video: Add Aeroflex Gaisler GRVGA framebuffer device driver

This patch adds support for the GRVGA framebuffer IP core from Aeroflex Gaisler.
The device is used in LEON SPARCV8 based System on Chips. Documentation can
be found here: www.gaisler.com/products/grlib/grip.pdf.

Signed-off-by: Kristoffer Glembo <kristoffer@gaisler.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 579 insertions, 0 deletions

diff --git a/drivers/video/grvga.c b/drivers/video/grvga.c
new file mode 100644
index 0000000..f37e025
--- /dev/null
+++ b/drivers/video/grvga.c
@@ -0,0 +1,579 @@
+/*
+ * Driver for Aeroflex Gaisler SVGACTRL framebuffer device.
+ *
+ * 2011 (c) Aeroflex Gaisler AB
+ *
+ * Full documentation of the core can be found here:
+ * http://www.gaisler.com/products/grlib/grip.pdf
+ *
+ * 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.
+ *
+ * Contributors: Kristoffer Glembo <kristoffer@gaisler.com>
+ *
+ */
+
+#include <linux/platform_device.h>
+#include <linux/dma-mapping.h>
+#include <linux/of_platform.h>
+#include <linux/of_device.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/tty.h>
+#include <linux/mm.h>
+#include <linux/fb.h>
+#include <linux/io.h>
+
+struct grvga_regs {
+	u32 status; 		/* 0x00 */
+	u32 video_length; 	/* 0x04 */
+	u32 front_porch;	/* 0x08 */
+	u32 sync_length;	/* 0x0C */
+	u32 line_length;	/* 0x10 */
+	u32 fb_pos;		/* 0x14 */
+	u32 clk_vector[4];	/* 0x18 */
+	u32 clut;	        /* 0x20 */
+};
+
+struct grvga_par {
+	struct grvga_regs *regs;
+	u32 color_palette[16];  /* 16 entry pseudo palette used by fbcon in true color mode */
+	int clk_sel;
+	int fb_alloced;         /* = 1 if framebuffer is allocated in main memory */
+};
+
+
+static const struct fb_videomode grvga_modedb[] = {
+    {
+	/* 640x480 @ 60 Hz */
+	NULL, 60, 640, 480, 40000, 48, 16, 39, 11, 96, 2,
+	0, FB_VMODE_NONINTERLACED
+    }, {
+	/* 800x600 @ 60 Hz */
+	NULL, 60, 800, 600, 25000, 88, 40, 23, 1, 128, 4,
+	0, FB_VMODE_NONINTERLACED
+    }, {
+	/* 800x600 @ 72 Hz */
+	NULL, 72, 800, 600, 20000, 64, 56, 23, 37, 120, 6,
+	0, FB_VMODE_NONINTERLACED
+    }, {
+	/* 1024x768 @ 60 Hz */
+	NULL, 60, 1024, 768, 15385, 160, 24, 29, 3, 136, 6,
+	0, FB_VMODE_NONINTERLACED
+    }
+ };
+
+static struct fb_fix_screeninfo grvga_fix __initdata = {
+	.id =		"AG SVGACTRL",
+	.type =		FB_TYPE_PACKED_PIXELS,
+	.visual =       FB_VISUAL_PSEUDOCOLOR,
+	.xpanstep =	0,
+	.ypanstep =	1,
+	.ywrapstep =	0,
+	.accel =	FB_ACCEL_NONE,
+};
+
+static int grvga_check_var(struct fb_var_screeninfo *var,
+			   struct fb_info *info)
+{
+	struct grvga_par *par = info->par;
+	int i;
+
+	if (!var->xres)
+		var->xres = 1;
+	if (!var->yres)
+		var->yres = 1;
+	if (var->bits_per_pixel <= 8)
+		var->bits_per_pixel = 8;
+	else if (var->bits_per_pixel <= 16)
+		var->bits_per_pixel = 16;
+	else if (var->bits_per_pixel <= 24)
+		var->bits_per_pixel = 24;
+	else if (var->bits_per_pixel <= 32)
+		var->bits_per_pixel = 32;
+	else
+		return -EINVAL;
+
+	var->xres_virtual = var->xres;
+	var->yres_virtual = 2*var->yres;
+
+	if (info->fix.smem_len) {
+		if ((var->yres_virtual*var->xres_virtual*var->bits_per_pixel/8) > info->fix.smem_len)
+			return -ENOMEM;
+	}
+
+	/* Which clocks that are available can be read out in these registers */
