1 /*
2 * Xilinx TFT frame buffer driver
3 *
4 * Author: MontaVista Software, Inc.
5 * source@mvista.com
6 *
7 * 2002-2007 (c) MontaVista Software, Inc.
8 * 2007 (c) Secret Lab Technologies, Ltd.
9 * 2009 (c) Xilinx Inc.
10 *
11 * This file is licensed under the terms of the GNU General Public License
12 * version 2. This program is licensed "as is" without any warranty of any
13 * kind, whether express or implied.
14 */
15
16 /*
17 * This driver was based on au1100fb.c by MontaVista rewritten for 2.6
18 * by Embedded Alley Solutions <source@embeddedalley.com>, which in turn
19 * was based on skeletonfb.c, Skeleton for a frame buffer device by
20 * Geert Uytterhoeven.
21 */
22
23 #include <linux/device.h>
24 #include <linux/module.h>
25 #include <linux/kernel.h>
26 #include <linux/errno.h>
27 #include <linux/string.h>
28 #include <linux/mm.h>
29 #include <linux/fb.h>
30 #include <linux/init.h>
31 #include <linux/dma-mapping.h>
32 #include <linux/of_device.h>
33 #include <linux/of_platform.h>
34 #include <linux/of_address.h>
35 #include <linux/io.h>
36 #include <linux/xilinxfb.h>
37 #include <linux/slab.h>
38
39 #ifdef CONFIG_PPC_DCR
40 #include <asm/dcr.h>
41 #endif
42
43 #define DRIVER_NAME "xilinxfb"
44
45
46 /*
47 * Xilinx calls it "PLB TFT LCD Controller" though it can also be used for
48 * the VGA port on the Xilinx ML40x board. This is a hardware display
49 * controller for a 640x480 resolution TFT or VGA screen.
50 *
51 * The interface to the framebuffer is nice and simple. There are two
52 * control registers. The first tells the LCD interface where in memory
53 * the frame buffer is (only the 11 most significant bits are used, so
54 * don't start thinking about scrolling). The second allows the LCD to
55 * be turned on or off as well as rotated 180 degrees.
56 *
57 * In case of direct PLB access the second control register will be at
58 * an offset of 4 as compared to the DCR access where the offset is 1
59 * i.e. REG_CTRL. So this is taken care in the function
60 * xilinx_fb_out_be32 where it left shifts the offset 2 times in case of
61 * direct PLB access.
62 */
63 #define NUM_REGS 2
64 #define REG_FB_ADDR 0
65 #define REG_CTRL 1
66 #define REG_CTRL_ENABLE 0x0001
67 #define REG_CTRL_ROTATE 0x0002
68
69 /*
70 * The hardware only handles a single mode: 640x480 24 bit true
71 * color. Each pixel gets a word (32 bits) of memory. Within each word,
72 * the 8 most significant bits are ignored, the next 8 bits are the red
73 * level, the next 8 bits are the green level and the 8 least
74 * significant bits are the blue level. Each row of the LCD uses 1024
75 * words, but only the first 640 pixels are displayed with the other 384
76 * words being ignored. There are 480 rows.
