emul: make stage2 load z80a from blkfs

This allows us to remove forth/z80a.fs. Another big step towards
self-hosting!

blk/212

@@ -2,7 +2,7 @@
 H@ 0x59 RAM+ !
 10 ALLOT
 
-213 LOAD 215 LOAD 216 LOAD 217 LOAD 218 LOAD 220 LOAD 222 LOAD
+213 LOAD 215 LOAD 216 LOAD 217 LOAD 218 LOAD 219 LOAD
-223 LOAD 224 LOAD 226 LOAD 228 LOAD 230 LOAD 232 LOAD 234 LOAD
+220 LOAD 222 LOAD 223 LOAD 224 LOAD 226 LOAD 228 LOAD
-236 LOAD 238 LOAD 240 LOAD 242 LOAD 243 LOAD 244 LOAD 246 LOAD
+230 LOAD 232 LOAD 234 LOAD 236 LOAD 238 LOAD 240 LOAD
-247 LOAD
+242 LOAD 243 LOAD 244 LOAD 246 LOAD 247 LOAD

blk/218

@@ -1,11 +1,10 @@
 ( r -- )
-: OP1r0
+: OP1r
     CREATE C,
     DOES>
     C@              ( r op )
+    SWAP            ( op r )
+    <<3             ( op r<<3 )
     OR A,
 ;
-0x80 OP1r0 ADDr,               0x88 OP1r0 ADCr,
+0x04 OP1r INCr,                0x05 OP1r DECr,
-0xa0 OP1r0 ANDr,               0xb8 OP1r0 CPr,
-0xb0 OP1r0 ORr,                0x90 OP1r0 SUBr,
-0x98 OP1r0 SBCr,               0xa8 OP1r0 XORr,

blk/219

@@ -0,0 +1,13 @@
+( also works for cc )
+0xc0 OP1r RETcc,
+( r -- )
+: OP1r0
+    CREATE C,
+    DOES>
+    C@              ( r op )
+    OR A,
+;
+0x80 OP1r0 ADDr,               0x88 OP1r0 ADCr,
+0xa0 OP1r0 ANDr,               0xb8 OP1r0 CPr,
+0xb0 OP1r0 ORr,                0x90 OP1r0 SUBr,
+0x98 OP1r0 SBCr,               0xa8 OP1r0 XORr,

emul/Makefile

@@ -8,8 +8,7 @@ BOOTSRCS = ./forth/conf.fs \
 	../forth/icore.fs \
 	./forth/xstop.fs
 
-FORTHSRCS = core.fs cmp.fs print.fs str.fs parse.fs readln.fs fmt.fs z80a.fs \
+FORTHSRCS = core.fs cmp.fs print.fs str.fs parse.fs readln.fs fmt.fs blk.fs
-	link.fs blk.fs
 FORTHSRC_PATHS = ${FORTHSRCS:%=../forth/%} forth/run.fs
 OBJS = emul.o libz80/libz80.o
 SLATEST = ../tools/slatest
@@ -58,12 +57,15 @@ forth/forth1.bin: forth/core.bin $(SLATEST)
 forth/forth1-bin.h: forth/forth1.bin $(BIN2C)
 	$(BIN2C) KERNEL < forth/forth1.bin > $@
 
-forth/stage2: forth/stage.c $(OBJS) forth/forth1-bin.h 
+forth/stage2: forth/stage.c $(OBJS) forth/forth1-bin.h forth/blkfs-bin.h
 	$(CC) -DSTAGE2 forth/stage.c $(OBJS) -o $@
 
 blkfs: $(BLKPACK)
 	$(BLKPACK) ../blk > $@
 
+forth/blkfs-bin.h: blkfs $(BIN2C)
+	$(BIN2C) BLKFS < blkfs > $@
+
 forth/forth: forth/forth.c $(OBJS) forth/forth1-bin.h blkfs
 	$(CC) forth/forth.c $(OBJS) -o $@
 

emul/forth/conf.fs

@@ -1,2 +1,3 @@
+212 LOAD  ( z80 assembler )
 0xe800 CONSTANT RAMSTART
 0xf000 CONSTANT RS_ADDR

emul/forth/run.fs

@@ -18,7 +18,6 @@
     ['] EFS@ BLK@* !
     ['] EFS! BLK!* !
     RDLN$
-    Z80A$
     LIT< _sys [entry]
     INTERPRET
 ;

