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
82static struct platform_device *
83lpe_audio_platdev_create(struct drm_i915_private *dev_priv)
84{
85 struct pci_dev *pdev = to_pci_dev(dev_priv->drm.dev);
86 struct platform_device_info pinfo = {};
87 struct resource *rsc;
88 struct platform_device *platdev;
89 struct intel_hdmi_lpe_audio_pdata *pdata;
90
91 pdata = kzalloc(size: sizeof(*pdata), GFP_KERNEL);
92 if (!pdata)
93 return ERR_PTR(error: -ENOMEM);
94
95 rsc = kcalloc(n: 2, size: sizeof(*rsc), GFP_KERNEL);
96 if (!rsc) {
97 kfree(objp: pdata);
98 return ERR_PTR(error: -ENOMEM);
99 }
100
101 rsc[0].start = rsc[0].end = dev_priv->display.audio.lpe.irq;
102 rsc[0].flags = IORESOURCE_IRQ;
103 rsc[0].name = "hdmi-lpe-audio-irq";
104
105 rsc[1].start = pci_resource_start(pdev, GEN4_GTTMMADR_BAR) +
106 I915_HDMI_LPE_AUDIO_BASE;
107 rsc[1].end = pci_resource_start(pdev, GEN4_GTTMMADR_BAR) +
108 I915_HDMI_LPE_AUDIO_BASE + I915_HDMI_LPE_AUDIO_SIZE - 1;
109 rsc[1].flags = IORESOURCE_MEM;
110 rsc[1].name = "hdmi-lpe-audio-mmio";
111
112 pinfo.parent = dev_priv->drm.dev;
113 pinfo.name = "hdmi-lpe-audio";
114 pinfo.id = -1;
115 pinfo.res = rsc;
116 pinfo.num_res = 2;
117 pinfo.data = pdata;
118 pinfo.size_data = sizeof(*pdata);
119 pinfo.dma_mask = DMA_BIT_MASK(32);
120
121 pdata->num_pipes = INTEL_NUM_PIPES(dev_priv);
122 pdata->num_ports = IS_CHERRYVIEW(dev_priv) ? 3 : 2; /* B,C,D or B,C */
123 pdata->port[0].pipe = -1;
124 pdata->port[1].pipe = -1;
125 pdata->port[2].pipe = -1;
126 spin_lock_init(&pdata->lpe_audio_slock);
127
128 platdev = platform_device_register_full(pdevinfo: &pinfo);
129 kfree(objp: rsc);
130 kfree(objp: pdata);
131
132 if (IS_ERR(ptr: platdev)) {
133 drm_err(&dev_priv->drm,
134 "Failed to allocate LPE audio platform device\n");
135 return platdev;
136 }
137
138 pm_runtime_no_callbacks(dev: &platdev->dev);
139
140 return platdev;
141}
142
143static void lpe_audio_platdev_destroy(struct drm_i915_private *dev_priv)
144{
145 /* XXX Note that platform_device_register_full() allocates a dma_mask
146 * and never frees it. We can't free it here as we cannot guarantee
147 * this is the last reference (i.e. that the dma_mask will not be
148 * used after our unregister). So ee choose to leak the sizeof(u64)
149 * allocation here - it should be fixed in the platform_device rather
150 * than us fiddle with its internals.
