better goblin (+accel) in SBus

nubus-to-ztex-gateware/blit_goblin.c

@@ -221,7 +221,14 @@ void from_reset(void) {
 	struct goblin_bt_regs* fbt = (struct goblin_bt_regs*)BASE_BT_REGS;
 	unsigned int cmd = fbc->reg_r5_cmd;
 	uint32_t srcx, wi, dstx;
-	switch ((fbt->mode>>24) & 0xFF) { // mode is 8 bits wrong-endian (all fbt is wrong-endian)
+#if defined(GOBLIN_NUBUS)
+	switch ((fbt->mode>>24) & 0xFF)  // mode is 8 bits wrong-endian (all fbt is wrong-endian in NuBus version)
+#elif defined(GOBLIN_SBUS)
+	switch (fbt->mode & 0xFF)
+#else
+#error "Must define GOBLIN_NUBUS or GOBLIN_SBUS"
+#endif
+		{
 	case mode_32bit:
 		srcx = fbc->reg_bitblt_src_x << 2;
 		wi   = fbc->reg_width        << 2;

nubus-to-ztex-gateware/blit_goblin_sbus.lds

@@ -0,0 +1,6 @@
+OUTPUT_ARCH( "riscv" )
+SECTIONS
+{
+  . = 0x00410000;
+  .text : { *(.text) }
+}

nubus-to-ztex-gateware/blit_goblin_sbus.sh

@@ -0,0 +1,28 @@
+#!/bin/bash -x
+
+BASE_FB=${1:-0x8F000000}
+
+GCCDIR=~/LITEX/riscv64-unknown-elf-gcc-10.1.0-2020.08.2-x86_64-linux-ubuntu14
+GCCPFX=riscv64-unknown-elf-
+GCCLINK=${GCCDIR}/bin/${GCCPFX}gcc
+
+#GCCDIR=/opt/rv32bk
+#GCCPFX=riscv32-buildroot-linux-gnu-
+
+GCCDIR=~dolbeau2/LITEX/buildroot-rv32/output/host
+GCCPFX=riscv32-buildroot-linux-gnu-
+
+GCC=${GCCDIR}/bin/${GCCPFX}gcc
+OBJCOPY=${GCCDIR}/bin/${GCCPFX}objcopy
+
+OPT=-O3 #-fno-inline
+ARCH=rv32im_zba_zbb_zbt
+
+PARAM="-DBASE_FB=${BASE_FB} -DGOBLIN_SBUS"
+
+if test "x$1" != "xASM"; then
+	$GCC $OPT -S -o blit_goblin.s $PARAM -march=$ARCH -mabi=ilp32 -mstrict-align -fno-builtin-memset -nostdlib -ffreestanding -nostartfiles blit_goblin.c
+fi
+$GCC     $OPT -c -o blit_goblin.o $PARAM -march=$ARCH -mabi=ilp32 -mstrict-align -fno-builtin-memset -nostdlib -ffreestanding -nostartfiles blit_goblin.s &&
+$GCCLINK $OPT    -o blit_goblin   $PARAM -march=$ARCH -mabi=ilp32 -T blit_goblin_sbus.lds  -nostartfiles blit_goblin.o &&
+$OBJCOPY  -O binary -j .text -j .rodata blit_goblin blit_goblin.raw

nubus-to-ztex-gateware/goblin_accel.py

@@ -134,7 +134,7 @@ class GoblinAccel(Module): # AutoCSR ?
         FUN_PATT_BIT = 2
         FUN_TEST_BIT = 3
         # to hold the Vex in reset
-        local_reset = Signal(reset = 1)
+        self.local_reset = local_reset = Signal(reset = 1)
 
         self.sync += [
             If(reg_r5_cmd[FUN_DONE_BIT],
@@ -168,9 +168,7 @@ class GoblinAccel(Module): # AutoCSR ?
                    #timeout.eq(timeout_rst),
             )
         ]
-
-        #led0 = platform.request("user_led", 0)
-        #self.comb += led0.eq(~local_reset)        # Vex connection to the primary bus
+        
         self.ibus = ibus = wishbone.Interface()
         #self.dbus = dbus = wishbone.Interface()
         vex_reset = Signal()
@@ -288,5 +286,13 @@ class GoblinAccel(Module): # AutoCSR ?
     def get_netlist_name(self):
         return "VexRiscv"
 
+class GoblinAccelNuBus(GoblinAccel):
     def add_sources(self, platform):
-        platform.add_source("/home/dolbeau/NuBusFPGA/nubus-to-ztex-gateware/VexRiscv_FbAccel.v", "verilog")
+        platform.add_source("/home/dolbeau/NuBusFPGA/nubus-to-ztex-gateware/VexRiscv_GoblinAccel_NuBus.v", "verilog")
+
+
+class GoblinAccelSBus(GoblinAccel):
+    def add_sources(self, platform):
+        led0 = platform.request("SBUS_DATA_OE_LED")
+        self.comb += [ led0.eq(~self.local_reset), ]
+        platform.add_source("/home/dolbeau/NuBusFPGA/nubus-to-ztex-gateware/VexRiscv_GoblinAccel_SBus.v", "verilog")

nubus-to-ztex-gateware/nubus_to_fpga_soc.py

@@ -399,7 +399,7 @@ class NuBusFPGA(SoCCore):
             #self.comb += pad_user_led_0.eq(self.goblin.video_framebuffer.underflow)
             #self.comb += pad_user_led_1.eq(self.goblin.video_framebuffer.fb_dma.enable)
             if (True):
-                self.submodules.goblin_accel = goblin_accel.GoblinAccel(soc = self)
+                self.submodules.goblin_accel = goblin_accel.GoblinAccelNuBus(soc = self)
                 self.bus.add_slave("goblin_accel", self.goblin_accel.bus, SoCRegion(origin=self.mem_map.get("goblin_accel", None), size=0x1000, cached=False))
                 self.bus.add_master(name="goblin_accel_r5_i", master=self.goblin_accel.ibus)
                 self.bus.add_master(name="goblin_accel_r5_d", master=self.goblin_accel.dbus)