pvr2fb.c

Linux环境下视频显示卡设备的驱动程序源代码

/*
 * drivers/video/pvr2fb.c
 *
 * Frame buffer and fbcon support for the NEC PowerVR2 found within the Sega
 * Dreamcast.
 *
 * Copyright (c) 2001 M. R. Brown <[e-mail]>
 * Copyright (c) 2001 - 2008  Paul Mundt <[e-mail]>
 *
 * This driver is mostly based on the excellent amifb and vfb sources.  It uses
 * an odd scheme for converting hardware values to/from framebuffer values,
 * here are some hacked-up formulas:
 *
 *  The Dreamcast has screen offsets from each side of its four borders and
 *  the start offsets of the display window.  I used these values to calculate
 *  'pseudo' values (think of them as placeholders) for the fb video mode, so
 *  that when it came time to convert these values back into their hardware
 *  values, I could just add mode- specific offsets to get the correct mode
 *  settings:
 *
 *      left_margin = diwstart_h - borderstart_h;
 *      right_margin = borderstop_h - (diwstart_h + xres);
 *      upper_margin = diwstart_v - borderstart_v;
 *      lower_margin = borderstop_v - (diwstart_h + yres);
 *
 *      hsync_len = borderstart_h + (hsync_total - borderstop_h);
 *      vsync_len = borderstart_v + (vsync_total - borderstop_v);
 *
 *  Then, when it's time to convert back to hardware settings, the only
 *  constants are the borderstart_* offsets, all other values are derived from
 *  the fb video mode:
 *
 *      // PAL
 *      borderstart_h = 116;
 *      borderstart_v = 44;
 *      ...
 *      borderstop_h = borderstart_h + hsync_total - hsync_len;
 *      ...
 *      diwstart_v = borderstart_v - upper_margin;
 *
 *  However, in the current implementation, the borderstart values haven't had
 *  the benefit of being fully researched, so some modes may be broken.
 */

#undef DEBUG

#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/interrupt.h>
#include <linux/fb.h>
#include <linux/init.h>
#include <linux/pci.h>

#ifdef CONFIG_SH_DREAMCAST
#include <asm/machvec.h>
#include <mach-dreamcast/mach/sysasic.h>
#endif

#ifdef CONFIG_SH_DMA
#include <linux/pagemap.h>
#include <mach/dma.h>
#include <asm/dma.h>
#endif

#ifdef CONFIG_SH_STORE_QUEUES
#include <linux/uaccess.h>
#include <cpu/sq.h>
#endif

#ifndef PCI_DEVICE_ID_NEC_NEON250
#  define PCI_DEVICE_ID_NEC_NEON250	0x0067
#endif

/* 2D video registers */
#define DISP_BASE	par->mmio_base
#define DISP_BRDRCOLR (DISP_BASE + 0x40)
#define DISP_DIWMODE (DISP_BASE + 0x44)
#define DISP_DIWADDRL (DISP_BASE + 0x50)
#define DISP_DIWADDRS (DISP_BASE + 0x54)
#define DISP_DIWSIZE (DISP_BASE + 0x5c)
#define DISP_SYNCCONF (DISP_BASE + 0xd0)
#define DISP_BRDRHORZ (DISP_BASE + 0xd4)
#define DISP_SYNCSIZE (DISP_BASE + 0xd8)
#define DISP_BRDRVERT (DISP_BASE + 0xdc)
#define DISP_DIWCONF (DISP_BASE + 0xe8)
#define DISP_DIWHSTRT (DISP_BASE + 0xec)
#define DISP_DIWVSTRT (DISP_BASE + 0xf0)
#define DISP_PIXDEPTH (DISP_BASE + 0x108)

/* Pixel clocks, one for TV output, doubled for VGA output */
#define TV_CLK 74239
#define VGA_CLK 37119

/* This is for 60Hz - the VTOTAL is doubled for interlaced modes */
#define PAL_HTOTAL 863
#define PAL_VTOTAL 312
#define NTSC_HTOTAL 857
#define NTSC_VTOTAL 262

/* Supported cable types */
enum { CT_VGA, CT_NONE, CT_RGB, CT_COMPOSITE };

/* Supported video output types */
enum { VO_PAL, VO_NTSC, VO_VGA };

/* Supported palette types */
enum { PAL_ARGB1555, PAL_RGB565, PAL_ARGB4444, PAL_ARGB8888 };

struct pvr2_params { unsigned int val; char *name; };
static struct pvr2_params cables[] __devinitdata = {
	{ CT_VGA, "VGA" }, { CT_RGB, "RGB" }, { CT_COMPOSITE, "COMPOSITE" },
};

static struct pvr2_params outputs[] __devinitdata = {
	{ VO_PAL, "PAL" }, { VO_NTSC, "NTSC" }, { VO_VGA, "VGA" },
};

