1 // SPDX-License-Identifier: MIT
3 * Copyright © 2020-2021 Intel Corporation
7 #include "i915_trace.h"
8 #include "intel_display_types.h"
9 #include "intel_dp_aux.h"
10 #include "intel_pps.h"
13 u32 intel_dp_pack_aux(const u8 *src, int src_bytes)
20 for (i = 0; i < src_bytes; i++)
21 v |= ((u32)src[i]) << ((3 - i) * 8);
25 static void intel_dp_unpack_aux(u32 src, u8 *dst, int dst_bytes)
31 for (i = 0; i < dst_bytes; i++)
32 dst[i] = src >> ((3 - i) * 8);
36 intel_dp_aux_wait_done(struct intel_dp *intel_dp)
38 struct drm_i915_private *i915 = dp_to_i915(intel_dp);
39 i915_reg_t ch_ctl = intel_dp->aux_ch_ctl_reg(intel_dp);
40 const unsigned int timeout_ms = 10;
44 #define C (((status = intel_uncore_read_notrace(&i915->uncore, ch_ctl)) & DP_AUX_CH_CTL_SEND_BUSY) == 0)
45 done = wait_event_timeout(i915->gmbus_wait_queue, C,
46 msecs_to_jiffies_timeout(timeout_ms));
48 /* just trace the final value */
49 trace_i915_reg_rw(false, ch_ctl, status, sizeof(status), true);
53 "%s: did not complete or timeout within %ums (status 0x%08x)\n",
54 intel_dp->aux.name, timeout_ms, status);
60 static u32 g4x_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
62 struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
68 * The clock divider is based off the hrawclk, and would like to run at
69 * 2MHz. So, take the hrawclk value and divide by 2000 and use that
71 return DIV_ROUND_CLOSEST(RUNTIME_INFO(dev_priv)->rawclk_freq, 2000);
74 static u32 ilk_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
76 struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
77 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
84 * The clock divider is based off the cdclk or PCH rawclk, and would
85 * like to run at 2MHz. So, take the cdclk or PCH rawclk value and
86 * divide by 2000 and use that
88 if (dig_port->aux_ch == AUX_CH_A)
89 freq = dev_priv->cdclk.hw.cdclk;
91 freq = RUNTIME_INFO(dev_priv)->rawclk_freq;
92 return DIV_ROUND_CLOSEST(freq, 2000);
95 static u32 hsw_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
97 struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
98 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
100 if (dig_port->aux_ch != AUX_CH_A && HAS_PCH_LPT_H(dev_priv)) {
101 /* Workaround for non-ULT HSW */
109 return ilk_get_aux_clock_divider(intel_dp, index);
112 static u32 skl_get_aux_clock_divider(struct intel_dp *intel_dp, int index)
115 * SKL doesn't need us to program the AUX clock divider (Hardware will
116 * derive the clock from CDCLK automatically). We still implement the
117 * get_aux_clock_divider vfunc to plug-in into the existing code.
119 return index ? 0 : 1;
122 static u32 g4x_get_aux_send_ctl(struct intel_dp *intel_dp,
124 u32 aux_clock_divider)
126 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
127 struct drm_i915_private *dev_priv =
128 to_i915(dig_port->base.base.dev);
131 /* Max timeout value on G4x-BDW: 1.6ms */
132 if (IS_BROADWELL(dev_priv))
133 timeout = DP_AUX_CH_CTL_TIME_OUT_600us;
135 timeout = DP_AUX_CH_CTL_TIME_OUT_400us;
137 return DP_AUX_CH_CTL_SEND_BUSY |
139 DP_AUX_CH_CTL_INTERRUPT |
140 DP_AUX_CH_CTL_TIME_OUT_ERROR |
142 DP_AUX_CH_CTL_RECEIVE_ERROR |