77 */
78 #define BYTES_PER_PIXEL 4
79 #define BITS_PER_PIXEL (BYTES_PER_PIXEL * 8)
80
81 #define RED_SHIFT 16
82 #define GREEN_SHIFT 8
83 #define BLUE_SHIFT 0
84
85 #define PALETTE_ENTRIES_NO 16 /* passed to fb_alloc_cmap() */
86
87 /*
88 * Default xilinxfb configuration
89 */
90 static struct xilinxfb_platform_data xilinx_fb_default_pdata = {
91 .xres = 640,
92 .yres = 480,
93 .xvirt = 1024,
94 .yvirt = 480,
95 };
96
97 /*
98 * Here are the default fb_fix_screeninfo and fb_var_screeninfo structures
99 */
100 static struct fb_fix_screeninfo xilinx_fb_fix = {
101 .id = "Xilinx",
102 .type = FB_TYPE_PACKED_PIXELS,
103 .visual = FB_VISUAL_TRUECOLOR,
104 .accel = FB_ACCEL_NONE
105 };
106
107 static struct fb_var_screeninfo xilinx_fb_var = {
108 .bits_per_pixel = BITS_PER_PIXEL,
109
110 .red = { RED_SHIFT, 8, 0 },
111 .green = { GREEN_SHIFT, 8, 0 },
112 .blue = { BLUE_SHIFT, 8, 0 },
113 .transp = { 0, 0, 0 },
114
115 .activate = FB_ACTIVATE_NOW
116 };
117
118
119 #define PLB_ACCESS_FLAG 0x1 /* 1 = PLB, 0 = DCR */
120
121 struct xilinxfb_drvdata {
122
123 struct fb_info info; /* FB driver info record */
124
125 phys_addr_t regs_phys; /* phys. address of the control
126 registers */
127 void __iomem *regs; /* virt. address of the control
128 registers */
129 #ifdef CONFIG_PPC_DCR
130 dcr_host_t dcr_host;
131 unsigned int dcr_len;
132 #endif
133 void *fb_virt; /* virt. address of the frame buffer */
134 dma_addr_t fb_phys; /* phys. address of the frame buffer */
135 int fb_alloced; /* Flag, was the fb memory alloced? */
136
137 u8 flags; /* features of the driver */
138
139 u32 reg_ctrl_default;
140
141 u32 pseudo_palette[PALETTE_ENTRIES_NO];
142 /* Fake palette of 16 colors */
143 };
144
145 #define to_xilinxfb_drvdata(_info) \
146 container_of(_info, struct xilinxfb_drvdata, info)
147
148 /*
149 * The XPS TFT Controller can be accessed through PLB or DCR interface.
150 * To perform the read/write on the registers we need to check on
151 * which bus its connected and call the appropriate write API.
152 */
xilinx_fb_out_be32(struct xilinxfb_drvdata * drvdata,u32 offset,u32 val)153 static void xilinx_fb_out_be32(struct xilinxfb_drvdata *drvdata, u32 offset,
154 u32 val)
155 {
156 if (drvdata->flags & PLB_ACCESS_FLAG)
157 out_be32(drvdata->regs + (offset << 2), val);
158 #ifdef CONFIG_PPC_DCR
159 else
160 dcr_write(drvdata->dcr_host, offset, val);
161 #endif
162 }
163
164 static int
xilinx_fb_setcolreg(unsigned regno,unsigned red,unsigned green,unsigned blue,unsigned transp,struct fb_info * fbi)165 xilinx_fb_setcolreg(unsigned regno, unsigned red, unsigned green, unsigned blue,
166 unsigned transp, struct fb_info *fbi)
167 {
168 u32 *palette = fbi->pseudo_palette;
169
170 if (regno >= PALETTE_ENTRIES_NO)
171 return -EINVAL;
172
173 if (fbi->var.grayscale) {
174 /* Convert color to grayscale.
175 * grayscale = 0.30*R + 0.59*G + 0.11*B */
176 red = green = blue =
177 (red * 77 + green * 151 + blue * 28 + 127) >> 8;
178 }
179
180 /* fbi->fix.visual is always FB_VISUAL_TRUECOLOR */
181
182 /* We only handle 8 bits of each color. */
183 red >>= 8;
184 green >>= 8;
185 blue >>= 8;
186 palette[regno] = (red << RED_SHIFT) | (green << GREEN_SHIFT) |
187 (blue << BLUE_SHIFT);
188
189 return 0;
190 }
191
192 static int
xilinx_fb_blank(int blank_mode,struct fb_info * fbi)193 xilinx_fb_blank(int blank_mode, struct fb_info *fbi)
194 {
195 struct xilinxfb_drvdata *drvdata = to_xilinxfb_drvdata(fbi);
