4 * Xilinx TFT LCD frame buffer driver
6 * Author: MontaVista Software, Inc.
9 * 2002-2007 (c) MontaVista Software, Inc.
10 * 2007 (c) Secret Lab Technologies, Ltd.
12 * This file is licensed under the terms of the GNU General Public License
13 * version 2. This program is licensed "as is" without any warranty of any
14 * kind, whether express or implied.
18 * This driver was based on au1100fb.c by MontaVista rewritten for 2.6
19 * by Embedded Alley Solutions <source@embeddedalley.com>, which in turn
20 * was based on skeletonfb.c, Skeleton for a frame buffer device by
24 #include <linux/device.h>
25 #include <linux/module.h>
26 #include <linux/kernel.h>
27 #include <linux/errno.h>
28 #include <linux/string.h>
31 #include <linux/init.h>
32 #include <linux/dma-mapping.h>
33 #include <linux/platform_device.h>
34 #if defined(CONFIG_OF)
35 #include <linux/of_device.h>
36 #include <linux/of_platform.h>
39 #include <linux/xilinxfb.h>
41 #define DRIVER_NAME "xilinxfb"
42 #define DRIVER_DESCRIPTION "Xilinx TFT LCD frame buffer driver"
45 * Xilinx calls it "PLB TFT LCD Controller" though it can also be used for
46 * the VGA port on the Xilinx ML40x board. This is a hardware display controller
47 * for a 640x480 resolution TFT or VGA screen.
49 * The interface to the framebuffer is nice and simple. There are two
50 * control registers. The first tells the LCD interface where in memory
51 * the frame buffer is (only the 11 most significant bits are used, so
52 * don't start thinking about scrolling). The second allows the LCD to
53 * be turned on or off as well as rotated 180 degrees.
58 #define REG_CTRL_ENABLE 0x0001
59 #define REG_CTRL_ROTATE 0x0002
62 * The hardware only handles a single mode: 640x480 24 bit true
63 * color. Each pixel gets a word (32 bits) of memory. Within each word,
64 * the 8 most significant bits are ignored, the next 8 bits are the red
65 * level, the next 8 bits are the green level and the 8 least
66 * significant bits are the blue level. Each row of the LCD uses 1024
67 * words, but only the first 640 pixels are displayed with the other 384
68 * words being ignored. There are 480 rows.
70 #define BYTES_PER_PIXEL 4
71 #define BITS_PER_PIXEL (BYTES_PER_PIXEL * 8)
77 #define PALETTE_ENTRIES_NO 16 /* passed to fb_alloc_cmap() */
80 * Default xilinxfb configuration
82 static struct xilinxfb_platform_data xilinx_fb_default_pdata = {
90 * Here are the default fb_fix_screeninfo and fb_var_screeninfo structures
92 static struct fb_fix_screeninfo xilinx_fb_fix = {
94 .type = FB_TYPE_PACKED_PIXELS,
95 .visual = FB_VISUAL_TRUECOLOR,
96 .accel = FB_ACCEL_NONE
99 static struct fb_var_screeninfo xilinx_fb_var = {
100 .bits_per_pixel = BITS_PER_PIXEL,
102 .red = { RED_SHIFT, 8, 0 },
103 .green = { GREEN_SHIFT, 8, 0 },
104 .blue = { BLUE_SHIFT, 8, 0 },
105 .transp = { 0, 0, 0 },
107 .activate = FB_ACTIVATE_NOW
110 struct xilinxfb_drvdata {
112 struct fb_info info; /* FB driver info record */
114 u32 regs_phys; /* phys. address of the control registers */
115 u32 __iomem *regs; /* virt. address of the control registers */
117 void *fb_virt; /* virt. address of the frame buffer */
118 dma_addr_t fb_phys; /* phys. address of the frame buffer */
119 int fb_alloced; /* Flag, was the fb memory alloced? */
121 u32 reg_ctrl_default;
123 u32 pseudo_palette[PALETTE_ENTRIES_NO];
124 /* Fake palette of 16 colors */
127 #define to_xilinxfb_drvdata(_info) \
128 container_of(_info, struct xilinxfb_drvdata, info)
131 * The LCD controller has DCR interface to its registers, but all
132 * the boards and configurations the driver has been tested with
133 * use opb2dcr bridge. So the registers are seen as memory mapped.
