xref: /openbmc/linux/drivers/gpu/drm/pl111/pl111_drv.c (revision dc6a81c3)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * (C) COPYRIGHT 2012-2013 ARM Limited. All rights reserved.
4  *
5  * Parts of this file were based on sources as follows:
6  *
7  * Copyright (c) 2006-2008 Intel Corporation
8  * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
9  * Copyright (C) 2011 Texas Instruments
10  */
11 
12 /**
13  * DOC: ARM PrimeCell PL111 CLCD Driver
14  *
15  * The PL111 is a simple LCD controller that can support TFT and STN
16  * displays.  This driver exposes a standard KMS interface for them.
17  *
18  * This driver uses the same Device Tree binding as the fbdev CLCD
19  * driver.  While the fbdev driver supports panels that may be
20  * connected to the CLCD internally to the CLCD driver, in DRM the
21  * panels get split out to drivers/gpu/drm/panels/.  This means that,
22  * in converting from using fbdev to using DRM, you also need to write
23  * a panel driver (which may be as simple as an entry in
24  * panel-simple.c).
25  *
26  * The driver currently doesn't expose the cursor.  The DRM API for
27  * cursors requires support for 64x64 ARGB8888 cursor images, while
28  * the hardware can only support 64x64 monochrome with masking
29  * cursors.  While one could imagine trying to hack something together
30  * to look at the ARGB8888 and program reasonable in monochrome, we
31  * just don't expose the cursor at all instead, and leave cursor
32  * support to the X11 software cursor layer.
33  *
34  * TODO:
35  *
36  * - Fix race between setting plane base address and getting IRQ for
37  *   vsync firing the pageflip completion.
38  *
39  * - Use the "max-memory-bandwidth" DT property to filter the
40  *   supported formats.
41  *
42  * - Read back hardware state at boot to skip reprogramming the
43  *   hardware when doing a no-op modeset.
44  *
45  * - Use the CLKSEL bit to support switching between the two external
46  *   clock parents.
47  */
48 
49 #include <linux/amba/bus.h>
50 #include <linux/amba/clcd-regs.h>
51 #include <linux/dma-buf.h>
52 #include <linux/module.h>
53 #include <linux/of.h>
54 #include <linux/of_graph.h>
55 #include <linux/of_reserved_mem.h>
56 #include <linux/shmem_fs.h>
57 #include <linux/slab.h>
58 #include <linux/version.h>
59 
60 #include <drm/drm_atomic_helper.h>
61 #include <drm/drm_bridge.h>
62 #include <drm/drm_drv.h>
63 #include <drm/drm_fb_cma_helper.h>
64 #include <drm/drm_fb_helper.h>
65 #include <drm/drm_gem_cma_helper.h>
66 #include <drm/drm_gem_framebuffer_helper.h>
67 #include <drm/drm_of.h>
68 #include <drm/drm_panel.h>
69 #include <drm/drm_probe_helper.h>
70 #include <drm/drm_vblank.h>
71 
72 #include "pl111_drm.h"
73 #include "pl111_versatile.h"
74 #include "pl111_nomadik.h"
75 
76 #define DRIVER_DESC      "DRM module for PL111"
77 
78 static const struct drm_mode_config_funcs mode_config_funcs = {
79 	.fb_create = drm_gem_fb_create,
80 	.atomic_check = drm_atomic_helper_check,
81 	.atomic_commit = drm_atomic_helper_commit,
82 };
83 
84 static int pl111_modeset_init(struct drm_device *dev)
85 {
86 	struct drm_mode_config *mode_config;
87 	struct pl111_drm_dev_private *priv = dev->dev_private;
88 	struct device_node *np = dev->dev->of_node;
89 	struct device_node *remote;
90 	struct drm_panel *panel = NULL;
91 	struct drm_bridge *bridge = NULL;
92 	bool defer = false;
93 	int ret = 0;
94 	int i;
95 
96 	drm_mode_config_init(dev);
97 	mode_config = &dev->mode_config;
98 	mode_config->funcs = &mode_config_funcs;
99 	mode_config->min_width = 1;
100 	mode_config->max_width = 1024;
101 	mode_config->min_height = 1;
102 	mode_config->max_height = 768;
103 
104 	i = 0;
105 	for_each_endpoint_of_node(np, remote) {
106 		struct drm_panel *tmp_panel;
107 		struct drm_bridge *tmp_bridge;
108 
109 		dev_dbg(dev->dev, "checking endpoint %d\n", i);
110 
111 		ret = drm_of_find_panel_or_bridge(dev->dev->of_node,
112 						  0, i,
113 						  &tmp_panel,
114 						  &tmp_bridge);
115 		if (ret) {
116 			if (ret == -EPROBE_DEFER) {
117 				/*
118 				 * Something deferred, but that is often just
119 				 * another way of saying -ENODEV, but let's
120 				 * cast a vote for later deferral.
