From 86d319551864035038ea0b9355b6fa1815398bfd Mon Sep 17 00:00:00 2001
From: marcansoft <marcansoft@ef4ab9da-24cd-11de-8aaa-f3a34680c41f>
Date: Fri, 26 Feb 2010 15:14:47 +0000
Subject: [PATCH 1/1] Bootloader cleanup (UNTESTED!)
- Clean up bootloader asm
- Remove fromflash.c - it's not worth doing in C, do it in ASM
- Clean up linker script
- Force use of symbol inside bootphase2 (otherwise linker
garbage-collects it)
- Link bootloader with gcc instead of ld
---
bootrom/Makefile | 4 +-
bootrom/flash-reset.s | 80 +++++++++++++++++++-------------------
bootrom/fromflash.c | 21 ----------
bootrom/ldscript-flash | 87 +++++++++++++++++++-----------------------
bootrom/ram-reset.s | 15 ++++----
5 files changed, 90 insertions(+), 117 deletions(-)
delete mode 100644 bootrom/fromflash.c
diff --git a/bootrom/Makefile b/bootrom/Makefile
index a3374b0c..0f661a8f 100644
--- a/bootrom/Makefile
+++ b/bootrom/Makefile
@@ -7,7 +7,7 @@
#-----------------------------------------------------------------------------
# DO NOT use thumb mode in the phase 1 bootloader since that generates a section with glue code
-ARMSRC = fromflash.c
+ARMSRC =
THUMBSRC = usb.c bootrom.c
ASMSRC = ram-reset.s flash-reset.s
@@ -27,7 +27,7 @@ include ../common/Makefile.common
all: $(OBJDIR)/bootrom.s19
$(OBJDIR)/bootrom.elf: $(VERSIONOBJ) $(ASMOBJ) $(ARMOBJ) $(THUMBOBJ)
- $(LD) -g -Tldscript-flash --oformat elf32-littlearm -Map=$(patsubst %.elf,%.map,$@) -o $@ $^
+ $(CC) $(LDFLAGS) -Wl,-T,ldscript-flash,-Map,$(patsubst %.elf,%.map,$@) -o $@ $^ $(LIBS)
clean:
$(DELETE) $(OBJDIR)$(PATHSEP)*.o
diff --git a/bootrom/flash-reset.s b/bootrom/flash-reset.s
index 8b58636f..54ee15b0 100644
--- a/bootrom/flash-reset.s
+++ b/bootrom/flash-reset.s
@@ -6,46 +6,48 @@
@ Reset vector for running from FLASH
@-----------------------------------------------------------------------------
-.extern CopyBootToRAM
-
.section .startup,"ax"
- .code 32
- .align 0
+
+.arm
.global flashstart
flashstart:
- b Reset
- b UndefinedInstruction
- b SoftwareInterrupt
- b PrefetchAbort
- b DataAbort
- b Reserved
- b Irq
- b Fiq
-
-Reset:
- ldr sp, .stack_end @ initialize stack pointer to top of RAM
- bl CopyBootToRAM @ copy bootloader to RAM (in case the
- @ user re-flashes the bootloader)
- ldr r3, .bootphase2_start @ start address of RAM bootloader
- bx r3 @ jump to it
-
- .stack_end:
- .word _stack_end
- .bootphase2_start:
- .word __bootphase2_start__
-
-Fiq:
- b Fiq
-UndefinedInstruction:
- b UndefinedInstruction
-SoftwareInterrupt:
- b SoftwareInterrupt
-PrefetchAbort:
- b PrefetchAbort
-DataAbort:
- b DataAbort
-Reserved:
- b Reserved
-Irq:
- b Irq
+ b reset
+ b undefined_instruction
+ b software_interrupt
+ b prefetch_abort
+ b data_abort
+ b . @reserved
+ b irq
+ b fiq
+
+reset:
+ ldr sp, =_stack_end @ initialize stack pointer to top of RAM
+
+ @ copy bootloader to RAM (in case the user re-flashes the bootloader)
+ ldr r0, =__bootphase2_src_start__
+ ldr r1, =__bootphase2_start__
+ ldr r2, =__bootphase2_end__
+1:
+ ldr r3, [r0], #4
+ str r3, [r1], #4
+ cmp r1, r2
+ blo 1b
+
+ ldr r3, =ram_start @ start address of RAM bootloader
+ bx r3 @ jump to it
+
+ .ltorg
+
+undefined_instruction:
+ b .
+software_interrupt:
+ b .
+prefetch_abort:
+ b .
+data_abort:
+ b .
+irq:
+ b .
