1// SPDX-License-Identifier: GPL-2.0
2/*
3 * SH7760/SH7763 LCDC Framebuffer driver.
4 *
5 * (c) 2006-2008 MSC Vertriebsges.m.b.H.,
6 * Manuel Lauss <mano@roarinelk.homelinux.net>
7 * (c) 2008 Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
8 *
9 * PLEASE HAVE A LOOK AT Documentation/fb/sh7760fb.rst!
10 *
11 * Thanks to Siegfried Schaefer <s.schaefer at schaefer-edv.de>
12 * for his original source and testing!
13 *
14 * sh7760_setcolreg get from drivers/video/sh_mobile_lcdcfb.c
15 */
16
17#include <linux/completion.h>
18#include <linux/delay.h>
19#include <linux/dma-mapping.h>
20#include <linux/fb.h>
21#include <linux/interrupt.h>
22#include <linux/io.h>
23#include <linux/kernel.h>
24#include <linux/module.h>
25#include <linux/platform_device.h>
26#include <linux/slab.h>
27
28#include <asm/sh7760fb.h>
29
30struct sh7760fb_par {
31 void __iomem *base;
32 int irq;
33
34 struct sh7760fb_platdata *pd; /* display information */
35
36 dma_addr_t fbdma; /* physical address */
37
38 int rot; /* rotation enabled? */
39
40 u32 pseudo_palette[16];
41
42 struct platform_device *dev;
43 struct resource *ioarea;
44 struct completion vsync; /* vsync irq event */
45};
46
47static irqreturn_t sh7760fb_irq(int irq, void *data)
48{
49 struct completion *c = data;
50
51 complete(c);
52
53 return IRQ_HANDLED;
54}
55
56/* wait_for_lps - wait until power supply has reached a certain state. */
57static int wait_for_lps(struct sh7760fb_par *par, int val)
58{
59 int i = 100;
60 while (--i && ((ioread16(par->base + LDPMMR) & 3) != val))
61 msleep(msecs: 1);
62
63 if (i <= 0)
64 return -ETIMEDOUT;
65
66 return 0;
67}
68
69/* en/disable the LCDC */
70static int sh7760fb_blank(int blank, struct fb_info *info)
71{
72 struct sh7760fb_par *par = info->par;
73 struct sh7760fb_platdata *pd = par->pd;
74 unsigned short cntr = ioread16(par->base + LDCNTR);
75 unsigned short intr = ioread16(par->base + LDINTR);
76 int lps;
77
78 if (blank == FB_BLANK_UNBLANK) {
79 intr |= VINT_START;
80 cntr = LDCNTR_DON2 | LDCNTR_DON;
81 lps = 3;
82 } else {
83 intr &= ~VINT_START;
84 cntr = LDCNTR_DON2;
85 lps = 0;
86 }
87
88 if (pd->blank)
89 pd->blank(blank);
90
91 iowrite16(intr, par->base + LDINTR);
92 iowrite16(cntr, par->base + LDCNTR);
93
94 return wait_for_lps(par, val: lps);
95}
96
97static int sh7760_setcolreg (u_int regno,
98 u_int red, u_int green, u_int blue,
99 u_int transp, struct fb_info *info)
100{
101 u32 *palette = info->pseudo_palette;
102
103 if (regno >= 16)
104 return -EINVAL;
105
106 /* only FB_VISUAL_TRUECOLOR supported */
107
108 red >>= 16 - info->var.red.length;
109 green >>= 16 - info->var.green.length;
110 blue >>= 16 - info->var.blue.length;
111 transp >>= 16 - info->var.transp.length;
112
113 palette[regno] = (red << info->var.red.offset) |
114 (green << info->var.green.offset) |
115 (blue << info->var.blue.offset) |
116 (transp << info->var.transp.offset);
117
118 return 0;
119}
120
121static int sh7760fb_get_color_info(struct fb_info *info,
122 u16 lddfr, int *bpp, int *gray)
123{
124 int lbpp, lgray;
125
126 lgray = lbpp = 0;
127
128 switch (lddfr & LDDFR_COLOR_MASK) {
129 case LDDFR_1BPP_MONO:
130 lgray = 1;
131 lbpp = 1;
132 break;
133 case LDDFR_2BPP_MONO:
134 lgray = 1;
135 lbpp = 2;
136 break;
137 case LDDFR_4BPP_MONO:
138 lgray = 1;
139 fallthrough;
140 case LDDFR_4BPP:
