From 315db9ebda8dfeec80d8770dd2383bec626d24bd Mon Sep 17 00:00:00 2001
From: richardbarry <richardbarry@1d2547de-c912-0410-9cb9-b8ca96c0e9e2>
Date: Tue, 30 Jun 2009 19:24:32 +0000
Subject: [PATCH] Add support for double precision floating point.

git-svn-id: https://svn.code.sf.net/p/freertos/code/trunk@790 1d2547de-c912-0410-9cb9-b8ca96c0e9e2
---
 Source/portable/GCC/PPC405_Xilinx/port.c    | 14 +++-
 Source/portable/GCC/PPC405_Xilinx/portasm.S | 90 +++++++++++++++++++++
 2 files changed, 102 insertions(+), 2 deletions(-)

diff --git a/Source/portable/GCC/PPC405_Xilinx/port.c b/Source/portable/GCC/PPC405_Xilinx/port.c
index 623543c83..882bb8b0e 100644
--- a/Source/portable/GCC/PPC405_Xilinx/port.c
+++ b/Source/portable/GCC/PPC405_Xilinx/port.c
@@ -80,6 +80,10 @@
 
 #define portINITIAL_MSR		( portCRITICAL_INTERRUPT_ENABLE | portEXTERNAL_INTERRUPT_ENABLE | portMACHINE_CHECK_ENABLE | portAPU_PRESENT | portFCM_FPU_PRESENT )
 
+
+extern const unsigned _SDA_BASE_;
+extern const unsigned _SDA2_BASE_;
+
 /*-----------------------------------------------------------*/
 
 /*
@@ -123,12 +127,18 @@ portSTACK_TYPE *pxPortInitialiseStack( portSTACK_TYPE *pxTopOfStack, pdTASK_CODE
 	pxTopOfStack--;
 
 	/* EABI stack frame. */
-	pxTopOfStack -= 30;	/* Previous backchain and LR, R31 to R4 inclusive. */
+	pxTopOfStack -= 20;	/* Previous backchain and LR, R31 to R4 inclusive. */
+
+	/* Parameters in R13. */
+	*pxTopOfStack = ( portSTACK_TYPE ) &_SDA_BASE_; /* address of the first small data area */
+	pxTopOfStack -= 10;
 
 	/* Parameters in R3. */
 	*pxTopOfStack = ( portSTACK_TYPE ) pvParameters;
 	pxTopOfStack--;
-	*pxTopOfStack = 0x02020202UL;	/* R2. */
+
+	/* Parameters in R2. */
+	*pxTopOfStack = ( portSTACK_TYPE ) &_SDA2_BASE_;	/* address of the second small data area */
 	pxTopOfStack--;
 
 	/* R1 is the stack pointer so is omitted. */
diff --git a/Source/portable/GCC/PPC405_Xilinx/portasm.S b/Source/portable/GCC/PPC405_Xilinx/portasm.S
index 252af6bb9..54cdd10a5 100644
--- a/Source/portable/GCC/PPC405_Xilinx/portasm.S
+++ b/Source/portable/GCC/PPC405_Xilinx/portasm.S
@@ -212,6 +212,49 @@ vPortSaveFPURegisters:
 	or		r0, r0, r30
 	mtmsr	r0
 
+#ifdef USE_DP_FPU
+
+	/* Buffer address is in r3.  Save each flop register into an offset from
+	this buffer address. */
+	stfd	f0, 0(r3)
+	stfd	f1, 8(r3)
+	stfd	f2, 16(r3)
+	stfd	f3, 24(r3)
+	stfd	f4, 32(r3)
+	stfd	f5, 40(r3)
+	stfd	f6, 48(r3)
+	stfd	f7, 56(r3)
+	stfd	f8, 64(r3)
+	stfd	f9, 72(r3)
+	stfd	f10, 80(r3)
+	stfd	f11, 88(r3)
+	stfd	f12, 96(r3)
+	stfd	f13, 104(r3)
+	stfd	f14, 112(r3)
+	stfd	f15, 120(r3)
+	stfd	f16, 128(r3)
+	stfd	f17, 136(r3)
+	stfd	f18, 144(r3)
+	stfd	f19, 152(r3)
+	stfd	f20, 160(r3)
+	stfd	f21, 168(r3)
+	stfd	f22, 176(r3)
+	stfd	f23, 184(r3)
+	stfd	f24, 192(r3)
+	stfd	f25, 200(r3)
+	stfd	f26, 208(r3)
+	stfd	f27, 216(r3)
+	stfd	f28, 224(r3)
+	stfd	f29, 232(r3)
+	stfd	f30, 240(r3)
+	stfd	f31, 248(r3)	
+	
+	/* Also save the FPSCR. */
+	mffs	f31
+	stfs	f31, 256(r3)
+
+#else
+
 	/* Buffer address is in r3.  Save each flop register into an offset from
 	this buffer address. */
 	stfs	f0, 0(r3)
@@ -250,6 +293,8 @@ vPortSaveFPURegisters:
 	/* Also save the FPSCR. */
 	mffs	f31
 	stfs	f31, 128(r3)
+	
+#endif
 
 	blr
 
@@ -268,6 +313,49 @@ vPortRestoreFPURegisters:
 	or		r0, r0, r30
 	mtmsr	r0
 
+#ifdef USE_DP_FPU
+
+	/* Buffer address is in r3.  Restore each flop register from an offset
+	into this buffer. 
+	
+	First the FPSCR. */
+	lfs		f31, 256(r3)
+	mtfsf	f31, 7
+
+	lfd		f0, 0(r3)
+	lfd	    f1, 8(r3)
+	lfd		f2, 16(r3)
+	lfd		f3, 24(r3)
+	lfd		f4, 32(r3)
+	lfd		f5, 40(r3)
+	lfd		f6, 48(r3)
+	lfd		f7, 56(r3)
+	lfd		f8, 64(r3)
+	lfd		f9, 72(r3)
+	lfd		f10, 80(r3)
+	lfd		f11, 88(r3)
+	lfd		f12, 96(r3)
+	lfd		f13, 104(r3)
+	lfd		f14, 112(r3)
+	lfd		f15, 120(r3)
+	lfd		f16, 128(r3)
+	lfd		f17, 136(r3)
+	lfd		f18, 144(r3)
+	lfd		f19, 152(r3)
+	lfd		f20, 160(r3)
+	lfd		f21, 168(r3)
+	lfd		f22, 176(r3)
+	lfd		f23, 184(r3)
+	lfd		f24, 192(r3)
+	lfd		f25, 200(r3)
+	lfd		f26, 208(r3)
+	lfd		f27, 216(r3)
+	lfd		f28, 224(r3)
+	lfd		f29, 232(r3)
+	lfd		f30, 240(r3)
+	lfd		f31, 248(r3)
+
+#else
 
 	/* Buffer address is in r3.  Restore each flop register from an offset
 	into this buffer. 
@@ -309,6 +397,8 @@ vPortRestoreFPURegisters:
 	lfs		f30, 120(r3)
 	lfs		f31, 124(r3)
 
+#endif
+
 	blr
 
 #endif /* configUSE_FPU. */
-- 
2.39.5