[KERNAL] Initial 65C816 support (X16Community#281)

* Proof of Concept for resolving the clash of UDTIM with the 65C816's NMIB vector.

At $FFEA in the ROM is the jump table entry for UDTIM aka `jmp clock_update`.
In native mode, the 65C816 reads its NMIB vector from $FFEA as well. By
hardcoding the address for `clock_update`, which is an alias for
`softclock_timer_update`, to an address with the low byte $XX, the NMIB
handler can be hardcoded to $XX4C, as $4C is the opcode for an absolute `jmp`.
This PoC uses $EEEE for `softclock_timer_update` and $EE4C for the NMIB handler
as example values.

* Add 65C816 support for NMI, IRQ and BRK

* Add support for COP

* Add native IRQ handler and make sure BASIC starts in emulation mode

* Replace low RAM 65C816 detection variable with a runtime detection macro

* SCREEN: Don't clobber Y

* Handle DP and SP in native IRQ

* Use 03 instead of 01 for CPU detection

* Add native interrupt and emulated COP vectors and fully implement all interrupt types

* Add native and emulated ABORT handler

* Reorder segments so that C816_ABORT_NATIVE can sit at address

* Add dedicated vectors in KVECTORS

* Move the KERNAL signature to the SIGNATURE section (see X16Community/x16-emulator@23f1f14

* Fix COP and ABORT trampolines not being in low RAM

* 65c816.s: Indent with tabs

* Remove now-unused KVEC816 segment

* Move 65c816.s to drivers/x16/65c816/interrupt.s

* Fix SCREEN and IOBASE interrupt dispatch logic

* Add first draft of stack API

* fixup! Fix SCREEN and IOBASE interrupt dispatch logic

* fixup! Fix SCREEN and IOBASE interrupt dispatch logic

* STACK: Use an extra byte that is always  for code simplification

* Rename STACK_foo to stack_foo

* Native IRQ: Call the KERNAL emulated IRQ code directly in native mode if the emulated IRQ vector hasn't been replaced

* Add missing newline at end of files

* Explicitely annotate 65C816 code with address & index width

* fix minor error while rebasing

* [KERNAL] add legacy/c816 extended APIs (X16Community#280)

* [KERNAL] refactor, comment 65C816 native stack API

* rewording comments

* [KERNAL] implement native-capable jsrfar (X16Community#283)

* [KERNAL] implement native-capable jsrfar

* native jsrfar falls back to old code if in emulated mode

* fix off-by-one error

* fix up some logic, jmpfr need only be in one place

* Save a couple cycles here

* save a few more cycles w/ carry assumptions

* add assert for jsrfar3n

* saved one more cycle

* trivial changes

* trivial changes

* updates to comments

* updates to comments

* no need to preserve X in the native jsrfar

* fix stack misalignment issue in a 16-bit jsrfar call

* requested changes

* [KERNAL] typo in 816 native jsrfar RAM routine

* [KERNAL] add extapi16 #0 test reflector call

* [CI/CD] the first unit tests

* [CI/CD] update build deps

* [MONITOR] 65C816 emulation mode stack unwinding (X16Community#292)

* [META] remove CODEX, move DIAG 16->7 (X16Community#293)

---------

Co-authored-by: George Tokmaji <[email protected]>

.github/workflows/build.yml

@@ -13,7 +13,7 @@ jobs:
           python-version: '3.9'
       - name: Install Dependencies
         run: |
-          sudo apt-get install -y make build-essential
+          sudo apt-get install -y make build-essential libsdl2-dev
           git clone https://github.com/cc65/cc65.git
           cd cc65
           make -j4
@@ -31,6 +31,16 @@ jobs:
         if: startsWith(github.ref, 'refs/tags/r')
         run: |
           RELEASE_VERSION=$(echo "$GITHUB_REF_NAME" | grep -oP '[0-9]+$') make
+      - name: Build Test Emulator
+        run: |
+          git clone https://github.com/X16Community/x16-emulator.git
+          cd x16-emulator
+          git checkout 65c816
+          make all
+      - name: Run Unit Tests
+        run: |
+          export PATH="$(pwd)/x16-emulator:$PATH"
+          make test
       - name: Archive Build Result
         run: |
           mkdir artifact

