xref: /openbmc/linux/drivers/gpu/drm/pl111/pl111_drv.c (revision faa16bc4)
1 /*
2  * (C) COPYRIGHT 2012-2013 ARM Limited. All rights reserved.
3  *
4  * Parts of this file were based on sources as follows:
5  *
6  * Copyright (c) 2006-2008 Intel Corporation
7  * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
8  * Copyright (C) 2011 Texas Instruments
9  *
10  * This program is free software and is provided to you under the terms of the
11  * GNU General Public License version 2 as published by the Free Software
12  * Foundation, and any use by you of this program is subject to the terms of
13  * such GNU licence.
14  *
15  */
16 
17 /**
18  * DOC: ARM PrimeCell PL111 CLCD Driver
19  *
20  * The PL111 is a simple LCD controller that can support TFT and STN
21  * displays.  This driver exposes a standard KMS interface for them.
22  *
23  * This driver uses the same Device Tree binding as the fbdev CLCD
24  * driver.  While the fbdev driver supports panels that may be
25  * connected to the CLCD internally to the CLCD driver, in DRM the
26  * panels get split out to drivers/gpu/drm/panels/.  This means that,
27  * in converting from using fbdev to using DRM, you also need to write
28  * a panel driver (which may be as simple as an entry in
29  * panel-simple.c).
30  *
31  * The driver currently doesn't expose the cursor.  The DRM API for
32  * cursors requires support for 64x64 ARGB8888 cursor images, while
33  * the hardware can only support 64x64 monochrome with masking
34  * cursors.  While one could imagine trying to hack something together
35  * to look at the ARGB8888 and program reasonable in monochrome, we
36  * just don't expose the cursor at all instead, and leave cursor
37  * support to the X11 software cursor layer.
38  *
39  * TODO:
40  *
41  * - Fix race between setting plane base address and getting IRQ for
42  *   vsync firing the pageflip completion.
43  *
44  * - Use the "max-memory-bandwidth" DT property to filter the
45  *   supported formats.
46  *
47  * - Read back hardware state at boot to skip reprogramming the
48  *   hardware when doing a no-op modeset.
49  *
50  * - Use the CLKSEL bit to support switching between the two external
51  *   clock parents.
52  */
53 
54 #include <linux/amba/bus.h>
55 #include <linux/amba/clcd-regs.h>
56 #include <linux/version.h>
57 #include <linux/shmem_fs.h>
58 #include <linux/dma-buf.h>
59 #include <linux/module.h>
60 #include <linux/slab.h>
61 #include <linux/of.h>
62 #include <linux/of_graph.h>
63 #include <linux/of_reserved_mem.h>
64 
65 #include <drm/drmP.h>
66 #include <drm/drm_atomic_helper.h>
67 #include <drm/drm_crtc_helper.h>
68 #include <drm/drm_gem_cma_helper.h>
69 #include <drm/drm_gem_framebuffer_helper.h>
70 #include <drm/drm_fb_helper.h>
71 #include <drm/drm_fb_cma_helper.h>
72 #include <drm/drm_of.h>
73 #include <drm/drm_bridge.h>
74 #include <drm/drm_panel.h>
75 
76 #include "pl111_drm.h"
77 #include "pl111_versatile.h"
78 
79 #define DRIVER_DESC      "DRM module for PL111"
80 
81 static const struct drm_mode_config_funcs mode_config_funcs = {
82 	.fb_create = drm_gem_fb_create,
83 	.atomic_check = drm_atomic_helper_check,
84 	.atomic_commit = drm_atomic_helper_commit,
85 };
86 
87 static int pl111_modeset_init(struct drm_device *dev)
88 {
89 	struct drm_mode_config *mode_config;
90 	struct pl111_drm_dev_private *priv = dev->dev_private;
91 	struct device_node *np = dev->dev->of_node;
92 	struct device_node *remote;
93 	struct drm_panel *panel = NULL;
94 	struct drm_bridge *bridge = NULL;
95 	bool defer = false;
96 	int ret = 0;
97 	int i;
98 
99 	drm_mode_config_init(dev);
100 	mode_config = &dev->mode_config;
101 	mode_config->funcs = &mode_config_funcs;
102 	mode_config->min_width = 1;
103 	mode_config->max_width = 1024;
104 	mode_config->min_height = 1;
105 	mode_config->max_height = 768;
106 
107 	i = 0;
108 	for_each_endpoint_of_node(np, remote) {
109 		struct drm_panel *tmp_panel;
110 		struct drm_bridge *tmp_bridge;
111 
112 		dev_dbg(dev->dev, "checking endpoint %d\n", i);
113 
114 		ret = drm_of_find_panel_or_bridge(dev->dev->of_node,
115 						  0, i,
116 						  &tmp_panel,
117 						  &tmp_bridge);
118 		if (ret) {
119 			if (ret == -EPROBE_DEFER) {
120 				/*
121 				 * Something deferred, but that is often just
122 				 * another way of saying -ENODEV, but let's
123 				 * cast a vote for later deferral.