+	for (i = 0; i <= 3 ; i++) {
+		if (var->pixclock == par->regs->clk_vector[i])
+			break;
+	}
+	if (i <= 3)
+		par->clk_sel = i;
+	else
+		return -EINVAL;
+
+	switch (info->var.bits_per_pixel) {
+	case 8:
+		var->red   = (struct fb_bitfield) {0, 8, 0};      /* offset, length, msb-right */
+		var->green = (struct fb_bitfield) {0, 8, 0};
+		var->blue  = (struct fb_bitfield) {0, 8, 0};
+		var->transp = (struct fb_bitfield) {0, 0, 0};
+		break;
+	case 16:
+		var->red   = (struct fb_bitfield) {11, 5, 0};
+		var->green = (struct fb_bitfield) {5, 6, 0};
+		var->blue  = (struct fb_bitfield) {0, 5, 0};
+		var->transp = (struct fb_bitfield) {0, 0, 0};
+		break;
+	case 24:
+	case 32:
+		var->red   = (struct fb_bitfield) {16, 8, 0};
+		var->green = (struct fb_bitfield) {8, 8, 0};
+		var->blue  = (struct fb_bitfield) {0, 8, 0};
+		var->transp = (struct fb_bitfield) {24, 8, 0};
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int grvga_set_par(struct fb_info *info)
+{
+
+	u32 func = 0;
+	struct grvga_par *par = info->par;
+
+	__raw_writel(((info->var.yres - 1) << 16) | (info->var.xres - 1),
+		     &par->regs->video_length);
+
+	__raw_writel((info->var.lower_margin << 16) | (info->var.right_margin),
+		     &par->regs->front_porch);
+
+	__raw_writel((info->var.vsync_len << 16) | (info->var.hsync_len),
+		     &par->regs->sync_length);
+
+	__raw_writel(((info->var.yres + info->var.lower_margin + info->var.upper_margin + info->var.vsync_len - 1) << 16) |
+		     (info->var.xres + info->var.right_margin + info->var.left_margin + info->var.hsync_len - 1),
+		     &par->regs->line_length);
+
+	switch (info->var.bits_per_pixel) {
+	case 8:
+		info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
+		func = 1;
+		break;
+	case 16:
+		info->fix.visual = FB_VISUAL_TRUECOLOR;
+		func = 2;
+		break;
+	case 24:
+	case 32:
+		info->fix.visual = FB_VISUAL_TRUECOLOR;
+		func = 3;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	__raw_writel((par->clk_sel << 6) | (func << 4) | 1,
+		     &par->regs->status);
+
+	info->fix.line_length = (info->var.xres_virtual*info->var.bits_per_pixel)/8;
+	return 0;
+}
+
+static int grvga_setcolreg(unsigned regno, unsigned red, unsigned green, unsigned blue, unsigned transp, struct fb_info *info)
+{
+	struct grvga_par *par;
+	par = info->par;
+
+	if (regno >= 256)	/* Size of CLUT */
+		return -EINVAL;
+
+	if (info->var.grayscale) {
+		/* grayscale = 0.30*R + 0.59*G + 0.11*B */
+		red = green = blue = (red * 77 + green * 151 + blue * 28) >> 8;
+	}
+
+
+
+#define CNVT_TOHW(val, width) ((((val)<<(width))+0x7FFF-(val))>>16)
+
+	red    = CNVT_TOHW(red,   info->var.red.length);
+	green  = CNVT_TOHW(green, info->var.green.length);
+	blue   = CNVT_TOHW(blue,  info->var.blue.length);
+	transp = CNVT_TOHW(transp, info->var.transp.length);
+
+#undef CNVT_TOHW
+
+	/* In PSEUDOCOLOR we use the hardware CLUT */
+	if (info->fix.visual == FB_VISUAL_PSEUDOCOLOR)
+		__raw_writel((regno << 24) | (red << 16) | (green << 8) | blue,
+			     &par->regs->clut);
+
+	/* Truecolor uses the pseudo palette */
+	else if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
+		u32 v;
+		if (regno >= 16)
+			return -EINVAL;
+
+
+		v =     (red    << info->var.red.offset)   |
