m68k: library-ifiy

This makes the m68k make rules usable from other makefiles.

This also adds scsp start address macros.

The sound.c example-fragment is deleted, as a better version now exists
in saturn-examples.

common.mk

@@ -3,11 +3,12 @@ OPT ?= -Og
 
 AARCH = --isa=sh2 --big
 AFLAGS = -g -gdwarf-4
+
+CARCH = -m2 -mb
 CFLAGS += -falign-functions=4 -ffunction-sections -fdata-sections -fshort-enums -ffreestanding -nostdlib
 CFLAGS += -Wall -Werror -Wfatal-errors -Wno-error=unused-variable -g -gdwarf-4 $(OPT)
 LDFLAGS = --gc-sections --no-warn-rwx-segment --print-memory-usage --entry=_start
 CXXFLAGS = -fno-exceptions -fno-rtti
-CARCH = -m2 -mb
 
 TARGET = sh2-none-elf-
 CC = $(TARGET)gcc
@@ -17,6 +18,13 @@ LD = $(TARGET)ld
 OBJCOPY = $(TARGET)objcopy
 OBJDUMP = $(TARGET)objdump
 
+define BUILD_BINARY_O
+	$(OBJCOPY) \
+		-I binary -O elf32-sh -B sh2 \
+		--rename-section .data=.data.$(basename $@) \
+		$< $@
+endef
+
 $(LIB)/sys_%.o: $(LIB)/segasmp/lib/sys_%.o
 	$(OBJCOPY) -I coff-sh -O elf32-sh -g \
 		--rename-section .text=.text.$* \
@@ -41,6 +49,9 @@ SYS_IP_OBJ += $(LIB)/smpsys.o
 %.o: %.cpp
 	$(CXX) $(CFLAGS) $(CXXFLAGS) $(CARCH) -c $< -o $@
 
+%.elf:
+	$(LD) $(LDFLAGS) -T $(LIB)/sh2.lds $^ -o $@
+
 %.bin: %.elf
 	$(OBJCOPY) -O binary $< $@
 
@@ -50,9 +61,6 @@ SYS_IP_OBJ += $(LIB)/smpsys.o
 		--rename-section .data=.rodata,alloc,load,readonly,data,contents \
 		$< $@
 
-%.elf:
-	$(LD) $(LDFLAGS) -T $(LIB)/sh2.lds $^ -o $@
-
 sys_ip.elf: $(SYS_IP_OBJ)
 	$(LD) --print-memory-usage -T $(LIB)/sys_ip.lds $^ -o $@
 

