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-rw-r--r--arch/arm64/kernel/head.S52
1 files changed, 8 insertions, 44 deletions
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index 19f915e8f6e0..c0ff3ce4299e 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -237,8 +237,6 @@ ENTRY(stext)
bl el2_setup // Drop to EL1, w20=cpu_boot_mode
adrp x24, __PHYS_OFFSET
bl set_cpu_boot_mode_flag
-
- bl __vet_fdt
bl __create_page_tables // x25=TTBR0, x26=TTBR1
/*
* The following calls CPU setup code, see arch/arm64/mm/proc.S for
@@ -270,24 +268,6 @@ preserve_boot_args:
ENDPROC(preserve_boot_args)
/*
- * Determine validity of the x21 FDT pointer.
- * The dtb must be 8-byte aligned and live in the first 512M of memory.
- */
-__vet_fdt:
- tst x21, #0x7
- b.ne 1f
- cmp x21, x24
- b.lt 1f
- mov x0, #(1 << 29)
- add x0, x0, x24
- cmp x21, x0
- b.ge 1f
- ret
-1:
- mov x21, #0
- ret
-ENDPROC(__vet_fdt)
-/*
* Macro to create a table entry to the next page.
*
* tbl: page table address
@@ -348,8 +328,7 @@ ENDPROC(__vet_fdt)
* required to get the kernel running. The following sections are required:
* - identity mapping to enable the MMU (low address, TTBR0)
* - first few MB of the kernel linear mapping to jump to once the MMU has
- * been enabled, including the FDT blob (TTBR1)
- * - pgd entry for fixed mappings (TTBR1)
+ * been enabled
*/
__create_page_tables:
adrp x25, idmap_pg_dir
@@ -382,7 +361,7 @@ __create_page_tables:
* Create the identity mapping.
*/
mov x0, x25 // idmap_pg_dir
- adrp x3, KERNEL_START // __pa(KERNEL_START)
+ adrp x3, __idmap_text_start // __pa(__idmap_text_start)
#ifndef CONFIG_ARM64_VA_BITS_48
#define EXTRA_SHIFT (PGDIR_SHIFT + PAGE_SHIFT - 3)
@@ -405,11 +384,11 @@ __create_page_tables:
/*
* Calculate the maximum allowed value for TCR_EL1.T0SZ so that the
- * entire kernel image can be ID mapped. As T0SZ == (64 - #bits used),
+ * entire ID map region can be mapped. As T0SZ == (64 - #bits used),
* this number conveniently equals the number of leading zeroes in
- * the physical address of KERNEL_END.
+ * the physical address of __idmap_text_end.
*/
- adrp x5, KERNEL_END
+ adrp x5, __idmap_text_end
clz x5, x5
cmp x5, TCR_T0SZ(VA_BITS) // default T0SZ small enough?
b.ge 1f // .. then skip additional level
@@ -424,8 +403,8 @@ __create_page_tables:
#endif
create_pgd_entry x0, x3, x5, x6
- mov x5, x3 // __pa(KERNEL_START)
- adr_l x6, KERNEL_END // __pa(KERNEL_END)
+ mov x5, x3 // __pa(__idmap_text_start)
+ adr_l x6, __idmap_text_end // __pa(__idmap_text_end)
create_block_map x0, x7, x3, x5, x6
/*
@@ -439,22 +418,6 @@ __create_page_tables:
create_block_map x0, x7, x3, x5, x6
/*
- * Map the FDT blob (maximum 2MB; must be within 512MB of
- * PHYS_OFFSET).
- */
- mov x3, x21 // FDT phys address
- and x3, x3, #~((1 << 21) - 1) // 2MB aligned
- mov x6, #PAGE_OFFSET
- sub x5, x3, x24 // subtract PHYS_OFFSET
- tst x5, #~((1 << 29) - 1) // within 512MB?
- csel x21, xzr, x21, ne // zero the FDT pointer
- b.ne 1f
- add x5, x5, x6 // __va(FDT blob)
- add x6, x5, #1 << 21 // 2MB for the FDT blob
- sub x6, x6, #1 // inclusive range
- create_block_map x0, x7, x3, x5, x6
-1:
- /*
* Since the page tables have been populated with non-cacheable
* accesses (MMU disabled), invalidate the idmap and swapper page
* tables again to remove any speculatively loaded cache lines.
@@ -669,6 +632,7 @@ ENDPROC(__secondary_switched)
*
* other registers depend on the function called upon completion
*/
+ .section ".idmap.text", "ax"
__enable_mmu:
ldr x5, =vectors
msr vbar_el1, x5