drm/vc4: hdmi: Rename pixel_rate variable

The pixel_rate field in the vc4_hdmi_connector_state struct actually
stores the TMDS character rate, let's rename it for consistency.

Suggested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Acked-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220222164042.403112-2-maxime@cerno.tech

drm/vc4: hdmi: Add a spinlock to protect register access

The vc4 HDMI driver has multiple path shared between the CEC, ALSA and
KMS frameworks, plus two interrupt handlers (CEC and hotplug) that will
read and modify a number of registers.

Even though not bug has been reported so far, it's definitely unsafe, so
let's just add a spinlock to protect the register access of the HDMI
controller.

Link: https://lore.kernel.org/r/20211025141113.702757-5-maxime@cerno.tech
Fixes: c8b75bca92cb ("drm/vc4: Add KMS support for Raspberry Pi.")
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>

drm/vc4: hdmi: Use the connector state pixel rate for the PHY

The PHY initialisation parameters are not based on the pixel clock but
the TMDS clock rate which can be the pixel clock in the standard case,
but could be adjusted based on some parameters like the bits per color.

Since the TMDS clock rate is stored in our custom connector state
already, let's reuse it from there instead of computing it again.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20201215154243.540115-8-maxime@cerno.tech

drm/vc4: hdmi: Support the BCM2711 HDMI controllers

Now that the driver is ready for it, let's bring in the HDMI controllers
variants for the BCM2711.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Tested-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Link: https://patchwork.freedesktop.org/patch/msgid/b540c7a9ebb7ad51da39271a8388b69c7e27e582.1599120059.git-series.maxime@cerno.tech

drm/vc4: hdmi: Add PHY RNG enable / disable function

Let's continue the implementation of hooks for the parts that change in the
BCM2711 SoC with the PHY RNG setup.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Tested-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Link: https://patchwork.freedesktop.org/patch/msgid/216155f1c0b83e622ac60a2f7d00eb707de3acba.1599120059.git-series.maxime@cerno.tech

drm/vc4: hdmi: Add PHY init and disable function

The HDMI PHY in the BCM2711 HDMI controller is significantly more
complicated to setup than in the older BCM283x SoCs.

Let's add hooks to enable and disable the PHY.

Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Tested-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Link: https://patchwork.freedesktop.org/patch/msgid/7216826284dbc60a58bdacd662805d20699e5c80.1599120059.git-series.maxime@cerno.tech