diff options
| -rw-r--r-- | arch/arm/include/asm/cp15.h | 16 | ||||
| -rw-r--r-- | arch/arm/kernel/head-common.S | 9 | ||||
| -rw-r--r-- | arch/arm/mm/alignment.c | 2 | ||||
| -rw-r--r-- | arch/arm/mm/mmu.c | 17 |
4 files changed, 41 insertions, 3 deletions
diff --git a/arch/arm/include/asm/cp15.h b/arch/arm/include/asm/cp15.h index 5ef4d8015a60..1f3262e99d81 100644 --- a/arch/arm/include/asm/cp15.h +++ b/arch/arm/include/asm/cp15.h @@ -42,6 +42,8 @@ #define vectors_high() (0) #endif +#ifdef CONFIG_CPU_CP15 + extern unsigned long cr_no_alignment; /* defined in entry-armv.S */ extern unsigned long cr_alignment; /* defined in entry-armv.S */ @@ -82,6 +84,18 @@ static inline void set_copro_access(unsigned int val) isb(); } -#endif +#else /* ifdef CONFIG_CPU_CP15 */ + +/* + * cr_alignment and cr_no_alignment are tightly coupled to cp15 (at least in the + * minds of the developers). Yielding 0 for machines without a cp15 (and making + * it read-only) is fine for most cases and saves quite some #ifdeffery. + */ +#define cr_no_alignment UL(0) +#define cr_alignment UL(0) + +#endif /* ifdef CONFIG_CPU_CP15 / else */ + +#endif /* ifndef __ASSEMBLY__ */ #endif diff --git a/arch/arm/kernel/head-common.S b/arch/arm/kernel/head-common.S index 854bd22380d3..5b391a689b47 100644 --- a/arch/arm/kernel/head-common.S +++ b/arch/arm/kernel/head-common.S @@ -98,8 +98,9 @@ __mmap_switched: str r9, [r4] @ Save processor ID str r1, [r5] @ Save machine type str r2, [r6] @ Save atags pointer - bic r4, r0, #CR_A @ Clear 'A' bit - stmia r7, {r0, r4} @ Save control register values + cmp r7, #0 + bicne r4, r0, #CR_A @ Clear 'A' bit + stmneia r7, {r0, r4} @ Save control register values b start_kernel ENDPROC(__mmap_switched) @@ -113,7 +114,11 @@ __mmap_switched_data: .long processor_id @ r4 .long __machine_arch_type @ r5 .long __atags_pointer @ r6 +#ifdef CONFIG_CPU_CP15 .long cr_alignment @ r7 +#else + .long 0 @ r7 +#endif .long init_thread_union + THREAD_START_SP @ sp .size __mmap_switched_data, . - __mmap_switched_data diff --git a/arch/arm/mm/alignment.c b/arch/arm/mm/alignment.c index b820edaf3184..feeb3eaccb1c 100644 --- a/arch/arm/mm/alignment.c +++ b/arch/arm/mm/alignment.c @@ -964,12 +964,14 @@ static int __init alignment_init(void) return -ENOMEM; #endif +#ifdef CONFIG_CPU_CP15 if (cpu_is_v6_unaligned()) { cr_alignment &= ~CR_A; cr_no_alignment &= ~CR_A; set_cr(cr_alignment); ai_usermode = safe_usermode(ai_usermode, false); } +#endif hook_fault_code(FAULT_CODE_ALIGNMENT, do_alignment, SIGBUS, BUS_ADRALN, "alignment exception"); diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c index ce328c7f5c94..7c347bcc9421 100644 --- a/arch/arm/mm/mmu.c +++ b/arch/arm/mm/mmu.c @@ -97,6 +97,7 @@ static struct cachepolicy cache_policies[] __initdata = { } }; +#ifdef CONFIG_CPU_CP15 /* * These are useful for identifying cache coherency * problems by allowing the cache or the cache and @@ -195,6 +196,22 @@ void adjust_cr(unsigned long mask, unsigned long set) } #endif +#else /* ifdef CONFIG_CPU_CP15 */ + +static int __init early_cachepolicy(char *p) +{ + pr_warning("cachepolicy kernel parameter not supported without cp15\n"); +} +early_param("cachepolicy", early_cachepolicy); + +static int __init noalign_setup(char *__unused) +{ + pr_warning("noalign kernel parameter not supported without cp15\n"); +} +__setup("noalign", noalign_setup); + +#endif /* ifdef CONFIG_CPU_CP15 / else */ + #define PROT_PTE_DEVICE L_PTE_PRESENT|L_PTE_YOUNG|L_PTE_DIRTY|L_PTE_XN #define PROT_SECT_DEVICE PMD_TYPE_SECT|PMD_SECT_AP_WRITE |