmap.c */
 #define HAVE_ARCH_UNMAPPED_AREA
 #define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN

arch/sh/mm/Makefile_32

@@ -15,7 +15,7 @@ endif
 obj-y			+= $(cache-y)
 
 mmu-y			:= tlb-nommu.o pg-nommu.o
-mmu-$(CONFIG_MMU)	:= fault_32.o tlbflush_32.o ioremap_32.o pg-mmu.o
+mmu-$(CONFIG_MMU)	:= fault_32.o kmap.o tlbflush_32.o ioremap_32.o pg-mmu.o
 
 obj-y			+= $(mmu-y)
 obj-$(CONFIG_DEBUG_FS)	+= asids-debugfs.o

arch/sh/mm/cache-sh5.c

@@ -29,6 +29,21 @@ void __init p3_cache_init(void)
 	dtlb_cache_slot	= sh64_get_wired_dtlb_entry();
 }
 
+void __init kmap_coherent_init(void)
+{
+	/* XXX ... */
+}
+
+void *kmap_coherent(struct page *page, unsigned long addr)
+{
+	/* XXX ... */
+	return NULL;
+}
+
+void kunmap_coherent(void)
+{
+}
+
 #ifdef CONFIG_DCACHE_DISABLED
 #define sh64_dcache_purge_all()					do { } while (0)
 #define sh64_dcache_purge_coloured_phy_page(paddr, eaddr)	do { } while (0)

arch/sh/mm/kmap.c

+/*
+ * arch/sh/mm/kmap.c
+ *
+ * Copyright (C) 1999, 2000, 2002  Niibe Yutaka
+ * Copyright (C) 2002 - 2009  Paul Mundt
+ *
+ * Released under the terms of the GNU GPL v2.0.
+ */
+#include <linux/mm.h>
+#include <linux/init.h>
+#include <linux/mutex.h>
+#include <linux/fs.h>
+#include <linux/highmem.h>
+#include <linux/module.h>
+#include <asm/mmu_context.h>
+#include <asm/cacheflush.h>
+
+#define kmap_get_fixmap_pte(vaddr)                                     \
+	pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr)), (vaddr))
+
+static pte_t *kmap_coherent_pte;
+
+void __init kmap_coherent_init(void)
+{
+	unsigned long vaddr;
+
+	if (!boot_cpu_data.dcache.n_aliases)
+		return;
+
+	/* cache the first coherent kmap pte */
+	vaddr = __fix_to_virt(FIX_CMAP_BEGIN);
+	kmap_coherent_pte = kmap_get_fixmap_pte(vaddr);
+}
+
+void *kmap_coherent(struct page *page, unsigned long addr)
+{
+	enum fixed_addresses idx;
+	unsigned long vaddr, flags;
+	pte_t pte;
+
+	BUG_ON(test_bit(PG_dcache_dirty, &page->flags));
+
+	inc_preempt_count();
+
+	idx = (addr & current_cpu_data.dcache.alias_mask) >> PAGE_SHIFT;
+	vaddr = __fix_to_virt(FIX_CMAP_END - idx);
+	pte = mk_pte(page, PAGE_KERNEL);
+
+	local_irq_save(flags);
+	flush_tlb_one(get_asid(), vaddr);
+	local_irq_restore(flags);
+
+	update_mmu_cache(NULL, vaddr, pte);
+
+	set_pte(kmap_coherent_pte - (FIX_CMAP_END - idx), pte);
+
+	return (void *)vaddr;
+}
+
+void kunmap_coherent(void)
+{
+	dec_preempt_count();
+	preempt_check_resched();
+}

arch/sh/mm/pg-mmu.c

@@ -15,54 +15,6 @@
 #include <asm/mmu_context.h>
 #include <asm/cacheflush.h>
 
-#define kmap_get_fixmap_pte(vaddr)                                     \
-	pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr)), (vaddr))
-
-static pte_t *kmap_coherent_pte;
-
-void __init kmap_coherent_init(void)
-{
-	unsigned long vaddr;
-
-	if (!boot_cpu_data.dcache.n_aliases)
-		return;
-
-	/* cache the first coherent kmap pte */
-	vaddr = __fix_to_virt(FIX_CMAP_BEGIN);
-	kmap_coherent_pte = kmap_get_fixmap_pte(vaddr);
-}
-
-static void *kmap_coherent(struct page *page, unsigned long addr)
-{
-	enum fixed_addresses idx;
-	unsigned long vaddr, flags;
-	pte_t pte;
-
-	BUG_ON(test_bit(PG_dcache_dirty, &page->flags));
-
-	inc_preempt_count();
-
-	idx = (addr & current_cpu_data.dcache.alias_mask) >> PAGE_SHIFT;
-	vaddr = __fix_to_virt(FIX_CMAP_END - idx);
-	pte = mk_pte(page, PAGE_KERNEL);
-
-	local_irq_save(flags);
-	flush_tlb_one(get_asid(), vaddr);
-	local_irq_restore(flags);
-
-	update_mmu_cache(NULL, vaddr, pte);
-
-	set_pte(kmap_coherent_pte - (FIX_CMAP_END - idx), pte);
-
-	return (void *)vaddr;
-}
-
-static inline void kunmap_coherent(void)
-{
-	dec_preempt_count();
-	preempt_check_resched();
-}
-
 void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
 		       unsigned long vaddr, void *dst, const void *src,
 		       unsigned long len)

arch/sh/mm/tlb-nommu.c

@@ -55,6 +55,21 @@ void __update_cache(struct vm_area_struct *vma,
 {
 }
 
+void __init kmap_coherent_init(void)
+{
+}
+
+void *kmap_coherent(struct page *page, unsigned long addr)
+{
+	BUG();
+	return NULL;
+}
+
+void kunmap_coherent(void)
+{
+	BUG();
+}
+
 void __init page_table_range_init(unsigned long start, unsigned long end,
 				  pgd_t *pgd_base)
 {