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/aperture.h>
13 #include <linux/module.h>
14 #include <linux/spinlock.h>
15 #include <linux/clk.h>
16 #include <linux/component.h>
17 #include <linux/console.h>
18 #include <linux/dma-mapping.h>
19 #include <linux/list.h>
20 #include <linux/of_graph.h>
21 #include <linux/of_reserved_mem.h>
22 #include <linux/platform_device.h>
23 #include <linux/pm_runtime.h>
24
25 #include <drm/clients/drm_client_setup.h>
26 #include <drm/drm_atomic_helper.h>
27 #include <drm/drm_crtc.h>
28 #include <drm/drm_debugfs.h>
29 #include <drm/drm_drv.h>
30 #include <drm/drm_fbdev_dma.h>
31 #include <drm/drm_gem_dma_helper.h>
32 #include <drm/drm_gem_framebuffer_helper.h>
33 #include <drm/drm_modeset_helper.h>
34 #include <drm/drm_module.h>
35 #include <drm/drm_of.h>
36 #include <drm/drm_probe_helper.h>
37 #include <drm/drm_vblank.h>
38
39 #include "hdlcd_drv.h"
40 #include "hdlcd_regs.h"
41
hdlcd_irq(int irq,void * arg)42 static irqreturn_t hdlcd_irq(int irq, void *arg)
43 {
44 struct hdlcd_drm_private *hdlcd = arg;
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
hdlcd_irq_install(struct hdlcd_drm_private * hdlcd)72 static int hdlcd_irq_install(struct hdlcd_drm_private *hdlcd)
73 {
74 int ret;
75
76 /* Ensure interrupts are disabled */
77 hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, 0);
78 hdlcd_write(hdlcd, HDLCD_REG_INT_CLEAR, ~0);
79
80 ret = request_irq(hdlcd->irq, hdlcd_irq, 0, "hdlcd", hdlcd);
81 if (ret)
82 return ret;
83
84 #ifdef CONFIG_DEBUG_FS
85 /* enable debug interrupts */
86 hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, HDLCD_DEBUG_INT_MASK);
87 #endif
88
89 return 0;
90 }
91
hdlcd_irq_uninstall(struct hdlcd_drm_private * hdlcd)92 static void hdlcd_irq_uninstall(struct hdlcd_drm_private *hdlcd)
93 {
94 /* disable all the interrupts that we might have enabled */
95 hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, 0);
96
97 free_irq(hdlcd->irq, hdlcd);
98 }
99
hdlcd_load(struct drm_device * drm,unsigned long flags)100 static int hdlcd_load(struct drm_device *drm, unsigned long flags)
101 {
102 struct hdlcd_drm_private *hdlcd = drm_to_hdlcd_priv(drm);
103 struct platform_device *pdev = to_platform_device(drm->dev);
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 hdlcd->mmio = devm_platform_ioremap_resource(pdev, 0);
119 if (IS_ERR(hdlcd->mmio)) {
120 DRM_ERROR("failed to map control registers area\n");
121 ret = PTR_ERR(hdlcd->mmio);
122 hdlcd->mmio = NULL;
123 return ret;
124 }
125
126 version = hdlcd_read(hdlcd, HDLCD_REG_VERSION);
127 if ((version & HDLCD_PRODUCT_MASK) != HDLCD_PRODUCT_ID) {
128 DRM_ERROR("unknown product id: 0x%x\n", version);
129 return -EINVAL;
130 }
131 DRM_INFO("found ARM HDLCD version r%dp%d\n",
132 (version & HDLCD_VERSION_MAJOR_MASK) >> 8,
133 version & HDLCD_VERSION_MINOR_MASK);
134
135 /* Get the optional framebuffer memory resource */
136 ret = of_reserved_mem_device_init(drm->dev);
137 if (ret && ret != -ENODEV)
138 return ret;
139
140 ret = dma_set_mask_and_coherent(drm->dev, DMA_BIT_MASK(32));
141 if (ret)
142 goto setup_fail;
143
144 ret = hdlcd_setup_crtc(drm);
145 if (ret < 0) {
146 DRM_ERROR("failed to create crtc\n");
147 goto setup_fail;
148 }
149
150 ret = platform_get_irq(pdev, 0);
151 if (ret < 0)
152 goto irq_fail;
153 hdlcd->irq = ret;
154
155 ret = hdlcd_irq_install(hdlcd);
156 if (ret < 0) {
157 DRM_ERROR("failed to install IRQ handler\n");
158 goto irq_fail;
159 }
160
161 return 0;
162
163 irq_fail:
164 drm_crtc_cleanup(&hdlcd->crtc);
165 setup_fail:
166 of_reserved_mem_device_release(drm->dev);
