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

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
      */