diff options
Diffstat (limited to 'arch/arm/kernel/head-common.S')
| -rw-r--r-- | arch/arm/kernel/head-common.S | 305 |
1 files changed, 159 insertions, 146 deletions
diff --git a/arch/arm/kernel/head-common.S b/arch/arm/kernel/head-common.S index b9505aa267c..bbecaac1e01 100644 --- a/arch/arm/kernel/head-common.S +++ b/arch/arm/kernel/head-common.S @@ -15,55 +15,6 @@ #define ATAG_CORE_SIZE ((2*4 + 3*4) >> 2) #define ATAG_CORE_SIZE_EMPTY ((2*4) >> 2) - .align 2 - .type __switch_data, %object -__switch_data: - .long __mmap_switched - .long __data_loc @ r4 - .long _data @ r5 - .long __bss_start @ r6 - .long _end @ r7 - .long processor_id @ r4 - .long __machine_arch_type @ r5 - .long __atags_pointer @ r6 - .long cr_alignment @ r7 - .long init_thread_union + THREAD_START_SP @ sp - -/* - * The following fragment of code is executed with the MMU on in MMU mode, - * and uses absolute addresses; this is not position independent. - * - * r0 = cp#15 control register - * r1 = machine ID - * r2 = atags pointer - * r9 = processor ID - */ -__mmap_switched: - adr r3, __switch_data + 4 - - ldmia r3!, {r4, r5, r6, r7} - cmp r4, r5 @ Copy data segment if needed -1: cmpne r5, r6 - ldrne fp, [r4], #4 - strne fp, [r5], #4 - bne 1b - - mov fp, #0 @ Clear BSS (and zero fp) -1: cmp r6, r7 - strcc fp, [r6],#4 - bcc 1b - - ARM( ldmia r3, {r4, r5, r6, r7, sp}) - THUMB( ldmia r3, {r4, r5, r6, r7} ) - THUMB( ldr sp, [r3, #16] ) - 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 - b start_kernel -ENDPROC(__mmap_switched) - /* * Exception handling. Something went wrong and we can't proceed. We * ought to tell the user, but since we don't have any guarantee that @@ -73,21 +24,7 @@ ENDPROC(__mmap_switched) * and hope for the best (useful if bootloader fails to pass a proper * machine ID for example). */ -__error_p: -#ifdef CONFIG_DEBUG_LL - adr r0, str_p1 - bl printascii - mov r0, r9 - bl printhex8 - adr r0, str_p2 - bl printascii - b __error -str_p1: .asciz "\nError: unrecognized/unsupported processor variant (0x" -str_p2: .asciz ").\n" - .align -#endif -ENDPROC(__error_p) - + __HEAD __error_a: #ifdef CONFIG_DEBUG_LL mov r4, r1 @ preserve machine ID @@ -97,7 +34,7 @@ __error_a: bl printhex8 adr r0, str_a2 bl printascii - adr r3, 4f + adr r3, __lookup_machine_type_data ldmia r3, {r4, r5, r6} @ get machine desc list sub r4, r3, r4 @ get offset between virt&phys add r5, r5, r4 @ convert virt addresses to @@ -125,78 +62,6 @@ str_a3: .asciz "\nPlease check your kernel config and/or bootloader.\n" .align #endif -__error: -#ifdef CONFIG_ARCH_RPC -/* - * Turn the screen red on a error - RiscPC only. - */ - mov r0, #0x02000000 - mov r3, #0x11 - orr r3, r3, r3, lsl #8 - orr r3, r3, r3, lsl #16 - str r3, [r0], #4 - str r3, [r0], #4 - str r3, [r0], #4 - str r3, [r0], #4 -#endif -1: mov r0, r0 - b 1b -ENDPROC(__error) - - -/* - * Read processor ID register (CP#15, CR0), and look up in the linker-built - * supported processor list. Note that we can't use the absolute addresses - * for the __proc_info lists since we aren't running with the MMU on - * (and therefore, we are not in the correct address space). We have to - * calculate the offset. - * - * r9 = cpuid - * Returns: - * r3, r4, r6 corrupted - * r5 = proc_info pointer in physical address space - * r9 = cpuid (preserved) - */ -__lookup_processor_type: - adr r3, 3f - ldmia r3, {r5 - r7} - add r3, r3, #8 - sub r3, r3, r7 @ get offset between virt&phys - add r5, r5, r3 @ convert virt addresses to - add r6, r6, r3 @ physical address space -1: ldmia r5, {r3, r4} @ value, mask - and r4, r4, r9 @ mask wanted bits - teq r3, r4 - beq 2f - add r5, r5, #PROC_INFO_SZ @ sizeof(proc_info_list) - cmp r5, r6 - blo 1b - mov r5, #0 @ unknown processor -2: mov pc, lr -ENDPROC(__lookup_processor_type) - -/* - * This provides a C-API version of the above function. - */ -ENTRY(lookup_processor_type) - stmfd sp!, {r4 - r7, r9, lr} - mov r9, r0 - bl __lookup_processor_type - mov r0, r5 - ldmfd sp!, {r4 - r7, r9, pc} -ENDPROC(lookup_processor_type) - -/* - * Look in <asm/procinfo.h> and arch/arm/kernel/arch.[ch] for - * more information about the __proc_info and __arch_info structures. - */ - .align 2 -3: .long __proc_info_begin - .long __proc_info_end -4: .long . - .long __arch_info_begin - .long __arch_info_end - /* * Lookup machine architecture in the linker-build list of architectures. * Note that we can't use the absolute addresses for the __arch_info @@ -209,7 +74,7 @@ ENDPROC(lookup_processor_type) * r5 = mach_info pointer in physical address space */ __lookup_machine_type: - adr r3, 4b + adr r3, __lookup_machine_type_data ldmia r3, {r4, r5, r6} sub r3, r3, r4 @ get offset between virt&phys add r5, r5, r3 @ convert virt addresses to @@ -225,15 +90,16 @@ __lookup_machine_type: ENDPROC(__lookup_machine_type) /* - * This provides a C-API version of the above function. + * Look in arch/arm/kernel/arch.