On Wed, 2011-06-29 at 21:10 +0800, Wu Fengguang wrote:
> Update: according to the spec, limit max a/v latencies to 500ms and
> avoid overflowing the ELD field Aud_Synch_Delay[7:0].
>
> Thanks to Pierre for pointing this out!
>
> btw, the drm_edid_to_eld() function reuses some code from Ben Skeggs.
> Ben, please add your Signed-off-by if the patch looks OK to you :)
I thought some of it looked familiar :)
Looks good to me, and looks like i'll be able to use this in nouveau
too. Thank you!
Ben.
>
> Thanks,
> Fengguang
>
> ---
> Add ELD support for Eaglelake, IbexPeak/Ironlake and SandyBridge/CougarPoint.
>
> ELD (EDID-Like Data) describes to the HDMI/DP audio driver the audio
> capabilities of the plugged monitor. It's built and passed to audio
> driver in 2 steps:
>
> (1) at get_modes time, parse EDID and save ELD to drm_connector.eld[]
>
> (2) at mode_set time, write drm_connector.eld[] to the Transcoder's hw
> ELD buffer and set the ELD_valid bit to inform HDMI/DP audio driver
>
> ELD selection policy: it's possible for one encoder to be associated
> with multiple connectors (ie. monitors), in which case the first found
> ELD will be used. This policy may not be suitable for all users, but
> let's start it simple first.
>
> The impact of ELD selection policy: assume there are two monitors, one
> supports stereo playback and the other has 8-channel output; cloned
> display mode is used, so that the two monitors are associated with the
> same internal encoder. If only the stereo playback capability is reported,
> the user won't be able to start 8-channel playback; if the 8-channel ELD
> is reported, then user space applications may send 8-channel samples
> down, however the user may actually be listening to the 2-channel
> monitor and not connecting speakers to the 8-channel monitor. Overall,
> it's more safe to report maximum profiles to the user space, so that
> the user can at least be able to do 8-channel playback if he want to.
>
> This patch is tested OK on G45/HDMI and IbexPeak/HDMI. DisplayPort is
> tested on several IbexPeak and Sandybridge boxes, however not working,
> possibly due to hardware/monitor problems.
>
> One known problem is that the GEN6_AUD_CNTL_ST/DIP_Port_Select field
> is always 0 (reserved). Without knowing the port number, I worked it
> around by setting the ELD_valid bit for ALL the three ports.
>
> CC: Zhao Yakui <yakui.zhao at intel.com>
> CC: Wang Zhenyu <zhenyu.z.wang at intel.com>
> CC: Jeremy Bush <contractfrombelow at gmail.com>
> CC: Christopher White <c.white at pulseforce.com>
> CC: "Bossart, Pierre-louis" <pierre-louis.bossart at intel.com>
> Signed-off-by: Wu Fengguang <fengguang.wu at intel.com>
Signed-off-by: Ben Skeggs <bskeggs at redhat.com>
> ---
> drivers/gpu/drm/drm_edid.c | 171 +++++++++++++++++++++++++
> drivers/gpu/drm/i915/i915_drv.h | 2
> drivers/gpu/drm/i915/i915_reg.h | 20 ++
> drivers/gpu/drm/i915/intel_display.c | 119 +++++++++++++++++
> drivers/gpu/drm/i915/intel_dp.c | 2
> drivers/gpu/drm/i915/intel_drv.h | 3
> drivers/gpu/drm/i915/intel_hdmi.c | 2
> drivers/gpu/drm/i915/intel_modes.c | 2
> include/drm/drm_crtc.h | 10 +
> include/drm/drm_edid.h | 9 +
> 10 files changed, 340 insertions(+)
>
> --- sound-2.6.orig/drivers/gpu/drm/drm_edid.c 2011-06-29 13:18:31.000000000
> +0800
> +++ sound-2.6/drivers/gpu/drm/drm_edid.c 2011-06-29 20:52:39.000000000
> +0800
> @@ -1292,6 +1292,7 @@ add_detailed_modes(struct drm_connector
> #define HDMI_IDENTIFIER 0x000C03
> #define AUDIO_BLOCK 0x01
> #define VENDOR_BLOCK 0x03
> +#define SPEAKER_BLOCK 0x04
> #define EDID_BASIC_AUDIO (1 << 6)
>
> /**
> @@ -1320,6 +1321,176 @@ u8 *drm_find_cea_extension(struct edid *
> }
> EXPORT_SYMBOL(drm_find_cea_extension);
