From 26584853a44c58f3d6ac7360d697a2ddcd1a3efa Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Sat, 30 May 2009 14:00:18 +0100 Subject: Add core support for ARMv6/v7 big-endian Starting with ARMv6, the CPUs support the BE-8 variant of big-endian (byte-invariant). This patch adds the core support: - setting of the BE-8 mode via the CPSR.E register for both kernel and user threads - big-endian page table walking - REV used to rotate instructions read from memory during fault processing as they are still little-endian format - Kconfig and Makefile support for BE-8. The --be8 option must be passed to the final linking stage to convert the instructions to little-endian Signed-off-by: Catalin Marinas --- arch/arm/Makefile | 3 +++ arch/arm/boot/compressed/Makefile | 5 ++++- arch/arm/boot/compressed/head.S | 6 ++++++ arch/arm/include/asm/processor.h | 1 + arch/arm/include/asm/ptrace.h | 10 ++++++++++ arch/arm/kernel/entry-armv.S | 3 +++ arch/arm/kernel/entry-common.S | 3 +++ arch/arm/kernel/process.c | 2 +- arch/arm/mm/Kconfig | 14 ++++++++++++++ arch/arm/mm/abort-ev6.S | 3 +++ arch/arm/mm/proc-v6.S | 3 +++ arch/arm/mm/proc-v7.S | 3 +++ 12 files changed, 54 insertions(+), 2 deletions(-) diff --git a/arch/arm/Makefile b/arch/arm/Makefile index e84729bf13d..1167a4e8c7a 100644 --- a/arch/arm/Makefile +++ b/arch/arm/Makefile @@ -11,6 +11,9 @@ # Copyright (C) 1995-2001 by Russell King LDFLAGS_vmlinux :=-p --no-undefined -X +ifeq ($(CONFIG_CPU_ENDIAN_BE8),y) +LDFLAGS_vmlinux += --be8 +endif CPPFLAGS_vmlinux.lds = -DTEXT_OFFSET=$(TEXT_OFFSET) OBJCOPYFLAGS :=-O binary -R .note -R .note.gnu.build-id -R .comment -S GZFLAGS :=-9 diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile index fbe5eef1f6c..ce39dc54008 100644 --- a/arch/arm/boot/compressed/Makefile +++ b/arch/arm/boot/compressed/Makefile @@ -40,7 +40,7 @@ ifeq ($(CONFIG_PXA_SHARPSL),y) OBJS += head-sharpsl.o endif -ifeq ($(CONFIG_CPU_BIG_ENDIAN),y) +ifeq ($(CONFIG_CPU_ENDIAN_BE32),y) ifeq ($(CONFIG_CPU_CP15),y) OBJS += big-endian.o else @@ -78,6 +78,9 @@ EXTRA_AFLAGS := -Wa,-march=all # linker symbols. We only define initrd_phys and params_phys if the # machine class defined the corresponding makefile variable. LDFLAGS_vmlinux := --defsym zreladdr=$(ZRELADDR) +ifeq ($(CONFIG_CPU_ENDIAN_BE8),y) +LDFLAGS_vmlinux += --be8 +endif ifneq ($(INITRD_PHYS),) LDFLAGS_vmlinux += --defsym initrd_phys=$(INITRD_PHYS) endif diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S index b371fba1b95..01d49be3b2c 100644 --- a/arch/arm/boot/compressed/head.S +++ b/arch/arm/boot/compressed/head.S @@ -438,6 +438,9 @@ __armv4_mmu_cache_on: mrc p15, 0, r0, c1, c0, 0 @ read control reg orr r0, r0, #0x5000 @ I-cache enable, RR cache replacement orr r0, r0, #0x0030 +#ifdef CONFIG_CPU_ENDIAN_BE8 + orr r0, r0, #1 << 25 @ big-endian page tables +#endif bl __common_mmu_cache_on mov r0, #0 mcr p15, 0, r0, c8, c7, 0 @ flush I,D TLBs @@ -455,6 +458,9 @@ __armv7_mmu_cache_on: mrc p15, 0, r0, c1, c0, 0 @ read control reg orr r0, r0, #0x5000 @ I-cache enable, RR cache replacement orr r0, r0, #0x003c @ write buffer +#ifdef CONFIG_CPU_ENDIAN_BE8 + orr r0, r0, #1 << 25 @ big-endian page tables +#endif orrne r0, r0, #1 @ MMU enabled movne r1, #-1 mcrne p15, 0, r3, c2, c0, 0 @ load page table pointer diff --git a/arch/arm/include/asm/processor.h b/arch/arm/include/asm/processor.h index 1845892260e..6a89567ffc5 100644 --- a/arch/arm/include/asm/processor.h +++ b/arch/arm/include/asm/processor.h @@ -71,6 +71,7 @@ struct thread_struct { regs->ARM_cpsr = USR26_MODE; \ if (elf_hwcap & HWCAP_THUMB && pc & 1) \ regs->ARM_cpsr |= PSR_T_BIT; \ + regs->ARM_cpsr |= PSR_ENDSTATE; \ regs->ARM_pc = pc & ~1; /* pc */ \ regs->ARM_sp = sp; /* sp */ \ regs->ARM_r2 = stack[2]; /* r2 (envp) */ \ diff --git a/arch/arm/include/asm/ptrace.h b/arch/arm/include/asm/ptrace.h index 4a4290f7b4a..67b833c9b6b 100644 --- a/arch/arm/include/asm/ptrace.h +++ b/arch/arm/include/asm/ptrace.h @@ -50,6 +50,7 @@ #define PSR_F_BIT 0x00000040 #define PSR_I_BIT 0x00000080 #define PSR_A_BIT 0x00000100 +#define PSR_E_BIT 0x00000200 #define PSR_J_BIT 0x01000000 #define PSR_Q_BIT 0x08000000 #define PSR_V_BIT 0x10000000 @@ -72,6 +73,15 @@ #define PSR_IT_MASK 0x0600fc00 /* If-Then execution state mask */ #define PSR_ENDIAN_MASK 0x00000200 /* Endianness state mask */ +/* + * Default endianness state + */ +#ifdef CONFIG_CPU_ENDIAN_BE8 +#define PSR_ENDSTATE PSR_E_BIT +#else +#define PSR_ENDSTATE 0 +#endif + #ifndef __ASSEMBLY__ /* diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S index d662a2f1fd8..9d7ce4377c5 100644 --- a/arch/arm/kernel/entry-armv.S +++ b/arch/arm/kernel/entry-armv.S @@ -482,6 +482,9 @@ __und_usr: subeq r4, r2, #4 @ ARM instr at LR - 4 subne r4, r2, #2 @ Thumb instr at LR - 2 1: ldreqt r0, [r4] +#ifdef CONFIG_CPU_ENDIAN_BE8 + reveq r0, r0 @ little endian instruction +#endif beq call_fpe @ Thumb instruction #if __LINUX_ARM_ARCH__ >= 7 diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index b55cb033180..366e5097a41 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -210,6 +210,9 @@ ENTRY(vector_swi) A710( teq ip, #0x0f000000 ) A710( bne .Larm710bug ) #endif +#ifdef CONFIG_CPU_ENDIAN_BE8 + rev r10, r10 @ little endian instruction +#endif #elif defined(CONFIG_AEABI) diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index c3265a2e7cd..1585423699e 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -365,7 +365,7 @@ pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags) regs.ARM_r2 = (unsigned long)fn; regs.ARM_r3 = (unsigned long)do_exit; regs.ARM_pc = (unsigned long)kernel_thread_helper; - regs.ARM_cpsr = SVC_MODE; + regs.ARM_cpsr = SVC_MODE | PSR_ENDSTATE; return do_fork(flags|CLONE_VM|CLONE_UNTRACED, 0, ®s, 0, NULL, NULL); } diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig index 76bbcde049b..a25f34bd99d 100644 --- a/arch/arm/mm/Kconfig +++ b/arch/arm/mm/Kconfig @@ -639,6 +639,20 @@ config CPU_BIG_ENDIAN port must properly enable any big-endian related features of your chipset/board/processor. +config CPU_ENDIAN_BE8 + bool + depends on CPU_BIG_ENDIAN + default CPU_V6 || CPU_V7 + help + Support for the BE-8 (big-endian) mode on ARMv6 and ARMv7 processors. + +config CPU_ENDIAN_BE32 + bool + depends on CPU_BIG_ENDIAN + default !CPU_ENDIAN_BE8 + help + Support for the BE-32 (big-endian) mode on pre-ARMv6 processors. + config CPU_HIGH_VECTOR depends on !MMU && CPU_CP15 && !CPU_ARM740T bool "Select the High exception vector" diff --git a/arch/arm/mm/abort-ev6.S b/arch/arm/mm/abort-ev6.S index 6f7e70907e4..f332df7f0d3 100644 --- a/arch/arm/mm/abort-ev6.S +++ b/arch/arm/mm/abort-ev6.S @@ -37,6 +37,9 @@ ENTRY(v6_early_abort) movne pc, lr do_thumb_abort ldreq r3, [r2] @ read aborted ARM instruction +#ifdef CONFIG_CPU_ENDIAN_BE8 + reveq r3, r3 +#endif do_ldrd_abort tst r3, #1 << 20 @ L = 0 -> write orreq r1, r1, #1 << 11 @ yes. diff --git a/arch/arm/mm/proc-v6.S b/arch/arm/mm/proc-v6.S index 087e239704d..524ddae9259 100644 --- a/arch/arm/mm/proc-v6.S +++ b/arch/arm/mm/proc-v6.S @@ -170,6 +170,9 @@ __v6_setup: #endif /* CONFIG_MMU */ adr r5, v6_crval ldmia r5, {r5, r6} +#ifdef CONFIG_CPU_ENDIAN_BE8 + orr r6, r6, #1 << 25 @ big-endian page tables +#endif mrc p15, 0, r0, c1, c0, 0 @ read control register bic r0, r0, r5 @ clear bits them orr r0, r0, r6 @ set them diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S index 0a8ffd3c03f..4f8486475a7 100644 --- a/arch/arm/mm/proc-v7.S +++ b/arch/arm/mm/proc-v7.S @@ -253,6 +253,9 @@ __v7_setup: mcr p15, 0, r6, c10, c2, 1 @ write NMRR adr r5, v7_crval ldmia r5, {r5, r6} +#ifdef CONFIG_CPU_ENDIAN_BE8 + orr r6, r6, #1 << 25 @ big-endian page tables +#endif mrc p15, 0, r0, c1, c0, 0 @ read control register bic r0, r0, r5 @ clear bits them orr r0, r0, r6 @ set them -- cgit v1.2.3