xref: /openbmc/linux/drivers/gpu/drm/pl111/pl111_drv.c (revision 407e7517)
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 
64 #include <drm/drmP.h>
65 #include <drm/drm_atomic_helper.h>
66 #include <drm/drm_crtc_helper.h>
67 #include <drm/drm_gem_cma_helper.h>
68 #include <drm/drm_gem_framebuffer_helper.h>
69 #include <drm/drm_fb_helper.h>
70 #include <drm/drm_fb_cma_helper.h>
71 #include <drm/drm_of.h>
72 #include <drm/drm_bridge.h>
73 #include <drm/drm_panel.h>
74 
75 #include "pl111_drm.h"
76 #include "pl111_versatile.h"
77 
78 #define DRIVER_DESC      "DRM module for PL111"
79 
80 static const struct drm_mode_config_funcs mode_config_funcs = {
81 	.fb_create = drm_gem_fb_create,
82 	.atomic_check = drm_atomic_helper_check,
83 	.atomic_commit = drm_atomic_helper_commit,
84 };
85 
86 static int pl111_modeset_init(struct drm_device *dev)
87 {
88 	struct drm_mode_config *mode_config;
89 	struct pl111_drm_dev_private *priv = dev->dev_private;
90 	struct device_node *np = dev->dev->of_node;
91 	struct device_node *remote;
92 	struct drm_panel *panel = NULL;
93 	struct drm_bridge *bridge = NULL;
94 	bool defer = false;
95 	int ret = 0;
96 	int i;
97 
98 	drm_mode_config_init(dev);
99 	mode_config = &dev->mode_config;
100 	mode_config->funcs = &mode_config_funcs;
101 	mode_config->min_width = 1;
102 	mode_config->max_width = 1024;
103 	mode_config->min_height = 1;
104 	mode_config->max_height = 768;
105 
106 	i = 0;
107 	for_each_endpoint_of_node(np, remote) {
108 		struct drm_panel *tmp_panel;
109 		struct drm_bridge *tmp_bridge;
110 
111 		dev_dbg(dev->dev, "checking endpoint %d\n", i);
112 
113 		ret = drm_of_find_panel_or_bridge(dev->dev->of_node,
114 						  0, i,
115 						  &tmp_panel,
116 						  &tmp_bridge);
117 		if (ret) {
118 			if (ret == -EPROBE_DEFER) {
119 				/*
120 				 * Something deferred, but that is often just
121 				 * another way of saying -ENODEV, but let's
122 				 * cast a vote for later deferral.
123 				 */
124 				defer = true;
125 			} else if (ret != -ENODEV) {
126 				/* Continue, maybe something else is working */
127 				dev_err(dev->dev,
128 					"endpoint %d returns %d\n", i, ret);
129 			}
130 		}
131 
132 		if (tmp_panel) {
133 			dev_info(dev->dev,
134 				 "found panel on endpoint %d\n", i);
135 			panel = tmp_panel;
136 		}
137 		if (tmp_bridge) {
138 			dev_info(dev->dev,
139 				 "found bridge on endpoint %d\n", i);
140 			bridge = tmp_bridge;
141 		}
142 
143 		i++;
144 	}
145 
146 	/*
147 	 * If we can't find neither panel nor bridge on any of the
148 	 * endpoints, and any of them retured -EPROBE_DEFER, then
149 	 * let's defer this driver too.
