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/drm_print.h>
72 #include <drm/intel/intel_lpe_audio.h>
73
74 #include "intel_audio_regs.h"
75 #include "intel_de.h"
76 #include "intel_lpe_audio.h"
77 #include "intel_pci_config.h"
78
79 #define HAS_LPE_AUDIO(display) ((display)->audio.lpe.platdev)
80
81 static struct platform_device *
lpe_audio_platdev_create(struct intel_display * display)82 lpe_audio_platdev_create(struct intel_display *display)
83 {
84 struct pci_dev *pdev = to_pci_dev(display->drm->dev);
85 struct platform_device_info pinfo = {};
86 struct resource *rsc;
87 struct platform_device *platdev;
88 struct intel_hdmi_lpe_audio_pdata *pdata;
89
90 pdata = kzalloc_obj(*pdata);
91 if (!pdata)
92 return ERR_PTR(-ENOMEM);
93
94 rsc = kzalloc_objs(*rsc, 2);
95 if (!rsc) {
96 kfree(pdata);
97 return ERR_PTR(-ENOMEM);
98 }
99
100 rsc[0].start = display->audio.lpe.irq;
101 rsc[0].end = 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 = display->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(display);
122 pdata->num_ports = display->platform.cherryview ? 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(&pinfo);
129 kfree(rsc);
130 kfree(pdata);
131
132 if (IS_ERR(platdev)) {
133 drm_err(display->drm,
134 "Failed to allocate LPE audio platform device\n");
135 return platdev;
136 }
137
138 pm_runtime_no_callbacks(&platdev->dev);
139
140 return platdev;
141 }
142
lpe_audio_platdev_destroy(struct intel_display * display)143 static void lpe_audio_platdev_destroy(struct intel_display *display)
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(display->audio.lpe.platdev);
154 }
155
lpe_audio_irq_unmask(struct irq_data * d)156 static void lpe_audio_irq_unmask(struct irq_data *d)
157 {
158 }
159
lpe_audio_irq_mask(struct irq_data * d)160 static void lpe_audio_irq_mask(struct irq_data *d)
161 {
162 }
163
164 static 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
lpe_audio_irq_init(struct intel_display * display)170 static int lpe_audio_irq_init(struct intel_display *display)
171 {
172 int irq = display->audio.lpe.irq;
173
174 irq_set_chip_and_handler_name(irq, &lpe_audio_irqchip,
175 handle_simple_irq,
176 "hdmi_lpe_audio_irq_handler");
177
178 return 0;
179 }
180
lpe_audio_detect(struct intel_display * display)181 static bool lpe_audio_detect(struct intel_display *display)
182 {
183 int lpe_present = false;
184
185 if (display->platform.valleyview || display->platform.cherryview) {
186 static const struct pci_device_id atom_hdaudio_ids[] = {
187 /* Baytrail */
188 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x0f04)},
189 /* Braswell */
190 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2284)},
191 {}
192 };
193
194 if (!pci_dev_present(atom_hdaudio_ids)) {
195 drm_info(display->drm,
196 "HDaudio controller not detected, using LPE audio instead\n");
197 lpe_present = true;
198 }
199 }
200 return lpe_present;
201 }
202
lpe_audio_setup(struct intel_display * display)203 static int lpe_audio_setup(struct intel_display *display)
204 {
205 int ret;
206
207 display->audio.lpe.irq = irq_alloc_desc(0);
208 if (display->audio.lpe.irq < 0) {
209 drm_err(display->drm, "Failed to allocate IRQ desc: %d\n",
210 display->audio.lpe.irq);
211 ret = display->audio.lpe.irq;
212 goto err;
213 }
214
215 drm_dbg(display->drm, "irq = %d\n", display->audio.lpe.irq);
216
217 ret = lpe_audio_irq_init(display);
218
219 if (ret) {
220 drm_err(display->drm,
221 "Failed to initialize irqchip for lpe audio: %d\n",
222 ret);
223 goto err_free_irq;
224 }
225
226 display->audio.lpe.platdev = lpe_audio_platdev_create(display);
227
228 if (IS_ERR(display->audio.lpe.platdev)) {
229 ret = PTR_ERR(display->audio.lpe.platdev);
230 drm_err(display->drm,
231 "Failed to create lpe audio platform device: %d\n",
232 ret);
233 goto err_free_irq;
234 }
235
236 /* enable chicken bit; at least this is required for Dell Wyse 3040
237 * with DP outputs (but only sometimes by some reason!)
