The start.S on PXA was very obscure. This reworks it back to be close to arm1136 start.S and others.
Signed-off-by: Marek Vasut marek.vasut@gmail.com Cc: Albert ARIBAUD albert.u.boot@aribaud.net --- arch/arm/cpu/pxa/cpu.c | 16 ++ arch/arm/cpu/pxa/start.S | 382 ++++++++++++++++----------------------------- 2 files changed, 152 insertions(+), 246 deletions(-)
diff --git a/arch/arm/cpu/pxa/cpu.c b/arch/arm/cpu/pxa/cpu.c index df351c7..c48b2ef 100644 --- a/arch/arm/cpu/pxa/cpu.c +++ b/arch/arm/cpu/pxa/cpu.c @@ -328,3 +328,19 @@ void i2c_clk_enable(void) writel(readl(CKEN) | CKEN14_I2C, CKEN); #endif } + +void reset_cpu(ulong ignored) __attribute__((noreturn)); + +void reset_cpu(ulong ignored) +{ + uint32_t tmp; + + setbits_le32(OWER, OWER_WME); + + tmp = readl(OSCR); + tmp += 0x1000; + writel(tmp, OSMR3); + + for (;;) + ; +} diff --git a/arch/arm/cpu/pxa/start.S b/arch/arm/cpu/pxa/start.S index 6191a73..46f7ac0 100644 --- a/arch/arm/cpu/pxa/start.S +++ b/arch/arm/cpu/pxa/start.S @@ -1,14 +1,20 @@ /* - * armboot - Startup Code for XScale + * armboot - Startup Code for XScale CPU-core * * 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) 2001 Marius Groger mag@sysgo.de + * Copyright (C) 2002 Alex Zupke azu@sysgo.de + * Copyright (C) 2002 Gary Jennejohn garyj@denx.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 + * Copyright (C) 2003 Kshitij kshitij@ti.com + * Copyright (C) 2003 Richard Woodruff r-woodruff2@ti.com + * Copyright (C) 2003 Robert Schwebel r.schwebel@pengutronix.de + * Copyright (C) 2004 Texas Instruments r-woodruff2@ti.com + * Copyright (C) 2010 Marek Vasut marek.vasut@gmail.com * * See file CREDITS for list of people who contributed to this * project. @@ -32,15 +38,6 @@ #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_SPL_BUILD @@ -77,26 +74,38 @@ _data_abort: .word data_abort _not_used: .word not_used _irq: .word irq _fiq: .word fiq +_pad: .word 0x12345678 /* now 16*4=64 */ #endif /* CONFIG_SPL_BUILD */ +.global _end_vect +_end_vect:
.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 + * do important init only if we don't start from memory! + * setup Memory and board specific bits prior to relocation. + * relocate armboot to ram + * setup stack + * + ************************************************************************* */
.globl _TEXT_BASE _TEXT_BASE: +#ifdef CONFIG_SPL_BUILD + .word CONFIG_SPL_TEXT_BASE +#else .word CONFIG_SYS_TEXT_BASE +#endif
/* * These are defined in the board-specific linker script. + * Subtracting _start from them lets the linker put their + * relative position in the executable instead of leaving + * them null. */ .globl _bss_start_ofs _bss_start_ofs: @@ -120,9 +129,8 @@ IRQ_STACK_START: .globl FIQ_STACK_START FIQ_STACK_START: .word 0x0badc0de -#endif /* CONFIG_USE_IRQ */ +#endif
-#ifndef CONFIG_SPL_BUILD /* IRQ stack memory (calculated at run-time) + 8 bytes */ .globl IRQ_STACK_START_IN IRQ_STACK_START_IN: @@ -141,91 +149,15 @@ reset: 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: +#ifndef CONFIG_SKIP_LOWLEVEL_INIT + bl cpu_init_crit +#endif
/* 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 + ldr r0, =0x00000000 bl board_init_f
/*------------------------------------------------------------------------------*/ @@ -254,13 +186,11 @@ stack_setup: 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] */ + ldmia r0!, {r9-r10} /* copy from source address [r0] */ + stmia r1!, {r9-r10} /* copy to target address [r1] */ cmp r0, r2 /* until source end address [r2] */ blo copy_loop - ldmfd sp!, {r0-r12}
