path: root/arch/arm64/kernel/head.S
diff options
authorMark Salter <msalter@redhat.com>2014-04-07 15:39:52 -0700
committerMark Brown <broonie@linaro.org>2014-08-11 21:47:23 +0100
commit9a420417eed3930367f757f95c98a0769bf4bb0a (patch)
treed58612f1c8d012f7723bd62b367ee376e65d8523 /arch/arm64/kernel/head.S
parent4cd6ce8ecc81bd4fb7459fad8718cd66176ce793 (diff)
arm64: add early_ioremap support
Add support for early IO or memory mappings which are needed before the normal ioremap() is usable. This also adds fixmap support for permanent fixed mappings such as that used by the earlyprintk device register region. Signed-off-by: Mark Salter <msalter@redhat.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Borislav Petkov <borislav.petkov@amd.com> Cc: Dave Young <dyoung@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> (cherry picked from commit bf4b558eba920a38f91beb5ee62a8ce2628c92f7) Signed-off-by: Mark Brown <broonie@linaro.org> Conflicts: Documentation/arm64/memory.txt arch/arm64/Kconfig arch/arm64/kernel/head.S arch/arm64/mm/mmu.c
Diffstat (limited to 'arch/arm64/kernel/head.S')
1 files changed, 3 insertions, 6 deletions
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index 05a104c59510..5dd81278d8b0 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -403,7 +403,7 @@ ENDPROC(__calc_phys_offset)
* - 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)
- * - UART mapping if CONFIG_EARLY_PRINTK is enabled (TTBR1)
+ * - pgd entry for fixed mappings (TTBR1)
pgtbl x25, x26, x28 // idmap_pg_dir and swapper_pg_dir addresses
@@ -469,15 +469,12 @@ __create_page_tables:
sub x6, x6, #1 // inclusive range
create_block_map x0, x7, x3, x5, x6
- * Create the pgd entry for the UART mapping. The full mapping is done
- * later based earlyprintk kernel parameter.
+ * Create the pgd entry for the fixed mappings.
- ldr x5, =EARLYCON_IOBASE // UART virtual address
+ ldr x5, =FIXADDR_TOP // Fixed mapping virtual address
add x0, x26, #2 * PAGE_SIZE // section table address
create_pgd_entry x26, x0, x5, x6, x7
* Since the page tables have been populated with non-cacheable