Makefile

@@ -39,7 +39,11 @@ KERNAL_CORE_SOURCES = \
 	kernal/cbm/nmi.s \
 	kernal/cbm/irq.s \
 	kernal/cbm/util.s \
-	kernal/cbm/serial.s
+	kernal/cbm/serial.s \
+	kernal/x16/extapi.s \
+	kernal/x16/65c816/interrupt.s \
+	kernal/x16/65c816/stack.s \
+	kernal/x16/65c816/extapi16.s
 
 KERNAL_GRAPH_SOURCES = \
 	kernal/graph/graph.s \
@@ -176,10 +180,21 @@ GENERIC_DEPS = \
 	inc/banks.inc \
 	inc/jsrfar.inc \
 	inc/regs.inc \
+	inc/65c816.inc \
 	kernsup/kernsup.inc
 
 KERNAL_DEPS = \
 	$(GENERIC_DEPS) \
+	kernal/cbm/channel/channelio.s \
+	kernal/cbm/channel/clall.s \
+	kernal/cbm/channel/close.s \
+	kernal/cbm/channel/errorhandler.s \
+	kernal/cbm/channel/load.s \
+	kernal/cbm/channel/messages.s \
+	kernal/cbm/channel/open.s \
+	kernal/cbm/channel/openchannel.s \
+	kernal/cbm/channel/save.s \
+	kernal/cbm/channel/x16additions.s \
 	$(GIT_SIGNATURE)
 
 KEYMAP_DEPS = \
@@ -294,15 +309,14 @@ BANK_BINS = \
 	$(BUILD_DIR)/basic.bin \
 	$(BUILD_DIR)/monitor.bin \
 	$(BUILD_DIR)/charset.bin \
-	$(BUILD_DIR)/codex.bin \
+	$(BUILD_DIR)/diag.bin \
 	$(BUILD_DIR)/graph.bin \
 	$(BUILD_DIR)/demo.bin \
 	$(BUILD_DIR)/audio.bin \
 	$(BUILD_DIR)/util.bin \
 	$(BUILD_DIR)/bannex.bin \
 	$(BUILD_DIR)/x16edit-rom.bin \
-	$(BUILD_DIR)/basload-rom.bin \
-	$(BUILD_DIR)/diag.bin \
+	$(BUILD_DIR)/basload-rom.bin
 
 ROM_LABELS=$(BUILD_DIR)/rom_labels.h
 ROM_LST=$(BUILD_DIR)/rom_lst.h
@@ -313,6 +327,9 @@ all: $(BUILD_DIR)/rom.bin $(ROM_LABELS) $(ROM_LST)
 $(BUILD_DIR)/rom.bin: $(BANK_BINS)
 	cat $(BANK_BINS) > $@
 
+test: FORCE $(BUILD_DIR)/rom.bin
+	for f in test/unit/*/*.py; do PYTHONPATH="test/unit" python3 -B $${f}; done
+
 x16edit_update:
 	@rm -rf x16edittmp
 	git clone https://github.com/stefan-b-jakobsson/x16-edit.git x16edittmp
@@ -330,7 +347,6 @@ basload_update:
 clean:
 	rm -f $(GIT_SIGNATURE)
 	rm -rf $(BUILD_DIR)
-	$(MAKE) -C codex clean
 
 $(GIT_SIGNATURE): FORCE
 	@mkdir -p $(BUILD_DIR)
@@ -393,9 +409,11 @@ $(BUILD_DIR)/charset.bin: $(CHARSET_OBJS) $(CHARSET_DEPS) $(CFG_DIR)/charset-x16
 	@mkdir -p $$(dirname $@)
 	$(LD) -C $(CFG_DIR)/charset-x16.cfg $(CHARSET_OBJS) -o $@ -m $(BUILD_DIR)/charset.map -Ln $(BUILD_DIR)/charset.sym
 
