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authorDaniel Ankers <dan@weirdo.org.uk>2006-09-01 09:54:08 +0000
committerDaniel Ankers <dan@weirdo.org.uk>2006-09-01 09:54:08 +0000
commit47e4f6ce4878314d386512d611c428be7ea26787 (patch)
tree12055e277de497d427e8e4dc0d4b5e364f899fa7
parent2ad7b6b71fb5d1f6b6f4c978e6b70ba8723d2f52 (diff)
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Remove unneeded code from firmware/crt0.S
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@10842 a1c6a512-1295-4272-9138-f99709370657
-rw-r--r--firmware/crt0.S848
1 files changed, 5 insertions, 843 deletions
diff --git a/firmware/crt0.S b/firmware/crt0.S
index 96e08be..61a2d63 100644
--- a/firmware/crt0.S
+++ b/firmware/crt0.S
@@ -16,432 +16,21 @@
* KIND, either express or implied.
*
****************************************************************************/
+
+/* Most of the code from this file has now been moved into the target trees */
+
#include "config.h"
#include "cpu.h"
-#if defined(CPU_ARM)
- .section .init.text,"ax",%progbits
-#else
.section .init.text,"ax",@progbits
-#endif
.global start
start:
-#if defined(CPU_ARM)
-
-/* iPod bootloader and startup code based on startup.s from the iPodLinux loader
- *
- * Copyright (c) 2003, Daniel Palffy (dpalffy (at) rainstorm.org)
- * Copyright (c) 2005, Bernard Leach <leachbj@bouncycastle.org>
- *
- */
- .equ PP5002_PROC_ID, 0xc4000000
- .equ PP5002_COP_CTRL, 0xcf004058
- .equ PP5020_PROC_ID, 0x60000000
- .equ PP5020_COP_CTRL, 0x60007004
-
- msr cpsr_c, #0xd3 /* enter supervisor mode, disable IRQ */
-
-#ifndef BOOTLOADER
-#ifdef CPU_PP
- b pad_skip
-.space 50*4 /* (more than enough) space for exception vectors */
-pad_skip:
- /* We need to remap memory from wherever SDRAM is mapped natively, to
- base address 0, so we can put our exception vectors there. We don't
- want to do this remapping while executing from SDRAM, so we copy the
- remapping code to IRAM, then execute from there. Hence, the following
- code is compiled for address 0, but is currently executing at either
- 0x28000000 or 0x10000000, depending on chipset version. Do not use any
- absolute addresses until remapping has been done. */
- ldr r1, =0x40000000
- ldr r2, =remap_start
- ldr r3, =remap_end
-
- and r5, pc, #0xff000000 /* adjust for execute address */
- orr r2, r2, r5
- orr r3, r3, r5
-
- /* copy the code to 0x40000000 */
-1:
- ldr r4, [r2], #4
- str r4, [r1], #4
- cmp r2, r3
- ble 1b
-
- ldr r3, =0x3f84 /* r3 and r1 values here are magic, don't touch */
- orr r3, r3, r5 /* adjust for execute address */
- ldr r2, =0xf000f014
- mov r1, #0x3a00
- ldr r0, =0xf000f010
- mov pc, #0x40000000
-
-remap_start:
- str r1, [r0]
- str r3, [r2]
- ldr r0, L_post_remap
- mov pc, r0
-L_post_remap: .word remap_end
-remap_end:
-
- /* After doing the remapping, send the COP to sleep.