196
197 switch (blank_mode) {
198 case FB_BLANK_UNBLANK:
199 /* turn on panel */
200 xilinx_fb_out_be32(drvdata, REG_CTRL, drvdata->reg_ctrl_default);
201 break;
202
203 case FB_BLANK_NORMAL:
204 case FB_BLANK_VSYNC_SUSPEND:
205 case FB_BLANK_HSYNC_SUSPEND:
206 case FB_BLANK_POWERDOWN:
207 /* turn off panel */
208 xilinx_fb_out_be32(drvdata, REG_CTRL, 0);
209 default:
210 break;
211
212 }
213 return 0; /* success */
214 }
215
216 static struct fb_ops xilinxfb_ops =
217 {
218 .owner = THIS_MODULE,
219 .fb_setcolreg = xilinx_fb_setcolreg,
220 .fb_blank = xilinx_fb_blank,
221 .fb_fillrect = cfb_fillrect,
222 .fb_copyarea = cfb_copyarea,
223 .fb_imageblit = cfb_imageblit,
224 };
225
226 /* ---------------------------------------------------------------------
227 * Bus independent setup/teardown
228 */
229
xilinxfb_assign(struct device * dev,struct xilinxfb_drvdata * drvdata,unsigned long physaddr,struct xilinxfb_platform_data * pdata)230 static int xilinxfb_assign(struct device *dev,
231 struct xilinxfb_drvdata *drvdata,
232 unsigned long physaddr,
233 struct xilinxfb_platform_data *pdata)
234 {
235 int rc;
236 int fbsize = pdata->xvirt * pdata->yvirt * BYTES_PER_PIXEL;
237
238 if (drvdata->flags & PLB_ACCESS_FLAG) {
239 /*
240 * Map the control registers in if the controller
241 * is on direct PLB interface.
242 */
243 if (!request_mem_region(physaddr, 8, DRIVER_NAME)) {
244 dev_err(dev, "Couldn't lock memory region at 0x%08lX\n",
245 physaddr);
246 rc = -ENODEV;
247 goto err_region;
248 }
249
250 drvdata->regs_phys = physaddr;
251 drvdata->regs = ioremap(physaddr, 8);
252 if (!drvdata->regs) {
253 dev_err(dev, "Couldn't lock memory region at 0x%08lX\n",
254 physaddr);
255 rc = -ENODEV;
256 goto err_map;
257 }
258 }
259
260 /* Allocate the framebuffer memory */
261 if (pdata->fb_phys) {
262 drvdata->fb_phys = pdata->fb_phys;
263 drvdata->fb_virt = ioremap(pdata->fb_phys, fbsize);
264 } else {
265 drvdata->fb_alloced = 1;
266 drvdata->fb_virt = dma_alloc_coherent(dev, PAGE_ALIGN(fbsize),
267 &drvdata->fb_phys, GFP_KERNEL);
268 }
269
270 if (!drvdata->fb_virt) {
271 dev_err(dev, "Could not allocate frame buffer memory\n");
272 rc = -ENOMEM;
273 if (drvdata->flags & PLB_ACCESS_FLAG)
274 goto err_fbmem;
275 else
276 goto err_region;
277 }
278
279 /* Clear (turn to black) the framebuffer */
280 memset_io((void __iomem *)drvdata->fb_virt, 0, fbsize);
281
282 /* Tell the hardware where the frame buffer is */
283 xilinx_fb_out_be32(drvdata, REG_FB_ADDR, drvdata->fb_phys);
284
285 /* Turn on the display */
286 drvdata->reg_ctrl_default = REG_CTRL_ENABLE;
287 if (pdata->rotate_screen)
288 drvdata->reg_ctrl_default |= REG_CTRL_ROTATE;
289 xilinx_fb_out_be32(drvdata, REG_CTRL,
290 drvdata->reg_ctrl_default);
291
292 /* Fill struct fb_info */
293 drvdata->info.device = dev;
294 drvdata->info.screen_base = (void __iomem *)drvdata->fb_virt;
295 drvdata->info.fbops = &xilinxfb_ops;
296 drvdata->info.fix = xilinx_fb_fix;
297 drvdata->info.fix.smem_start = drvdata->fb_phys;
298 drvdata->info.fix.smem_len = fbsize;
299 drvdata->info.fix.line_length = pdata->xvirt * BYTES_PER_PIXEL;
300
301 drvdata->info.pseudo_palette = drvdata->pseudo_palette;
302 drvdata->info.flags = FBINFO_DEFAULT;
303 drvdata->info.var = xilinx_fb_var;
304 drvdata->info.var.height = pdata->screen_height_mm;
305 drvdata->info.var.width = pdata->screen_width_mm;
306 drvdata->info.var.xres = pdata->xres;
