arm: Add support for HYP mode and LPAE page tables

We currently always modify the SVC versions of registers and only support
the short descriptor PTE format.

Some boards however (like the RPi2) run in HYP mode. There, we need to modify
the HYP version of system registers and HYP mode only supports the long
descriptor PTE format.

So this patch introduces support for both long descriptor PTEs and HYP mode
registers.

Signed-off-by: Alexander Graf <agraf@suse.de>

1 files changed, 60 insertions, 6 deletions

diff --git a/arch/arm/lib/cache-cp15.c b/arch/arm/lib/cache-cp15.c
index 8e18538..1121dc3 100644
--- a/arch/arm/lib/cache-cp15.c
+++ b/arch/arm/lib/cache-cp15.c
@@ -34,11 +34,22 @@ static void cp_delay (void)
 
 void set_section_dcache(int section, enum dcache_option option)
 {
+#ifdef CONFIG_ARMV7_LPAE
+	u64 *page_table = (u64 *)gd->arch.tlb_addr;
+	/* Need to set the access flag to not fault */
+	u64 value = TTB_SECT_AP | TTB_SECT_AF;
+#else
 	u32 *page_table = (u32 *)gd->arch.tlb_addr;
-	u32 value;
+	u32 value = TTB_SECT_AP;
+#endif
+
+	/* Add the page offset */
+	value |= ((u32)section << MMU_SECTION_SHIFT);
 
-	value = (section << MMU_SECTION_SHIFT) | (3 << 10);
+	/* Add caching bits */
 	value |= option;
+
+	/* Set PTE */
 	page_table[section] = value;
 }
 
@@ -68,8 +79,9 @@ __weak void dram_bank_mmu_setup(int bank)
 	int	i;
 
 	debug("%s: bank: %d\n", __func__, bank);
-	for (i = bd->bi_dram[bank].start >> 20;
-	     i < (bd->bi_dram[bank].start >> 20) + (bd->bi_dram[bank].size >> 20);
+	for (i = bd->bi_dram[bank].start >> MMU_SECTION_SHIFT;
+	     i < (bd->bi_dram[bank].start >> MMU_SECTION_SHIFT) +
+		 (bd->bi_dram[bank].size >> MMU_SECTION_SHIFT);
 	     i++) {
 #if defined(CONFIG_SYS_ARM_CACHE_WRITETHROUGH)
 		set_section_dcache(i, DCACHE_WRITETHROUGH);
@@ -89,14 +101,56 @@ static inline void mmu_setup(void)
 
 	arm_init_before_mmu();
 	/* Set up an identity-mapping for all 4GB, rw for everyone */
-	for (i = 0; i < 4096; i++)
+	for (i = 0; i < ((4096ULL * 1024 * 1024) >> MMU_SECTION_SHIFT); i++)
 		set_section_dcache(i, DCACHE_OFF);
 
 	for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
 		dram_bank_mmu_setup(i);
 	}
 
-#ifdef CONFIG_CPU_V7
+#ifdef CONFIG_ARMV7_LPAE
+	/* Set up 4 PTE entries pointing to our 4 1GB page tables */
+	for (i = 0; i < 4; i++) {
+		u64 *page_table = (u64 *)(gd->arch.tlb_addr + (4096 * 4));
+		u64 tpt = gd->arch.tlb_addr + (4096 * i);
+		page_table[i] = tpt | TTB_PAGETABLE;
+	}
+
+	reg = TTBCR_EAE;
+#if defined(CONFIG_SYS_ARM_CACHE_WRITETHROUGH)
+	reg |= TTBCR_ORGN0_WT | TTBCR_IRGN0_WT;
+#elif defined(CONFIG_SYS_ARM_CACHE_WRITEALLOC)
+	reg |= TTBCR_ORGN0_WBWA | TTBCR_IRGN0_WBWA;
+#else
+	reg |= TTBCR_ORGN0_WBNWA | TTBCR_IRGN0_WBNWA;
+#endif
+
+	if (is_hyp()) {
+		/* Set HCTR to enable LPAE */
+		asm volatile("mcr p15, 4, %0, c2, c0, 2"
+			: : "r" (reg) : "memory");
+		/* Set HTTBR0 */
+		asm volatile("mcrr p15, 4, %0, %1, c2"
+			:
+			: "r"(gd->arch.tlb_addr + (4096 * 4)), "r"(0)
+			: "memory");
+		/* Set HMAIR */
+		asm volatile("mcr p15, 4, %0, c10, c2, 0"
+			: : "r" (MEMORY_ATTRIBUTES) : "memory");
+	} else {
+		/* Set TTBCR to enable LPAE */
+		asm volatile("mcr p15, 0, %0, c2, c0, 2"
+			: : "r" (reg) : "memory");
+		/* Set 64-bit TTBR0 */
+		asm volatile("mcrr p15, 0, %0, %1, c2"
+			:
+			: "r"(gd->arch.tlb_addr + (4096 * 4)), "r"(0)
+			: "memory");
+		/* Set MAIR */
+		asm volatile("mcr p15, 0, %0, c10, c2, 0"
+			: : "r" (MEMORY_ATTRIBUTES) : "memory");
+	}
+#elif defined(CONFIG_CPU_V7)
 	/* Set TTBR0 */
 	reg = gd->arch.tlb_addr & TTBR0_BASE_ADDR_MASK;
 #if defined(CONFIG_SYS_ARM_CACHE_WRITETHROUGH)