diff options
Diffstat (limited to 'u-boot/arch/arm/cpu/pxa/start.S')
| -rw-r--r-- | u-boot/arch/arm/cpu/pxa/start.S | 603 |
1 files changed, 603 insertions, 0 deletions
diff --git a/u-boot/arch/arm/cpu/pxa/start.S b/u-boot/arch/arm/cpu/pxa/start.S new file mode 100644 index 0000000..d2d391e --- /dev/null +++ b/u-boot/arch/arm/cpu/pxa/start.S @@ -0,0 +1,603 @@ +/* + * armboot - Startup Code for XScale + * + * Copyright (C) 1998 Dan Malek <dmalek@jlc.net> + * Copyright (C) 1999 Magnus Damm <kieraypc01.p.y.kie.era.ericsson.se> + * Copyright (C) 2000 Wolfgang Denk <wd@denx.de> + * Copyright (C) 2001 Alex Zuepke <azu@sysgo.de> + * Copyright (C) 2002 Kyle Harris <kharris@nexus-tech.net> + * Copyright (C) 2003 Robert Schwebel <r.schwebel@pengutronix.de> + * Copyright (C) 2003 Kai-Uwe Bloem <kai-uwe.bloem@auerswald.de> + * Copyright (c) 2010 Marek Vasut <marek.vasut@gmail.com> + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include <asm-offsets.h> +#include <config.h> +#include <version.h> +#include <asm/arch/pxa-regs.h> + +/* takes care the CP15 update has taken place */ +.macro CPWAIT reg +mrc p15,0,\reg,c2,c0,0 +mov \reg,\reg +sub pc,pc,#4 +.endm + +.globl _start +_start: b reset +#ifdef CONFIG_PRELOADER + ldr pc, _hang + ldr pc, _hang + ldr pc, _hang + ldr pc, _hang + ldr pc, _hang + ldr pc, _hang + ldr pc, _hang + +_hang: + .word do_hang + .word 0x12345678 + .word 0x12345678 + .word 0x12345678 + .word 0x12345678 + .word 0x12345678 + .word 0x12345678 + .word 0x12345678 /* now 16*4=64 */ +#else + ldr pc, _undefined_instruction + ldr pc, _software_interrupt + ldr pc, _prefetch_abort + ldr pc, _data_abort + ldr pc, _not_used + ldr pc, _irq + ldr pc, _fiq + +_undefined_instruction: .word undefined_instruction +_software_interrupt: .word software_interrupt +_prefetch_abort: .word prefetch_abort +_data_abort: .word data_abort +_not_used: .word not_used +_irq: .word irq +_fiq: .word fiq +#endif /* CONFIG_PRELOADER */ + + .balignl 16,0xdeadbeef + + +/* + * Startup Code (reset vector) + * + * do important init only if we don't start from RAM! + * - relocate armboot to RAM + * - setup stack + * - jump to second stage + */ + +.globl _TEXT_BASE +_TEXT_BASE: + .word CONFIG_SYS_TEXT_BASE + +/* + * These are defined in the board-specific linker script. + */ +.globl _bss_start_ofs +_bss_start_ofs: + .word __bss_start - _start + +.globl _bss_end_ofs +_bss_end_ofs: + .word _end - _start + +#ifdef CONFIG_USE_IRQ +/* IRQ stack memory (calculated at run-time) */ +.globl IRQ_STACK_START +IRQ_STACK_START: + .word 0x0badc0de + +/* IRQ stack memory (calculated at run-time) */ +.globl FIQ_STACK_START +FIQ_STACK_START: + .word 0x0badc0de +#endif /* CONFIG_USE_IRQ */ + +#ifndef CONFIG_PRELOADER +/* IRQ stack memory (calculated at run-time) + 8 bytes */ +.globl IRQ_STACK_START_IN +IRQ_STACK_START_IN: + .word 0x0badc0de + +/* + * the actual reset code + */ + +reset: + /* + * set the cpu to SVC32 mode + */ + mrs r0,cpsr + bic r0,r0,#0x1f + orr r0,r0,#0xd3 + msr cpsr,r0 + + /* + * Enable MMU to use DCache as DRAM + */ + /* Domain access -- enable for all CPs */ + ldr r0, =0x0000ffff + mcr p15, 0, r0, c3, c0, 0 + + /* Point TTBR to MMU table */ + ldr r0, =mmu_table + adr r2, _start + orr r0, r2 + mcr p15, 0, r0, c2, c0, 0 + +/* !!! Hereby, check if the code is running from SRAM !!! */ +/* If the code is running from SRAM, alias SRAM to 0x0 to simulate NOR. The code + * is linked to 0x0 too, so