307 drvdata->info.var.yres = pdata->yres;
308 drvdata->info.var.xres_virtual = pdata->xvirt;
309 drvdata->info.var.yres_virtual = pdata->yvirt;
310
311 /* Allocate a colour map */
312 rc = fb_alloc_cmap(&drvdata->info.cmap, PALETTE_ENTRIES_NO, 0);
313 if (rc) {
314 dev_err(dev, "Fail to allocate colormap (%d entries)\n",
315 PALETTE_ENTRIES_NO);
316 goto err_cmap;
317 }
318
319 /* Register new frame buffer */
320 rc = register_framebuffer(&drvdata->info);
321 if (rc) {
322 dev_err(dev, "Could not register frame buffer\n");
323 goto err_regfb;
324 }
325
326 if (drvdata->flags & PLB_ACCESS_FLAG) {
327 /* Put a banner in the log (for DEBUG) */
328 dev_dbg(dev, "regs: phys=%lx, virt=%p\n", physaddr,
329 drvdata->regs);
330 }
331 /* Put a banner in the log (for DEBUG) */
332 dev_dbg(dev, "fb: phys=%llx, virt=%p, size=%x\n",
333 (unsigned long long)drvdata->fb_phys, drvdata->fb_virt, fbsize);
334
335 return 0; /* success */
336
337 err_regfb:
338 fb_dealloc_cmap(&drvdata->info.cmap);
339
340 err_cmap:
341 if (drvdata->fb_alloced)
342 dma_free_coherent(dev, PAGE_ALIGN(fbsize), drvdata->fb_virt,
343 drvdata->fb_phys);
344 else
345 iounmap(drvdata->fb_virt);
346
347 /* Turn off the display */
348 xilinx_fb_out_be32(drvdata, REG_CTRL, 0);
349
350 err_fbmem:
351 if (drvdata->flags & PLB_ACCESS_FLAG)
352 iounmap(drvdata->regs);
353
354 err_map:
355 if (drvdata->flags & PLB_ACCESS_FLAG)
356 release_mem_region(physaddr, 8);
357
358 err_region:
359 kfree(drvdata);
360 dev_set_drvdata(dev, NULL);
361
362 return rc;
363 }
364
xilinxfb_release(struct device * dev)365 static int xilinxfb_release(struct device *dev)
366 {
367 struct xilinxfb_drvdata *drvdata = dev_get_drvdata(dev);
368
369 #if !defined(CONFIG_FRAMEBUFFER_CONSOLE) && defined(CONFIG_LOGO)
370 xilinx_fb_blank(VESA_POWERDOWN, &drvdata->info);
371 #endif
372
373 unregister_framebuffer(&drvdata->info);
374
375 fb_dealloc_cmap(&drvdata->info.cmap);
376
377 if (drvdata->fb_alloced)
378 dma_free_coherent(dev, PAGE_ALIGN(drvdata->info.fix.smem_len),
379 drvdata->fb_virt, drvdata->fb_phys);
380 else
381 iounmap(drvdata->fb_virt);
382
383 /* Turn off the display */
384 xilinx_fb_out_be32(drvdata, REG_CTRL, 0);
385
386 /* Release the resources, as allocated based on interface */
387 if (drvdata->flags & PLB_ACCESS_FLAG) {
388 iounmap(drvdata->regs);
389 release_mem_region(drvdata->regs_phys, 8);
390 }
391 #ifdef CONFIG_PPC_DCR
392 else
393 dcr_unmap(drvdata->dcr_host, drvdata->dcr_len);
394 #endif
395
396 kfree(drvdata);
397 dev_set_drvdata(dev, NULL);
398
399 return 0;
400 }
401
402 /* ---------------------------------------------------------------------
403 * OF bus binding
404 */
405
xilinxfb_of_probe(struct platform_device * op)406 static int __devinit xilinxfb_of_probe(struct platform_device *op)
407 {
408 const u32 *prop;
409 u32 *p;
410 u32 tft_access;
411 struct xilinxfb_platform_data pdata;
412 struct resource res;
413 int size, rc;
414 struct xilinxfb_drvdata *drvdata;
415
416 /* Copy with the default pdata (not a ptr reference!) */
417 pdata = xilinx_fb_default_pdata;
418
419 /* Allocate the driver data region */
420 drvdata = kzalloc(sizeof(*drvdata), GFP_KERNEL);
421 if (!drvdata) {
422 dev_err(&op->dev, "Couldn't allocate device private record\n");
423 return -ENOMEM;
424 }
425
426 /*
427 * To check whether the core is connected directly to DCR or PLB
428 * interface and initialize the tft_access accordingly.