example/sound.c

@@ -1,91 +0,0 @@
-//
-// scsp
-//
-
-// The SCSP will initialize the internal registers, etc. for about 30µ sec
-// after the reset has been released.  For this reason, access is not allowed
-// during the 30µ sec.
-
-// Before downloading anything, make sure to set MEM4MB bit to 1 and DAC18B
-// bit to 0 within the sound CPU (address) 10400H address.
-
-smpc.reg.COMREG = COMREG__SNDON;
-while (smpc.reg.OREG31 != 0b00000110) {}
-for (long i = 0; i < 807; i++) { asm volatile ("nop"); }   // wait for (way) more than 30µs
-
-scsp.reg.common[0] = SCSP__0__MEM4MB | SCSP__0__DAC18B;
-
-u16 * m68k_main_start = (u16 *)&_binary_m68k_main_bin_start;
-u32 m68k_main_size = (u32)&_binary_m68k_main_bin_size;
-copy_16(m68k_main_start, &scsp.ram.u16[0], m68k_main_size);
-
-smpc.reg.COMREG = COMREG__SNDOFF;
-while (smpc.reg.OREG31 != 0b00000111) {}
-for (long i = 0; i < 807; i++) { asm volatile ("nop"); }   // wait for (way) more than 30µs
-
-smpc.reg.COMREG = COMREG__SNDON;
-while (smpc.reg.OREG31 != 0b00000110) {}
-for (long i = 0; i < 807; i++) { asm volatile ("nop"); }   // wait for (way) more than 30µs
-
-scsp.reg.common[0] = SCSP__0__MEM4MB | SCSP__0__DAC18B;
-
-///
-
-static signed int left_phase;
-
-static void fill_data(int16_t * output, int len)
-{
-  for (int i = 0; i < len; i++) {
-    *output++ = (signed short)left_phase;
-    left_phase += 327 / 2;
-    if (left_phase >= 32767) left_phase = -32768;
-  }
-}
-
-#include "scsp.h"
-
-void main_sound(void)
-{
-  while ((smpc.reg.SF & 0x01) == 1);
-
-  smpc.reg.SF = 1;
-
-  smpc.reg.COMREG = COMREG__SNDON;
-  while ((smpc.reg.SF & 0x01) == 1);
-  while (smpc.reg.OREG31 != 0b00000110) {}
-
-  for (long i = 0; i < 807; i++) { asm volatile ("nop"); }   // wait for (way) more than 30µs
-
-  scsp.reg.common[0] = SCSP__0__MEM4MB | SCSP__0__DAC18B | 15;
-
-  left_phase = 0;
-  fill_data((int16_t*)&scsp.ram.u16[0], 44100);
-
-  scsp_slot& slot = scsp.reg.slot[0];
-
-  while (1) {
-    left_phase = 0;
-    fill_data((int16_t*)&scsp.ram.u16[0], 44100);
-
-    slot.field[0] = (1 << 11) | (1 << 5); // kx
-    slot.field[1] = 0; // start_addr
-    slot.field[2] = 0; // loop start address
-    slot.field[3] = 44100; // loop end address
-    slot.field[4] = 31; // d2r d1r ar
-    //slot.field[5] = (1 << 14) | (0xf << 10) | 0; // krs dl rr (key_decay_release)
-    slot.field[5] = 31; // krs dl rr (key_decay_release)
-    slot.field[6] = 1 << 3; // tl (attenuation)
-    slot.field[7] = 0; // mdl mdxsl mdysl (fm_data)
-    slot.field[8] = 0; // oct fns (ofc_fns)
-    slot.field[9] = 0; // lfof plfows (lfo_data)
-    slot.field[10] = 0; // isel imxl (input_sel)
-    slot.field[11] = (7 << 13); // disdl dipan efpan (pan_send)
-
-    slot.field[0] |= (1 << 12);
-
-    for (int32_t i = 0; i < 800000; i++) { asm volatile ("nop"); }
-
-    slot.field[0] |= (1 << 12);
-    slot.field[0] = 0;
-  }
-}

m68k/Makefile

@@ -1,40 +0,0 @@
-ARCH = -march=68000 -mcpu=68ec000
-AARCH = $(ARCH)
-AFLAGS = -g -gdwarf-4
-
-CFLAGS += -ffunction-sections -fshort-enums -ffreestanding -nostdlib
-CFLAGS += -Wall -Werror -Wfatal-errors -g -gdwarf-4 -Og
-CARCH = $(ARCH)
-
-TARGET = m68k-none-elf-
-CC = $(TARGET)gcc
-AS = $(TARGET)as
-LD = $(TARGET)ld
-OBJCOPY = $(TARGET)objcopy
-OBJDUMP = $(TARGET)objdump
-
-all: main.bin
-
-%.o: %.s
-	$(AS) $(AARCH) $(AFLAGS) $< -o $@
-
-%.o: %.c
-	$(CC) $(CFLAGS) -c $< -o $@
-
-%.elf:
-	$(LD) --print-memory-usage -T m68k.lds $^ -o $@
-
-%.bin: %.elf
-	$(OBJCOPY) -O binary $< $@
-
-MAIN_OBJ = vectors.o main.o
-
-main.elf: $(MAIN_OBJ)
-
-clean:
-	rm -f *.iso *.o *.bin *.elf
-
-.SUFFIXES:
-.INTERMEDIATE:
-.SECONDARY:
-.PHONY: all clean