+			(green  << info->var.green.offset) |
+			(blue   << info->var.blue.offset)  |
+			(transp << info->var.transp.offset);
+
+		((u32 *) (info->pseudo_palette))[regno] = v;
+	}
+	return 0;
+}
+
+static int grvga_pan_display(struct fb_var_screeninfo *var,
+			     struct fb_info *info)
+{
+	struct grvga_par *par = info->par;
+	struct fb_fix_screeninfo *fix = &info->fix;
+	u32 base_addr;
+
+	if (var->xoffset != 0)
+		return -EINVAL;
+
+	base_addr = fix->smem_start + (var->yoffset * fix->line_length);
+	base_addr &= ~3UL;
+
+	/* Set framebuffer base address  */
+	__raw_writel(base_addr,
+		     &par->regs->fb_pos);
+
+	return 0;
+}
+
+static struct fb_ops grvga_ops = {
+	.owner          = THIS_MODULE,
+	.fb_check_var   = grvga_check_var,
+	.fb_set_par	= grvga_set_par,
+	.fb_setcolreg   = grvga_setcolreg,
+	.fb_pan_display = grvga_pan_display,
+	.fb_fillrect	= cfb_fillrect,
+	.fb_copyarea	= cfb_copyarea,
+	.fb_imageblit	= cfb_imageblit
+};
+
+static int __init grvga_parse_custom(char *options,
+				     struct fb_var_screeninfo *screendata)
+{
+	char *this_opt;
+	int count = 0;
+	if (!options || !*options)
+		return -1;
+
+	while ((this_opt = strsep(&options, " ")) != NULL) {
+		if (!*this_opt)
+			continue;
+
+		switch (count) {
+		case 0:
+			screendata->pixclock = simple_strtoul(this_opt, NULL, 0);
+			count++;
+			break;
+		case 1:
+			screendata->xres = screendata->xres_virtual = simple_strtoul(this_opt, NULL, 0);
+			count++;
+			break;
+		case 2:
+			screendata->right_margin = simple_strtoul(this_opt, NULL, 0);
+			count++;
+			break;
+		case 3:
+			screendata->hsync_len = simple_strtoul(this_opt, NULL, 0);
+			count++;
+			break;
+		case 4:
+			screendata->left_margin = simple_strtoul(this_opt, NULL, 0);
+			count++;
+			break;
+		case 5:
+			screendata->yres = screendata->yres_virtual = simple_strtoul(this_opt, NULL, 0);
+			count++;
+			break;
+		case 6:
+			screendata->lower_margin = simple_strtoul(this_opt, NULL, 0);
+			count++;
+			break;
+		case 7:
+			screendata->vsync_len = simple_strtoul(this_opt, NULL, 0);
+			count++;
+			break;
+		case 8:
+			screendata->upper_margin = simple_strtoul(this_opt, NULL, 0);
+			count++;
+			break;
+		case 9:
+			screendata->bits_per_pixel = simple_strtoul(this_opt, NULL, 0);
+			count++;
+			break;
+		default:
+			return -1;
+		}
+	}
+	screendata->activate  = FB_ACTIVATE_NOW;
+	screendata->vmode     = FB_VMODE_NONINTERLACED;
+	return 0;
+}
+
+static int __devinit grvga_probe(struct platform_device *dev)
+{
+	struct fb_info *info;
+	int retval = -ENOMEM;
+	unsigned long virtual_start;
+	unsigned long grvga_fix_addr = 0;
+	unsigned long physical_start = 0;
+	unsigned long grvga_mem_size = 0;
+	struct grvga_par *par = NULL;
+	char *options = NULL, *mode_opt = NULL;
+
+	info = framebuffer_alloc(sizeof(struct grvga_par), &dev->dev);
+	if (!info) {
+		dev_err(&dev->dev, "framebuffer_alloc failed\n");
+		return -ENOMEM;
+	}
+
+	/* Expecting: "grvga: modestring, [addr:<framebuffer physical address>], [size:<framebuffer size>]
+	 *
+	 * If modestring is custom:<custom mode string> we parse the string which then contains all videoparameters
+	 * If address is left out, we allocate memory,
+	 * if size is left out we only allocate enough to support the given mode.
