arm: Add control over cachability of memory regions

[karo-tx-uboot.git] / arch / arm / lib / cache-cp15.c

diff --git a/arch/arm/lib/cache-cp15.c b/arch/arm/lib/cache-cp15.c
index 939de10e039153d0fd1ef29cb962366d5357a355..6edf815d4d7b85f9b6197260b9b870acb01b586f 100644 (file)
--- a/arch/arm/lib/cache-cp15.c
+++ b/arch/arm/lib/cache-cp15.c
@@ -26,12 +26,6 @@
 
 #if !(defined(CONFIG_SYS_ICACHE_OFF) && defined(CONFIG_SYS_DCACHE_OFF))
 
-#if defined(CONFIG_SYS_ARM_CACHE_WRITETHROUGH)
-#define CACHE_SETUP    0x1a
-#else
-#define CACHE_SETUP    0x1e
-#endif
-
 DECLARE_GLOBAL_DATA_PTR;
 
 void __arm_init_before_mmu(void)
@@ -50,9 +44,41 @@ static void cp_delay (void)
        asm volatile("" : : : "memory");
 }
 
-static inline void dram_bank_mmu_setup(int bank)
+void set_section_dcache(int section, enum dcache_option option)
 {
        u32 *page_table = (u32 *)gd->tlb_addr;
+       u32 value;
+
+       value = (section << MMU_SECTION_SHIFT) | (3 << 10);
+       value |= option;
+       page_table[section] = value;
+}
+
+void __mmu_page_table_flush(unsigned long start, unsigned long stop)
+{
+       debug("%s: Warning: not implemented\n", __func__);
+}
+
+void mmu_page_table_flush(unsigned long start, unsigned long stop)
+       __attribute__((weak, alias("__mmu_page_table_flush")));
+
+void mmu_set_region_dcache_behaviour(u32 start, int size,
+                                    enum dcache_option option)
+{
+       u32 *page_table = (u32 *)gd->tlb_addr;
+       u32 upto, end;
+
+       end = ALIGN(start + size, MMU_SECTION_SIZE) >> MMU_SECTION_SHIFT;
+       start = start >> MMU_SECTION_SHIFT;
+       debug("%s: start=%x, size=%x, option=%d\n", __func__, start, size,
+             option);
+       for (upto = start; upto < end; upto++)
+               set_section_dcache(upto, option);
+       mmu_page_table_flush((u32)&page_table[start], (u32)&page_table[end]);
+}
+
+static inline void dram_bank_mmu_setup(int bank)
+{
        bd_t *bd = gd->bd;
        int     i;
 
@@ -60,21 +86,24 @@ static inline void dram_bank_mmu_setup(int bank)
        for (i = bd->bi_dram[bank].start >> 20;
             i < (bd->bi_dram[bank].start + bd->bi_dram[bank].size) >> 20;
             i++) {
-               page_table[i] = i << 20 | (3 << 10) | CACHE_SETUP;
+#if defined(CONFIG_SYS_ARM_CACHE_WRITETHROUGH)
+               set_section_dcache(i, DCACHE_WRITETHROUGH);
+#else
+               set_section_dcache(i, DCACHE_WRITEBACK);
+#endif
        }
 }
 
 /* to activate the MMU we need to set up virtual memory: use 1M areas */
 static inline void mmu_setup(void)
 {
-       u32 *page_table = (u32 *)gd->tlb_addr;
        int i;
        u32 reg;
 
        arm_init_before_mmu();
        /* Set up an identity-mapping for all 4GB, rw for everyone */
        for (i = 0; i < 4096; i++)
-               page_table[i] = i << 20 | (3 << 10) | 0x12;
+               set_section_dcache(i, DCACHE_OFF);
 
        for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
                dram_bank_mmu_setup(i);
@@ -82,7 +111,7 @@ static inline void mmu_setup(void)
 
        /* Copy the page table address to cp15 */
        asm volatile("mcr p15, 0, %0, c2, c0, 0"
-                    : : "r" (page_table) : "memory");
+                    : : "r" (gd->tlb_addr) : "memory");
        /* Set the access control to all-supervisor */
        asm volatile("mcr p15, 0, %0, c3, c0, 0"
                     : : "r" (~0));