m68k/common.mk

@@ -0,0 +1,58 @@
+LIB ?= .
+OPT ?= -Og
+
+ARCH = -march=68000 -mcpu=68000
+
+AARCH = $(ARCH)
+AFLAGS = -g -gdwarf-4
+
+CARCH = $(ARCH) -mtune=68000
+CFLAGS += -falign-functions=4 -ffunction-sections -fdata-sections -fshort-enums -ffreestanding -nostdlib
+CFLAGS += -Wall -Werror -Wfatal-errors -Wno-error=unused-variable -g -gdwarf-4 $(OPT)
+LDFLAGS = --gc-sections --no-warn-rwx-segment --print-memory-usage --entry=start
+CXXFLAGS = -fno-exceptions -fno-rtti
+
+TARGET = m68k-none-elf-
+CC = $(TARGET)gcc
+CXX = $(TARGET)g++
+AS = $(TARGET)as
+LD = $(TARGET)ld
+OBJCOPY = $(TARGET)objcopy
+OBJDUMP = $(TARGET)objdump
+
+define BUILD_BINARY_O
+	$(OBJCOPY) \
+		-I binary -O elf32-m68k -B m68k \
+		--rename-section .data=.data.$(basename $@) \
+		$< $@
+endef
+
+all: main.bin
+
+%.o: %.s
+	$(AS) $(AARCH) $(AFLAGS) $< -o $@
+
+%.o: %.S
+	$(CC) $(CFLAGS) $(CARCH) -c $< -o $@
+
+%.o: %.c
+	$(CC) $(CFLAGS) $(CARCH) -c $< -o $@
+
+%.o: %.cpp
+	$(CXX) $(CFLAGS) $(CXXFLAGS) $(CARCH) -c $< -o $@
+
+%.elf:
+	$(LD) $(LDFLAGS) -T $(LIB)/m68k/m68k.lds $^ -o $@
+
+%.bin: %.elf
+	$(OBJCOPY) -O binary $< $@
+
+#OBJ = vectors.o main.o
+
+clean:
+	rm -f *.iso *.o *.bin *.elf *.cue
+
+.SUFFIXES:
+.INTERMEDIATE:
+.SECONDARY:
+.PHONY: all clean

m68k/m68k.lds

@@ -10,12 +10,15 @@ SECTIONS
   {
     . = 0x000000;
     KEEP(*(.vectors))
+    KEEP(*(.text.start))    
     *(.text)
+    *(.text.*)    
   } > sound_ram
 
   .data ALIGN(4) : SUBALIGN(4)
   {
     *(.data)
+    *(.data.*)    
   } > sound_ram
 
   .rodata ALIGN(4) : SUBALIGN(4)

m68k/main.c

@@ -1,12 +0,0 @@
-#include "../scsp.h"
-
-#define MVOL(n) (n << 0)
-
-void start(void)
-{
-  scsp.reg.common[0] = SCSP__0__MEM4MB | SCSP__0__DAC18B | MVOL(15);
-
-
-  while (1) {
-  }
-}

scsp.h

@@ -134,7 +134,7 @@ static_assert((offsetof (struct scsp, reg)) == 0x100000);
 
 // bits
 
-enum slot_bits {
+enum loop_bits {
   LOOP__KYONEX = (    1 << 12), // (KX) execute KEY_ON
   LOOP__KYONB = (     1 << 11), // (KB) record KEY_ON, KEY_OFF
   LOOP__SBCTL = (  0b00 << 9), // source bit control
@@ -144,7 +144,11 @@ enum slot_bits {
   LOOP__LPCTL__REVERSE     = (  0b10 << 5 ), // loop control
   LOOP__LPCTL__ALTERNATIVE = (  0b11 << 5 ), // loop control
   LOOP__PCM8B = (     1 << 4 ), // (8B) 8bit signed PCM
-  LOOP__SA =    (0b0000 << 0 ), // start address
+#define LOOP__SA(n) ((((n) >> 16) & 0b1111) << 0) // start address
+};
+
+enum sa_bits {
+#define SA__SA(n) ((n) & 0xffff)
 };
 
 enum eg_bits {