/*
 * This describes the current video mode
 */

static struct pvr2fb_par {
	unsigned int hsync_total;	/* Clocks/line */
	unsigned int vsync_total;	/* Lines/field */
	unsigned int borderstart_h;
	unsigned int borderstop_h;
	unsigned int borderstart_v;
	unsigned int borderstop_v;
	unsigned int diwstart_h;	/* Horizontal offset of the display field */
	unsigned int diwstart_v;	/* Vertical offset of the display field, for
				   interlaced modes, this is the long field */
	unsigned long disp_start;	/* Address of image within VRAM */
	unsigned char is_interlaced;	/* Is the display interlaced? */
	unsigned char is_doublescan;	/* Are scanlines output twice? (doublescan) */
	unsigned char is_lowres;	/* Is horizontal pixel-doubling enabled? */

	unsigned long mmio_base;	/* MMIO base */
	u32 palette[16];
} *currentpar;

static struct fb_info *fb_info;

static struct fb_fix_screeninfo pvr2_fix __devinitdata = {
	.id =		"NEC PowerVR2",
	.type =		FB_TYPE_PACKED_PIXELS,
	.visual =	FB_VISUAL_TRUECOLOR,
	.ypanstep =	1,
	.ywrapstep =	1,
	.accel =	FB_ACCEL_NONE,
};

static struct fb_var_screeninfo pvr2_var __devinitdata = {
	.xres =		640,
	.yres =		480,
	.xres_virtual =	640,
	.yres_virtual = 480,
	.bits_per_pixel	=16,
	.red =		{ 11, 5, 0 },
	.green =	{  5, 6, 0 },
	.blue =		{  0, 5, 0 },
	.activate =	FB_ACTIVATE_NOW,
	.height =	-1,
	.width =	-1,
	.vmode =	FB_VMODE_NONINTERLACED,
};

static int cable_type = CT_VGA;
static int video_output = VO_VGA;

static int nopan = 0;
static int nowrap = 1;

/*
 * We do all updating, blanking, etc. during the vertical retrace period
 */
static unsigned int do_vmode_full = 0;	/* Change the video mode */
static unsigned int do_vmode_pan = 0;	/* Update the video mode */
static short do_blank = 0;		/* (Un)Blank the screen */

static unsigned int is_blanked = 0;		/* Is the screen blanked? */

#ifdef CONFIG_SH_STORE_QUEUES
static unsigned long pvr2fb_map;
#endif

#ifdef CONFIG_SH_DMA
static unsigned int shdma = PVR2_CASCADE_CHAN;
static unsigned int pvr2dma = ONCHIP_NR_DMA_CHANNELS;
#endif

static int pvr2fb_setcolreg(unsigned int regno, unsigned int red, unsigned int green, unsigned int blue,
                            unsigned int transp, struct fb_info *info);
static int pvr2fb_blank(int blank, struct fb_info *info);
static unsigned long get_line_length(int xres_virtual, int bpp);
static void set_color_bitfields(struct fb_var_screeninfo *var);
static int pvr2fb_check_var(struct fb_var_screeninfo *var, struct fb_info *info);
static int pvr2fb_set_par(struct fb_info *info);
static void pvr2_update_display(struct fb_info *info);
static void pvr2_init_display(struct fb_info *info);
static void pvr2_do_blank(void);
static irqreturn_t pvr2fb_interrupt(int irq, void *dev_id);
static int pvr2_init_cable(void);
static int pvr2_get_param(const struct pvr2_params *p, const char *s,
                            int val, int size);
#ifdef CONFIG_SH_DMA
static ssize_t pvr2fb_write(struct fb_info *info, const char *buf,
			    size_t count, loff_t *ppos);
#endif

static struct fb_ops pvr2fb_ops = {
	.owner		= THIS_MODULE,
	.fb_setcolreg	= pvr2fb_setcolreg,
	.fb_blank	= pvr2fb_blank,
	.fb_check_var	= pvr2fb_check_var,
	.fb_set_par	= pvr2fb_set_par,
#ifdef CONFIG_SH_DMA
	.fb_write	= pvr2fb_write,
#endif
	.fb_fillrect	= cfb_fillrect,
	.fb_copyarea	= cfb_copyarea,
	.fb_imageblit	= cfb_imageblit,
};

static struct fb_videomode pvr2_modedb[] __devinitdata = {
    /*
     * Broadcast video modes (PAL and NTSC).  I'm unfamiliar with
     * PAL-M and PAL-N, but from what I've read both modes parallel PAL and
     * NTSC, so it shouldn't be a problem (I hope).
     */

    {
	/* 640x480 @ 60Hz interlaced (NTSC) */
	"ntsc_640x480i", 60, 640, 480, TV_CLK, 38, 33, 0, 18, 146, 26,
	FB_SYNC_BROADCAST, FB_VMODE_INTERLACED | FB_VMODE_YWRAP
    }, {
	/* 640x240 @ 60Hz (NTSC) */
	/* XXX: Broken! Don't use... */
	"ntsc_640x240", 60, 640, 240, TV_CLK, 38, 33, 0, 0, 146, 22,
	FB_SYNC_BROADCAST, FB_VMODE_YWRAP
    }, {
	/* 640x480 @ 60hz (VGA) */
	"vga_640x480", 60, 640, 480, VGA_CLK, 38, 33, 0, 18, 146, 26,
	0, FB_VMODE_YWRAP
    },
};

