xref: /openbmc/linux/drivers/gpu/drm/arm/hdlcd_drv.c (revision bbaf1ff0)
1 /*
2  * Copyright (C) 2013-2015 ARM Limited
3  * Author: Liviu Dudau <Liviu.Dudau@arm.com>
4  *
5  * This file is subject to the terms and conditions of the GNU General Public
6  * License.  See the file COPYING in the main directory of this archive
7  * for more details.
8  *
9  *  ARM HDLCD Driver
10  */
11 
12 #include <linux/module.h>
13 #include <linux/spinlock.h>
14 #include <linux/clk.h>
15 #include <linux/component.h>
16 #include <linux/console.h>
17 #include <linux/dma-mapping.h>
18 #include <linux/list.h>
19 #include <linux/of_graph.h>
20 #include <linux/of_reserved_mem.h>
21 #include <linux/platform_device.h>
22 #include <linux/pm_runtime.h>
23 
24 #include <drm/drm_aperture.h>
25 #include <drm/drm_atomic_helper.h>
26 #include <drm/drm_crtc.h>
27 #include <drm/drm_debugfs.h>
28 #include <drm/drm_drv.h>
29 #include <drm/drm_fbdev_dma.h>
30 #include <drm/drm_gem_dma_helper.h>
31 #include <drm/drm_gem_framebuffer_helper.h>
32 #include <drm/drm_modeset_helper.h>
33 #include <drm/drm_module.h>
34 #include <drm/drm_of.h>
35 #include <drm/drm_probe_helper.h>
36 #include <drm/drm_vblank.h>
37 
38 #include "hdlcd_drv.h"
39 #include "hdlcd_regs.h"
40 
41 static irqreturn_t hdlcd_irq(int irq, void *arg)
42 {
43 	struct hdlcd_drm_private *hdlcd = arg;
44 	unsigned long irq_status;
45 
46 	irq_status = hdlcd_read(hdlcd, HDLCD_REG_INT_STATUS);
47 
48 #ifdef CONFIG_DEBUG_FS
49 	if (irq_status & HDLCD_INTERRUPT_UNDERRUN)
50 		atomic_inc(&hdlcd->buffer_underrun_count);
51 
52 	if (irq_status & HDLCD_INTERRUPT_DMA_END)
53 		atomic_inc(&hdlcd->dma_end_count);
54 
55 	if (irq_status & HDLCD_INTERRUPT_BUS_ERROR)
56 		atomic_inc(&hdlcd->bus_error_count);
57 
58 	if (irq_status & HDLCD_INTERRUPT_VSYNC)
59 		atomic_inc(&hdlcd->vsync_count);
60 
61 #endif
62 	if (irq_status & HDLCD_INTERRUPT_VSYNC)
63 		drm_crtc_handle_vblank(&hdlcd->crtc);
64 
65 	/* acknowledge interrupt(s) */
66 	hdlcd_write(hdlcd, HDLCD_REG_INT_CLEAR, irq_status);
67 
68 	return IRQ_HANDLED;
69 }
70 
71 static int hdlcd_irq_install(struct hdlcd_drm_private *hdlcd)
72 {
73 	int ret;
74 
75 	/* Ensure interrupts are disabled */
76 	hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, 0);
77 	hdlcd_write(hdlcd, HDLCD_REG_INT_CLEAR, ~0);
78 
79 	ret = request_irq(hdlcd->irq, hdlcd_irq, 0, "hdlcd", hdlcd);
80 	if (ret)
81 		return ret;
82 
83 #ifdef CONFIG_DEBUG_FS
84 	/* enable debug interrupts */
85 	hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, HDLCD_DEBUG_INT_MASK);
86 #endif
87 
88 	return 0;
89 }
90 
91 static void hdlcd_irq_uninstall(struct hdlcd_drm_private *hdlcd)
92 {
93 	/* disable all the interrupts that we might have enabled */