121 				 */
122 				defer = true;
123 			} else if (ret != -ENODEV) {
124 				/* Continue, maybe something else is working */
125 				dev_err(dev->dev,
126 					"endpoint %d returns %d\n", i, ret);
127 			}
128 		}
129 
130 		if (tmp_panel) {
131 			dev_info(dev->dev,
132 				 "found panel on endpoint %d\n", i);
133 			panel = tmp_panel;
134 		}
135 		if (tmp_bridge) {
136 			dev_info(dev->dev,
137 				 "found bridge on endpoint %d\n", i);
138 			bridge = tmp_bridge;
139 		}
140 
141 		i++;
142 	}
143 
144 	/*
145 	 * If we can't find neither panel nor bridge on any of the
146 	 * endpoints, and any of them retured -EPROBE_DEFER, then
147 	 * let's defer this driver too.
148 	 */
149 	if ((!panel && !bridge) && defer)
150 		return -EPROBE_DEFER;
151 
152 	if (panel) {
153 		bridge = drm_panel_bridge_add_typed(panel,
154 						    DRM_MODE_CONNECTOR_Unknown);
155 		if (IS_ERR(bridge)) {
156 			ret = PTR_ERR(bridge);
157 			goto out_config;
158 		}
159 	} else if (bridge) {
160 		dev_info(dev->dev, "Using non-panel bridge\n");
161 	} else {
162 		dev_err(dev->dev, "No bridge, exiting\n");
163 		return -ENODEV;
164 	}
165 
166 	priv->bridge = bridge;
167 	if (panel) {
168 		priv->panel = panel;
169 		priv->connector = drm_panel_bridge_connector(bridge);
170 	}
171 
172 	ret = pl111_display_init(dev);
173 	if (ret != 0) {
174 		dev_err(dev->dev, "Failed to init display\n");
175 		goto out_bridge;
176 	}
177 
178 	ret = drm_simple_display_pipe_attach_bridge(&priv->pipe,
179 						    bridge);
180 	if (ret)
181 		return ret;
182 
183 	if (!priv->variant->broken_vblank) {
184 		ret = drm_vblank_init(dev, 1);
185 		if (ret != 0) {
186 			dev_err(dev->dev, "Failed to init vblank\n");
187 			goto out_bridge;
188 		}
189 	}
190 
191 	drm_mode_config_reset(dev);
192 
193 	drm_kms_helper_poll_init(dev);
194 
195 	goto finish;
196 
197 out_bridge:
198 	if (panel)
199 		drm_panel_bridge_remove(bridge);
200 out_config:
201 	drm_mode_config_cleanup(dev);
202 finish:
203 	return ret;
204 }
205 
206 static struct drm_gem_object *
207 pl111_gem_import_sg_table(struct drm_device *dev,
208 			  struct dma_buf_attachment *attach,
209 			  struct sg_table *sgt)
210 {
211 	struct pl111_drm_dev_private *priv = dev->dev_private;
212 
213 	/*
214 	 * When using device-specific reserved memory we can't import
215 	 * DMA buffers: those are passed by reference in any global
216 	 * memory and we can only handle a specific range of memory.
