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 "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 int irq = display->audio.lpe.irq; 174 175 irq_set_chip_and_handler_name(irq, &lpe_audio_irqchip, 176 handle_simple_irq, 177 "hdmi_lpe_audio_irq_handler"); 178 179 return 0; 180 } 181 182 static bool lpe_audio_detect(struct intel_display *display) 183 { 184 int lpe_present = false; 185 186 if (display->platform.valleyview || display->platform.cherryview) { 187 static const struct pci_device_id atom_hdaudio_ids[] = { 188 /* Baytrail */ 189 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x0f04)}, 190 /* Braswell */ 191 {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2284)}, 192 {} 193 }; 194 195 if (!pci_dev_present(atom_hdaudio_ids)) { 196 drm_info(display->drm, 197 "HDaudio controller not detected, using LPE audio instead\n"); 198 lpe_present = true; 199 } 200 } 201 return lpe_present; 202 } 203 204 static int lpe_audio_setup(struct intel_display *display) 205 { 206 int ret; 207 208 display->audio.lpe.irq = irq_alloc_desc(0); 209 if (display->audio.lpe.irq < 0) { 210 drm_err(display->drm, "Failed to allocate IRQ desc: %d\n", 211 display->audio.lpe.irq); 212 ret = display->audio.lpe.irq; 213 goto err; 214 } 215 216 drm_dbg(display->drm, "irq = %d\n", display->audio.lpe.irq); 217 218 ret = lpe_audio_irq_init(display); 219 220 if (ret) { 221 drm_err(display->drm, 222 "Failed to initialize irqchip for lpe audio: %d\n", 223 ret); 224 goto err_free_irq; 225 } 226 227 display->audio.lpe.platdev = lpe_audio_platdev_create(display); 228 229 if (IS_ERR(display->audio.lpe.platdev)) { 230 ret = PTR_ERR(display->audio.lpe.platdev); 231 drm_err(display->drm, 232 "Failed to create lpe audio platform device: %d\n", 233 ret); 234 goto err_free_irq; 235 } 236 237 /* enable chicken bit; at least this is required for Dell Wyse 3040 238 * with DP outputs (but only sometimes by some reason!) 239 */ 240 intel_de_write(display, VLV_AUD_CHICKEN_BIT_REG, 241 VLV_CHICKEN_BIT_DBG_ENABLE); 242 243 return 0; 244 err_free_irq: 245 irq_free_desc(display->audio.lpe.irq); 246 err: 247 display->audio.lpe.irq = -1; 248 display->audio.lpe.platdev = NULL; 249 return ret; 250 } 251 252 /** 253 * intel_lpe_audio_irq_handler() - forwards the LPE audio irq 254 * @display: display device 255 * 256 * the LPE Audio irq is forwarded to the irq handler registered by LPE audio 257 * driver. 258 */ 259 void intel_lpe_audio_irq_handler(struct intel_display *display) 260 { 261 int ret; 262 263 if (!HAS_LPE_AUDIO(display)) 264 return; 265 266 ret = generic_handle_irq(display->audio.lpe.irq); 267 if (ret) 268 drm_err_ratelimited(display->drm, 269 "error handling LPE audio irq: %d\n", ret); 270 } 271 272 /** 273 * intel_lpe_audio_init() - detect and setup the bridge between HDMI LPE Audio 274 * driver and i915 275 * @display: display device 276 * 277 * Return: 0 if successful. non-zero if detection or 278 * llocation/initialization fails 279 */ 280 int intel_lpe_audio_init(struct intel_display *display) 281 { 282 int ret = -ENODEV; 283 284 if (lpe_audio_detect(display)) { 285 ret = lpe_audio_setup(display); 286 if (ret < 0) 287 drm_err(display->drm, 288 "failed to setup LPE Audio bridge\n"); 289 } 290 return ret; 291 } 292 293 /** 294 * intel_lpe_audio_teardown() - destroy the bridge between HDMI LPE 295 * audio driver and i915 296 * @display: display device 297 * 298 * release all the resources for LPE audio <-> i915 bridge. 299 */ 300 void intel_lpe_audio_teardown(struct intel_display *display) 301 { 302 if (!HAS_LPE_AUDIO(display)) 303 return; 304 305 lpe_audio_platdev_destroy(display); 306 307 irq_free_desc(display->audio.lpe.irq); 308 309 display->audio.lpe.irq = -1; 310 display->audio.lpe.platdev = NULL; 311 } 312 313 /** 314 * intel_lpe_audio_notify() - notify lpe audio event 315 * audio driver and i915 316 * @display: display device 317 * @cpu_transcoder: CPU transcoder 318 * @port: port 319 * @eld : ELD data 320 * @ls_clock: Link symbol clock in kHz 321 * @dp_output: Driving a DP output? 322 * 323 * Notify lpe audio driver of eld change. 324 */ 325 void intel_lpe_audio_notify(struct intel_display *display, 326 enum transcoder cpu_transcoder, enum port port, 327 const void *eld, int ls_clock, bool dp_output) 328 { 329 unsigned long irqflags; 330 struct intel_hdmi_lpe_audio_pdata *pdata; 331 struct intel_hdmi_lpe_audio_port_pdata *ppdata; 332 u32 audio_enable; 333 334 if (!HAS_LPE_AUDIO(display)) 335 return; 336 337 pdata = dev_get_platdata(&display->audio.lpe.platdev->dev); 338 ppdata = &pdata->port[port - PORT_B]; 339 340 spin_lock_irqsave(&pdata->lpe_audio_slock, irqflags); 341 342 audio_enable = intel_de_read(display, VLV_AUD_PORT_EN_DBG(port)); 343 344 if (eld != NULL) { 345 memcpy(ppdata->eld, eld, HDMI_MAX_ELD_BYTES); 346 ppdata->pipe = cpu_transcoder; 347 ppdata->ls_clock = ls_clock; 348 ppdata->dp_output = dp_output; 349 350 /* Unmute the amp for both DP and HDMI */ 351 intel_de_write(display, VLV_AUD_PORT_EN_DBG(port), 352 audio_enable & ~VLV_AMP_MUTE); 353 } else { 354 memset(ppdata->eld, 0, HDMI_MAX_ELD_BYTES); 355 ppdata->pipe = -1; 356 ppdata->ls_clock = 0; 357 ppdata->dp_output = false; 358 359 /* Mute the amp for both DP and HDMI */ 360 intel_de_write(display, VLV_AUD_PORT_EN_DBG(port), 361 audio_enable | VLV_AMP_MUTE); 362 } 363 364 if (pdata->notify_audio_lpe) 365 pdata->notify_audio_lpe(display->audio.lpe.platdev, port - PORT_B); 366 367 spin_unlock_irqrestore(&pdata->lpe_audio_slock, irqflags); 368 } 369