ref: b7105fe0662b57689f629ac768dd084f8a1589a4
dir: /sys/src/games/blit/mem.c/
#include <u.h> #include <libc.h> #include <thread.h> #include <draw.h> #include <bio.h> #include <mouse.h> #include "dat.h" #include "fns.h" u32int irq; u32int irql[8] = { [1] INTVBL, [2] INTKEY, [4] INTMOUSE, [5] INTUART, }; int diag; ushort ram[128*1024]; ushort rom[3*4096]; Channel *keych; Channel *uartrxch, *uarttxch; int mousex, mousey, mousebut; int yes; u8int kbdctrl, uartctrl; enum { ACIATXMASK = 0x60, ACIATXIRQ = 0x20, ACIARXIRQ = 0x80, }; int keybuf = -1; int uartrxbuf = -1; int uarttxbuf = -1; void meminit(void) { int i, x; Biobuf *bp; char *s; ushort *p, *q; p = rom; if(diag){ bp = Bopen("/sys/lib/blit/diagbits", OREAD); if(bp == nil) sysfatal("Bopen: %r"); Bread(bp, rom, sizeof(rom)); Bterm(bp); return; } for(i = 0; i < 6; i++){ bp = Bopen(smprint("/sys/lib/blit/rom%d", i), OREAD); if(bp == nil) sysfatal("Bopen: %r"); q = p; for(;;){ s = Brdline(bp, '\n'); if(s == nil || Blinelen(bp) == 0) break; s[Blinelen(bp) - 1] = 0; x = strtol(s, nil, 8); if((i & 1) != 0) *p |= x << 8; else *p |= x; p++; } if((i & 1) == 0) p = q; Bterm(bp); } } void keycheck(void) { yield(); if(keybuf < 0) nbrecv(keych, &keybuf); if(keybuf >= 0 && (kbdctrl & ACIARXIRQ) != 0) irq |= INTKEY; else irq &= ~INTKEY; if(uartrxbuf < 0 && uartrxctr <= 0){ nbrecv(uartrxch, &uartrxbuf); uartrxctr = FREQ * 11 / baud; } if(uarttxbuf >= 0 && nbsend(uarttxch, &uarttxbuf) > 0) uarttxbuf = -1; if(uartrxbuf >= 0 && (uartctrl & ACIARXIRQ) != 0 || uarttxbuf < 0 && (uartctrl & ACIATXMASK) == ACIATXIRQ) irq |= INTUART; else irq &= ~INTUART; } u16int memread(u32int a) { int rc; a &= 0x3fffff; if(a < 8) a += 0x40000; if(a < 0x40000) return ram[a/2]; if(a >= 0x40000 && a < 0x40000 + sizeof(rom)) return rom[(a - 0x40000)/2]; switch(a & ~1){ case 01400000: return mousey; case 01400002: return mousex; case 01400010: /* uart status */ rc = 0; if(uartrxbuf >= 0) rc |= 1; if(uarttxbuf < 0) rc |= 2; return rc | rc << 8; case 01400012: /* uart data */ rc = uartrxbuf; uartrxbuf = -1; yes=1; return rc | rc << 8; case 01400020: case 01400024: irq &= ~INTMOUSE; return mousebut | mousebut << 8; case 01400026: return 0; /* mouse: unknown purpose */ case 01400030: return daddr >> 2; /* display address */ case 01400040: return dstat; /* display status */ case 01400060: /* keyboard status */ rc = 2; if(keybuf >= 0) rc |= 1; return rc | rc << 8; case 01400062: /* keyboard data */ rc = keybuf; keybuf = -1; return rc | rc << 8; } print("read %.8o (curpc = %.6x)\n", a, curpc & 0x3fffff); return 0; } void memwrite(u32int a, u16int v, u16int m) { extern Rectangle updated; int x, y; a &= 0x3fffff; if(a < 0x40000){ if(a >= daddr){ y = (a - daddr) / 100; x = (((a & ~1) - daddr) % 100) * 8; if(updated.min.x > x) updated.min.x = x; if(updated.max.x < x+16) updated.max.x = x+16; if(updated.min.y > y) updated.min.y = y; if(updated.max.y <= y) updated.max.y = y+1; } ram[a/2] = ram[a/2] & ~m | v & m; return; } switch(a & ~1){ case 01400010: uartctrl = v; return; case 01400012: uarttxbuf = (uchar) v; return; case 01400024: return; /* mouse: purpose unknown */ case 01400026: return; /* mouse: purpose unknown */ case 01400030: daddr = ((daddr >> 2) & ~m | v & m) << 2; updated = Rect(0, 0, SX, SY); return; case 01400040: dstat = dstat & ~m | v & m; invert = -(dstat & 1); updated = Rect(0, 0, SX, SY); return; case 01400056: /* sound; exact function unknown */ return; case 01400060: kbdctrl = v; return; case 01400062: /* reset keyboard */ return; case 01400070: irq &= ~INTVBL; return; case 01400156: /* sound; exact function unknown */ return; } print("write %.8o = %.4x (mask = %.4x, curpc = %.6x)\n", a, v, m, curpc & 0x3fffff); } int intack(int l) { return 24+l; }