-# Bank 7 : CodeX
-$(BUILD_DIR)/codex.bin: $(CFG_DIR)/codex-x16.cfg
-	$(MAKE) -C codex
+# Bank 7: Memory diagnostic
+$(BUILD_DIR)/diag.bin: $(DIAG_OBJS) $(DIAG_DEPS) $(CFG_DIR)/diag-x16.cfg
+	@mkdir -p $$(dirname $@)
+	$(LD) -C $(CFG_DIR)/diag-x16.cfg $(DIAG_OBJS) -o $@ -m $(BUILD_DIR)/diag.map -Ln $(BUILD_DIR)/diag.sym
+	./scripts/relist.py $(BUILD_DIR)/diag.map $(BUILD_DIR)/diag
 
 # Bank 8 : Graphics
 $(BUILD_DIR)/graph.bin: $(GRAPH_OBJS) $(KERNAL_DEPS) $(CFG_DIR)/graph.cfg
@@ -446,12 +464,6 @@ $(BUILD_DIR)/basload-rom.bin: $(BASLOAD_DEPS)
 	(cd basload && make clean && make)
 	cp basload/build/basload-rom.bin $(BUILD_DIR)/basload-rom.bin
 
-# Bank 10: Memory diagnostic
-$(BUILD_DIR)/diag.bin: $(DIAG_OBJS) $(DIAG_DEPS) $(CFG_DIR)/diag-x16.cfg
-	@mkdir -p $$(dirname $@)
-	$(LD) -C $(CFG_DIR)/diag-x16.cfg $(DIAG_OBJS) -o $@ -m $(BUILD_DIR)/diag.map -Ln $(BUILD_DIR)/diag.sym
-	./scripts/relist.py $(BUILD_DIR)/diag.map $(BUILD_DIR)/diag
-
 $(BUILD_DIR)/rom_labels.h: $(BANK_BINS)
 	./scripts/symbolize.sh 0 build/x16/kernal.sym   > $@
 	./scripts/symbolize.sh 1 build/x16/keymap.sym  >> $@
@@ -460,18 +472,19 @@ $(BUILD_DIR)/rom_labels.h: $(BANK_BINS)
 	./scripts/symbolize.sh 4 build/x16/basic.sym   >> $@
 	./scripts/symbolize.sh 5 build/x16/monitor.sym >> $@
 	./scripts/symbolize.sh 6 build/x16/charset.sym >> $@
+	./scripts/symbolize.sh 7 build/x16/diag.sym   >> $@
 	./scripts/symbolize.sh A build/x16/audio.sym   >> $@
 	./scripts/symbolize.sh B build/x16/util.sym    >> $@
 	./scripts/symbolize.sh C build/x16/bannex.sym  >> $@
-	./scripts/symbolize.sh 10 build/x16/diag.sym   >> $@
 
 $(BUILD_DIR)/rom_lst.h: $(BANK_BINS)
 	./scripts/trace_lst.py 0 `find build/x16/kernal/ -name \*.rlst`   > $@
 	./scripts/trace_lst.py 2 `find build/x16/dos/ -name \*.rlst`     >> $@
 	./scripts/trace_lst.py 3 `find build/x16/fat32/ -name \*.rlst`   >> $@
 	./scripts/trace_lst.py 4 `find build/x16/basic/ -name \*.rlst`   >> $@
 	./scripts/trace_lst.py 5 `find build/x16/monitor/ -name \*.rlst` >> $@
+	./scripts/trace_lst.py 7 `find build/x16/diag/ -name \*.rlst`   >> $@
 	./scripts/trace_lst.py A `find build/x16/audio/ -name \*.rlst`   >> $@
 	./scripts/trace_lst.py B `find build/x16/util/ -name \*.rlst`    >> $@
 	./scripts/trace_lst.py C `find build/x16/bannex/ -name \*.rlst`  >> $@
-	./scripts/trace_lst.py 10 `find build/x16/diag/ -name \*.rlst`   >> $@
+

basic/init.s

@@ -4,9 +4,15 @@
 	.byte BANK_BANNEX
 .endmacro
 
+.include "65c816.inc"
 .include "bannex.inc"
 