238 */
239 intel_de_write(display, VLV_AUD_CHICKEN_BIT_REG,
240 VLV_CHICKEN_BIT_DBG_ENABLE);
241
242 return 0;
243 err_free_irq:
244 irq_free_desc(display->audio.lpe.irq);
245 err:
246 display->audio.lpe.irq = -1;
247 display->audio.lpe.platdev = NULL;
248 return ret;
249 }
250
251 /**
252 * intel_lpe_audio_irq_handler() - forwards the LPE audio irq
253 * @display: display device
254 *
255 * the LPE Audio irq is forwarded to the irq handler registered by LPE audio
256 * driver.
257 */
intel_lpe_audio_irq_handler(struct intel_display * display)258 void intel_lpe_audio_irq_handler(struct intel_display *display)
259 {
260 int ret;
261
262 if (!HAS_LPE_AUDIO(display))
263 return;
264
265 ret = generic_handle_irq(display->audio.lpe.irq);
266 if (ret)
267 drm_err_ratelimited(display->drm,
268 "error handling LPE audio irq: %d\n", ret);
269 }
270
271 /**
272 * intel_lpe_audio_init() - detect and setup the bridge between HDMI LPE Audio
273 * driver and i915
274 * @display: display device
275 *
276 * Return: 0 if successful. non-zero if detection or
277 * llocation/initialization fails
278 */
intel_lpe_audio_init(struct intel_display * display)279 int intel_lpe_audio_init(struct intel_display *display)
280 {
281 int ret = -ENODEV;
282
283 if (lpe_audio_detect(display)) {
284 ret = lpe_audio_setup(display);
285 if (ret < 0)
286 drm_err(display->drm,
287 "failed to setup LPE Audio bridge\n");
288 }
289 return ret;
290 }
291
292 /**
293 * intel_lpe_audio_teardown() - destroy the bridge between HDMI LPE
294 * audio driver and i915
295 * @display: display device
296 *
297 * release all the resources for LPE audio <-> i915 bridge.
298 */
intel_lpe_audio_teardown(struct intel_display * display)299 void intel_lpe_audio_teardown(struct intel_display *display)
300 {
301 if (!HAS_LPE_AUDIO(display))
302 return;
303
304 lpe_audio_platdev_destroy(display);
305
306 irq_free_desc(display->audio.lpe.irq);
307
308 display->audio.lpe.irq = -1;
309 display->audio.lpe.platdev = NULL;
310 }
311
312 /**
313 * intel_lpe_audio_notify() - notify lpe audio event
314 * audio driver and i915
315 * @display: display device
316 * @cpu_transcoder: CPU transcoder
317 * @port: port
318 * @eld : ELD data
319 * @ls_clock: Link symbol clock in kHz
320 * @dp_output: Driving a DP output?
321 *
322 * Notify lpe audio driver of eld change.
323 */
intel_lpe_audio_notify(struct intel_display * display,enum transcoder cpu_transcoder,enum port port,const void * eld,int ls_clock,bool dp_output)324 void intel_lpe_audio_notify(struct intel_display *display,
325 enum transcoder cpu_transcoder, enum port port,
326 const void *eld, int ls_clock, bool dp_output)
327 {
328 unsigned long irqflags;
329 struct intel_hdmi_lpe_audio_pdata *pdata;
330 struct intel_hdmi_lpe_audio_port_pdata *ppdata;
331 u32 audio_enable;
332
333 if (!HAS_LPE_AUDIO(display))
334 return;
335
336 pdata = dev_get_platdata(&display->audio.lpe.platdev->dev);
337 ppdata = &pdata->port[port - PORT_B];
338
339 spin_lock_irqsave(&pdata->lpe_audio_slock, irqflags);
340
341 audio_enable = intel_de_read(display, VLV_AUD_PORT_EN_DBG(port));
342
343 if (eld != NULL) {
344 memcpy(ppdata->eld, eld, HDMI_MAX_ELD_BYTES);
345 ppdata->pipe = cpu_transcoder;
346 ppdata->ls_clock = ls_clock;
347 ppdata->dp_output = dp_output;
348
349 /* Unmute the amp for both DP and HDMI */
350 intel_de_write(display, VLV_AUD_PORT_EN_DBG(port),
351 audio_enable & ~VLV_AMP_MUTE);
352 } else {
353 memset(ppdata->eld, 0, HDMI_MAX_ELD_BYTES);
354 ppdata->pipe = -1;
355 ppdata->ls_clock = 0;
356 ppdata->dp_output = false;
357
358 /* Mute the amp for both DP and HDMI */
359 intel_de_write(display, VLV_AUD_PORT_EN_DBG(port),
360 audio_enable | VLV_AMP_MUTE);
361 }
362
363 if (pdata->notify_audio_lpe)
364 pdata->notify_audio_lpe(display->audio.lpe.platdev, port - PORT_B);
365
366 spin_unlock_irqrestore(&pdata->lpe_audio_slock, irqflags);
367 }
368