Add support of other resets

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@464 42af7a65-404d-4744-a932-0658087f49c3

4 files changed, 121 insertions, 27 deletions

diff --git a/nuttx/arch/z80/include/z80/irq.h b/nuttx/arch/z80/include/z80/irq.h
index 12dd502c1..dbf61fe3e 100644
--- a/nuttx/arch/z80/include/z80/irq.h
+++ b/nuttx/arch/z80/include/z80/irq.h
@@ -51,8 +51,17 @@
 
 /* Z80 Interrupts */
 
-#define Z80_IRQ_SYSTIMER (0)
-#define NR_IRQS          (1)
+#define Z80_RST0         (0)
+#define Z80_RST1         (1)
+#define Z80_RST2         (2)
+#define Z80_RST3         (3)
+#define Z80_RST4         (4)
+#define Z80_RST5         (5)
+#define Z80_RST6         (6)
+#define Z80_RST7         (7)
+
+#define Z80_IRQ_SYSTIMER Z80_RST7
+#define NR_IRQS          (8)
 
 /* IRQ Stack Frame Format
  *
diff --git a/nuttx/arch/z80/src/common/up_head.asm b/nuttx/arch/z80/src/common/up_head.asm
index fd3bf20a1..3ebecda38 100644
--- a/nuttx/arch/z80/src/common/up_head.asm
+++ b/nuttx/arch/z80/src/common/up_head.asm
@@ -70,16 +70,12 @@
 	.area	START	(ABS)

 	.org	0x0000

 

-	.globl	_os_start

 	di				; Disable interrupts

-	ld	SP, #UP_STACK_END	; Set stack pointer

 	im	1			; Set interrupt mode 1

-	jp	_os_start		; jump to the OS entry point

-forever:

-	jp	forever

+	jr	_up_reset		; And boot the system

 

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

-; Interrupt handler

+; Other reset handlers

 ;

 ; Interrupt mode 1 behavior:

 ; 

@@ -92,12 +88,99 @@ forever:
 ;

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

 

-	.org   0x0038			; Int mode 1

+	.org	0x0008			; RST 1

+

+	; Save AF on the stack, set the interrupt number and jump to the

+	; common reset handling logic.

+					; Offset 8: Return PC is already on the stack

+	push	af			; Offset 7: AF (retaining flags)

+	ld	a, #1			; 1 = Z80_RST1

+	jr	_up_rstcommon		; Remaining RST handling is common

+

+	.org	0x0010			; RST 2

 

-	; Create a register frame.  SP points to top of frame + 2, pushes

-	; decrement the stack pointer.

+	; Save AF on the stack, set the interrupt number and jump to the

+	; common reset handling logic.

 					; Offset 8: Return PC is already on the stack

 	push	af			; Offset 7: AF (retaining flags)

+	ld	a, #2			; 2 = Z80_RST2

+	jr	_up_rstcommon		; Remaining RST handling is common

+

+	.org	0x0018			; RST 3

+

+	; Save AF on the stack, set the interrupt number and jump to the

+	; common reset handling logic.

+					; Offset 8: Return PC is already on the stack

+	push	af			; Offset 7: AF (retaining flags)

+	ld	a, #3			; 1 = Z80_RST3

+	jr	_up_rstcommon		; Remaining RST handling is common

+

+	.org	0x0020			; RST 4

+

+	; Save AF on the stack, set the interrupt number and jump to the

+	; common reset handling logic.

+					; Offset 8: Return PC is already on the stack

+	push	af			; Offset 7: AF (retaining flags)

+	ld	a, #4			; 1 = Z80_RST4

+	jr	_up_rstcommon		; Remaining RST handling is common

+

+	.org	0x0028			; RST 5

+

+	; Save AF on the stack, set the interrupt number and jump to the

+	; common reset handling logic.

+					; Offset 8: Return PC is already on the stack

+	push	af			; Offset 7: AF (retaining flags)

+	ld	a, #5			; 1 = Z80_RST5

+	jr	_up_rstcommon		; Remaining RST handling is common

+

+	.org	0x0030			; RST 6

+

+	; Save AF on the stack, set the interrupt number and jump to the

+	; common reset handling logic.

+					; Offset 8: Return PC is already on the stack

+	push	af			; Offset 7: AF (retaining flags)

+	ld	a, #6			; 1 = Z80_RST6

+	jr	_up_rstcommon		; Remaining RST handling is common

+

+	.org   0x0038			; Int mode 1 / RST 7

+

+	; Save AF on the stack, set the interrupt number and jump to the

+	; common reset handling logic.