-panic	jsr clschn      ;warm start basic...
+panic	set_carry_if_65c816
+	bcc pn65c816
+	sec
+	.byte $FB       ; xce
+	clc
+pn65c816	jsr clschn      ;warm start basic...
 	lda #0          ;clear channels
 	sta channl
 	jsr stkini      ;restore stack
@@ -23,7 +29,12 @@ nerror	txa             ;get  high bit
 	jmp nerrox
 nready	jmp readyx
 
-init	jsr initv       ;go init vectors
+init	set_carry_if_65c816
+	bcc in65c816
+	sec
+	.byte $FB       ; xce
+	clc
+in65c816	jsr initv       ;go init vectors
 	jsr initcz      ;go init charget & z-page
 	jsr initms      ;go print initilization messages
 	stz ram_bank

basic/x16additions.s

@@ -64,12 +64,7 @@ monitor:
 	jmp clean_return
 
 ;***************
-codex:
-   jsr bjsrfar
-   .word $c000
-   .byte BANK_CODEX
-	; does not return
-
+codex:  ; syntax error now that CODEX is gone
 ;***************
 geos: ; syntax error now that GEOS is gone
 	ldx #errsn

cfg/audio-x16.cfgtpl

@@ -1,8 +1,8 @@
 MEMORY {
 	#include "x16.cfginc"
 
-	ROM:         start = $C000, size = $3B00, fill=yes, fillval=$AA;
-	KSUP_CODE10: start = $FB00, size = $03A8, fill=yes, fillval=$AA;
+	ROM:         start = $C000, size = $3A80, fill=yes, fillval=$AA;
+	KSUP_CODE10: start = $FA80, size = $0428, fill=yes, fillval=$AA;
 	KSUP_VEC10:  start = $FEA8, size = $0158, fill=yes, fillval=$AA;
 
 }

cfg/bannex-x16.cfgtpl

@@ -1,8 +1,8 @@
 MEMORY {
 	#include "x16.cfginc"
 
-	ANNEX:     start = $C000, size = $3B00, fill=yes, fillval=$AA;
-	KSUP_CODE12: start = $FB00, size = $03A8, fill=yes, fillval=$AA;
+	ANNEX:     start = $C000, size = $3A80, fill=yes, fillval=$AA;
+	KSUP_CODE12: start = $FA80, size = $0428, fill=yes, fillval=$AA;
 	KSUP_VEC12:  start = $FEA8, size = $0158, fill=yes, fillval=$AA;
 }
 

cfg/codex-x16.cfgtpl

@@ -1,11 +1,11 @@
 MEMORY {
 	#include "x16.cfginc"
 
-    MAIN:     file = %O, define = yes, start = $C000, size = $3AE2, fill=yes  fillval=$A3;
+    MAIN:     file = %O, define = yes, start = $C000, size = $3A72, fill=yes  fillval=$A3;
     RWRAM:    file = "",               start = $0400, size = $3FF;
     BANK:     file = "",               start = $A000, size = $2000;
-    CODEX_VECS: start = $FAE2, size = $001E, fill=yes, fillval=$A0;
-    KSUP_CODE2: start = $FB00, size = $03A8, fill=yes, fillval=$A1;
+    CODEX_VECS: start = $FA72, size = $001E, fill=yes, fillval=$A0;
+    KSUP_CODE2: start = $FA80, size = $0418, fill=yes, fillval=$A1;
     KSUP_VEC2:  start = $FEA8, size = $0158, fill=yes, fillval=$A2;
 }
 

cfg/kernal-x16.cfgtpl

@@ -17,6 +17,7 @@ SEGMENTS {
 	I2CMUTEX: 	load = I2CMUTEX, type = bss;
 	KVAR2:      load = KVAR2,    type = bss;
 