emul/forth/stage.c

@@ -4,6 +4,7 @@
 #include "../emul.h"
 #ifdef STAGE2
 #include "forth1-bin.h"
+#include "blkfs-bin.h"
 #else
 #include "forth0-bin.h"
 #endif
@@ -34,6 +35,10 @@ trouble of compiling defs to binary.
 // To know which part of RAM to dump, we listen to port 2, which at the end of
 // its compilation process, spits its HERE addr to port 2 (MSB first)
 #define HERE_PORT 0x02
+// Port for block reads. Write 2 bytes, MSB first, on that port and then
+// read 1024 bytes from the DATA port.
+#define BLK_PORT 0x03
+#define BLKDATA_PORT 0x04
 
 static int running;
 // We support double-pokes, that is, a first poke to tell where to start the
@@ -41,6 +46,8 @@ static int running;
 // then ending HERE and we start at sizeof(KERNEL).
 static uint16_t start_here = 0;
 static uint16_t end_here = 0;
+static uint16_t blkid = 0;
+static unsigned int blkpos = 0;
 
 static uint8_t iord_stdio()
 {
@@ -68,6 +75,20 @@ static void iowr_here(uint8_t val)
     end_here |= val;
 }
 
+#ifdef STAGE2
+static void iowr_blk(uint8_t val)
+{
+    blkid <<= 8;
+    blkid |= val;
+    blkpos = blkid * 1024;
+}
+
+static uint8_t iord_blkdata()
+{
+    return BLKFS[blkpos++];
+}
+#endif
+
 int main(int argc, char *argv[])
 {
     Machine *m = emul_init();
@@ -75,6 +96,10 @@ int main(int argc, char *argv[])
     m->iord[STDIO_PORT] = iord_stdio;
     m->iowr[STDIO_PORT] = iowr_stdio;
     m->iowr[HERE_PORT] = iowr_here;
+#ifdef STAGE2
+    m->iowr[BLK_PORT] = iowr_blk;
+    m->iord[BLKDATA_PORT] = iord_blkdata;
+#endif
     // initialize memory
     for (int i=0; i<sizeof(KERNEL); i++) {
         m->mem[i] = KERNEL[i];

