path: root/drivers/video/geode/lxfb_ops.c

/* Geode LX framebuffer driver
 *
 * Copyright (C) 2006-2007, Advanced Micro Devices,Inc.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.
 */

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/fb.h>
#include <linux/uaccess.h>
#include <linux/delay.h>
#include <asm/geode.h>

#include "lxfb.h"

/* TODO
 * Support panel scaling
 * Add acceleration
 * Add support for interlacing (TV out)
 * Support compression
 */

/* This is the complete list of PLL frequencies that we can set -
 * we will choose the closest match to the incoming clock.
 * freq is the frequency of the dotclock * 1000 (for example,
 * 24823 = 24.983 Mhz).
 * pllval is the corresponding PLL value
*/

static const struct {
  unsigned int pllval;
  unsigned int freq;
} pll_table[] = {
  { 0x000131AC,   6231 },
  { 0x0001215D,   6294 },
  { 0x00011087,   6750 },
  { 0x0001216C,   7081 },
  { 0x0001218D,   7140 },
  { 0x000110C9,   7800 },
  { 0x00013147,   7875 },
  { 0x000110A7,   8258 },
  { 0x00012159,   8778 },
  { 0x00014249,   8875 },
  { 0x00010057,   9000 },
  { 0x0001219A,   9472 },
  { 0x00012158,   9792 },
  { 0x00010045,  10000 },
  { 0x00010089,  10791 },
  { 0x000110E7,  11225 },
  { 0x00012136,  11430 },
  { 0x00013207,  12375 },
  { 0x00012187,  12500 },
  { 0x00014286,  14063 },
  { 0x000110E5,  15016 },
  { 0x00014214,  16250 },
  { 0x00011105,  17045 },
  { 0x000131E4,  18563 },
  { 0x00013183,  18750 },
  { 0x00014284,  19688 },
  { 0x00011104,  20400 },
  { 0x00016363,  23625 },
  { 0x000031AC,  24923 },
  { 0x0000215D,  25175 },
  { 0x00001087,  27000 },
  { 0x0000216C,  28322 },
  { 0x0000218D,  28560 },
  { 0x000010C9,  31200 },
  { 0x00003147,  31500 },
  { 0x000010A7,  33032 },
  { 0x00002159,  35112 },
  { 0x00004249,  35500 },
  { 0x00000057,  36000 },
  { 0x0000219A,  37889 },
  { 0x00002158,  39168 },
  { 0x00000045,  40000 },
  { 0x00000089,  43163 },
  { 0x000010E7,  44900 },
  { 0x00002136,  45720 },
  { 0x00003207,  49500 },
  { 0x00002187,  50000 },
  { 0x00004286,  56250 },
  { 0x000010E5,  60065 },
  { 0x00004214,  65000 },
  { 0x00001105,  68179 },
  { 0x000031E4,  74250 },
  { 0x00003183,  75000 },
  { 0x00004284,  78750 },
  { 0x00001104,  81600 },
  { 0x00006363,  94500 },
  { 0x00005303,  97520 },
  { 0x00002183, 100187 },
  { 0x00002122, 101420 },
  { 0x00001081, 108000 },
  { 0x00006201, 113310 },
  { 0x00000041, 119650 },
  { 0x000041A1, 129600 },
  { 0x00002182, 133500 },
  { 0x000041B1, 135000 },
  { 0x00000051, 144000 },
  { 0x000041E1, 148500 },
  { 0x000062D1, 157500 },
  { 0x000031A1, 162000 },
  { 0x00000061, 169203 },
  { 0x00004231, 172800 },
  { 0x00002151, 175500 },
  { 0x000052E1, 189000 },
  { 0x00000071, 192000 },
  { 0x00003201, 198000 },
  { 0x00004291, 202500 },
  { 0x00001101, 204750 },
  { 0x00007481, 218250 },
  { 0x00004170, 229500 },
  { 0x00006210, 234000 },
  { 0x00003140, 251182 },
  { 0x00006250, 261000 },
  { 0x000041C0, 278400 },
  { 0x00005220, 280640 },
  { 0x00000050, 288000 },
  { 0x000041E0, 297000 },
  { 0x00002130, 320207 }
};


static void lx_set_dotpll(u32 pllval)
{
	u32 dotpll_lo, dotpll_hi;
	int i;

	rdmsr(MSR_GLCP_DOTPLL, dotpll_lo, dotpll_hi);

	if ((dotpll_lo & MSR_GLCP_DOTPLL_LOCK) && (dotpll_hi == pllval))
		return;

	dotpll_hi = pllval;
	dotpll_lo &= ~(MSR_GLCP_DOTPLL_BYPASS | MSR_GLCP_DOTPLL_HALFPIX);
	dotpll_lo |= MSR_GLCP_DOTPLL_DOTRESET;

	wrmsr(MSR_GLCP_DOTPLL, dotpll_lo, dotpll_hi);

	/* Wait 100us for the PLL to lock */

	udelay(100);

	/* Now, loop for the lock bit */

	for (i = 0; i < 1000; i++) {
		rdmsr(MSR_GLCP_DOTPLL, dotpll_lo, dotpll_hi);
		if (dotpll_lo & MSR_GLCP_DOTPLL_LOCK)
			break;
	}

	/* Clear the reset bit */

	dotpll_lo &= ~MSR_GLCP_DOTPLL_DOTRESET;
	wrmsr(MSR_GLCP_DOTPLL, dotpll_lo, dotpll_hi);
}

/* Set the clock based on the frequency specified by the current mode */

static void lx_set_clock(struct fb_info *info)
{
	unsigned int diff, min, best = 0;
	uns