xref: /openbmc/linux/drivers/gpu/drm/arm/hdlcd_drv.c (revision 5abbeebd)
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_generic.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 	struct resource *res;
104 	u32 version;
105 	int ret;
106 
107 	hdlcd->clk = devm_clk_get(drm->dev, "pxlclk");
108 	if (IS_ERR(hdlcd->clk))
109 		return PTR_ERR(hdlcd->clk);
110 
111 #ifdef CONFIG_DEBUG_FS
112 	atomic_set(&hdlcd->buffer_underrun_count, 0);
113 	atomic_set(&hdlcd->bus_error_count, 0);
114 	atomic_set(&hdlcd->vsync_count, 0);
115 	atomic_set(&hdlcd->dma_end_count, 0);
116 #endif
117 
118 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
119 	hdlcd->mmio = devm_ioremap_resource(drm->dev, res);
120 	if (IS_ERR(hdlcd->mmio)) {
121 		DRM_ERROR("failed to map control registers area\n");
122 		ret = PTR_ERR(hdlcd->mmio);
123 		hdlcd->mmio = NULL;
124 		return ret;
125 	}
126 
127 	version = hdlcd_read(hdlcd, HDLCD_REG_VERSION);
128 	if ((version & HDLCD_PRODUCT_MASK) != HDLCD_PRODUCT_ID) {
129 		DRM_ERROR("unknown product id: 0x%x\n", version);
130 		return -EINVAL;
131 	}
132 	DRM_INFO("found ARM HDLCD version r%dp%d\n",
133 		(version & HDLCD_VERSION_MAJOR_MASK) >> 8,
134 		version & HDLCD_VERSION_MINOR_MASK);
135 
136 	/* Get the optional framebuffer memory resource */
137 	ret = of_reserved_mem_device_init(drm->dev);
138 	if (ret && ret != -ENODEV)
139 		return ret;
140 
141 	ret = dma_set_mask_and_coherent(drm->dev, DMA_BIT_MASK(32));
142 	if (ret)
143 		goto setup_fail;
144 
145 	ret = hdlcd_setup_crtc(drm);
146 	if (ret < 0) {
147 		DRM_ERROR("failed to create crtc\n");
148 		goto setup_fail;
149 	}
150 
151 	ret = platform_get_irq(pdev, 0);
152 	if (ret < 0)
153 		goto irq_fail;
154 	hdlcd->irq = ret;
155 
156 	ret = hdlcd_irq_install(hdlcd);
157 	if (ret < 0) {
158 		DRM_ERROR("failed to install IRQ handler\n");
159 		goto irq_fail;
160 	}
161 
162 	return 0;
163 
164 irq_fail:
165 	drm_crtc_cleanup(&hdlcd->crtc);
166 setup_fail:
167 	of_reserved_mem_device_release(drm->dev);
168 
169 	return ret;
170 }
171 
172 static const struct drm_mode_config_funcs hdlcd_mode_config_funcs = {
173 	.fb_create = drm_gem_fb_create,
174 	.atomic_check = drm_atomic_helper_check,
175 	.atomic_commit = drm_atomic_helper_commit,
176 };
177 
178 static int hdlcd_setup_mode_config(struct drm_device *drm)
179 {
180 	int ret;
181 
182 	ret = drmm_mode_config_init(drm);
183 	if (ret)
184 		return ret;
185 
186 	drm->mode_config.min_width = 0;
187 	drm->mode_config.min_height = 0;
188 	drm->mode_config.max_width = HDLCD_MAX_XRES;
189 	drm->mode_config.max_height = HDLCD_MAX_YRES;
190 	drm->mode_config.funcs = &hdlcd_mode_config_funcs;
191 
192 	return 0;
193 }
194 
195 #ifdef CONFIG_DEBUG_FS
196 static int hdlcd_show_underrun_count(struct seq_file *m, void *arg)
197 {
198 	struct drm_info_node *node = (struct drm_info_node *)m->private;
199 	struct drm_device *drm = node->minor->dev;