forth/z80a.fs

@@ -1,392 +0,0 @@
-( Z80 assembler )
-
-: Z80AMEM+ 0x59 RAM+ @ + ;
-
-( H@ offset at which we consider our PC 0. Used to compute
-  PC. To have a proper PC, call  "H@ ORG !" at the beginning
-  of your assembly process. )
-: ORG 0 Z80AMEM+ ;
-
-( Labels are a convenient way of managing relative jump
-  calculations. Backward labels are easy. It is only a matter
-  or recording "HERE" and do subtractions. Forward labels
-  record the place where we should write the offset, and then
-  when we get to that point later on, the label records the
-  offset there.
-
-  To avoid using dict memory in compilation targets, we
-  pre-declare label variables here, which means we have a
-  limited number of it. For now, 4 ought to be enough. )
-: L1 2 Z80AMEM+ ;
-: L2 4 Z80AMEM+ ;
-: L3 6 Z80AMEM+ ;
-: L4 8 Z80AMEM+ ;
-
-: Z80A$
-    ( 59 == z80a's memory )
-    H@ 0x59 RAM+ !
-    10 ALLOT
-;
-
-( Splits word into msb/lsb, lsb being on TOS )
-: SPLITB
-    256 /MOD SWAP
-;
-
-
-: PC H@ ORG @ - ;
-
-( A, spits an assembled byte, A,, spits an assembled word
-  Both increase PC. To debug, change C, to .X )
-: A, C, ;
-: A,, SPLITB A, A, ;
-
-( "r" register constants )
-7 CONSTANT A
-0 CONSTANT B
-1 CONSTANT C
-2 CONSTANT D
-3 CONSTANT E
-4 CONSTANT H
-5 CONSTANT L
-6 CONSTANT (HL)
-
-( "ss" register constants )
-0 CONSTANT BC
-1 CONSTANT DE
-2 CONSTANT HL
-3 CONSTANT AF
-3 CONSTANT SP
-
-( "cc" condition constants )
-0 CONSTANT CNZ
-1 CONSTANT CZ
-2 CONSTANT CNC
-3 CONSTANT CC
-4 CONSTANT CPO
-5 CONSTANT CPE
-6 CONSTANT CP
-7 CONSTANT CM
-
-( As a general rule, IX and IY are equivalent to spitting an
-  extra 0xdd / 0xfd and then spit the equivalent of HL )
-: IX 0xdd A, HL ;
-: IY 0xfd A, HL ;
-: _ix+- 0xff AND 0xdd A, (HL) ;
-: _iy+- 0xff AND 0xfd A, (HL) ;
-: IX+ _ix+- ;
-: IX- 0 -^ _ix+- ;
-: IY+ _iy+- ;
-: IY- 0 -^ _iy+- ;
-
-: <<3 8 * ;
-: <<4 16 * ;
-
-( -- )
-: OP1 CREATE C, DOES> C@ A, ;
-0xf3 OP1 DI,
-0xfb OP1 EI,
-0xeb OP1 EXDEHL,
-0xd9 OP1 EXX,
-0x76 OP1 HALT,
-0xe9 OP1 JP(HL),
-0x12 OP1 LD(DE)A,
-0x1a OP1 LDA(DE),
-0x00 OP1 NOP,
-0xc9 OP1 RET,
-0x17 OP1 RLA,
-0x07 OP1 RLCA,
-0x1f OP1 RRA,
-0x0f OP1 RRCA,
-0x37 OP1 SCF,
-
-( Relative jumps are a bit special. They're supposed to take
-  an argument, but they don't take it so they can work with
-  the label system. Therefore, relative jumps are an OP1 but
-  when you use them, you're expected to write the offset
-  afterwards yourself. )
-
-0x18 OP1 JR,
-0x38 OP1 JRC,
-0x30 OP1 JRNC,
-0x28 OP1 JRZ,
-0x20 OP1 JRNZ,
-0x10 OP1 DJNZ,
-
-( r -- )
-: OP1r
-    CREATE C,
-    DOES>
-    C@              ( r op )
-    SWAP            ( op r )
-    <<3             ( op r<<3 )
-    OR A,
-;
-0x04 OP1r INCr,
-0x05 OP1r DECr,
-( also works for cc )
-0xc0 OP1r RETcc,
-
-( r -- )
-: OP1r0
-    CREATE C,
-    DOES>
-    C@              ( r op )
-    OR A,
-;
-0x80 OP1r0 ADDr,
-0x88 OP1r0 ADCr,
-0xa0 OP1r0 ANDr,
-0xb8 OP1r0 CPr,
-0xb0 OP1r0 ORr,
-0x90 OP1r0 SUBr,
-0x98 OP1r0 SBCr,
-0xa8 OP1r0 XORr,
-
-( qq -- also works for ss )
-: OP1qq
-    CREATE C,
-    DOES>
-    C@              ( qq op )
-    SWAP            ( op qq )
-    <<4             ( op qq<<4 )
-    OR A,
-;
-0xc5 OP1qq PUSHqq,
-0xc1 OP1qq POPqq,
-0x03 OP1qq INCss,
-0x0b OP1qq DECss,
-0x09 OP1qq ADDHLss,
-
-: ADDIXss, 0xdd A, ADDHLss, ;
-: ADDIXIX, HL ADDIXss, ;
-: ADDIYss, 0xfd A, ADDHLss, ;
-: ADDIYIY, HL ADDIYss, ;
-
-: _1rr
-    C@              ( rd rr op )
-    ROT             ( rr op rd )
-    <<3             ( rr op rd<<3 )
-    OR OR A,
-;
-
-( rd rr )
-: OP1rr
-    CREATE C,
-    DOES>
-    _1rr
-;
-0x40 OP1rr LDrr,
-
-( ixy+- HL rd )
-: LDIXYr,
-    ( dd/fd has already been spit )
-    LDrr,           ( ixy+- )
-    A,
-;
-
-( rd ixy+- HL )
-: LDrIXY,
-    ROT             ( ixy+- HL rd )
-    SWAP            ( ixy+- rd HL )
-    LDIXYr,
-;
-
-: OP2 CREATE , DOES> @ 256 /MOD A, A, ;