150 	 */
151 	if ((!panel && !bridge) && defer)
152 		return -EPROBE_DEFER;
153 
154 	if (panel) {
155 		bridge = drm_panel_bridge_add(panel,
156 					      DRM_MODE_CONNECTOR_Unknown);
157 		if (IS_ERR(bridge)) {
158 			ret = PTR_ERR(bridge);
159 			goto out_config;
160 		}
161 	} else if (bridge) {
162 		dev_info(dev->dev, "Using non-panel bridge\n");
163 	} else {
164 		dev_err(dev->dev, "No bridge, exiting\n");
165 		return -ENODEV;
166 	}
167 
168 	priv->bridge = bridge;
169 	if (panel) {
170 		priv->panel = panel;
171 		priv->connector = panel->connector;
172 	}
173 
174 	ret = pl111_display_init(dev);
175 	if (ret != 0) {
176 		dev_err(dev->dev, "Failed to init display\n");
177 		goto out_bridge;
178 	}
179 
180 	ret = drm_simple_display_pipe_attach_bridge(&priv->pipe,
181 						    bridge);
182 	if (ret)
183 		return ret;
184 
185 	if (!priv->variant->broken_vblank) {
186 		ret = drm_vblank_init(dev, 1);
187 		if (ret != 0) {
188 			dev_err(dev->dev, "Failed to init vblank\n");
189 			goto out_bridge;
190 		}
191 	}
192 
193 	drm_mode_config_reset(dev);
194 
195 	drm_fb_cma_fbdev_init(dev, 32, 0);
196 
197 	drm_kms_helper_poll_init(dev);
198 
199 	goto finish;
200 
201 out_bridge:
202 	if (panel)
203 		drm_panel_bridge_remove(bridge);
204 out_config:
205 	drm_mode_config_cleanup(dev);
206 finish:
207 	return ret;
208 }
209 
210 DEFINE_DRM_GEM_CMA_FOPS(drm_fops);
211 
212 static struct drm_driver pl111_drm_driver = {
213 	.driver_features =
214 		DRIVER_MODESET | DRIVER_GEM | DRIVER_PRIME | DRIVER_ATOMIC,
215 	.lastclose = drm_fb_helper_lastclose,
216 	.ioctls = NULL,
217 	.fops = &drm_fops,
218 	.name = "pl111",
219 	.desc = DRIVER_DESC,
220 	.date = "20170317",
221 	.major = 1,
222 	.minor = 0,
223 	.patchlevel = 0,
224 	.dumb_create = drm_gem_cma_dumb_create,
225 	.gem_free_object_unlocked = drm_gem_cma_free_object,
226 	.gem_vm_ops = &drm_gem_cma_vm_ops,
227 	.prime_handle_to_fd = drm_gem_prime_handle_to_fd,
228 	.prime_fd_to_handle = drm_gem_prime_fd_to_handle,
229 	.gem_prime_import = drm_gem_prime_import,
230 	.gem_prime_import_sg_table = drm_gem_cma_prime_import_sg_table,
231 	.gem_prime_export = drm_gem_prime_export,
232 	.gem_prime_get_sg_table	= drm_gem_cma_prime_get_sg_table,
233 
234 #if defined(CONFIG_DEBUG_FS)
235 	.debugfs_init = pl111_debugfs_init,
236 #endif
237 };
238 
239 static int pl111_amba_probe(struct amba_device *amba_dev,
240 			    const struct amba_id *id)
241 {
242 	struct device *dev = &amba_dev->dev;
243 	struct pl111_drm_dev_private *priv;
244 	const struct pl111_variant_data *variant = id->data;
245 	struct drm_device *drm;
246 	int ret;
247 
248 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
249 	if (!priv)
250 		return -ENOMEM;
251 
252 	if (!variant->broken_vblank) {
253 		pl111_drm_driver.enable_vblank = pl111_enable_vblank;
254 		pl111_drm_driver.disable_vblank = pl111_disable_vblank;
255 	}
256 
257 	drm = drm_dev_alloc(&pl111_drm_driver, dev);
258 	if (IS_ERR(drm))
259 		return PTR_ERR(drm);
260 	amba_set_drvdata(amba_dev, drm);
261 	priv->drm = drm;
262 	drm->dev_private = priv;
263 	priv->variant = variant;
264 
265 	/* The two variants swap this register */
266 	if (variant->is_pl110) {
267 		priv->ienb = CLCD_PL110_IENB;
268 		priv->ctrl = CLCD_PL110_CNTL;
269 	} else {