#define NUM_TOTAL_MODES  ARRAY_SIZE(pvr2_modedb)

#define DEFMODE_NTSC	0
#define DEFMODE_PAL	0
#define DEFMODE_VGA	2

static int defmode = DEFMODE_NTSC;
static char *mode_option __devinitdata = NULL;

static inline void pvr2fb_set_pal_type(unsigned int type)
{
	struct pvr2fb_par *par = (struct pvr2fb_par *)fb_info->par;

	fb_writel(type, par->mmio_base + 0x108);
}

static inline void pvr2fb_set_pal_entry(struct pvr2fb_par *par,
					unsigned int regno,
					unsigned int val)
{
	fb_writel(val, par->mmio_base + 0x1000 + (4 * regno));
}

static int pvr2fb_blank(int blank, struct fb_info *info)
{
	do_blank = blank ? blank : -1;
	return 0;
}

static inline unsigned long get_line_length(int xres_virtual, int bpp)
{
	return (unsigned long)((((xres_virtual*bpp)+31)&~31) >> 3);
}

static void set_color_bitfields(struct fb_var_screeninfo *var)
{
	switch (var->bits_per_pixel) {
	    case 16:        /* RGB 565 */
		pvr2fb_set_pal_type(PAL_RGB565);
		var->red.offset = 11;    var->red.length = 5;
		var->green.offset = 5;   var->green.length = 6;
		var->blue.offset = 0;    var->blue.length = 5;
		var->transp.offset = 0;  var->transp.length = 0;
		break;
	    case 24:        /* RGB 888 */
		var->red.offset = 16;    var->red.length = 8;
		var->green.offset = 8;   var->green.length = 8;
		var->blue.offset = 0;    var->blue.length = 8;
		var->transp.offset = 0;  var->transp.length = 0;
		break;
	    case 32:        /* ARGB 8888 */
		pvr2fb_set_pal_type(PAL_ARGB8888);
		var->red.offset = 16;    var->red.length = 8;
		var->green.offset = 8;   var->green.length = 8;
		var->blue.offset = 0;    var->blue.length = 8;
		var->transp.offset = 24; var->transp.length = 8;
		break;
	}
}

static int pvr2fb_setcolreg(unsigned int regno, unsigned int red,
			    unsigned int green, unsigned int blue,
                            unsigned int transp, struct fb_info *info)
{
	struct pvr2fb_par *par = (struct pvr2fb_par *)info->par;
	unsigned int tmp;

	if (regno > info->cmap.len)
		return 1;

	/*
	 * We only support the hardware palette for 16 and 32bpp. It's also
	 * expected that the palette format has been set by the time we get
	 * here, so we don't waste time setting it again.
	 */
	switch (info->var.bits_per_pixel) {
	    case 16: /* RGB 565 */
		tmp =  (red   & 0xf800)       |
		      ((green & 0xfc00) >> 5) |
		      ((blue  & 0xf800) >> 11);

		pvr2fb_set_pal_entry(par, regno, tmp);
		break;
	    case 24: /* RGB 888 */
		red >>= 8; green >>= 8; blue >>= 8;
		tmp = (red << 16) | (green << 8) | blue;
		break;
	    case 32: /* ARGB 8888 */
		red >>= 8; green >>= 8; blue >>= 8;
		tmp = (transp << 24) | (red << 16) | (green << 8) | blue;

		pvr2fb_set_pal_entry(par, regno, tmp);
		break;
	    default:
		pr_debug("Invalid bit depth %d?!?\n", info->var.bits_per_pixel);
		return 1;
	}

	if (regno < 16)
		((u32*)(info->pseudo_palette))[regno] = tmp;

	return 0;
}

static int pvr2fb_set_par(struct fb_info *info)
{
	struct pvr2fb_par *par = (struct pvr2fb_par *)info->par;
	struct fb_var_screeninfo *var = &info->var;
	unsigned long line_length;
	unsigned int vtotal;

	/*
	 * XXX: It's possible that a user could use a VGA box, change the cable
	 * type in hardware (i.e. switch from VGA<->composite), then change
	 * modes (i.e. switching to another VT).  If that happens we should
	 * automagically change the output format to cope, but currently I
	 * don't have a VGA box to make sure this works properly.
	 */
	cable_type = pvr2_init_cable();
	if (cable_type == CT_VGA && video_output != VO_VGA)
		video_output = VO_VGA;

	var->vmode &= FB_VMODE_MASK;
	if (var->vmode & FB_VMODE_INTERLACED && video_output != VO_VGA)
		par->is_interlaced = 1;
	/*
	 * XXX: Need to be more creative with this (i.e. allow doublecan for
	 * PAL/NTSC output).
	 */
	if (var->vmode & FB_VMODE_DOUBLE && video_output == VO_VGA)