151 */
152
153 platform_device_unregister(dev_priv->display.audio.lpe.platdev);
154}
155
156static void lpe_audio_irq_unmask(struct irq_data *d)
157{
158}
159
160static void lpe_audio_irq_mask(struct irq_data *d)
161{
162}
163
164static struct irq_chip lpe_audio_irqchip = {
165 .name = "hdmi_lpe_audio_irqchip",
166 .irq_mask = lpe_audio_irq_mask,
167 .irq_unmask = lpe_audio_irq_unmask,
168};
169
170static int lpe_audio_irq_init(struct drm_i915_private *dev_priv)
171{
172 int irq = dev_priv->display.audio.lpe.irq;
173
174 drm_WARN_ON(&dev_priv->drm, !intel_irqs_enabled(dev_priv));
175 irq_set_chip_and_handler_name(irq,
176 chip: &lpe_audio_irqchip,
177 handle: handle_simple_irq,
178 name: "hdmi_lpe_audio_irq_handler");
179
180 return irq_set_chip_data(irq, data: dev_priv);
181}
182
183static bool lpe_audio_detect(struct drm_i915_private *dev_priv)
184{
185 int lpe_present = false;
186
187 if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
188 static const struct pci_device_id atom_hdaudio_ids[] = {
189 /* Baytrail */
190 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x0f04)},
191 /* Braswell */
192 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2284)},
193 {}
194 };
195
196 if (!pci_dev_present(ids: atom_hdaudio_ids)) {
197 drm_info(&dev_priv->drm,
198 "HDaudio controller not detected, using LPE audio instead\n");
199 lpe_present = true;
200 }
201 }
202 return lpe_present;
203}
204
205static int lpe_audio_setup(struct drm_i915_private *dev_priv)
206{
207 int ret;
208
209 dev_priv->display.audio.lpe.irq = irq_alloc_desc(0);
210 if (dev_priv->display.audio.lpe.irq < 0) {
211 drm_err(&dev_priv->drm, "Failed to allocate IRQ desc: %d\n",
212 dev_priv->display.audio.lpe.irq);
213 ret = dev_priv->display.audio.lpe.irq;
214 goto err;
215 }
216
217 drm_dbg(&dev_priv->drm, "irq = %d\n", dev_priv->display.audio.lpe.irq);
218
219 ret = lpe_audio_irq_init(dev_priv);
220
221 if (ret) {
222 drm_err(&dev_priv->drm,
223 "Failed to initialize irqchip for lpe audio: %d\n",
224 ret);
225 goto err_free_irq;
226 }
227
228 dev_priv->display.audio.lpe.platdev = lpe_audio_platdev_create(dev_priv);
229
230 if (IS_ERR(ptr: dev_priv->display.audio.lpe.platdev)) {
231 ret = PTR_ERR(ptr: dev_priv->display.audio.lpe.platdev);
232 drm_err(&dev_priv->drm,
233 "Failed to create lpe audio platform device: %d\n",
234 ret);
235 goto err_free_irq;
236 }
237
238 /* enable chicken bit; at least this is required for Dell Wyse 3040
239 * with DP outputs (but only sometimes by some reason!)
240 */
241 intel_de_write(i915: dev_priv, VLV_AUD_CHICKEN_BIT_REG,
242 VLV_CHICKEN_BIT_DBG_ENABLE);
243
244 return 0;
245err_free_irq:
246 irq_free_desc(irq: dev_priv->display.audio.lpe.irq);
247err:
248 dev_priv->display.audio.lpe.irq = -1;
249 dev_priv->display.audio.lpe.platdev = NULL;
250 return ret;
251}
252
253/**
254 * intel_lpe_audio_irq_handler() - forwards the LPE audio irq
255 * @dev_priv: the i915 drm device private data
256 *
257 * the LPE Audio irq is forwarded to the irq handler registered by LPE audio
258 * driver.
