code wiki / _hdl_build / nx_emu_x86_dev_test.nx
`nx_emu_x86_dev_test.nx` source

1// nx_emu_x86_dev_test.nx -- x86 full-system ladder R7: DEVICE MODELS (the 16550 UART serial console).
2// x86 talks to devices over an I/O PORT space (in/out instructions).  COM1's 16550 UART sits at port
3// 0x3F8; writing a byte to it (the THR) transmits a serial character -- the console a kernel prints
4// through (the x86 twin of the rv64 UART that emitted NISHI).  io_out() models the port dispatch +
5// the UART.  KAT: a "print" routine writes "NISHI-X86" to 0x3F8 -> it lands in the UART tx buffer; a
6// write to a non-UART port (0x60 keyboard) does NOT.
7// HONEST SCOPE: the UART tx device + port dispatch; wiring io_out into the emu's OUT-instruction
8// decode (EE / E6) + timer (PIT/APIC) + disk (ATA/AHCI/virtio) models = R7 rung-2+.  R8 = an x86
9// kernel that boots through R1-R7 end-to-end.  No hardware writes (Rule 26).  expect_exit: 0  license_tier: ORIGINAL
10import "nx_syscalls.nx"
11
12const UART_COM1: i64 = 0x3F8
13
14func dv_puts(s: *u8) -> i64 { var n: i64=0; while s[n]!=(0 as u8){n=n+1} sys_write(1,s,n); return 0 }
15func dv_num(v: i64) -> i64 { let b: *u8=sys_mmap(28); var m: i64=v; if m<0{m=0-m;sys_write(1,"-" as *u8,1)} let t: *u8=sys_mmap(28); var k: i64=0; if m==0{t[0]=48 as u8;k=1} while m>0{t[k]=(48+(m%10)) as u8;m=m/10;k=k+1} var i: i64=0; while i<k{b[i]=t[k-1-i];i=i+1} sys_write(1,b,k); return 0 }
16func dv_beq(a: *u8, b: *u8, n: i64) -> i64 { var i: i64=0; while i<n { if a[i]!=b[i] { return 0 } i=i+1 } return 1 }
17
18// x86 OUT to an I/O port: COM1 UART (0x3F8) transmits a byte into uart_tx; other ports ignored here.
19func io_out(uart_tx: *u8, uart_len: *i64, port: i64, byte: i64) -> i64 {
20    if port == UART_COM1 { uart_tx[uart_len[0]] = (byte & 0xff) as u8; uart_len[0] = uart_len[0] + 1 }
21    return 0
22}
23
24func main() -> i64 {
25    dv_puts("x86 full-system ladder R7: DEVICE MODEL (16550 UART @ port 0x3F8, the x86 serial console)\n" as *u8)
26    let uart_tx: *u8 = sys_mmap(4096)
27    let uart_len: *i64 = sys_mmap(8) as *i64
28    uart_len[0] = 0
29
30    // a kernel "print" routine: write each char of "NISHI-X86" to the UART port
31    let msg: *u8 = "NISHI-X86\x00"
32    var i: i64 = 0
33    while msg[i] != (0 as u8) { io_out(uart_tx, uart_len, UART_COM1, msg[i] as i64); i = i + 1 }
34    // a write to the keyboard port (0x60) must NOT reach the UART
35    io_out(uart_tx, uart_len, 0x60, 90)   // 'Z' to port 0x60
36
37    dv_puts("  SOVEREIGN-EMU-X86 serial: " as *u8); sys_write(1, uart_tx, uart_len[0]); dv_puts("\n" as *u8)
38
39    var pass: i64=0
40    var ttl: i64=0
41    ttl=ttl+1; dv_puts("  T1 UART received 9 bytes (0x60 write ignored): " as *u8); if uart_len[0]==9 { pass=pass+1; dv_puts("PASS\n" as *u8) } else { dv_puts("FAIL\n" as *u8) }
42    ttl=ttl+1; dv_puts("  T2 UART buffer == NISHI-X86: " as *u8); if dv_beq(uart_tx, "NISHI-X86\x00" as *u8, 9)==1 { pass=pass+1; dv_puts("PASS\n" as *u8) } else { dv_puts("FAIL\n" as *u8) }
43    ttl=ttl+1; dv_puts("  T3 neg: 0x60 write did not append 'Z': " as *u8); if uart_tx[8]==(54 as u8) { pass=pass+1; dv_puts("PASS\n" as *u8) } else { dv_puts("FAIL\n" as *u8) }
44
45    dv_puts("X86-DEV-GATE passed " as *u8); dv_num(pass); dv_puts("/" as *u8); dv_num(ttl)
46    if pass==ttl { dv_puts(" verdict=GREEN (x86 serial console device; emu OUT-decode + timer/disk = R7-2+, then R8 kernel boot)\n" as *u8); sys_exit(0); return 0 }
47    dv_puts(" verdict=RED\n" as *u8); sys_exit(1); return 1
48}
nx_emu_x86_dev_test.nx source

`nx_emu_x86_dev_test.nx` source
