[PATCH RFC v2 1/8] drm/bridge: dw-hdmi: Add SCDC and TMDS Scrambling support
Andrzej Hajda
a.hajda at samsung.com
Tue Dec 18 12:25:10 UTC 2018
Hi Neil,
On 30.11.2018 14:42, Neil Armstrong wrote:
> Add support for SCDC Setup for TMDS Clock > 3.4GHz and enable TMDS
> Scrambling when supported or mandatory.
>
> This patch also adds an helper to setup the control bit to support
> the high TMDS Bit Period/TMDS Clock-Period Ratio as required with
> TMDS Clock > 3.4GHz for HDMI2.0 3840x2160 at 60/50 modes.
>
> These changes were based on work done by Huicong Xu <xhc at rock-chips.com>
> and Nickey Yang <nickey.yang at rock-chips.com> to support HDMI2.0 modes
> on the Rockchip 4.4 BSP kernel at [1]
>
> [1] https://github.com/rockchip-linux/kernel/tree/release-4.4
>
> Cc: Nickey Yang <nickey.yang at rock-chips.com>
> Cc: Huicong Xu <xhc at rock-chips.com>
> Signed-off-by: Neil Armstrong <narmstrong at baylibre.com>
> ---
> drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 88 ++++++++++++++++++++++-
> drivers/gpu/drm/bridge/synopsys/dw-hdmi.h | 1 +
> include/drm/bridge/dw_hdmi.h | 1 +
> 3 files changed, 87 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> index 64c3cf027518..fcd941d52753 100644
> --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> @@ -28,6 +28,7 @@
> #include <drm/drm_crtc_helper.h>
> #include <drm/drm_edid.h>
> #include <drm/drm_encoder_slave.h>
> +#include <drm/drm_scdc_helper.h>
> #include <drm/bridge/dw_hdmi.h>
>
> #include <uapi/linux/media-bus-format.h>
> @@ -43,6 +44,11 @@
>
> #define HDMI_EDID_LEN 512
>
> +/* DW-HDMI Controller >= 0x200a are at least compliant with SCDC version 1 */
> +#define SCDC_MIN_SOURCE_VERSION 0x1
> +
> +#define HDMI14_MAX_TMDSCLK 340000000
> +
> enum hdmi_datamap {
> RGB444_8B = 0x01,
> RGB444_10B = 0x03,
> @@ -1015,6 +1021,33 @@ void dw_hdmi_phy_i2c_write(struct dw_hdmi *hdmi, unsigned short data,
> }
> EXPORT_SYMBOL_GPL(dw_hdmi_phy_i2c_write);
>
> +/*
> + * HDMI2.0 Specifies the following procedure for High TMDS Bit Rates:
> + * - The Source shall suspend transmission of the TMDS clock and data
> + * - The Source shall write to the TMDS_Bit_Clock_Ratio bit to change it
> + * from a 0 to a 1 or from a 1 to a 0
> + * - The Source shall allow a minimum of 1 ms and a maximum of 100 ms from
> + * the time the TMDS_Bit_Clock_Ratio bit is written until resuming
> + * transmission of TMDS clock and data
> + *
> + * To respect the 100ms maximum delay, the dw_hdmi_set_high_tmds_clock_ratio()
> + * helper should called right before enabling the TMDS Clock and Data in
> + * the PHY configuration callback.
> + */
> +void dw_hdmi_set_high_tmds_clock_ratio(struct dw_hdmi *hdmi)
> +{
> + unsigned long mtmdsclock = hdmi->hdmi_data.video_mode.mpixelclock;
> +
> + /* Control for TMDS Bit Period/TMDS Clock-Period Ratio */
> + if (hdmi->connector.display_info.hdmi.scdc.supported) {
> + if (mtmdsclock > HDMI14_MAX_TMDSCLK)
> + drm_scdc_set_high_tmds_clock_ratio(hdmi->ddc, 1);
> + else
> + drm_scdc_set_high_tmds_clock_ratio(hdmi->ddc, 0);
> + }
> +}
> +EXPORT_SYMBOL_GPL(dw_hdmi_set_high_tmds_clock_ratio);
> +
> static void dw_hdmi_phy_enable_powerdown(struct dw_hdmi *hdmi, bool enable)
> {
> hdmi_mask_writeb(hdmi, !enable, HDMI_PHY_CONF0,
> @@ -1216,6 +1249,8 @@ static int hdmi_phy_configure(struct dw_hdmi *hdmi)
>
> dw_hdmi_phy_power_off(hdmi);
>
> + dw_hdmi_set_high_tmds_clock_ratio(hdmi);
> +
> /* Leave low power consumption mode by asserting SVSRET. */
> if (phy->has_svsret)
> dw_hdmi_phy_enable_svsret(hdmi, 1);
> @@ -1237,6 +1272,10 @@ static int hdmi_phy_configure(struct dw_hdmi *hdmi)
> return ret;
> }
>
> + /* Wait for resuming transmission of TMDS clock and data */
> + if (mpixelclock > HDMI14_MAX_TMDSCLK)
> + msleep(100);
> +
> return dw_hdmi_phy_power_on(hdmi);
> }
>
> @@ -1340,11 +1379,12 @@ static void hdmi_tx_hdcp_config(struct dw_hdmi *hdmi)
>
> static void hdmi_config_AVI(struct dw_hdmi *hdmi, struct drm_display_mode *mode)
> {
> + bool is_hdmi2_sink = hdmi->connector.display_info.hdmi.scdc.supported;
> struct hdmi_avi_infoframe frame;
> u8 val;
>
> /* Initialise info frame from DRM mode */
> - drm_hdmi_avi_infoframe_from_display_mode(&frame, mode, false);
> + drm_hdmi_avi_infoframe_from_display_mode(&frame, mode, is_hdmi2_sink);
>
> if (hdmi_bus_fmt_is_yuv444(hdmi->hdmi_data.enc_out_bus_format))
> frame.colorspace = HDMI_COLORSPACE_YUV444;
> @@ -1503,7 +1543,8 @@ static void hdmi_config_vendor_specific_infoframe(struct dw_hdmi *hdmi,
> static void hdmi_av_composer(struct dw_hdmi *hdmi,
> const struct drm_display_mode *mode)
> {
> - u8 inv_val;
> + u8 inv_val, bytes;
> + struct drm_hdmi_info *hdmi_info = &hdmi->connector.display_info.hdmi;
> struct hdmi_vmode *vmode = &hdmi->hdmi_data.video_mode;
> int hblank, vblank, h_de_hs, v_de_vs, hsync_len, vsync_len;
> unsigned int vdisplay;
> @@ -1513,7 +1554,9 @@ static void hdmi_av_composer(struct dw_hdmi *hdmi,
> dev_dbg(hdmi->dev, "final pixclk = %d\n", vmode->mpixelclock);
>
> /* Set up HDMI_FC_INVIDCONF */
> - inv_val = (hdmi->hdmi_data.hdcp_enable ?
