File:  [DragonFly] / src / sys / dev / video / ctx / ctx.c
Revision 1.8: download - view: text, annotated - select for diffs
Wed May 19 22:52:53 2004 UTC (10 years, 2 months ago) by dillon
Branches: MAIN
CVS tags: HEAD, DragonFly_Stable, DragonFly_Snap29Sep2004, DragonFly_Snap13Sep2004, DragonFly_RELEASE_1_6_Slip, DragonFly_RELEASE_1_6, DragonFly_RELEASE_1_4_Slip, DragonFly_RELEASE_1_4, DragonFly_RELEASE_1_2_Slip, DragonFly_RELEASE_1_2, DragonFly_1_0_REL, DragonFly_1_0_RC1, DragonFly_1_0A_REL
Device layer rollup commit.

* cdevsw_add() is now required.  cdevsw_add() and cdevsw_remove() may specify
  a mask/match indicating the range of supported minor numbers.  Multiple
  cdevsw_add()'s using the same major number, but distinctly different
  ranges, may be issued.  All devices that failed to call cdevsw_add() before
  now do.

* cdevsw_remove() now automatically marks all devices within its supported
  range as being destroyed.

* vnode->v_rdev is no longer resolved when the vnode is created.  Instead,
  only v_udev (a newly added field) is resolved.  v_rdev is resolved when
  the vnode is opened and cleared on the last close.

* A great deal of code was making rather dubious assumptions with regards
  to the validity of devices associated with vnodes, primarily due to
  the persistence of a device structure due to being indexed by (major, minor)
  instead of by (cdevsw, major, minor).  In particular, if you run a program
  which connects to a USB device and then you pull the USB device and plug
  it back in, the vnode subsystem will continue to believe that the device
  is open when, in fact, it isn't (because it was destroyed and recreated).

  In particular, note that all the VFS mount procedures now check devices
  via v_udev instead of v_rdev prior to calling VOP_OPEN(), since v_rdev
  is NULL prior to the first open.

* The disk layer's device interaction has been rewritten.  The disk layer
  (i.e. the slice and disklabel management layer) no longer overloads
  its data onto the device structure representing the underlying physical
  disk.  Instead, the disk layer uses the new cdevsw_add() functionality
  to register its own cdevsw using the underlying device's major number,
  and simply does NOT register the underlying device's cdevsw.  No
  confusion is created because the device hash is now based on
  (cdevsw,major,minor) rather then (major,minor).

  NOTE: This also means that underlying raw disk devices may use the entire
  device minor number instead of having to reserve the bits used by the disk
  layer, and also means that can we (theoretically) stack a fully
  disklabel-supported 'disk' on top of any block device.

* The new reference counting scheme prevents this by associating a device
  with a cdevsw and disconnecting the device from its cdevsw when the cdevsw
  is removed.  Additionally, all udev2dev() lookups run through the cdevsw
  mask/match and only successfully find devices still associated with an
  active cdevsw.

* Major work on MFS:  MFS no longer shortcuts vnode and device creation.  It
  now creates a real vnode and a real device and implements real open and
  close VOPs.  Additionally, due to the disk layer changes, MFS is no longer
  limited to 255 mounts.  The new limit is 16 million.  Since MFS creates a
  real device node, mount_mfs will now create a real /dev/mfs<PID> device
  that can be read from userland (e.g. so you can dump an MFS filesystem).

* BUF AND DEVICE STRATEGY changes.  The struct buf contains a b_dev field.
  In order to properly handle stacked devices we now require that the b_dev
  field be initialized before the device strategy routine is called.  This
  required some additional work in various VFS implementations.  To enforce
  this requirement, biodone() now sets b_dev to NODEV.  The new disk layer
  will adjust b_dev before forwarding a request to the actual physical
  device.

* A bug in the ISO CD boot sequence which resulted in a panic has been fixed.

Testing by: lots of people, but David Rhodus found the most aggregious bugs.

