Fix a bug in the Cortex M0 task switcher

Start of Keil compiler CPU specific switching

1 files changed, 103 insertions, 0 deletions

diff --git a/src/gos/gos_x_threads_cortexm01.h b/src/gos/gos_x_threads_cortexm01.h
new file mode 100644
index 00000000..df2d1f78
--- /dev/null
+++ b/src/gos/gos_x_threads_cortexm01.h
@@ -0,0 +1,103 @@
+/*
+ * This file is subject to the terms of the GFX License. If a copy of
+ * the license was not distributed with this file, you can obtain one at:
+ *
+ *              http://ugfx.org/license.html
+ */
+
+/**
+ * Thread Switching Functions for the Cortex M0 & M1
+ *
+ * Use the EABI calling standard (ARM's AAPCS) - Save r4 - r11
+ * The context is saved at the current stack location and a pointer is maintained in the thread structure.
+ */
+
+#if CORTEX_USE_FPU
+	#warning "GOS Threads: You have specified GFX_CPU=GFX_CPU_CORTX_M? with no hardware floating point support but CORTEX_USE_FPU is TRUE. Try using GFX_CPU_GFX_CPU_CORTEX_M?_FP instead"
+#endif
+
+#if GFX_COMPILER == GFX_COMPILER_GCC || GFX_COMPILER == GFX_COMPILER_CYGWIN || GFX_COMPILER == GFX_COMPILER_MINGW32 || GFX_COMPILER == GFX_COMPILER_MINGW64
+	#define GFX_THREADS_DONE
+	#define _gfxThreadsInit()
+
+	static __attribute__((pcs("aapcs"),naked)) void _gfxTaskSwitch(thread *oldt, thread *newt) {
+		__asm__ volatile (	"push    {r4, r5, r6, r7, lr}                   \n\t"
+							"mov     r4, r8                                 \n\t"
+							"mov     r5, r9                                 \n\t"
+							"mov     r6, r10                                \n\t"
+							"mov     r7, r11                                \n\t"
+							"push    {r4, r5, r6, r7}						\n\t"
+							"str	sp, %[oldtcxt]							\n\t"
+							"ldr	sp, %[newtcxt]							\n\t"
+							"pop     {r4, r5, r6, r7}                   	\n\t"
+							"mov     r8, r4                                 \n\t"
+							"mov     r9, r5                                 \n\t"
+							"mov     r10, r6                                \n\t"
+							"mov     r11, r7                                \n\t"
+							"pop     {r4, r5, r6, r7, pc}					\n\t"
+							: [newtcxt] "=m" (newt->cxt)
+							: [oldtcxt] "m" (oldt->cxt)
+							: "memory");
+	}
+
+	static __attribute__((pcs("aapcs"),naked)) void _gfxStartThread(thread *oldt, thread *newt) {
+		newt->cxt = (char *)newt + newt->size;
+		__asm__ volatile (	"push    {r4, r5, r6, r7, lr}                   \n\t"
+							"mov     r4, r8                                 \n\t"
+							"mov     r5, r9                                 \n\t"
+							"mov     r6, r10                                \n\t"
+							"mov     r7, r11                                \n\t"
+							"push    {r4, r5, r6, r7}						\n\t"
+							"str	sp, %[oldtcxt]							\n\t"
+							"ldr	sp, %[newtcxt]							\n\t"
+							: [newtcxt] "=m" (newt->cxt)
+							: [oldtcxt] "m" (oldt->cxt)
+							: "memory");
+
+		// Run the users function
+		gfxThreadExit(current->fn(current->param));
+	}
+
+#elif GFX_COMPILER == GFX_COMPILER_KEIL || GFX_COMPILER == GFX_COMPILER_ARMCC
+
+	static /*__arm*/ void _gfxTaskSwitch(thread *oldt, thread *newt) {
+/*		push	{r4, r5, r6, r7, lr}
+		mov     r4, r8
+		mov     r5, r9
+		mov     r6, r10
+		mov     r7, r11
+		push    {r4, r5, r6, r7}
+		str	sp, %[oldtcxt]
+		ldr	sp, %[newtcxt]
+		pop     {r4, r5, r6, r7}
+		mov     r8, r4
+		mov     r9, r5
+		mov     r10, r6
+		mov     r11, r7
+		pop     {r4, r5, r6, r7, pc}
+		: [newtcxt] "=m" (newt->cxt)
+		: [oldtcxt] "m" (oldt->cxt)
+		: "memory");
+*/	}
+
+	static /* __arm */ void _gfxStartThread(thread *oldt, thread *newt) {
+		newt->cxt = (char *)newt + newt->size;
+/*		push    {r4, r5, r6, r7, lr}
+		mov     r4, r8
+		mov     r5, r9
+		mov     r6, r10
+		mov     r7, r11
+		push    {r4, r5, r6, r7}
+		str	sp, %[oldtcxt]
+		ldr	sp, %[newtcxt]
+		: [newtcxt] "=m" (newt->cxt)
+		: [oldtcxt] "m" (oldt->cxt)
+		: "memory");
+*/
+		// Run the users function
+		gfxThreadExit(current->fn(current->param));
+	}
+
+#else
+	#warning "GOS: Threads: You have specified a specific CPU but your compiler is not supported. Defaulting to CLIB switching"
+#endif