xref: /openbmc/linux/drivers/gpu/drm/arm/hdlcd_drv.c (revision f33ac92f)
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_atomic_helper.h>
25 #include <drm/drm_crtc.h>
26 #include <drm/drm_debugfs.h>
27 #include <drm/drm_drv.h>
28 #include <drm/drm_fb_cma_helper.h>
29 #include <drm/drm_fb_helper.h>
30 #include <drm/drm_gem_cma_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 drm_device *drm = arg;
44 	struct hdlcd_drm_private *hdlcd = drm->dev_private;
45 	unsigned long irq_status;
46 
47 	irq_status = hdlcd_read(hdlcd, HDLCD_REG_INT_STATUS);
48 
49 #ifdef CONFIG_DEBUG_FS
50 	if (irq_status & HDLCD_INTERRUPT_UNDERRUN)
51 		atomic_inc(&hdlcd->buffer_underrun_count);
52 
53 	if (irq_status & HDLCD_INTERRUPT_DMA_END)
54 		atomic_inc(&hdlcd->dma_end_count);
55 
56 	if (irq_status & HDLCD_INTERRUPT_BUS_ERROR)
57 		atomic_inc(&hdlcd->bus_error_count);
58 
59 	if (irq_status & HDLCD_INTERRUPT_VSYNC)
60 		atomic_inc(&hdlcd->vsync_count);
61 
62 #endif
63 	if (irq_status & HDLCD_INTERRUPT_VSYNC)
64 		drm_crtc_handle_vblank(&hdlcd->crtc);
65 
66 	/* acknowledge interrupt(s) */
67 	hdlcd_write(hdlcd, HDLCD_REG_INT_CLEAR, irq_status);
68 
69 	return IRQ_HANDLED;
70 }
71 
72 static void hdlcd_irq_preinstall(struct drm_device *drm)
73 {
74 	struct hdlcd_drm_private *hdlcd = drm->dev_private;
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 
80 static void hdlcd_irq_postinstall(struct drm_device *drm)
81 {
82 #ifdef CONFIG_DEBUG_FS
83 	struct hdlcd_drm_private *hdlcd = drm->dev_private;
84 	unsigned long irq_mask = hdlcd_read(hdlcd, HDLCD_REG_INT_MASK);
85 
86 	/* enable debug interrupts */
87 	irq_mask |= HDLCD_DEBUG_INT_MASK;
88 
89 	hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, irq_mask);
90 #endif
91 }
92 
93 static int hdlcd_irq_install(struct drm_device *drm, int irq)
94 {
95 	int ret;
96 
97 	if (irq == IRQ_NOTCONNECTED)
98 		return -ENOTCONN;
99 
100 	hdlcd_irq_preinstall(drm);
101 
102 	ret = request_irq(irq, hdlcd_irq, 0, drm->driver->name, drm);
103 	if (ret)
104 		return ret;
105 
106 	hdlcd_irq_postinstall(drm);
107 
108 	return 0;
109 }
110 
111 static void hdlcd_irq_uninstall(struct drm_device *drm)
112 {
113 	struct hdlcd_drm_private *hdlcd = drm->dev_private;
114 	/* disable all the interrupts that we might have enabled */
115 	unsigned long irq_mask = hdlcd_read(hdlcd, HDLCD_REG_INT_MASK);
116 
117 #ifdef CONFIG_DEBUG_FS
118 	/* disable debug interrupts */
119 	irq_mask &= ~HDLCD_DEBUG_INT_MASK;
120 #endif
121 
122 	/* disable vsync interrupts */
123 	irq_mask &= ~HDLCD_INTERRUPT_VSYNC;
124 	hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, irq_mask);
125 
126 	free_irq(hdlcd->irq, drm);
127 }
128 
129 static int hdlcd_load(struct drm_device *drm, unsigned long flags)
130 {
131 	struct hdlcd_drm_private *hdlcd = drm->dev_private;
132 	struct platform_device *pdev = to_platform_device(drm->dev);
133 	struct resource *res;
134 	u32 version;
135 	int ret;