/*
 * CORTEX-I Frame Grabber driver V1.0
 *
 *	Copyright (C) 1994, Paul S. LaFollette, Jr. This software may be used,
 *	modified, copied, distributed, and sold, in both source and binary form
 *	provided that the above copyright and these terms are retained. Under
 *	no circumstances is the author responsible for the proper functioning
 *	of this software, nor does the author assume any responsibility
 *	for damages incurred with its use.
 *
 * $FreeBSD: src/sys/i386/isa/ctx.c,v 1.36 2000/01/29 16:17:31 peter Exp $
 * $DragonFly: src/sys/dev/video/ctx/ctx.c,v 1.8 2004/05/19 22:52:53 dillon Exp $
 */

/*
 *
 *
 *
 *	Device Driver for CORTEX-I Frame Grabber
 *	Made by ImageNation Corporation
 *	1200 N.E. Keyues Road
 *	Vancouver, WA 98684  (206) 944-9131
 *	(I have no ties to this company, just thought you might want
 *	 to know how to get in touch with them.)
 *
 *	In order to understand this device, you really need to consult the
 *	manual which ImageNation provides when you buy the board. (And
 *	what a pleasure it is to buy something for a PC and actually get
 *	programming information along with it.)  I will limit myself here to
 *	a few comments which are specific to this driver.  See also the file
 *	ctxreg.h for definitions of registers and control bits.
 *
 *	1.  Although the hardware supports low resolution (256 x 256)
 *	    acqusition and display, I have not implemented access to
 *	    these modes in this driver.  There are some fairly quirky
 *	    aspects to the way this board works in low resolution mode,
 *	    and I don't want to deal with them.  Maybe later.
 *
 *	2.  Choosing the base address for the video memory:  This is set
 *	    using a combination of hardware and software, using the left
 *	    most dip switch on the board, and the AB_SELECT bit of control
 *	    port 1, according to the chart below:
 *
 *		Left DIP switch ||	DOWN	|	UP	|
 *		=================================================
 *		 AB_SELECT =  0	||    0xA0000	|    0xB0000	|
 *		-------------------------------------------------
 *		 AB_SELECT = 1 	||    0xD0000	|    0xE0000	|
 *		------------------------------------------------
 *
 *	    When the RAM_ENABLE bit of control port 1 is clear (0), the
 *	    video ram is disconnected from the computer bus.  This makes
 *	    it possible, in principle, to share memory space with other
 *	    devices (such as VGA) which can also disconnect themselves
 *	    from the bus.  It also means that multiple CORTEX-I boards
 *	    can share the same video memory space.  Disconnecting from the
 *	    bus does not affect the video display of the video ram contents,
 *	    so that one needs only set the RAM_ENABLE bit when actually
 *	    reading or writing to memory.  The cost of this is low,
 *	    the benefits to me are great (I need more than one board
 *	    in my machine, and 0xE0000 is the only address choice that
 *	    doesn't conflict with anything) so I adopt this strategy here.
 *
 *	    XXX-Note... this driver has only been tested for the
 *	    XXX base = 0xE0000 case!
 *
 *	3)  There is a deficiency in the documentation from ImageNation, I
 *	    think.  In order to successfully load the lookup table, it is
 *	    necessary to clear SEE_STORED_VIDEO in control port 0 as well as
 *	    setting LUT_LOAD_ENABLE in control port 1.
 *
 *	4)  This driver accesses video memory through read or write operations.
 *	    Other functionality is provided through ioctl's, manifest
 *	    constants for which are defined in ioctl_ctx.h. The ioctl's
 *	    include:
 *			CTX_LIVE	Display live video
 *			CTX_GRAB	Grab a frame of video data
 *			CTX_H_ORGANIZE	Set things up so that sequential read
 *					operations access horizontal lines of
 *					pixels.
 *			CTX_V_ORGANIZE	Set things up so that sequential read
 *					operations access vertical lines of
 *					pixels.
 *			CTX_SET_LUT	Set the lookup table from an array
 *					of 256 unsigned chars passed as the
 *					third parameter to ioctl.
 *			CTX_GET_LUT	Return the current lookup table to
 *					the application as an array of 256
 *					unsigned chars.  Again the third
 *					parameter to the ioctl call.
 *
 *	    Thus,
 *		ioctl(fi, CTX_H_ORGANIZE, 0);
 *		lseek(fi, y*512, SEEK_SET);
 *		read(fi, buffer, 512);
 *
 *	    will fill buffer with 512 pixels (unsigned chars) which represent
 *	    the y-th horizontal line of the image.
 *	    Similarly,
 *		ioctl(fi, CTX_V_ORGANIZE, 0:
 *		lseek(fi, x*512+y, SEEK_SET);
 *		read(fi, buffer, 10);
 *
 *	    will read 10 a vertical line of 10 pixels starting at (x,y).
 *
 *	    Obviously, this sort of ugliness needs to be hidden away from
 *	    the casual user, with an appropriate set of higher level
 *	    functions.
 *
 */

