Home | History | Annotate | Line # | Download | only in dev
videopll.c revision 1.1.10.1
      1  1.1.10.1  jdolecek /*	$NetBSD: videopll.c,v 1.1.10.1 2017/12/03 11:36:25 jdolecek Exp $	*/
      2       1.1  macallan 
      3       1.1  macallan /*
      4       1.1  macallan  * Copyright (c) 2012 Michael Lorenz
      5       1.1  macallan  * All rights reserved.
      6       1.1  macallan  *
      7       1.1  macallan  * Redistribution and use in source and binary forms, with or without
      8       1.1  macallan  * modification, are permitted provided that the following conditions
      9       1.1  macallan  * are met:
     10       1.1  macallan  * 1. Redistributions of source code must retain the above copyright
     11       1.1  macallan  *    notice, this list of conditions and the following disclaimer.
     12       1.1  macallan  * 2. Redistributions in binary form must reproduce the above copyright
     13       1.1  macallan  *    notice, this list of conditions and the following disclaimer in the
     14       1.1  macallan  *    documentation and/or other materials provided with the distribution.
     15       1.1  macallan  *
     16       1.1  macallan  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     17       1.1  macallan  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     18       1.1  macallan  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     19       1.1  macallan  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     20       1.1  macallan  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     21       1.1  macallan  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     22       1.1  macallan  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     23       1.1  macallan  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     24       1.1  macallan  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     25       1.1  macallan  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     26       1.1  macallan  */
     27       1.1  macallan 
     28       1.1  macallan /*
     29       1.1  macallan  * A driver for the iic-controlled PLLs used in early Apple onboard video
     30  1.1.10.1  jdolecek  * hardware. For now we support /valkyrie only but others use very similar
     31       1.1  macallan  * schemes to program their pixel clock so adding support for those should
     32       1.1  macallan  * be simple enough.
     33       1.1  macallan  */
     34       1.1  macallan 
     35       1.1  macallan #include <sys/cdefs.h>
     36  1.1.10.1  jdolecek __KERNEL_RCSID(0, "$NetBSD: videopll.c,v 1.1.10.1 2017/12/03 11:36:25 jdolecek Exp $");
     37       1.1  macallan 
     38       1.1  macallan #include <sys/param.h>
     39       1.1  macallan #include <sys/systm.h>
     40       1.1  macallan #include <sys/kernel.h>
     41       1.1  macallan #include <sys/device.h>
     42       1.1  macallan #include <sys/malloc.h>
     43       1.1  macallan 
     44       1.1  macallan #include <dev/ofw/openfirm.h>
     45       1.1  macallan #include <dev/i2c/i2cvar.h>
     46       1.1  macallan #include <arch/macppc/dev/videopllvar.h>
     47       1.1  macallan 
     48       1.1  macallan #include "opt_videopll.h"
     49       1.1  macallan #ifdef VIDEOPLL_DEBUG
     50       1.1  macallan #define DPRINTF printf
     51       1.1  macallan #else
     52       1.1  macallan #define DPRINTF while (0) printf
     53       1.1  macallan #endif
     54       1.1  macallan 
     55       1.1  macallan struct videopll_softc {
     56       1.1  macallan 	device_t sc_dev;
     57       1.1  macallan 	i2c_tag_t sc_tag;
     58       1.1  macallan 	int sc_addr;
     59       1.1  macallan };
     60       1.1  macallan 
     61       1.1  macallan static int  videopll_match(device_t, cfdata_t, void *);
     62       1.1  macallan static void videopll_attach(device_t, device_t, void *);
     63       1.1  macallan 
     64       1.1  macallan CFATTACH_DECL_NEW(videopll, sizeof(struct videopll_softc),
     65       1.1  macallan 	videopll_match, videopll_attach, NULL, NULL);
     66       1.1  macallan 
