[ARM] Set bit 4 on section mappings correctly depending on CPU

On some CPUs, bit 4 of section mappings means "update the
cache when written to".  On others, this bit is required to
be one, and others it's required to be zero.  Finally, on
ARMv6 and above, setting it turns on "no execute" and prevents
speculative prefetches.

With all these combinations, no one value fits all CPUs, so we
have to pick a value depending on the CPU type, and the area
we're mapping.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

16 files changed, 140 insertions, 17 deletions

diff --git a/arch/arm/mm/mm-armv.c b/arch/arm/mm/mm-armv.c
index 95273de..d06440c 100644
--- a/arch/arm/mm/mm-armv.c
+++ b/arch/arm/mm/mm-armv.c
@@ -303,16 +303,16 @@ static struct mem_types mem_types[] __initdata = {
 		.prot_pte  = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
 				L_PTE_WRITE,
 		.prot_l1   = PMD_TYPE_TABLE,
-		.prot_sect = PMD_TYPE_SECT | PMD_SECT_UNCACHED |
+		.prot_sect = PMD_TYPE_SECT | PMD_BIT4 | PMD_SECT_UNCACHED |
 				PMD_SECT_AP_WRITE,
 		.domain    = DOMAIN_IO,
 	},
 	[MT_CACHECLEAN] = {
-		.prot_sect = PMD_TYPE_SECT,
+		.prot_sect = PMD_TYPE_SECT | PMD_BIT4,
 		.domain    = DOMAIN_KERNEL,
 	},
 	[MT_MINICLEAN] = {
-		.prot_sect = PMD_TYPE_SECT | PMD_SECT_MINICACHE,
+		.prot_sect = PMD_TYPE_SECT | PMD_BIT4 | PMD_SECT_MINICACHE,
 		.domain    = DOMAIN_KERNEL,
 	},
 	[MT_LOW_VECTORS] = {
@@ -328,25 +328,25 @@ static struct mem_types mem_types[] __initdata = {
 		.domain    = DOMAIN_USER,
 	},
 	[MT_MEMORY] = {
-		.prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
+		.prot_sect = PMD_TYPE_SECT | PMD_BIT4 | PMD_SECT_AP_WRITE,
 		.domain    = DOMAIN_KERNEL,
 	},
 	[MT_ROM] = {
-		.prot_sect = PMD_TYPE_SECT,
+		.prot_sect = PMD_TYPE_SECT | PMD_BIT4,
 		.domain    = DOMAIN_KERNEL,
 	},
 	[MT_IXP2000_DEVICE] = { /* IXP2400 requires XCB=101 for on-chip I/O */
 		.prot_pte  = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
 				L_PTE_WRITE,
 		.prot_l1   = PMD_TYPE_TABLE,
-		.prot_sect = PMD_TYPE_SECT | PMD_SECT_UNCACHED |
+		.prot_sect = PMD_TYPE_SECT | PMD_BIT4 | PMD_SECT_UNCACHED |
 				PMD_SECT_AP_WRITE | PMD_SECT_BUFFERABLE |
 				PMD_SECT_TEX(1),
 		.domain    = DOMAIN_IO,
 	},
 	[MT_NONSHARED_DEVICE] = {
 		.prot_l1   = PMD_TYPE_TABLE,
-		.prot_sect = PMD_TYPE_SECT | PMD_SECT_NONSHARED_DEV |
+		.prot_sect = PMD_TYPE_SECT | PMD_BIT4 | PMD_SECT_NONSHARED_DEV |
 				PMD_SECT_AP_WRITE,
 		.domain    = DOMAIN_IO,
 	}
@@ -376,14 +376,21 @@ void __init build_mem_type_table(void)
 		ecc_mask = 0;
 	}
 
-	if (cpu_arch <= CPU_ARCH_ARMv5TEJ && !cpu_is_xscale()) {
-		for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
+	/*
+	 * Xscale must not have PMD bit 4 set for section mappings.
+	 */
+	if (cpu_is_xscale())
+		for (i = 0; i < ARRAY_SIZE(mem_types); i++)
+			mem_types[i].prot_sect &= ~PMD_BIT4;
+
+	/*
+	 * ARMv5 and lower, excluding Xscale, bit 4 must be set for
+	 * page tables.
+	 */
+	if (cpu_arch < CPU_ARCH_ARMv6 && !cpu_is_xscale())
+		for (i = 0; i < ARRAY_SIZE(mem_types); i++)
 			if (mem_types[i].prot_l1)
 				mem_types[i].prot_l1 |= PMD_BIT4;
-			if (mem_types[i].prot_sect)
-				mem_types[i].prot_sect |= PMD_BIT4;
-		}
-	}
 