#include "use_ctx.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/conf.h>
#include <sys/uio.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <bus/isa/i386/isa_device.h>
#include "ctxreg.h"
#include <machine/ioctl_ctx.h>
#include <machine/md_var.h>

static int     waitvb(int port);

/* state flags */
#define   OPEN        (0x01)	/* device is open */

#define   UNIT(x) ((x) & 0x07)

static int	ctxprobe (struct isa_device *devp);
static int	ctxattach (struct isa_device *devp);
struct isa_driver ctxdriver = {ctxprobe, ctxattach, "ctx"};

static	d_open_t	ctxopen;
static	d_close_t	ctxclose;
static	d_read_t	ctxread;
static	d_write_t	ctxwrite;
static	d_ioctl_t	ctxioctl;
#define CDEV_MAJOR 40

static struct cdevsw ctx_cdevsw = {
	/* name */	"ctx",
	/* maj */	CDEV_MAJOR,
	/* flags */	0,
	/* port */	NULL,
	/* clone */	NULL,

	/* open */	ctxopen,
	/* close */	ctxclose,
	/* read */	ctxread,
	/* write */	ctxwrite,
	/* ioctl */	ctxioctl,
	/* poll */	nopoll,
	/* mmap */	nommap,
	/* strategy */	nostrategy,
	/* dump */	nodump,
	/* psize */	nopsize
};


#define   LUTSIZE     256	/* buffer size for Look Up Table (LUT) */
#define   PAGESIZE    65536	/* size of one video page, 1/4 of the screen */

/*
 *  Per unit shadow registers (because the dumb hardware is RO)
*/

static struct ctx_soft_registers {
	u_char *lutp;
	u_char  cp0;
	u_char  cp1;
	u_char  flag;
	int     iobase;
	caddr_t maddr;
	int     msize;
}       ctx_sr[NCTX];


static int
ctxprobe(struct isa_device * devp)
{
	int     status;

	if (inb(devp->id_iobase) == 0xff)	/* 0xff only if board absent */
		status = 0;
	else
		status = 1;			/*XXX uses only one port? */
	return (status);
}

static int
ctxattach(struct isa_device * devp)
{
	struct ctx_soft_registers *sr;

	sr = &(ctx_sr[devp->id_unit]);
	sr->cp0 = 0;	/* zero out the shadow registers */
	sr->cp1 = 0;	/* and the open flag.  wait for  */
	sr->flag = 0;	/* open to malloc the LUT space  */
	sr->iobase = devp->id_iobase;
	sr->maddr = devp->id_maddr;
	sr->msize = devp->id_msize;
	cdevsw_add(&ctx_cdevsw, -1, devp->id_unit);
	make_dev(&ctx_cdevsw, devp->id_unit, 0, 0, 0600, 
		"ctx%d", devp->id_unit);
	return (1);
}

static int
ctxopen(dev_t dev, int flags, int fmt, struct thread *td)
{
	struct ctx_soft_registers *sr;
	u_char  unit;
	int     i;

	unit = UNIT(minor(dev));

	/* minor number out of range? */

	if (unit >= NCTX)
		return (ENXIO);
	sr = &(ctx_sr[unit]);

	if (sr->flag != 0)	/* someone has already opened us */
		return (EBUSY);

	/* get space for the LUT buffer */

	sr->lutp = malloc(LUTSIZE, M_DEVBUF, M_WAITOK);
	if (sr->lutp == NULL)
		return (ENOMEM);

	sr->flag = OPEN;