- On wakeup it will go to cop_init */
-#if CONFIG_CPU == PP5002
- ldr r0, =PP5002_PROC_ID
-#else
- ldr r0, =PP5020_PROC_ID
-#endif
- ldr r0, [r0]
- and r0, r0, #0xff
- cmp r0, #0x55
- beq 1f
-
- /* put us (co-processor) to sleep */
-#if CONFIG_CPU == PP5002
- ldr r4, =PP5002_COP_CTRL
- mov r3, #0xca
-#else
- ldr r4, =PP5020_COP_CTRL
- mov r3, #0x80000000
-#endif
- str r3, [r4]
-
- ldr pc, =cop_init
-
-1:
-
-#elif CONFIG_CPU == PNX0101
-
-#ifndef DEBUG
- ldr r0, =0x80105000
- mov r1, #1
- str r1, [r0, #4]
- mov r1, #0
- str r1, [r0, #4]
-1: ldr r1, [r0]
- cmp r1, #0
- bne 1b
- mov r1, #0x74
- str r1, [r0, #8]
- mov r1, #2
- str r1, [r0, #0x18]
- mov r1, #0x120
- str r1, [r0, #0x30]
- mov r1, #6
- str r1, [r0, #4]
- ldr r0, =1f
- mov r15, r0
-1:
-#endif /* !DEBUG */
-#endif /* chipset specific */
-
-#ifndef DEBUG
- /* Copy exception handler code to address 0 */
- ldr r2, =_vectorsstart
- ldr r3, =_vectorsend
- ldr r4, =_vectorscopy
-1:
- cmp r3, r2
- ldrhi r5, [r4], #4
- strhi r5, [r2], #4
- bhi 1b
-#else
- ldr r1, =vectors
- ldr r0, =irq_handler
- str r0, [r1, #24]
- ldr r0, =fiq_handler
- str r0, [r1, #28]
-#endif
-
-#ifndef STUB
- /* Zero out IBSS */
- ldr r2, =_iedata
- ldr r3, =_iend
- mov r4, #0
-1:
- cmp r3, r2
- strhi r4, [r2], #4
- bhi 1b
-
- /* Copy the IRAM */
- ldr r2, =_iramcopy
- ldr r3, =_iramstart
- ldr r4, =_iramend
-1:
- cmp r4, r3
- ldrhi r5, [r2], #4
- strhi r5, [r3], #4
- bhi 1b
-#endif /* !STUB */
-#endif /* !BOOTLOADER */
-
- /* Initialise bss section to zero */
- ldr r2, =_edata
- ldr r3, =_end
- mov r4, #0
-1:
- cmp r3, r2
- strhi r4, [r2], #4
- bhi 1b
-
- /* Set up some stack and munge it with 0xdeadbeef */
- ldr sp, =stackend
- mov r3, sp
- ldr r2, =stackbegin
- ldr r4, =0xdeadbeef
-1:
- cmp r3, r2
- strhi r4, [r2], #4
- bhi 1b
-
-#ifdef BOOTLOADER
-#ifdef CPU_PP
- /* TODO: the high part of the address is probably dependent on CONFIG_CPU.
- Since we tend to use ifdefs for each chipset target
- anyway, we might as well just hardcode it here.
- */
-
- /* get the high part of our execute address */
- ldr r0, =0xff000000
- and r8, pc, r0 @ r8 is used later
-
-#if CONFIG_CPU==PP5002
- mov r0, #PP5002_PROC_ID
-#else
- mov r0, #PP5020_PROC_ID
-#endif
- ldr r0, [r0]
- and r0, r0, #0xff
- cmp r0, #0x55
- beq 1f
-
- /* put us (co-processor) to sleep */
-#if CONFIG_CPU==PP5002
- ldr r4, =PP5002_COP_CTRL
- mov r3, #0xca
-#else
- ldr r4, =PP5020_COP_CTRL
- mov r3, #0x80000000
-#endif
- str r3, [r4]
-
-
- ldr pc, =cop_wake_start
-
-cop_wake_start:
- /* jump the COP to startup */
- ldr r0, =startup_loc
- ldr pc, [r0]
-
-1:
-
- /* get the high part of our execute address */
- ldr r2, =0xffffff00
- and r4, pc, r2
-
- /* Copy bootloader to safe area - 0x40000000 */
- mov r5, #0x40000000
- ldr r6, = _dataend
- sub r0, r6, r5 /* length of loader */
- add r0, r4, r0 /* r0 points to start of loader */
-1:
- cmp r5, r6
- ldrcc r2, [r4], #4
- strcc r2, [r5], #4
- bcc 1b
-