     67       1.1  macallan static void *glob = NULL;
     68       1.1  macallan 
     69       1.1  macallan static int
     70       1.1  macallan videopll_match(device_t parent, cfdata_t cfdata, void *aux)
     71       1.1  macallan {
     72       1.1  macallan 	struct i2c_attach_args *ia = aux;
     73       1.1  macallan 
     74  1.1.10.1  jdolecek 	if (strcmp(ia->ia_name, "videopll") == 0)
     75       1.1  macallan 		return 100;
     76  1.1.10.1  jdolecek 
     77       1.1  macallan 	return 0;
     78       1.1  macallan }
     79       1.1  macallan 
     80       1.1  macallan static void
     81       1.1  macallan videopll_attach(device_t parent, device_t self, void *aux)
     82       1.1  macallan {
     83       1.1  macallan 	struct i2c_attach_args *ia = aux;
     84       1.1  macallan 	struct videopll_softc *sc = device_private(self);
     85       1.1  macallan 
     86       1.1  macallan 	sc->sc_dev = self;
     87       1.1  macallan 	sc->sc_tag = ia->ia_tag;
     88       1.1  macallan 	sc->sc_addr = ia->ia_addr;
     89       1.1  macallan 	aprint_normal(": Apple onboard video PLL\n");
     90       1.1  macallan 	glob = sc;
     91       1.1  macallan }
     92       1.1  macallan 
     93       1.1  macallan /*
     94       1.1  macallan  * pixel clock:
     95       1.1  macallan  * 3.9064MHz * 2^p2 * p1 / p0
     96       1.1  macallan  */
     97       1.1  macallan int
     98       1.1  macallan videopll_set_freq(int freq)
     99       1.1  macallan {
    100       1.1  macallan 	struct videopll_softc *sc = glob;
    101       1.1  macallan 	int p0, p1, p2;
    102       1.1  macallan 	int freq_out, diff, diff_b = 100000000;
    103       1.1  macallan 	int b0 = 0, b1 = 0, b2 = 0, freq_b = 0;
    104       1.1  macallan 	uint8_t cmdbuf[4];
    105       1.1  macallan 
    106       1.1  macallan 	if (glob == NULL)
    107       1.1  macallan 		return EIO;
    108       1.1  macallan 	/*
    109       1.1  macallan 	 * XXX
    110       1.1  macallan 	 * The parameter ranges were taken from Linux' valkyriefb.c mode list.
    111       1.1  macallan 	 * We don't really know what exact parameters the PLL supports but
    112       1.1  macallan 	 * this should be enough for the modes we can actually support
    113       1.1  macallan 	 */
    114       1.1  macallan 	for (p2 = 2; p2 < 4; p2++) {
    115       1.1  macallan 		for (p1 = 27; p1 < 43; p1++) {
    116       1.1  macallan 			for (p0 = 11; p0 < 26; p0++) {
    117       1.1  macallan 				freq_out = (3906400 * (1 << p2) * p1) / (p0 * 1000);
    118       1.1  macallan 				diff = abs(freq - freq_out);
    119       1.1  macallan 				if (diff < diff_b) {
    120       1.1  macallan 					diff_b = diff;
    121       1.1  macallan 					b0 = p0;
    122       1.1  macallan 					b1 = p1;
    123       1.1  macallan 					b2 = p2;
    124       1.1  macallan 					freq_b = freq_out;
    125       1.1  macallan 				}
    126       1.1  macallan 			}
    127       1.1  macallan 		}
    128       1.1  macallan 	}
    129       1.1  macallan 	if (freq_b == 0)
    130       1.1  macallan 		return EINVAL;
    131       1.1  macallan 	DPRINTF("param: %d %d %d -> %d\n", b0, b1, b2, freq_b);
    132       1.1  macallan 	iic_acquire_bus(sc->sc_tag, 0);
    133       1.1  macallan 	cmdbuf[0] = 1;
    134       1.1  macallan 	cmdbuf[1] = b0;
    135       1.1  macallan 	iic_exec(sc->sc_tag, I2C_OP_WRITE,
    136       1.1  macallan 	    sc->sc_addr, cmdbuf, 2, NULL, 0, 0);
    137       1.1  macallan 	cmdbuf[0] = 2;
    138       1.1  macallan 	cmdbuf[1] = b1;
    139       1.1  macallan 	iic_exec(sc->sc_tag, I2C_OP_WRITE,
    140       1.1  macallan 	    sc->sc_addr, cmdbuf, 2, NULL, 0, 0);
    141       1.1  macallan 	cmdbuf[0] = 3;
    142       1.1  macallan 	cmdbuf[1] = b2;
    143       1.1  macallan 	iic_exec(sc->sc_tag, I2C_OP_WRITE,
    144       1.1  macallan 	    sc->sc_addr, cmdbuf, 2, NULL, 0, 0);
    145       1.1  macallan 	iic_release_bus(sc->sc_tag, 0);
    146       1.1  macallan 	return 0;
    147       1.1  macallan }
    148       1.1  macallan 
    149       1.1  macallan 
    150       1.1  macallan 
    151