neofb.c

Linux环境下视频显示卡设备的驱动程序源代码

/*
 * linux/drivers/video/neofb.c -- NeoMagic Framebuffer Driver
 *
 * Copyright (c) 2001-2002  Denis Oliver Kropp <[e-mail]>
 *
 *
 * Card specific code is based on XFree86's neomagic driver.
 * Framebuffer framework code is based on code of cyber2000fb.
 *
 * This file is subject to the terms and conditions of the GNU General
 * Public License.  See the file COPYING in the main directory of this
 * archive for more details.
 *
 *
 * 0.4.1
 *  - Cosmetic changes (dok)
 *
 * 0.4
 *  - Toshiba Libretto support, allow modes larger than LCD size if
 *    LCD is disabled, keep BIOS settings if internal/external display
 *    haven't been enabled explicitly
 *                          (Thomas J. Moore <[e-mail]>)
 *
 * 0.3.3
 *  - Porting over to new fbdev api. (jsimmons)
 *  
 * 0.3.2
 *  - got rid of all floating point (dok) 
 *
 * 0.3.1
 *  - added module license (dok)
 *
 * 0.3
 *  - hardware accelerated clear and move for 2200 and above (dok)
 *  - maximum allowed dotclock is handled now (dok)
 *
 * 0.2.1
 *  - correct panning after X usage (dok)
 *  - added module and kernel parameters (dok)
 *  - no stretching if external display is enabled (dok)
 *
 * 0.2
 *  - initial version (dok)
 *
 *
 * TODO
 * - ioctl for internal/external switching
 * - blanking
 * - 32bit depth support, maybe impossible
 * - disable pan-on-sync, need specs
 *
 * BUGS
 * - white margin on bootup like with tdfxfb (colormap problem?)
 *
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/fb.h>
#include <linux/pci.h>
#include <linux/init.h>
#ifdef CONFIG_TOSHIBA
#include <linux/toshiba.h>
#endif

#include <asm/io.h>
#include <asm/irq.h>
#include <asm/pgtable.h>
#include <asm/system.h>

#ifdef CONFIG_MTRR
#include <asm/mtrr.h>
#endif

#include <video/vga.h>
#include <video/neomagic.h>

#define NEOFB_VERSION "0.4.2"

/* --------------------------------------------------------------------- */

static int internal;
static int external;
static int libretto;
static int nostretch;
static int nopciburst;
static char *mode_option __devinitdata = NULL;

#ifdef MODULE

MODULE_AUTHOR("(c) 2001-2002  Denis Oliver Kropp <[e-mail]>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("FBDev driver for NeoMagic PCI Chips");
module_param(internal, bool, 0);
MODULE_PARM_DESC(internal, "Enable output on internal LCD Display.");
module_param(external, bool, 0);
MODULE_PARM_DESC(external, "Enable output on external CRT.");
module_param(libretto, bool, 0);
MODULE_PARM_DESC(libretto, "Force Libretto 100/110 800x480 LCD.");
module_param(nostretch, bool, 0);
MODULE_PARM_DESC(nostretch,
		 "Disable stretching of modes smaller than LCD.");
module_param(nopciburst, bool, 0);
MODULE_PARM_DESC(nopciburst, "Disable PCI burst mode.");
module_param(mode_option, charp, 0);
MODULE_PARM_DESC(mode_option, "Preferred video mode ('640x480-8@60', etc)");

#endif


/* --------------------------------------------------------------------- */

static biosMode bios8[] = {
	{320, 240, 0x40},
	{300, 400, 0x42},
	{640, 400, 0x20},
	{640, 480, 0x21},
	{800, 600, 0x23},
	{1024, 768, 0x25},
};

static biosMode bios16[] = {
	{320, 200, 0x2e},
	{320, 240, 0x41},
	{300, 400, 0x43},
	{640, 480, 0x31},
	{800, 600, 0x34},
	{1024, 768, 0x37},
};

static biosMode bios24[] = {
	{640, 480, 0x32},
	{800, 600, 0x35},
	{1024, 768, 0x38}
};