- ldr pc, =start_loc /* jump to the relocated start_loc: */
-
-start_loc:
-
- /* execute the loader - this will load an image to 0x10000000 */
- bl main
-
- /* The loader only returns if it is loading the Apple firmware or Linux -
- the following code isn't executed when starting Rockbox */
-
- /* save the startup address for the COP */
- ldr r1, =startup_loc
- str r0, [r1]
-
-#if CONFIG_CPU==PP5002
- /* make sure COP is sleeping */
- ldr r4, =0xcf004050
-1:
- ldr r3, [r4]
- ands r3, r3, #0x4000
- beq 1b
-
- /* wake up COP */
- ldr r4, =PP5002_COP_CTRL
- mov r3, #0xce
- strh r3, [r4]
-#else
- /* make sure COP is sleeping */
- ldr r4, =PP5020_COP_CTRL
-1:
- ldr r3, [r4]
- ands r3, r3, #0x80000000
- beq 1b
-
- /* wake up COP */
- @ldr r4, =PP5020_COP_CTRL
- mov r3, #0x0
- str r3, [r4]
-#endif
- /* jump to start location */
- mov pc, r0
-
-startup_loc:
- .word 0x0
-
-.align 8 /* starts at 0x100 */
-.global boot_table
-boot_table:
- /* here comes the boot table, don't move its offset */
- .space 400
-#endif /* PP specific */
-/* Code for ARM bootloader targets other than iPod go here */
-
-#if CONFIG_CPU == S3C2440
- bl main
-#endif
-
-#else /* BOOTLOADER */
-
- /* Set up stack for IRQ mode */
- msr cpsr_c, #0xd2
- ldr sp, =irq_stack
- /* Set up stack for FIQ mode */
- msr cpsr_c, #0xd1
- ldr sp, =fiq_stack
-#ifdef CPU_PP
- /* We'll load the banked FIQ mode registers with useful values here.
- These values will be used in the FIQ handler in pcm_playback.c */
-#if CONFIG_CPU == PP5002
- ldr r12, =0xc0002500 /* PP5002 IISCONFIG */
-#else
- ldr r12, =0x70002800 /* PP502x IISCONFIG */
-#endif
- ldr r11, =p
-#endif
- /* Let abort and undefined modes use IRQ stack */
- msr cpsr_c, #0xd7
- ldr sp, =irq_stack
- msr cpsr_c, #0xdb
- ldr sp, =irq_stack
- /* Switch to supervisor mode */
- msr cpsr_c, #0xd3
- ldr sp, =stackend
- bl main
- /* main() should never return */
-
-#ifdef CPU_PP
-cop_init:
- ldr sp, =cop_stackend
- mov r3, sp
- ldr r2, =cop_stackbegin
- ldr r4, =0xdeadbeef
-2:
- cmp r3, r2
- strhi r4, [r2], #4
- bhi 2b
-
- ldr sp, =cop_stackend
- bl cop_main
-#endif /* PP specific */
-
-/* Exception handlers. Will be copied to address 0 after memory remapping */
- .section .vectors,"aw"
- ldr pc, [pc, #24]
- ldr pc, [pc, #24]
- ldr pc, [pc, #24]
- ldr pc, [pc, #24]
- ldr pc, [pc, #24]
- ldr pc, [pc, #24]
- ldr pc, [pc, #24]
- ldr pc, [pc, #24]
-
- /* Exception vectors */
- .global vectors
-vectors:
- .word start
- .word undef_instr_handler
- .word software_int_handler
- .word prefetch_abort_handler
- .word data_abort_handler
- .word reserved_handler
- .word irq_handler
- .word fiq_handler
-
- .text
-
-#ifndef STUB
- .global irq
- .global fiq
- .global UIE
-#endif
-
-/* All illegal exceptions call into UIE with exception address as first
- parameter. This is calculated differently depending on which exception
- we're in. Second parameter is exception number, used for a string lookup
- in UIE.
