1 /*
2 * Copyright © 2016 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21 * IN THE SOFTWARE.
22 *
23 * Authors:
24 * Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
25 * Jerome Anand <jerome.anand@intel.com>
26 * based on VED patches
27 *
28 */
29
30 /**
31 * DOC: LPE Audio integration for HDMI or DP playback
32 *
33 * Motivation:
34 * Atom platforms (e.g. valleyview and cherryTrail) integrates a DMA-based
35 * interface as an alternative to the traditional HDaudio path. While this
36 * mode is unrelated to the LPE aka SST audio engine, the documentation refers
37 * to this mode as LPE so we keep this notation for the sake of consistency.
38 *
39 * The interface is handled by a separate standalone driver maintained in the
40 * ALSA subsystem for simplicity. To minimize the interaction between the two
41 * subsystems, a bridge is setup between the hdmi-lpe-audio and i915:
42 * 1. Create a platform device to share MMIO/IRQ resources
43 * 2. Make the platform device child of i915 device for runtime PM.
44 * 3. Create IRQ chip to forward the LPE audio irqs.
45 * the hdmi-lpe-audio driver probes the lpe audio device and creates a new
46 * sound card
47 *
48 * Threats:
49 * Due to the restriction in Linux platform device model, user need manually
50 * uninstall the hdmi-lpe-audio driver before uninstalling i915 module,
51 * otherwise we might run into use-after-free issues after i915 removes the
52 * platform device: even though hdmi-lpe-audio driver is released, the modules
53 * is still in "installed" status.
54 *
55 * Implementation:
56 * The MMIO/REG platform resources are created according to the registers
57 * specification.
58 * When forwarding LPE audio irqs, the flow control handler selection depends
59 * on the platform, for example on valleyview handle_simple_irq is enough.
60 *
61 */
62
63 #include <linux/acpi.h>
64 #include <linux/delay.h>
65 #include <linux/device.h>
66 #include <linux/irq.h>
67 #include <linux/pci.h>
68 #include <linux/platform_device.h>
69 #include <linux/pm_runtime.h>
70
71 #include <drm/intel_lpe_audio.h>
72
73 #include "i915_drv.h"
74 #include "i915_irq.h"
75 #include "i915_reg.h"
76 #include "intel_de.h"
77 #include "intel_lpe_audio.h"
78 #include "intel_pci_config.h"
79
80 #define HAS_LPE_AUDIO(dev_priv) ((dev_priv)->display.audio.lpe.platdev != NULL)
81
82 static struct platform_device *
lpe_audio_platdev_create(struct drm_i915_private * dev_priv)83 lpe_audio_platdev_create(struct drm_i915_private *dev_priv)
84 {
85 STUB();
86 return NULL;
87 #ifdef notyet
88 struct pci_dev *pdev = to_pci_dev(dev_priv->drm.dev);
89 struct platform_device_info pinfo = {};
90 struct resource *rsc;
91 struct platform_device *platdev;
92 struct intel_hdmi_lpe_audio_pdata *pdata;
93
94 pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
95 if (!pdata)
96 return ERR_PTR(-ENOMEM);
97
98 rsc = kcalloc(2, sizeof(*rsc), GFP_KERNEL);
99 if (!rsc) {
100 kfree(pdata);
101 return ERR_PTR(-ENOMEM);
102 }
103
104 rsc[0].start = rsc[0].end = dev_priv->display.audio.lpe.irq;
105 rsc[0].flags = IORESOURCE_IRQ;
106 rsc[0].name = "hdmi-lpe-audio-irq";
107
108 rsc[1].start = pci_resource_start(pdev, GEN4_GTTMMADR_BAR) +
109 I915_HDMI_LPE_AUDIO_BASE;
110 rsc[1].end = pci_resource_start(pdev, GEN4_GTTMMADR_BAR) +
111 I915_HDMI_LPE_AUDIO_BASE + I915_HDMI_LPE_AUDIO_SIZE - 1;
112 rsc[1].flags = IORESOURCE_MEM;
113 rsc[1].name = "hdmi-lpe-audio-mmio";
114
115 pinfo.parent = dev_priv->drm.dev;
116 pinfo.name = "hdmi-lpe-audio";
117 pinfo.id = -1;
118 pinfo.res = rsc;
119 pinfo.num_res = 2;
120 pinfo.data = pdata;
121 pinfo.size_data = sizeof(*pdata);
122 pinfo.dma_mask = DMA_BIT_MASK(32);
123
124 pdata->num_pipes = INTEL_NUM_PIPES(dev_priv);
125 pdata->num_ports = IS_CHERRYVIEW(dev_priv) ? 3 : 2; /* B,C,D or B,C */
126 pdata->port[0].pipe = -1;
127 pdata->port[1].pipe = -1;
128 pdata->port[2].pipe = -1;
129 mtx_init(&pdata->lpe_audio_slock, IPL_TTY);
130
131 platdev = platform_device_register_full(&pinfo);
132 kfree(rsc);
133 kfree(pdata);
134
135 if (IS_ERR(platdev)) {
136 drm_err(&dev_priv->drm,
137 "Failed to allocate LPE audio platform device\n");
138 return platdev;
139 }
140
141 pm_runtime_no_callbacks(&platdev->dev);
142
143 return platdev;
144 #endif
145 }
146
lpe_audio_platdev_destroy(struct drm_i915_private * dev_priv)147 static void lpe_audio_platdev_destroy(struct drm_i915_private *dev_priv)
148 {
149 /* XXX Note that platform_device_register_full() allocates a dma_mask
150 * and never frees it. We can't free it here as we cannot guarantee
151 * this is the last reference (i.e. that the dma_mask will not be
152 * used after our unregister). So ee choose to leak the sizeof(u64)
153 * allocation here - it should be fixed in the platform_device rather
154 * than us fiddle with its internals.
