Make the Nano2G bootloader actually function as a bootloader. The resulting bootloader-ipodnano2g.ipod file needs to be encrypted on a target using the crypt_firmware plugin to create bootloader-ipodnano2g.ipodx, which can then be written to the firmware partition using the ipodpatcher patch at FS#10609. Dual-booting doesn't work yet - only Rockbox can be run.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@23084 a1c6a512-1295-4272-9138-f99709370657

firmware/target/arm/s5l8700/boot.lds

@@ -9,14 +9,14 @@ OUTPUT_FORMAT(elf32-bigarm)
 OUTPUT_ARCH(arm)
 STARTUP(target/arm/s5l8700/crt0.o)
 
-/* DRAMORIG is in fact 0x08000000 but remapped to 0x0 */
 #define DRAMORIG 0x08000000
 #define DRAMSIZE (MEMORYSIZE * 0x100000)
 
-#define IRAMORIG 0x22000000
 #if CONFIG_CPU==S5L8701
+#define IRAMORIG 0x0
 #define IRAMSIZE 176K
 #else
+#define IRAMORIG 0x22000000
 #define IRAMSIZE 256K
 #endif
 
@@ -91,7 +91,11 @@ SECTIONS
      _fiqstackend = .;
   } > IRAM
 
-  .bss : {
+  /* The bss section is too large for IRAM - we just move it 12MB into the
+     DRAM */
+
+  . = DRAMORIG;
+  .bss . + (12*1024*1024): {
      _edata = .;
      *(.bss*);
      *(.ibss);
@@ -99,5 +103,5 @@ SECTIONS
      *(COMMON);
     . = ALIGN(0x4);
      _end = .;
-   } > IRAM
+  } > DRAM
 }

firmware/target/arm/s5l8700/crt0.S

@@ -27,7 +27,11 @@
     .global    _newstart
     /* Exception vectors */
 start:
+#if CONFIG_CPU==S5L8701 && defined(BOOTLOADER)
+    b newstart2
+#else
     b _newstart
+#endif
     ldr pc, =undef_instr_handler
     ldr pc, =software_int_handler
     ldr pc, =prefetch_abort_handler
@@ -88,7 +92,22 @@ newstart2:
     orr r2, r2, #1
     bic r2, r2, #0x10000
     str r2, [r1] // remap iram to address 0x0
-#endif
+
+#ifdef BOOTLOADER
+    /* Relocate ourself to IRAM - we have been loaded to DRAM */
+    mov    r0, #0x08000000   /* source (DRAM) */
+    mov    r1, #0x00000000   /* dest (IRAM) */
+    ldr    r2, =_dataend
+1:
+    cmp    r2, r1
+    ldrhi  r3, [r0], #4
+    strhi  r3, [r1], #4
+    bhi    1b
+
+    ldr    pc, =start_loc    /* jump to the relocated start_loc:  */
+start_loc:
+#endif /* BOOTLOADER */
+#endif /* CONFIG_CPU==S5L8701 */
 
     ldr r1, =0x3c500000 // CLKCON
     ldr r0, =0x00800080

firmware/target/arm/s5l8700/ipodnano2g/ftl-target.h

@@ -25,6 +25,11 @@
 #include "config.h"
 #include "inttypes.h"
 
+#ifdef BOOTLOADER
+/* Bootloaders don't need write access */
+#define FTL_READONLY
+#endif
+
 uint32_t ftl_init(void);
 uint32_t ftl_read(uint32_t sector, uint32_t count, void* buffer);
 uint32_t ftl_write(uint32_t sector, uint32_t count, const void* buffer);