Merge branch 'for-next/arm'

5 files changed, 60 insertions, 11 deletions

diff --git a/arch/arm/cpu/cache-armv7.S b/arch/arm/cpu/cache-armv7.S
index 7a1c5c0189..6a8aff8bb1 100644
--- a/arch/arm/cpu/cache-armv7.S
+++ b/arch/arm/cpu/cache-armv7.S
@@ -83,7 +83,10 @@ hierarchical:
 		ands	r3, r0, #0x7000000	@ extract loc from clidr
 		mov	r3, r3, lsr #23		@ left align loc bit field
 		beq	finished		@ if loc is 0, then no need to clean
-		mov	r12, #0			@ start clean at cache level 0
+		cmp	r8, #0
+THUMB(		ite	eq			)
+		moveq	r12, #0
+		subne	r12, r3, #2		@ start invalidate at outmost cache level
 loop1:
 		add	r2, r12, r12, lsr #1	@ work out 3x current cache level
 		mov	r1, r0, lsr r2		@ extract cache type bits from clidr
@@ -118,8 +121,16 @@ THUMB(		ite	eq			)
 		subs	r7, r7, #1		@ decrement the index
 		bge	loop2
 skip:
+		cmp	r8, #0
+		bne	inval_check
 		add	r12, r12, #2		@ increment cache number
 		cmp	r3, r12
+		b	loop_end_check
+inval_check:
+		cmp	r12, #0
+		sub	r12, r12, #2		@ decrement cache number
+loop_end_check:
+		dsb				@ work-around Cortex-A7 erratum 814220
 		bgt	loop1
 finished:
 		ldmfd	sp!, {r4-r11}
diff --git a/arch/arm/cpu/lowlevel_64.S b/arch/arm/cpu/lowlevel_64.S
index af1cd8b5bc..6a23132ed1 100644
--- a/arch/arm/cpu/lowlevel_64.S
+++ b/arch/arm/cpu/lowlevel_64.S
@@ -12,6 +12,13 @@ ENTRY(arm_cpu_lowlevel_init)
 	orr	x0, x0, #(1 << 10)	/* 64-bit EL2 */
 	msr	scr_el3, x0
 	msr	cptr_el3, xzr
+
+	mrs	x0, sctlr_el3
+	ldr	x1, =SCTLR_ELx_FLAGS
+	bic	x0, x0, x1
+	msr	sctlr_el3, x0
+	isb
+
 	b	done
 
 2:
diff --git a/arch/arm/cpu/mmu-early.c b/arch/arm/cpu/mmu-early.c
index d39a03ed95..2f5876fc46 100644
--- a/arch/arm/cpu/mmu-early.c
+++ b/arch/arm/cpu/mmu-early.c
@@ -5,17 +5,20 @@
 #include <asm/memory.h>
 #include <asm/system.h>
 #include <asm/cache.h>
+#include <asm-generic/sections.h>
 
 #include "mmu.h"
 
 static uint32_t *ttb;
 
-static void map_cachable(unsigned long start, unsigned long size)
+static inline void map_region(unsigned long start, unsigned long size,
+			      uint64_t flags)
+
 {
 	start = ALIGN_DOWN(start, SZ_1M);
 	size  = ALIGN(size, SZ_1M);
 
-	create_sections(ttb, start, start + size - 1, PMD_SECT_DEF_CACHED);
+	create_sections(ttb, start, start + size - 1, flags);
 }
 
 void mmu_early_enable(unsigned long membase, unsigned long memsize,
@@ -28,9 +31,27 @@ void mmu_early_enable(unsigned long membase, unsigned long memsize,
 	set_ttbr(ttb);
 	set_domain(DOMAIN_MANAGER);
 
+	/*
+	 * This marks the whole address space as uncachable as well as
+	 * unexecutable if possible
+	 */
 	create_flat_mapping(ttb);
 
-	map_cachable(membase, memsize);
+	/*
+	 * There can be SoCs that have a section shared between device memory
+	 * and the on-chip RAM hosting the PBL. Thus mark this section
+	 * uncachable, but executable.
+	 * On such SoCs, executing from OCRAM could cause the instruction
+	 * prefetcher to speculatively access that device memory, triggering
+	 * potential errant behavior.
+	 *
+	 * If your SoC has such a memory layout, you should rewrite the code
+	 * here to map the OCRAM page-wise.
+	 */
+	map_region((unsigned long)_stext, _etext - _stext, PMD_SECT_DEF_UNCACHED);
+
+	/* maps main memory as cachable */
+	map_region(membase, memsize, PMD_SECT_DEF_CACHED);
 
 	__mmu_cache_on();
 }
diff --git a/arch/arm/cpu/mmu.c b/arch/arm/cpu/mmu.c
index 29816ad563..123e19e9e5 100644
--- a/arch/arm/cpu/mmu.c
+++ b/arch/arm/cpu/mmu.c
@@ -34,7 +34,6 @@
 
 #include "mmu.h"
 
