Imported pristine psxsdk-20190410 from official repo

1 files changed, 111 insertions, 0 deletions

diff --git a/libpsx/src/cop.c b/libpsx/src/cop.c
new file mode 100644
index 0000000..04b49f5
--- /dev/null
+++ b/libpsx/src/cop.c
@@ -0,0 +1,111 @@
+#include <psx.h>
+
+unsigned int get_cop_register(unsigned char cop_num,
+							unsigned char register_num)
+{
+// Workaround for MIPS' simplicistic instruction set...	
+	
+	unsigned int instr[] =
+		{0x40020000, // cfc $v0, 0
+		  0x03E00008, // jr $ra
+		  0x00000000, // nop
+                  0x00000000}; // nop
+
+	int (*rawFunc)() = (void*)instr;
+
+// Write coprocessor register number inside instruction		  
+	instr[0] |= ( (cop_num & 3) << 26 ) | ( (register_num & 31) << 11 );
+
+// Execute modified instruction
+	return rawFunc();
+}
+
+unsigned int get_cop_ctrl_register(unsigned char cop_num,
+							unsigned char register_num)
+{
+// Workaround for MIPS' simplicistic instruction set...	
+	unsigned int instr[] =
+		{0x40420000, // mfc $v0, 0
+		  0x03E00008, // jr $ra
+		  0x00000000, // nop
+                  0x00000000}; // nop
+
+	int (*rawFunc)() = (void*)instr;
+
+// Write coprocessor register number inside instruction		  
+	instr[0] |= ( (cop_num & 3) << 26 ) | ( (register_num & 31) << 11 );
+
+// Execute modified instruction
+	return rawFunc();
+}
+
+unsigned int get_cop0_register(unsigned char register_num)
+{
+	return get_cop_register(0, register_num);
+}
+
+void set_cop_register(unsigned char cop_num,
+					unsigned char register_num,
+					unsigned int value)
+{
+// Workaround for MIPS' simplicistic instruction set...	
+	unsigned int instr[] =
+		{0x40840000, // mtc $a0, 0
+		  0x03E00008, // jr $ra
+		  0x00000000, // nop
+                  0x00000000}; // nop
+		  
+	void (*rawFunc)(int value) = (void*)instr;
+
+// Write coprocessor register number inside instruction
+	instr[0] |= ( (cop_num & 3) << 26 ) | ( (register_num & 31) << 11 );	 
+
+// Execute modified instruction
+	rawFunc(value);
+}
+
+void set_cop_ctrl_register(unsigned char cop_num,
+					unsigned char register_num,
+					unsigned int value)
+{
+// Workaround for MIPS' simplicistic instruction set...	
+	unsigned int instr[] =
+		{0x40C40000, // ctc $a0, 0
+		  0x03E00008, // jr $ra
+		  0x00000000, // nop
+                  0x00000000}; // nop
+		  
+	void (*rawFunc)(int value) = (void*)instr;
+
+// Write coprocessor register number inside instruction
+	instr[0] |= ( (cop_num & 3) << 26 ) | ( (register_num & 31) << 11 );	 
+
+// Execute modified instruction
+	rawFunc(value);
+}
+
+void set_cop0_register(unsigned char register_num,
+							unsigned int value)
+{
+	set_cop_register(0, register_num, value);
+}
+
+void run_cop_instruction(unsigned char cop_num,
+						unsigned int operation)
+{
+// Workaround for MIPS' simplicistic instruction set...	
+	unsigned int instr[] =
+		{0x42000000, // cop 0
+		  0x03E00008, // jr $ra
+		  0x00000000, // nop
+                  0x00000000}; // nop
+		  
+	void (*rawFunc)(void) = (void*)instr;
+
+// Write coprocessor register number inside instruction
+	instr[0] |= ( (cop_num & 3) << 26 ) |  (operation & 0x1ffffff);	 
+
+// Execute modified instruction
+	rawFunc();
+}
+