 	cp = &cache_policies[cachepolicy];
 	kern_pgprot = user_pgprot = cp->pte;
@@ -407,8 +414,8 @@ void __init build_mem_type_table(void)
 		 * bit 4 becomes XN which we must clear for the
 		 * kernel memory mapping.
 		 */
-		mem_types[MT_MEMORY].prot_sect &= ~PMD_BIT4;
-		mem_types[MT_ROM].prot_sect &= ~PMD_BIT4;
+		mem_types[MT_MEMORY].prot_sect &= ~PMD_SECT_XN;
+		mem_types[MT_ROM].prot_sect &= ~PMD_SECT_XN;
 
 		/*
 		 * Mark cache clean areas and XIP ROM read only
diff --git a/arch/arm/mm/proc-arm1020.S b/arch/arm/mm/proc-arm1020.S
index b9abbaf..efeebe7 100644
--- a/arch/arm/mm/proc-arm1020.S
+++ b/arch/arm/mm/proc-arm1020.S
@@ -527,6 +527,9 @@ __arm1020_proc_info:
 	.long   PMD_TYPE_SECT | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b	__arm1020_setup
 	.long	cpu_arch_name
 	.long	cpu_elf_name
diff --git a/arch/arm/mm/proc-arm1020e.S b/arch/arm/mm/proc-arm1020e.S
index 8c7e25f..78622ac 100644
--- a/arch/arm/mm/proc-arm1020e.S
+++ b/arch/arm/mm/proc-arm1020e.S
@@ -492,6 +492,10 @@ __arm1020e_proc_info:
 		PMD_BIT4 | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_BIT4 | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b	__arm1020e_setup
 	.long	cpu_arch_name
 	.long	cpu_elf_name
diff --git a/arch/arm/mm/proc-arm1022.S b/arch/arm/mm/proc-arm1022.S
index 92218e6..840dfc8 100644
--- a/arch/arm/mm/proc-arm1022.S
+++ b/arch/arm/mm/proc-arm1022.S
@@ -475,6 +475,10 @@ __arm1022_proc_info:
 		PMD_BIT4 | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_BIT4 | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b	__arm1022_setup
 	.long	cpu_arch_name
 	.long	cpu_elf_name
diff --git a/arch/arm/mm/proc-arm1026.S b/arch/arm/mm/proc-arm1026.S
index 2796c8e..72b75d9 100644
--- a/arch/arm/mm/proc-arm1026.S
+++ b/arch/arm/mm/proc-arm1026.S
@@ -471,6 +471,10 @@ __arm1026_proc_info:
 		PMD_BIT4 | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_BIT4 | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b	__arm1026_setup
 	.long	cpu_arch_name
 	.long	cpu_elf_name
diff --git a/arch/arm/mm/proc-arm6_7.S b/arch/arm/mm/proc-arm6_7.S
index 7a705ed..0432e48 100644
--- a/arch/arm/mm/proc-arm6_7.S
+++ b/arch/arm/mm/proc-arm6_7.S
@@ -355,6 +355,10 @@ __arm6_proc_info:
 		.long	0x41560600
 		.long	0xfffffff0
 		.long	0x00000c1e
+		.long   PMD_TYPE_SECT | \
+			PMD_BIT4 | \
+			PMD_SECT_AP_WRITE | \
+			PMD_SECT_AP_READ
 		b	__arm6_setup
 		.long	cpu_arch_name
 		.long	cpu_elf_name
@@ -371,6 +375,10 @@ __arm610_proc_info:
 		.long	0x41560610
 		.long	0xfffffff0
 		.long	0x00000c1e
+		.long   PMD_TYPE_SECT | \
+			PMD_BIT4 | \
+			PMD_SECT_AP_WRITE | \
+			PMD_SECT_AP_READ
 		b	__arm6_setup
 		.long	cpu_arch_name
 		.long	cpu_elf_name
@@ -387,6 +395,10 @@ __arm7_proc_info:
 		.long	0x41007000
 		.long	0xffffff00
 		.long	0x00000c1e
+		.long   PMD_TYPE_SECT | \
+			PMD_BIT4 | \
+			PMD_SECT_AP_WRITE | \
+			PMD_SECT_AP_READ
 		b	__arm7_setup
 		.long	cpu_arch_name
 		.long	cpu_elf_name
@@ -408,6 +420,10 @@ __arm710_proc_info:
 			PMD_BIT4 | \
 			PMD_SECT_AP_WRITE | \
 			PMD_SECT_AP_READ
+		.long   PMD_TYPE_SECT | \
+			PMD_BIT4 | \
+			PMD_SECT_AP_WRITE | \
+			PMD_SECT_AP_READ
 		b	__arm7_setup
 		.long	cpu_arch_name
 		.long	cpu_elf_name
diff --git a/arch/arm/mm/proc-arm720.S b/arch/arm/mm/proc-arm720.S