[ch] for information about the + * __arch_info structures. */ -ENTRY(lookup_machine_type) - stmfd sp!, {r4 - r6, lr} - mov r1, r0 - bl __lookup_machine_type - mov r0, r5 - ldmfd sp!, {r4 - r6, pc} -ENDPROC(lookup_machine_type) + .align 2 + .type __lookup_machine_type_data, %object +__lookup_machine_type_data: + .long . + .long __arch_info_begin + .long __arch_info_end + .size __lookup_machine_type_data, . - __lookup_machine_type_data /* Determine validity of the r2 atags pointer. The heuristic requires * that the pointer be aligned, in the first 16k of physical RAM and @@ -265,3 +131,150 @@ __vet_atags: 1: mov r2, #0 mov pc, lr ENDPROC(__vet_atags) + +/* + * The following fragment of code is executed with the MMU on in MMU mode, + * and uses absolute addresses; this is not position independent. + * + * r0 = cp#15 control register + * r1 = machine ID + * r2 = atags pointer + * r9 = processor ID + */ + __INIT +__mmap_switched: + adr r3, __mmap_switched_data + + ldmia r3!, {r4, r5, r6, r7} + cmp r4, r5 @ Copy data segment if needed +1: cmpne r5, r6 + ldrne fp, [r4], #4 + strne fp, [r5], #4 + bne 1b + + mov fp, #0 @ Clear BSS (and zero fp) +1: cmp r6, r7 + strcc fp, [r6],#4 + bcc 1b + + ARM( ldmia r3, {r4, r5, r6, r7, sp}) + THUMB( ldmia r3, {r4, r5, r6, r7} ) + THUMB( ldr sp, [r3, #16] ) + 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 + b start_kernel +ENDPROC(__mmap_switched) + + .align 2 + .type __mmap_switched_data, %object +__mmap_switched_data: + .long __data_loc @ r4 + .long _sdata @ r5 + .long __bss_start @ r6 + .long _end @ r7 + .long processor_id @ r4 + .long __machine_arch_type @ r5 + .long __atags_pointer @ r6 + .long cr_alignment @ r7 + .long init_thread_union + THREAD_START_SP @ sp + .size __mmap_switched_data, . - __mmap_switched_data + +/* + * This provides a C-API version of __lookup_machine_type + */ +ENTRY(lookup_machine_type) + stmfd sp!, {r4 - r6, lr} + mov r1, r0 + bl __lookup_machine_type + mov r0, r5 + ldmfd sp!, {r4 - r6, pc} +ENDPROC(lookup_machine_type) + +/* + * This provides a C-API version of __lookup_processor_type + */ +ENTRY(lookup_processor_type) + stmfd sp!, {r4 - r6, r9, lr} + mov r9, r0 + bl __lookup_processor_type + mov r0, r5 + ldmfd sp!, {r4 - r6, r9, pc} +ENDPROC(lookup_processor_type) + +/* + * Read processor ID register (CP#15, CR0), and look up in the linker-built + * supported processor list. Note that we can't use the absolute addresses + * for the __proc_info lists since we aren't running with the MMU on + * (and therefore, we are not in the correct address space). We have to + * calculate the offset. + * + * r9 = cpuid + * Returns: + * r3, r4, r6 corrupted + * r5 = proc_info pointer in physical address space + * r9 = cpuid (preserved) + */ + __CPUINIT +__lookup_processor_type: + adr r3, __lookup_processor_type_data + ldmia r3, {r4 - r6} + sub r3, r3, r4 @ get offset between virt&phys + add r5, r5, r3 @ convert virt addresses to + add r6, r6, r3 @ physical address space +1: ldmia r5, {r3, r4} @ value, mask + and r4, r4, r9 @ mask wanted bits + teq r3, r4 + beq 2f + add r5, r5, #PROC_INFO_SZ @ sizeof(proc_info_list) + cmp r5, r6 + blo 1b + mov r5, #0 @ unknown processor +2: mov pc, lr +ENDPROC(__lookup_processor_type) + +/* + * Look in <asm/procinfo.h> for information about the __proc_info structure. + */ + .align 2 + .type __lookup_processor_type_data, %object +__lookup_processor_type_data: + .long . + .long __proc_info_begin + .long __proc_info_end + .size __lookup_processor_type_data, . - __lookup_processor_type_data + +__error_p: +#ifdef CONFIG_DEBUG_LL + adr r0, str_p1 + bl printascii + mov r0, r9 + bl printhex8 + adr r0, str_p2 + bl printascii + b __error +str_p1: .asciz "\nError: unrecognized/unsupported processor variant (0x" +str_p2: .asciz ").\n" + .align +#endif +ENDPROC(__error_p) + +__error: +#ifdef CONFIG_ARCH_RPC +/* + * Turn the screen red on a error - RiscPC only. + */ + mov r0, #0x02000000 + mov r3, #0x11 + orr r3, r3, r3, lsl #8 + orr r3, r3, r3, lsl #16 + str r3, [r0], #4 + str r3, [r0], #4 + str r3, [r0], #4 + str r3, [r0], #4 +#endif +1: mov r0, r0 + b 1b +ENDPROC(__error) |