+					; Offset 8: Return PC is already on the stack

+	push	af			; Offset 7: AF (retaining flags)

+	ld	a, #7			; 7 = Z80_RST7

+	jr	_up_rstcommon		; Remaining RST handling is common

+

+;**************************************************************************

+; NMI interrupt handler

+;**************************************************************************

+

+	.org   0x0066

+	retn

+

+;**************************************************************************

+; System start logic

+;**************************************************************************

+

+_up_reset:

+	ld	SP, #UP_STACK_END	; Set stack pointer

+	jp	_os_start		; jump to the OS entry point

+forever:

+	jp	forever

+

+;**************************************************************************

+; Common Interrupt handler

+;**************************************************************************

+

+_up_rstcommon:

+	; Create a register frame.  SP points to top of frame + 4, pushes

+	; decrement the stack pointer.  Already have

+	;

+	;   Offset 8: Return PC is already on the stack

+	;   Offset 7: AF (retaining flags)

+	;

+	; IRQ number is in A

+

 	push	hl			; Offset 6: HL

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

 	add	hl, sp			;    the interrupt occurred

@@ -107,21 +190,24 @@ forever:
 	push	de			; Offset 2: DE

 	push	bc			; Offset 1: BC

 

+	ld	b, a			;   Save the reset number in B

 	ld	a, i			;   Carry bit holds interrupt state

 	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

 

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

+	ld	hl, #0			; Argument #2 is the beginning of the reg structure

 	add	hl, sp			;

-	push	hl			; Place argument at the top of thest

+	push	hl			; Place argument #2 at the top of stack

+	push	bc			; Argument #1 is the Reset number

+	inc	sp			; (make byte sized)

 	call	_up_decodeirq		; Decode the IRQ

 

 	; On return, HL points to the beginning of the reg structure to restore

-	; Note that (1) the argument pushed on the stack is not popped, and (2) the

+	; Note that (1) the arguments pushed on the stack are not popped, and (2) the

 	; original stack pointer is lost.  In the normal case (no context switch),

-	; HL will contain the value of the SP before the argument was pushed.

+	; HL will contain the value of the SP before the arguments wer pushed.

 

 	ld	sp, hl			; Use the new stack pointer

 

@@ -129,21 +215,24 @@ forever:
 

 	ex	af, af'			; Select alternate AF

 	pop	af			; Offset 0: AF' = I with interrupt state in carry

+	ex	af, af'			;   Restore original AF

 	pop	bc			; Offset 1: BC

 	pop	de			; Offset 2: DE

 	pop	ix			; Offset 3: IX

 	pop	iy			; Offset 4: IY

 	exx				;   Use alternate BC/DE/HL

-	pop	hl			; Offset 5: HL' = Stack pointer at time of interrupt

-	exx

+	ld	hl, #-2			;   Offset of SP to account for ret addr on stack

+	pop	de			; Offset 5: HL' = Stack pointer after return

+	add	hl, de			;   HL = Stack pointer value before return

+	exx				;   Restore original BC/DE/HL

 	pop	hl			; Offset 6: HL

 	pop	af			; Offset 7: AF

 

 	; Restore the stack pointer

 

-	exx

-	ld	sp, hl

-	exx

+	exx				; Use alternate BC/DE/HL

+	ld	sp, hl			; Set SP = saved stack pointer value before return

+	exx				; Restore original BC/DE/HL

 

 	; Restore interrupt state

 

@@ -156,11 +245,6 @@ nointenable:
 	ex	af, af'			; Restore AF

 	reti

 

-;**************************************************************************

-; NMI interrupt handler

-;**************************************************************************

 

-	.org   0x0066

-	retn

 

 

diff --git a/nuttx/arch/z80/src/common/up_initialstate.c b/nuttx/arch/z80/src/common/up_initialstate.c
index aa3090367..0e26af9a2 100644
--- a/nuttx/arch/z80/src/common/up_initialstate.c
+++ b/nuttx/arch/z80/src/common/up_initialstate.c
@@ -43,6 +43,7 @@
 #include <string.h>
 #include <nuttx/arch.h>
 
+#include "chip/chip.h"
 #include "up_internal.h"
 #include "up_arch.h"
 
@@ -84,7 +85,7 @@ void up_initial_state(_TCB *tcb)
 
   memset(xcp, 0, sizeof(struct xcptcontext));
 #ifndef CONFIG_SUPPRESS_INTERRUPTS
-  xcp->regs[XCPT_I]  = 0x0001; /* Carry flag will enable interrupts */
+  xcp->regs[XCPT_I]  = Z80_C_FLAG; /* Carry flag will enable interrupts */
 #endif
   xcp->regs[XCPT_SP] = (uint16)tcb->adj_stack_ptr;
   xcp->regs[XCPT_PC] = (uint16)tcb->start;
diff --git a/nuttx/arch/z80/src/common/up_internal.h b/nuttx/arch/z80/src/common/up_internal.h
index 89e334b36..7b0ba4474 100644
--- a/nuttx/arch/z80/src/common/up_internal.h
+++ b/nuttx/arch/z80/src/common/up_internal.h
@@ -107,7 +107,7 @@ extern int up_restoreusercontext(chipreg_t *regs);
 
 /* Supplied by board-specific logic */
 
-extern FAR chipreg_t *up_decodeirq(FAR chipreg_t *regs);
+extern FAR chipreg_t *up_decodeirq(uint8 rstno, FAR chipreg_t *regs);
 extern void up_irqinitialize(void);
 extern int  up_timerisr(int irq, FAR chipreg_t *regs);
 extern void up_lowputc(char ch) __naked;