index 8610246..fb4110a 100644
--- a/arch/arm/mm/proc-arm720.S
+++ b/arch/arm/mm/proc-arm720.S
@@ -246,6 +246,10 @@ __arm710_proc_info:
 			PMD_BIT4 | \
 			PMD_SECT_AP_WRITE | \
 			PMD_SECT_AP_READ
+		.long   PMD_TYPE_SECT | \
+			PMD_BIT4 | \
+			PMD_SECT_AP_WRITE | \
+			PMD_SECT_AP_READ
 		b	__arm710_setup				@ cpu_flush
 		.long	cpu_arch_name				@ arch_name
 		.long	cpu_elf_name				@ elf_name
@@ -267,6 +271,10 @@ __arm720_proc_info:
 			PMD_BIT4 | \
 			PMD_SECT_AP_WRITE | \
 			PMD_SECT_AP_READ
+		.long   PMD_TYPE_SECT | \
+			PMD_BIT4 | \
+			PMD_SECT_AP_WRITE | \
+			PMD_SECT_AP_READ
 		b	__arm720_setup				@ cpu_flush
 		.long	cpu_arch_name				@ arch_name
 		.long	cpu_elf_name				@ elf_name
diff --git a/arch/arm/mm/proc-arm920.S b/arch/arm/mm/proc-arm920.S
index 02af3e2..b9f1bd1 100644
--- a/arch/arm/mm/proc-arm920.S
+++ b/arch/arm/mm/proc-arm920.S
@@ -461,6 +461,10 @@ __arm920_proc_info:
 		PMD_BIT4 | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_BIT4 | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b	__arm920_setup
 	.long	cpu_arch_name
 	.long	cpu_elf_name
diff --git a/arch/arm/mm/proc-arm922.S b/arch/arm/mm/proc-arm922.S
index 33dae49..bda0aea 100644
--- a/arch/arm/mm/proc-arm922.S
+++ b/arch/arm/mm/proc-arm922.S
@@ -465,6 +465,10 @@ __arm922_proc_info:
 		PMD_BIT4 | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_BIT4 | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b	__arm922_setup
 	.long	cpu_arch_name
 	.long	cpu_elf_name
diff --git a/arch/arm/mm/proc-arm925.S b/arch/arm/mm/proc-arm925.S
index aaa9f98..a28da8f 100644
--- a/arch/arm/mm/proc-arm925.S
+++ b/arch/arm/mm/proc-arm925.S
@@ -526,6 +526,10 @@ __arm925_proc_info:
 		PMD_BIT4 | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_BIT4 | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b	__arm925_setup
 	.long	cpu_arch_name
 	.long	cpu_elf_name
@@ -545,6 +549,10 @@ __arm915_proc_info:
 		PMD_BIT4 | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_BIT4 | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b	__arm925_setup
 	.long	cpu_arch_name
 	.long	cpu_elf_name
diff --git a/arch/arm/mm/proc-arm926.S b/arch/arm/mm/proc-arm926.S
index ce246dd..496a233 100644
--- a/arch/arm/mm/proc-arm926.S
+++ b/arch/arm/mm/proc-arm926.S
@@ -477,6 +477,10 @@ __arm926_proc_info:
 		PMD_BIT4 | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_BIT4 | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b	__arm926_setup
 	.long	cpu_arch_name
 	.long	cpu_elf_name
diff --git a/arch/arm/mm/proc-sa110.S b/arch/arm/mm/proc-sa110.S
index 5a760a2..31a0908 100644
--- a/arch/arm/mm/proc-sa110.S
+++ b/arch/arm/mm/proc-sa110.S
@@ -255,6 +255,9 @@ __sa110_proc_info:
 		PMD_SECT_CACHEABLE | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b	__sa110_setup
 	.long	cpu_arch_name
 	.long	cpu_elf_name
diff --git a/arch/arm/mm/proc-sa1100.S b/arch/arm/mm/proc-sa1100.S
index 0a2107a..4e2489c 100644
--- a/arch/arm/mm/proc-sa1100.S
+++ b/arch/arm/mm/proc-sa1100.S
@@ -276,6 +276,9 @@ __sa1100_proc_info:
 		PMD_SECT_CACHEABLE | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b	__sa1100_setup
 	.long	cpu_arch_name
 	.long	cpu_elf_name
@@ -296,6 +299,9 @@ __sa1110_proc_info:
 		PMD_SECT_CACHEABLE | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b	__sa1100_setup
