Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!utgpu!water!watmath!clyde!rutgers!lll-lcc!seismo!nbires!isis!onecom!wldrdg!n0ano
From: n0ano@wldrdg.UUCP
Newsgroups: comp.os.minix
Subject: Zenith 150 Winchester disk fix
Message-ID: <131@wldrdg.UUCP>
Date: Mon, 13-Apr-87 12:28:28 EST
Article-I.D.: wldrdg.131
Posted: Mon Apr 13 12:28:28 1987
Date-Received: Fri, 17-Apr-87 00:22:57 EST
Organization: Wildridge Consulting,  Boulder, CO
Lines: 56

Having recently installed MINIX on my Zenith 150 I discovered that
I had a read-only hard disk.  When writing, every few blocks would
confuse the driver which would try to reset the disk (a very lengthy
process) and would frequently not write out the block.  After debugging
the Zenith BIOS I came up with the following fix which seems to correct
the problem.  Using this fix I have copied all of the MINIX source
to my hard disk and I've recompiled the kernel about a half-dozen
times, all with no errors.  The fix is a new version of routine
`com_out' for the file `kernel/wini.c'.  Just replace `com_out' with
this one, recompile the kernel and the hard disk should work.

Don Dugger
Wildridge Consulting
...nbires!onecom!wldrdg!n0ano

PRIVATE com_out(mode)
int mode;
{
/* Output the command block to the winchester controller and return status */

	register int i = 0;
	int r;

	port_out(WIN_DMA, mode);
	port_out(WIN_SELECT, mode);
	for (i=0; i<300; i++) {
		port_in(WIN_STATUS, &r);
		if (r & 8)
			break;
	}
	if (i == 300) {
		w_need_reset = TRUE;
		return(ERR);
	}
	lock();
	for (i=0; i<6; i++) {
		for (;;) {
			port_in(WIN_STATUS, &r);
			if (r & 1)
				break;
			if ((r & 8) == 0) {
				w_need_reset = TRUE;
				unlock();
				return(ERR);
			}
		}
		if ((r & 0xe) != 0xc) {
			w_need_reset = TRUE;
			unlock();
			return(ERR);
		}
		port_out(WIN_DATA, command[i]);
	}
	unlock();
	return(OK);
}