- */
-undef_instr_handler:
- mov r0, lr
- mov r1, #0
- b UIE
-
-/* We run supervisor mode most of the time, and should never see a software
- exception being thrown. Perhaps make it illegal and call UIE?
- */
-software_int_handler:
-reserved_handler:
- movs pc, lr
-
-prefetch_abort_handler:
- sub r0, lr, #4
- mov r1, #1
- b UIE
-
-fiq_handler:
- @ Branch straight to FIQ handler in pcm_playback.c. This also handles the
- @ the correct return sequence.
- ldr pc, =fiq
-
-data_abort_handler:
- sub r0, lr, #8
- mov r1, #2
- b UIE
-
-irq_handler:
-#ifndef STUB
- stmfd sp!, {r0-r3, r12, lr}
- bl irq
- ldmfd sp!, {r0-r3, r12, lr}
-#endif
- subs pc, lr, #4
-
-#ifdef STUB
-UIE:
- b UIE
-#endif
-
-/* 256 words of IRQ stack */
- .space 256*4
-irq_stack:
-
-/* 256 words of FIQ stack */
- .space 256*4
-fiq_stack:
-
-#endif /* BOOTLOADER */
-
-#elif CONFIG_CPU == TCC730
+#if CONFIG_CPU == TCC730
/* Platform: Gmini 120/SP */
;; disable all interrupts
- clrsr fe
+ clrsr fe
clrsr ie
clrsr te
ld a14, #0x3F0000
@@ -531,431 +120,4 @@ irq_handler:
pop r3, r2
pop r1, r0
ret_irq
-
-#elif defined(CPU_COLDFIRE)
- move.w #0x2700,%sr
-
- move.l #vectors,%d0
- movec.l %d0,%vbr
-
- move.l #MBAR+1,%d0
- movec.l %d0,%mbar
-
- move.l #MBAR2+1,%d0
- movec.l %d0,%mbar2
-
- lea MBAR,%a0
- lea MBAR2,%a1
-
- clr.l (0x180,%a1) /* PLLCR = 0 */
-
- /* 64K DMA-capable SRAM at 0x10000000
- DMA is enabled and has priority in both banks
- All types of accesses are allowed
- (We might want to restrict that to save power) */
- move.l #0x10000e01,%d0
- movec.l %d0,%rambar1
-
- /* 32K Non-DMA SRAM at 0x10010000
- All types of accesses are allowed
- (We might want to restrict that to save power) */
- move.l #0x10010001,%d0
- movec.l %d0,%rambar0
-
- /* Chip select 0 - Flash ROM */
- moveq.l #0x00,%d0 /* CSAR0 - Base = 0x00000000 */
- move.l %d0,(0x080,%a0)
- move.l #FLASH_SIZE-0x10000+1,%d0 /* CSMR0 - All access */
- move.l %d0,(0x084,%a0)
- move.l #0x00000180,%d0 /* CSCR0 - no wait states, 16 bits, no bursts */
- move.l %d0,(0x088,%a0)
-
- /* Chip select 1 - LCD controller */
- move.l #0xf0000000,%d0 /* CSAR1 - Base = 0xf0000000 */
- move.l %d0,(0x08c,%a0)
- moveq.l #0x1,%d0 /* CSMR1 - 64K */
- move.l %d0,(0x090,%a0)
- move.l #0x00000180,%d0 /* CSCR1 - no wait states, 16 bits, no bursts */
- move.l %d0,(0x094,%a0)
-
- /* Chip select 2 - ATA controller */
- move.l #0x20000000,%d0 /* CSAR2 - Base = 0x20000000 */
- move.l %d0,(0x098,%a0)
- move.l #0x000f0001,%d0 /* CSMR2 - 64K, Only data access */
- move.l %d0,(0x09c,%a0)
- move.l #0x00000080,%d0 /* CSCR2 - no wait states, 16 bits, no bursts */
- move.l %d0,(0x0a0,%a0) /* NOTE: I'm not sure about the wait states.