>
> +static void
> +parse_hdmi_vsdb(struct drm_connector *connector, uint8_t *db)
> +{
> + connector->eld[5] |= (db[6] >> 7) << 1; /* Supports_AI */
> +
> + connector->dvi_dual = db[6] & 1;
> + connector->max_tmds_clock = db[7] * 5;
> +
> + connector->latency_present[0] = db[8] >> 7;
> + connector->latency_present[1] = (db[8] >> 6) & 1;
> + connector->video_latency[0] = db[9];
> + connector->audio_latency[0] = db[10];
> + connector->video_latency[1] = db[11];
> + connector->audio_latency[1] = db[12];
> +
> + DRM_LOG_KMS("HDMI: DVI dual %d, "
> + "max TMDS clock %d, "
> + "latency present %d %d, "
> + "video latency %d %d, "
> + "audio latency %d %d\n",
> + connector->dvi_dual,
> + connector->max_tmds_clock,
> + (int) connector->latency_present[0],
> + (int) connector->latency_present[1],
> + connector->video_latency[0],
> + connector->video_latency[1],
> + connector->audio_latency[0],
> + connector->audio_latency[1]);
> +}
> +
> +static void
> +monitor_name(struct detailed_timing *t, void *data)
> +{
> + if (t->data.other_data.type == EDID_DETAIL_MONITOR_NAME)
> + *(u8 **)data = t->data.other_data.data.str.str;
> +}
> +
> +/**
> + * drm_edid_to_eld - build ELD from EDID
> + * @connector: connector corresponding to the HDMI/DP sink
> + * @edid: EDID to parse
> + *
> + * Fill the ELD (EDID-Like Data) buffer for passing to the audio driver.
> + * Some ELD fields are left to the graphics driver caller:
> + * - Conn_Type
> + * - HDCP
> + * - Port_ID
> + */
> +void drm_edid_to_eld(struct drm_connector *connector, struct edid *edid)
> +{
> + uint8_t *eld = connector->eld;
> + u8 *cea;
> + u8 *name;
> + u8 *db;
> + int sad_count = 0;
> + int mnl;
> + int dbl;
> +
> + memset(eld, 0, sizeof(connector->eld));
> +
> + cea = drm_find_cea_extension(edid);
> + if (!cea) {
> + DRM_DEBUG_KMS("ELD: no CEA Extension found\n");
> + return;
> + }
> +
> + name = NULL;
> + drm_for_each_detailed_block((u8 *)edid, monitor_name, &name);
> + for (mnl = 0; name && mnl < 13; mnl++) {
> + if (name[mnl] == 0x0a)
> + break;
> + eld[20 + mnl] = name[mnl];
> + }
> + eld[4] = (cea[1] << 5) | mnl;
> + DRM_DEBUG_KMS("ELD monitor %s\n", eld + 20);
> +
> + eld[0] = 2 << 3; /* ELD version: 2 */
> +
> + eld[16] = edid->mfg_id[0];
> + eld[17] = edid->mfg_id[1];
> + eld[18] = edid->prod_code[0];
> + eld[19] = edid->prod_code[1];
> +
> + for (db = cea + 4; db < cea + cea[2]; db += dbl + 1) {
> + dbl = db[0] & 0x1f;
> +
> + switch ((db[0] & 0xe0) >> 5) {
> + case AUDIO_BLOCK: /* Audio Data Block, contains SADs */
> + sad_count = dbl / 3;
> + memcpy(eld + 20 + mnl, &db[1], dbl);
> + break;
> + case SPEAKER_BLOCK: /* Speaker Allocation Data Block */
> + eld[7] = db[1];
> + break;
> + case VENDOR_BLOCK:
> + /* HDMI Vendor-Specific Data Block */
> + if (db[1] == 0x03 && db[2] == 0x0c && db[3] == 0)
> + parse_hdmi_vsdb(connector, db);
> + break;
> + default:
> + break;
> + }
> + }
> + eld[5] |= sad_count << 4;
> + eld[2] = (20 + mnl + sad_count * 3 + 3) / 4;
> +
> + DRM_DEBUG_KMS("ELD size %d, SAD count %d\n", (int)eld[2], sad_count);
> +}
> +EXPORT_SYMBOL(drm_edid_to_eld);
> +
> +/**
> + * drm_av_sync_delay - HDMI/DP sink audio-video sync delay in milli-seconds
> + * @connector: connector associated with the HDMI/DP sink
> + * @mode: the display mode
> + */
> +int drm_av_sync_delay(struct drm_connector *connector,
> + struct drm_display_mode *mode)
> +{
> + int i = !!(mode->flags & DRM_MODE_FLAG_INTERLACE);
> + int a, v;
> +
> + if (!connector->latency_present[0])
> + return 0;
> + if (!connector->latency_present[1])
> + i = 0;
> +
> + a = connector->audio_latency[i];
> + v = connector->video_latency[i];
> +
> + /*
> + * HDMI/DP sink doesn't support audio or video?