94 	hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, 0);
95 
96 	free_irq(hdlcd->irq, hdlcd);
97 }
98 
99 static int hdlcd_load(struct drm_device *drm, unsigned long flags)
100 {
101 	struct hdlcd_drm_private *hdlcd = drm_to_hdlcd_priv(drm);
102 	struct platform_device *pdev = to_platform_device(drm->dev);
103 	u32 version;
104 	int ret;
105 
106 	hdlcd->clk = devm_clk_get(drm->dev, "pxlclk");
107 	if (IS_ERR(hdlcd->clk))
108 		return PTR_ERR(hdlcd->clk);
109 
110 #ifdef CONFIG_DEBUG_FS
111 	atomic_set(&hdlcd->buffer_underrun_count, 0);
112 	atomic_set(&hdlcd->bus_error_count, 0);
113 	atomic_set(&hdlcd->vsync_count, 0);
114 	atomic_set(&hdlcd->dma_end_count, 0);
115 #endif
116 
117 	hdlcd->mmio = devm_platform_ioremap_resource(pdev, 0);
118 	if (IS_ERR(hdlcd->mmio)) {
119 		DRM_ERROR("failed to map control registers area\n");
120 		ret = PTR_ERR(hdlcd->mmio);
121 		hdlcd->mmio = NULL;
122 		return ret;
123 	}
124 
125 	version = hdlcd_read(hdlcd, HDLCD_REG_VERSION);
126 	if ((version & HDLCD_PRODUCT_MASK) != HDLCD_PRODUCT_ID) {
127 		DRM_ERROR("unknown product id: 0x%x\n", version);
128 		return -EINVAL;
129 	}
130 	DRM_INFO("found ARM HDLCD version r%dp%d\n",
131 		(version & HDLCD_VERSION_MAJOR_MASK) >> 8,
132 		version & HDLCD_VERSION_MINOR_MASK);
133 
134 	/* Get the optional framebuffer memory resource */
135 	ret = of_reserved_mem_device_init(drm->dev);
136 	if (ret && ret != -ENODEV)
137 		return ret;
138 
139 	ret = dma_set_mask_and_coherent(drm->dev, DMA_BIT_MASK(32));
140 	if (ret)
141 		goto setup_fail;
142 
143 	ret = hdlcd_setup_crtc(drm);
144 	if (ret < 0) {
145 		DRM_ERROR("failed to create crtc\n");
146 		goto setup_fail;
147 	}
148 
149 	ret = platform_get_irq(pdev, 0);
150 	if (ret < 0)
151 		goto irq_fail;
152 	hdlcd->irq = ret;
153 
154 	ret = hdlcd_irq_install(hdlcd);
155 	if (ret < 0) {
156 		DRM_ERROR("failed to install IRQ handler\n");
157 		goto irq_fail;
158 	}
159 
160 	return 0;
161 
162 irq_fail:
163 	drm_crtc_cleanup(&hdlcd->crtc);
164 setup_fail:
165 	of_reserved_mem_device_release(drm->dev);
166 
167 	return ret;
168 }
169 
170 static const struct drm_mode_config_funcs hdlcd_mode_config_funcs = {
171 	.fb_create = drm_gem_fb_create,
172 	.atomic_check = drm_atomic_helper_check,
173 	.atomic_commit = drm_atomic_helper_commit,
174 };
175 
176 static int hdlcd_setup_mode_config(struct drm_device *drm)
177 {
178 	int ret;
179 
180 	ret = drmm_mode_config_init(drm);
181 	if (ret)
182 		return ret;
183 
184 	drm->mode_config.min_width = 0;
185 	drm->mode_config.min_height = 0;
186 	drm->mode_config.max_width = HDLCD_MAX_XRES;
187 	drm->mode_config.max_height = HDLCD_MAX_YRES;
188 	drm->mode_config.funcs = &hdlcd_mode_config_funcs;
189 
190 	return 0;
191 }
192 
193 #ifdef CONFIG_DEBUG_FS
