diff options
Diffstat (limited to 'arch/arm/kernel/head-common.S')
| -rw-r--r-- | arch/arm/kernel/head-common.S | 136 |
1 files changed, 39 insertions, 97 deletions
diff --git a/arch/arm/kernel/head-common.S b/arch/arm/kernel/head-common.S index bbecaac1e01..572a38335c9 100644 --- a/arch/arm/kernel/head-common.S +++ b/arch/arm/kernel/head-common.S @@ -15,6 +15,12 @@ #define ATAG_CORE_SIZE ((2*4 + 3*4) >> 2) #define ATAG_CORE_SIZE_EMPTY ((2*4) >> 2) +#ifdef CONFIG_CPU_BIG_ENDIAN +#define OF_DT_MAGIC 0xd00dfeed +#else +#define OF_DT_MAGIC 0xedfe0dd0 /* 0xd00dfeed in big-endian */ +#endif + /* * 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 @@ -25,100 +31,29 @@ * machine ID for example). */ __HEAD -__error_a: -#ifdef CONFIG_DEBUG_LL - mov r4, r1 @ preserve machine ID - adr r0, str_a1 - bl printascii - mov r0, r4 - bl printhex8 - adr r0, str_a2 - bl printascii - 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 - add r6, r6, r4 @ physical address space -1: ldr r0, [r5, #MACHINFO_TYPE] @ get machine type - bl printhex8 - mov r0, #'\t' - bl printch - ldr r0, [r5, #MACHINFO_NAME] @ get machine name - add r0, r0, r4 - bl printascii - mov r0, #'\n' - bl printch - add r5, r5, #SIZEOF_MACHINE_DESC @ next machine_desc - cmp r5, r6 - blo 1b - adr r0, str_a3 - bl printascii - b __error -ENDPROC(__error_a) - -str_a1: .asciz "\nError: unrecognized/unsupported machine ID (r1 = 0x" -str_a2: .asciz ").\n\nAvailable machine support:\n\nID (hex)\tNAME\n" -str_a3: .asciz "\nPlease check your kernel config and/or bootloader.\n" - .align -#endif - -/* - * Lookup machine architecture in the linker-build list of architectures. - * Note that we can't use the absolute addresses for the __arch_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. - * - * r1 = machine architecture number - * Returns: - * r3, r4, r6 corrupted - * r5 = mach_info pointer in physical address space - */ -__lookup_machine_type: - 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 - add r6, r6, r3 @ physical address space -1: ldr r3, [r5, #MACHINFO_TYPE] @ get machine type - teq r3, r1 @ matches loader number? - beq 2f @ found - add r5, r5, #SIZEOF_MACHINE_DESC @ next machine_desc - cmp r5, r6 - blo 1b - mov r5, #0 @ unknown machine -2: mov pc, lr -ENDPROC(__lookup_machine_type) - -/* - * Look in arch/arm/kernel/arch.[ch] for information about the - * __arch_info structures. - */ - .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 - * that the ATAG_CORE marker is first and present. Future revisions + * that the ATAG_CORE marker is first and present. If CONFIG_OF_FLATTREE + * is selected, then it will also accept a dtb pointer. Future revisions * of this function may be more lenient with the physical address and * may also be able to move the ATAGS block if necessary. * - * r8 = machinfo - * * Returns: - * r2 either valid atags pointer, or zero + * r2 either valid atags pointer, valid dtb pointer, or zero * r5, r6 corrupted */ __vet_atags: tst r2, #0x3 @ aligned? bne 1f - ldr r5, [r2, #0] @ is first tag ATAG_CORE? - cmp r5, #ATAG_CORE_SIZE + ldr r5, [r2, #0] +#ifdef CONFIG_OF_FLATTREE + ldr r6, =OF_DT_MAGIC @ is it a DTB? + cmp r5, r6 + beq 2f +#endif + cmp r5, #ATAG_CORE_SIZE @ is first tag ATAG_CORE? cmpne r5, #ATAG_CORE_SIZE_EMPTY bne 1f ldr r5, [r2, #4] @@ -126,7 +61,7 @@ __vet_atags: cmp r5, r6 bne 1f - mov pc, lr @ atag pointer is ok +2: mov pc, lr @ atag/dtb pointer is ok 1: mov r2, #0 mov pc, lr @@ -138,7 +73,7 @@ ENDPROC(__vet_atags) * * r0 = cp#15 control register * r1 = machine ID - * r2 = atags pointer + * r2 = atags/dtb pointer * r9 = processor ID */ __INIT @@ -163,8 +98,8 @@ __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 + strne r0, [r7] @ Save control register values b start_kernel ENDPROC(__mmap_switched) @@ -178,22 +113,15 @@ __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 /* - * 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) @@ -204,6 +132,9 @@ ENTRY(lookup_processor_type) ldmfd sp!, {r4 - r6, r9, pc} ENDPROC(lookup_processor_type) + __FINIT + .text + /* * 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 @@ -217,7 +148,6 @@ ENDPROC(lookup_processor_type) * 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} @@ -246,6 +176,18 @@ __lookup_processor_type_data: .long __proc_info_end .size __lookup_processor_type_data, . - __lookup_processor_type_data +__error_lpae: +#ifdef CONFIG_DEBUG_LL + adr r0, str_lpae + bl printascii + b __error +str_lpae: .asciz "\nError: Kernel with LPAE support, but CPU does not support LPAE.\n" +#else + b __error +#endif + .align +ENDPROC(__error_lpae) + __error_p: #ifdef CONFIG_DEBUG_LL adr r0, str_p1 |