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/intel_lpe_audio.h> 72 73 #include "i915_drv.h" 74 #include "i915_irq.h" 75 #include "intel_audio_regs.h" 76 #include "intel_de.h" 77 #include "intel_lpe_audio.h" 78 #include "intel_pci_config.h" 79 80 #define HAS_LPE_AUDIO(display) ((display)->audio.lpe.platdev) 81 82 static struct platform_device * 83 lpe_audio_platdev_create(struct intel_display *display) 84 { 85 struct pci_dev *pdev = to_pci_dev(display->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(sizeof(*pdata), GFP_KERNEL); 92 if (!pdata) 93 return ERR_PTR(-ENOMEM); 94 95 rsc = kcalloc(2, sizeof(*rsc), GFP_KERNEL); 96 if (!rsc) { 97 kfree(pdata); 98 return ERR_PTR(-ENOMEM); 99 } 100 101 rsc[0].start = display->audio.lpe.irq; 102 rsc[0].end = display->audio.lpe.irq; 103 rsc[0].flags = IORESOURCE_IRQ; 104 rsc[0].name = "hdmi-lpe-audio-irq"; 105 106 rsc[1].start = pci_resource_start(pdev, GEN4_GTTMMADR_BAR) + 107 I915_HDMI_LPE_AUDIO_BASE; 108 rsc[1].end = pci_resource_start(pdev, GEN4_GTTMMADR_BAR) + 109 I915_HDMI_LPE_AUDIO_BASE + I915_HDMI_LPE_AUDIO_SIZE - 1; 110 rsc[1].flags = IORESOURCE_MEM; 111 rsc[1].name = "hdmi-lpe-audio-mmio"; 112 113 pinfo.parent = display->drm->dev; 114 pinfo.name = "hdmi-lpe-audio"; 115 pinfo.id = -1; 116 pinfo.res = rsc; 117 pinfo.num_res = 2; 118 pinfo.data = pdata; 119 pinfo.size_data = sizeof(*pdata); 120 pinfo.dma_mask = DMA_BIT_MASK(32); 121 122 pdata->num_pipes = INTEL_NUM_PIPES(display); 123 pdata->num_ports = display->platform.cherryview ? 3 : 2; /* B,C,D or B,C */ 124 pdata->port[0].pipe = -1; 125 pdata->port[1].pipe = -1; 126 pdata->port[2].pipe = -1; 127 spin_lock_init(&pdata->lpe_audio_slock); 128 129 platdev = platform_device_register_full(&pinfo); 130 kfree(rsc); 131 kfree(pdata); 132 133 if (IS_ERR(platdev)) { 134 drm_err(display->drm, 135 "Failed to allocate LPE audio platform device\n"); 136 return platdev; 137 } 138 139 pm_runtime_no_callbacks(&platdev->dev); 140 141 return platdev; 142 } 143 144 static void lpe_audio_platdev_destroy(struct intel_display *display) 145 { 146 /* XXX Note that platform_device_register_full() allocates a dma_mask 147 * and never frees it. We can't free it here as we cannot guarantee 148 * this is the last reference (i.e. that the dma_mask will not be 149 * used after our unregister). So ee choose to leak the sizeof(u64) 150 * allocation here - it should be fixed in the platform_device rather 151 * than us fiddle with its internals. 152 */ 153 154 platform_device_unregister(display->audio.lpe.platdev); 155 } 156 157 static void lpe_audio_irq_unmask(struct irq_data *d) 158 { 159 } 160 161 static void lpe_audio_irq_mask(struct irq_data *d) 162 { 163 } 164 165 static struct irq_chip lpe_audio_irqchip = { 166 .name = "hdmi_lpe_audio_irqchip", 167 .irq_mask = lpe_audio_irq_mask, 168 .irq_unmask = lpe_audio_irq_unmask, 169 }; 170 171 static int lpe_audio_irq_init(struct intel_display *display) 172 { 173 struct drm_i915_private *dev_priv = to_i915(display->drm); 174 int irq = display->audio.lpe.irq; 175 176 drm_WARN_ON(display->drm, !intel_irqs_enabled(dev_priv)); 177 irq_set_chip_and_handler_name(irq, 178 &lpe_audio_irqchip, 179 handle_simple_irq, 180 "hdmi_lpe_audio_irq_handler"); 181 182 return irq_set_chip_data(irq, dev_priv); 183 } 184 185 static bool lpe_audio_detect(struct intel_display *display) 186 { 187 int lpe_present = false; 188 189 if (display->platform.valleyview || display->platform.cherryview) { 190 static const struct pci_device_id atom_hdaudio_ids[] = { 191 /* Baytrail */ 192 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x0f04)}, 193 /* Braswell */ 194 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2284)}, 195 {} 196 }; 197 198 if (!pci_dev_present(atom_hdaudio_ids)) { 199 drm_info(display->drm, 200 "HDaudio controller not detected, using LPE audio instead\n"); 201 lpe_present = true; 202 } 203 } 204 return lpe_present; 205 } 206 207 static int lpe_audio_setup(struct intel_display *display) 208 { 209 int ret; 210 211 display->audio.lpe.irq = irq_alloc_desc(0); 212 if (display->audio.lpe.irq < 0) { 213 drm_err(display->drm, "Failed to allocate IRQ desc: %d\n", 214 display->audio.lpe.irq); 215 ret = display->audio.lpe.irq; 216 goto err; 217 } 218 219 