/* mtrr.c - Stuff for optimizing memory access Copyrights: 2002 - Linux version by Nick Kurshev Licence: GPL */ #include "config.h" #include #include #include #include #include #include #include "kernelhelper/dhahelper.h" #include "libdha.h" #if defined (__i386__) && defined (__NetBSD__) #include #if __NetBSD_Version__ > 105240000 #include #include #include #include #endif #endif int mtrr_set_type(unsigned base,unsigned size,int type) { int dhahelper_fd; dhahelper_fd = open("/dev/dhahelper",O_RDWR); if(dhahelper_fd > 0) { int retval; dhahelper_mtrr_t mtrrs; mtrrs.operation = MTRR_OP_ADD; mtrrs.start = base; mtrrs.size = size; mtrrs.type = type; retval = ioctl(dhahelper_fd, DHAHELPER_ACK_IRQ, &mtrrs); close(dhahelper_fd); return retval; } #if defined (__NetBSD__) && (__NetBSD_Version__) > 105240000 { struct mtrr *mtrrp; int n; mtrrp = malloc(sizeof (struct mtrr)); mtrrp->base = base; mtrrp->len = size; mtrrp->type = type; mtrrp->flags = MTRR_VALID | MTRR_PRIVATE; n = 1; if (i386_set_mtrr(mtrrp, &n) < 0) { free(mtrrp); return errno; } free(mtrrp); return 0; } #else { FILE * mtrr_fd; char * stype; switch(type) { case MTRR_TYPE_UNCACHABLE: stype = "uncachable"; break; case MTRR_TYPE_WRCOMB: stype = "write-combining"; break; case MTRR_TYPE_WRTHROUGH: stype = "write-through"; break; case MTRR_TYPE_WRPROT: stype = "write-protect"; break; case MTRR_TYPE_WRBACK: stype = "write-back"; break; default: return EINVAL; } mtrr_fd = fopen("/proc/mtrr","wt"); if(mtrr_fd) { char sout[256]; unsigned wr_len; sprintf(sout,"base=0x%08X size=0x%08X type=%s\n",base,size,stype); wr_len = fprintf(mtrr_fd,sout); /*printf("MTRR: %s\n",sout);*/ fclose(mtrr_fd); return wr_len == strlen(sout) ? 0 : EPERM; } } #endif return ENOSYS; }