/*
	Set up the shadow registers.  We don't actually write these
	values to the control ports until after we finish loading the
	lookup table.
*/
	sr->cp0 |= SEE_STORED_VIDEO;
	if ((kvtop(sr->maddr) == 0xB0000) || (kvtop(sr->maddr) == 0xE0000))
		sr->cp1 |= AB_SELECT;	/* map to B or E if necessary */
	/* but don't enable RAM	  */
/*
	Set up the lookup table initially so that it is transparent.
*/

	outb(sr->iobase + ctx_cp0, (u_char) 0);
	outb(sr->iobase + ctx_cp1, (u_char) (LUT_LOAD_ENABLE | BLANK_DISPLAY));
	for (i = 0; i < LUTSIZE; i++) {
		outb(sr->iobase + ctx_lutaddr, (u_char) i);
		sr->lutp[i] = (u_char) i;
		outb(sr->iobase + ctx_lutdata, (u_char) sr->lutp[i]);
	}
/*
	Disable LUT loading, and push the data in the shadow
	registers into the control ports.
*/
	outb(sr->iobase + ctx_cp0, sr->cp0);
	outb(sr->iobase + ctx_cp1, sr->cp1);
	return (0);	/* successful open.  All ready to go. */
}

static int
ctxclose(dev_t dev, int flags, int fmt, struct thread *td)
{
	int     unit;

	unit = UNIT(minor(dev));
	ctx_sr[unit].flag = 0;
	free(ctx_sr[unit].lutp, M_DEVBUF);
	ctx_sr[unit].lutp = NULL;
	return (0);
}

static int
ctxwrite(dev_t dev, struct uio * uio, int ioflag)
{
	int     unit, status = 0;
	int     page, count, offset;
	struct ctx_soft_registers *sr;
	u_long	ef;

	unit = UNIT(minor(dev));
	sr = &(ctx_sr[unit]);

	if (uio->uio_offset < 0)
		return (EINVAL);
	if (uio->uio_offset >= 4 * PAGESIZE)
		page = 4;	/* EOF */
	else
		page = (u_int)uio->uio_offset / PAGESIZE;
	offset = (u_int)uio->uio_offset % PAGESIZE;
	count = min(uio->uio_resid, PAGESIZE - offset);
	while ((page >= 0) && (page <= 3) && (count > 0)) {
		sr->cp0 &= ~3;
		sr->cp0 |= page;
		outb(sr->iobase + ctx_cp0, sr->cp0);

/*
	Before doing the uiomove, we need to "connect" the frame buffer
	ram to the machine bus.  This is done here so that we can have
	several different boards installed, all sharing the same memory
	space... each board is only "connected" to the bus when its memory
	is actually being read or written.  All my instincts tell me that
	I should disable interrupts here, so I have done so.
*/

		ef = read_eflags();
		cpu_disable_intr();
		sr->cp1 |= RAM_ENABLE;
		outb(sr->iobase + ctx_cp1, sr->cp1);
		status = uiomove(sr->maddr + offset, count, uio);
		sr->cp1 &= ~RAM_ENABLE;
		outb(sr->iobase + ctx_cp1, sr->cp1);
		write_eflags(ef);

		page = (u_int)uio->uio_offset / PAGESIZE;
		offset = (u_int)uio->uio_offset % PAGESIZE;
		count = min(uio->uio_resid, PAGESIZE - offset);
	}
	if (uio->uio_resid > 0)
		return (ENOSPC);
	else
		return (status);
}

static int
ctxread(dev_t dev, struct uio * uio, int ioflag)
{
	int     unit, status = 0;
	int     page, count, offset;
	struct ctx_soft_registers *sr;
	u_long  ef;

	unit = UNIT(minor(dev));
	sr = &(ctx_sr[unit]);