- We have to be careful with the access times,
- since IORDY isn't connected to the HDD. */
-
-#if CONFIG_USBOTG == USBOTG_ISP1362
- /* Chip select 3 - USBOTG controller */
- move.l #0xc0000000,%d0 /* CSAR3 - Base = 0xc0000000 */
- move.l %d0,(0x0a4,%a0)
- moveq.l #0x1,%d0 /* CSMR3 - 64K */
- move.l %d0,(0x0a8,%a0)
- move.l #0x00000180,%d0 /* CSCR3 - no wait states, 16 bits, no bursts */
- move.l %d0,(0x0ac,%a0)
-#endif
-
-#ifdef BOOTLOADER
- /* Check if original firmware is still present */
- lea 0x00001000,%a2
- move.l (%a2),%d0
- move.l #0xfbfbfbf1,%d1
- cmp.l %d0,%d1
- beq.b .ignorecookie
-
- /* The cookie is not reset. This must mean that the boot loader
- has crashed. Let's start the original firmware immediately. */
- lea 0x10017ffc,%a2
- move.l (%a2),%d0
- move.l #0xc0015a17,%d1
- cmp.l %d0,%d1
- bne.b .nocookie
- /* Clear the cookie again */
- clr.l (%a2)
- jmp 8
-
-.nocookie:
- /* Set the cookie */
- move.l %d1,(%a2)
-.ignorecookie:
-
- /* Set up the DRAM controller. The refresh is based on the 11.2896MHz
- clock (5.6448MHz bus frequency). We haven't yet started the PLL */
-#if MEM < 32
- move.w #0x8004,%d0 /* DCR - Synchronous, 80 cycle refresh */
-#else
- move.w #0x8001,%d0 /* DCR - Synchronous, 32 cycle refresh */
-#endif
- move.w %d0,(0x100,%a0)
-
- /* Note on 32Mbyte models:
- We place the SDRAM on an 0x1000000 (16M) offset because
- the 5249 BGA chip has a fault which disables the use of A24. The
- suggested workaround by FreeScale is to offset the base address by
- half the DRAM size and increase the mask to the double.
- In our case this means that we set the base address 16M ahead and
- use a 64M mask.
- */
-#if MEM < 32
- move.l #0x31002324,%d0 /* DACR0 - Base 0x31000000, Banks on 21 and up,
- CAS latency 1, Page mode, No refresh yet */
- move.l %d0,(0x108,%a0)
- move.l #0x00fc0001,%d0 /* Size: 16M */
- move.l %d0,(0x10c,%a0) /* DMR0 - 32Mb */
-#else
- move.l #0x31002524,%d0 /* DACR0 - Base 0x31000000, Banks on 23 and up,
- CAS latency 1, Page mode, No refresh yet */
- move.l %d0,(0x108,%a0)
- move.l #0x03fc0001,%d0 /* Size: 64M because of workaround above */
- move.l %d0,(0x10c,%a0) /* DMR0 - 32Mb */
-#endif
-
- /* Precharge */
- moveq.l #8,%d0
- or.l %d0,(0x108,%a0) /* DACR0[IP] = 1, next access will issue a
- Precharge command */
- move.l #0xabcd1234,%d0
- move.l %d0,0x31000000 /* Issue precharge command */