217 	 */
218 	if (priv->use_device_memory)
219 		return ERR_PTR(-EINVAL);
220 
221 	return drm_gem_cma_prime_import_sg_table(dev, attach, sgt);
222 }
223 
224 DEFINE_DRM_GEM_CMA_FOPS(drm_fops);
225 
226 static struct drm_driver pl111_drm_driver = {
227 	.driver_features =
228 		DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC,
229 	.ioctls = NULL,
230 	.fops = &drm_fops,
231 	.name = "pl111",
232 	.desc = DRIVER_DESC,
233 	.date = "20170317",
234 	.major = 1,
235 	.minor = 0,
236 	.patchlevel = 0,
237 	.dumb_create = drm_gem_cma_dumb_create,
238 	.gem_free_object_unlocked = drm_gem_cma_free_object,
239 	.gem_vm_ops = &drm_gem_cma_vm_ops,
240 	.prime_handle_to_fd = drm_gem_prime_handle_to_fd,
241 	.prime_fd_to_handle = drm_gem_prime_fd_to_handle,
242 	.gem_prime_import_sg_table = pl111_gem_import_sg_table,
243 	.gem_prime_get_sg_table	= drm_gem_cma_prime_get_sg_table,
244 	.gem_prime_mmap = drm_gem_cma_prime_mmap,
245 	.gem_prime_vmap = drm_gem_cma_prime_vmap,
246 
247 #if defined(CONFIG_DEBUG_FS)
248 	.debugfs_init = pl111_debugfs_init,
249 #endif
250 };
251 
252 static int pl111_amba_probe(struct amba_device *amba_dev,
253 			    const struct amba_id *id)
254 {
255 	struct device *dev = &amba_dev->dev;
256 	struct pl111_drm_dev_private *priv;
257 	const struct pl111_variant_data *variant = id->data;
258 	struct drm_device *drm;
259 	int ret;
260 
261 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
262 	if (!priv)
263 		return -ENOMEM;
264 
265 	drm = drm_dev_alloc(&pl111_drm_driver, dev);
266 	if (IS_ERR(drm))
267 		return PTR_ERR(drm);
268 	amba_set_drvdata(amba_dev, drm);
269 	priv->drm = drm;
270 	drm->dev_private = priv;
271 	priv->variant = variant;
272 
273 	ret = of_reserved_mem_device_init(dev);
274 	if (!ret) {
275 		dev_info(dev, "using device-specific reserved memory\n");
276 		priv->use_device_memory = true;
277 	}
278 
279 	if (of_property_read_u32(dev->of_node, "max-memory-bandwidth",
280 				 &priv->memory_bw)) {
281 		dev_info(dev, "no max memory bandwidth specified, assume unlimited\n");
282 		priv->memory_bw = 0;
283 	}
284 
285 	/* The two main variants swap this register */
286 	if (variant->is_pl110 || variant->is_lcdc) {
287 		priv->ienb = CLCD_PL110_IENB;
288 		priv->ctrl = CLCD_PL110_CNTL;
289 	} else {
290 		priv->ienb = CLCD_PL111_IENB;
291 		priv->ctrl = CLCD_PL111_CNTL;
292 	}
293 
294 	priv->regs = devm_ioremap_resource(dev, &amba_dev->res);
295 	if (IS_ERR(priv->regs)) {
296 		dev_err(dev, "%s failed mmio\n", __func__);
297 		ret = PTR_ERR(priv->regs);
298 		goto dev_put;
299 	}
300 
301 	/* This may override some variant settings */
302 	ret = pl111_versatile_init(dev, priv);
303 	if (ret)
304 		goto dev_put;
305 
306 	pl111_nomadik_init(dev);
307 
308 	/* turn off interrupts before requesting the irq */
309 	writel(0, priv->regs + priv->ienb);
310 
311 	ret = devm_request_irq(dev, amba_dev->irq[0], pl111_irq, 0,
312 			       variant->name, priv);
313 	if (ret != 0) {
314 		dev_err(dev, "%s failed irq %d\n", __func__, ret);
315 		return ret;
316 	}
317 
318 	ret = pl111_modeset_init(drm);
319 	if (ret != 0)
320 		goto dev_put;
321 
322 	ret = drm_dev_register(drm, 0);
323 	if (ret < 0)
324 		goto dev_put;
325 
326 	drm_fbdev_generic_setup(drm, priv->variant->fb_bpp);
327 
328 	return 0;
329 
330 dev_put:
331 	drm_dev_put(drm);
332 	of_reserved_mem_device_release(dev);
333 
334 	return ret;
335 }
336 
337 static int pl111_amba_remove(struct amba_device *amba_dev)
338 {
339 	struct device *dev = &amba_dev->dev;
340 	struct drm_device *drm = amba_get_drvdata(amba_dev);
341 	struct pl111_drm_dev_private *priv = drm->dev_private;
342 
343 	drm_dev_unregister(drm);
344 	if (priv->panel)
345 		drm_panel_bridge_remove(priv->bridge);
346 	drm_mode_config_cleanup(drm);
347 	drm_dev_put(drm);
348 	of_reserved_mem_device_release(dev);
349 
350 	return 0;
351 }
352 
353 /*
354  * This early variant lacks the 565 and 444 pixel formats.