+	 */
+	if (fb_get_options("grvga", &options)) {
+		retval = -ENODEV;
+		goto err;
+	}
+
+	if (!options || !*options)
+		options =  "640x480-8@60";
+
+	while (1) {
+		char *this_opt = strsep(&options, ",");
+
+		if (!this_opt)
+			break;
+
+		if (!strncmp(this_opt, "custom", 6)) {
+			if (grvga_parse_custom(this_opt, &info->var) < 0) {
+				dev_err(&dev->dev, "Failed to parse custom mode (%s).\n", this_opt);
+				retval = -EINVAL;
+				goto err1;
+			}
+		} else if (!strncmp(this_opt, "addr", 4))
+			grvga_fix_addr = simple_strtoul(this_opt + 5, NULL, 16);
+		else if (!strncmp(this_opt, "size", 4))
+			grvga_mem_size = simple_strtoul(this_opt + 5, NULL, 0);
+		else
+			mode_opt = this_opt;
+	}
+
+	par = info->par;
+	info->fbops = &grvga_ops;
+	info->fix = grvga_fix;
+	info->pseudo_palette = par->color_palette;
+	info->flags = FBINFO_DEFAULT | FBINFO_PARTIAL_PAN_OK | FBINFO_HWACCEL_YPAN;
+	info->fix.smem_len = grvga_mem_size;
+
+	if (!request_mem_region(dev->resource[0].start, resource_size(&dev->resource[0]), "grlib-svgactrl regs")) {
+		dev_err(&dev->dev, "registers already mapped\n");
+		retval = -EBUSY;
+		goto err;
+	}
+
+	par->regs = of_ioremap(&dev->resource[0], 0,
+			       resource_size(&dev->resource[0]),
+			       "grlib-svgactrl regs");
+
+	if (!par->regs) {
+		dev_err(&dev->dev, "failed to map registers\n");
+		retval = -ENOMEM;
+		goto err1;
+	}
+
+	retval = fb_alloc_cmap(&info->cmap, 256, 0);
+	if (retval < 0) {
+		dev_err(&dev->dev, "failed to allocate mem with fb_alloc_cmap\n");
+		retval = -ENOMEM;
+		goto err2;
+	}
+
+	if (mode_opt) {
+		retval = fb_find_mode(&info->var, info, mode_opt,
+				      grvga_modedb, sizeof(grvga_modedb), &grvga_modedb[0], 8);
+		if (!retval || retval == 4) {
+			retval = -EINVAL;
+			goto err3;
+		}
+	}
+
+	if (!grvga_mem_size)
+		grvga_mem_size = info->var.xres_virtual * info->var.yres_virtual * info->var.bits_per_pixel/8;
+
+	if (grvga_fix_addr) {
+		/* Got framebuffer base address from argument list */
+
+		physical_start = grvga_fix_addr;
+
+		if (!request_mem_region(physical_start, grvga_mem_size, dev->name)) {
+			dev_err(&dev->dev, "failed to request memory region\n");
+			retval = -ENOMEM;
+			goto err3;
+		}
+
+		virtual_start = (unsigned long) ioremap(physical_start, grvga_mem_size);
+
+		if (!virtual_start) {
+			dev_err(&dev->dev, "error mapping framebuffer memory\n");
+			retval = -ENOMEM;
+			goto err4;
+		}
+	} else {	/* Allocate frambuffer memory */
+
+		unsigned long page;
+
+		virtual_start = (unsigned long) __get_free_pages(GFP_DMA,
+								 get_order(grvga_mem_size));
+		if (!virtual_start) {
+			dev_err(&dev->dev,
+				"unable to allocate framebuffer memory (%lu bytes)\n",
+				grvga_mem_size);
+			retval = -ENOMEM;
+			goto err3;
+		}
+
+		physical_start = dma_map_single(&dev->dev, (void *)virtual_start, grvga_mem_size, DMA_TO_DEVICE);
+
+		/* Set page reserved so that mmap will work. This is necessary
+		 * since we'll be remapping normal memory.