124 				 */
125 				defer = true;
126 			} else if (ret != -ENODEV) {
127 				/* Continue, maybe something else is working */
128 				dev_err(dev->dev,
129 					"endpoint %d returns %d\n", i, ret);
130 			}
131 		}
132 
133 		if (tmp_panel) {
134 			dev_info(dev->dev,
135 				 "found panel on endpoint %d\n", i);
136 			panel = tmp_panel;
137 		}
138 		if (tmp_bridge) {
139 			dev_info(dev->dev,
140 				 "found bridge on endpoint %d\n", i);
141 			bridge = tmp_bridge;
142 		}
143 
144 		i++;
145 	}
146 
147 	/*
148 	 * If we can't find neither panel nor bridge on any of the
149 	 * endpoints, and any of them retured -EPROBE_DEFER, then
150 	 * let's defer this driver too.
151 	 */
152 	if ((!panel && !bridge) && defer)
153 		return -EPROBE_DEFER;
154 
155 	if (panel) {
156 		bridge = drm_panel_bridge_add(panel,
157 					      DRM_MODE_CONNECTOR_Unknown);
158 		if (IS_ERR(bridge)) {
159 			ret = PTR_ERR(bridge);
160 			goto out_config;
161 		}
162 	} else if (bridge) {
163 		dev_info(dev->dev, "Using non-panel bridge\n");
164 	} else {
165 		dev_err(dev->dev, "No bridge, exiting\n");
166 		return -ENODEV;
167 	}
168 
169 	priv->bridge = bridge;
170 	if (panel) {
171 		priv->panel = panel;
172 		priv->connector = panel->connector;
173 	}
174 
175 	ret = pl111_display_init(dev);
176 	if (ret != 0) {
177 		dev_err(dev->dev, "Failed to init display\n");
178 		goto out_bridge;
179 	}
180 
181 	ret = drm_simple_display_pipe_attach_bridge(&priv->pipe,
182 						    bridge);
183 	if (ret)
184 		return ret;
185 
186 	if (!priv->variant->broken_vblank) {
187 		ret = drm_vblank_init(dev, 1);
188 		if (ret != 0) {
189 			dev_err(dev->dev, "Failed to init vblank\n");
190 			goto out_bridge;
191 		}
192 	}
193 
194 	drm_mode_config_reset(dev);
195 
196 	drm_fb_cma_fbdev_init(dev, priv->variant->fb_bpp, 0);
197 
198 	drm_kms_helper_poll_init(dev);
199 
200 	goto finish;
201 
202 out_bridge:
203 	if (panel)
204 		drm_panel_bridge_remove(bridge);
205 out_config:
206 	drm_mode_config_cleanup(dev);
207 finish:
208 	return ret;
209 }
210 
211 static struct drm_gem_object *
212 pl111_gem_import_sg_table(struct drm_device *dev,
213 			  struct dma_buf_attachment *attach,
214 			  struct sg_table *sgt)
215 {
216 	struct pl111_drm_dev_private *priv = dev->dev_private;
217 
218 	/*
219 	 * When using device-specific reserved memory we can't import
220 	 * DMA buffers: those are passed by reference in any global
221 	 * memory and we can only handle a specific range of memory.
