Fix comments and reg frame offsets

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@460 42af7a65-404d-4744-a932-0658087f49c3

3 files changed, 32 insertions, 33 deletions

diff --git a/nuttx/arch/z80/src/common/up_head.asm b/nuttx/arch/z80/src/common/up_head.asm
index dad74d4c3..36a145be7 100644
--- a/nuttx/arch/z80/src/common/up_head.asm
+++ b/nuttx/arch/z80/src/common/up_head.asm
@@ -42,15 +42,15 @@
 

 	; Register save area layout

 

-	XCPT_PC	==  0		; Offset to PC at time of interrupt

-	XCPT_AF	==  2		; Saved AF register

-	XCPT_HL	==  4		; Saved HL register

-	XCPT_SP	==  6		; Offset to SP at time of interrupt

-	XCPT_IY	==  8		; Saved IY register

-	XCPT_IX	== 10		; Saved IX register

-	XCPT_DE	== 12		; Saved DE register

-	XCPT_BC	== 14		; Saved BC register

-	XCPT_I 	== 16		; Saved I w/interrupt state in carry

+	XCPT_I 	==  0		; Offset 0: Saved I w/interrupt state in carry

+	XCPT_BC	==  2		; Offset 1: Saved BC register

+	XCPT_DE	==  4		; Offset 2: Saved DE register

+	XCPT_IX	==  6		; Offset 3: Saved IX register

+	XCPT_IY	==  8		; Offset 4: Saved IY register

+	XCPT_SP	== 10		; Offset 5: Offset to SP at time of interrupt

+	XCPT_HL	== 12		; Offset 6: Saved HL register

+	XCPT_AF	== 14		; Offset 7: Saved AF register

+	XCPT_PC	== 16		; Offset 8: Offset to PC at time of interrupt

 

 	; Default stack base (needs to be fixed)

 

@@ -99,7 +99,7 @@ forever:
 					; Offset 8: Return PC is already on the stack

 	push	af			; Offset 7: AF (retaining flags)

 	push	hl			; Offset 6: HL

-	ld	hl, #-(3*2)		;    HL is the value of the stack pointer before

+	ld	hl, #(3*2)		;    HL is the value of the stack pointer before

 	add	hl, sp			;    the interrupt occurred

 	push	hl			; Offset 5: Stack pointer

 	push	iy			; Offset 4: IY

@@ -111,11 +111,10 @@ forever:
 	push	af			; Offset 0: I with interrupt state in carry

 	di

 

-	 ; Call the interrupt decode logic

-					; SP points to the beggining of the reg structure

+	 ; Call the interrupt decode logic. SP points to the beggining of the reg structure

 	ld	hl, #0			; Argument is the beginning of the reg structure

-	add	hl, sp

-	push	hl

+	add	hl, sp			;

+	push	hl			;

 	call	_up_decodeirq		; Decode the IRQ

 

 	; Restore registers.  HL points to the beginning of the reg structure to restore

diff --git a/nuttx/arch/z80/src/common/up_restoreusercontext.asm b/nuttx/arch/z80/src/common/up_restoreusercontext.asm
index 86b497426..1840b260e 100644
--- a/nuttx/arch/z80/src/common/up_restoreusercontext.asm
+++ b/nuttx/arch/z80/src/common/up_restoreusercontext.asm
@@ -35,15 +35,15 @@
 

 	; Register save area layout

 

-	.globl	XCPT_I		; Saved I w/interrupt state in carry

-	.globl	XCPT_AF		; Saved AF register

-	.globl	XCPT_BC		; Saved BC register

-	.globl	XCPT_DE		; Saved DE register

-	.globl	XCPT_HL		; Saved HL register

-	.globl	XCPT_IX		; Saved IX register

-	.globl	XCPT_IY		; Saved IY register

-	.globl	XCPT_SP		; Offset to SP at time of interrupt

-	.globl	XCPT_PC		; Offset to PC at time of interrupt

+	.globl	XCPT_I		; Offset 0: Saved I w/interrupt state in carry

+	.globl	XCPT_BC		; Offset 1: Saved BC register

+	.globl	XCPT_DE		; Offset 2: Saved DE register

+	.globl	XCPT_IX		; Offset 3: Saved IX register

+	.globl	XCPT_IY		; Offset 4: Saved IY register

+	.globl	XCPT_SP		; Offset 5: Offset to SP at time of interrupt

+	.globl	XCPT_HL		; Offset 6: Saved HL register

+	.globl	XCPT_AF		; Offset 7: Saved AF register

+	.globl	XCPT_PC		; Offset 8: Offset to PC at time of interrupt

 

 ;**************************************************************************

 ; up_restoreusercontext

diff --git a/nuttx/arch/z80/src/common/up_saveusercontext.asm b/nuttx/arch/z80/src/common/up_saveusercontext.asm
index 707fdd515..b5c0dbb21 100644
--- a/nuttx/arch/z80/src/common/up_saveusercontext.asm
+++ b/nuttx/arch/z80/src/common/up_saveusercontext.asm
@@ -39,15 +39,15 @@
 
 	; Register save area layout
 
-	.globl	XCPT_I		; Saved I w/interrupt state in carry
-	.globl	XCPT_AF		; Saved AF register
-	.globl	XCPT_BC		; Saved BC register
-	.globl	XCPT_DE		; Saved DE register
-	.globl	XCPT_HL		; Saved HL register
-	.globl	XCPT_IX		; Saved IX register
-	.globl	XCPT_IY		; Saved IY register
-	.globl	XCPT_SP		; Offset to SP at time of interrupt
-	.globl	XCPT_PC		; Offset to PC at time of interrupt
+	.globl	XCPT_I		; Offset 0: Saved I w/interrupt state in carry
+	.globl	XCPT_BC		; Offset 1: Saved BC register
+	.globl	XCPT_DE		; Offset 2: Saved DE register
+	.globl	XCPT_IX		; Offset 3: Saved IX register
+	.globl	XCPT_IY		; Offset 4: Saved IY register
+	.globl	XCPT_SP		; Offset 5: Offset to SP at time of interrupt
+	.globl	XCPT_HL		; Offset 6: Saved HL register
+	.globl	XCPT_AF		; Offset 7: Saved AF register
+	.globl	XCPT_PC		; Offset 8: Offset to PC at time of interrupt
 
 	; Stack frame
 
@@ -56,7 +56,7 @@
 	FRAME_RET	==  4	; Location of return address on the stack
 	FRAME_REGS	==  6	; Location of reg save area on stack
 
-	SP_OFFSET	== -6
+	SP_OFFSET	==  6
 
 ;*************************************************************************
 ; Name: up_saveusercontext