167
168 return ret;
169 }
170
171 static const struct drm_mode_config_funcs hdlcd_mode_config_funcs = {
172 .fb_create = drm_gem_fb_create,
173 .atomic_check = drm_atomic_helper_check,
174 .atomic_commit = drm_atomic_helper_commit,
175 };
176
hdlcd_setup_mode_config(struct drm_device * drm)177 static int hdlcd_setup_mode_config(struct drm_device *drm)
178 {
179 int ret;
180
181 ret = drmm_mode_config_init(drm);
182 if (ret)
183 return ret;
184
185 drm->mode_config.min_width = 0;
186 drm->mode_config.min_height = 0;
187 drm->mode_config.max_width = HDLCD_MAX_XRES;
188 drm->mode_config.max_height = HDLCD_MAX_YRES;
189 drm->mode_config.funcs = &hdlcd_mode_config_funcs;
190
191 return 0;
192 }
193
194 #ifdef CONFIG_DEBUG_FS
hdlcd_show_underrun_count(struct seq_file * m,void * arg)195 static int hdlcd_show_underrun_count(struct seq_file *m, void *arg)
196 {
197 struct drm_debugfs_entry *entry = m->private;
198 struct drm_device *drm = entry->dev;
199 struct hdlcd_drm_private *hdlcd = drm_to_hdlcd_priv(drm);
200
201 seq_printf(m, "underrun : %d\n", atomic_read(&hdlcd->buffer_underrun_count));
202 seq_printf(m, "dma_end : %d\n", atomic_read(&hdlcd->dma_end_count));
203 seq_printf(m, "bus_error: %d\n", atomic_read(&hdlcd->bus_error_count));
204 seq_printf(m, "vsync : %d\n", atomic_read(&hdlcd->vsync_count));
205 return 0;
206 }
207
hdlcd_show_pxlclock(struct seq_file * m,void * arg)208 static int hdlcd_show_pxlclock(struct seq_file *m, void *arg)
209 {
210 struct drm_debugfs_entry *entry = m->private;
211 struct drm_device *drm = entry->dev;
212 struct hdlcd_drm_private *hdlcd = drm_to_hdlcd_priv(drm);
213 unsigned long clkrate = clk_get_rate(hdlcd->clk);
214 unsigned long mode_clock = hdlcd->crtc.mode.crtc_clock * 1000;
215
216 seq_printf(m, "hw : %lu\n", clkrate);
217 seq_printf(m, "mode: %lu\n", mode_clock);
218 return 0;
219 }
220
221 static struct drm_debugfs_info hdlcd_debugfs_list[] = {
222 { "interrupt_count", hdlcd_show_underrun_count, 0 },
223 { "clocks", hdlcd_show_pxlclock, 0 },
224 };
225 #endif
226
227 DEFINE_DRM_GEM_DMA_FOPS(fops);
228
229 static const struct drm_driver hdlcd_driver = {
230 .driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
231 DRM_GEM_DMA_DRIVER_OPS,
232 DRM_FBDEV_DMA_DRIVER_OPS,
233 .fops = &fops,
234 .name = "hdlcd",
235 .desc = "ARM HDLCD Controller DRM",
236 .major = 1,
237 .minor = 0,
238 };
239
hdlcd_drm_bind(struct device * dev)240 static int hdlcd_drm_bind(struct device *dev)
241 {
242 struct drm_device *drm;
243 struct hdlcd_drm_private *hdlcd;
244 int ret;
245
246 hdlcd = devm_drm_dev_alloc(dev, &hdlcd_driver, typeof(*hdlcd), base);
247 if (IS_ERR(hdlcd))
248 return PTR_ERR(hdlcd);
249
250 drm = &hdlcd->base;
251
252 dev_set_drvdata(dev, drm);
253
254 ret = hdlcd_setup_mode_config(drm);
255 if (ret)
256 goto err_free;
257
258 ret = hdlcd_load(drm, 0);
259 if (ret)
260 goto err_free;
261
262 /* Set the CRTC's port so that the encoder component can find it */
263 hdlcd->crtc.port = of_graph_get_port_by_id(dev->of_node, 0);
264
265 ret = component_bind_all(dev, drm);
266 if (ret) {
267 DRM_ERROR("Failed to bind all components\n");
268 goto err_unload;
269 }
270
271 ret = pm_runtime_set_active(dev);
272 if (ret)
273 goto err_pm_active;
274
275 pm_runtime_enable(dev);
276
277 ret = drm_vblank_init(drm, drm->mode_config.num_crtc);
278 if (ret < 0) {
279 DRM_ERROR("failed to initialise vblank\n");
280 goto err_vblank;
281 }
282
283 /*
284 * If EFI left us running, take over from simple framebuffer
285 * drivers. Read HDLCD_REG_COMMAND to see if we are enabled.
