xref: /openbmc/linux/drivers/gpu/drm/arm/hdlcd_drv.c (revision 2cf1c348)
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_of.h>
34 #include <drm/drm_probe_helper.h>
35 #include <drm/drm_vblank.h>
36 
37 #include "hdlcd_drv.h"
38 #include "hdlcd_regs.h"
39 
40 static irqreturn_t hdlcd_irq(int irq, void *arg)
41 {
42 	struct drm_device *drm = arg;
43 	struct hdlcd_drm_private *hdlcd = drm->dev_private;
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 void hdlcd_irq_preinstall(struct drm_device *drm)
72 {
73 	struct hdlcd_drm_private *hdlcd = drm->dev_private;
74 	/* Ensure interrupts are disabled */
75 	hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, 0);
76 	hdlcd_write(hdlcd, HDLCD_REG_INT_CLEAR, ~0);
77 }
78 
79 static void hdlcd_irq_postinstall(struct drm_device *drm)
80 {
81 #ifdef CONFIG_DEBUG_FS
82 	struct hdlcd_drm_private *hdlcd = drm->dev_private;
83 	unsigned long irq_mask = hdlcd_read(hdlcd, HDLCD_REG_INT_MASK);
84 
85 	/* enable debug interrupts */
86 	irq_mask |= HDLCD_DEBUG_INT_MASK;
87 
88 	hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, irq_mask);
89 #endif
90 }
91 
92 static int hdlcd_irq_install(struct drm_device *drm, int irq)
93 {
94 	int ret;
95 
96 	if (irq == IRQ_NOTCONNECTED)
97 		return -ENOTCONN;
98 
99 	hdlcd_irq_preinstall(drm);
100 
101 	ret = request_irq(irq, hdlcd_irq, 0, drm->driver->name, drm);
102 	if (ret)
103 		return ret;
104 
105 	hdlcd_irq_postinstall(drm);
106 
107 	return 0;
108 }
109 
110 static void hdlcd_irq_uninstall(struct drm_device *drm)
111 {
112 	struct hdlcd_drm_private *hdlcd = drm->dev_private;
113 	/* disable all the interrupts that we might have enabled */
114 	unsigned long irq_mask = hdlcd_read(hdlcd, HDLCD_REG_INT_MASK);
115 
116 #ifdef CONFIG_DEBUG_FS
117 	/* disable debug interrupts */
118 	irq_mask &= ~HDLCD_DEBUG_INT_MASK;
119 #endif
120 
121 	/* disable vsync interrupts */
122 	irq_mask &= ~HDLCD_INTERRUPT_VSYNC;
123 	hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, irq_mask);
124 
125 	free_irq(hdlcd->irq, drm);
126 }
127 
128 static int hdlcd_load(struct drm_device *drm, unsigned long flags)
129 {
130 	struct hdlcd_drm_private *hdlcd = drm->dev_private;
131 	struct platform_device *pdev = to_platform_device(drm->dev);
132 	struct resource *res;
133 	u32 version;
134 	int ret;
135 
136 	hdlcd->clk = devm_clk_get(drm->dev, "pxlclk");
137 	if (IS_ERR(hdlcd->clk))
138 		return PTR_ERR(hdlcd->clk);
139 
140 #ifdef CONFIG_DEBUG_FS
141 	atomic_set(&hdlcd->buffer_underrun_count, 0);
142 	atomic_set(&hdlcd->bus_error_count, 0);
143 	atomic_set(&hdlcd->vsync_count, 0);
144 	atomic_set(&hdlcd->dma_end_count, 0);
145 #endif
146 
147 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
148 	hdlcd->mmio = devm_ioremap_resource(drm->dev, res);
149 	if (IS_ERR(hdlcd->mmio)) {
150 		DRM_ERROR("failed to map control registers area\n");
151 		ret = PTR_ERR(hdlcd->mmio);
152 		hdlcd->mmio = NULL;
153 		return ret;
154 	}
155 
156 	version = hdlcd_read(hdlcd, HDLCD_REG_VERSION);
157 	if ((version & HDLCD_PRODUCT_MASK) != HDLCD_PRODUCT_ID) {
158 		DRM_ERROR("unknown product id: 0x%x\n", version);
159 		return -EINVAL;
160 	}
161 	DRM_INFO("found ARM HDLCD version r%dp%d\n",
162 		(version & HDLCD_VERSION_MAJOR_MASK) >> 8,
163 		version & HDLCD_VERSION_MINOR_MASK);
164 
165 	/* Get the optional framebuffer memory resource */
166 	ret = of_reserved_mem_device_init(drm->dev);
167 	if (ret && ret != -ENODEV)
168 		return ret;
169 
170 	ret = dma_set_mask_and_coherent(drm->dev, DMA_BIT_MASK(32));
171 	if (ret)
172 		goto setup_fail;
173 
174 	ret = hdlcd_setup_crtc(drm);
175 	if (ret < 0) {
176 		DRM_ERROR("failed to create crtc\n");
177 		goto setup_fail;
178 	}
