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| author | Michael Sevakis <jethead71@rockbox.org> | 2009-02-10 15:48:48 +0000 |
|---|---|---|
| committer | Michael Sevakis <jethead71@rockbox.org> | 2009-02-10 15:48:48 +0000 |
| commit | e46309fde381bd235935c0c0a79e40d681307c24 (patch) | |
| tree | 75f877e0fd26b5ef2cd0f6d2dc406dfb13bb87e6 | |
| parent | 609157a145eedae3506abe59378c74b713a399d6 (diff) | |
| download | rockbox-e46309fde381bd235935c0c0a79e40d681307c24.tar.gz rockbox-e46309fde381bd235935c0c0a79e40d681307c24.zip | |
Gigabeat S: Update some very stale comments about what's going on in the startup code.
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@19965 a1c6a512-1295-4272-9138-f99709370657
| -rw-r--r-- | firmware/target/arm/imx31/crt0.S | 18 |
1 files changed, 8 insertions, 10 deletions
diff --git a/firmware/target/arm/imx31/crt0.S b/firmware/target/arm/imx31/crt0.S index d51de7215a..7118c7572f 100644 --- a/firmware/target/arm/imx31/crt0.S +++ b/firmware/target/arm/imx31/crt0.S | |||
| @@ -43,21 +43,19 @@ start: | |||
| 43 | * | 43 | * |
| 44 | */ | 44 | */ |
| 45 | 45 | ||
| 46 | /* Initially this code is running at VA 0x8a000000 (PA 0x82000000). | 46 | /* Bootloader: |
| 47 | * The mapping stub is copied to IRAM (0x1fffc000) and jumps to the final | 47 | * Initially this code is running at VA 0x8a000000 (PA 0x82000000). |
| 48 | * VA remapping starting at 0x01f00000 because the 1MB section containing | 48 | * The mapping stub is copied to IRAM (0x1fffc000), sets up the MMU and |
| 49 | * the framebuffer at PA 0x81000000 is skipped in the remapping giving 63MB | 49 | * jumps into the final VA remapping starting at 0x02000000 (32MB). |
| 50 | * of contiguous RAM for the firmware. The TTB is placed at the end of said | ||
| 51 | * section. | ||
| 52 | * | 50 | * |
| 53 | * For now this will be done in bootloader, especially if usb will be needed | 51 | * Firmware: |
| 54 | * within the bootloader to load the main firmware file. Interrupts will be | 52 | * This code will be running from VA 0x00000000 (PA 0x80000000) and perform |
| 55 | * needed for this (whether they be swi or irq). | 53 | * similar steps to the bootloader code. |
| 56 | */ | 54 | */ |
| 57 | newstart: | 55 | newstart: |
| 58 | msr cpsr_c, #0xd3 /* enter supervisor mode, disable IRQ/FIQ */ | 56 | msr cpsr_c, #0xd3 /* enter supervisor mode, disable IRQ/FIQ */ |
| 59 | 57 | ||
| 60 | adr r2, remap_start /* Load PC-relative labels */ | 58 | adr r2, remap_start /* Load PC-relative labels (relocatable) */ |
| 61 | adr r3, remap_end | 59 | adr r3, remap_end |
| 62 | ldr r5, =TTB_BASE_ADDR /* TTB pointer */ | 60 | ldr r5, =TTB_BASE_ADDR /* TTB pointer */ |
| 63 | ldr r6, =IRAM_BASE_ADDR | 61 | ldr r6, =IRAM_BASE_ADDR |