134 * This macro is to make it simple to add the direct DCR access
137 #define xilinx_fb_out_be32(driverdata, offset, val) \
138 out_be32(driverdata->regs + offset, val)
141 xilinx_fb_setcolreg(unsigned regno, unsigned red, unsigned green, unsigned blue,
142 unsigned transp, struct fb_info *fbi)
144 u32 *palette = fbi->pseudo_palette;
146 if (regno >= PALETTE_ENTRIES_NO)
149 if (fbi->var.grayscale) {
150 /* Convert color to grayscale.
151 * grayscale = 0.30*R + 0.59*G + 0.11*B */
153 (red * 77 + green * 151 + blue * 28 + 127) >> 8;
156 /* fbi->fix.visual is always FB_VISUAL_TRUECOLOR */
158 /* We only handle 8 bits of each color. */
162 palette[regno] = (red << RED_SHIFT) | (green << GREEN_SHIFT) |
163 (blue << BLUE_SHIFT);
169 xilinx_fb_blank(int blank_mode, struct fb_info *fbi)
171 struct xilinxfb_drvdata *drvdata = to_xilinxfb_drvdata(fbi);
173 switch (blank_mode) {
174 case FB_BLANK_UNBLANK:
176 xilinx_fb_out_be32(drvdata, REG_CTRL, drvdata->reg_ctrl_default);
179 case FB_BLANK_NORMAL:
180 case FB_BLANK_VSYNC_SUSPEND:
181 case FB_BLANK_HSYNC_SUSPEND:
182 case FB_BLANK_POWERDOWN:
184 xilinx_fb_out_be32(drvdata, REG_CTRL, 0);
189 return 0; /* success */
192 static struct fb_ops xilinxfb_ops =
194 .owner = THIS_MODULE,
195 .fb_setcolreg = xilinx_fb_setcolreg,
196 .fb_blank = xilinx_fb_blank,
197 .fb_fillrect = cfb_fillrect,
198 .fb_copyarea = cfb_copyarea,
199 .fb_imageblit = cfb_imageblit,
202 /* ---------------------------------------------------------------------
203 * Bus independent setup/teardown
206 static int xilinxfb_assign(struct device *dev, unsigned long physaddr,
207 struct xilinxfb_platform_data *pdata)
209 struct xilinxfb_drvdata *drvdata;
211 int fbsize = pdata->xvirt * pdata->yvirt * BYTES_PER_PIXEL;
213 /* Allocate the driver data region */
214 drvdata = kzalloc(sizeof(*drvdata), GFP_KERNEL);
216 dev_err(dev, "Couldn't allocate device private record\n");
219 dev_set_drvdata(dev, drvdata);
221 /* Map the control registers in */
222 if (!request_mem_region(physaddr, 8, DRIVER_NAME)) {
223 dev_err(dev, "Couldn't lock memory region at 0x%08lX\n",
228 drvdata->regs_phys = physaddr;
229 drvdata->regs = ioremap(physaddr, 8);
230 if (!drvdata->regs) {
231 dev_err(dev, "Couldn't lock memory region at 0x%08lX\n",
237 /* Allocate the framebuffer memory */
238 if (pdata->fb_phys) {
239 drvdata->fb_phys = pdata->fb_phys;
240 drvdata->fb_virt = ioremap(pdata->fb_phys, fbsize);
242 drvdata->fb_alloced = 1;
243 drvdata->fb_virt = dma_alloc_coherent(dev, PAGE_ALIGN(fbsize),
244 &drvdata->fb_phys, GFP_KERNEL);
247 if (!drvdata->fb_virt) {
248 dev_err(dev, "Could not allocate frame buffer memory\n");
253 /* Clear (turn to black) the framebuffer */
254 memset_io((void __iomem *)drvdata->fb_virt, 0, fbsize);
256 /* Tell the hardware where the frame buffer is */
257 xilinx_fb_out_be32(drvdata, REG_FB_ADDR, drvdata->fb_phys);
259 /* Turn on the display */
260 drvdata->reg_ctrl_default = REG_CTRL_ENABLE;
261 if (pdata->rotate_screen)
262 drvdata->reg_ctrl_default |= REG_CTRL_ROTATE;
263 xilinx_fb_out_be32(drvdata, REG_CTRL, drvdata->reg_ctrl_default);