-0xedb1 OP2 CPIR,
-0xed46 OP2 IM0,
-0xed56 OP2 IM1,
-0xed5e OP2 IM2,
-0xed44 OP2 NEG,
-0xed4d OP2 RETI,
-
-( n -- )
-: OP2n
-    CREATE C,
-    DOES>
-    C@ A, A,
-;
-0xd3 OP2n OUTnA,
-0xdb OP2n INAn,
-0xc6 OP2n ADDn,
-0xe6 OP2n ANDn,
-0xf6 OP2n ORn,
-0xd6 OP2n SUBn,
-
-( r n -- )
-: OP2rn
-    CREATE C,
-    DOES>
-    C@              ( r n op )
-    ROT             ( n op r )
-    <<3             ( n op r<<3 )
-    OR A, A,
-;
-0x06 OP2rn LDrn,
-
-( b r -- )
-: OP2br
-    CREATE C,
-    DOES>
-    0xcb A,
-    C@              ( b r op )
-    ROT             ( r op b )
-    <<3             ( r op b<<3 )
-    OR OR A,
-;
-0xc0 OP2br SETbr,
-0x80 OP2br RESbr,
-0x40 OP2br BITbr,
-
-( bitwise rotation ops have a similar sig )
-( r -- )
-: OProt
-    CREATE C,
-    DOES>
-    0xcb A,
-    C@              ( r op )
-    OR A,
-;
-0x10 OProt RLr,
-0x00 OProt RLCr,
-0x18 OProt RRr,
-0x08 OProt RRCr,
-0x20 OProt SLAr,
-0x38 OProt SRLr,
-
-( cell contains both bytes. MSB is spit as-is, LSB is ORed with r )
-( r -- )
-: OP2r
-    CREATE ,
-    DOES>
-    @ SPLITB SWAP   ( r lsb msb )
-    A,              ( r lsb )
-    SWAP <<3        ( lsb r<<3 )
-    OR A,
-;
-0xed41 OP2r OUT(C)r,
-0xed40 OP2r INr(C),
-
-( ss -- )
-: OP2ss
-    CREATE C,
-    DOES>
-    0xed A,
-    C@ SWAP         ( op ss )
-    <<4             ( op ss<< 4 )
-    OR A,
-;
-0x4a OP2ss ADCHLss,
-0x42 OP2ss SBCHLss,
-
-( dd nn -- )
-: OP3ddnn
-    CREATE C,
-    DOES>
-    C@              ( dd nn op )
-    ROT             ( nn op dd )
-    <<4             ( nn op dd<<4 )
-    OR A,
-    A,,
-;
-0x01 OP3ddnn LDddnn,
-
-( nn -- )
-: OP3nn
-    CREATE C,
-    DOES>
-    C@ A,
-    A,,
-;
-0xcd OP3nn CALLnn,
-0xc3 OP3nn JPnn,
-0x22 OP3nn LD(nn)HL,
-0x2a OP3nn LDHL(nn),
-
-( Specials )
-
-( dd nn -- )
-: LDdd(nn),
-    0xed A,
-    SWAP <<4 0x4b OR A,
-    A,,
-;
-
-( nn dd -- )
-: LD(nn)dd,
-    0xed A,
-    <<4 0x43 OR A,
-    A,,
-;
-
-: JP(IX), IX DROP JP(HL), ;
-: JP(IY), IY DROP JP(HL), ;
-
-( 26 == next )
-: JPNEXT, 26 JPnn, ;
-
-: CODE
-    ( same as CREATE, but with native word )
-    (entry)
-    ( 23 == nativeWord )
-    23 C,
-;
-
-: ;CODE JPNEXT, ;
-
-
-( Macros )
-( clear carry + SBC )
-: SUBHLss, A ORr, SBCHLss, ;
-
-( Routines )
-( 29 == chkPS )
-: chkPS, 29 CALLnn, ;
-
-( Flow
-
-  There are 2 label types: backward and forward. For each
-  type, there are two actions: set and write. Setting a label
-  is declaring where it is. It has to be performed at the
-  label's destination. Writing a label is writing its offset
-  difference to the binary result. It has to be done right
-  after a relative jump operation. Yes, labels are only for
-  relative jumps.
-
-  For backward labels, set happens before write. For forward
-  labels, write happen before set. The write operation writes
-  a dummy placeholder, and then the set operation writes the
-  offset at that placeholder's address.
-
-  Variable actions are expected to be called with labels in
-  front of them. Example, "L2 FSET"
-
-  About that "1 -": z80 relative jumps record "e-2", that is,
-  the offset that *counts the 2 bytes of the jump itself*.
-  Because we set the label *after* the jump OP1 itself, that's
-  1 byte that is taken care of. We still need to adjust by
-  another byte before writing the offset.
-)
-
-( Place BEGIN, where you want to jump back and AGAIN after
-  a relative jump operator. Just like BSET and BWR. )
-: BEGIN, PC ;
-: AGAIN, PC - 1- A, ;
-
-: BSET PC SWAP ! ;
-: BWR @ AGAIN, ;
-( same as BSET, but we need to write a placeholder )
-: FJR, PC 0 A, ;
-: IFZ, JRNZ, FJR, ;
-: IFNZ, JRZ, FJR, ;
-: IFC, JRNC, FJR, ;
-: IFNC, JRC, FJR, ;
-: THEN,
-    DUP PC          ( l l pc )
-    -^ 1-           ( l off )
-    ( warning: l is a PC offset, not a mem addr! )
-    SWAP ORG @ +    ( off addr )
-    C!
-;
-: FWR BSET 0 A, ;
-: FSET @ THEN, ;