136 
137 	hdlcd->clk = devm_clk_get(drm->dev, "pxlclk");
138 	if (IS_ERR(hdlcd->clk))
139 		return PTR_ERR(hdlcd->clk);
140 
141 #ifdef CONFIG_DEBUG_FS
142 	atomic_set(&hdlcd->buffer_underrun_count, 0);
143 	atomic_set(&hdlcd->bus_error_count, 0);
144 	atomic_set(&hdlcd->vsync_count, 0);
145 	atomic_set(&hdlcd->dma_end_count, 0);
146 #endif
147 
148 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
149 	hdlcd->mmio = devm_ioremap_resource(drm->dev, res);
150 	if (IS_ERR(hdlcd->mmio)) {
151 		DRM_ERROR("failed to map control registers area\n");
152 		ret = PTR_ERR(hdlcd->mmio);
153 		hdlcd->mmio = NULL;
154 		return ret;
155 	}
156 
157 	version = hdlcd_read(hdlcd, HDLCD_REG_VERSION);
158 	if ((version & HDLCD_PRODUCT_MASK) != HDLCD_PRODUCT_ID) {
159 		DRM_ERROR("unknown product id: 0x%x\n", version);
160 		return -EINVAL;
161 	}
162 	DRM_INFO("found ARM HDLCD version r%dp%d\n",
163 		(version & HDLCD_VERSION_MAJOR_MASK) >> 8,
164 		version & HDLCD_VERSION_MINOR_MASK);
165 
166 	/* Get the optional framebuffer memory resource */
167 	ret = of_reserved_mem_device_init(drm->dev);
168 	if (ret && ret != -ENODEV)
169 		return ret;
170 
171 	ret = dma_set_mask_and_coherent(drm->dev, DMA_BIT_MASK(32));
172 	if (ret)
173 		goto setup_fail;
174 
175 	ret = hdlcd_setup_crtc(drm);
176 	if (ret < 0) {
177 		DRM_ERROR("failed to create crtc\n");
178 		goto setup_fail;
179 	}
180 
181 	ret = platform_get_irq(pdev, 0);
182 	if (ret < 0)
183 		goto irq_fail;
184 	hdlcd->irq = ret;
185 
186 	ret = hdlcd_irq_install(drm, hdlcd->irq);
187 	if (ret < 0) {
188 		DRM_ERROR("failed to install IRQ handler\n");
189 		goto irq_fail;
190 	}
191 
192 	return 0;
193 
194 irq_fail:
195 	drm_crtc_cleanup(&hdlcd->crtc);
196 setup_fail:
197 	of_reserved_mem_device_release(drm->dev);
198 
199 	return ret;
200 }
201 
202 static const struct drm_mode_config_funcs hdlcd_mode_config_funcs = {
203 	.fb_create = drm_gem_fb_create,
204 	.atomic_check = drm_atomic_helper_check,
205 	.atomic_commit = drm_atomic_helper_commit,
206 };
207 
208 static void hdlcd_setup_mode_config(struct drm_device *drm)
209 {
210 	drm_mode_config_init(drm);
211 	drm->mode_config.min_width = 0;
212 	drm->mode_config.min_height = 0;
213 	drm->mode_config.max_width = HDLCD_MAX_XRES;
214 	drm->mode_config.max_height = HDLCD_MAX_YRES;
215 	drm->mode_config.funcs = &hdlcd_mode_config_funcs;
216 }
217 
218 #ifdef CONFIG_DEBUG_FS
219 static int hdlcd_show_underrun_count(struct seq_file *m, void *arg)
220 {
221 	struct drm_info_node *node = (struct drm_info_node *)m->private;
222 	struct drm_device *drm = node->minor->dev;
223 	struct hdlcd_drm_private *hdlcd = drm->dev_private;
224 
225 	seq_printf(m, "underrun : %d\n", atomic_read(&hdlcd->buffer_underrun_count));
226 	seq_printf(m, "dma_end  : %d\n", atomic_read(&hdlcd->dma_end_count));
227 	seq_printf(m, "bus_error: %d\n", atomic_read(&hdlcd->bus_error_count));