+fiq:
+ b .
diff --git a/bootrom/fromflash.c b/bootrom/fromflash.c
deleted file mode 100644
index 81501fd0..00000000
--- a/bootrom/fromflash.c
+++ /dev/null
@@ -1,21 +0,0 @@
-//-----------------------------------------------------------------------------
-// This code is licensed to you under the terms of the GNU GPL, version 2 or,
-// at your option, any later version. See the LICENSE.txt file for the text of
-// the license.
-//-----------------------------------------------------------------------------
-// Helper function for launching the bootloader from FLASH
-//-----------------------------------------------------------------------------
-
-#include <proxmark3.h>
-
-extern char __bootphase2_src_start__, __bootphase2_start__, __bootphase2_end__;
-void __attribute__((section(".bootphase1"))) CopyBootToRAM(void)
-{
- int i;
-
- volatile uint32_t *s = (volatile uint32_t *)&__bootphase2_src_start__;
- volatile uint32_t *d = (volatile uint32_t *)&__bootphase2_start__;
- unsigned int l = (int)&__bootphase2_end__ - (int)&__bootphase2_start__;
-
- for(i = 0; i < l/sizeof(uint32_t); i++) *d++ = *s++;
-}
diff --git a/bootrom/ldscript-flash b/bootrom/ldscript-flash
index ba6384c5..5936a8fe 100644
--- a/bootrom/ldscript-flash
+++ b/bootrom/ldscript-flash
@@ -13,51 +13,44 @@ INCLUDE ../common/ldscript.common
ENTRY(flashstart)
SECTIONS
{
- . = 0;
-
- .bootphase1 : {
- *(.startup)
- *(.bootphase1)
-
- /* It seems to be impossible to flush align a section at the
- end of a memory segment. Instead, we'll put the version_information
- wherever the linker wants it, and then put a pointer to the start
- of the version information at the end of the section.
- -- Henryk Plötz <henryk@ploetzli.ch> 2009-08-28 */
-
- _version_information_start = ABSOLUTE(.);
- *(.version_information);
-
- /* Why doesn't this work even though _bootphase1_version_pointer = 0x1001fc?
- . = _bootphase1_version_pointer - ORIGIN(bootphase1); */
- /* This works, apparently it fools the linker into accepting an absolute address */
- . = _bootphase1_version_pointer - ORIGIN(bootphase1) + ORIGIN(bootphase1);
- LONG(_version_information_start)
- } >bootphase1
-
- __bootphase2_src_start__ = ORIGIN(bootphase2);
- .bootphase2 : {
- __bootphase2_start__ = .;
- *(.startphase2)
- *(.text)
- *(.eh_frame)
- *(.glue_7)
- *(.glue_7t)
- *(.rodata)
- *(.data)
- . = ALIGN( 32 / 8 );
- __bootphase2_end__ = .;
- } >ram AT>bootphase2
-
- .bss : {
- __bss_start__ = .;
- *(.bss)
- } >ram
-
- . = ALIGN( 32 / 8 );
- __bss_end__ = .;
-
- .commonarea (NOLOAD) : {
- *(.commonarea)
- } >commonarea
+ .bootphase1 : {
+ *(.startup)
+
+ . = ALIGN(4);
+ _version_information_start = .;
+ *(.version_information);
+
+ . = LENGTH(bootphase1) - 0x4;
+ LONG(_version_information_start);
+ } >bootphase1
+
+ .bootphase2 : {
+ *(.startphase2)
+ *(.text)
+ *(.text.*)
+ *(.eh_frame)
+ *(.glue_7)
+ *(.glue_7t)
+ *(.rodata)
+ *(.rodata.*)
+ *(.data)
+ *(.data.*)
+ . = ALIGN(4);
+ } >ram AT>bootphase2
+
+ __bootphase2_src_start__ = LOADADDR(.bootphase2);
+ __bootphase2_start__ = ADDR(.bootphase2);
+ __bootphase2_end__ = __bootphase2_start__ + SIZEOF(.bootphase2);
+
+ .bss : {
+ __bss_start__ = .;
+ *(.bss)
+ *(.bss.*)
+ . = ALIGN(4);
+ __bss_end__ = .;
+ } >ram
+
+ .commonarea (NOLOAD) : {
+ *(.commonarea)
+ } >commonarea
}
diff --git a/bootrom/ram-reset.s b/bootrom/ram-reset.s
index 34c950f6..ade70d8c 100644
--- a/bootrom/ram-reset.s
+++ b/bootrom/ram-reset.s
@@ -9,13 +9,12 @@
.extern BootROM
.section .startphase2,"ax"
- .code 32
- .align 0
-.global ramstart
-ramstart:
- ldr sp, .stack_end
- bl BootROM
+.arm
- .stack_end:
- .word _stack_end
+.global ram_start
+ram_start:
+ ldr sp, =_stack_end
+ bl BootROM
+
+ .ltorg
--
2.39.5