From: hackbard <hackbard@staubsauger.localdomain>
Date: Thu, 20 Sep 2007 21:53:07 +0000 (+0200)
Subject: irq/fiq enabled, copy vectors if code resides in ram
X-Git-Url: https://hackdaworld.org/gitweb/?p=my-code%2Farm.git;a=commitdiff_plain;h=5289778b44c03bc85a970ab2ece27e1888d47558

irq/fiq enabled, copy vectors if code resides in ram
---

diff --git a/betty/startup.s b/betty/startup.s
index d393d32..18006aa 100644
--- a/betty/startup.s
+++ b/betty/startup.s
@@ -41,6 +41,8 @@
 .equ	fiq_disable,	0x40
 .equ	irq_disable,	0x80
 
+.equ	vic_vect_addr,	0xfffff030
+
 #
 # the startup code
 #
@@ -57,6 +59,8 @@
 	#  - that's the vectored address register
 	#  - the vic put in there the address of our service routine
 
+exception_vectors:
+
 	ldr pc, handler_reset
 	ldr pc, handler_undef_instruction
 	ldr pc, handler_soft_ir
@@ -64,6 +68,7 @@
 	ldr pc, handler_data_abort
 	nop
 	ldr pc, [pc, #-0xff0]
+	#ldr pc, handler_irq
 	ldr pc, handler_fiq
 
 handler_reset: .word handle_reset
@@ -71,6 +76,7 @@ handler_undef_instruction: .word interrupt_handler_undef_instruction
 handler_soft_ir: .word interrupt_handler_soft_ir
 handler_prefetch_abort: .word interrupt_handler_prefetch_abort
 handler_data_abort: .word interrupt_handler_data_abort
+handler_irq: .word vic_vect_addr
 handler_fiq: .word interrupt_handler_fiq
 
 	# reset handling goes here
@@ -108,6 +114,9 @@ handle_reset:
 	ldr r0, =stack_limit
 	mov sl, r0
 
+	# enable irq and fiq
+	msr cpsr_c, #mode_system
+
 	# copy data section (only if we are in flash <=> _etext != _data)
 
 	ldr r1, =_etext
@@ -115,7 +124,7 @@ handle_reset:
 	ldr r3, =_edata
 
 	cmp r1, r2
-	beq start_of_c_code
+	beq copy_exception_vectors
 
 copy_data_loop:
 
@@ -123,6 +132,18 @@ copy_data_loop:
 	ldrlo r0, [r1], #4
 	strlo r0, [r2], #4
 	blo copy_data_loop
+	b start_of_c_code
+
+	# copy exception vectors (only if we are in ram <=> _etext = _data)
+
+copy_exception_vectors:
+
+	mov r0, #sram_addr
+	ldr r1, =exception_vectors
+	ldmia r1!, {r2-r9}
+	stmia r0!, {r2-r9}
+	ldmia r1!, {r2-r8}
+	stmia r0!, {r2-r8}
 
 	# jump to c code