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
hdlcd_irq(int irq,void * arg)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
hdlcd_irq_preinstall(struct drm_device * drm)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
hdlcd_irq_postinstall(struct drm_device * drm)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
hdlcd_irq_install(struct drm_device * drm,int irq)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
hdlcd_irq_uninstall(struct drm_device * drm)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
hdlcd_load(struct drm_device * drm,unsigned long flags)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
hdlcd_setup_mode_config(struct drm_device * drm)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
hdlcd_show_underrun_count(struct seq_file * m,void * arg)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
hdlcd_show_pxlclock(struct seq_file * m,void * arg)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
hdlcd_debugfs_init(struct drm_minor * minor)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
hdlcd_drm_bind(struct device * dev)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
hdlcd_drm_unbind(struct device * dev)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
compare_dev(struct device * dev,void * data)375 static int compare_dev(struct device *dev, void *data)
376 {
377 return dev->of_node == data;
378 }
379
hdlcd_probe(struct platform_device * pdev)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
hdlcd_remove(struct platform_device * pdev)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
hdlcd_pm_suspend(struct device * dev)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
hdlcd_pm_resume(struct device * dev)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