143 (send_bytes << DP_AUX_CH_CTL_MESSAGE_SIZE_SHIFT) |
144 (3 << DP_AUX_CH_CTL_PRECHARGE_2US_SHIFT) |
145 (aux_clock_divider << DP_AUX_CH_CTL_BIT_CLOCK_2X_SHIFT);
148 static u32 skl_get_aux_send_ctl(struct intel_dp *intel_dp,
152 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
153 struct drm_i915_private *i915 =
154 to_i915(dig_port->base.base.dev);
155 enum phy phy = intel_port_to_phy(i915, dig_port->base.port);
159 * Max timeout values:
164 ret = DP_AUX_CH_CTL_SEND_BUSY |
166 DP_AUX_CH_CTL_INTERRUPT |
167 DP_AUX_CH_CTL_TIME_OUT_ERROR |
168 DP_AUX_CH_CTL_TIME_OUT_MAX |
169 DP_AUX_CH_CTL_RECEIVE_ERROR |
170 (send_bytes << DP_AUX_CH_CTL_MESSAGE_SIZE_SHIFT) |
171 DP_AUX_CH_CTL_FW_SYNC_PULSE_SKL(32) |
172 DP_AUX_CH_CTL_SYNC_PULSE_SKL(32);
174 if (intel_phy_is_tc(i915, phy) &&
175 dig_port->tc_mode == TC_PORT_TBT_ALT)
176 ret |= DP_AUX_CH_CTL_TBT_IO;
182 intel_dp_aux_xfer(struct intel_dp *intel_dp,
183 const u8 *send, int send_bytes,
184 u8 *recv, int recv_size,
185 u32 aux_send_ctl_flags)
187 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
188 struct drm_i915_private *i915 =
189 to_i915(dig_port->base.base.dev);
190 struct intel_uncore *uncore = &i915->uncore;
191 enum phy phy = intel_port_to_phy(i915, dig_port->base.port);
192 bool is_tc_port = intel_phy_is_tc(i915, phy);
193 i915_reg_t ch_ctl, ch_data[5];
194 u32 aux_clock_divider;
195 enum intel_display_power_domain aux_domain;
196 intel_wakeref_t aux_wakeref;
197 intel_wakeref_t pps_wakeref;
198 int i, ret, recv_bytes;
203 ch_ctl = intel_dp->aux_ch_ctl_reg(intel_dp);
204 for (i = 0; i < ARRAY_SIZE(ch_data); i++)
205 ch_data[i] = intel_dp->aux_ch_data_reg(intel_dp, i);
208 intel_tc_port_lock(dig_port);
210 aux_domain = intel_aux_power_domain(dig_port);
212 aux_wakeref = intel_display_power_get(i915, aux_domain);
213 pps_wakeref = intel_pps_lock(intel_dp);
216 * We will be called with VDD already enabled for dpcd/edid/oui reads.
217 * In such cases we want to leave VDD enabled and it's up to upper layers
218 * to turn it off. But for eg. i2c-dev access we need to turn it on/off
221 vdd = intel_pps_vdd_on_unlocked(intel_dp);
224 * dp aux is extremely sensitive to irq latency, hence request the
225 * lowest possible wakeup latency and so prevent the cpu from going into
228 cpu_latency_qos_update_request(&intel_dp->pm_qos, 0);
230 intel_pps_check_power_unlocked(intel_dp);
232 /* Try to wait for any previous AUX channel activity */
233 for (try = 0; try < 3; try++) {
234 status = intel_uncore_read_notrace(uncore, ch_ctl);
235 if ((status & DP_AUX_CH_CTL_SEND_BUSY) == 0)
239 /* just trace the final value */
240 trace_i915_reg_rw(false, ch_ctl, status, sizeof(status), true);
243 const u32 status = intel_uncore_read(uncore, ch_ctl);
245 if (status != intel_dp->aux_busy_last_status) {
246 drm_WARN(&i915->drm, 1,
247 "%s: not started (status 0x%08x)\n",
248 intel_dp->aux.name, status);
249 intel_dp->aux_busy_last_status = status;
256 /* Only 5 data registers! */
257 if (drm_WARN_ON(&i915->drm, send_bytes > 20 || recv_size > 20)) {
262 while ((aux_clock_divider = intel_dp->get_aux_clock_divider(intel_dp, clock++))) {
263 u32 send_ctl = intel_dp->get_aux_send_ctl(intel_dp,