> + */
> + if (a == 255 || v == 255)
> + return 0;
> +
> + /*
> + * Convert raw edid values to milli-seconds.
> + * Treat unknown latency as 0ms.
> + */
> + if (a)
> + a = min(2 * (a - 1), 500);
> + if (v)
> + v = min(2 * (v - 1), 500);
> +
> + return max(v - a, 0);
> +}
> +EXPORT_SYMBOL(drm_av_sync_delay);
> +
> +/**
> + * drm_select_eld - select one ELD from multiple HDMI/DP sinks
> + * @encoder: the encoder just changed display mode
> + * @mode: the adjusted display mode
> + *
> + * It's possible for one encoder to be associated with multiple HDMI/DP
> sinks.
> + * The policy is now hard coded to simply use the first HDMI/DP sink's ELD.
> + */
> +struct drm_connector *drm_select_eld(struct drm_encoder *encoder,
> + struct drm_display_mode *mode)
> +{
> + struct drm_connector *connector;
> + struct drm_device *dev = encoder->dev;
> +
> + list_for_each_entry(connector, &dev->mode_config.connector_list, head)
> + if (connector->encoder == encoder)
> + return connector;
> +
> + return NULL;
> +}
> +EXPORT_SYMBOL(drm_select_eld);
> +
> /**
> * drm_detect_hdmi_monitor - detect whether monitor is hdmi.
> * @edid: monitor EDID information
> --- sound-2.6.orig/drivers/gpu/drm/i915/intel_hdmi.c 2011-06-29
> 13:18:31.000000000 +0800
> +++ sound-2.6/drivers/gpu/drm/i915/intel_hdmi.c 2011-06-29
> 13:19:35.000000000 +0800
> @@ -151,6 +151,8 @@ static void intel_hdmi_mode_set(struct d
> POSTING_READ(intel_hdmi->sdvox_reg);
>
> intel_hdmi_set_avi_infoframe(encoder);
> +
> + intel_write_eld(encoder, crtc, adjusted_mode);
> }
>
> static void intel_hdmi_dpms(struct drm_encoder *encoder, int mode)
> --- sound-2.6.orig/include/drm/drm_edid.h 2011-06-29 13:18:31.000000000
> +0800
> +++ sound-2.6/include/drm/drm_edid.h 2011-06-29 13:19:35.000000000 +0800
> @@ -230,4 +230,13 @@ struct edid {
>
> #define EDID_PRODUCT_ID(e) ((e)->prod_code[0] | ((e)->prod_code[1] << 8))
>
> +struct drm_encoder;
> +struct drm_connector;
> +struct drm_display_mode;
> +void drm_edid_to_eld(struct drm_connector *connector, struct edid *edid);
> +int drm_av_sync_delay(struct drm_connector *connector,
> + struct drm_display_mode *mode);
> +struct drm_connector *drm_select_eld(struct drm_encoder *encoder,
> + struct drm_display_mode *mode);
> +
> #endif /* __DRM_EDID_H__ */
> --- sound-2.6.orig/drivers/gpu/drm/i915/intel_display.c 2011-06-29
> 13:18:31.000000000 +0800
> +++ sound-2.6/drivers/gpu/drm/i915/intel_display.c 2011-06-29
> 14:05:05.000000000 +0800
> @@ -30,6 +30,7 @@
> #include <linux/kernel.h>
> #include <linux/slab.h>
> #include <linux/vgaarb.h>
> +#include <drm/drm_edid.h>
> #include "drmP.h"
> #include "intel_drv.h"
> #include "i915_drm.h"
> @@ -5297,6 +5298,121 @@ static int intel_crtc_mode_set(struct dr
> return ret;
> }
>
> +static void g4x_write_eld(struct drm_connector *connector,
> + struct drm_crtc *crtc)