179 
180 	ret = platform_get_irq(pdev, 0);
181 	if (ret < 0)
182 		goto irq_fail;
183 	hdlcd->irq = ret;
184 
185 	ret = hdlcd_irq_install(drm, hdlcd->irq);
186 	if (ret < 0) {
187 		DRM_ERROR("failed to install IRQ handler\n");
188 		goto irq_fail;
189 	}
190 
191 	return 0;
192 
193 irq_fail:
194 	drm_crtc_cleanup(&hdlcd->crtc);
195 setup_fail:
196 	of_reserved_mem_device_release(drm->dev);
197 
198 	return ret;
199 }
200 
201 static const struct drm_mode_config_funcs hdlcd_mode_config_funcs = {
202 	.fb_create = drm_gem_fb_create,
203 	.atomic_check = drm_atomic_helper_check,
204 	.atomic_commit = drm_atomic_helper_commit,
205 };
206 
207 static void hdlcd_setup_mode_config(struct drm_device *drm)
208 {
209 	drm_mode_config_init(drm);
210 	drm->mode_config.min_width = 0;
211 	drm->mode_config.min_height = 0;
212 	drm->mode_config.max_width = HDLCD_MAX_XRES;
213 	drm->mode_config.max_height = HDLCD_MAX_YRES;
214 	drm->mode_config.funcs = &hdlcd_mode_config_funcs;
215 }
216 
217 #ifdef CONFIG_DEBUG_FS
218 static int hdlcd_show_underrun_count(struct seq_file *m, void *arg)
219 {
220 	struct drm_info_node *node = (struct drm_info_node *)m->private;
221 	struct drm_device *drm = node->minor->dev;
222 	struct hdlcd_drm_private *hdlcd = drm->dev_private;
223 
224 	seq_printf(m, "underrun : %d\n", atomic_read(&hdlcd->buffer_underrun_count));
225 	seq_printf(m, "dma_end  : %d\n", atomic_read(&hdlcd->dma_end_count));
226 	seq_printf(m, "bus_error: %d\n", atomic_read(&hdlcd->bus_error_count));
227 	seq_printf(m, "vsync    : %d\n", atomic_read(&hdlcd->vsync_count));
228 	return 0;
229 }
230 
231 static int hdlcd_show_pxlclock(struct seq_file *m, void *arg)
232 {
233 	struct drm_info_node *node = (struct drm_info_node *)m->private;
234 	struct drm_device *drm = node->minor->dev;
235 	struct hdlcd_drm_private *hdlcd = drm->dev_private;
236 	unsigned long clkrate = clk_get_rate(hdlcd->clk);
237 	unsigned long mode_clock = hdlcd->crtc.mode.crtc_clock * 1000;
238 
239 	seq_printf(m, "hw  : %lu\n", clkrate);
240 	seq_printf(m, "mode: %lu\n", mode_clock);
241 	return 0;
242 }
243 
244 static struct drm_info_list hdlcd_debugfs_list[] = {
245 	{ "interrupt_count", hdlcd_show_underrun_count, 0 },
246 	{ "clocks", hdlcd_show_pxlclock, 0 },
247 };
248 
249 static void hdlcd_debugfs_init(struct drm_minor *minor)
250 {
251 	drm_debugfs_create_files(hdlcd_debugfs_list,
252 				 ARRAY_SIZE(hdlcd_debugfs_list),
253 				 minor->debugfs_root, minor);
254 }
255 #endif
256 
257 DEFINE_DRM_GEM_CMA_FOPS(fops);
258 
259 static const struct drm_driver hdlcd_driver = {
260 	.driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
261 	DRM_GEM_CMA_DRIVER_OPS,
262 #ifdef CONFIG_DEBUG_FS
263 	.debugfs_init = hdlcd_debugfs_init,
264 #endif
265 	.fops = &fops,
266 	.name = "hdlcd",
267 	.desc = "ARM HDLCD Controller DRM",
268 	.date = "20151021",
269 	.major = 1,
270 	.minor = 0,
271 };
272 
273 static int hdlcd_drm_bind(struct device *dev)
274 {
275 	struct drm_device *drm;
276 	struct hdlcd_drm_private *hdlcd;
277 	int ret;
278 
279 	hdlcd = devm_kzalloc(dev, sizeof(*hdlcd), GFP_KERNEL);
280 	if (!hdlcd)
281 		return -ENOMEM;
282 
283 	drm = drm_dev_alloc(&hdlcd_driver, dev);
284 	if (IS_ERR(drm))
285 		return PTR_ERR(drm);
286 
287 	drm->dev_private = hdlcd;
288 	dev_set_drvdata(dev, drm);
289 
290 	hdlcd_setup_mode_config(drm);
291 	ret = hdlcd_load(drm, 0);
292 	if (ret)
293 		goto err_free;
294 
295 	/* Set the CRTC's port so that the encoder component can find it */
296 	hdlcd->crtc.port = of_graph_get_port_by_id(dev->of_node, 0);
297 
298 	ret = component_bind_all(dev, drm);
299 	if (ret) {
300 		DRM_ERROR("Failed to bind all components\n");
301 		goto err_unload;