267 send_ctl |= aux_send_ctl_flags;
269 /* Must try at least 3 times according to DP spec */
270 for (try = 0; try < 5; try++) {
271 /* Load the send data into the aux channel data registers */
272 for (i = 0; i < send_bytes; i += 4)
273 intel_uncore_write(uncore,
275 intel_dp_pack_aux(send + i,
278 /* Send the command and wait for it to complete */
279 intel_uncore_write(uncore, ch_ctl, send_ctl);
281 status = intel_dp_aux_wait_done(intel_dp);
283 /* Clear done status and any errors */
284 intel_uncore_write(uncore,
288 DP_AUX_CH_CTL_TIME_OUT_ERROR |
289 DP_AUX_CH_CTL_RECEIVE_ERROR);
292 * DP CTS 1.2 Core Rev 1.1, 4.2.1.1 & 4.2.1.2
293 * 400us delay required for errors and timeouts
294 * Timeout errors from the HW already meet this
295 * requirement so skip to next iteration
297 if (status & DP_AUX_CH_CTL_TIME_OUT_ERROR)
300 if (status & DP_AUX_CH_CTL_RECEIVE_ERROR) {
301 usleep_range(400, 500);
304 if (status & DP_AUX_CH_CTL_DONE)
309 if ((status & DP_AUX_CH_CTL_DONE) == 0) {
310 drm_err(&i915->drm, "%s: not done (status 0x%08x)\n",
311 intel_dp->aux.name, status);
318 * Check for timeout or receive error. Timeouts occur when the sink is
321 if (status & DP_AUX_CH_CTL_RECEIVE_ERROR) {
322 drm_err(&i915->drm, "%s: receive error (status 0x%08x)\n",
323 intel_dp->aux.name, status);
329 * Timeouts occur when the device isn't connected, so they're "normal"
330 * -- don't fill the kernel log with these
332 if (status & DP_AUX_CH_CTL_TIME_OUT_ERROR) {
333 drm_dbg_kms(&i915->drm, "%s: timeout (status 0x%08x)\n",
334 intel_dp->aux.name, status);
339 /* Unload any bytes sent back from the other side */
340 recv_bytes = ((status & DP_AUX_CH_CTL_MESSAGE_SIZE_MASK) >>
341 DP_AUX_CH_CTL_MESSAGE_SIZE_SHIFT);
344 * By BSpec: "Message sizes of 0 or >20 are not allowed."
345 * We have no idea of what happened so we return -EBUSY so
346 * drm layer takes care for the necessary retries.
348 if (recv_bytes == 0 || recv_bytes > 20) {
349 drm_dbg_kms(&i915->drm,
350 "%s: Forbidden recv_bytes = %d on aux transaction\n",
351 intel_dp->aux.name, recv_bytes);
356 if (recv_bytes > recv_size)
357 recv_bytes = recv_size;
359 for (i = 0; i < recv_bytes; i += 4)
360 intel_dp_unpack_aux(intel_uncore_read(uncore, ch_data[i >> 2]),
361 recv + i, recv_bytes - i);
365 cpu_latency_qos_update_request(&intel_dp->pm_qos, PM_QOS_DEFAULT_VALUE);
368 intel_pps_vdd_off_unlocked(intel_dp, false);
370 intel_pps_unlock(intel_dp, pps_wakeref);
371 intel_display_power_put_async(i915, aux_domain, aux_wakeref);
374 intel_tc_port_unlock(dig_port);
379 #define BARE_ADDRESS_SIZE 3
380 #define HEADER_SIZE (BARE_ADDRESS_SIZE + 1)
383 intel_dp_aux_header(u8 txbuf[HEADER_SIZE],
384 const struct drm_dp_aux_msg *msg)
386 txbuf[0] = (msg->request << 4) | ((msg->address >> 16) & 0xf);
387 txbuf[1] = (msg->address >> 8) & 0xff;
388 txbuf[2] = msg->address & 0xff;
389 txbuf[3] = msg->size - 1;
392 static u32 intel_dp_aux_xfer_flags(const struct drm_dp_aux_msg *msg)
395 * If we're trying to send the HDCP Aksv, we need to set a the Aksv
396 * select bit to inform the hardware to send the Aksv after our header
397 * since we can't access that data from software.
