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