200 	struct hdlcd_drm_private *hdlcd = drm_to_hdlcd_priv(drm);
201 
202 	seq_printf(m, "underrun : %d\n", atomic_read(&hdlcd->buffer_underrun_count));
203 	seq_printf(m, "dma_end  : %d\n", atomic_read(&hdlcd->dma_end_count));
204 	seq_printf(m, "bus_error: %d\n", atomic_read(&hdlcd->bus_error_count));
205 	seq_printf(m, "vsync    : %d\n", atomic_read(&hdlcd->vsync_count));
206 	return 0;
207 }
208 
209 static int hdlcd_show_pxlclock(struct seq_file *m, void *arg)
210 {
211 	struct drm_info_node *node = (struct drm_info_node *)m->private;
212 	struct drm_device *drm = node->minor->dev;
213 	struct hdlcd_drm_private *hdlcd = drm_to_hdlcd_priv(drm);
214 	unsigned long clkrate = clk_get_rate(hdlcd->clk);
215 	unsigned long mode_clock = hdlcd->crtc.mode.crtc_clock * 1000;
216 
217 	seq_printf(m, "hw  : %lu\n", clkrate);
218 	seq_printf(m, "mode: %lu\n", mode_clock);
219 	return 0;
220 }
221 
222 static struct drm_info_list hdlcd_debugfs_list[] = {
223 	{ "interrupt_count", hdlcd_show_underrun_count, 0 },
224 	{ "clocks", hdlcd_show_pxlclock, 0 },
225 };
226 
227 static void hdlcd_debugfs_init(struct drm_minor *minor)
228 {
229 	drm_debugfs_create_files(hdlcd_debugfs_list,
230 				 ARRAY_SIZE(hdlcd_debugfs_list),
231 				 minor->debugfs_root, minor);
232 }
233 #endif
234 
235 DEFINE_DRM_GEM_DMA_FOPS(fops);
236 
237 static const struct drm_driver hdlcd_driver = {
238 	.driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
239 	DRM_GEM_DMA_DRIVER_OPS,
240 #ifdef CONFIG_DEBUG_FS
241 	.debugfs_init = hdlcd_debugfs_init,
242 #endif
243 	.fops = &fops,
244 	.name = "hdlcd",
245 	.desc = "ARM HDLCD Controller DRM",
246 	.date = "20151021",
247 	.major = 1,
248 	.minor = 0,
249 };
250 
251 static int hdlcd_drm_bind(struct device *dev)
252 {
253 	struct drm_device *drm;
254 	struct hdlcd_drm_private *hdlcd;
255 	int ret;
256 
257 	hdlcd = devm_drm_dev_alloc(dev, &hdlcd_driver, typeof(*hdlcd), base);
258 	if (IS_ERR(hdlcd))
259 		return PTR_ERR(hdlcd);
260 
261 	drm = &hdlcd->base;
262 
263 	dev_set_drvdata(dev, drm);
264 
265 	ret = hdlcd_setup_mode_config(drm);
266 	if (ret)
267 		goto err_free;
268 
269 	ret = hdlcd_load(drm, 0);
270 	if (ret)
271 		goto err_free;
272 
273 	/* Set the CRTC's port so that the encoder component can find it */
274 	hdlcd->crtc.port = of_graph_get_port_by_id(dev->of_node, 0);
275 
276 	ret = component_bind_all(dev, drm);
277 	if (ret) {
278 		DRM_ERROR("Failed to bind all components\n");
279 		goto err_unload;
280 	}
281 
282 	ret = pm_runtime_set_active(dev);
283 	if (ret)
284 		goto err_pm_active;
285 
286 	pm_runtime_enable(dev);
287 
288 	ret = drm_vblank_init(drm, drm->mode_config.num_crtc);
289 	if (ret < 0) {
290 		DRM_ERROR("failed to initialise vblank\n");
291 		goto err_vblank;
292 	}
293 
294 	/*
295 	 * If EFI left us running, take over from simple framebuffer
296 	 * drivers. Read HDLCD_REG_COMMAND to see if we are enabled.
