X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Farm%2Fkernel%2Fhead.S;h=cf495a3084b31f8a7ead7089508ff16096864ae9;hb=97bf2856c6014879bd04983a3e9dfcdac1e7fe85;hp=587ac675640b311faf5f928ed1ae30c739bd08bf;hpb=6a77f38946aaee1cd85eeec6cf4229b204c15071;p=linux-2.6.git diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S index 587ac6756..cf495a308 100644 --- a/arch/arm/kernel/head.S +++ b/arch/arm/kernel/head.S @@ -2,6 +2,8 @@ * linux/arch/arm/kernel/head.S * * Copyright (C) 1994-2002 Russell King + * Copyright (c) 2003 ARM Limited + * All Rights Reserved * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as @@ -9,71 +11,46 @@ * * Kernel startup code for all 32-bit CPUs */ -#include #include #include #include #include -#include -#include #include -#include +#include +#include +#include #include -#define PROCINFO_MMUFLAGS 8 -#define PROCINFO_INITFUNC 12 - -#define MACHINFO_PHYSRAM 4 -#define MACHINFO_PHYSIO 8 -#define MACHINFO_PGOFFIO 12 - -#ifndef CONFIG_XIP_KERNEL -/* - * We place the page tables 16K below TEXTADDR. Therefore, we must make sure - * that TEXTADDR is correctly set. Currently, we expect the least significant - * 16 bits to be 0x8000, but we could probably relax this restriction to - * TEXTADDR >= PAGE_OFFSET + 0x4000 - * - * Note that swapper_pg_dir is the virtual address of the page tables, and - * pgtbl gives us a position-independent reference to these tables. We can - * do this because stext == TEXTADDR - */ -#if (TEXTADDR & 0xffff) != 0x8000 -#error TEXTADDR must start at 0xXXXX8000 +#if (PHYS_OFFSET & 0x001fffff) +#error "PHYS_OFFSET must be at an even 2MiB boundary!" #endif - .globl swapper_pg_dir - .equ swapper_pg_dir, TEXTADDR - 0x4000 +#define KERNEL_RAM_VADDR (PAGE_OFFSET + TEXT_OFFSET) +#define KERNEL_RAM_PADDR (PHYS_OFFSET + TEXT_OFFSET) - .macro pgtbl, rd, phys - adr \rd, stext - sub \rd, \rd, #0x4000 - .endm -#else /* - * XIP Kernel: - * - * We place the page tables 16K below DATAADDR. Therefore, we must make sure - * that DATAADDR is correctly set. Currently, we expect the least significant - * 16 bits to be 0x8000, but we could probably relax this restriction to - * DATAADDR >= PAGE_OFFSET + 0x4000 - * - * Note that pgtbl is meant to return the physical address of swapper_pg_dir. - * We can't make it relative to the kernel position in this case since - * the kernel can physically be anywhere. + * swapper_pg_dir is the virtual address of the initial page table. + * We place the page tables 16K below KERNEL_RAM_VADDR. Therefore, we must + * make sure that KERNEL_RAM_VADDR is correctly set. Currently, we expect + * the least significant 16 bits to be 0x8000, but we could probably + * relax this restriction to KERNEL_RAM_VADDR >= PAGE_OFFSET + 0x4000. */ -#if (DATAADDR & 0xffff) != 0x8000 -#error DATAADDR must start at 0xXXXX8000 +#if (KERNEL_RAM_VADDR & 0xffff) != 0x8000 +#error KERNEL_RAM_VADDR must start at 0xXXXX8000 #endif .globl swapper_pg_dir - .equ swapper_pg_dir, DATAADDR - 0x4000 + .equ swapper_pg_dir, KERNEL_RAM_VADDR - 0x4000 - .macro pgtbl, rd, phys - ldr \rd, =((DATAADDR - 0x4000) - VIRT_OFFSET) - add \rd, \rd, \phys + .macro pgtbl, rd + ldr \rd, =(KERNEL_RAM_PADDR - 0x4000) .endm + +#ifdef CONFIG_XIP_KERNEL +#define TEXTADDR XIP_VIRT_ADDR(CONFIG_XIP_PHYS_ADDR) +#else +#define TEXTADDR KERNEL_RAM_VADDR #endif /* @@ -97,16 +74,15 @@ __INIT .type stext, %function ENTRY(stext) - msr cpsr_c, #PSR_F_BIT | PSR_I_BIT | MODE_SVC @ ensure svc mode + msr cpsr_c, #PSR_F_BIT | PSR_I_BIT | SVC_MODE @ ensure svc mode @ and irqs disabled + mrc p15, 0, r9, c0, c0 @ get processor id bl __lookup_processor_type @ r5=procinfo r9=cpuid movs r10, r5 @ invalid processor (r5=0)? - moveq r0, #'p' @ yes, error 'p' - beq __error + beq __error_p @ yes, error 'p' bl __lookup_machine_type @ r5=machinfo movs r8, r5 @ invalid machine (r5=0)? - moveq r0, #'a' @ yes, error 'a' - beq __error + beq __error_a @ yes, error 'a' bl __create_page_tables /* @@ -121,48 +97,48 @@ ENTRY(stext) adr lr, __enable_mmu @ return (PIC) address add pc, r10, #PROCINFO_INITFUNC - .type __switch_data, %object -__switch_data: - .long __mmap_switched - .long __data_loc @ r4 - .long __data_start @ r5 - .long __bss_start @ r6 - .long _end @ r7 - .long processor_id @ r4 - .long __machine_arch_type @ r5 - .long cr_alignment @ r6 - .long init_thread_union+8192 @ sp - -/* - * The following fragment of code is executed with the MMU on, and uses - * absolute addresses; this is not position independent. - * - * r0 = cp#15 control register - * r1 = machine ID - * r9 = processor ID - */ - .type __mmap_switched, %function -__mmap_switched: - adr r3, __switch_data + 4 +#if defined(CONFIG_SMP) + .type secondary_startup, #function +ENTRY(secondary_startup) + /* + * Common entry point for secondary CPUs. + * + * Ensure that we're in SVC mode, and IRQs are disabled. Lookup + * the processor type - there is no need to check the machine type + * as it has already been validated by the primary processor. + */ + msr cpsr_c, #PSR_F_BIT | PSR_I_BIT | SVC_MODE + mrc p15, 0, r9, c0, c0 @ get processor id + bl __lookup_processor_type + movs r10, r5 @ invalid processor? + moveq r0, #'p' @ yes, error 'p' + beq __error - 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 + /* + * Use the page tables supplied from __cpu_up. + */ + adr r4, __secondary_data + ldmia r4, {r5, r7, r13} @ address to jump to after + sub r4, r4, r5 @ mmu has been enabled + ldr r4, [r7, r4] @ get secondary_data.pgdir + adr lr, __enable_mmu @ return address + add pc, r10, #PROCINFO_INITFUNC @ initialise processor + @ (return control reg) - mov fp, #0 @ Clear BSS (and zero fp) -1: cmp r6, r7 - strcc fp, [r6],#4 - bcc 1b + /* + * r6 = &secondary_data + */ +ENTRY(__secondary_switched) + ldr sp, [r7, #4] @ get secondary_data.stack + mov fp, #0 + b secondary_start_kernel - ldmia r3, {r4, r5, r6, sp} - str r9, [r4] @ Save processor ID - str r1, [r5] @ Save machine type - bic r4, r0, #CR_A @ Clear 'A' bit - stmia r6, {r0, r4} @ Save control register values - b start_kernel + .type __secondary_data, %object +__secondary_data: + .long . + .long secondary_data + .long __secondary_switched +#endif /* defined(CONFIG_SMP) */ @@ -228,13 +204,12 @@ __turn_mmu_on: * r10 = procinfo * * Returns: - * r0, r3, r5, r6, r7 corrupted + * r0, r3, r6, r7 corrupted * r4 = physical page table address */ .type __create_page_tables, %function __create_page_tables: - ldr r5, [r8, #MACHINFO_PHYSRAM] @ physram - pgtbl r4, r5 @ page table address + pgtbl r4 @ page table address /* * Clear the 16K level 1 swapper page table @@ -249,7 +224,7 @@ __create_page_tables: teq r0, r6 bne 1b - ldr r7, [r10, #PROCINFO_MMUFLAGS] @ mmuflags + ldr r7, [r10, #PROCINFO_MM_MMUFLAGS] @ mm_mmuflags /* * Create identity mapping for first MB of kernel to @@ -263,24 +238,25 @@ __create_page_tables: /* * Now setup the pagetables for our kernel direct - * mapped region. We round TEXTADDR down to the - * nearest megabyte boundary. It is assumed that - * the kernel fits within 4 contigous 1MB sections. + * mapped region. */ add r0, r4, #(TEXTADDR & 0xff000000) >> 18 @ start of kernel str r3, [r0, #(TEXTADDR & 0x00f00000) >> 18]! - add r3, r3, #1 << 20 - str r3, [r0, #4]! @ KERNEL + 1MB - add r3, r3, #1 << 20 - str r3, [r0, #4]! @ KERNEL + 2MB - add r3, r3, #1 << 20 - str r3, [r0, #4] @ KERNEL + 3MB + + ldr r6, =(_end - PAGE_OFFSET - 1) @ r6 = number of sections + mov r6, r6, lsr #20 @ needed for kernel minus 1 + +1: add r3, r3, #1 << 20 + str r3, [r0, #4]! + subs r6, r6, #1 + bgt 1b /* * Then map first 1MB of ram in case it contains our boot params. */ - add r0, r4, #VIRT_OFFSET >> 18 - orr r6, r5, r7 + add r0, r4, #PAGE_OFFSET >> 18 + orr r6, r7, #(PHYS_OFFSET & 0xff000000) + orr r6, r6, #(PHYS_OFFSET & 0x00e00000) str r6, [r0] #ifdef