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-rw-r--r--arch/arm/kernel/head.S73
1 files changed, 63 insertions, 10 deletions
diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index 08c82fd844a8..6d5791144066 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S
@@ -39,8 +39,14 @@
#error KERNEL_RAM_VADDR must start at 0xXXXX8000
#endif
+#ifdef CONFIG_ARM_LPAE
+ /* LPAE requires an additional page for the PGD */
+#define PG_DIR_SIZE 0x5000
+#define PMD_ORDER 3
+#else
#define PG_DIR_SIZE 0x4000
#define PMD_ORDER 2
+#endif
.globl swapper_pg_dir
.equ swapper_pg_dir, KERNEL_RAM_VADDR - PG_DIR_SIZE
@@ -93,6 +99,14 @@ ENTRY(stext)
THUMB( it eq ) @ force fixup-able long branch encoding
beq __error_p @ yes, error 'p'
+#ifdef CONFIG_ARM_LPAE
+ mrc p15, 0, r3, c0, c1, 4 @ read ID_MMFR0
+ and r3, r3, #0xf @ extract VMSA support
+ cmp r3, #5 @ long-descriptor translation table format?
+ THUMB( it lo ) @ force fixup-able long branch encoding
+ blo __error_p @ only classic page table format
+#endif
+
#ifndef CONFIG_XIP_KERNEL
adr r3, 2f
ldmia r3, {r4, r8}
@@ -164,17 +178,36 @@ __create_page_tables:
teq r0, r6
bne 1b
+#ifdef CONFIG_ARM_LPAE
+ /*
+ * Build the PGD table (first level) to point to the PMD table. A PGD
+ * entry is 64-bit wide.
+ */
+ mov r0, r4
+ add r3, r4, #0x1000 @ first PMD table address
+ orr r3, r3, #3 @ PGD block type
+ mov r6, #4 @ PTRS_PER_PGD
+ mov r7, #1 << (55 - 32) @ L_PGD_SWAPPER
+1: str r3, [r0], #4 @ set bottom PGD entry bits
+ str r7, [r0], #4 @ set top PGD entry bits
+ add r3, r3, #0x1000 @ next PMD table
+ subs r6, r6, #1
+ bne 1b
+
+ add r4, r4, #0x1000 @ point to the PMD tables
+#endif
+
ldr r7, [r10, #PROCINFO_MM_MMUFLAGS] @ mm_mmuflags
/*
* Create identity mapping to cater for __enable_mmu.
* This identity mapping will be removed by paging_init().
*/
- adr r0, __enable_mmu_loc
+ adr r0, __turn_mmu_on_loc
ldmia r0, {r3, r5, r6}
sub r0, r0, r3 @ virt->phys offset
- add r5, r5, r0 @ phys __enable_mmu
- add r6, r6, r0 @ phys __enable_mmu_end
+ add r5, r5, r0 @ phys __turn_mmu_on
+ add r6, r6, r0 @ phys __turn_mmu_on_end
mov r5, r5, lsr #SECTION_SHIFT
mov r6, r6, lsr #SECTION_SHIFT
@@ -219,8 +252,8 @@ __create_page_tables:
#endif
/*
- * Then map boot params address in r2 or
- * the first 1MB of ram if boot params address is not specified.
+ * Then map boot params address in r2 or the first 1MB (2MB with LPAE)
+ * of ram if boot params address is not specified.
*/
mov r0, r2, lsr #SECTION_SHIFT
movs r0, r0, lsl #SECTION_SHIFT
@@ -251,7 +284,15 @@ __create_page_tables:
mov r3, r7, lsr #SECTION_SHIFT
ldr r7, [r10, #PROCINFO_IO_MMUFLAGS] @ io_mmuflags
orr r3, r7, r3, lsl #SECTION_SHIFT
+#ifdef CONFIG_ARM_LPAE
+ mov r7, #1 << (54 - 32) @ XN
+#else
+ orr r3, r3, #PMD_SECT_XN
+#endif
1: str r3, [r0], #4
+#ifdef CONFIG_ARM_LPAE
+ str r7, [r0], #4
+#endif
add r3, r3, #1 << SECTION_SHIFT
cmp r0, r6
blo 1b
@@ -283,14 +324,17 @@ __create_page_tables:
str r3, [r0]
#endif
#endif
+#ifdef CONFIG_ARM_LPAE
+ sub r4, r4, #0x1000 @ point to the PGD table
+#endif
mov pc, lr
ENDPROC(__create_page_tables)
.ltorg
.align
-__enable_mmu_loc:
+__turn_mmu_on_loc:
.long .
- .long __enable_mmu
- .long __enable_mmu_end
+ .long __turn_mmu_on
+ .long __turn_mmu_on_end
#if defined(CONFIG_SMP)
__CPUINIT
@@ -374,12 +418,17 @@ __enable_mmu:
#ifdef CONFIG_CPU_ICACHE_DISABLE
bic r0, r0, #CR_I
#endif
+#ifdef CONFIG_ARM_LPAE
+ mov r5, #0
+ mcrr p15, 0, r4, r5, c2 @ load TTBR0
+#else
mov r5, #(domain_val(DOMAIN_USER, DOMAIN_MANAGER) | \
domain_val(DOMAIN_KERNEL, DOMAIN_MANAGER) | \
domain_val(DOMAIN_TABLE, DOMAIN_MANAGER) | \
domain_val(DOMAIN_IO, DOMAIN_CLIENT))
mcr p15, 0, r5, c3, c0, 0 @ load domain access register
mcr p15, 0, r4, c2, c0, 0 @ load page table pointer
+#endif
b __turn_mmu_on
ENDPROC(__enable_mmu)
@@ -398,15 +447,19 @@ ENDPROC(__enable_mmu)
* other registers depend on the function called upon completion
*/
.align 5
-__turn_mmu_on:
+ .pushsection .idmap.text, "ax"
+ENTRY(__turn_mmu_on)
mov r0, r0
+ instr_sync
mcr p15, 0, r0, c1, c0, 0 @ write control reg
mrc p15, 0, r3, c0, c0, 0 @ read id reg
+ instr_sync
mov r3, r3
mov r3, r13
mov pc, r3
-__enable_mmu_end:
+__turn_mmu_on_end:
ENDPROC(__turn_mmu_on)
+ .popsection
#ifdef CONFIG_SMP_ON_UP