259 */
260void intel_lpe_audio_irq_handler(struct drm_i915_private *dev_priv)
261{
262 int ret;
263
264 if (!HAS_LPE_AUDIO(dev_priv))
265 return;
266
267 ret = generic_handle_irq(irq: dev_priv->display.audio.lpe.irq);
268 if (ret)
269 drm_err_ratelimited(&dev_priv->drm,
270 "error handling LPE audio irq: %d\n", ret);
271}
272
273/**
274 * intel_lpe_audio_init() - detect and setup the bridge between HDMI LPE Audio
275 * driver and i915
276 * @dev_priv: the i915 drm device private data
277 *
278 * Return: 0 if successful. non-zero if detection or
279 * llocation/initialization fails
280 */
281int intel_lpe_audio_init(struct drm_i915_private *dev_priv)
282{
283 int ret = -ENODEV;
284
285 if (lpe_audio_detect(dev_priv)) {
286 ret = lpe_audio_setup(dev_priv);
287 if (ret < 0)
288 drm_err(&dev_priv->drm,
289 "failed to setup LPE Audio bridge\n");
290 }
291 return ret;
292}
293
294/**
295 * intel_lpe_audio_teardown() - destroy the bridge between HDMI LPE
296 * audio driver and i915
297 * @dev_priv: the i915 drm device private data
298 *
299 * release all the resources for LPE audio <-> i915 bridge.
300 */
301void intel_lpe_audio_teardown(struct drm_i915_private *dev_priv)
302{
303 if (!HAS_LPE_AUDIO(dev_priv))
304 return;
305
306 lpe_audio_platdev_destroy(dev_priv);
307
308 irq_free_desc(irq: dev_priv->display.audio.lpe.irq);
309
310 dev_priv->display.audio.lpe.irq = -1;
311 dev_priv->display.audio.lpe.platdev = NULL;
312}
313
314/**
315 * intel_lpe_audio_notify() - notify lpe audio event
316 * audio driver and i915
317 * @dev_priv: the i915 drm device private data
318 * @cpu_transcoder: CPU transcoder
319 * @port: port
320 * @eld : ELD data
321 * @ls_clock: Link symbol clock in kHz
322 * @dp_output: Driving a DP output?
323 *
324 * Notify lpe audio driver of eld change.
325 */
326void intel_lpe_audio_notify(struct drm_i915_private *dev_priv,
327 enum transcoder cpu_transcoder, enum port port,
328 const void *eld, int ls_clock, bool dp_output)
329{
330 unsigned long irqflags;
331 struct intel_hdmi_lpe_audio_pdata *pdata;
332 struct intel_hdmi_lpe_audio_port_pdata *ppdata;
333 u32 audio_enable;
334
335 if (!HAS_LPE_AUDIO(dev_priv))
336 return;
337
338 pdata = dev_get_platdata(dev: &dev_priv->display.audio.lpe.platdev->dev);
339 ppdata = &pdata->port[port - PORT_B];
340
341 spin_lock_irqsave(&pdata->lpe_audio_slock, irqflags);
342
343 audio_enable = intel_de_read(i915: dev_priv, VLV_AUD_PORT_EN_DBG(port));
344
345 if (eld != NULL) {
346 memcpy(ppdata->eld, eld, HDMI_MAX_ELD_BYTES);
347 ppdata->pipe = cpu_transcoder;
348 ppdata->ls_clock = ls_clock;
349 ppdata->dp_output = dp_output;
350
351 /* Unmute the amp for both DP and HDMI */
352 intel_de_write(i915: dev_priv, VLV_AUD_PORT_EN_DBG(port),
353 val: audio_enable & ~VLV_AMP_MUTE);
354 } else {
355 memset(ppdata->eld, 0, HDMI_MAX_ELD_BYTES);
356 ppdata->pipe = -1;
357 ppdata->ls_clock = 0;
358 ppdata->dp_output = false;
359
360 /* Mute the amp for both DP and HDMI */
361 intel_de_write(i915: dev_priv, VLV_AUD_PORT_EN_DBG(port),
362 val: audio_enable | VLV_AMP_MUTE);
363 }
364
365 if (pdata->notify_audio_lpe)
366 pdata->notify_audio_lpe(dev_priv->display.audio.lpe.platdev, port - PORT_B);
367
368 spin_unlock_irqrestore(lock: &pdata->lpe_audio_slock, flags: irqflags);
369}
370

source code of linux/drivers/gpu/drm/i915/display/intel_lpe_audio.c