CONFIG_XIP_KERNEL @@ -288,7 +264,7 @@ __create_page_tables: * Map some ram to cover our .data and .bss areas. * Mapping 3MB should be plenty. */ - sub r3, r4, r5 + sub r3, r4, #PHYS_OFFSET mov r3, r3, lsr #20 add r0, r0, r3, lsl #2 add r6, r6, r3, lsl #20 @@ -299,9 +275,8 @@ __create_page_tables: str r6, [r0] #endif - bic r7, r7, #0x0c @ turn off cacheable - @ and bufferable bits #ifdef CONFIG_DEBUG_LL + ldr r7, [r10, #PROCINFO_IO_MMUFLAGS] @ io_mmuflags /* * Map in IO space for serial debugging. * This allows debug messages to be output @@ -321,20 +296,12 @@ __create_page_tables: bne 1b #if defined(CONFIG_ARCH_NETWINDER) || defined(CONFIG_ARCH_CATS) /* - * If we're using the NetWinder, we need to map in - * the 16550-type serial port for the debug messages + * If we're using the NetWinder or CATS, we also need to map + * in the 16550-type serial port for the debug messages */ - teq r1, #MACH_TYPE_NETWINDER - teqne r1, #MACH_TYPE_CATS - bne 1f - add r0, r4, #0x3fc0 @ ff000000 - mov r3, #0x7c000000 - orr r3, r3, r7 - str r3, [r0], #4 - add r3, r3, #1 << 20 - str r3, [r0], #4 -1: -#endif + add r0, r4, #0xff000000 >> 18 + orr r3, r7, #0x7c000000 + str r3, [r0] #endif #ifdef CONFIG_ARCH_RPC /* @@ -342,144 +309,14 @@ __create_page_tables: * Similar reasons here - for debug. This is * only for Acorn RiscPC architectures. */ - add r0, r4, #0x80 @ 02000000 - mov r3, #0x02000000 - orr r3, r3, r7 + add r0, r4, #0x02000000 >> 18 + orr r3, r7, #0x02000000 str r3, [r0] - add r0, r4, #0x3600 @ d8000000 + add r0, r4, #0xd8000000 >> 18 str r3, [r0] +#endif #endif mov pc, lr .ltorg - - -/* - * 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 - * we're even running on the right architecture, we do virtually nothing. - * - * r0 = ascii error character: - * a = invalid architecture - * p = invalid processor - * i = invalid calling convention - * - * Generally, only serious errors cause this. - */ - .type __error, %function -__error: -#ifdef CONFIG_DEBUG_LL - mov r8, r0 @ preserve r0 - adr r0, err_str - bl printascii - mov r0, r8 - bl printch -#endif -#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 - -#ifdef CONFIG_DEBUG_LL - .type err_str, %object -err_str: - .asciz "\nError: " - .align -#endif - -/* - * 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. - * - * Returns: - * r3, r4, r6 corrupted - * r5 = proc_info pointer in physical address space - * r9 = cpuid - */ - .type __lookup_processor_type, %function -__lookup_processor_type: - adr r3, 3f - ldmda r3, {r5, r6, r9} - sub r3, r3, r9 @ get offset between virt&phys - add r5, r5, r3 @ convert virt addresses to - add r6, r6, r3 @ physical address space - mrc p15, 0, r9, c0, c0 @ get processor id -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 - blt 1b - mov r5, #0 @ unknown processor -2: mov pc, lr - -/* - * This provides a C-API version of the above function. - */ -ENTRY(lookup_processor_type) - stmfd sp!, {r4 - r6, r9, lr} - bl __lookup_processor_type - mov r0, r5 - ldmfd sp!, {r4 - r6, r9, pc} - -/* - * Look in include/asm-arm/procinfo.h and arch/arm/kernel/arch.[ch] for - * more information about the __proc_info and __arch_info structures. - */ - .long __proc_info_begin - .long __proc_info_end -3: .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 - * 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 - */ - .type __lookup_machine_type, %function -__lookup_machine_type: - adr r3, 3b - 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] @ get machine type - teq r3, r1 @ matches loader number? - beq 2f @ found - add r5, r5, #SIZEOF_MACHINE_DESC @ next machine_desc - cmp r5, r6 - blt 1b - mov r5, #0 @ unknown machine -2: mov pc, lr - -/* - * This provides a C-API version of the above function. - */ -ENTRY(lookup_machine_type) - stmfd sp!, {r4 - r6, lr} - mov r1, r0 - bl __lookup_machine_type - mov r0, r5 - ldmfd sp!, {r4 - r6, pc} +#include "head-common.S"