141 lbpp = 4;
142 break;
143 case LDDFR_6BPP_MONO:
144 lgray = 1;
145 fallthrough;
146 case LDDFR_8BPP:
147 lbpp = 8;
148 break;
149 case LDDFR_16BPP_RGB555:
150 case LDDFR_16BPP_RGB565:
151 lbpp = 16;
152 lgray = 0;
153 break;
154 default:
155 fb_dbg(info, "unsupported LDDFR bit depth.\n");
156 return -EINVAL;
157 }
158
159 if (bpp)
160 *bpp = lbpp;
161 if (gray)
162 *gray = lgray;
163
164 return 0;
165}
166
167static int sh7760fb_check_var(struct fb_var_screeninfo *var,
168 struct fb_info *info)
169{
170 struct fb_fix_screeninfo *fix = &info->fix;
171 struct sh7760fb_par *par = info->par;
172 int ret, bpp;
173
174 /* get color info from register value */
175 ret = sh7760fb_get_color_info(info, lddfr: par->pd->lddfr, bpp: &bpp, NULL);
176 if (ret)
177 return ret;
178
179 var->bits_per_pixel = bpp;
180
181 if ((var->grayscale) && (var->bits_per_pixel == 1))
182 fix->visual = FB_VISUAL_MONO10;
183 else if (var->bits_per_pixel >= 15)
184 fix->visual = FB_VISUAL_TRUECOLOR;
185 else
186 fix->visual = FB_VISUAL_PSEUDOCOLOR;
187
188 /* TODO: add some more validation here */
189 return 0;
190}
191
192/*
193 * sh7760fb_set_par - set videomode.
194 *
195 * NOTE: The rotation, grayscale and DSTN codepaths are
196 * totally untested!
197 */
198static int sh7760fb_set_par(struct fb_info *info)
199{
200 struct sh7760fb_par *par = info->par;
201 struct fb_videomode *vm = par->pd->def_mode;
202 unsigned long sbase, dstn_off, ldsarl, stride;
203 unsigned short hsynp, hsynw, htcn, hdcn;
204 unsigned short vsynp, vsynw, vtln, vdln;
205 unsigned short lddfr, ldmtr;
206 int ret, bpp, gray;
207
208 par->rot = par->pd->rotate;
209
210 /* rotate only works with xres <= 320 */
211 if (par->rot && (vm->xres > 320)) {
212 fb_dbg(info, "rotation disabled due to display size\n");
213 par->rot = 0;
214 }
215
216 /* calculate LCDC reg vals from display parameters */
217 hsynp = vm->right_margin + vm->xres;
218 hsynw = vm->hsync_len;
219 htcn = vm->left_margin + hsynp + hsynw;
220 hdcn = vm->xres;
221 vsynp = vm->lower_margin + vm->yres;
222 vsynw = vm->vsync_len;
223 vtln = vm->upper_margin + vsynp + vsynw;
224 vdln = vm->yres;
225
226 /* get color info from register value */
227 ret = sh7760fb_get_color_info(info, lddfr: par->pd->lddfr, bpp: &bpp, gray: &gray);
228 if (ret)
229 return ret;
230
231 fb_dbg(info, "%dx%d %dbpp %s (orientation %s)\n", hdcn,
232 vdln, bpp, gray ? "grayscale" : "color",
233 par->rot ? "rotated" : "normal");
234
235#ifdef CONFIG_CPU_LITTLE_ENDIAN
236 lddfr = par->pd->lddfr | (1 << 8);
237#else
238 lddfr = par->pd->lddfr & ~(1 << 8);
239#endif
240
241 ldmtr = par->pd->ldmtr;
242
243 if (!(vm->sync & FB_SYNC_HOR_HIGH_ACT))
244 ldmtr |= LDMTR_CL1POL;
245 if (!(vm->sync & FB_SYNC_VERT_HIGH_ACT))
246 ldmtr |= LDMTR_FLMPOL;
247
248 /* shut down LCDC before changing display parameters */
249 sh7760fb_blank(blank: FB_BLANK_POWERDOWN, info);
250
251 iowrite16(par->pd->ldickr, par->base + LDICKR); /* pixclock */
252 iowrite16(ldmtr, par->base + LDMTR); /* polarities */
253 iowrite16(lddfr, par->base + LDDFR); /* color/depth */
254 iowrite16((par->rot ? 1 << 13 : 0), par->base + LDSMR); /* rotate */
255 iowrite16(par->pd->ldpmmr, par->base + LDPMMR); /* Power Management */
256 iowrite16(par->pd->ldpspr, par->base + LDPSPR); /* Power Supply Ctrl */
257
258 /* display resolution */