399 if ((msg->request & ~DP_AUX_I2C_MOT) == DP_AUX_NATIVE_WRITE &&
400 msg->address == DP_AUX_HDCP_AKSV)
401 return DP_AUX_CH_CTL_AUX_AKSV_SELECT;
407 intel_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
409 struct intel_dp *intel_dp = container_of(aux, struct intel_dp, aux);
410 struct drm_i915_private *i915 = dp_to_i915(intel_dp);
411 u8 txbuf[20], rxbuf[20];
412 size_t txsize, rxsize;
413 u32 flags = intel_dp_aux_xfer_flags(msg);
416 intel_dp_aux_header(txbuf, msg);
418 switch (msg->request & ~DP_AUX_I2C_MOT) {
419 case DP_AUX_NATIVE_WRITE:
420 case DP_AUX_I2C_WRITE:
421 case DP_AUX_I2C_WRITE_STATUS_UPDATE:
422 txsize = msg->size ? HEADER_SIZE + msg->size : BARE_ADDRESS_SIZE;
423 rxsize = 2; /* 0 or 1 data bytes */
425 if (drm_WARN_ON(&i915->drm, txsize > 20))
428 drm_WARN_ON(&i915->drm, !msg->buffer != !msg->size);
431 memcpy(txbuf + HEADER_SIZE, msg->buffer, msg->size);
433 ret = intel_dp_aux_xfer(intel_dp, txbuf, txsize,
434 rxbuf, rxsize, flags);
436 msg->reply = rxbuf[0] >> 4;
439 /* Number of bytes written in a short write. */
440 ret = clamp_t(int, rxbuf[1], 0, msg->size);
442 /* Return payload size. */
448 case DP_AUX_NATIVE_READ:
449 case DP_AUX_I2C_READ:
450 txsize = msg->size ? HEADER_SIZE : BARE_ADDRESS_SIZE;
451 rxsize = msg->size + 1;
453 if (drm_WARN_ON(&i915->drm, rxsize > 20))
456 ret = intel_dp_aux_xfer(intel_dp, txbuf, txsize,
457 rxbuf, rxsize, flags);
459 msg->reply = rxbuf[0] >> 4;
461 * Assume happy day, and copy the data. The caller is
462 * expected to check msg->reply before touching it.
464 * Return payload size.
467 memcpy(msg->buffer, rxbuf + 1, ret);
479 static i915_reg_t g4x_aux_ctl_reg(struct intel_dp *intel_dp)
481 struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
482 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
483 enum aux_ch aux_ch = dig_port->aux_ch;
489 return DP_AUX_CH_CTL(aux_ch);
491 MISSING_CASE(aux_ch);
492 return DP_AUX_CH_CTL(AUX_CH_B);
496 static i915_reg_t g4x_aux_data_reg(struct intel_dp *intel_dp, int index)
498 struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
499 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
500 enum aux_ch aux_ch = dig_port->aux_ch;
506 return DP_AUX_CH_DATA(aux_ch, index);
508 MISSING_CASE(aux_ch);
509 return DP_AUX_CH_DATA(AUX_CH_B, index);
513 static i915_reg_t ilk_aux_ctl_reg(struct intel_dp *intel_dp)
515 struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
516 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
517 enum aux_ch aux_ch = dig_port->aux_ch;
521 return DP_AUX_CH_CTL(aux_ch);
525 return PCH_DP_AUX_CH_CTL(aux_ch);
527 MISSING_CASE(aux_ch);
528 return DP_AUX_CH_CTL(AUX_CH_A);
532 static i915_reg_t ilk_aux_data_reg(struct intel_dp *intel_dp, int index)
534 struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
535 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
536 enum aux_ch aux_ch = dig_port->aux_ch;
540 return DP_AUX_CH_DATA(aux_ch, index);
544 return PCH_DP_AUX_CH_DATA(aux_ch, index);
546 MISSING_CASE(aux_ch);
547 return DP_AUX_CH_DATA(AUX_CH_A, index);
551 static i915_reg_t skl_aux_ctl_reg(struct intel_dp *intel_dp)
553 struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
554 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
555 enum aux_ch aux_ch = dig_port->aux_ch;
564 return DP_AUX_CH_CTL(aux_ch);
566 MISSING_CASE(aux_ch);
567 return DP_AUX_CH_CTL(AUX_CH_A);