286 */
287 if (hdlcd_read(hdlcd, HDLCD_REG_COMMAND)) {
288 hdlcd_write(hdlcd, HDLCD_REG_COMMAND, 0);
289 aperture_remove_all_conflicting_devices(hdlcd_driver.name);
290 }
291
292 drm_mode_config_reset(drm);
293 drm_kms_helper_poll_init(drm);
294
295 #ifdef CONFIG_DEBUG_FS
296 drm_debugfs_add_files(drm, hdlcd_debugfs_list, ARRAY_SIZE(hdlcd_debugfs_list));
297 #endif
298
299 ret = drm_dev_register(drm, 0);
300 if (ret)
301 goto err_register;
302
303 drm_client_setup(drm, NULL);
304
305 return 0;
306
307 err_register:
308 drm_kms_helper_poll_fini(drm);
309 err_vblank:
310 pm_runtime_disable(drm->dev);
311 err_pm_active:
312 drm_atomic_helper_shutdown(drm);
313 component_unbind_all(dev, drm);
314 err_unload:
315 of_node_put(hdlcd->crtc.port);
316 hdlcd->crtc.port = NULL;
317 hdlcd_irq_uninstall(hdlcd);
318 of_reserved_mem_device_release(drm->dev);
319 err_free:
320 dev_set_drvdata(dev, NULL);
321 return ret;
322 }
323
hdlcd_drm_unbind(struct device * dev)324 static void hdlcd_drm_unbind(struct device *dev)
325 {
326 struct drm_device *drm = dev_get_drvdata(dev);
327 struct hdlcd_drm_private *hdlcd = drm_to_hdlcd_priv(drm);
328
329 drm_dev_unregister(drm);
330 drm_kms_helper_poll_fini(drm);
331 component_unbind_all(dev, drm);
332 of_node_put(hdlcd->crtc.port);
333 hdlcd->crtc.port = NULL;
334 pm_runtime_get_sync(dev);
335 drm_atomic_helper_shutdown(drm);
336 hdlcd_irq_uninstall(hdlcd);
337 pm_runtime_put(dev);
338 if (pm_runtime_enabled(dev))
339 pm_runtime_disable(dev);
340 of_reserved_mem_device_release(dev);
341 dev_set_drvdata(dev, NULL);
342 }
343
344 static const struct component_master_ops hdlcd_master_ops = {
345 .bind = hdlcd_drm_bind,
346 .unbind = hdlcd_drm_unbind,
347 };
348
compare_dev(struct device * dev,void * data)349 static int compare_dev(struct device *dev, void *data)
350 {
351 return dev->of_node == data;
352 }
353
hdlcd_probe(struct platform_device * pdev)354 static int hdlcd_probe(struct platform_device *pdev)
355 {
356 struct device_node *port;
357 struct component_match *match = NULL;
358
359 /* there is only one output port inside each device, find it */
360 port = of_graph_get_remote_node(pdev->dev.of_node, 0, 0);
361 if (!port)
362 return -ENODEV;
363
364 drm_of_component_match_add(&pdev->dev, &match, compare_dev, port);
365 of_node_put(port);
366
367 return component_master_add_with_match(&pdev->dev, &hdlcd_master_ops,
368 match);
369 }
370
hdlcd_remove(struct platform_device * pdev)371 static void hdlcd_remove(struct platform_device *pdev)
372 {
373 component_master_del(&pdev->dev, &hdlcd_master_ops);
374 }
375
hdlcd_shutdown(struct platform_device * pdev)376 static void hdlcd_shutdown(struct platform_device *pdev)
377 {
378 drm_atomic_helper_shutdown(platform_get_drvdata(pdev));
379 }
380
381 static const struct of_device_id hdlcd_of_match[] = {
382 { .compatible = "arm,hdlcd" },
383 {},
384 };
385 MODULE_DEVICE_TABLE(of, hdlcd_of_match);
386
hdlcd_pm_suspend(struct device * dev)387 static int __maybe_unused hdlcd_pm_suspend(struct device *dev)
388 {
389 struct drm_device *drm = dev_get_drvdata(dev);
390
391 return drm_mode_config_helper_suspend(drm);
392 }
393
hdlcd_pm_resume(struct device * dev)394 static int __maybe_unused hdlcd_pm_resume(struct device *dev)
395 {
396 struct drm_device *drm = dev_get_drvdata(dev);
397
398 drm_mode_config_helper_resume(drm);
399
400 return 0;
401 }
402
403 static SIMPLE_DEV_PM_OPS(hdlcd_pm_ops, hdlcd_pm_suspend, hdlcd_pm_resume);
404
405 static struct platform_driver hdlcd_platform_driver = {
406 .probe = hdlcd_probe,
407 .remove = hdlcd_remove,
408 .shutdown = hdlcd_shutdown,
409 .driver = {
410 .name = "hdlcd",
411 .pm = &hdlcd_pm_ops,
412 .of_match_table = hdlcd_of_match,
413 },
414 };
415
416 drm_module_platform_driver(hdlcd_platform_driver);
417
418 MODULE_AUTHOR("Liviu Dudau");
419 MODULE_DESCRIPTION("ARM HDLCD DRM driver");
420 MODULE_LICENSE("GPL v2");
421