-
- move.l #0x8000,%d0
- or.l %d0,(0x108,%a0) /* Enable refresh */
-
- /* Let it refresh */
- move.l #500,%d0
-.delayloop:
- subq.l #1,%d0
- bne.b .delayloop
-
- /* Mode Register init */
- moveq.l #0x40,%d0 /* DACR0[IMRS] = 1, next access will set the
- Mode Register */
- or.l %d0,(0x108,%a0)
-
- move.l #0xabcd1234,%d0
- move.l %d0,0x31000800 /* A12=1 means CASL=1 (a0 is not connected) */
-
- /* DACR0[IMRS] gets deactivated by the SDRAM controller */
-#endif /* BOOTLOADER */
-
- /* Invalicate cache */
- move.l #0x01000000,%d0
- movec.l %d0,%cacr
-
- /* Enable cache, default=non-cacheable,no buffered writes */
- move.l #0x80000000,%d0
- movec.l %d0,%cacr
-
- /* Cache enabled in SDRAM only, buffered writes enabled */
- move.l #0x3103c020,%d0
- movec.l %d0,%acr0
- moveq.l #0,%d0
- movec.l %d0,%acr1
-
-#ifndef BOOTLOADER
- /* zero out .ibss */
- lea _iedata,%a2
- lea _iend,%a4
- bra.b .iedatastart
-.iedataloop:
- clr.l (%a2)+
-.iedatastart:
- cmp.l %a2,%a4
- bhi.b .iedataloop
-
- /* copy the .iram section */
- lea _iramcopy,%a2
- lea _iramstart,%a3
- lea _iramend,%a4
- bra.b .iramstart
-.iramloop:
- move.l (%a2)+,(%a3)+
-.iramstart:
- cmp.l %a3,%a4
- bhi.b .iramloop
-#endif /* !BOOTLOADER */
-
-#ifdef IRIVER_H300_SERIES
- /* Set KEEP_ACT before doing the lengthy copy and zero-fill operations */
- move.l #0x00080000,%d0
- or.l %d0,(0xb4,%a1)
- or.l %d0,(0xb8,%a1)
- or.l %d0,(0xbc,%a1)
-#endif
-
- /* zero out bss */
- lea _edata,%a2
- lea _end,%a4
- bra.b .edatastart
-.edataloop:
- clr.l (%a2)+
-.edatastart:
- cmp.l %a2,%a4
- bhi.b .edataloop
-
- /* copy the .data section */
- lea _datacopy,%a2
- lea _datastart,%a3
- cmp.l %a2,%a3
- beq.b .nodatacopy /* Don't copy if src and dest are equal */
- lea _dataend,%a4
- bra.b .datastart
-.dataloop:
- move.l (%a2)+,(%a3)+
-.datastart:
- cmp.l %a3,%a4
- bhi.b .dataloop
-.nodatacopy:
-
- /* Munge the main stack */
- lea stackbegin,%a2
- lea stackend,%a4
- move.l %a4,%sp
- move.l #0xdeadbeef,%d0
-.mungeloop:
- move.l %d0,(%a2)+
- cmp.l %a2,%a4
- bhi.b .mungeloop
-
- jsr main
-.hoo:
- bra.b .hoo
-
- .section .resetvectors
-vectors:
- .long stackend
- .long start
-#else
- /* Platform: Archos Jukebox */
-
- mov.l .vbr_k,r1
-#ifdef DEBUG
- /* If we have built our code to be loaded via the standalone GDB
- * stub, we will have out VBR at some other location than 0x9000000.
