diff options
Diffstat (limited to 'arch/m32r/kernel/head.S')
| -rw-r--r-- | arch/m32r/kernel/head.S | 287 |
1 files changed, 287 insertions, 0 deletions
diff --git a/arch/m32r/kernel/head.S b/arch/m32r/kernel/head.S new file mode 100644 index 00000000000..3e83173995c --- /dev/null +++ b/arch/m32r/kernel/head.S @@ -0,0 +1,287 @@ +/* + * linux/arch/m32r/kernel/head.S + * + * M32R startup code. + * + * Copyright (c) 2001, 2002 Hiroyuki Kondo, Hirokazu Takata, + * Hitoshi Yamamoto + */ + +/* $Id$ */ + +#include <linux/init.h> +__INIT +__INITDATA + + .text +#include <linux/config.h> +#include <linux/linkage.h> +#include <asm/segment.h> +#include <asm/page.h> +#include <asm/pgtable.h> +#include <asm/assembler.h> +#include <asm/m32r.h> +#include <asm/mmu_context.h> + +/* + * References to members of the boot_cpu_data structure. + */ + .text + .global start_kernel + .global __bss_start + .global _end +ENTRY(stext) +ENTRY(_stext) +ENTRY(startup_32) + /* Setup up the stack pointer */ + LDIMM (r0, spi_stack_top) + LDIMM (r1, spu_stack_top) + mvtc r0, spi + mvtc r1, spu + + /* Initilalize PSW */ + ldi r0, #0x0000 /* use SPI, disable EI */ + mvtc r0, psw + + /* Set up the stack pointer */ + LDIMM (r0, stack_start) + ld r0, @r0 + mvtc r0, spi + +/* + * Clear BSS first so that there are no surprises... + */ +#ifdef CONFIG_ISA_DUAL_ISSUE + + LDIMM (r2, __bss_start) + LDIMM (r3, _end) + sub r3, r2 ; BSS size in bytes + ; R4 = BSS size in longwords (rounded down) + mv r4, r3 || ldi r1, #0 + srli r4, #4 || addi r2, #-4 + beqz r4, .Lendloop1 +.Lloop1: +#ifndef CONFIG_CHIP_M32310 + ; Touch memory for the no-write-allocating cache. + ld r0, @(4,r2) +#endif + st r1, @+r2 || addi r4, #-1 + st r1, @+r2 + st r1, @+r2 + st r1, @+r2 || cmpeq r1, r4 ; R4 = 0? + bnc .Lloop1 +.Lendloop1: + and3 r4, r3, #15 + addi r2, #4 + beqz r4, .Lendloop2 +.Lloop2: + stb r1, @r2 || addi r4, #-1 + addi r2, #1 + bnez r4, .Lloop2 +.Lendloop2: + +#else /* not CONFIG_ISA_DUAL_ISSUE */ + + LDIMM (r2, __bss_start) + LDIMM (r3, _end) + sub r3, r2 ; BSS size in bytes + mv r4, r3 + srli r4, #2 ; R4 = BSS size in longwords (rounded down) + ldi r1, #0 ; clear R1 for longwords store + addi r2, #-4 ; account for pre-inc store + beqz r4, .Lendloop1 ; any more to go? +.Lloop1: + st r1, @+r2 ; yep, zero out another longword + addi r4, #-1 ; decrement count + bnez r4, .Lloop1 ; go do some more +.Lendloop1: + and3 r4, r3, #3 ; get no. of remaining BSS bytes to clear + addi r2, #4 ; account for pre-inc store + beqz r4, .Lendloop2 ; any more to go? +.Lloop2: + stb r1, @r2 ; yep, zero out another byte + addi r2, #1 ; bump address + addi r4, #-1 ; decrement count + bnez r4, .Lloop2 ; go do some more +.Lendloop2: + +#endif /* not CONFIG_ISA_DUAL_ISSUE */ + +#if 0 /* M32R_FIXME */ +/* + * Copy data segment from ROM to RAM. + */ + .global ROM_D, TOP_DATA, END_DATA + + LDIMM (r1, ROM_D) + LDIMM (r2, TOP_DATA) + LDIMM (r3, END_DATA) + addi r2, #-4 + addi r3, #-4 +loop1: + ld r0, @r1+ + st r0, @+r2 + cmp r2, r3 + bc loop1 +#endif /* 0 */ + +/* Jump to kernel */ + LDIMM (r2, start_kernel) + jl r2 + .fillinsn +1: + bra 1b ; main should never