259 iowrite16(((htcn >> 3) - 1) | (((hdcn >> 3) - 1) << 8),
260 par->base + LDHCNR);
261 iowrite16(vdln - 1, par->base + LDVDLNR);
262 iowrite16(vtln - 1, par->base + LDVTLNR);
263 /* h/v sync signals */
264 iowrite16((vsynp - 1) | ((vsynw - 1) << 12), par->base + LDVSYNR);
265 iowrite16(((hsynp >> 3) - 1) | (((hsynw >> 3) - 1) << 12),
266 par->base + LDHSYNR);
267 /* AC modulation sig */
268 iowrite16(par->pd->ldaclnr, par->base + LDACLNR);
269
270 stride = (par->rot) ? vtln : hdcn;
271 if (!gray)
272 stride *= (bpp + 7) >> 3;
273 else {
274 if (bpp == 1)
275 stride >>= 3;
276 else if (bpp == 2)
277 stride >>= 2;
278 else if (bpp == 4)
279 stride >>= 1;
280 /* 6 bpp == 8 bpp */
281 }
282
283 /* if rotated, stride must be power of 2 */
284 if (par->rot) {
285 unsigned long bit = 1 << 31;
286 while (bit) {
287 if (stride & bit)
288 break;
289 bit >>= 1;
290 }
291 if (stride & ~bit)
292 stride = bit << 1; /* not P-o-2, round up */
293 }
294 iowrite16(stride, par->base + LDLAOR);
295
296 /* set display mem start address */
297 sbase = (unsigned long)par->fbdma;
298 if (par->rot)
299 sbase += (hdcn - 1) * stride;
300
301 iowrite32(sbase, par->base + LDSARU);
302
303 /*
304 * for DSTN need to set address for lower half.
305 * I (mlau) don't know which address to set it to,
306 * so I guessed at (stride * yres/2).
307 */
308 if (((ldmtr & 0x003f) >= LDMTR_DSTN_MONO_8) &&
309 ((ldmtr & 0x003f) <= LDMTR_DSTN_COLOR_16)) {
310
311 fb_dbg(info, " ***** DSTN untested! *****\n");
312
313 dstn_off = stride;
314 if (par->rot)
315 dstn_off *= hdcn >> 1;
316 else
317 dstn_off *= vdln >> 1;
318
319 ldsarl = sbase + dstn_off;
320 } else
321 ldsarl = 0;
322
323 iowrite32(ldsarl, par->base + LDSARL); /* mem for lower half of DSTN */
324
325 info->fix.line_length = stride;
326
327 sh7760fb_check_var(var: &info->var, info);
328
329 sh7760fb_blank(blank: FB_BLANK_UNBLANK, info); /* panel on! */
330
331 fb_dbg(info, "hdcn : %6d htcn : %6d\n", hdcn, htcn);
332 fb_dbg(info, "hsynw : %6d hsynp : %6d\n", hsynw, hsynp);
333 fb_dbg(info, "vdln : %6d vtln : %6d\n", vdln, vtln);
334 fb_dbg(info, "vsynw : %6d vsynp : %6d\n", vsynw, vsynp);
335 fb_dbg(info, "clksrc: %6d clkdiv: %6d\n",
336 (par->pd->ldickr >> 12) & 3, par->pd->ldickr & 0x1f);
337 fb_dbg(info, "ldpmmr: 0x%04x ldpspr: 0x%04x\n", par->pd->ldpmmr,
338 par->pd->ldpspr);
339 fb_dbg(info, "ldmtr : 0x%04x lddfr : 0x%04x\n", ldmtr, lddfr);
340 fb_dbg(info, "ldlaor: %ld\n", stride);
341 fb_dbg(info, "ldsaru: 0x%08lx ldsarl: 0x%08lx\n", sbase, ldsarl);
342
343 return 0;
344}
345
346static const struct fb_ops sh7760fb_ops = {
347 .owner = THIS_MODULE,
348 FB_DEFAULT_IOMEM_OPS,
349 .fb_blank = sh7760fb_blank,
350 .fb_check_var = sh7760fb_check_var,
351 .fb_setcolreg = sh7760_setcolreg,
352 .fb_set_par = sh7760fb_set_par,
353};
354
355static void sh7760fb_free_mem(struct fb_info *info)
356{
357 struct sh7760fb_par *par = info->par;
358
359 if (!info->screen_base)
360 return;
361
362 dma_free_coherent(dev: info->device, size: info->screen_size,
363 cpu_addr: info->screen_base, dma_handle: par->fbdma);
364
365 par->fbdma = 0;
366 info->screen_base = NULL;
367 info->screen_size = 0;
368}
369
370/* allocate the framebuffer memory. This memory must be in Area3,
371 * (dictated by the DMA engine) and contiguous, at a 512 byte boundary.