#ifndef CONFIG_SPL_BUILD /* @@ -275,13 +205,13 @@ copy_loop: 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 r0, [r2] /* r0 <- location to fix up, IN FLASH! */ + add r0, r0, r9 /* r0 <- location to fix up in RAM */ ldr r1, [r2, #4] and r7, r1, #0xff - cmp r7, #23 /* relative fixup? */ + cmp r7, #23 /* relative fixup? */ beq fixrel - cmp r7, #2 /* absolute fixup? */ + cmp r7, #2 /* absolute fixup? */ beq fixabs /* ignore unknown type of fixup */ b fixnext @@ -298,10 +228,10 @@ fixrel: add r1, r1, r9 fixnext: str r1, [r0] - add r2, r2, #8 /* each rel.dyn entry is 8 bytes */ + add r2, r2, #8 /* each rel.dyn entry is 8 bytes */ cmp r2, r3 blo fixloop -#endif /* #ifndef CONFIG_SPL_BUILD */ +#endif
clear_bss: #ifndef CONFIG_SPL_BUILD @@ -322,15 +252,16 @@ clbss_l:str r2, [r0] /* clear loop... */ * 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 +#ifdef CONFIG_ONENAND_SPL + ldr r0, _onenand_boot_ofs mov pc, r0
-_start_oneboot_ofs - : .word start_oneboot +_onenand_boot_ofs: + .word onenand_boot #else +jump_2_ram: ldr r0, _board_init_r_ofs - adr r1, _start + ldr r1, _TEXT_BASE add lr, r0, r1 add lr, lr, r9 /* setup parameters for board_init_r */ @@ -341,7 +272,7 @@ _start_oneboot_ofs
_board_init_r_ofs: .word board_init_r - _start -#endif /* CONFIG_ONENAND_IPL */ +#endif
_rel_dyn_start_ofs: .word __rel_dyn_start - _start @@ -350,42 +281,49 @@ _rel_dyn_end_ofs: _dynsym_start_ofs: .word __dynsym_start - _start
-#else /* CONFIG_SPL_BUILD */ - -/****************************************************************************/ -/* */ -/* 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 +/* + ************************************************************************* + * + * CPU_init_critical registers + * + * setup important registers + * setup memory timing + * + ************************************************************************* + */ +#ifndef CONFIG_SKIP_LOWLEVEL_INIT +cpu_init_crit: + /* + * flush v4 I/D caches + */ + mov r0, #0 + mcr p15, 0, r0, c7, c7, 0 /* Invalidate I+D+BTB caches */ + mcr p15, 0, r0, c8, c7, 0 /* Invalidate Unified TLB */
- /* Start OneNAND IPL */ - ldr pc, =start_oneboot + /* + * disable MMU stuff and caches + */ + mrc p15, 0, r0, c1, c0, 0 + bic r0, r0, #0x00002300 @ clear bits 13, 9:8 (--V- --RS) + bic r0, r0, #0x00000087 @ clear bits 7, 2:0 (B--- -CAM) + orr r0, r0, #0x00000002 @ set bit 2 (A) Align + orr r0, r0, #0x00001000 @ set bit 12 (I) I-Cache + mcr p15, 0, r0, c1, c0, 0
-#endif /* CONFIG_SPL_BUILD */ + mov pc, lr /* back to my caller */ +#endif /* CONFIG_SKIP_LOWLEVEL_INIT */
#ifndef CONFIG_SPL_BUILD -/****************************************************************************/ -/* */ -/* Interrupt handling */ -/* */ -/****************************************************************************/ - -/* IRQ stack frame */ - +/* + ************************************************************************* + * + * Interrupt handling + * + ************************************************************************* + */ +@ +@ IRQ stack frame. +@ #define S_FRAME_SIZE 72
#define S_OLD_R0 68 @@ -409,37 +347,36 @@ reset: #define S_R0 0
#define MODE_SVC 0x13 +#define I_BIT 0x80
- /* use bad_save_user_regs for abort/prefetch/undef/swi ... */ +/* + * use bad_save_user_regs for abort/prefetch/undef/swi ... + * use irq_save_user_regs / irq_restore_user_regs for IRQ/FIQ handling + */
.macro bad_save_user_regs - sub sp, sp, #S_FRAME_SIZE - stmia sp, {r0 - r12} /* Calling r0-r12 */ - add r8, sp, #S_PC + sub sp, sp, #S_FRAME_SIZE @ carve out a frame on current user stack + stmia sp, {r0 - r12} @ Save user registers (now in svc mode) r0-r12