> +{
> + struct drm_i915_private *dev_priv = connector->dev->dev_private;
> + uint8_t *eld = connector->eld;
> + uint32_t eldv;
> + uint32_t len;
> + uint32_t i;
> +
> + i = I915_READ(G4X_AUD_VID_DID);
> +
> + if (i == INTEL_AUDIO_DEVBLC || i == INTEL_AUDIO_DEVCL)
> + eldv = G4X_ELDV_DEVCL_DEVBLC;
> + else
> + eldv = G4X_ELDV_DEVCTG;
> +
> + i = I915_READ(G4X_AUD_CNTL_ST);
> + i &= ~(eldv | G4X_ELD_ADDR);
> + len = (i >> 9) & 0x1f; /* ELD buffer size */
> + I915_WRITE(G4X_AUD_CNTL_ST, i);
> +
> + if (!eld[0])
> + return;
> +
> + len = min_t(uint8_t, eld[2], len);
> + for (i = 0; i < len; i++)
> + I915_WRITE(G4X_HDMIW_HDMIEDID, *((uint32_t *)eld + i));
> +
> + i = I915_READ(G4X_AUD_CNTL_ST);
> + i |= eldv;
> + I915_WRITE(G4X_AUD_CNTL_ST, i);
> +}
> +
> +static void ironlake_write_eld(struct drm_connector *connector,
> + struct drm_crtc *crtc)
> +{
> + struct drm_i915_private *dev_priv = connector->dev->dev_private;
> + uint8_t *eld = connector->eld;
> + uint32_t eldv;
> + uint32_t i;
> + int len;
> + int hdmiw_hdmiedid;
> + int aud_cntl_st;
> +
> + i = to_intel_crtc(crtc)->pipe;
> + hdmiw_hdmiedid = GEN6_HDMIW_HDMIEDID_A + i * 0x100;
> + aud_cntl_st = GEN6_AUD_CNTL_ST_A + i * 0x100;
> +
> + DRM_DEBUG_DRIVER("ELD on pipe %c\n", pipe_name(i));
> +
> + i = I915_READ(aud_cntl_st);
> + i = (i >> 29) & 0x3; /* DIP_Port_Select, 0x1 = PortB */
> + if (!i) {
> + DRM_DEBUG_DRIVER("Audio directed to unknown port\n");
> + /* operate blindly on all ports */
> + eldv = GEN6_ELD_VALIDB;
> + eldv |= GEN6_ELD_VALIDB << 4;
> + eldv |= GEN6_ELD_VALIDB << 8;
> + } else {
> + DRM_DEBUG_DRIVER("ELD on port %c\n", 'A' + i);
> + eldv = GEN6_ELD_VALIDB << ((i - 1) * 4);
> + }
> +
> + i = I915_READ(GEN6_AUD_CNTL_ST2);
> + i &= ~eldv;
> + I915_WRITE(GEN6_AUD_CNTL_ST2, i);
> +
> + if (!eld[0])
> + return;
> +
> + if (intel_pipe_has_type(crtc, INTEL_OUTPUT_DISPLAYPORT)) {
> + DRM_DEBUG_DRIVER("ELD: DisplayPort detected\n");
> + eld[5] |= (1 << 2); /* Conn_Type, 0x1 = DisplayPort */
> + }
> +
> + i = I915_READ(aud_cntl_st);
> + i &= ~GEN6_ELD_ADDRESS;
> + I915_WRITE(aud_cntl_st, i);
> +
> + i = I915_READ(aud_cntl_st);
> + len = (i & GEN6_ELD_BUFFER_SIZE) >> 10;
> + len = min_t(uint8_t, eld[2], len);
> + DRM_DEBUG_DRIVER("ELD size %d\n", len);
> + for (i = 0; i < len; i++)
> + I915_WRITE(hdmiw_hdmiedid, *((uint32_t *)eld + i));
> +
> + i = I915_READ(GEN6_AUD_CNTL_ST2);
> + i |= eldv;
> + I915_WRITE(GEN6_AUD_CNTL_ST2, i);
> +}
> +
> +void intel_write_eld(struct drm_encoder *encoder,
> + struct drm_crtc *crtc,
> + struct drm_display_mode *mode)
> +{
> + struct drm_connector *connector;
> + struct drm_device *dev = encoder->dev;
> + struct drm_i915_private *dev_priv = dev->dev_private;
> +
> + connector = drm_select_eld(encoder, mode);
> + if (!connector)
> + return;
> +
> + DRM_DEBUG_DRIVER("ELD on [CONNECTOR:%d:%s], [ENCODER:%d:%s]\n",