270 		priv->ienb = CLCD_PL111_IENB;
271 		priv->ctrl = CLCD_PL111_CNTL;
272 	}
273 
274 	priv->regs = devm_ioremap_resource(dev, &amba_dev->res);
275 	if (IS_ERR(priv->regs)) {
276 		dev_err(dev, "%s failed mmio\n", __func__);
277 		return PTR_ERR(priv->regs);
278 	}
279 
280 	/* This may override some variant settings */
281 	ret = pl111_versatile_init(dev, priv);
282 	if (ret)
283 		goto dev_unref;
284 
285 	/* turn off interrupts before requesting the irq */
286 	writel(0, priv->regs + priv->ienb);
287 
288 	ret = devm_request_irq(dev, amba_dev->irq[0], pl111_irq, 0,
289 			       variant->name, priv);
290 	if (ret != 0) {
291 		dev_err(dev, "%s failed irq %d\n", __func__, ret);
292 		return ret;
293 	}
294 
295 	ret = pl111_modeset_init(drm);
296 	if (ret != 0)
297 		goto dev_unref;
298 
299 	ret = drm_dev_register(drm, 0);
300 	if (ret < 0)
301 		goto dev_unref;
302 
303 	return 0;
304 
305 dev_unref:
306 	drm_dev_unref(drm);
307 	return ret;
308 }
309 
310 static int pl111_amba_remove(struct amba_device *amba_dev)
311 {
312 	struct drm_device *drm = amba_get_drvdata(amba_dev);
313 	struct pl111_drm_dev_private *priv = drm->dev_private;
314 
315 	drm_dev_unregister(drm);
316 	drm_fb_cma_fbdev_fini(drm);
317 	if (priv->panel)
318 		drm_panel_bridge_remove(priv->bridge);
319 	drm_mode_config_cleanup(drm);
320 	drm_dev_unref(drm);
321 
322 	return 0;
323 }
324 
325 /*
326  * This early variant lacks the 565 and 444 pixel formats.
327  */
328 static const u32 pl110_pixel_formats[] = {
329 	DRM_FORMAT_ABGR8888,
330 	DRM_FORMAT_XBGR8888,
331 	DRM_FORMAT_ARGB8888,
332 	DRM_FORMAT_XRGB8888,
333 	DRM_FORMAT_ABGR1555,
334 	DRM_FORMAT_XBGR1555,
335 	DRM_FORMAT_ARGB1555,
336 	DRM_FORMAT_XRGB1555,
337 };
338 
339 static const struct pl111_variant_data pl110_variant = {
340 	.name = "PL110",
341 	.is_pl110 = true,
342 	.formats = pl110_pixel_formats,
343 	.nformats = ARRAY_SIZE(pl110_pixel_formats),
344 };
345 
346 /* RealView, Versatile Express etc use this modern variant */
347 static const u32 pl111_pixel_formats[] = {
348 	DRM_FORMAT_ABGR8888,
349 	DRM_FORMAT_XBGR8888,
350 	DRM_FORMAT_ARGB8888,
351 	DRM_FORMAT_XRGB8888,
352 	DRM_FORMAT_BGR565,
353 	DRM_FORMAT_RGB565,
354 	DRM_FORMAT_ABGR1555,
355 	DRM_FORMAT_XBGR1555,
356 	DRM_FORMAT_ARGB1555,
357 	DRM_FORMAT_XRGB1555,
358 	DRM_FORMAT_ABGR4444,
359 	DRM_FORMAT_XBGR4444,
360 	DRM_FORMAT_ARGB4444,
361 	DRM_FORMAT_XRGB4444,
362 };
363 
364 static const struct pl111_variant_data pl111_variant = {
365 	.name = "PL111",
366 	.formats = pl111_pixel_formats,
367 	.nformats = ARRAY_SIZE(pl111_pixel_formats),
368 };
369 
370 static const struct amba_id pl111_id_table[] = {
371 	{
372 		.id = 0x00041110,
373 		.mask = 0x000fffff,
374 		.data = (void*)&pl110_variant,
375 	},
376 	{
377 		.id = 0x00041111,
378 		.mask = 0x000fffff,
379 		.data = (void*)&pl111_variant,
380 	},
381 	{0, 0},
382 };
383 
384 static struct amba_driver pl111_amba_driver __maybe_unused = {
385 	.drv = {
386 		.name = "drm-clcd-pl111",
387 	},
388 	.probe = pl111_amba_probe,
389 	.remove = pl111_amba_remove,
390 	.id_table = pl111_id_table,
391 };
392 
393 #ifdef CONFIG_ARM_AMBA
394 module_amba_driver(pl111_amba_driver);
395 #endif
396 
397 MODULE_DESCRIPTION(DRIVER_DESC);
398 MODULE_AUTHOR("ARM Ltd.");
399 MODULE_LICENSE("GPL");
400