drm_dbg(display->drm, "irq = %d\n", display->audio.lpe.irq); 220 221 ret = lpe_audio_irq_init(display); 222 223 if (ret) { 224 drm_err(display->drm, 225 "Failed to initialize irqchip for lpe audio: %d\n", 226 ret); 227 goto err_free_irq; 228 } 229 230 display->audio.lpe.platdev = lpe_audio_platdev_create(display); 231 232 if (IS_ERR(display->audio.lpe.platdev)) { 233 ret = PTR_ERR(display->audio.lpe.platdev); 234 drm_err(display->drm, 235 "Failed to create lpe audio platform device: %d\n", 236 ret); 237 goto err_free_irq; 238 } 239 240 /* enable chicken bit; at least this is required for Dell Wyse 3040 241 * with DP outputs (but only sometimes by some reason!) 242 */ 243 intel_de_write(display, VLV_AUD_CHICKEN_BIT_REG, 244 VLV_CHICKEN_BIT_DBG_ENABLE); 245 246 return 0; 247 err_free_irq: 248 irq_free_desc(display->audio.lpe.irq); 249 err: 250 display->audio.lpe.irq = -1; 251 display->audio.lpe.platdev = NULL; 252 return ret; 253 } 254 255 /** 256 * intel_lpe_audio_irq_handler() - forwards the LPE audio irq 257 * @display: display device 258 * 259 * the LPE Audio irq is forwarded to the irq handler registered by LPE audio 260 * driver. 261 */ 262 void intel_lpe_audio_irq_handler(struct intel_display *display) 263 { 264 int ret; 265 266 if (!HAS_LPE_AUDIO(display)) 267 return; 268 269 ret = generic_handle_irq(display->audio.lpe.irq); 270 if (ret) 271 drm_err_ratelimited(display->drm, 272 "error handling LPE audio irq: %d\n", ret); 273 } 274 275 /** 276 * intel_lpe_audio_init() - detect and setup the bridge between HDMI LPE Audio 277 * driver and i915 278 * @display: display device 279 * 280 * Return: 0 if successful. non-zero if detection or 281 * llocation/initialization fails 282 */ 283 int intel_lpe_audio_init(struct intel_display *display) 284 { 285 int ret = -ENODEV; 286 287 if (lpe_audio_detect(display)) { 288 ret = lpe_audio_setup(display); 289 if (ret < 0) 290 drm_err(display->drm, 291 "failed to setup LPE Audio bridge\n"); 292 } 293 return ret; 294 } 295 296 /** 297 * intel_lpe_audio_teardown() - destroy the bridge between HDMI LPE 298 * audio driver and i915 299 * @display: display device 300 * 301 * release all the resources for LPE audio <-> i915 bridge. 302 */ 303 void intel_lpe_audio_teardown(struct intel_display *display) 304 { 305 if (!HAS_LPE_AUDIO(display)) 306 return; 307 308 lpe_audio_platdev_destroy(display); 309 310 irq_free_desc(display->audio.lpe.irq); 311 312 display->audio.lpe.irq = -1; 313 display->audio.lpe.platdev = NULL; 314 } 315 316 /** 317 * intel_lpe_audio_notify() - notify lpe audio event 318 * audio driver and i915 319 * @display: display device 320 * @cpu_transcoder: CPU transcoder 321 * @port: port 322 * @eld : ELD data 323 * @ls_clock: Link symbol clock in kHz 324 * @dp_output: Driving a DP output? 325 * 326 * Notify lpe audio driver of eld change. 327 */ 328 void intel_lpe_audio_notify(struct intel_display *display, 329 enum transcoder cpu_transcoder, enum port port, 330 const void *eld, int ls_clock, bool dp_output) 331 { 332 unsigned long irqflags; 333 struct intel_hdmi_lpe_audio_pdata *pdata; 334 struct intel_hdmi_lpe_audio_port_pdata *ppdata; 335 u32 audio_enable; 336 337 if (!HAS_LPE_AUDIO(display)) 338 return; 339 340 pdata = dev_get_platdata(&display->audio.lpe.platdev->dev); 341 ppdata = &pdata->port[port - PORT_B]; 342 343 spin_lock_irqsave(&pdata->lpe_audio_slock, irqflags); 344 345 audio_enable = intel_de_read(display, VLV_AUD_PORT_EN_DBG(port)); 346 347 if (eld != NULL) { 348 memcpy(ppdata->eld, eld, HDMI_MAX_ELD_BYTES); 349 ppdata->pipe = cpu_transcoder; 350 ppdata->ls_clock = ls_clock; 351 ppdata->dp_output = dp_output; 352 353 /* Unmute the amp for both DP and HDMI */ 354 intel_de_write(display, VLV_AUD_PORT_EN_DBG(port), 355 audio_enable & ~VLV_AMP_MUTE); 356 } else { 357 memset(ppdata->eld, 0, HDMI_MAX_ELD_BYTES); 358 ppdata->pipe = -1; 359 ppdata->ls_clock = 0; 360 ppdata->dp_output = false; 361 362 /* Mute the amp for both DP and HDMI */ 363 intel_de_write(display, VLV_AUD_PORT_EN_DBG(port), 364 audio_enable | VLV_AMP_MUTE); 365 } 366 367 if (pdata->notify_audio_lpe) 368 pdata->notify_audio_lpe(display->audio.lpe.platdev, port - PORT_B); 369 370 spin_unlock_irqrestore(&pdata->lpe_audio_slock, irqflags); 371 } 372