355  */
356 static const u32 pl110_pixel_formats[] = {
357 	DRM_FORMAT_ABGR8888,
358 	DRM_FORMAT_XBGR8888,
359 	DRM_FORMAT_ARGB8888,
360 	DRM_FORMAT_XRGB8888,
361 	DRM_FORMAT_ABGR1555,
362 	DRM_FORMAT_XBGR1555,
363 	DRM_FORMAT_ARGB1555,
364 	DRM_FORMAT_XRGB1555,
365 };
366 
367 static const struct pl111_variant_data pl110_variant = {
368 	.name = "PL110",
369 	.is_pl110 = true,
370 	.formats = pl110_pixel_formats,
371 	.nformats = ARRAY_SIZE(pl110_pixel_formats),
372 	.fb_bpp = 16,
373 };
374 
375 /* RealView, Versatile Express etc use this modern variant */
376 static const u32 pl111_pixel_formats[] = {
377 	DRM_FORMAT_ABGR8888,
378 	DRM_FORMAT_XBGR8888,
379 	DRM_FORMAT_ARGB8888,
380 	DRM_FORMAT_XRGB8888,
381 	DRM_FORMAT_BGR565,
382 	DRM_FORMAT_RGB565,
383 	DRM_FORMAT_ABGR1555,
384 	DRM_FORMAT_XBGR1555,
385 	DRM_FORMAT_ARGB1555,
386 	DRM_FORMAT_XRGB1555,
387 	DRM_FORMAT_ABGR4444,
388 	DRM_FORMAT_XBGR4444,
389 	DRM_FORMAT_ARGB4444,
390 	DRM_FORMAT_XRGB4444,
391 };
392 
393 static const struct pl111_variant_data pl111_variant = {
394 	.name = "PL111",
395 	.formats = pl111_pixel_formats,
396 	.nformats = ARRAY_SIZE(pl111_pixel_formats),
397 	.fb_bpp = 32,
398 };
399 
400 static const u32 pl110_nomadik_pixel_formats[] = {
401 	DRM_FORMAT_RGB888,
402 	DRM_FORMAT_BGR888,
403 	DRM_FORMAT_ABGR8888,
404 	DRM_FORMAT_XBGR8888,
405 	DRM_FORMAT_ARGB8888,
406 	DRM_FORMAT_XRGB8888,
407 	DRM_FORMAT_BGR565,
408 	DRM_FORMAT_RGB565,
409 	DRM_FORMAT_ABGR1555,
410 	DRM_FORMAT_XBGR1555,
411 	DRM_FORMAT_ARGB1555,
412 	DRM_FORMAT_XRGB1555,
413 	DRM_FORMAT_ABGR4444,
414 	DRM_FORMAT_XBGR4444,
415 	DRM_FORMAT_ARGB4444,
416 	DRM_FORMAT_XRGB4444,
417 };
418 
419 static const struct pl111_variant_data pl110_nomadik_variant = {
420 	.name = "LCDC (PL110 Nomadik)",
421 	.formats = pl110_nomadik_pixel_formats,
422 	.nformats = ARRAY_SIZE(pl110_nomadik_pixel_formats),
423 	.is_lcdc = true,
424 	.st_bitmux_control = true,
425 	.broken_vblank = true,
426 	.fb_bpp = 16,
427 };
428 
429 static const struct amba_id pl111_id_table[] = {
430 	{
431 		.id = 0x00041110,
432 		.mask = 0x000fffff,
433 		.data = (void *)&pl110_variant,
434 	},
435 	{
436 		.id = 0x00180110,
437 		.mask = 0x00fffffe,
438 		.data = (void *)&pl110_nomadik_variant,
439 	},
440 	{
441 		.id = 0x00041111,
442 		.mask = 0x000fffff,
443 		.data = (void *)&pl111_variant,
444 	},
445 	{0, 0},
446 };
447 
448 static struct amba_driver pl111_amba_driver __maybe_unused = {
449 	.drv = {
450 		.name = "drm-clcd-pl111",
451 	},
452 	.probe = pl111_amba_probe,
453 	.remove = pl111_amba_remove,
454 	.id_table = pl111_id_table,
455 };
456 
457 #ifdef CONFIG_ARM_AMBA
458 module_amba_driver(pl111_amba_driver);
459 #endif
460 
461 MODULE_DESCRIPTION(DRIVER_DESC);
462 MODULE_AUTHOR("ARM Ltd.");
463 MODULE_LICENSE("GPL");
464