155 */
156
157 #ifdef __linux__
158 platform_device_unregister(dev_priv->display.audio.lpe.platdev);
159 #endif
160 }
161
162 #ifdef __linux__
lpe_audio_irq_unmask(struct irq_data * d)163 static void lpe_audio_irq_unmask(struct irq_data *d)
164 {
165 }
166
lpe_audio_irq_mask(struct irq_data * d)167 static void lpe_audio_irq_mask(struct irq_data *d)
168 {
169 }
170
171 static struct irq_chip lpe_audio_irqchip = {
172 .name = "hdmi_lpe_audio_irqchip",
173 .irq_mask = lpe_audio_irq_mask,
174 .irq_unmask = lpe_audio_irq_unmask,
175 };
176 #endif
177
lpe_audio_irq_init(struct drm_i915_private * dev_priv)178 static int lpe_audio_irq_init(struct drm_i915_private *dev_priv)
179 {
180 STUB();
181 return -ENOSYS;
182 #ifdef notyet
183 int irq = dev_priv->display.audio.lpe.irq;
184
185 drm_WARN_ON(&dev_priv->drm, !intel_irqs_enabled(dev_priv));
186 irq_set_chip_and_handler_name(irq,
187 &lpe_audio_irqchip,
188 handle_simple_irq,
189 "hdmi_lpe_audio_irq_handler");
190
191 return irq_set_chip_data(irq, dev_priv);
192 #endif
193 }
194
lpe_audio_detect(struct drm_i915_private * dev_priv)195 static bool lpe_audio_detect(struct drm_i915_private *dev_priv)
196 {
197 return false;
198 #ifdef notyet
199 int lpe_present = false;
200
201 if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
202 static const struct pci_device_id atom_hdaudio_ids[] = {
203 /* Baytrail */
204 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x0f04)},
205 /* Braswell */
206 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2284)},
207 {}
208 };
209
210 if (!pci_dev_present(atom_hdaudio_ids)) {
211 drm_info(&dev_priv->drm,
212 "HDaudio controller not detected, using LPE audio instead\n");
213 lpe_present = true;
214 }
215 }
216 return lpe_present;
217 #endif
218 }
219
lpe_audio_setup(struct drm_i915_private * dev_priv)220 static int lpe_audio_setup(struct drm_i915_private *dev_priv)
221 {
222 STUB();
223 return -ENOSYS;
224 #ifdef notyet
225 int ret;
226
227 dev_priv->display.audio.lpe.irq = irq_alloc_desc(0);
228 if (dev_priv->display.audio.lpe.irq < 0) {
229 drm_err(&dev_priv->drm, "Failed to allocate IRQ desc: %d\n",
230 dev_priv->display.audio.lpe.irq);
231 ret = dev_priv->display.audio.lpe.irq;
232 goto err;
233 }
234
235 drm_dbg(&dev_priv->drm, "irq = %d\n", dev_priv->display.audio.lpe.irq);
236
237 ret = lpe_audio_irq_init(dev_priv);
238
239 if (ret) {
240 drm_err(&dev_priv->drm,
241 "Failed to initialize irqchip for lpe audio: %d\n",
242 ret);
243 goto err_free_irq;
244 }
245
246 dev_priv->display.audio.lpe.platdev = lpe_audio_platdev_create(dev_priv);
247
248 if (IS_ERR(dev_priv->display.audio.lpe.platdev)) {
249 ret = PTR_ERR(dev_priv->display.audio.lpe.platdev);
250 drm_err(&dev_priv->drm,
251 "Failed to create lpe audio platform device: %d\n",
252 ret);
253 goto err_free_irq;
254 }
255
256 /* enable chicken bit; at least this is required for Dell Wyse 3040
257 * with DP outputs (but only sometimes by some reason!)
258 */
259 intel_de_write(dev_priv, VLV_AUD_CHICKEN_BIT_REG,
260 VLV_CHICKEN_BIT_DBG_ENABLE);
261
262 return 0;
263 err_free_irq:
264 irq_free_desc(dev_priv->display.audio.lpe.irq);
265 err:
266 dev_priv->display.audio.lpe.irq = -1;
267 dev_priv->display.audio.lpe.platdev = NULL;
268 return ret;
269 #endif
270 }
271
272 /**
273 * intel_lpe_audio_irq_handler() - forwards the LPE audio irq
274 * @dev_priv: the i915 drm device private data
275 *
276 * the LPE Audio irq is forwarded to the irq handler registered by LPE audio
277 * driver.