+	KRAM816S:   load = KRAM816S, type = bss;
 	GDRVVEC:    load = GDRVVEC,  type = bss;
 	KVECTORS:   load = KVECTORS, type = bss;
 	KEYMAP:     load = KEYMAP,   type = bss;
@@ -32,14 +33,25 @@ SEGMENTS {
 	PS2:      load = KERNAL,   type = ro;
 	PS2KBD:   load = KERNAL,   type = ro;
 	PS2MOUSE: load = KERNAL,   type = ro;
-	JOYSTICK: load = KERNAL,   type = ro;
-	IEEESWTCH:load = KERNAL,   type = ro;
 	SERIAL:   load = KERNAL,   type = ro;
 	MEMORY:   load = KERNAL,   type = ro;
 	LZSA:     load = KERNAL,   type = ro;
 	RS232:    load = KERNAL,   type = ro;
 	CHANNEL:  load = KERNAL,   type = ro;
 	CLOCK:    load = KERNAL,   type = ro;
+	C816_UTIL: load = KERNAL,  type = ro;
+	C816_ABORT_NATIVE: load = KERNAL, type = ro, start = $E44C; # low byte: JMP abs, high byte equals low byte of C816_CLALL_THUNK
+	JOYSTICK: load = KERNAL,   type = ro;
+	IEEESWTCH:load = KERNAL,   type = ro;
+	C816_GETIN_THUNK: load = KERNAL, type = ro, start = $E7EF;  # low byte equals high byte of C816_COP_NATIVE, high byte equals low byte of C816_BRK
+	CLOCK_TIMER: load = KERNAL, type = ro, start = $E94C;       # low byte: JMP abs, high byte equals low byte of C816_SCRORG
+	C816_SCRORG: load = KERNAL, type = ro, start = $E9E9;       # low byte equals high byte of CLOCK_TIMER, high byte chosen at random
+	C816_CLALL_THUNK: load = KERNAL, type = ro, start = $EAE4;  # low byte equals high byte of C816_ABORT_NATIVE, high byte = NOP
+	C816_BRK: load = KERNAL, type = ro, start = $EAE7;        # low byte equals high byte of C816_GETIN_THUNK, high byte = nop
+	C816_NMIB: load = KERNAL, type = ro, start = $EAEA;         # low byte equals NOP and high byte of C816_CLALL_THUNK, high byte = NOP
+	C816_COP_NATIVE: load = KERNAL, type = ro, start = $EF4C; # low byte: JMP abs, high byte equals low byte of C816_GETIN_THUNK
+	C816_COP_EMULATED: load = KERNAL, type = ro;
+	C816_ABORT_EMULATED: load = KERNAL, type = ro;
 	I2C:      load = KERNAL,   type = ro;
 	RTC:      load = KERNAL,   type = ro;
 	NVRAM:    load = KERNAL,   type = ro;
@@ -55,8 +67,12 @@ SEGMENTS {
 	SPRITES:  load = KERNAL,   type = ro;
 	VERA_DRV: load = KERNAL,   type = ro;
 	PALETTE:  load = KERNAL,   type = ro, align = $100;
-	KERNRAM:  load = KERNAL,   run = KERNRAM,  type = ro, define = yes;
+	KRAMJFAR: load = KERNAL,   run = KRAMJFAR, type = ro, define = yes;
+	KJFAR816: load = KERNAL,   run = KJFAR816, type = ro, define = yes;
 	KERNRAM2: load = KERNAL,   run = KERNRAM2, type = ro, define = yes;
+	KRAM816:  load = KERNAL,   run = KRAM816,  type = ro, define = yes;
+	KRAM02B:  load = KERNAL,   run = KRAM02B,  type = ro, define = yes;
+	KRAM816B: load = KERNAL,   run = KRAM816B, type = ro, define = yes;
 	VECB0:    load = KERNAL,   run = VECB0, type = ro, define = yes;
 	JMPTBL:   load = JMPTBL,   type = ro;
 	VECTORS:  load = VECTORS,  type = ro;

cfg/monitor-x16.cfgtpl

@@ -3,8 +3,8 @@ MEMORY {
 
 	L0220:    start = $0220, size = $0019; # overlaps with top end of BASIC input line only
 