 	.long	cpu_arch_name
 	.long	cpu_elf_name
diff --git a/arch/arm/mm/proc-v6.S b/arch/arm/mm/proc-v6.S
index ca13d4d..ff77896 100644
--- a/arch/arm/mm/proc-v6.S
+++ b/arch/arm/mm/proc-v6.S
@@ -269,6 +269,10 @@ __v6_proc_info:
 		PMD_SECT_CACHEABLE | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_SECT_XN | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b	__v6_setup
 	.long	cpu_arch_name
 	.long	cpu_elf_name
diff --git a/arch/arm/mm/proc-xsc3.S b/arch/arm/mm/proc-xsc3.S
index 8d32e21..9aea506 100644
--- a/arch/arm/mm/proc-xsc3.S
+++ b/arch/arm/mm/proc-xsc3.S
@@ -487,7 +487,14 @@ cpu_xsc3_name:
 __xsc3_proc_info:
 	.long	0x69056000
 	.long	0xffffe000
-	.long	0x00000c0e
+	.long	PMD_TYPE_SECT | \
+		PMD_SECT_BUFFERABLE | \
+		PMD_SECT_CACHEABLE | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b	__xsc3_setup
 	.long	cpu_arch_name
 	.long	cpu_elf_name
diff --git a/arch/arm/mm/proc-xscale.S b/arch/arm/mm/proc-xscale.S
index 29bcc4d..f4aeb7b 100644
--- a/arch/arm/mm/proc-xscale.S
+++ b/arch/arm/mm/proc-xscale.S
@@ -595,6 +595,9 @@ __80200_proc_info:
 		PMD_SECT_CACHEABLE | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b	__xscale_setup
 	.long	cpu_arch_name
 	.long	cpu_elf_name
@@ -615,6 +618,9 @@ __8032x_proc_info:
 		PMD_SECT_CACHEABLE | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b	__xscale_setup
 	.long	cpu_arch_name
 	.long	cpu_elf_name
@@ -635,6 +641,9 @@ __8033x_proc_info:
 		PMD_SECT_CACHEABLE | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b	__xscale_setup
 	.long	cpu_arch_name
 	.long	cpu_elf_name
@@ -655,6 +664,9 @@ __pxa250_proc_info:
 		PMD_SECT_CACHEABLE | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b	__xscale_setup
 	.long	cpu_arch_name
 	.long	cpu_elf_name
@@ -675,6 +687,9 @@ __pxa210_proc_info:
 		PMD_SECT_CACHEABLE | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b	__xscale_setup
 	.long	cpu_arch_name
 	.long	cpu_elf_name
@@ -695,6 +710,9 @@ __ixp2400_proc_info:
 		PMD_SECT_CACHEABLE | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b       __xscale_setup
 	.long   cpu_arch_name
 	.long   cpu_elf_name
@@ -715,6 +733,9 @@ __ixp2800_proc_info:
 		PMD_SECT_CACHEABLE | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b       __xscale_setup
 	.long   cpu_arch_name
 	.long   cpu_elf_name
@@ -735,6 +756,9 @@ __ixp42x_proc_info:
 		PMD_SECT_CACHEABLE | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b       __xscale_setup
 	.long   cpu_arch_name
 	.long   cpu_elf_name
@@ -750,7 +774,14 @@ __ixp42x_proc_info:
 __ixp46x_proc_info:
 	.long   0x69054200
 	.long   0xffffff00
-	.long   0x00000c0e
+	.long   PMD_TYPE_SECT | \
+		PMD_SECT_BUFFERABLE | \
+		PMD_SECT_CACHEABLE | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b       __xscale_setup
 	.long   cpu_arch_name
 	.long   cpu_elf_name
@@ -771,6 +802,9 @@ __pxa255_proc_info:
 		PMD_SECT_CACHEABLE | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b	__xscale_setup
 	.long	cpu_arch_name
 	.long	cpu_elf_name
@@ -791,6 +825,9 @@ __pxa270_proc_info:
 		PMD_SECT_CACHEABLE | \
 		PMD_SECT_AP_WRITE | \
 		PMD_SECT_AP_READ
+	.long   PMD_TYPE_SECT | \
+		PMD_SECT_AP_WRITE | \
+		PMD_SECT_AP_READ
 	b	__xscale_setup
 	.long	cpu_arch_name
 	.long	cpu_elf_name