228 	seq_printf(m, "vsync    : %d\n", atomic_read(&hdlcd->vsync_count));
229 	return 0;
230 }
231 
232 static int hdlcd_show_pxlclock(struct seq_file *m, void *arg)
233 {
234 	struct drm_info_node *node = (struct drm_info_node *)m->private;
235 	struct drm_device *drm = node->minor->dev;
236 	struct hdlcd_drm_private *hdlcd = drm->dev_private;
237 	unsigned long clkrate = clk_get_rate(hdlcd->clk);
238 	unsigned long mode_clock = hdlcd->crtc.mode.crtc_clock * 1000;
239 
240 	seq_printf(m, "hw  : %lu\n", clkrate);
241 	seq_printf(m, "mode: %lu\n", mode_clock);
242 	return 0;
243 }
244 
245 static struct drm_info_list hdlcd_debugfs_list[] = {
246 	{ "interrupt_count", hdlcd_show_underrun_count, 0 },
247 	{ "clocks", hdlcd_show_pxlclock, 0 },
248 };
249 
250 static void hdlcd_debugfs_init(struct drm_minor *minor)
251 {
252 	drm_debugfs_create_files(hdlcd_debugfs_list,
253 				 ARRAY_SIZE(hdlcd_debugfs_list),
254 				 minor->debugfs_root, minor);
255 }
256 #endif
257 
258 DEFINE_DRM_GEM_CMA_FOPS(fops);
259 
260 static const struct drm_driver hdlcd_driver = {
261 	.driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
262 	DRM_GEM_CMA_DRIVER_OPS,
263 #ifdef CONFIG_DEBUG_FS
264 	.debugfs_init = hdlcd_debugfs_init,
265 #endif
266 	.fops = &fops,
267 	.name = "hdlcd",
268 	.desc = "ARM HDLCD Controller DRM",
269 	.date = "20151021",
270 	.major = 1,
271 	.minor = 0,
272 };
273 
274 static int hdlcd_drm_bind(struct device *dev)
275 {
276 	struct drm_device *drm;
277 	struct hdlcd_drm_private *hdlcd;
278 	int ret;
279 
280 	hdlcd = devm_kzalloc(dev, sizeof(*hdlcd), GFP_KERNEL);
281 	if (!hdlcd)
282 		return -ENOMEM;
283 
284 	drm = drm_dev_alloc(&hdlcd_driver, dev);
285 	if (IS_ERR(drm))
286 		return PTR_ERR(drm);
287 
288 	drm->dev_private = hdlcd;
289 	dev_set_drvdata(dev, drm);
290 
291 	hdlcd_setup_mode_config(drm);
292 	ret = hdlcd_load(drm, 0);
293 	if (ret)
294 		goto err_free;
295 
296 	/* Set the CRTC's port so that the encoder component can find it */
297 	hdlcd->crtc.port = of_graph_get_port_by_id(dev->of_node, 0);
298 
299 	ret = component_bind_all(dev, drm);
300 	if (ret) {
301 		DRM_ERROR("Failed to bind all components\n");
302 		goto err_unload;
303 	}
304 
305 	ret = pm_runtime_set_active(dev);
306 	if (ret)
307 		goto err_pm_active;
308 
309 	pm_runtime_enable(dev);
310 
311 	ret = drm_vblank_init(drm, drm->mode_config.num_crtc);
312 	if (ret < 0) {
313 		DRM_ERROR("failed to initialise vblank\n");
314 		goto err_vblank;
315 	}
316 
317 	drm_mode_config_reset(drm);
318 	drm_kms_helper_poll_init(drm);
319 
320 	ret = drm_dev_register(drm, 0);
321 	if (ret)
322 		goto err_register;
323 
324 	drm_fbdev_generic_setup(drm, 32);
325 
326 	return 0;
327 
328 err_register:
329 	drm_kms_helper_poll_fini(drm);
330 err_vblank:
331 	pm_runtime_disable(drm->dev);
332 err_pm_active:
333 	drm_atomic_helper_shutdown(drm);
334 	component_unbind_all(dev, drm);
335 err_unload:
336 	of_node_put(hdlcd->crtc.port);