302 	}
303 
304 	ret = pm_runtime_set_active(dev);
305 	if (ret)
306 		goto err_pm_active;
307 
308 	pm_runtime_enable(dev);
309 
310 	ret = drm_vblank_init(drm, drm->mode_config.num_crtc);
311 	if (ret < 0) {
312 		DRM_ERROR("failed to initialise vblank\n");
313 		goto err_vblank;
314 	}
315 
316 	drm_mode_config_reset(drm);
317 	drm_kms_helper_poll_init(drm);
318 
319 	ret = drm_dev_register(drm, 0);
320 	if (ret)
321 		goto err_register;
322 
323 	drm_fbdev_generic_setup(drm, 32);
324 
325 	return 0;
326 
327 err_register:
328 	drm_kms_helper_poll_fini(drm);
329 err_vblank:
330 	pm_runtime_disable(drm->dev);
331 err_pm_active:
332 	drm_atomic_helper_shutdown(drm);
333 	component_unbind_all(dev, drm);
334 err_unload:
335 	of_node_put(hdlcd->crtc.port);
336 	hdlcd->crtc.port = NULL;
337 	hdlcd_irq_uninstall(drm);
338 	of_reserved_mem_device_release(drm->dev);
339 err_free:
340 	drm_mode_config_cleanup(drm);
341 	dev_set_drvdata(dev, NULL);
342 	drm_dev_put(drm);
343 
344 	return ret;
345 }
346 
347 static void hdlcd_drm_unbind(struct device *dev)
348 {
349 	struct drm_device *drm = dev_get_drvdata(dev);
350 	struct hdlcd_drm_private *hdlcd = drm->dev_private;
351 
352 	drm_dev_unregister(drm);
353 	drm_kms_helper_poll_fini(drm);
354 	component_unbind_all(dev, drm);
355 	of_node_put(hdlcd->crtc.port);
356 	hdlcd->crtc.port = NULL;
357 	pm_runtime_get_sync(dev);
358 	drm_atomic_helper_shutdown(drm);
359 	hdlcd_irq_uninstall(drm);
360 	pm_runtime_put(dev);
361 	if (pm_runtime_enabled(dev))
362 		pm_runtime_disable(dev);
363 	of_reserved_mem_device_release(dev);
364 	drm_mode_config_cleanup(drm);
365 	drm->dev_private = NULL;
366 	dev_set_drvdata(dev, NULL);
367 	drm_dev_put(drm);
368 }
369 
370 static const struct component_master_ops hdlcd_master_ops = {
371 	.bind		= hdlcd_drm_bind,
372 	.unbind		= hdlcd_drm_unbind,
373 };
374 
375 static int compare_dev(struct device *dev, void *data)
376 {
377 	return dev->of_node == data;
378 }
379 
380 static int hdlcd_probe(struct platform_device *pdev)
381 {
382 	struct device_node *port;
383 	struct component_match *match = NULL;
384 
385 	/* there is only one output port inside each device, find it */
386 	port = of_graph_get_remote_node(pdev->dev.of_node, 0, 0);
387 	if (!port)
388 		return -ENODEV;
389 
390 	drm_of_component_match_add(&pdev->dev, &match, compare_dev, port);
391 	of_node_put(port);
392 
393 	return component_master_add_with_match(&pdev->dev, &hdlcd_master_ops,
394 					       match);
395 }
396 
397 static int hdlcd_remove(struct platform_device *pdev)
398 {
399 	component_master_del(&pdev->dev, &hdlcd_master_ops);
400 	return 0;
401 }
402 
403 static const struct of_device_id  hdlcd_of_match[] = {
404 	{ .compatible	= "arm,hdlcd" },
405 	{},
406 };
407 MODULE_DEVICE_TABLE(of, hdlcd_of_match);
408 
409 static int __maybe_unused hdlcd_pm_suspend(struct device *dev)
410 {
411 	struct drm_device *drm = dev_get_drvdata(dev);
412 
413 	return drm_mode_config_helper_suspend(drm);
414 }
415 
416 static int __maybe_unused hdlcd_pm_resume(struct device *dev)
417 {
418 	struct drm_device *drm = dev_get_drvdata(dev);
419 
420 	drm_mode_config_helper_resume(drm);
421 
422 	return 0;
423 }
424 
425 static SIMPLE_DEV_PM_OPS(hdlcd_pm_ops, hdlcd_pm_suspend, hdlcd_pm_resume);
426 
427 static struct platform_driver hdlcd_platform_driver = {
428 	.probe		= hdlcd_probe,
429 	.remove		= hdlcd_remove,
430 	.driver	= {
431 		.name = "hdlcd",
432 		.pm = &hdlcd_pm_ops,
433 		.of_match_table	= hdlcd_of_match,
434 	},
435 };
436 
437 module_platform_driver(hdlcd_platform_driver);
438 
439 MODULE_AUTHOR("Liviu Dudau");
440 MODULE_DESCRIPTION("ARM HDLCD DRM driver");
441 MODULE_LICENSE("GPL v2");
442