222 	 */
223 	if (priv->use_device_memory)
224 		return ERR_PTR(-EINVAL);
225 
226 	return drm_gem_cma_prime_import_sg_table(dev, attach, sgt);
227 }
228 
229 DEFINE_DRM_GEM_CMA_FOPS(drm_fops);
230 
231 static struct drm_driver pl111_drm_driver = {
232 	.driver_features =
233 		DRIVER_MODESET | DRIVER_GEM | DRIVER_PRIME | DRIVER_ATOMIC,
234 	.lastclose = drm_fb_helper_lastclose,
235 	.ioctls = NULL,
236 	.fops = &drm_fops,
237 	.name = "pl111",
238 	.desc = DRIVER_DESC,
239 	.date = "20170317",
240 	.major = 1,
241 	.minor = 0,
242 	.patchlevel = 0,
243 	.dumb_create = drm_gem_cma_dumb_create,
244 	.gem_free_object_unlocked = drm_gem_cma_free_object,
245 	.gem_vm_ops = &drm_gem_cma_vm_ops,
246 	.prime_handle_to_fd = drm_gem_prime_handle_to_fd,
247 	.prime_fd_to_handle = drm_gem_prime_fd_to_handle,
248 	.gem_prime_import = drm_gem_prime_import,
249 	.gem_prime_import_sg_table = pl111_gem_import_sg_table,
250 	.gem_prime_export = drm_gem_prime_export,
251 	.gem_prime_get_sg_table	= drm_gem_cma_prime_get_sg_table,
252 
253 #if defined(CONFIG_DEBUG_FS)
254 	.debugfs_init = pl111_debugfs_init,
255 #endif
256 };
257 
258 static int pl111_amba_probe(struct amba_device *amba_dev,
259 			    const struct amba_id *id)
260 {
261 	struct device *dev = &amba_dev->dev;
262 	struct pl111_drm_dev_private *priv;
263 	const struct pl111_variant_data *variant = id->data;
264 	struct drm_device *drm;
265 	int ret;
266 
267 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
268 	if (!priv)
269 		return -ENOMEM;
270 
271 	drm = drm_dev_alloc(&pl111_drm_driver, dev);
272 	if (IS_ERR(drm))
273 		return PTR_ERR(drm);
274 	amba_set_drvdata(amba_dev, drm);
275 	priv->drm = drm;
276 	drm->dev_private = priv;
277 	priv->variant = variant;
278 
279 	ret = of_reserved_mem_device_init(dev);
280 	if (!ret) {
281 		dev_info(dev, "using device-specific reserved memory\n");
282 		priv->use_device_memory = true;
283 	}
284 
285 	if (of_property_read_u32(dev->of_node, "max-memory-bandwidth",
286 				 &priv->memory_bw)) {
287 		dev_info(dev, "no max memory bandwidth specified, assume unlimited\n");
288 		priv->memory_bw = 0;
289 	}
290 
291 	/* The two variants swap this register */
292 	if (variant->is_pl110) {
293 		priv->ienb = CLCD_PL110_IENB;
294 		priv->ctrl = CLCD_PL110_CNTL;
295 	} else {
296 		priv->ienb = CLCD_PL111_IENB;
297 		priv->ctrl = CLCD_PL111_CNTL;
298 	}
299 
300 	priv->regs = devm_ioremap_resource(dev, &amba_dev->res);
301 	if (IS_ERR(priv->regs)) {
302 		dev_err(dev, "%s failed mmio\n", __func__);
303 		ret = PTR_ERR(priv->regs);
304 		goto dev_unref;
305 	}
306 
307 	/* This may override some variant settings */
308 	ret = pl111_versatile_init(dev, priv);
309 	if (ret)
310 		goto dev_unref;
311 
312 	/* turn off interrupts before requesting the irq */
313 	writel(0, priv->regs + priv->ienb);
314 
315 	ret = devm_request_irq(dev, amba_dev->irq[0], pl111_irq, 0,
316 			       variant->name, priv);
317 	if (ret != 0) {
318 		dev_err(dev, "%s failed irq %d\n", __func__, ret);
319 		return ret;
320 	}
321 
322 	ret = pl111_modeset_init(drm);
323 	if (ret != 0)
324 		goto dev_unref;
325 
326 	ret = drm_dev_register(drm, 0);
327 	if (ret < 0)
328 		goto dev_unref;
329 
330 	return 0;
331 
332 dev_unref:
333 	drm_dev_unref(drm);
334 	of_reserved_mem_device_release(dev);
335 
336 	return ret;
337 }
338 
339 static int pl111_amba_remove(struct amba_device *amba_dev)
340 {
341 	struct device *dev = &amba_dev->dev;
342 	struct drm_device *drm = amba_get_drvdata(amba_dev);
343 	struct pl111_drm_dev_private *priv = drm->dev_private;
344 
345 	drm_dev_unregister(drm);
346 	drm_fb_cma_fbdev_fini(drm);
347 	if (priv->panel)
348 		drm_panel_bridge_remove(priv->bridge);
349 	drm_mode_config_cleanup(drm);
350 	drm_dev_unref(drm);
351 	of_reserved_mem_device_release(dev);
352 
353 	return 0;
354 }
355 
356 /*
357  * This early variant lacks the 565 and 444 pixel formats.
