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authorKarl Kurbjun <kkurbjun@gmail.com>2008-09-26 02:54:29 +0000
committerKarl Kurbjun <kkurbjun@gmail.com>2008-09-26 02:54:29 +0000
commit143b8f1c305cf740b2598fafa6ccc517b8915f1a (patch)
treed616670d991d4d07a7141eeee923f9ff61a87a2a /firmware/target/arm
parent28643263b7f1b26c79d299e25553a40b64b55a23 (diff)
downloadrockbox-143b8f1c305cf740b2598fafa6ccc517b8915f1a.tar.gz
rockbox-143b8f1c305cf740b2598fafa6ccc517b8915f1a.zip
More Gigabeat F flash work. This sets the bootloader up for dual boot functionality and allows the player to shutdown cleanly (with the help of the OF). This does not effect the normal build or non-flash bootloader.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@18650 a1c6a512-1295-4272-9138-f99709370657
Diffstat (limited to 'firmware/target/arm')
-rw-r--r--firmware/target/arm/s3c2440/crt0.S120
1 files changed, 65 insertions, 55 deletions
diff --git a/firmware/target/arm/s3c2440/crt0.S b/firmware/target/arm/s3c2440/crt0.S
index e916cafe40..ff5eafd042 100644
--- a/firmware/target/arm/s3c2440/crt0.S
+++ b/firmware/target/arm/s3c2440/crt0.S
@@ -9,7 +9,8 @@
*
* Copyright (C) 2008 by Karl Kurbjun
*
- * Arm bootloader and startup code based on startup.s from the iPodLinux loader
+ * Arm 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>
*
@@ -41,12 +42,12 @@ vectors:
b fiq_handler
/* This branch is used to make sure that we know where the shutdown routine
- * is located in flash (0x04000020)
+ * is located in flash (0x040A0020)
*/
b rom_shutdown
/* Add some strings to detect the bootloader in flash and give it a version
- * number. (0x04000024, 0x04000028)
+ * number. (0x040A0028, 0x040A002C)
*/
.string "ROCKBOX"
.word 0x0001
@@ -80,10 +81,56 @@ word_copy:
.section .init.text,"ax",%progbits
.code 32
-.align 0x04 /* Align */
+.align 0x04
.global start
start:
- msr cpsr, #0xd3 /* enter supervisor mode, disable IRQ */
+
+ /* Get the execute address; R0 is used to store the address and it should
+ * not be written to till the rest of the execution checks are done below.
+ * This is done first thing since we have to check if the code was started
+ * with the old rockbox bootloader that offset the image by 100 bytes.
+ */
+ ldr r0, =0xffffff00
+ and r0, pc, r0
+
+ /************************** DO NOT WRITE TO R0 ***************************/
+
+ /* Check if the code is running from flash. If not skip all these checks */
+ cmp r0, #0xA0000
+ bne poweron
+
+ /* Set GPG up to read power and menu status */
+ ldr r2, =0x56000050
+ ldr r1, [r2, #0x18]
+ orr r1, r1, #0x03
+ str r1, [r2, #0x18]
+
+ /* Check if menu is held down */
+ ldr r1, [r2, #0x14]
+ ands r3, r1, #0x02
+ bne bootOF
+
+ /* Check if power is held down */
+ ands r3, r1, #0x01
+ bne poweron
+
+ /* Set GPF up to read charger connection if power is not held down */
+ ldr r1, [r2, #0x08]
+ orr r1, r1, #0x10
+ str r1, [r2, #0x08]
+
+ /* Check if charger is connected */
+ ldr r1, [r2, #0x04]
+ ands r1, r1, #0x10
+ beq poweron
+
+bootOF:
+ /* power is not down || menu is held || the charger is not connected */
+ mov pc, #0x70
+
+poweron:
+ /* enter supervisor mode, disable IRQ */
+ msr cpsr, #0xd3
/* Disable the watchdog */
ldr r2, =0x00000000
@@ -100,17 +147,11 @@ start:
str r2, [r1, #0x1C]
/* Check if loaded by the old bootloader or by the OF. This copy routine
- * cannot run/copy properly until the memory has been initialized, so the copy
- * routine later is still necessary. The old bootloader/OF will initialize the
- * memory.
- * Be careful with code size above this as well since this routine has to start
- * before 0x100 for it to work right.
+ * cannot run/copy properly until the memory has been initialized, so the
+ * copy routine later is still necessary. The old bootloader/OF will
+ * initialize the memory.
*/
- /* Get the execute address (cannot be past 0x100 for this to work */
- ldr r0, =0xffffff00
- and r0, pc, r0
-
/* Calculate the length of the code needed to run/copy */
ldr r1, = _vectorstart
ldr r2, = _initdata_end
@@ -124,19 +165,21 @@ start:
/* There's enough space, skip copying */
bgt skipreset
- /* Is this code running from 0x0? If so skip copy. */
- cmplt r0, #0
+ /* Is this code running from 0xA0000? If so skip copy. */
+ cmplt r0, #0xA0000
beq skipreset
+
+ /****************************** OK TO USE R0 *****************************/
- /* There's not enough space to copy without overwriting, copy to safe spot
- * and reset
+ /* There's not enough space to copy without overwriting, copy to safe
+ * spot and reset
*/
mov r1, #0x31000000 /* copy location */
bl word_copy
mov pc, #0x31000000
- skipreset:
+skipreset:
/* Initial Clock Setup */
/* set Bus to Asynchronous mode (full speed) */
@@ -319,39 +362,6 @@ start:
ldr r2, =0x00FFFFFF
str r2, [r1]
-#if 0
- /* GPACON */
- mov r1, #0x56000000
- ldr r2, =0x01FFFCFF /* 0x01FFFCFF */
- str r2, [r1]
-
- /* GPADAT */
- ldr r2, =0x01FFFEFF
- str r2, [r1, #0x04]
-
- /* MRSRB6 */
- mov r1, #0x48000000
- mov r2, #0x00000000
- str r2, [r1, #0x2C]
-
- /* GPADAT */
- mov r1, #0x56000000
- ldr r2, =0x01FFFFFF
- str r2, [r1, #0x04]
-
- /* MRSRB6 */
- mov r1, #0x48000000
- mov r2, #0x00000030
- str r2, [r1, #0x2C]
-
- /* GPACON */
- mov r1, #0x56000000
- mov r2, #0x01FFFFFF
- str r2, [r1]
-
- /* End of the unknown */
-#endif
-
/* The builds have two potential load addresses, one being from flash,
* and the other from some "unknown" location right now the assumption
* is that the code is not at 0x3000000.
@@ -373,7 +383,7 @@ start:
ldr r1, =donecopy
ldr r2, =0x30000000
add r1, r1, r2
- mov pc, r1 /* The code is located where we want it-jump*/
+ mov pc, r1 /* The code is located where we want it so jump */
donecopy:
@@ -444,7 +454,7 @@ stackmunge:
/* Start the main function */
ldr pc, =main
- /* Should never get here, but let's restart in case (also needed when
+ /* Should never get here, but let's restart in case (also needed for
* linking)
*/
b vectors
@@ -600,7 +610,7 @@ rom_shutdown:
ldr r2, [lr]
// str r2, [r11,#-0x28]
ldr r3, [r0]
- Orr r3, r3, #0x00400000
+ orr r3, r3, #0x00C00000
/* REFRESH
* [22] TREFMD - SDRAM Refresh Mode
*/