337 	hdlcd->crtc.port = NULL;
338 	hdlcd_irq_uninstall(drm);
339 	of_reserved_mem_device_release(drm->dev);
340 err_free:
341 	drm_mode_config_cleanup(drm);
342 	dev_set_drvdata(dev, NULL);
343 	drm_dev_put(drm);
344 
345 	return ret;
346 }
347 
348 static void hdlcd_drm_unbind(struct device *dev)
349 {
350 	struct drm_device *drm = dev_get_drvdata(dev);
351 	struct hdlcd_drm_private *hdlcd = drm->dev_private;
352 
353 	drm_dev_unregister(drm);
354 	drm_kms_helper_poll_fini(drm);
355 	component_unbind_all(dev, drm);
356 	of_node_put(hdlcd->crtc.port);
357 	hdlcd->crtc.port = NULL;
358 	pm_runtime_get_sync(dev);
359 	drm_atomic_helper_shutdown(drm);
360 	hdlcd_irq_uninstall(drm);
361 	pm_runtime_put(dev);
362 	if (pm_runtime_enabled(dev))
363 		pm_runtime_disable(dev);
364 	of_reserved_mem_device_release(dev);
365 	drm_mode_config_cleanup(drm);
366 	drm->dev_private = NULL;
367 	dev_set_drvdata(dev, NULL);
368 	drm_dev_put(drm);
369 }
370 
371 static const struct component_master_ops hdlcd_master_ops = {
372 	.bind		= hdlcd_drm_bind,
373 	.unbind		= hdlcd_drm_unbind,
374 };
375 
376 static int compare_dev(struct device *dev, void *data)
377 {
378 	return dev->of_node == data;
379 }
380 
381 static int hdlcd_probe(struct platform_device *pdev)
382 {
383 	struct device_node *port;
384 	struct component_match *match = NULL;
385 
386 	/* there is only one output port inside each device, find it */
387 	port = of_graph_get_remote_node(pdev->dev.of_node, 0, 0);
388 	if (!port)
389 		return -ENODEV;
390 
391 	drm_of_component_match_add(&pdev->dev, &match, compare_dev, port);
392 	of_node_put(port);
393 
394 	return component_master_add_with_match(&pdev->dev, &hdlcd_master_ops,
395 					       match);
396 }
397 
398 static int hdlcd_remove(struct platform_device *pdev)
399 {
400 	component_master_del(&pdev->dev, &hdlcd_master_ops);
401 	return 0;
402 }
403 
404 static const struct of_device_id  hdlcd_of_match[] = {
405 	{ .compatible	= "arm,hdlcd" },
406 	{},
407 };
408 MODULE_DEVICE_TABLE(of, hdlcd_of_match);
409 
410 static int __maybe_unused hdlcd_pm_suspend(struct device *dev)
411 {
412 	struct drm_device *drm = dev_get_drvdata(dev);
413 
414 	return drm_mode_config_helper_suspend(drm);
415 }
416 
417 static int __maybe_unused hdlcd_pm_resume(struct device *dev)
418 {
419 	struct drm_device *drm = dev_get_drvdata(dev);
420 
421 	drm_mode_config_helper_resume(drm);
422 
423 	return 0;
424 }
425 
426 static SIMPLE_DEV_PM_OPS(hdlcd_pm_ops, hdlcd_pm_suspend, hdlcd_pm_resume);
427 
428 static struct platform_driver hdlcd_platform_driver = {
429 	.probe		= hdlcd_probe,
430 	.remove		= hdlcd_remove,
431 	.driver	= {
432 		.name = "hdlcd",
433 		.pm = &hdlcd_pm_ops,
434 		.of_match_table	= hdlcd_of_match,
435 	},
436 };
437 
438 drm_module_platform_driver(hdlcd_platform_driver);
439 
440 MODULE_AUTHOR("Liviu Dudau");
441 MODULE_DESCRIPTION("ARM HDLCD DRM driver");
442 MODULE_LICENSE("GPL v2");
443