X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=arch%2Farm%2Flib%2Fcache-cp15.c;h=939de10e039153d0fd1ef29cb962366d5357a355;hb=c2b3dcc24d80cd40b0e83bd169e787303c4055cc;hp=62ed54fb4d667b96bb054f56e064c46a3fc93823;hpb=83653121d7382fccfe329cb732f77f116341ef1d;p=oweals%2Fu-boot.git

diff --git a/arch/arm/lib/cache-cp15.c b/arch/arm/lib/cache-cp15.c
index 62ed54fb4d..939de10e03 100644
--- a/arch/arm/lib/cache-cp15.c
+++ b/arch/arm/lib/cache-cp15.c
@@ -24,7 +24,22 @@
 #include <common.h>
 #include <asm/system.h>
 
-#if !(defined(CONFIG_SYS_NO_ICACHE) && defined(CONFIG_SYS_NO_DCACHE))
+#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)
+{
+}
+void arm_init_before_mmu(void)
+	__attribute__((weak, alias("__arm_init_before_mmu")));
+
 static void cp_delay (void)
 {
 	volatile int i;
@@ -32,6 +47,54 @@ static void cp_delay (void)
 	/* copro seems to need some delay between reading and writing */
 	for (i = 0; i < 100; i++)
 		nop();
+	asm volatile("" : : : "memory");
+}
+
+static inline void dram_bank_mmu_setup(int bank)
+{
+	u32 *page_table = (u32 *)gd->tlb_addr;
+	bd_t *bd = gd->bd;
+	int	i;
+
+	debug("%s: bank: %d\n", __func__, 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;
+	}
+}
+
+/* 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;
+
+	for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
+		dram_bank_mmu_setup(i);
+	}
+
+	/* Copy the page table address to cp15 */
+	asm volatile("mcr p15, 0, %0, c2, c0, 0"
+		     : : "r" (page_table) : "memory");
+	/* Set the access control to all-supervisor */
+	asm volatile("mcr p15, 0, %0, c3, c0, 0"
+		     : : "r" (~0));
+	/* and enable the mmu */
+	reg = get_cr();	/* get control reg. */
+	cp_delay();
+	set_cr(reg | CR_M);
+}
+
+static int mmu_enabled(void)
+{
+	return get_cr() & CR_M;
 }
 
 /* cache_bit must be either CR_I or CR_C */
@@ -39,6 +102,9 @@ static void cache_enable(uint32_t cache_bit)
 {
 	uint32_t reg;
 
+	/* The data cache is not active unless the mmu is enabled too */
+	if ((cache_bit == CR_C) && !mmu_enabled())
+		mmu_setup();
 	reg = get_cr();	/* get control reg. */
 	cp_delay();
 	set_cr(reg | cache_bit);
@@ -51,11 +117,20 @@ static void cache_disable(uint32_t cache_bit)
 
 	reg = get_cr();
 	cp_delay();
+
+	if (cache_bit == CR_C) {
+		/* if cache isn;t enabled no need to disable */
+		if ((reg & CR_C) != CR_C)
+			return;
+		/* if disabling data cache, disable mmu too */
+		cache_bit |= CR_M;
+		flush_dcache_all();
+	}
 	set_cr(reg & ~cache_bit);
 }
 #endif
 
-#ifdef CONFIG_SYS_NO_ICACHE
+#ifdef CONFIG_SYS_ICACHE_OFF
 void icache_enable (void)
 {
 	return;
@@ -87,7 +162,7 @@ int icache_status(void)
 }
 #endif
 
-#ifdef CONFIG_SYS_NO_DCACHE
+#ifdef CONFIG_SYS_DCACHE_OFF
 void dcache_enable (void)
 {
 	return;