265 /* Fill struct fb_info */
266 drvdata->info.device = dev;
267 drvdata->info.screen_base = (void __iomem *)drvdata->fb_virt;
268 drvdata->info.fbops = &xilinxfb_ops;
269 drvdata->info.fix = xilinx_fb_fix;
270 drvdata->info.fix.smem_start = drvdata->fb_phys;
271 drvdata->info.fix.smem_len = fbsize;
272 drvdata->info.fix.line_length = pdata->xvirt * BYTES_PER_PIXEL;
274 drvdata->info.pseudo_palette = drvdata->pseudo_palette;
275 drvdata->info.flags = FBINFO_DEFAULT;
276 drvdata->info.var = xilinx_fb_var;
277 drvdata->info.var.height = pdata->screen_height_mm;
278 drvdata->info.var.width = pdata->screen_width_mm;
279 drvdata->info.var.xres = pdata->xres;
280 drvdata->info.var.yres = pdata->yres;
281 drvdata->info.var.xres_virtual = pdata->xvirt;
282 drvdata->info.var.yres_virtual = pdata->yvirt;
284 /* Allocate a colour map */
285 rc = fb_alloc_cmap(&drvdata->info.cmap, PALETTE_ENTRIES_NO, 0);
287 dev_err(dev, "Fail to allocate colormap (%d entries)\n",
292 /* Register new frame buffer */
293 rc = register_framebuffer(&drvdata->info);
295 dev_err(dev, "Could not register frame buffer\n");
299 /* Put a banner in the log (for DEBUG) */
300 dev_dbg(dev, "regs: phys=%lx, virt=%p\n", physaddr, drvdata->regs);
301 dev_dbg(dev, "fb: phys=%llx, virt=%p, size=%x\n",
302 (unsigned long long) drvdata->fb_phys, drvdata->fb_virt,
305 return 0; /* success */
308 fb_dealloc_cmap(&drvdata->info.cmap);
311 if (drvdata->fb_alloced)
312 dma_free_coherent(dev, PAGE_ALIGN(fbsize), drvdata->fb_virt,
314 /* Turn off the display */
315 xilinx_fb_out_be32(drvdata, REG_CTRL, 0);
318 iounmap(drvdata->regs);
321 release_mem_region(physaddr, 8);
325 dev_set_drvdata(dev, NULL);
330 static int xilinxfb_release(struct device *dev)
332 struct xilinxfb_drvdata *drvdata = dev_get_drvdata(dev);
334 #if !defined(CONFIG_FRAMEBUFFER_CONSOLE) && defined(CONFIG_LOGO)
335 xilinx_fb_blank(VESA_POWERDOWN, &drvdata->info);
338 unregister_framebuffer(&drvdata->info);
340 fb_dealloc_cmap(&drvdata->info.cmap);
342 if (drvdata->fb_alloced)
343 dma_free_coherent(dev, PAGE_ALIGN(drvdata->info.fix.smem_len),
344 drvdata->fb_virt, drvdata->fb_phys);
346 /* Turn off the display */
347 xilinx_fb_out_be32(drvdata, REG_CTRL, 0);
348 iounmap(drvdata->regs);
350 release_mem_region(drvdata->regs_phys, 8);
353 dev_set_drvdata(dev, NULL);
358 /* ---------------------------------------------------------------------
359 * Platform bus binding
363 xilinxfb_platform_probe(struct platform_device *pdev)
365 struct xilinxfb_platform_data *pdata;
366 struct resource *res;
368 /* Find the registers address */
369 res = platform_get_resource(pdev, IORESOURCE_IO, 0);
371 dev_err(&pdev->dev, "Couldn't get registers resource\n");
375 /* If a pdata structure is provided, then extract the parameters */
376 pdata = &xilinx_fb_default_pdata;
377 if (pdev->dev.platform_data) {
378 pdata = pdev->dev.platform_data;
380 pdata->xres = xilinx_fb_default_pdata.xres;
382 pdata->yres = xilinx_fb_default_pdata.yres;
384 pdata->xvirt = xilinx_fb_default_pdata.xvirt;
386 pdata->yvirt = xilinx_fb_default_pdata.yvirt;
389 return xilinxfb_assign(&pdev->dev, res->start, pdata);
