From 62517ed33ce5e2d872824c913d396a0af815569d Mon Sep 17 00:00:00 2001
From: richardbarry <richardbarry@1d2547de-c912-0410-9cb9-b8ca96c0e9e2>
Date: Fri, 7 Mar 2008 16:29:15 +0000
Subject: [PATCH] Get preeprocessor working correctly.

git-svn-id: https://svn.code.sf.net/p/freertos/code/trunk@248 1d2547de-c912-0410-9cb9-b8ca96c0e9e2
---
 Source/portable/GCC/PPC405_Xilinx/portasm.S | 148 ++++++++++++++++++++
 1 file changed, 148 insertions(+)
 create mode 100644 Source/portable/GCC/PPC405_Xilinx/portasm.S

diff --git a/Source/portable/GCC/PPC405_Xilinx/portasm.S b/Source/portable/GCC/PPC405_Xilinx/portasm.S
new file mode 100644
index 000000000..729231384
--- /dev/null
+++ b/Source/portable/GCC/PPC405_Xilinx/portasm.S
@@ -0,0 +1,148 @@
+#include "FreeRTOSConfig.h"
+
+	.extern pxCurrentTCB
+	.extern vTaskSwitchContext
+	.extern vTaskIncrementTick
+	.extern vPortISRHandler
+
+	.global vPortStartFirstTask
+	.global vPortYield
+	.global vPortTickISR
+	.global vPortISRWrapper
+
+.set	BChainField, 0
+.set	NextLRField, BChainField + 4
+.set	MSRField,    NextLRField + 4
+.set	PCField,     MSRField    + 4
+.set	LRField,     PCField     + 4
+.set	CTRField,    LRField     + 4
+.set	XERField,    CTRField    + 4
+.set	CRField,     XERField    + 4
+.set	USPRG0Field, CRField     + 4
+.set	r0Field,     USPRG0Field + 4
+.set	r2Field,     r0Field     + 4
+.set	r3r31Field,  r2Field     + 4
+.set	IFrameSize,  r3r31Field  + ( ( 31 - 3 ) + 1 ) * 4
+
+
+.macro portSAVE_STACK_POINTER_AND_LR
+
+	/* Get the address of the TCB. */
+	xor		R0, R0, R0
+	addis	R2, R0, pxCurrentTCB@ha
+	lwz		R2,	pxCurrentTCB@l( R2 )
+
+	/* Store the stack pointer into the TCB */
+	stw		SP,	0( R2 )
+
+	/* Save the link register */
+	stwu	R1, -24( R1 )
+	mflr	R0
+	stw		R31, 20( R1 )
+	stw		R0, 28( R1 )
+	mr		R31, r1
+
+.endm
+
+.macro portRESTORE_STACK_POINTER_AND_LR
+
+	/* Restore the link register */
+	lwz		R11, 0( R1 )
+	lwz		R0, 4( R11 )
+	mtlr	R0
+	lwz		R31, -4( R11 )
+	mr		R1, R11
+
+	/* Get the address of the TCB. */
+	xor		R0, R0, R0
+	addis   SP, R0, pxCurrentTCB@ha
+	lwz		SP,	pxCurrentTCB@l( R1 )
+
+	/* Get the task stack pointer from the TCB. */
+	lwz		SP, 0( SP )
+
+.endm
+
+
+vPortStartFirstTask:
+
+	/* Get the address of the TCB. */
+	xor		R0, R0, R0
+    addis   SP, R0, pxCurrentTCB@ha
+    lwz		SP,	pxCurrentTCB@l( SP )
+
+	/* Get the task stack pointer from the TCB. */
+	lwz		SP, 0( SP )
+	
+	/* Restore MSR register to SRR1. */
+	lwz		R0, MSRField(R1)
+	mtsrr1	R0
+	
+	/* Restore current PC location to SRR0. */
+	lwz		R0, PCField(R1)
+	mtsrr0	R0
+
+	/* Save  USPRG0 register */
+	lwz		R0, USPRG0Field(R1)
+	mtspr	0x100,R0
+	
+	/* Restore Condition register */
+	lwz		R0, CRField(R1)
+	mtcr	R0
+	
+	/* Restore Fixed Point Exception register */
+	lwz		R0, XERField(R1)
+	mtxer	R0
+	
+	/* Restore Counter register */
+	lwz		R0, CTRField(R1)
+	mtctr	R0
+	
+	/* Restore Link register */
+	lwz		R0, LRField(R1)
+	mtlr	R0
+	
+	/* Restore remaining GPR registers. */
+	lmw	R3,r3r31Field(R1)
+	
+	/* Restore r0 and r2. */
+	lwz		R0, r0Field(R1)
+	lwz		R2, r2Field(R1)
+	
+	/* Remove frame from stack */
+	addi	R1,R1,IFrameSize
+
+	/* Return into the first task */
+	rfi
+
+
+
+vPortYield:
+
+	portSAVE_STACK_POINTER_AND_LR
+	bl vTaskSwitchContext
+	portRESTORE_STACK_POINTER_AND_LR
+	blr
+
+vPortTickISR:
+
+	portSAVE_STACK_POINTER_AND_LR
+	bl vTaskIncrementTick
+	
+	#if configUSE_PREEMPTION == 1
+		bl vTaskSwitchContext
+	#endif
+
+	/* Clear the interrupt */
+	lis		R0, 2048
+	mttsr	R0
+
+	portRESTORE_STACK_POINTER_AND_LR
+	blr
+
+vPortISRWrapper:
+
+	portSAVE_STACK_POINTER_AND_LR
+	bl vPortISRHandler
+	portRESTORE_STACK_POINTER_AND_LR
+	blr
-- 
2.39.5