372 */
373static int sh7760fb_alloc_mem(struct fb_info *info)
374{
375 struct sh7760fb_par *par = info->par;
376 void *fbmem;
377 unsigned long vram;
378 int ret, bpp;
379
380 if (info->screen_base)
381 return 0;
382
383 /* get color info from register value */
384 ret = sh7760fb_get_color_info(info, lddfr: par->pd->lddfr, bpp: &bpp, NULL);
385 if (ret) {
386 printk(KERN_ERR "colinfo\n");
387 return ret;
388 }
389
390 /* min VRAM: xres_min = 16, yres_min = 1, bpp = 1: 2byte -> 1 page
391 max VRAM: xres_max = 1024, yres_max = 1024, bpp = 16: 2MB */
392
393 vram = info->var.xres * info->var.yres;
394 if (info->var.grayscale) {
395 if (bpp == 1)
396 vram >>= 3;
397 else if (bpp == 2)
398 vram >>= 2;
399 else if (bpp == 4)
400 vram >>= 1;
401 } else if (bpp > 8)
402 vram *= 2;
403 if ((vram < 1) || (vram > 1024 * 2048)) {
404 fb_dbg(info, "too much VRAM required. Check settings\n");
405 return -ENODEV;
406 }
407
408 if (vram < PAGE_SIZE)
409 vram = PAGE_SIZE;
410
411 fbmem = dma_alloc_coherent(dev: info->device, size: vram, dma_handle: &par->fbdma, GFP_KERNEL);
412
413 if (!fbmem)
414 return -ENOMEM;
415
416 if ((par->fbdma & SH7760FB_DMA_MASK) != SH7760FB_DMA_MASK) {
417 sh7760fb_free_mem(info);
418 dev_err(info->device, "kernel gave me memory at 0x%08lx, which is"
419 "unusable for the LCDC\n", (unsigned long)par->fbdma);
420 return -ENOMEM;
421 }
422
423 info->screen_base = fbmem;
424 info->screen_size = vram;
425 info->fix.smem_start = (unsigned long)info->screen_base;
426 info->fix.smem_len = info->screen_size;
427
428 return 0;
429}
430
431static int sh7760fb_probe(struct platform_device *pdev)
432{
433 struct fb_info *info;
434 struct resource *res;
435 struct sh7760fb_par *par;
436 int ret;
437
438 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
439 if (unlikely(res == NULL)) {
440 dev_err(&pdev->dev, "invalid resource\n");
441 return -EINVAL;
442 }
443
444 info = framebuffer_alloc(size: sizeof(struct sh7760fb_par), dev: &pdev->dev);
445 if (!info)
446 return -ENOMEM;
447
448 par = info->par;
449 par->dev = pdev;
450
451 par->pd = pdev->dev.platform_data;
452 if (!par->pd) {
453 dev_dbg(&pdev->dev, "no display setup data!\n");
454 ret = -ENODEV;
455 goto out_fb;
456 }
457
458 par->ioarea = request_mem_region(res->start,
459 resource_size(res), pdev->name);
460 if (!par->ioarea) {
461 dev_err(&pdev->dev, "mmio area busy\n");
462 ret = -EBUSY;
463 goto out_fb;
464 }
465
466 par->base = ioremap(offset: res->start, size: resource_size(res));
467 if (!par->base) {
468 dev_err(&pdev->dev, "cannot remap\n");
469 ret = -ENODEV;
470 goto out_res;
471 }
472
473 iowrite16(0, par->base + LDINTR); /* disable vsync irq */
474 par->irq = platform_get_irq(pdev, 0);
475 if (par->irq >= 0) {
476 ret = request_irq(irq: par->irq, handler: sh7760fb_irq, flags: 0,
477 name: "sh7760-lcdc", dev: &par->vsync);
478 if (ret) {
479 dev_err(&pdev->dev, "cannot grab IRQ\n");
480 par->irq = -ENXIO;
481 } else
482 disable_irq_nosync(irq: par->irq);