> + connector->base.id,
> + drm_get_connector_name(connector),
> + connector->encoder->base.id,
> + drm_get_encoder_name(connector->encoder));
> +
> + connector->eld[6] = drm_av_sync_delay(connector, mode) / 2;
> +
> + if (dev_priv->display.write_eld)
> + dev_priv->display.write_eld(connector, crtc);
> +}
> +
> /** Loads the palette/gamma unit for the CRTC with the prepared values */
> void intel_crtc_load_lut(struct drm_crtc *crtc)
> {
> @@ -7636,6 +7752,7 @@ static void intel_init_display(struct dr
> }
> dev_priv->display.fdi_link_train =
> ironlake_fdi_link_train;
> dev_priv->display.init_clock_gating =
> ironlake_init_clock_gating;
> + dev_priv->display.write_eld = ironlake_write_eld;
> } else if (IS_GEN6(dev)) {
> if (SNB_READ_WM0_LATENCY()) {
> dev_priv->display.update_wm =
> sandybridge_update_wm;
> @@ -7646,6 +7763,7 @@ static void intel_init_display(struct dr
> }
> dev_priv->display.fdi_link_train = gen6_fdi_link_train;
> dev_priv->display.init_clock_gating =
> gen6_init_clock_gating;
> + dev_priv->display.write_eld = ironlake_write_eld;
> } else if (IS_IVYBRIDGE(dev)) {
> /* FIXME: detect B0+ stepping and use auto training */
> dev_priv->display.fdi_link_train =
> ivb_manual_fdi_link_train;
> @@ -7676,6 +7794,7 @@ static void intel_init_display(struct dr
> } else
> dev_priv->display.update_wm = pineview_update_wm;
> } else if (IS_G4X(dev)) {
> + dev_priv->display.write_eld = g4x_write_eld;
> dev_priv->display.update_wm = g4x_update_wm;
> dev_priv->display.init_clock_gating = g4x_init_clock_gating;
> } else if (IS_GEN4(dev)) {
> --- sound-2.6.orig/drivers/gpu/drm/i915/i915_reg.h 2011-06-29
> 13:18:31.000000000 +0800
> +++ sound-2.6/drivers/gpu/drm/i915/i915_reg.h 2011-06-29 13:19:35.000000000
> +0800
> @@ -3436,4 +3436,24 @@
> #define GEN6_PCODE_WRITE_MIN_FREQ_TABLE 0x9
> #define GEN6_PCODE_DATA 0x138128
>
> +#define G4X_AUD_VID_DID 0x62020
> +#define INTEL_AUDIO_DEVCL 0x808629FB
> +#define INTEL_AUDIO_DEVBLC 0x80862801
> +#define INTEL_AUDIO_DEVCTG 0x80862802
> +
> +#define G4X_AUD_CNTL_ST 0x620B4
> +#define G4X_ELDV_DEVCL_DEVBLC (1 << 13)
> +#define G4X_ELDV_DEVCTG (1 << 14)
> +#define G4X_ELD_ADDR (0xf << 5)
> +#define G4X_ELD_ACK (1 << 4)
> +#define G4X_HDMIW_HDMIEDID 0x6210C
> +#define GEN6_HDMIW_HDMIEDID_A 0xE2050
> +#define GEN6_AUD_CNTL_ST_A 0xE20B4
> +#define GEN6_ELD_BUFFER_SIZE (0x1f << 10)
> +#define GEN6_ELD_ADDRESS (0x1f << 5)
> +#define GEN6_ELD_ACK (1 << 4)
> +#define GEN6_AUD_CNTL_ST2 0xE20C0
> +#define GEN6_ELD_VALIDB (1 << 0)
> +#define GEN6_CP_READYB (1 << 1)
> +
> #endif /* _I915_REG_H_ */
> --- sound-2.6.orig/drivers/gpu/drm/i915/intel_drv.h 2011-06-29
> 13:18:31.000000000 +0800
> +++ sound-2.6/drivers/gpu/drm/i915/intel_drv.h 2011-06-29
> 13:19:35.000000000 +0800
> @@ -346,4 +346,7 @@ extern void intel_fb_output_poll_changed