393 xilinxfb_platform_remove(struct platform_device *pdev)
395 return xilinxfb_release(&pdev->dev);
399 static struct platform_driver xilinxfb_platform_driver = {
400 .probe = xilinxfb_platform_probe,
401 .remove = xilinxfb_platform_remove,
403 .owner = THIS_MODULE,
408 /* ---------------------------------------------------------------------
412 #if defined(CONFIG_OF)
414 xilinxfb_of_probe(struct of_device *op, const struct of_device_id *match)
418 struct xilinxfb_platform_data pdata;
421 /* Copy with the default pdata (not a ptr reference!) */
422 pdata = xilinx_fb_default_pdata;
424 dev_dbg(&op->dev, "xilinxfb_of_probe(%p, %p)\n", op, match);
426 rc = of_address_to_resource(op->node, 0, &res);
428 dev_err(&op->dev, "invalid address\n");
432 prop = of_get_property(op->node, "phys-size", &size);
433 if ((prop) && (size >= sizeof(u32)*2)) {
434 pdata.screen_width_mm = prop[0];
435 pdata.screen_height_mm = prop[1];
438 prop = of_get_property(op->node, "resolution", &size);
439 if ((prop) && (size >= sizeof(u32)*2)) {
440 pdata.xres = prop[0];
441 pdata.yres = prop[1];
444 prop = of_get_property(op->node, "virtual-resolution", &size);
445 if ((prop) && (size >= sizeof(u32)*2)) {
446 pdata.xvirt = prop[0];
447 pdata.yvirt = prop[1];
450 if (of_find_property(op->node, "rotate-display", NULL))
451 pdata.rotate_screen = 1;
453 return xilinxfb_assign(&op->dev, res.start, &pdata);
456 static int __devexit xilinxfb_of_remove(struct of_device *op)
458 return xilinxfb_release(&op->dev);
461 /* Match table for of_platform binding */
462 static struct of_device_id xilinxfb_of_match[] __devinitdata = {
463 { .compatible = "xlnx,plb-tft-cntlr-ref-1.00.a", },
466 MODULE_DEVICE_TABLE(of, xilinxfb_of_match);
468 static struct of_platform_driver xilinxfb_of_driver = {
469 .owner = THIS_MODULE,
471 .match_table = xilinxfb_of_match,
472 .probe = xilinxfb_of_probe,
473 .remove = __devexit_p(xilinxfb_of_remove),
479 /* Registration helpers to keep the number of #ifdefs to a minimum */
480 static inline int __init xilinxfb_of_register(void)
482 pr_debug("xilinxfb: calling of_register_platform_driver()\n");
483 return of_register_platform_driver(&xilinxfb_of_driver);
486 static inline void __exit xilinxfb_of_unregister(void)
488 of_unregister_platform_driver(&xilinxfb_of_driver);
490 #else /* CONFIG_OF */
491 /* CONFIG_OF not enabled; do nothing helpers */
492 static inline int __init xilinxfb_of_register(void) { return 0; }
493 static inline void __exit xilinxfb_of_unregister(void) { }
494 #endif /* CONFIG_OF */
496 /* ---------------------------------------------------------------------
497 * Module setup and teardown
504 rc = xilinxfb_of_register();
508 rc = platform_driver_register(&xilinxfb_platform_driver);
510 xilinxfb_of_unregister();
516 xilinxfb_cleanup(void)
518 platform_driver_unregister(&xilinxfb_platform_driver);
519 xilinxfb_of_unregister();
522 module_init(xilinxfb_init);
523 module_exit(xilinxfb_cleanup);
525 MODULE_AUTHOR("MontaVista Software, Inc. <source@mvista.com>");
526 MODULE_DESCRIPTION(DRIVER_DESCRIPTION);
527 MODULE_LICENSE("GPL");