#ifdef NO_32BIT_SUPPORT_YET
/* FIXME: guessed values, wrong */
static biosMode bios32[] = {
	{640, 480, 0x33},
	{800, 600, 0x36},
	{1024, 768, 0x39}
};
#endif

static inline void write_le32(int regindex, u32 val, const struct neofb_par *par)
{
	writel(val, par->neo2200 + par->cursorOff + regindex);
}

static int neoFindMode(int xres, int yres, int depth)
{
	int xres_s;
	int i, size;
	biosMode *mode;

	switch (depth) {
	case 8:
		size = ARRAY_SIZE(bios8);
		mode = bios8;
		break;
	case 16:
		size = ARRAY_SIZE(bios16);
		mode = bios16;
		break;
	case 24:
		size = ARRAY_SIZE(bios24);
		mode = bios24;
		break;
#ifdef NO_32BIT_SUPPORT_YET
	case 32:
		size = ARRAY_SIZE(bios32);
		mode = bios32;
		break;
#endif
	default:
		return 0;
	}

	for (i = 0; i < size; i++) {
		if (xres <= mode[i].x_res) {
			xres_s = mode[i].x_res;
			for (; i < size; i++) {
				if (mode[i].x_res != xres_s)
					return mode[i - 1].mode;
				if (yres <= mode[i].y_res)
					return mode[i].mode;
			}
		}
	}
	return mode[size - 1].mode;
}

/*
 * neoCalcVCLK --
 *
 * Determine the closest clock frequency to the one requested.
 */
#define MAX_N 127
#define MAX_D 31
#define MAX_F 1

static void neoCalcVCLK(const struct fb_info *info,
			struct neofb_par *par, long freq)
{
	int n, d, f;
	int n_best = 0, d_best = 0, f_best = 0;
	long f_best_diff = 0x7ffff;

	for (f = 0; f <= MAX_F; f++)
		for (d = 0; d <= MAX_D; d++)
			for (n = 0; n <= MAX_N; n++) {
				long f_out;
				long f_diff;

				f_out = ((14318 * (n + 1)) / (d + 1)) >> f;
				f_diff = abs(f_out - freq);
				if (f_diff <= f_best_diff) {
					f_best_diff = f_diff;
					n_best = n;
					d_best = d;
					f_best = f;
				}
				if (f_out > freq)
					break;
			}

	if (info->fix.accel == FB_ACCEL_NEOMAGIC_NM2200 ||
	    info->fix.accel == FB_ACCEL_NEOMAGIC_NM2230 ||
	    info->fix.accel == FB_ACCEL_NEOMAGIC_NM2360 ||
	    info->fix.accel == FB_ACCEL_NEOMAGIC_NM2380) {
		/* NOT_DONE:  We are trying the full range of the 2200 clock.
		   We should be able to try n up to 2047 */
		par->VCLK3NumeratorLow = n_best;
		par->VCLK3NumeratorHigh = (f_best << 7);
	} else
		par->VCLK3NumeratorLow = n_best | (f_best << 7);

	par->VCLK3Denominator = d_best;

#ifdef NEOFB_DEBUG
	printk(KERN_DEBUG "neoVCLK: f:%ld NumLow=%d NumHi=%d Den=%d Df=%ld\n",
	       freq,
	       par->VCLK3NumeratorLow,
	       par->VCLK3NumeratorHigh,
	       par->VCLK3Denominator, f_best_diff);
#endif
}

/*
 * vgaHWInit --
 *      Handle the initialization, etc. of a screen.
 *      Return FALSE on failure.
 */

static int vgaHWInit(const struct fb_var_screeninfo *var,
		     struct neofb_par *par)
{
	int hsync_end = var->xres + var->right_margin + var->hsync_len;
	int htotal = (hsync_end + var->left_margin) >> 3;
	int vsync_start = var->yres + var->lower_margin;
	int vsync_end = vsync_start + var->vsync_len;
	int vtotal = vsync_end + var->upper_margin;

	par->MiscOutReg = 0x23;

	if (!(var->sync & FB_SYNC_HOR_HIGH_ACT))
		par->MiscOutReg |= 0x40;

	if (!(var->sync & FB_SYNC_VERT_HIGH_ACT))
		par->MiscOutReg |= 0x80;

	/*
	 * Time Sequencer
	 */
	par->Sequencer[0] = 0x00;
	par->Sequencer[1] = 0x01;
	par->Sequencer[2] = 0x0F;
	par->Sequencer[3] = 0x00;	/* Font select */
	par->Sequencer[4] = 0x0E;	/* Misc */

