ref: 3ba1197aeb382e1750cbb0f2567794bd4482e1e2
dir: /sys/src/cmd/io.c/
#include <u.h> #include <libc.h> char *datac[] = {0,"#P/iob","#P/iow",0,"#P/iol",0,0,0,"#P/msr"}; void main(int argc, char** argv) { int fd, size, op; ulong port; uvlong data; uchar datab[8]; data = 0; size = 1; op = -1; ARGBEGIN { case 'W': size = 2; break; case 'L': size = 4; break; case 'M': size = 8; break; case 'E': datac[1] = datac[2] = datac[4] = datac[8] = "#P/ec"; break; case 'r': op = OREAD; break; case 'w': op = OWRITE; break; default: sysfatal("bad flag %c", ARGC()); } ARGEND; if(op == -1) sysfatal("no operation selected"); if(argc < 1) sysfatal("no port selected"); if(op == OWRITE && argc < 2) sysfatal("no data selected"); port = strtoul(argv[0], 0, 0); if(op == OWRITE) data = strtoull(argv[1], 0, 0); fd = open(datac[size], op); if(fd == -1) sysfatal("open: %r"); if(op == OWRITE) { datab[0] = data; datab[1] = data >> 8; datab[2] = data >> 16; datab[3] = data >> 24; datab[4] = data >> 32; datab[5] = data >> 40; datab[6] = data >> 48; datab[7] = data >> 56; if(pwrite(fd, datab, size, port) != size) sysfatal("pwrite: %r"); } else { memset(datab, 0, 8); if(pread(fd, datab, size, port) != size) sysfatal("pread: %r"); data = datab[0] | (datab[1] << 8) | (datab[2] << 16) | (datab[3] << 24) | ((vlong)datab[4] << 32) | ((vlong)datab[5] << 40) | ((vlong)datab[6] << 48) | ((vlong)datab[7] << 56); print("0x%llx\n", data); } exits(nil); }