+		 */
+		for (page = virtual_start;
+		     page < PAGE_ALIGN(virtual_start + grvga_mem_size);
+		     page += PAGE_SIZE) {
+			SetPageReserved(virt_to_page(page));
+		}
+
+		par->fb_alloced = 1;
+	}
+
+	memset((unsigned long *) virtual_start, 0, grvga_mem_size);
+
+	info->screen_base = (char __iomem *) virtual_start;
+	info->fix.smem_start = physical_start;
+	info->fix.smem_len   = grvga_mem_size;
+
+	dev_set_drvdata(&dev->dev, info);
+
+	dev_info(&dev->dev,
+		 "Aeroflex Gaisler framebuffer device (fb%d), %dx%d-%d, using %luK of video memory @ %p\n",
+		 info->node, info->var.xres, info->var.yres, info->var.bits_per_pixel,
+		 grvga_mem_size >> 10, info->screen_base);
+
+	retval = register_framebuffer(info);
+	if (retval < 0) {
+		dev_err(&dev->dev, "failed to register framebuffer\n");
+		goto err4;
+	}
+
+	__raw_writel(physical_start, &par->regs->fb_pos);
+	__raw_writel(__raw_readl(&par->regs->status) | 1,  /* Enable framebuffer */
+		     &par->regs->status);
+
+	return 0;
+
+err4:
+	dev_set_drvdata(&dev->dev, NULL);
+	if (grvga_fix_addr) {
+		release_mem_region(physical_start, grvga_mem_size);
+		iounmap((void *)virtual_start);
+	} else
+		kfree((void *)virtual_start);
+err3:
+	fb_dealloc_cmap(&info->cmap);
+err2:
+	of_iounmap(&dev->resource[0], par->regs,
+		   resource_size(&dev->resource[0]));
+err1:
+	release_mem_region(dev->resource[0].start, resource_size(&dev->resource[0]));
+err:
+	framebuffer_release(info);
+
+	return retval;
+}
+
+static int __devexit grvga_remove(struct platform_device *device)
+{
+	struct fb_info *info = dev_get_drvdata(&device->dev);
+	struct grvga_par *par = info->par;
+
+	if (info) {
+		unregister_framebuffer(info);
+		fb_dealloc_cmap(&info->cmap);
+
+		of_iounmap(&device->resource[0], par->regs,
+			   resource_size(&device->resource[0]));
+		release_mem_region(device->resource[0].start, resource_size(&device->resource[0]));
+
+		if (!par->fb_alloced) {
+			release_mem_region(info->fix.smem_start, info->fix.smem_len);
+			iounmap(info->screen_base);
+		} else
+			kfree((void *)info->screen_base);
+
+		framebuffer_release(info);
+		dev_set_drvdata(&device->dev, NULL);
+	}
+
+	return 0;
+}
+
+static struct of_device_id svgactrl_of_match[] = {
+	{
+		.name = "GAISLER_SVGACTRL",
+	},
+	{
+		.name = "01_063",
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, svgactrl_of_match);
+
+static struct platform_driver grvga_driver = {
+	.driver = {
+		.name = "grlib-svgactrl",
+		.owner = THIS_MODULE,
+		.of_match_table = svgactrl_of_match,
+	},
+	.probe		= grvga_probe,
+	.remove		= __devexit_p(grvga_remove),
+};
+
+
+static int __init grvga_init(void)
+{
+	return platform_driver_register(&grvga_driver);
+}
+
+static void __exit grvga_exit(void)
+{
+	platform_driver_unregister(&grvga_driver);
+}
+
+module_init(grvga_init);
+module_exit(grvga_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Aeroflex Gaisler");
+MODULE_DESCRIPTION("Aeroflex Gaisler framebuffer device driver");