297 	 */
298 	if (hdlcd_read(hdlcd, HDLCD_REG_COMMAND)) {
299 		hdlcd_write(hdlcd, HDLCD_REG_COMMAND, 0);
300 		drm_aperture_remove_framebuffers(false, &hdlcd_driver);
301 	}
302 
303 	drm_mode_config_reset(drm);
304 	drm_kms_helper_poll_init(drm);
305 
306 	ret = drm_dev_register(drm, 0);
307 	if (ret)
308 		goto err_register;
309 
310 	drm_fbdev_generic_setup(drm, 32);
311 
312 	return 0;
313 
314 err_register:
315 	drm_kms_helper_poll_fini(drm);
316 err_vblank:
317 	pm_runtime_disable(drm->dev);
318 err_pm_active:
319 	drm_atomic_helper_shutdown(drm);
320 	component_unbind_all(dev, drm);
321 err_unload:
322 	of_node_put(hdlcd->crtc.port);
323 	hdlcd->crtc.port = NULL;
324 	hdlcd_irq_uninstall(hdlcd);
325 	of_reserved_mem_device_release(drm->dev);
326 err_free:
327 	dev_set_drvdata(dev, NULL);
328 	return ret;
329 }
330 
331 static void hdlcd_drm_unbind(struct device *dev)
332 {
333 	struct drm_device *drm = dev_get_drvdata(dev);
334 	struct hdlcd_drm_private *hdlcd = drm_to_hdlcd_priv(drm);
335 
336 	drm_dev_unregister(drm);
337 	drm_kms_helper_poll_fini(drm);
338 	component_unbind_all(dev, drm);
339 	of_node_put(hdlcd->crtc.port);
340 	hdlcd->crtc.port = NULL;
341 	pm_runtime_get_sync(dev);
342 	drm_atomic_helper_shutdown(drm);
343 	hdlcd_irq_uninstall(hdlcd);
344 	pm_runtime_put(dev);
345 	if (pm_runtime_enabled(dev))
346 		pm_runtime_disable(dev);
347 	of_reserved_mem_device_release(dev);
348 	dev_set_drvdata(dev, NULL);
349 }
350 
351 static const struct component_master_ops hdlcd_master_ops = {
352 	.bind		= hdlcd_drm_bind,
353 	.unbind		= hdlcd_drm_unbind,
354 };
355 
356 static int compare_dev(struct device *dev, void *data)
357 {
358 	return dev->of_node == data;
359 }
360 
361 static int hdlcd_probe(struct platform_device *pdev)
362 {
363 	struct device_node *port;
364 	struct component_match *match = NULL;
365 
366 	/* there is only one output port inside each device, find it */
367 	port = of_graph_get_remote_node(pdev->dev.of_node, 0, 0);
368 	if (!port)
369 		return -ENODEV;
370 
371 	drm_of_component_match_add(&pdev->dev, &match, compare_dev, port);
372 	of_node_put(port);
373 
374 	return component_master_add_with_match(&pdev->dev, &hdlcd_master_ops,
375 					       match);
376 }
377 
378 static int hdlcd_remove(struct platform_device *pdev)
379 {
380 	component_master_del(&pdev->dev, &hdlcd_master_ops);
381 	return 0;
382 }
383 
384 static const struct of_device_id  hdlcd_of_match[] = {
385 	{ .compatible	= "arm,hdlcd" },
386 	{},
387 };
388 MODULE_DEVICE_TABLE(of, hdlcd_of_match);
389 
390 static int __maybe_unused hdlcd_pm_suspend(struct device *dev)
391 {
392 	struct drm_device *drm = dev_get_drvdata(dev);
393 
394 	return drm_mode_config_helper_suspend(drm);
395 }
396 
397 static int __maybe_unused hdlcd_pm_resume(struct device *dev)
398 {
399 	struct drm_device *drm = dev_get_drvdata(dev);
400 
401 	drm_mode_config_helper_resume(drm);
402 
403 	return 0;
404 }
405 
406 static SIMPLE_DEV_PM_OPS(hdlcd_pm_ops, hdlcd_pm_suspend, hdlcd_pm_resume);
407 
408 static struct platform_driver hdlcd_platform_driver = {
409 	.probe		= hdlcd_probe,
410 	.remove		= hdlcd_remove,
411 	.driver	= {
412 		.name = "hdlcd",
413 		.pm = &hdlcd_pm_ops,
414 		.of_match_table	= hdlcd_of_match,
415 	},
416 };
417 
418 drm_module_platform_driver(hdlcd_platform_driver);
419 
420 MODULE_AUTHOR("Liviu Dudau");
421 MODULE_DESCRIPTION("ARM HDLCD DRM driver");
422 MODULE_LICENSE("GPL v2");
423