429 */
430 p = (u32 *)of_get_property(op->dev.of_node, "xlnx,dcr-splb-slave-if", NULL);
431 tft_access = p ? *p : 0;
432
433 /*
434 * Fill the resource structure if its direct PLB interface
435 * otherwise fill the dcr_host structure.
436 */
437 if (tft_access) {
438 drvdata->flags |= PLB_ACCESS_FLAG;
439 rc = of_address_to_resource(op->dev.of_node, 0, &res);
440 if (rc) {
441 dev_err(&op->dev, "invalid address\n");
442 goto err;
443 }
444 }
445 #ifdef CONFIG_PPC_DCR
446 else {
447 int start;
448 res.start = 0;
449 start = dcr_resource_start(op->dev.of_node, 0);
450 drvdata->dcr_len = dcr_resource_len(op->dev.of_node, 0);
451 drvdata->dcr_host = dcr_map(op->dev.of_node, start, drvdata->dcr_len);
452 if (!DCR_MAP_OK(drvdata->dcr_host)) {
453 dev_err(&op->dev, "invalid DCR address\n");
454 goto err;
455 }
456 }
457 #endif
458
459 prop = of_get_property(op->dev.of_node, "phys-size", &size);
460 if ((prop) && (size >= sizeof(u32)*2)) {
461 pdata.screen_width_mm = prop[0];
462 pdata.screen_height_mm = prop[1];
463 }
464
465 prop = of_get_property(op->dev.of_node, "resolution", &size);
466 if ((prop) && (size >= sizeof(u32)*2)) {
467 pdata.xres = prop[0];
468 pdata.yres = prop[1];
469 }
470
471 prop = of_get_property(op->dev.of_node, "virtual-resolution", &size);
472 if ((prop) && (size >= sizeof(u32)*2)) {
473 pdata.xvirt = prop[0];
474 pdata.yvirt = prop[1];
475 }
476
477 if (of_find_property(op->dev.of_node, "rotate-display", NULL))
478 pdata.rotate_screen = 1;
479
480 dev_set_drvdata(&op->dev, drvdata);
481 return xilinxfb_assign(&op->dev, drvdata, res.start, &pdata);
482
483 err:
484 kfree(drvdata);
485 return -ENODEV;
486 }
487
xilinxfb_of_remove(struct platform_device * op)488 static int __devexit xilinxfb_of_remove(struct platform_device *op)
489 {
490 return xilinxfb_release(&op->dev);
491 }
492
493 /* Match table for of_platform binding */
494 static struct of_device_id xilinxfb_of_match[] __devinitdata = {
495 { .compatible = "xlnx,xps-tft-1.00.a", },
496 { .compatible = "xlnx,xps-tft-2.00.a", },
497 { .compatible = "xlnx,xps-tft-2.01.a", },
498 { .compatible = "xlnx,plb-tft-cntlr-ref-1.00.a", },
499 { .compatible = "xlnx,plb-dvi-cntlr-ref-1.00.c", },
500 {},
501 };
502 MODULE_DEVICE_TABLE(of, xilinxfb_of_match);
503
504 static struct platform_driver xilinxfb_of_driver = {
505 .probe = xilinxfb_of_probe,
506 .remove = __devexit_p(xilinxfb_of_remove),
507 .driver = {
508 .name = DRIVER_NAME,
509 .owner = THIS_MODULE,
510 .of_match_table = xilinxfb_of_match,
511 },
512 };
513
514 module_platform_driver(xilinxfb_of_driver);
515
516 MODULE_AUTHOR("MontaVista Software, Inc. <source@mvista.com>");
517 MODULE_DESCRIPTION("Xilinx TFT frame buffer driver");
518 MODULE_LICENSE("GPL");
519