this makes things easier. */ + cmp r2, #0x5c000000 + + ldreq r1, [r0] + orreq r1, r2 + streq r1, [r0] + + /* Kick in MMU, ICache, DCache, BTB */ + mrc p15, 0, r0, c1, c0, 0 + bic r0, #0x1b00 + bic r0, #0x0087 + orr r0, #0x1800 + orr r0, #0x0005 + mcr p15, 0, r0, c1, c0, 0 + CPWAIT r0 + + /* Unlock Icache, Dcache */ + mcr p15, 0, r0, c9, c1, 1 + mcr p15, 0, r0, c9, c2, 1 + + /* Flush Icache, Dcache, BTB */ + mcr p15, 0, r0, c7, c7, 0 + + /* Unlock I-TLB, D-TLB */ + mcr p15, 0, r0, c10, c4, 1 + mcr p15, 0, r0, c10, c8, 1 + + /* Flush TLB */ + mcr p15, 0, r0, c8, c7, 0 + /* Allocate 4096 bytes of Dcache as RAM */ + + /* Drain pending loads and stores */ + mcr p15, 0, r0, c7, c10, 4 + + mov r4, #0x00 + mov r5, #0x00 + mov r2, #0x01 + mcr p15, 0, r0, c9, c2, 0 + CPWAIT r0 + + /* 128 lines reserved (128 x 32bytes = 4096 bytes total) */ + mov r0, #128 + mov r1, #0xa0000000 +alloc: + mcr p15, 0, r1, c7, c2, 5 + /* Drain pending loads and stores */ + mcr p15, 0, r0, c7, c10, 4 + strd r4, [r1], #8 + strd r4, [r1], #8 + strd r4, [r1], #8 + strd r4, [r1], #8 + subs r0, #0x01 + bne alloc + /* Drain pending loads and stores */ + mcr p15, 0, r0, c7, c10, 4 + mov r2, #0x00 + mcr p15, 0, r2, c9, c2, 0 + CPWAIT r0 + + /* Jump to 0x0 ( + offset) if running from SRAM */ + adr r0, zerojmp + bic r0, #0x5c000000 + mov pc, r0 +zerojmp: + +/* Set stackpointer in internal RAM to call board_init_f */ +call_board_init_f: + ldr sp, =(CONFIG_SYS_INIT_SP_ADDR) + bic sp, sp, #7 /* 8-byte alignment for ABI compliance */ + ldr r0,=0x00000000 + bl board_init_f + +/*------------------------------------------------------------------------------*/ + +/* + * void relocate_code (addr_sp, gd, addr_moni) + * + * This "function" does not return, instead it continues in RAM + * after relocating the monitor code. + * + */ + .globl relocate_code +relocate_code: + mov r4, r0 /* save addr_sp */ + mov r5, r1 /* save addr of gd */ + mov r6, r2 /* save addr of destination */ + + /* Set up the stack */ +stack_setup: + mov sp, r4 + + adr r0, _start + cmp r0, r6 + beq clear_bss /* skip relocation */ + mov r1, r6 /* r1 <- scratch for copy_loop */ + ldr r3, _bss_start_ofs + add r2, r0, r3 /* r2 <- source end address */ + + stmfd sp!, {r0-r12} +copy_loop: + ldmia r0!, {r3-r5, r7-r11} /* copy from source address [r0] */ + stmia r1!, {r3-r5, r7-r11} /* copy to target address [r1] */ + cmp r0, r2 /* until source end address [r2] */ + blo copy_loop + ldmfd sp!, {r0-r12} + +#ifndef CONFIG_PRELOADER + /* + * fix .rel.dyn relocations + */ + ldr r0, _TEXT_BASE /* r0 <- Text base */ + sub r9, r6, r0 /* r9 <- relocation offset */ + ldr r10, _dynsym_start_ofs /* r10 <- sym table ofs */ + add r10, r10, r0 /* r10 <- sym table in FLASH */ + ldr r2, _rel_dyn_start_ofs /* r2 <- rel dyn start ofs */ + add r2, r2, r0 /* r2 <- rel dyn start in FLASH */ + ldr r3, _rel_dyn_end_ofs /* r3 <- rel dyn end ofs */ + add r3, r3, r0 /* r3 <- rel dyn end in FLASH */ +fixloop: + ldr r0, [r2] /* r0 <- location to fix up, IN FLASH! */ + add r0, r9 /* r0 <- location to fix up in RAM */ + ldr r1, [r2, #4] + and r7, r1, #0xff + cmp r7, #23 /* relative fixup? */ + beq fixrel + cmp r7, #2 /* absolute fixup? */ + beq fixabs + /* ignore unknown type of fixup */ + b fixnext +fixabs: + /* absolute fix: set location to (offset) symbol value */ + mov r1, r1, LSR #4 /* r1 <- symbol index in .dynsym */ + add r1, r10, r1 /* r1 <- address of symbol in table */ + ldr r1, [r1, #4] /* r1 <- symbol value */ + add r1, r1, r9 /* r1 <- relocated sym addr */ + b fixnext +fixrel: + /* relative fix: increase location by offset */ + ldr r1, [r0] + add r1, r1, r9 +fixnext: + str r1, [r0] + add r2, r2, #8 /* each rel.dyn entry is 8 bytes */ + cmp r2, r3 + blo fixloop +#endif /* #ifndef CONFIG_PRELOADER */ + +clear_bss: +#ifndef CONFIG_PRELOADER + ldr r0, _bss_start_ofs + ldr r1, _bss_end_ofs + mov r4, r6 /* reloc addr */ + add r0, r0, r4 + add r1, r1, r4 + mov r2, #0x00000000 /* clear */ + +clbss_l:str r2, [r0] /* clear loop... */ + add r0, r0, #4 + cmp r0, r1 + bne clbss_l +#endif /* #ifndef CONFIG_PRELOADER */ + +/* + * We are done. Do not return, instead branch to second part of board + * initialization, now running from RAM. + */ +#ifdef CONFIG_ONENAND_IPL + ldr r0, _start_oneboot_ofs + mov pc, r0 + +_start_oneboot_ofs + : .word start_oneboot +#else + ldr r0, _board_init_r_ofs + adr r1, _start + add lr, r0, r1 + add lr, lr, r9 + /* setup parameters for board_init_r */ + mov r0, r5 /* gd_t */ + mov r1, r6 /* dest_addr */ + /* jump to it ... */ + mov pc, lr + +_board_init_r_ofs: + .word board_init_r - _start +#endif /* CONFIG_ONENAND_IPL */ + +_rel_dyn_start_ofs: + .word __rel_dyn_start - _start +_rel_dyn_end_ofs: + .word __rel_dyn_end - _start +_dynsym_start_ofs: + .word __dynsym_start - _start + +#else /* CONFIG_PRELOADER */ + +/****************************************************************************/ +/* */ +/* the actual reset code for OneNAND IPL */ +/* */ +/****************************************************************************/ + +#ifndef CONFIG_PXA27X +#error OneNAND IPL is not supported on PXA25x and 26x due to lack of SRAM +#endif + +reset: + /* Set CPU to SVC32 mode */ + mrs r0,cpsr + bic r0,r0,#0x1f + orr r0,r0,#0x13 + msr cpsr,r0 + + /* Point stack at the end of SRAM and leave 32 words for abort-stack */ + ldr sp, =0x5c03ff80 + + /* Start OneNAND IPL */ + ldr pc, =start_oneboot + +#endif /* CONFIG_PRELOADER */ + +#ifndef CONFIG_PRELOADER +/****************************************************************************/ +/* */ +/* Interrupt handling */ +/* */ +/****************************************************************************/ + +/* IRQ stack frame */ + +#define S_FRAME_SIZE 72 + +#define S_OLD_R0 68 +#define S_PSR 64 +#define S_PC 60 +#define S_LR 56 +#define S_SP 52 + +#define S_IP 48 +#define S_FP 44 +#define S_R10 40 +#define S_R9 36 +#define S_R8 32 +#define S_R7 28 +#define S_R6 24 +#define S_R5 20 +#define S_R4 16 +#define S_R3 12 +#define S_R2 8 +#define S_R1 4 +#define S_R0 0 + +#define MODE_SVC 0x13 + + /* use bad_save_user_regs for abort/prefetch/undef/swi ... */ + + .macro bad_save_user_regs + sub sp, sp, #S_FRAME_SIZE + stmia sp, {r0 - r12} /* Calling r0-r12 */ + add r8, sp, #S_PC + + ldr r2, IRQ_STACK_START_IN + ldmia r2, {r2 - r4} /* get pc, cpsr, old_r0 */ + add r0, sp, #S_FRAME_SIZE /* restore sp_SVC */ + + add r5, sp, #S_SP + mov r1, lr + stmia r5, {r0 - r4} /* save sp_SVC, lr_SVC, pc, cpsr, old_r */ + mov r0, sp + .endm + + + /* use irq_save_user_regs / irq_restore_user_regs for */ + /* IRQ/FIQ handling */ + + .macro irq_save_user_regs + sub sp, sp, #S_FRAME_SIZE + stmia sp, {r0 - r12} /* Calling r0-r12 */ + add r8, sp, #S_PC + stmdb r8, {sp, lr}^ /* Calling SP, LR */ + str lr, [r8, #0] /* Save calling PC */ + mrs r6, spsr + str r6, [r8, #4] /* Save CPSR */ + str r0, [r8, #8] /* Save