194 static int hdlcd_show_underrun_count(struct seq_file *m, void *arg)
195 {
196 	struct drm_debugfs_entry *entry = m->private;
197 	struct drm_device *drm = entry->dev;
198 	struct hdlcd_drm_private *hdlcd = drm_to_hdlcd_priv(drm);
199 
200 	seq_printf(m, "underrun : %d\n", atomic_read(&hdlcd->buffer_underrun_count));
201 	seq_printf(m, "dma_end  : %d\n", atomic_read(&hdlcd->dma_end_count));
202 	seq_printf(m, "bus_error: %d\n", atomic_read(&hdlcd->bus_error_count));
203 	seq_printf(m, "vsync    : %d\n", atomic_read(&hdlcd->vsync_count));
204 	return 0;
205 }
206 
207 static int hdlcd_show_pxlclock(struct seq_file *m, void *arg)
208 {
209 	struct drm_debugfs_entry *entry = m->private;
210 	struct drm_device *drm = entry->dev;
211 	struct hdlcd_drm_private *hdlcd = drm_to_hdlcd_priv(drm);
212 	unsigned long clkrate = clk_get_rate(hdlcd->clk);
213 	unsigned long mode_clock = hdlcd->crtc.mode.crtc_clock * 1000;
214 
215 	seq_printf(m, "hw  : %lu\n", clkrate);
216 	seq_printf(m, "mode: %lu\n", mode_clock);
217 	return 0;
218 }
219 
220 static struct drm_debugfs_info hdlcd_debugfs_list[] = {
221 	{ "interrupt_count", hdlcd_show_underrun_count, 0 },
222 	{ "clocks", hdlcd_show_pxlclock, 0 },
223 };
224 #endif
225 
226 DEFINE_DRM_GEM_DMA_FOPS(fops);
227 
228 static const struct drm_driver hdlcd_driver = {
229 	.driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
230 	DRM_GEM_DMA_DRIVER_OPS,
231 	.fops = &fops,
232 	.name = "hdlcd",
233 	.desc = "ARM HDLCD Controller DRM",
234 	.date = "20151021",
235 	.major = 1,
236 	.minor = 0,
237 };
238 
239 static int hdlcd_drm_bind(struct device *dev)
240 {
241 	struct drm_device *drm;
242 	struct hdlcd_drm_private *hdlcd;
243 	int ret;
244 
245 	hdlcd = devm_drm_dev_alloc(dev, &hdlcd_driver, typeof(*hdlcd), base);
246 	if (IS_ERR(hdlcd))
247 		return PTR_ERR(hdlcd);
248 
249 	drm = &hdlcd->base;
250 
251 	dev_set_drvdata(dev, drm);
252 
253 	ret = hdlcd_setup_mode_config(drm);
254 	if (ret)
255 		goto err_free;
256 
257 	ret = hdlcd_load(drm, 0);
258 	if (ret)
259 		goto err_free;
260 
261 	/* Set the CRTC's port so that the encoder component can find it */
262 	hdlcd->crtc.port = of_graph_get_port_by_id(dev->of_node, 0);
263 
264 	ret = component_bind_all(dev, drm);
265 	if (ret) {
266 		DRM_ERROR("Failed to bind all components\n");
267 		goto err_unload;
268 	}
269 
270 	ret = pm_runtime_set_active(dev);
271 	if (ret)
272 		goto err_pm_active;
273 
274 	pm_runtime_enable(dev);
275 
276 	ret = drm_vblank_init(drm, drm->mode_config.num_crtc);
277 	if (ret < 0) {
278 		DRM_ERROR("failed to initialise vblank\n");
279 		goto err_vblank;
280 	}
281 
282 	/*
283 	 * If EFI left us running, take over from simple framebuffer
284 	 * drivers. Read HDLCD_REG_COMMAND to see if we are enabled.