- ldr r2, IRQ_STACK_START_IN - ldmia r2, {r2 - r4} /* get pc, cpsr, old_r0 */ - add r0, sp, #S_FRAME_SIZE /* restore sp_SVC */ + ldr r2, IRQ_STACK_START_IN @ set base 2 words into abort stack + ldmia r2, {r2 - r3} @ get values for "aborted" pc and cpsr (into parm regs) + add r0, sp, #S_FRAME_SIZE @ grab pointer to old stack
add r5, sp, #S_SP mov r1, lr - stmia r5, {r0 - r4} /* save sp_SVC, lr_SVC, pc, cpsr, old_r */ - mov r0, sp + stmia r5, {r0 - r3} @ save sp_SVC, lr_SVC, pc, cpsr + mov r0, sp @ save current stack into r0 (param register) .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 */ + stmia sp, {r0 - r12} @ Calling r0-r12 + add r8, sp, #S_PC @ !!!! R8 NEEDS to be saved !!!! a reserved stack spot would be good. + 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 */ + str r6, [r8, #4] @ Save CPSR + str r0, [r8, #8] @ Save OLD_R0 mov r0, sp .endm
@@ -452,16 +389,28 @@ reset: .endm
.macro get_bad_stack - ldr r13, IRQ_STACK_START_IN @ setup our mode stack + ldr r13, IRQ_STACK_START_IN @ setup our mode stack (enter in banked mode)
- str lr, [r13] @ save caller lr / spsr - mrs lr, spsr - str lr, [r13, #4] + str lr, [r13] @ save caller lr in position 0 of saved stack + mrs lr, spsr @ get the spsr + str lr, [r13, #4] @ save spsr in position 1 of saved stack
mov r13, #MODE_SVC @ prepare SVC-Mode - msr spsr_c, r13 - mov lr, pc - movs pc, lr + @ msr spsr_c, r13 + msr spsr, r13 @ switch modes, make sure moves will execute + mov lr, pc @ capture return pc + movs pc, lr @ jump to next instruction & switch modes. + .endm + + .macro get_bad_stack_swi + sub r13, r13, #4 @ space on current stack for scratch reg. + str r0, [r13] @ save R0's value. + ldr r0, IRQ_STACK_START_IN @ get data regions start + str lr, [r0] @ save caller lr in position 0 of saved stack + mrs r0, spsr @ get the spsr + str lr, [r0, #4] @ save spsr in position 1 of saved stack + ldr r0, [r13] @ restore r0 + add r13, r13, #4 @ pop stack entry .endm
.macro get_irq_stack @ setup IRQ stack @@ -471,21 +420,17 @@ reset: .macro get_fiq_stack @ setup FIQ stack ldr sp, FIQ_STACK_START .endm -#endif /* CONFIG_SPL_BUILD - - -/****************************************************************************/ -/* */ -/* exception handlers */ -/* */ -/****************************************************************************/ +#endif /* CONFIG_SPL_BUILD */
+/* + * exception handlers + */ #ifdef CONFIG_SPL_BUILD .align 5 do_hang: - ldr sp, _TEXT_BASE /* use 32 words abort stack */ + ldr sp, _TEXT_BASE /* use 32 words about stack */ bl hang /* hang and never return */ -#else +#else /* !CONFIG_SPL_BUILD */ .align 5 undefined_instruction: get_bad_stack @@ -494,7 +439,7 @@ undefined_instruction:
.align 5 software_interrupt: - get_bad_stack + get_bad_stack_swi bad_save_user_regs bl do_software_interrupt
@@ -528,11 +473,12 @@ irq: .align 5 fiq: get_fiq_stack - irq_save_user_regs /* someone ought to write a more */ - bl do_fiq /* effiction fiq_save_user_regs */ + /* someone ought to write a more effiction fiq_save_user_regs */ + irq_save_user_regs + bl do_fiq irq_restore_user_regs
-#else /* !CONFIG_USE_IRQ */ +#else
.align 5 irq: @@ -545,63 +491,7 @@ fiq: get_bad_stack bad_save_user_regs bl do_fiq -#endif /* CONFIG_SPL_BUILD */ -#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_SPL_BUILD -.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 + .align 5 #endif /* CONFIG_SPL_BUILD */