iPod: Fix the bootloader so it can load and run the original Apple firmware again. The Rockbox firmware was doing too much to the hardware so we remove most of the initialisation.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@8301 a1c6a512-1295-4272-9138-f99709370657

bootloader/ipod.c

@@ -415,7 +415,16 @@ void* main(void)
             lcd_puts(0, line++, "Rockbox loaded.");
             lcd_update();
             memcpy((void*)DRAM_START,loadbuffer,rc);
-            return (void*)DRAM_START;
+
+            /* Transfer execution directly to Rockbox - we don't want
+               to run the rest of the bootloader startup code. */
+            asm volatile(
+                "mov   r0, #0x10000000    \n"
+                "mov   pc, r0             \n"
+            );
+
+            /* We don't get here, but keep the compiler happy. */
+            return (void*)0;
         }
     }
 

firmware/crt0.S

@@ -197,12 +197,13 @@ 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 0
-/* TODO: fix something for the COP to wake up to, until then let it sleep. */
 #if CONFIG_CPU==PP5002
     /* make sure COP is sleeping */
     ldr    r4, =0xcf004050
@@ -227,8 +228,7 @@ start_loc:
     @ldr    r4, =PP5020_COP_CTRL
     mov    r3, #0x0
     str    r3, [r4]
-#endif 
+#endif
-#endif 
     /* jump to start location */
     mov    pc, r0
 

firmware/drivers/power.c

@@ -262,8 +262,10 @@ void power_off(void)
 #if CONFIG_CPU == MCF5249
     and_l(~0x00080000, &GPIO1_OUT);
 #elif CONFIG_CPU == PP5020
+#ifndef BOOTLOADER
     /* We don't turn off the ipod, we put it in a deep sleep */
     pcf50605_standby_mode();
+#endif
 #elif defined(GMINI_ARCH)
     P1 &= ~1;
     P1CON &= ~1;

firmware/export/config-ipodcolor.h

@@ -27,7 +27,9 @@
 #define CONFIG_CODEC SWCODEC
 
 /* define this if you have a real-time clock */
+#ifndef BOOTLOADER
 #define CONFIG_RTC RTC_PCF50605
+#endif
 
 /* Define this if you have a software controlled poweroff */
 #define HAVE_SW_POWEROFF

firmware/export/config-ipodnano.h

@@ -27,7 +27,9 @@
 #define CONFIG_CODEC SWCODEC
 
 /* define this if you have a real-time clock */
+#ifndef BOOTLOADER
 #define CONFIG_RTC RTC_PCF50605
+#endif
 
 /* Define this if you have a software controlled poweroff */
 #define HAVE_SW_POWEROFF

firmware/export/config-ipodvideo.h

@@ -27,7 +27,9 @@
 #define CONFIG_CODEC SWCODEC
 
 /* define this if you have a real-time clock */
+#ifndef BOOTLOADER
 #define CONFIG_RTC RTC_PCF50605
+#endif
 
 /* Define this if you have a software controlled poweroff */
 #define HAVE_SW_POWEROFF

firmware/export/kernel.h

@@ -66,7 +66,13 @@ struct mutex
 };
 
 /* global tick variable */
+#if (CONFIG_CPU == PP5020) && defined(BOOTLOADER)
+/* We don't enable interrupts in the iPod bootloader, so we need to fake
+   the current_tick variable */
+#define current_tick ((*((volatile long*)0x60005010))/10000)
+#else
 extern long current_tick;
+#endif
 
 #ifdef SIMULATOR
 #define sleep(x) sim_sleep(x)

firmware/kernel.c

@@ -25,7 +25,9 @@
 #include "system.h"
 #include "panic.h"
 
+#if (CONFIG_CPU != PP5020) || !defined(BOOTLOADER)
 long current_tick = 0;
+#endif
 
 static void (*tick_funcs[MAX_NUM_TICK_TASKS])(void);
 
@@ -48,7 +50,7 @@ void kernel_init(void)
 
     num_queues = 0;
     memset(all_queues, 0, sizeof(all_queues));
-    
+
     tick_start(1000/HZ);
 }
 
@@ -319,6 +321,7 @@ void tick_start(unsigned int interval_in_ms)
 
 #define USECS_PER_INT 0x2710
 
+#ifndef BOOTLOADER
 void TIMER1(void)
 {
     int i;
@@ -336,9 +339,11 @@ void TIMER1(void)
     current_tick++;
     wake_up_thread();
 }
+#endif
 
 void tick_start(unsigned int interval_in_ms)
 {
+#ifndef BOOTLOADER
     /* TODO: use interval_in_ms to set timer periode */
     (void)interval_in_ms;
     PP5020_TIMER1 = 0x0;
@@ -347,6 +352,10 @@ void tick_start(unsigned int interval_in_ms)
     PP5020_TIMER1 = 0xc0000000 | USECS_PER_INT;
     /* unmask interrupt source */
     PP5020_CPU_INT_EN = PP5020_TIMER1_MASK;
+#else
+    /* We don't enable interrupts in the bootloader */
+    (void)interval_in_ms;
+#endif
 }
 
 #endif

firmware/system.c

@@ -1106,6 +1106,7 @@ int system_memory_guard(int newmode)
 }
 #elif CONFIG_CPU==PP5020
 
+#ifndef BOOTLOADER
 extern void TIMER1(void);
 extern void ipod_4g_button_int(void);
 
@@ -1116,6 +1117,7 @@ void irq(void)
     else if (PP5020_CPU_HI_INT_STAT & PP5020_I2C_MASK)
         ipod_4g_button_int();
 }
+#endif
 
 /* TODO: The following two function have been lifted straight from IPL, and
    hence have a lot of numeric addresses used straight. I'd like to use
@@ -1124,11 +1126,10 @@ void irq(void)
    to extend the funtions to do alternate cache configurations and/or 
    some other CPU frequency scaling. */
 
+#ifndef BOOTLOADER
 static void ipod_init_cache(void)
 {
-/* Initialising the cache in the iPod Video bootloader prevents
+/* Initialising the cache in the iPod bootloader prevents Rockbox from starting */
-   Rockbox from starting */
-#if !defined(BOOTLOADER) || !defined(APPLE_IPODVIDEO)
     unsigned i;
 
     /* cache init mode? */
@@ -1147,7 +1148,6 @@ static void ipod_init_cache(void)
 
     for (i = 0x10000000; i < 0x10002000; i += 16)
         inb(i);
-#endif
 }
     
 static void ipod_set_cpu_speed(void)
@@ -1163,9 +1163,11 @@ static void ipod_set_cpu_speed(void)
 
     outl((inl(0x60006020) & 0x0fffff0f) | 0x20000070, 0x60006020);
 }
+#endif
 
 void system_init(void)
 {
+#ifndef BOOTLOADER
     /* disable all irqs */
     outl(-1, 0x60001138);
     outl(-1, 0x60001128);
@@ -1176,6 +1178,7 @@ void system_init(void)
     outl(-1, 0x6000101c);
     ipod_set_cpu_speed();
     ipod_init_cache();
+#endif
 }
 
 void system_reboot(void)