return here, but + ; just in case, we know what happens. + +#ifdef CONFIG_SMP +/* + * AP startup routine + */ + .text + .global eit_vector +ENTRY(startup_AP) +;; setup EVB + LDIMM (r4, eit_vector) + mvtc r4, cr5 + +;; enable MMU + LDIMM (r2, init_tlb) + jl r2 + seth r4, #high(MATM) + or3 r4, r4, #low(MATM) + ldi r5, #0x01 + st r5, @r4 ; Set MATM Reg(T bit ON) + ld r6, @r4 ; MATM Check + LDIMM (r5, 1f) + jmp r5 ; enable MMU + nop + .fillinsn +1: +;; ISN check + ld r6, @r4 ; MATM Check + seth r4, #high(M32R_ICU_ISTS_ADDR) + or3 r4, r4, #low(M32R_ICU_ISTS_ADDR) + ld r5, @r4 ; Read ISTSi reg. + mv r6, r5 + slli r5, #13 ; PIML check + srli r5, #13 ; + seth r4, #high(M32R_ICU_IMASK_ADDR) + or3 r4, r4, #low(M32R_ICU_IMASK_ADDR) + st r5, @r4 ; Write IMASKi reg. + slli r6, #4 ; ISN check + srli r6, #26 ; + seth r4, #high(M32R_IRQ_IPI5) + or3 r4, r4, #low(M32R_IRQ_IPI5) + bne r4, r6, 2f ; if (ISN != CPU_BOOT_IPI) goto sleep; + +;; check cpu_bootout_map and set cpu_bootin_map + LDIMM (r4, cpu_bootout_map) + ld r4, @r4 + seth r5, #high(M32R_CPUID_PORTL) + or3 r5, r5, #low(M32R_CPUID_PORTL) + ld r5, @r5 + ldi r6, #1 + sll r6, r5 + and r4, r6 + beqz r4, 2f + LDIMM (r4, cpu_bootin_map) + ld r5, @r4 + or r5, r6 + st r6, @r4 + +;; clear PSW + ldi r4, #0 + mvtc r4, psw + +;; setup SPI + LDIMM (r4, stack_start) + ld r4, @r4 + mvtc r4, spi + +;; setup BPC (start_secondary) + LDIMM (r4, start_secondary) + mvtc r4, bpc + + rte ; goto startup_secondary + nop + nop + + .fillinsn +2: + ;; disable MMU + seth r4, #high(MATM) + or3 r4, r4, #low(MATM) + ldi r5, #0 + st r5, @r4 ; Set MATM Reg(T bit OFF) + ld r6, @r4 ; MATM Check + LDIMM (r4, 3f) + seth r5, #high(__PAGE_OFFSET) + or3 r5, r5, #low(__PAGE_OFFSET) + not r5, r5 + and r4, r5 + jmp r4 ; disable MMU + nop + .fillinsn +3: + ;; SLEEP and wait IPI + LDIMM (r4, AP_loop) + seth r5, #high(__PAGE_OFFSET) + or3 r5, r5, #low(__PAGE_OFFSET) + not r5, r5 + and r4, r5 + jmp r4 + nop + nop +#endif /* CONFIG_SMP */ + +ENTRY(stack_start) + .long init_thread_union+8192 + .long __KERNEL_DS + +/* + * This is initialized to create a identity-mapping at 0-4M (for bootup + * purposes) and another mapping of the 0-4M area at virtual address + * PAGE_OFFSET. + */ + .text + +#define MOUNT_ROOT_RDONLY 1 +#define RAMDISK_FLAGS 0 ; 1024KB +#define ORIG_ROOT_DEV 0x0100 ; /dev/ram0 (major:01, minor:00) +#define LOADER_TYPE 1 ; (??? - non-zero value seems + ; to be needed to boot from initrd) + +#define COMMAND_LINE "" + + .section .empty_zero_page, "aw" +ENTRY(empty_zero_page) + .long MOUNT_ROOT_RDONLY /* offset: +0x00 */ + .long RAMDISK_FLAGS + .long ORIG_ROOT_DEV + .long LOADER_TYPE + .long 0 /* INITRD_START */ /* +0x10 */ + .long 0 /* INITRD_SIZE */ + .long 0 /* CPU_CLOCK */ + .long 0 /* BUS_CLOCK */ + .long 0 /* TIMER_DIVIDE */ /* +0x20 */ + .balign 256,0 + .asciz COMMAND_LINE + .byte 0 + .balign 4096,0,4096 + +/*------------------------------------------------------------------------ + * Stack area + */ + .section .spi + ALIGN + .global spi_stack_top + .zero 1024 +spi_stack_top: + + .section .spu + ALIGN + .global spu_stack_top + .zero 1024 +spu_stack_top: + + .end |