	/*
	 * CRTC Controller
	 */
	par->CRTC[0] = htotal - 5;
	par->CRTC[1] = (var->xres >> 3) - 1;
	par->CRTC[2] = (var->xres >> 3) - 1;
	par->CRTC[3] = ((htotal - 1) & 0x1F) | 0x80;
	par->CRTC[4] = ((var->xres + var->right_margin) >> 3);
	par->CRTC[5] = (((htotal - 1) & 0x20) << 2)
	    | (((hsync_end >> 3)) & 0x1F);
	par->CRTC[6] = (vtotal - 2) & 0xFF;
	par->CRTC[7] = (((vtotal - 2) & 0x100) >> 8)
	    | (((var->yres - 1) & 0x100) >> 7)
	    | ((vsync_start & 0x100) >> 6)
	    | (((var->yres - 1) & 0x100) >> 5)
	    | 0x10 | (((vtotal - 2) & 0x200) >> 4)
	    | (((var->yres - 1) & 0x200) >> 3)
	    | ((vsync_start & 0x200) >> 2);
	par->CRTC[8] = 0x00;
	par->CRTC[9] = (((var->yres - 1) & 0x200) >> 4) | 0x40;

	if (var->vmode & FB_VMODE_DOUBLE)
		par->CRTC[9] |= 0x80;

	par->CRTC[10] = 0x00;
	par->CRTC[11] = 0x00;
	par->CRTC[12] = 0x00;
	par->CRTC[13] = 0x00;
	par->CRTC[14] = 0x00;
	par->CRTC[15] = 0x00;
	par->CRTC[16] = vsync_start & 0xFF;
	par->CRTC[17] = (vsync_end & 0x0F) | 0x20;
	par->CRTC[18] = (var->yres - 1) & 0xFF;
	par->CRTC[19] = var->xres_virtual >> 4;
	par->CRTC[20] = 0x00;
	par->CRTC[21] = (var->yres - 1) & 0xFF;
	par->CRTC[22] = (vtotal - 1) & 0xFF;
	par->CRTC[23] = 0xC3;
	par->CRTC[24] = 0xFF;

	/*
	 * are these unnecessary?
	 * vgaHWHBlankKGA(mode, regp, 0, KGA_FIX_OVERSCAN | KGA_ENABLE_ON_ZERO);
	 * vgaHWVBlankKGA(mode, regp, 0, KGA_FIX_OVERSCAN | KGA_ENABLE_ON_ZERO);
	 */

	/*
	 * Graphics Display Controller
	 */
	par->Graphics[0] = 0x00;
	par->Graphics[1] = 0x00;
	par->Graphics[2] = 0x00;
	par->Graphics[3] = 0x00;
	par->Graphics[4] = 0x00;
	par->Graphics[5] = 0x40;
	par->Graphics[6] = 0x05;	/* only map 64k VGA memory !!!! */
	par->Graphics[7] = 0x0F;
	par->Graphics[8] = 0xFF;


	par->Attribute[0] = 0x00;	/* standard colormap translation */
	par->Attribute[1] = 0x01;
	par->Attribute[2] = 0x02;
	par->Attribute[3] = 0x03;
	par->Attribute[4] = 0x04;
	par->Attribute[5] = 0x05;
	par->Attribute[6] = 0x06;
	par->Attribute[7] = 0x07;
	par->Attribute[8] = 0x08;
	par->Attribute[9] = 0x09;
	par->Attribute[10] = 0x0A;
	par->Attribute[11] = 0x0B;
	par->Attribute[12] = 0x0C;
	par->Attribute[13] = 0x0D;
	par->Attribute[14] = 0x0E;
	par->Attribute[15] = 0x0F;
	par->Attribute[16] = 0x41;
	par->Attribute[17] = 0xFF;
	par->Attribute[18] = 0x0F;
	par->Attribute[19] = 0x00;
	par->Attribute[20] = 0x00;
	return 0;
}

static void vgaHWLock(struct vgastate *state)
{
	/* Protect CRTC[0-7] */
	vga_wcrt(state->vgabase, 0x11, vga_rcrt(state->vgabase, 0x11) | 0x80);
}

static void vgaHWUnlock(void)
{
	/* Unprotect CRTC[0-7] */
	vga_wcrt(NULL, 0x11, vga_rcrt(NULL, 0x11) & ~0x80);
}

static void neoLock(struct vgastate *state)
{
	vga_wgfx(state->vgabase, 0x09, 0x00);
	vgaHWLock(state);
}

static void neoUnlock(void)
{
	vgaHWUnlock();
	vga_wgfx(NULL, 0x09, 0x26);
}

/*
 * VGA Palette management
 */
static int paletteEnabled = 0;

static inline void VGAenablePalette(void)
{
	vga_r(NULL, VGA_IS1_RC);
	vga_w(NULL, VGA_ATT_W, 0x00);
	paletteEnabled = 1;
}