-#define PMD_SECT_DEF_CACHED (PMD_SECT_WB | PMD_SECT_DEF_UNCACHED)
 #define PTRS_PER_PTE		(PGDIR_SIZE / PAGE_SIZE)
 #define ARCH_MAP_WRITECOMBINE	((unsigned)-1)
 
@@ -58,11 +57,13 @@ static inline void tlb_invalidate(void)
 }
 
 #define PTE_FLAGS_CACHED_V7 (PTE_EXT_TEX(1) | PTE_BUFFERABLE | PTE_CACHEABLE)
-#define PTE_FLAGS_WC_V7 PTE_EXT_TEX(1)
-#define PTE_FLAGS_UNCACHED_V7 (0)
+#define PTE_FLAGS_WC_V7 (PTE_EXT_TEX(1) | PTE_EXT_XN)
+#define PTE_FLAGS_UNCACHED_V7 PTE_EXT_XN
 #define PTE_FLAGS_CACHED_V4 (PTE_SMALL_AP_UNO_SRW | PTE_BUFFERABLE | PTE_CACHEABLE)
 #define PTE_FLAGS_UNCACHED_V4 PTE_SMALL_AP_UNO_SRW
-#define PGD_FLAGS_WC_V7 (PMD_SECT_TEX(1) | PMD_TYPE_SECT | PMD_SECT_BUFFERABLE)
+#define PGD_FLAGS_WC_V7 (PMD_SECT_TEX(1) | PMD_TYPE_SECT | PMD_SECT_BUFFERABLE | \
+			 PMD_SECT_XN)
+#define PGD_FLAGS_UNCACHED_V7 (PMD_SECT_DEF_UNCACHED | PMD_SECT_XN)
 
 /*
  * PTE flags to set cached and uncached areas.
@@ -72,6 +73,7 @@ static uint32_t pte_flags_cached;
 static uint32_t pte_flags_wc;
 static uint32_t pte_flags_uncached;
 static uint32_t pgd_flags_wc;
+static uint32_t pgd_flags_uncached;
 
 #define PTE_MASK ((1 << 12) - 1)
 
@@ -164,7 +166,7 @@ int arch_remap_range(void *start, size_t size, unsigned flags)
 		break;
 	case MAP_UNCACHED:
 		pte_flags = pte_flags_uncached;
-		pgd_flags = PMD_SECT_DEF_UNCACHED;
+		pgd_flags = pgd_flags_uncached;
 		break;
 	case ARCH_MAP_WRITECOMBINE:
 		pte_flags = pte_flags_wc;
@@ -247,7 +249,7 @@ void *map_io_sections(unsigned long phys, void *_start, size_t size)
 	unsigned long start = (unsigned long)_start, sec;
 
 	for (sec = start; sec < start + size; sec += PGDIR_SIZE, phys += PGDIR_SIZE)
-		ttb[pgd_index(sec)] = phys | PMD_SECT_DEF_UNCACHED;
+		ttb[pgd_index(sec)] = phys | pgd_flags_uncached;
 
 	dma_flush_range(ttb, 0x4000);
 	tlb_invalidate();
@@ -411,11 +413,13 @@ void __mmu_init(bool mmu_on)
 		pte_flags_cached = PTE_FLAGS_CACHED_V7;
 		pte_flags_wc = PTE_FLAGS_WC_V7;
 		pgd_flags_wc = PGD_FLAGS_WC_V7;
+		pgd_flags_uncached = PGD_FLAGS_UNCACHED_V7;
 		pte_flags_uncached = PTE_FLAGS_UNCACHED_V7;
 	} else {
 		pte_flags_cached = PTE_FLAGS_CACHED_V4;
 		pte_flags_wc = PTE_FLAGS_UNCACHED_V4;
 		pgd_flags_wc = PMD_SECT_DEF_UNCACHED;
+		pgd_flags_uncached = PMD_SECT_DEF_UNCACHED;
 		pte_flags_uncached = PTE_FLAGS_UNCACHED_V4;
 	}
 
diff --git a/arch/arm/cpu/mmu.h b/arch/arm/cpu/mmu.h
index 338728aacd..c911ee209f 100644
--- a/arch/arm/cpu/mmu.h
+++ b/arch/arm/cpu/mmu.h
@@ -3,6 +3,7 @@
 
 #include <asm/pgtable.h>
 #include <linux/sizes.h>
+#include <asm/system_info.h>
 
 #include "mmu-common.h"
 
@@ -62,8 +63,13 @@ create_sections(uint32_t *ttb, unsigned long first,
 
 static inline void create_flat_mapping(uint32_t *ttb)
 {
+	unsigned int flags = PMD_SECT_DEF_UNCACHED;
+
+	if (cpu_architecture() >= CPU_ARCH_ARMv7)
+		flags |= PMD_SECT_XN;
+
 	/* create a flat mapping using 1MiB sections */
-	create_sections(ttb, 0, 0xffffffff, PMD_SECT_DEF_UNCACHED);
+	create_sections(ttb, 0, 0xffffffff, flags);
 }
 
 #endif /* __ARM_MMU_H */