-	BANK5:      start = $C000, size = $3B00, fill=yes, fillval=$AA;
-	KSUP_CODE2: start = $FB00, size = $03A8, fill=yes, fillval=$AA;
+	BANK5:      start = $C000, size = $3A80, fill=yes, fillval=$AA;
+	KSUP_CODE2: start = $FA80, size = $0428, fill=yes, fillval=$AA;
 	KSUP_VEC2:  start = $FEA8, size = $0158, fill=yes, fillval=$AA;
 }
 

cfg/util-x16.cfgtpl

@@ -4,8 +4,8 @@ MEMORY {
 	HEXEDITZP:   start = $0022, size = $005E, fill=no;
 	HEXEDITBSS:  start = $0200, size = $0050, fill=no;
 	MENUBSS:     start = $0200, size = $0050, fill=no;
-	ROM:         start = $C000, size = $3B00, fill=yes, fillval=$AA;
-	KSUP_CODE11: start = $FB00, size = $03A8, fill=yes, fillval=$AA;
+	ROM:         start = $C000, size = $3A80, fill=yes, fillval=$AA;
+	KSUP_CODE11: start = $FA80, size = $0428, fill=yes, fillval=$AA;
 	KSUP_VEC11:  start = $FEA8, size = $0158, fill=yes, fillval=$AA;
 
 }

cfg/x16.cfginc

@@ -21,11 +21,13 @@ ZPMATH:   start = $00A9, size = $002B; # MATH
 ZPBASIC:  start = $00D4, size = $002B; # BASIC (last byte used: $FE)
 
 /* $0200-$02FF: always-available variables and RAM code */
-KVAR:     start = $0200, size = $00BB; # KERNAL
-/*        start = $02BB, size = $0005; # reserved for KERNAL growth */
+KVAR:     start = $0200, size = $0095; # KERNAL
+KRAM816S: start = $0295, size = $0003; # KERNAL: 65C816: old stack pointer
+KJFAR816: start = $0298, size = $0019; # KERNAL: jsrfar3n
+/*        start = $02B1, size = $000F; # reserved for KERNAL growth */
 I2CMUTEX: start = $02C0, size = $0001; # I2C MUTEX FLAG
 GRAPHVAR: start = $02C1, size = $0003; # GRAPH BANK VARS
-KERNRAM:  start = $02C4, size = $0020; # KERNAL RAM code
+KRAMJFAR: start = $02C4, size = $001E; # KERNAL: jsrfar3
 GDRVVEC:  start = $02E4, size = $001C; # framebuffer driver vectors
 
 /* $0300-$0333: vectors */
@@ -34,7 +36,10 @@ KVECTORS: start = $0314, size = $002E; # KERNAL vectors
 
 /* $036A-$03FF: variables and RAM code */
 KVAR2:    start = $036A, size = $0021; # KERNAL: screen editor state
-KERNRAM2: start = $038B, size = $003F; # KERNAL: banked IRQ/NMI, fetch, stash
+KERNRAM2: start = $038B, size = $0038; # KERNAL: banked IRQ/NMI, fetch, stash
+KRAM816:  start = $038B, size = $001D; # KERNAL: 65C816: IRQ
+KRAM02B:  start = $03C3, size = $0007; # KERNAL: 65C02: __irq_ret
+KRAM816B: start = $03C3, size = $0007; # KERNAL: 65C816: free space
 FPVARS:   start = $03CA, size = $0009; # MATH
 BVARS:    start = $03D3, size = $002D; # BASIC