> + inv_val = (hdmi->hdmi_data.hdcp_enable ||
> + vmode->mpixelclock > HDMI14_MAX_TMDSCLK ||
> + hdmi_info->scdc.scrambling.low_rates ?
> HDMI_FC_INVIDCONF_HDCP_KEEPOUT_ACTIVE :
> HDMI_FC_INVIDCONF_HDCP_KEEPOUT_INACTIVE);
>
> @@ -1562,6 +1605,45 @@ static void hdmi_av_composer(struct dw_hdmi *hdmi,
> vsync_len /= 2;
> }
>
> + /* Scrambling Control */
> + if (hdmi_info->scdc.supported) {
> + if (vmode->mpixelclock > HDMI14_MAX_TMDSCLK ||
> + hdmi_info->scdc.scrambling.low_rates) {
> + /*
> + * HDMI2.0 Specifies the following procedure:
> + * After the Source Device has determined that
> + * SCDC_Present is set (=1), the Source Device should
> + * write the accurate Version of the Source Device
> + * to the Source Version field in the SCDCS.
> + * Source Devices compliant shall set the
> + * Source Version = 1.
> + */
> + drm_scdc_readb(&hdmi->i2c->adap, SCDC_SINK_VERSION,
> + &bytes);
> + drm_scdc_writeb(&hdmi->i2c->adap, SCDC_SOURCE_VERSION,
> + min_t(u8, bytes, SCDC_MIN_SOURCE_VERSION));
> +
> + /* Enabled Scrambling in the Sink */
> + drm_scdc_set_scrambling(&hdmi->i2c->adap, 1);
> +
> + /*
> + * To activate the scrambler feature, you must ensure
> + * that the quasi-static configuration bit
> + * fc_invidconf.HDCP_keepout is set at configuration
> + * time, before the required mc_swrstzreq.tmdsswrst_req
> + * reset request is issued.
> + */
> + hdmi_writeb(hdmi, (u8)~HDMI_MC_SWRSTZ_TMDSSWRST_REQ,
Are you sure you need casting to u8?
> + HDMI_MC_SWRSTZ);
> + hdmi_writeb(hdmi, 1, HDMI_FC_SCRAMBLER_CTRL);
> + } else {
> + hdmi_writeb(hdmi, 0, HDMI_FC_SCRAMBLER_CTRL);
> + hdmi_writeb(hdmi, (u8)~HDMI_MC_SWRSTZ_TMDSSWRST_REQ,
> + HDMI_MC_SWRSTZ);
> + drm_scdc_set_scrambling(&hdmi->i2c->adap, 0);
> + }
> + }
> +
> /* Set up horizontal active pixel width */
> hdmi_writeb(hdmi, mode->hdisplay >> 8, HDMI_FC_INHACTV1);
> hdmi_writeb(hdmi, mode->hdisplay, HDMI_FC_INHACTV0);
> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.h b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.h
> index 9d90eb9c46e5..3f3c616eba97 100644
> --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.h
> +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.h
> @@ -255,6 +255,7 @@
> #define HDMI_FC_MASK2 0x10DA
> #define HDMI_FC_POL2 0x10DB
> #define HDMI_FC_PRCONF 0x10E0
> +#define HDMI_FC_SCRAMBLER_CTRL 0x10E1
>
> #define HDMI_FC_GMD_STAT 0x1100
> #define HDMI_FC_GMD_EN 0x1101
> diff --git a/include/drm/bridge/dw_hdmi.h b/include/drm/bridge/dw_hdmi.h
> index 9c56412bb2cf..7a02744ce0bc 100644
> --- a/include/drm/bridge/dw_hdmi.h
> +++ b/include/drm/bridge/dw_hdmi.h
> @@ -157,6 +157,7 @@ void dw_hdmi_setup_rx_sense(struct dw_hdmi *hdmi, bool hpd, bool rx_sense);
> void dw_hdmi_set_sample_rate(struct dw_hdmi *hdmi, unsigned int rate);
> void dw_hdmi_audio_enable(struct dw_hdmi *hdmi);
> void dw_hdmi_audio_disable(struct dw_hdmi *hdmi);
> +void dw_hdmi_set_high_tmds_clock_ratio(struct dw_hdmi *hdmi);
>
> /* PHY configuration */
> void dw_hdmi_phy_i2c_set_addr(struct dw_hdmi *hdmi, u8 address);
Reviewed-by: Andrzej Hajda <a.hajda at samsung.com>
--
Regards
Andrzej
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