278 */
intel_lpe_audio_irq_handler(struct drm_i915_private * dev_priv)279 void intel_lpe_audio_irq_handler(struct drm_i915_private *dev_priv)
280 {
281 STUB();
282 #ifdef notyet
283 int ret;
284
285 if (!HAS_LPE_AUDIO(dev_priv))
286 return;
287
288 ret = generic_handle_irq(dev_priv->display.audio.lpe.irq);
289 if (ret)
290 drm_err_ratelimited(&dev_priv->drm,
291 "error handling LPE audio irq: %d\n", ret);
292 #endif
293 }
294
295 /**
296 * intel_lpe_audio_init() - detect and setup the bridge between HDMI LPE Audio
297 * driver and i915
298 * @dev_priv: the i915 drm device private data
299 *
300 * Return: 0 if successful. non-zero if detection or
301 * llocation/initialization fails
302 */
intel_lpe_audio_init(struct drm_i915_private * dev_priv)303 int intel_lpe_audio_init(struct drm_i915_private *dev_priv)
304 {
305 int ret = -ENODEV;
306
307 if (lpe_audio_detect(dev_priv)) {
308 ret = lpe_audio_setup(dev_priv);
309 if (ret < 0)
310 drm_err(&dev_priv->drm,
311 "failed to setup LPE Audio bridge\n");
312 }
313 return ret;
314 }
315
316 /**
317 * intel_lpe_audio_teardown() - destroy the bridge between HDMI LPE
318 * audio driver and i915
319 * @dev_priv: the i915 drm device private data
320 *
321 * release all the resources for LPE audio <-> i915 bridge.
322 */
intel_lpe_audio_teardown(struct drm_i915_private * dev_priv)323 void intel_lpe_audio_teardown(struct drm_i915_private *dev_priv)
324 {
325 STUB();
326 #ifdef notyet
327 if (!HAS_LPE_AUDIO(dev_priv))
328 return;
329
330 lpe_audio_platdev_destroy(dev_priv);
331
332 irq_free_desc(dev_priv->display.audio.lpe.irq);
333
334 dev_priv->display.audio.lpe.irq = -1;
335 dev_priv->display.audio.lpe.platdev = NULL;
336 #endif
337 }
338
339 /**
340 * intel_lpe_audio_notify() - notify lpe audio event
341 * audio driver and i915
342 * @dev_priv: the i915 drm device private data
343 * @cpu_transcoder: CPU transcoder
344 * @port: port
345 * @eld : ELD data
346 * @ls_clock: Link symbol clock in kHz
347 * @dp_output: Driving a DP output?
348 *
349 * Notify lpe audio driver of eld change.
350 */
intel_lpe_audio_notify(struct drm_i915_private * dev_priv,enum transcoder cpu_transcoder,enum port port,const void * eld,int ls_clock,bool dp_output)351 void intel_lpe_audio_notify(struct drm_i915_private *dev_priv,
352 enum transcoder cpu_transcoder, enum port port,
353 const void *eld, int ls_clock, bool dp_output)
354 {
355 #ifdef notyet
356 unsigned long irqflags;
357 struct intel_hdmi_lpe_audio_pdata *pdata;
358 struct intel_hdmi_lpe_audio_port_pdata *ppdata;
359 u32 audio_enable;
360
361 if (!HAS_LPE_AUDIO(dev_priv))
362 return;
363
364 pdata = dev_get_platdata(&dev_priv->display.audio.lpe.platdev->dev);
365 ppdata = &pdata->port[port - PORT_B];
366
367 spin_lock_irqsave(&pdata->lpe_audio_slock, irqflags);
368
369 audio_enable = intel_de_read(dev_priv, VLV_AUD_PORT_EN_DBG(port));
370
371 if (eld != NULL) {
372 memcpy(ppdata->eld, eld, HDMI_MAX_ELD_BYTES);
373 ppdata->pipe = cpu_transcoder;
374 ppdata->ls_clock = ls_clock;
375 ppdata->dp_output = dp_output;
376
377 /* Unmute the amp for both DP and HDMI */
378 intel_de_write(dev_priv, VLV_AUD_PORT_EN_DBG(port),
379 audio_enable & ~VLV_AMP_MUTE);
380 } else {
381 memset(ppdata->eld, 0, HDMI_MAX_ELD_BYTES);
382 ppdata->pipe = -1;
383 ppdata->ls_clock = 0;
384 ppdata->dp_output = false;
385
386 /* Mute the amp for both DP and HDMI */
387 intel_de_write(dev_priv, VLV_AUD_PORT_EN_DBG(port),
388 audio_enable | VLV_AMP_MUTE);
389 }
390
391 if (pdata->notify_audio_lpe)
392 pdata->notify_audio_lpe(dev_priv->display.audio.lpe.platdev, port - PORT_B);
393
394 spin_unlock_irqrestore(&pdata->lpe_audio_slock, irqflags);
395 #endif
396 }
397