[PATCH 1/6] ARM: fix be8 support for phys/virt address conversion
From: Junxiao Bi <hidden>
Date: 2011-12-08 10:07:47
Subsystem:
arm port, the rest · Maintainers:
Russell King, Linus Torvalds
phys_to_virt() and virt_to_phys() is implemented by one assembler instruction, add/sub an offset between the physical and virtual address. For some arm machines with CONFIG_ARM_PATCH_PHYS_VIRT defined, this offset is unknown at compile time, it is calculated dynamically at run time and then patched to the add/sub instruction. To support BE8 mode, firstly we need to convert the instruntion to big-endian after loading it from the memory, and then modify its offset field, at last convert it to little-endian and write it back to the memory. Reviewed-by: Nicolas Pitre <redacted> Signed-off-by: Junxiao Bi <redacted> --- arch/arm/kernel/head.S | 12 ++++++++++++ 1 files changed, 12 insertions(+), 0 deletions(-)
diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index 54fa641..a52aec7 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S@@ -565,8 +565,14 @@ __fixup_a_pv_table: b 2f 1: add r7, r3 ldrh ip, [r7, #2] +#ifdef CONFIG_CPU_ENDIAN_BE8 + rev16 ip, ip +#endif and ip, 0x8f00 orr ip, r6 @ mask in offset bits 31-24 +#ifdef CONFIG_CPU_ENDIAN_BE8 + rev16 ip, ip +#endif strh ip, [r7, #2] 2: cmp r4, r5 ldrcc r7, [r4], #4 @ use branch for delay slot
@@ -575,8 +581,14 @@ __fixup_a_pv_table: #else b 2f 1: ldr ip, [r7, r3] +#ifdef CONFIG_CPU_ENDIAN_BE8 + rev ip, ip +#endif bic ip, ip, #0x000000ff orr ip, ip, r6 @ mask in offset bits 31-24 +#ifdef CONFIG_CPU_ENDIAN_BE8 + rev ip, ip +#endif str ip, [r7, r3] 2: cmp r4, r5 ldrcc r7, [r4], #4 @ use branch for delay slot
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1.7.0.4