358  */
359 static const u32 pl110_pixel_formats[] = {
360 	DRM_FORMAT_ABGR8888,
361 	DRM_FORMAT_XBGR8888,
362 	DRM_FORMAT_ARGB8888,
363 	DRM_FORMAT_XRGB8888,
364 	DRM_FORMAT_ABGR1555,
365 	DRM_FORMAT_XBGR1555,
366 	DRM_FORMAT_ARGB1555,
367 	DRM_FORMAT_XRGB1555,
368 };
369 
370 static const struct pl111_variant_data pl110_variant = {
371 	.name = "PL110",
372 	.is_pl110 = true,
373 	.formats = pl110_pixel_formats,
374 	.nformats = ARRAY_SIZE(pl110_pixel_formats),
375 	.fb_bpp = 16,
376 };
377 
378 /* RealView, Versatile Express etc use this modern variant */
379 static const u32 pl111_pixel_formats[] = {
380 	DRM_FORMAT_ABGR8888,
381 	DRM_FORMAT_XBGR8888,
382 	DRM_FORMAT_ARGB8888,
383 	DRM_FORMAT_XRGB8888,
384 	DRM_FORMAT_BGR565,
385 	DRM_FORMAT_RGB565,
386 	DRM_FORMAT_ABGR1555,
387 	DRM_FORMAT_XBGR1555,
388 	DRM_FORMAT_ARGB1555,
389 	DRM_FORMAT_XRGB1555,
390 	DRM_FORMAT_ABGR4444,
391 	DRM_FORMAT_XBGR4444,
392 	DRM_FORMAT_ARGB4444,
393 	DRM_FORMAT_XRGB4444,
394 };
395 
396 static const struct pl111_variant_data pl111_variant = {
397 	.name = "PL111",
398 	.formats = pl111_pixel_formats,
399 	.nformats = ARRAY_SIZE(pl111_pixel_formats),
400 	.fb_bpp = 32,
401 };
402 
403 static const struct amba_id pl111_id_table[] = {
404 	{
405 		.id = 0x00041110,
406 		.mask = 0x000fffff,
407 		.data = (void*)&pl110_variant,
408 	},
409 	{
410 		.id = 0x00041111,
411 		.mask = 0x000fffff,
412 		.data = (void*)&pl111_variant,
413 	},
414 	{0, 0},
415 };
416 
417 static struct amba_driver pl111_amba_driver __maybe_unused = {
418 	.drv = {
419 		.name = "drm-clcd-pl111",
420 	},
421 	.probe = pl111_amba_probe,
422 	.remove = pl111_amba_remove,
423 	.id_table = pl111_id_table,
424 };
425 
426 #ifdef CONFIG_ARM_AMBA
427 module_amba_driver(pl111_amba_driver);
428 #endif
429 
430 MODULE_DESCRIPTION(DRIVER_DESC);
431 MODULE_AUTHOR("ARM Ltd.");
432 MODULE_LICENSE("GPL");
433