From 139cc2ba7400dab80228a2bfa683e2f49cf5d3ff Mon Sep 17 00:00:00 2001 From: Victor Kamensky Date: Thu, 7 Nov 2013 08:42:41 +0100 Subject: ARM: 7882/1: mm: fix __phys_to_virt to work with 64 bit phys_addr_t in BE case Make sure that inline assembler that expects 'r' operand receives 32 bit value. Before this fix in case of CONFIG_ARCH_PHYS_ADDR_T_64BIT and CONFIG_ARM_PATCH_PHYS_VIRT __phys_to_virt function passed 64 bit value to __pv_stub inline assembler where 'r' operand is expected. Compiler behavior in such case is not well specified. It worked in little endian case, but in big endian case incorrect code was generated, where compiler confused which part of 64 bit value it needed to modify. For example BE snippet looked like this: N:0x80904E08 : MOV r2,#0 N:0x80904E0C : SUB r2,r2,#0x81000000 when LE similar code looked like this N:0x808FCE2C : MOV r2,r0 N:0x808FCE30 : SUB r2,r2,#0xc0, 8 ; #0xc0000000 Note 'r0' register is va that have to be translated into phys To avoid this situation use explicit cast to 'unsigned long', which explicitly discard upper part of phys address and convert value to 32 bit. Also add comment so such cast will not be removed in the future. Signed-off-by: Victor Kamensky Acked-by: Santosh Shilimkar Signed-off-by: Russell King --- arch/arm/include/asm/memory.h | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'arch/arm/include/asm/memory.h') diff --git a/arch/arm/include/asm/memory.h b/arch/arm/include/asm/memory.h index 4dd21457ef9d..9ecccc865046 100644 --- a/arch/arm/include/asm/memory.h +++ b/arch/arm/include/asm/memory.h @@ -226,7 +226,14 @@ static inline phys_addr_t __virt_to_phys(unsigned long x) static inline unsigned long __phys_to_virt(phys_addr_t x) { unsigned long t; - __pv_stub(x, t, "sub", __PV_BITS_31_24); + + /* + * 'unsigned long' cast discard upper word when + * phys_addr_t is 64 bit, and makes sure that inline + * assembler expression receives 32 bit argument + * in place where 'r' 32 bit operand is expected. + */ + __pv_stub((unsigned long) x, t, "sub", __PV_BITS_31_24); return t; } -- cgit v1.2.3 From b713aa0b15015a65ad5421543b80df86de043d62 Mon Sep 17 00:00:00 2001 From: Russell King Date: Tue, 10 Dec 2013 19:21:08 +0000 Subject: ARM: fix asm/memory.h build error Jason Gunthorpe reports a build failure when ARM_PATCH_PHYS_VIRT is not defined: In file included from arch/arm/include/asm/page.h:163:0, from include/linux/mm_types.h:16, from include/linux/sched.h:24, from arch/arm/kernel/asm-offsets.c:13: arch/arm/include/asm/memory.h: In function '__virt_to_phys': arch/arm/include/asm/memory.h:244:40: error: 'PHYS_OFFSET' undeclared (first use in this function) arch/arm/include/asm/memory.h:244:40: note: each undeclared identifier is reported only once for each function it appears in arch/arm/include/asm/memory.h: In function '__phys_to_virt': arch/arm/include/asm/memory.h:249:13: error: 'PHYS_OFFSET' undeclared (first use in this function) Fixes: ca5a45c06cd4 ("ARM: mm: use phys_addr_t appropriately in p2v and v2p conversions") Tested-By: Jason Gunthorpe Signed-off-by: Russell King --- arch/arm/include/asm/memory.h | 31 ++++++++++++++----------------- arch/arm/kernel/head-nommu.S | 