	if (uio->uio_offset < 0)
		return (EINVAL);
	if (uio->uio_offset >= 4 * PAGESIZE)
		page = 4;	/* EOF */
	else
		page = (u_int)uio->uio_offset / PAGESIZE;
	offset = (u_int)uio->uio_offset % PAGESIZE;
	count = min(uio->uio_resid, PAGESIZE - offset);
	while ((page >= 0) && (page <= 3) && (count > 0)) {
		sr->cp0 &= ~3;
		sr->cp0 |= page;
		outb(sr->iobase + ctx_cp0, sr->cp0);
/*
	Before doing the uiomove, we need to "connect" the frame buffer
	ram to the machine bus.  This is done here so that we can have
	several different boards installed, all sharing the same memory
	space... each board is only "connected" to the bus when its memory
	is actually being read or written.  All my instincts tell me that
	I should disable interrupts here, so I have done so.
*/
		ef = read_eflags();
		cpu_disable_intr();
		sr->cp1 |= RAM_ENABLE;
		outb(sr->iobase + ctx_cp1, sr->cp1);
		status = uiomove(sr->maddr + offset, count, uio);
		sr->cp1 &= ~RAM_ENABLE;
		outb(sr->iobase + ctx_cp1, sr->cp1);
		write_eflags(ef);

		page = (u_int)uio->uio_offset / PAGESIZE;
		offset = (u_int)uio->uio_offset % PAGESIZE;
		count = min(uio->uio_resid, PAGESIZE - offset);
	}
	if (uio->uio_resid > 0)
		return (ENOSPC);
	else
		return (status);
}

static int
ctxioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct thread *td)
{
	int     error;
	int     unit, i;
	struct ctx_soft_registers *sr;

	error = 0;
	unit = UNIT(minor(dev));
	sr = &(ctx_sr[unit]);

	switch (cmd) {
	case CTX_LIVE:
		sr->cp0 &= ~SEE_STORED_VIDEO;
		outb(sr->iobase + ctx_cp0, sr->cp0);
		break;
	case CTX_GRAB:
		sr->cp0 &= ~SEE_STORED_VIDEO;
		outb(sr->iobase + ctx_cp0, sr->cp0);
		sr->cp0 |= ACQUIRE;
		if (waitvb(sr->iobase))	/* wait for vert blank to start
					 * acquire */
			error = ENODEV;
		outb(sr->iobase + ctx_cp0, sr->cp0);
		if (waitvb(sr->iobase))	/* wait for two more to finish acquire */
			error = ENODEV;
		if (waitvb(sr->iobase))
			error = ENODEV;
		sr->cp0 &= ~ACQUIRE;	/* turn off acquire and turn on
					 * display */
		sr->cp0 |= SEE_STORED_VIDEO;
		outb(sr->iobase + ctx_cp0, sr->cp0);
		break;
	case CTX_H_ORGANIZE:
		sr->cp0 &= ~PAGE_ROTATE;
		outb(sr->iobase + ctx_cp0, sr->cp0);
		break;
	case CTX_V_ORGANIZE:
		sr->cp0 |= PAGE_ROTATE;
		outb(sr->iobase + ctx_cp0, sr->cp0);
		break;
	case CTX_SET_LUT:
		bcopy((u_char *) data, sr->lutp, LUTSIZE);
		outb(sr->iobase + ctx_cp0, (u_char) 0);
		outb(sr->iobase + ctx_cp1, (u_char) (LUT_LOAD_ENABLE | BLANK_DISPLAY));
		for (i = 0; i < LUTSIZE; i++) {
			outb(sr->iobase + ctx_lutaddr, i);
			outb(sr->iobase + ctx_lutdata, sr->lutp[i]);
		}
		outb(sr->iobase + ctx_cp0, sr->cp0);	/* restore control
							 * registers */
		outb(sr->iobase + ctx_cp1, sr->cp1);
		break;
	case CTX_GET_LUT:
		bcopy(sr->lutp, (u_char *) data, LUTSIZE);
		break;
	default:
		error = ENODEV;
	}

	return (error);
}

static int
waitvb(int port)
{				/* wait for a vertical blank,  */
	if (inb(port) == 0xff)	/* 0xff means no board present */
		return (1);

	while ((inb(port) & VERTICAL_BLANK) != 0) {
	}
	while ((inb(port) & VERTICAL_BLANK) == 0) {
	}

	return (0);
}