285 	 */
286 	if (hdlcd_read(hdlcd, HDLCD_REG_COMMAND)) {
287 		hdlcd_write(hdlcd, HDLCD_REG_COMMAND, 0);
288 		drm_aperture_remove_framebuffers(false, &hdlcd_driver);
289 	}
290 
291 	drm_mode_config_reset(drm);
292 	drm_kms_helper_poll_init(drm);
293 
294 #ifdef CONFIG_DEBUG_FS
295 	drm_debugfs_add_files(drm, hdlcd_debugfs_list, ARRAY_SIZE(hdlcd_debugfs_list));
296 #endif
297 
298 	ret = drm_dev_register(drm, 0);
299 	if (ret)
300 		goto err_register;
301 
302 	drm_fbdev_dma_setup(drm, 32);
303 
304 	return 0;
305 
306 err_register:
307 	drm_kms_helper_poll_fini(drm);
308 err_vblank:
309 	pm_runtime_disable(drm->dev);
310 err_pm_active:
311 	drm_atomic_helper_shutdown(drm);
312 	component_unbind_all(dev, drm);
313 err_unload:
314 	of_node_put(hdlcd->crtc.port);
315 	hdlcd->crtc.port = NULL;
316 	hdlcd_irq_uninstall(hdlcd);
317 	of_reserved_mem_device_release(drm->dev);
318 err_free:
319 	dev_set_drvdata(dev, NULL);
320 	return ret;
321 }
322 
323 static void hdlcd_drm_unbind(struct device *dev)
324 {
325 	struct drm_device *drm = dev_get_drvdata(dev);
326 	struct hdlcd_drm_private *hdlcd = drm_to_hdlcd_priv(drm);
327 
328 	drm_dev_unregister(drm);
329 	drm_kms_helper_poll_fini(drm);
330 	component_unbind_all(dev, drm);
331 	of_node_put(hdlcd->crtc.port);
332 	hdlcd->crtc.port = NULL;
333 	pm_runtime_get_sync(dev);
334 	drm_atomic_helper_shutdown(drm);
335 	hdlcd_irq_uninstall(hdlcd);
336 	pm_runtime_put(dev);
337 	if (pm_runtime_enabled(dev))
338 		pm_runtime_disable(dev);
339 	of_reserved_mem_device_release(dev);
340 	dev_set_drvdata(dev, NULL);
341 }
342 
343 static const struct component_master_ops hdlcd_master_ops = {
344 	.bind		= hdlcd_drm_bind,
345 	.unbind		= hdlcd_drm_unbind,
346 };
347 
348 static int compare_dev(struct device *dev, void *data)
349 {
350 	return dev->of_node == data;
351 }
352 
353 static int hdlcd_probe(struct platform_device *pdev)
354 {
355 	struct device_node *port;
356 	struct component_match *match = NULL;
357 
358 	/* there is only one output port inside each device, find it */
359 	port = of_graph_get_remote_node(pdev->dev.of_node, 0, 0);
360 	if (!port)
361 		return -ENODEV;
362 
363 	drm_of_component_match_add(&pdev->dev, &match, compare_dev, port);
364 	of_node_put(port);
365 
366 	return component_master_add_with_match(&pdev->dev, &hdlcd_master_ops,
367 					       match);
368 }
369 
370 static int hdlcd_remove(struct platform_device *pdev)
371 {
372 	component_master_del(&pdev->dev, &hdlcd_master_ops);
373 	return 0;
374 }
375 
376 static const struct of_device_id  hdlcd_of_match[] = {
377 	{ .compatible	= "arm,hdlcd" },
378 	{},
379 };
380 MODULE_DEVICE_TABLE(of, hdlcd_of_match);
381 
382 static int __maybe_unused hdlcd_pm_suspend(struct device *dev)
383 {
384 	struct drm_device *drm = dev_get_drvdata(dev);
385 
386 	return drm_mode_config_helper_suspend(drm);
387 }
388 
389 static int __maybe_unused hdlcd_pm_resume(struct device *dev)
390 {
391 	struct drm_device *drm = dev_get_drvdata(dev);
392 
393 	drm_mode_config_helper_resume(drm);
394 
395 	return 0;
396 }
397 
398 static SIMPLE_DEV_PM_OPS(hdlcd_pm_ops, hdlcd_pm_suspend, hdlcd_pm_resume);
399 
400 static struct platform_driver hdlcd_platform_driver = {
401 	.probe		= hdlcd_probe,
402 	.remove		= hdlcd_remove,
403 	.driver	= {
404 		.name = "hdlcd",
405 		.pm = &hdlcd_pm_ops,
406 		.of_match_table	= hdlcd_of_match,
407 	},
408 };
409 
410 drm_module_platform_driver(hdlcd_platform_driver);
411 
412 MODULE_AUTHOR("Liviu Dudau");
413 MODULE_DESCRIPTION("ARM HDLCD DRM driver");
414 MODULE_LICENSE("GPL v2");
415