> extern void intel_fb_restore_mode(struct drm_device *dev);
>
> extern void intel_init_clock_gating(struct drm_device *dev);
> +extern void intel_write_eld(struct drm_encoder *encoder,
> + struct drm_crtc *crtc,
> + struct drm_display_mode *mode);
> #endif /* __INTEL_DRV_H__ */
> --- sound-2.6.orig/drivers/gpu/drm/i915/intel_modes.c 2011-06-29
> 13:18:31.000000000 +0800
> +++ sound-2.6/drivers/gpu/drm/i915/intel_modes.c 2011-06-29
> 13:19:35.000000000 +0800
> @@ -26,6 +26,7 @@
> #include <linux/slab.h>
> #include <linux/i2c.h>
> #include <linux/fb.h>
> +#include <drm/drm_edid.h>
> #include "drmP.h"
> #include "intel_drv.h"
> #include "i915_drv.h"
> @@ -74,6 +75,7 @@ int intel_ddc_get_modes(struct drm_conne
> if (edid) {
> drm_mode_connector_update_edid_property(connector, edid);
> ret = drm_add_edid_modes(connector, edid);
> + drm_edid_to_eld(connector, edid);
> connector->display_info.raw_edid = NULL;
> kfree(edid);
> }
> --- sound-2.6.orig/include/drm/drm_crtc.h 2011-06-29 13:18:31.000000000
> +0800
> +++ sound-2.6/include/drm/drm_crtc.h 2011-06-29 13:19:35.000000000 +0800
> @@ -464,6 +464,8 @@ enum drm_connector_force {
> /* DACs should rarely do this without a lot of testing */
> #define DRM_CONNECTOR_POLL_DISCONNECT (1 << 2)
>
> +#define MAX_ELD_BYTES 128
> +
> /**
> * drm_connector - central DRM connector control structure
> * @crtc: CRTC this connector is currently connected to, NULL if none
> @@ -520,6 +522,14 @@ struct drm_connector {
> uint32_t encoder_ids[DRM_CONNECTOR_MAX_ENCODER];
> uint32_t force_encoder_id;
> struct drm_encoder *encoder; /* currently active encoder */
> +
> + /* EDID bits */
> + uint8_t eld[MAX_ELD_BYTES];
> + bool dvi_dual;
> + int max_tmds_clock; /* in MHz */
> + bool latency_present[2];
> + int video_latency[2]; /* [0]: progressive, [1]: interlaced */
> + int audio_latency[2];
> };
>
> /**
> --- sound-2.6.orig/drivers/gpu/drm/i915/intel_dp.c 2011-06-29
> 13:18:31.000000000 +0800
> +++ sound-2.6/drivers/gpu/drm/i915/intel_dp.c 2011-06-29 13:19:35.000000000
> +0800
> @@ -793,6 +793,8 @@ intel_dp_mode_set(struct drm_encoder *en
> else
> intel_dp->DP |= DP_PLL_FREQ_270MHZ;
> }
> +
> + intel_write_eld(encoder, crtc, adjusted_mode);
> }
>
> static void ironlake_edp_panel_vdd_on(struct intel_dp *intel_dp)
> --- sound-2.6.orig/drivers/gpu/drm/i915/i915_drv.h 2011-06-29
> 13:18:31.000000000 +0800
> +++ sound-2.6/drivers/gpu/drm/i915/i915_drv.h 2011-06-29 13:19:35.000000000
> +0800
> @@ -208,6 +208,8 @@ struct drm_i915_display_funcs {
> struct drm_display_mode *adjusted_mode,
> int x, int y,
> struct drm_framebuffer *old_fb);
> + void (*write_eld)(struct drm_connector *connector,
> + struct drm_crtc *crtc);
> void (*fdi_link_train)(struct drm_crtc *crtc);
> void (*init_clock_gating)(struct drm_device *dev);
> void (*init_pch_clock_gating)(struct drm_device *dev);