static inline void VGAdisablePalette(void)
{
	vga_r(NULL, VGA_IS1_RC);
	vga_w(NULL, VGA_ATT_W, 0x20);
	paletteEnabled = 0;
}

static inline void VGAwATTR(u8 index, u8 value)
{
	if (paletteEnabled)
		index &= ~0x20;
	else
		index |= 0x20;

	vga_r(NULL, VGA_IS1_RC);
	vga_wattr(NULL, index, value);
}

static void vgaHWProtect(int on)
{
	unsigned char tmp;

	tmp = vga_rseq(NULL, 0x01);
	if (on) {
		/*
		 * Turn off screen and disable sequencer.
		 */
		vga_wseq(NULL, 0x00, 0x01);		/* Synchronous Reset */
		vga_wseq(NULL, 0x01, tmp | 0x20);	/* disable the display */

		VGAenablePalette();
	} else {
		/*
		 * Reenable sequencer, then turn on screen.
		 */
		vga_wseq(NULL, 0x01, tmp & ~0x20);	/* reenable display */
		vga_wseq(NULL, 0x00, 0x03);		/* clear synchronousreset */

		VGAdisablePalette();
	}
}

static void vgaHWRestore(const struct fb_info *info,
			 const struct neofb_par *par)
{
	int i;

	vga_w(NULL, VGA_MIS_W, par->MiscOutReg);

	for (i = 1; i < 5; i++)
		vga_wseq(NULL, i, par->Sequencer[i]);

	/* Ensure CRTC registers 0-7 are unlocked by clearing bit 7 or CRTC[17] */
	vga_wcrt(NULL, 17, par->CRTC[17] & ~0x80);

	for (i = 0; i < 25; i++)
		vga_wcrt(NULL, i, par->CRTC[i]);

	for (i = 0; i < 9; i++)
		vga_wgfx(NULL, i, par->Graphics[i]);

	VGAenablePalette();

	for (i = 0; i < 21; i++)
		VGAwATTR(i, par->Attribute[i]);

	VGAdisablePalette();
}


/* -------------------- Hardware specific routines ------------------------- */

/*
 * Hardware Acceleration for Neo2200+
 */
static inline int neo2200_sync(struct fb_info *info)
{
	struct neofb_par *par = info->par;

	while (readl(&par->neo2200->bltStat) & 1)
		cpu_relax();
	return 0;
}

static inline void neo2200_wait_fifo(struct fb_info *info,
				     int requested_fifo_space)
{
	//  ndev->neo.waitfifo_calls++;
	//  ndev->neo.waitfifo_sum += requested_fifo_space;

	/* FIXME: does not work
	   if (neo_fifo_space < requested_fifo_space)
	   {
	   neo_fifo_waitcycles++;

	   while (1)
	   {
	   neo_fifo_space = (neo2200->bltStat >> 8);
	   if (neo_fifo_space >= requested_fifo_space)
	   break;
	   }
	   }
	   else
	   {
	   neo_fifo_cache_hits++;
	   }

	   neo_fifo_space -= requested_fifo_space;
	 */

	neo2200_sync(info);
}

static inline void neo2200_accel_init(struct fb_info *info,
				      struct fb_var_screeninfo *var)
{
	struct neofb_par *par = info->par;
	Neo2200 __iomem *neo2200 = par->neo2200;
	u32 bltMod, pitch;

	neo2200_sync(info);

	switch (var->bits_per_pixel) {
	case 8:
		bltMod = NEO_MODE1_DEPTH8;
		pitch = var->xres_virtual;
		break;
	case 15:
	case 16:
		bltMod = NEO_MODE1_DEPTH16;
		pitch = var->xres_virtual * 2;
		break;
	case 24:
		bltMod = NEO_MODE1_DEPTH24;
		pitch = var->xres_virtual * 3;
		break;
	default:
		printk(KERN_ERR
		       "neofb: neo2200_accel_init: unexpected bits per pixel!\n");
		return;
	}

	writel(bltMod << 16, &neo2200->bltStat);
	writel((pitch << 16) | pitch, &neo2200->pitch);
}

/* --------------------------------------------------------------------- */

static int
neofb_open(struct fb_info *info, int user)
{
	struct neofb_par *par = info->par;

	if (!par->ref_count) {
		memset(&par->state, 0, sizeof(struct vgastate));
		par->state.flags = VGA_SAVE_MODE | VGA_SAVE_FONTS;
		save_vga(&par->state);
	}