483 }
484
485 fb_videomode_to_var(var: &info->var, mode: par->pd->def_mode);
486
487 ret = sh7760fb_alloc_mem(info);
488 if (ret) {
489 dev_dbg(info->device, "framebuffer memory allocation failed!\n");
490 goto out_unmap;
491 }
492
493 info->pseudo_palette = par->pseudo_palette;
494
495 /* fixup color register bitpositions. These are fixed by hardware */
496 info->var.red.offset = 11;
497 info->var.red.length = 5;
498 info->var.red.msb_right = 0;
499
500 info->var.green.offset = 5;
501 info->var.green.length = 6;
502 info->var.green.msb_right = 0;
503
504 info->var.blue.offset = 0;
505 info->var.blue.length = 5;
506 info->var.blue.msb_right = 0;
507
508 info->var.transp.offset = 0;
509 info->var.transp.length = 0;
510 info->var.transp.msb_right = 0;
511
512 strcpy(p: info->fix.id, q: "sh7760-lcdc");
513
514 /* set the DON2 bit now, before cmap allocation, as it will randomize
515 * palette memory.
516 */
517 iowrite16(LDCNTR_DON2, par->base + LDCNTR);
518 info->fbops = &sh7760fb_ops;
519
520 ret = fb_alloc_cmap(cmap: &info->cmap, len: 256, transp: 0);
521 if (ret) {
522 dev_dbg(&pdev->dev, "Unable to allocate cmap memory\n");
523 goto out_mem;
524 }
525
526 ret = register_framebuffer(fb_info: info);
527 if (ret < 0) {
528 dev_dbg(&pdev->dev, "cannot register fb!\n");
529 goto out_cmap;
530 }
531 platform_set_drvdata(pdev, data: info);
532
533 printk(KERN_INFO "%s: memory at phys 0x%08lx-0x%08lx, size %ld KiB\n",
534 pdev->name,
535 (unsigned long)par->fbdma,
536 (unsigned long)(par->fbdma + info->screen_size - 1),
537 info->screen_size >> 10);
538
539 return 0;
540
541out_cmap:
542 sh7760fb_blank(blank: FB_BLANK_POWERDOWN, info);
543 fb_dealloc_cmap(cmap: &info->cmap);
544out_mem:
545 sh7760fb_free_mem(info);
546out_unmap:
547 if (par->irq >= 0)
548 free_irq(par->irq, &par->vsync);
549 iounmap(addr: par->base);
550out_res:
551 release_mem_region(res->start, resource_size(res));
552out_fb:
553 framebuffer_release(info);
554 return ret;
555}
556
557static void sh7760fb_remove(struct platform_device *dev)
558{
559 struct fb_info *info = platform_get_drvdata(pdev: dev);
560 struct sh7760fb_par *par = info->par;
561
562 sh7760fb_blank(blank: FB_BLANK_POWERDOWN, info);
563 unregister_framebuffer(fb_info: info);
564 fb_dealloc_cmap(cmap: &info->cmap);
565 sh7760fb_free_mem(info);
566 if (par->irq >= 0)
567 free_irq(par->irq, &par->vsync);
568 iounmap(addr: par->base);
569 release_mem_region(par->ioarea->start, resource_size(par->ioarea));
570 framebuffer_release(info);
571}
572
573static struct platform_driver sh7760_lcdc_driver = {
574 .driver = {
575 .name = "sh7760-lcdc",
576 },
577 .probe = sh7760fb_probe,
578 .remove_new = sh7760fb_remove,
579};
580
581module_platform_driver(sh7760_lcdc_driver);
582
583MODULE_AUTHOR("Nobuhiro Iwamatsu, Manuel Lauss");
584MODULE_DESCRIPTION("FBdev for SH7760/63 integrated LCD Controller");
585MODULE_LICENSE("GPL v2");
586

source code of linux/drivers/video/fbdev/sh7760fb.c