OLD_R0 */ + mov r0, sp + .endm + + .macro irq_restore_user_regs + ldmia sp, {r0 - lr}^ @ Calling r0 - lr + mov r0, r0 + ldr lr, [sp, #S_PC] @ Get PC + add sp, sp, #S_FRAME_SIZE + subs pc, lr, #4 @ return & move spsr_svc into cpsr + .endm + + .macro get_bad_stack + ldr r13, IRQ_STACK_START_IN @ setup our mode stack + + str lr, [r13] @ save caller lr / spsr + mrs lr, spsr + str lr, [r13, #4] + + mov r13, #MODE_SVC @ prepare SVC-Mode + msr spsr_c, r13 + mov lr, pc + movs pc, lr + .endm + + .macro get_irq_stack @ setup IRQ stack + ldr sp, IRQ_STACK_START + .endm + + .macro get_fiq_stack @ setup FIQ stack + ldr sp, FIQ_STACK_START + .endm +#endif /* CONFIG_PRELOADER + + +/****************************************************************************/ +/* */ +/* exception handlers */ +/* */ +/****************************************************************************/ + +#ifdef CONFIG_PRELOADER + .align 5 +do_hang: + ldr sp, _TEXT_BASE /* use 32 words abort stack */ + bl hang /* hang and never return */ +#else + .align 5 +undefined_instruction: + get_bad_stack + bad_save_user_regs + bl do_undefined_instruction + + .align 5 +software_interrupt: + get_bad_stack + bad_save_user_regs + bl do_software_interrupt + + .align 5 +prefetch_abort: + get_bad_stack + bad_save_user_regs + bl do_prefetch_abort + + .align 5 +data_abort: + get_bad_stack + bad_save_user_regs + bl do_data_abort + + .align 5 +not_used: + get_bad_stack + bad_save_user_regs + bl do_not_used + +#ifdef CONFIG_USE_IRQ + + .align 5 +irq: + get_irq_stack + irq_save_user_regs + bl do_irq + irq_restore_user_regs + + .align 5 +fiq: + get_fiq_stack + irq_save_user_regs /* someone ought to write a more */ + bl do_fiq /* effiction fiq_save_user_regs */ + irq_restore_user_regs + +#else /* !CONFIG_USE_IRQ */ + + .align 5 +irq: + get_bad_stack + bad_save_user_regs + bl do_irq + + .align 5 +fiq: + get_bad_stack + bad_save_user_regs + bl do_fiq +#endif /* CONFIG_PRELOADER */ +#endif /* CONFIG_USE_IRQ */ + +/****************************************************************************/ +/* */ +/* Reset function: the PXA250 doesn't have a reset function, so we have to */ +/* perform a watchdog timeout for a soft reset. */ +/* */ +/****************************************************************************/ +/* Operating System Timer */ +.align 5 +.globl reset_cpu + + /* FIXME: this code is PXA250 specific. How is this handled on */ + /* other XScale processors? */ + +reset_cpu: + + /* We set OWE:WME (watchdog enable) and wait until timeout happens */ + + ldr r0, =OWER + ldr r1, [r0] + orr r1, r1, #0x0001 /* bit0: WME */ + str r1, [r0] + + /* OS timer does only wrap every 1165 seconds, so we have to set */ + /* the match register as well. */ + + ldr r0, =OSCR + ldr r1, [r0] /* read OS timer */ + add r1, r1, #0x800 /* let OSMR3 match after */ + add r1, r1, #0x800 /* 4096*(1/3.6864MHz)=1ms */ + ldr r0, =OSMR3 + str r1, [r0] + +reset_endless: + + b reset_endless + +#ifndef CONFIG_PRELOADER +.section .mmudata, "a" + .align 14 + .globl mmu_table +mmu_table: + /* 0x00000000 - 0xa0000000 : 1:1, uncached mapping */ + .set __base, 0 + .rept 0xa00 + .word (__base << 20) | 0xc12 + .set __base, __base + 1 + .endr + + /* 0xa0000000 - 0xa0100000 : 1:1, cached mapping */ + .word (0xa00 << 20) | 0x1c1e + + .set __base, 0xa01 + .rept 0x1000 - 0xa01 + .word (__base << 20) | 0xc12 + .set __base, __base + 1 + .endr +#endif /* CONFIG_PRELOADER */ |