4 ++-- arch/arm/kernel/head.S | 2 +- 3 files changed, 17 insertions(+), 20 deletions(-) (limited to 'arch/arm/include/asm/memory.h') diff --git a/arch/arm/include/asm/memory.h b/arch/arm/include/asm/memory.h index 9ecccc865046..6976b03e5213 100644 --- a/arch/arm/include/asm/memory.h +++ b/arch/arm/include/asm/memory.h @@ -100,23 +100,19 @@ #define TASK_UNMAPPED_BASE UL(0x00000000) #endif -#ifndef PHYS_OFFSET -#define PHYS_OFFSET UL(CONFIG_DRAM_BASE) -#endif - #ifndef END_MEM #define END_MEM (UL(CONFIG_DRAM_BASE) + CONFIG_DRAM_SIZE) #endif #ifndef PAGE_OFFSET -#define PAGE_OFFSET (PHYS_OFFSET) +#define PAGE_OFFSET PLAT_PHYS_OFFSET #endif /* * The module can be at any place in ram in nommu mode. */ #define MODULES_END (END_MEM) -#define MODULES_VADDR (PHYS_OFFSET) +#define MODULES_VADDR PAGE_OFFSET #define XIP_VIRT_ADDR(physaddr) (physaddr) @@ -157,6 +153,16 @@ #endif #define ARCH_PGD_MASK ((1 << ARCH_PGD_SHIFT) - 1) +/* + * PLAT_PHYS_OFFSET is the offset (from zero) of the start of physical + * memory. This is used for XIP and NoMMU kernels, or by kernels which + * have their own mach/memory.h. Assembly code must always use + * PLAT_PHYS_OFFSET and not PHYS_OFFSET. + */ +#ifndef PLAT_PHYS_OFFSET +#define PLAT_PHYS_OFFSET UL(CONFIG_PHYS_OFFSET) +#endif + #ifndef __ASSEMBLY__ /* @@ -239,6 +245,8 @@ static inline unsigned long __phys_to_virt(phys_addr_t x) #else +#define PHYS_OFFSET PLAT_PHYS_OFFSET + static inline phys_addr_t __virt_to_phys(unsigned long x) { return (phys_addr_t)x - PAGE_OFFSET + PHYS_OFFSET; @@ -251,17 +259,6 @@ static inline unsigned long __phys_to_virt(phys_addr_t x) #endif #endif -#endif /* __ASSEMBLY__ */ - -#ifndef PHYS_OFFSET -#ifdef PLAT_PHYS_OFFSET -#define PHYS_OFFSET PLAT_PHYS_OFFSET -#else -#define PHYS_OFFSET UL(CONFIG_PHYS_OFFSET) -#endif -#endif - -#ifndef __ASSEMBLY__ /* * PFNs are used to describe any physical page; this means diff --git a/arch/arm/kernel/head-nommu.S b/arch/arm/kernel/head-nommu.S index 14235ba64a90..716249cc2ee1 100644 --- a/arch/arm/kernel/head-nommu.S +++ b/arch/arm/kernel/head-nommu.S @@ -68,7 +68,7 @@ ENTRY(stext) #ifdef CONFIG_ARM_MPU /* Calculate the size of a region covering just the kernel */ - ldr r5, =PHYS_OFFSET @ Region start: PHYS_OFFSET + ldr r5, =PLAT_PHYS_OFFSET @ Region start: PHYS_OFFSET ldr r6, =(_end) @ Cover whole kernel sub r6, r6, r5 @ Minimum size of region to map clz r6, r6 @ Region size must be 2^N... @@ -213,7 +213,7 @@ ENTRY(__setup_mpu) set_region_nr r0, #MPU_RAM_REGION isb /* Full access from PL0, PL1, shared for CONFIG_SMP, cacheable */ - ldr r0, =PHYS_OFFSET @ RAM starts at PHYS_OFFSET + ldr r0, =PLAT_PHYS_OFFSET @ RAM starts at PHYS_OFFSET ldr r5,=(MPU_AP_PL1RW_PL0RW | MPU_RGN_NORMAL) setup_region r0, r5, r6, MPU_DATA_SIDE @ PHYS_OFFSET, shared, enabled diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S index 11d59b32fb8d..32f317e5828a 100644 --- a/arch/arm/kernel/head.S +++ b/arch/arm/kernel/head.S @@ -110,7 +110,7 @@ ENTRY(stext) sub r4, r3, r4 @ (PHYS_OFFSET - PAGE_OFFSET) add r8, r8, r4 @ PHYS_OFFSET #else - ldr r8, =PHYS_OFFSET @ always constant in this case + ldr r8, =PLAT_PHYS_OFFSET @ always constant in this case #endif /* -- cgit v1.2.3