diff options
Diffstat (limited to 'arch/arm/kernel/head.S')
-rw-r--r-- | arch/arm/kernel/head.S | 54 |
1 files changed, 15 insertions, 39 deletions
diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S index dd5d0f07d358..8d8748407cbe 100644 --- a/arch/arm/kernel/head.S +++ b/arch/arm/kernel/head.S | |||
@@ -34,52 +34,28 @@ | |||
34 | #define MACHINFO_PGOFFIO 12 | 34 | #define MACHINFO_PGOFFIO 12 |
35 | #define MACHINFO_NAME 16 | 35 | #define MACHINFO_NAME 16 |
36 | 36 | ||
37 | #ifndef CONFIG_XIP_KERNEL | ||
38 | /* | 37 | /* |
39 | * We place the page tables 16K below TEXTADDR. Therefore, we must make sure | 38 | * swapper_pg_dir is the virtual address of the initial page table. |
40 | * that TEXTADDR is correctly set. Currently, we expect the least significant | 39 | * We place the page tables 16K below KERNEL_RAM_ADDR. Therefore, we must |
41 | * 16 bits to be 0x8000, but we could probably relax this restriction to | 40 | * make sure that KERNEL_RAM_ADDR is correctly set. Currently, we expect |
42 | * TEXTADDR >= PAGE_OFFSET + 0x4000 | 41 | * the least significant 16 bits to be 0x8000, but we could probably |
43 | * | 42 | * relax this restriction to KERNEL_RAM_ADDR >= PAGE_OFFSET + 0x4000. |
44 | * Note that swapper_pg_dir is the virtual address of the page tables, and | ||
45 | * pgtbl gives us a position-independent reference to these tables. We can | ||
46 | * do this because stext == TEXTADDR | ||
47 | */ | 43 | */ |
48 | #if (TEXTADDR & 0xffff) != 0x8000 | 44 | #if (KERNEL_RAM_ADDR & 0xffff) != 0x8000 |
49 | #error TEXTADDR must start at 0xXXXX8000 | 45 | #error KERNEL_RAM_ADDR must start at 0xXXXX8000 |
50 | #endif | 46 | #endif |
51 | 47 | ||
52 | .globl swapper_pg_dir | 48 | .globl swapper_pg_dir |
53 | .equ swapper_pg_dir, TEXTADDR - 0x4000 | 49 | .equ swapper_pg_dir, KERNEL_RAM_ADDR - 0x4000 |
54 | 50 | ||
55 | .macro pgtbl, rd, phys | 51 | .macro pgtbl, rd |
56 | adr \rd, stext | 52 | ldr \rd, =(__virt_to_phys(KERNEL_RAM_ADDR - 0x4000)) |
57 | sub \rd, \rd, #0x4000 | ||
58 | .endm | 53 | .endm |
59 | #else | ||
60 | /* | ||
61 | * XIP Kernel: | ||
62 | * | ||
63 | * We place the page tables 16K below DATAADDR. Therefore, we must make sure | ||
64 | * that DATAADDR is correctly set. Currently, we expect the least significant | ||
65 | * 16 bits to be 0x8000, but we could probably relax this restriction to | ||
66 | * DATAADDR >= PAGE_OFFSET + 0x4000 | ||
67 | * | ||
68 | * Note that pgtbl is meant to return the physical address of swapper_pg_dir. | ||
69 | * We can't make it relative to the kernel position in this case since | ||
70 | * the kernel can physically be anywhere. | ||
71 | */ | ||
72 | #if (DATAADDR & 0xffff) != 0x8000 | ||
73 | #error DATAADDR must start at 0xXXXX8000 | ||
74 | #endif | ||
75 | |||
76 | .globl swapper_pg_dir | ||
77 | .equ swapper_pg_dir, DATAADDR - 0x4000 | ||
78 | 54 | ||
79 | .macro pgtbl, rd, phys | 55 | #ifdef CONFIG_XIP_KERNEL |
80 | ldr \rd, =((DATAADDR - 0x4000) - PAGE_OFFSET) | 56 | #define TEXTADDR XIP_VIRT_ADDR(CONFIG_XIP_PHYS_ADDR) |
81 | add \rd, \rd, \phys | 57 | #else |
82 | .endm | 58 | #define TEXTADDR KERNEL_RAM_ADDR |
83 | #endif | 59 | #endif |
84 | 60 | ||
85 | /* | 61 | /* |
@@ -280,7 +256,7 @@ __turn_mmu_on: | |||
280 | .type __create_page_tables, %function | 256 | .type __create_page_tables, %function |
281 | __create_page_tables: | 257 | __create_page_tables: |
282 | ldr r5, [r8, #MACHINFO_PHYSRAM] @ physram | 258 | ldr r5, [r8, #MACHINFO_PHYSRAM] @ physram |
283 | pgtbl r4, r5 @ page table address | 259 | pgtbl r4 @ page table address |
284 | 260 | ||
285 | /* | 261 | /* |
286 | * Clear the 16K level 1 swapper page table | 262 | * Clear the 16K level 1 swapper page table |