571 static i915_reg_t skl_aux_data_reg(struct intel_dp *intel_dp, int index)
573 struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
574 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
575 enum aux_ch aux_ch = dig_port->aux_ch;
584 return DP_AUX_CH_DATA(aux_ch, index);
586 MISSING_CASE(aux_ch);
587 return DP_AUX_CH_DATA(AUX_CH_A, index);
591 static i915_reg_t tgl_aux_ctl_reg(struct intel_dp *intel_dp)
593 struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
594 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
595 enum aux_ch aux_ch = dig_port->aux_ch;
605 case AUX_CH_USBC5: /* aka AUX_CH_D_XELPD */
606 case AUX_CH_USBC6: /* aka AUX_CH_E_XELPD */
607 return DP_AUX_CH_CTL(aux_ch);
609 MISSING_CASE(aux_ch);
610 return DP_AUX_CH_CTL(AUX_CH_A);
614 static i915_reg_t tgl_aux_data_reg(struct intel_dp *intel_dp, int index)
616 struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
617 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
618 enum aux_ch aux_ch = dig_port->aux_ch;
628 case AUX_CH_USBC5: /* aka AUX_CH_D_XELPD */
629 case AUX_CH_USBC6: /* aka AUX_CH_E_XELPD */
630 return DP_AUX_CH_DATA(aux_ch, index);
632 MISSING_CASE(aux_ch);
633 return DP_AUX_CH_DATA(AUX_CH_A, index);
637 void intel_dp_aux_fini(struct intel_dp *intel_dp)
639 if (cpu_latency_qos_request_active(&intel_dp->pm_qos))
640 cpu_latency_qos_remove_request(&intel_dp->pm_qos);
642 kfree(intel_dp->aux.name);
645 void intel_dp_aux_init(struct intel_dp *intel_dp)
647 struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
648 struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
649 struct intel_encoder *encoder = &dig_port->base;
650 enum aux_ch aux_ch = dig_port->aux_ch;
652 if (DISPLAY_VER(dev_priv) >= 12) {
653 intel_dp->aux_ch_ctl_reg = tgl_aux_ctl_reg;
654 intel_dp->aux_ch_data_reg = tgl_aux_data_reg;
655 } else if (DISPLAY_VER(dev_priv) >= 9) {
656 intel_dp->aux_ch_ctl_reg = skl_aux_ctl_reg;
657 intel_dp->aux_ch_data_reg = skl_aux_data_reg;
658 } else if (HAS_PCH_SPLIT(dev_priv)) {
659 intel_dp->aux_ch_ctl_reg = ilk_aux_ctl_reg;
660 intel_dp->aux_ch_data_reg = ilk_aux_data_reg;
662 intel_dp->aux_ch_ctl_reg = g4x_aux_ctl_reg;
663 intel_dp->aux_ch_data_reg = g4x_aux_data_reg;
666 if (DISPLAY_VER(dev_priv) >= 9)
667 intel_dp->get_aux_clock_divider = skl_get_aux_clock_divider;
668 else if (IS_BROADWELL(dev_priv) || IS_HASWELL(dev_priv))
669 intel_dp->get_aux_clock_divider = hsw_get_aux_clock_divider;
670 else if (HAS_PCH_SPLIT(dev_priv))
671 intel_dp->get_aux_clock_divider = ilk_get_aux_clock_divider;
673 intel_dp->get_aux_clock_divider = g4x_get_aux_clock_divider;
675 if (DISPLAY_VER(dev_priv) >= 9)
676 intel_dp->get_aux_send_ctl = skl_get_aux_send_ctl;
678 intel_dp->get_aux_send_ctl = g4x_get_aux_send_ctl;
680 intel_dp->aux.drm_dev = &dev_priv->drm;
681 drm_dp_aux_init(&intel_dp->aux);
683 /* Failure to allocate our preferred name is not critical */
684 if (DISPLAY_VER(dev_priv) >= 13 && aux_ch >= AUX_CH_D_XELPD)
685 intel_dp->aux.name = kasprintf(GFP_KERNEL, "AUX %c/%s",
686 aux_ch_name(aux_ch - AUX_CH_D_XELPD + AUX_CH_D),
688 else if (DISPLAY_VER(dev_priv) >= 12 && aux_ch >= AUX_CH_USBC1)
689 intel_dp->aux.name = kasprintf(GFP_KERNEL, "AUX USBC%c/%s",
690 aux_ch - AUX_CH_USBC1 + '1',
693 intel_dp->aux.name = kasprintf(GFP_KERNEL, "AUX %c/%s",
697 intel_dp->aux.transfer = intel_dp_aux_transfer;
698 cpu_latency_qos_add_request(&intel_dp->pm_qos, PM_QOS_DEFAULT_VALUE);