- * We must copy the trap vectors for the GDB stub to our vector table. */
- mov.l .orig_vbr_k,r2
-
- /* Move the invalid instruction vector (4) */
- mov #4,r0
- shll2 r0
- mov.l @(r0,r2),r3
- mov.l r3,@(r0,r1)
-
- /* Move the invalid slot vector (6) */
- mov #6,r0
- shll2 r0
- mov.l @(r0,r2),r3
- mov.l r3,@(r0,r1)
-
- /* Move the bus error vector (9) */
- mov #9,r0
- shll2 r0
- mov.l @(r0,r2),r3
- mov.l r3,@(r0,r1)
-
- /* Move the DMA bus error vector (10) */
- mov #10,r0
- shll2 r0
- mov.l @(r0,r2),r3
- mov.l r3,@(r0,r1)
-
- /* Move the NMI vector as well (11) */
- mov #11,r0
- shll2 r0
- mov.l @(r0,r2),r3
- mov.l r3,@(r0,r1)
-
- /* Move the UserBreak vector as well (12) */
- mov #12,r0
- shll2 r0
- mov.l @(r0,r2),r3
- mov.l r3,@(r0,r1)
-
- /* Move the breakpoint trap vector (32) */
- mov #32,r0
- shll2 r0
- mov.l @(r0,r2),r3
- mov.l r3,@(r0,r1)
-
- /* Move the IO trap vector (33) */
- mov #33,r0
- shll2 r0
- mov.l @(r0,r2),r3
- mov.l r3,@(r0,r1)
-
- /* Move the serial Rx interrupt vector (105) */
- mov #105,r0
- shll2 r0
- mov.l @(r0,r2),r3
- mov.l r3,@(r0,r1)
-
- /* Move the single step trap vector (127) */
- mov #127,r0
- shll2 r0
- mov.l @(r0,r2),r3
- mov.l r3,@(r0,r1)
-#endif /* DEBUG */
- ldc r1,vbr
-
- mov #0,r0
- ldc r0,gbr
-
- /* zero out .ibss */
- mov.l .iedata_k,r0
- mov.l .iend_k,r1
- bra .iedatastart
- mov #0,r2
-.iedataloop: /* backwards is faster and shorter */
- mov.l r2,@-r1
-.iedatastart:
- cmp/hi r0,r1
- bt .iedataloop
-
- /* copy the .iram section */
- mov.l .iramcopy_k,r0
- mov.l .iram_k,r1
- mov.l .iramend_k,r2
- /* Note: We cannot put a PC relative load into the delay slot of a 'bra'
- instruction (the offset would be wrong), but there is nothing else to
- do before the loop, so the delay slot would be 'nop'. The cmp / bf
- sequence is the same length, but more efficient. */
- cmp/hi r1,r2
- bf .noiramcopy
-.iramloop:
- mov.l @r0+,r3
- mov.l r3,@r1
- add #4,r1
- cmp/hi r1,r2
- bt .iramloop
-.noiramcopy:
-
- /* zero out bss */
- mov.l .edata_k,r0
- mov.l .end_k,r1
- bra .edatastart
- mov #0,r2
-.edataloop: /* backwards is faster and shorter */
- mov.l r2,@-r1
-.edatastart:
- cmp/hi r0,r1
- bt .edataloop
-
- /* copy the .data section, for rombased execution */
- mov.l .datacopy_k,r0
- mov.l .data_k,r1
- cmp/eq r0,r1
- bt .nodatacopy /* Don't copy if src and dest are equal */
- mov.l .dataend_k,r2
- cmp/hi r1,r2
- bf .nodatacopy
-.dataloop:
- mov.l @r0+,r3
- mov.l r3,@r1
- add #4,r1
- cmp/hi r1,r2
- bt .dataloop
-.nodatacopy:
-
- /* Munge the main thread stack */
- mov.l .stackbegin_k,r0
- mov.l .stackend_k,r1
- mov r1,r15
- mov.l .deadbeef_k,r2
-.mungeloop: /* backwards is faster and shorter */
- mov.l r2,@-r1
- cmp/hi r0,r1
- bt .mungeloop
-
- /* call the mainline */
- mov.l .main_k,r0
- jsr @r0
- nop
-.hoo:
- bra .hoo
- nop
-
- .align 2
-.vbr_k:
- .long vectors
-#ifdef DEBUG
-.orig_vbr_k:
- .long 0x09000000
-#endif
-.iedata_k:
- .long _iedata
-.iend_k:
- .long _iend
-.iramcopy_k:
- .long _iramcopy
-.iram_k:
- .long _iramstart
-.iramend_k:
- .long _iramend
-.edata_k:
- .long _edata
-.end_k:
- .long _end
-.datacopy_k:
- .long _datacopy
-.data_k:
- .long _datastart
-.dataend_k:
- .long _dataend
-.stackbegin_k:
- .long _stackbegin
-.stackend_k:
- .long _stackend
-.deadbeef_k:
- .long 0xdeadbeef
-.main_k:
- .long _main
-
- .section .resetvectors
-vectors:
- .long start
- .long _stackend
- .long start
- .long _stackend
#endif