path: root/drivers/video/pvr2fb.c

/*
 * drivers/video/pvr2fb.c
 *
 * Frame buffer and fbcon support for the NEC PowerVR2 found within the Sega
 * Dreamcast.
 *
 * Copyright (c) 2001 M. R. Brown <mrbrown@0xd6.org>
 * Copyright (c) 2001 - 2008  Paul Mundt <lethal@linux-sh.org>
 *
 * 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_PVR2_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[] = {
	{ CT_VGA, "VGA" }, { CT_RGB, "RGB" }, { CT_COMPOSITE, "COMPOSITE" },
};

static struct pvr2_params outputs[] = {
	{ 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 = {
	.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 = {
	.xres =		640,
	.yres =		480,
	.xres_virtual =	640,
	.yres_virtual = 480,
	.bits_per_pixel	=16,
	.red =		{ 11, 5, 0 },
	.green </