Re: [Intel-gfx] [PATCH v2] drm/i915/dsi: Use unconditional msleep() instead of intel_dsi_msleep()

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Tue, Apr 25, 2023 at 09:44:41PM +0200, Hans de Goede wrote:
> The intel_dsi_msleep() helper skips sleeping if the MIPI-sequences have
> a version of 3 or newer and the panel is in vid-mode.
> 
> This is based on the big comment around line 730 which starts with
> "Panel enable/disable sequences from the VBT spec.", where
> the "v3 video mode seq" column does not have any wait t# entries.
> 
> Checking the Windows driver shows that it does always honor
> the VBT delays independent of the version of the VBT sequences.
> 
> Commit 6fdb335f1c9c ("drm/i915/dsi: Use unconditional msleep for
> the panel_on_delay when there is no reset-deassert MIPI-sequence")
> switched to a direct msleep() instead of intel_dsi_msleep()
> when there is no MIPI_SEQ_DEASSERT_RESET sequence, to fix
> the panel on an Acer Aspire Switch 10 E SW3-016 not turning on.
> 
> And now testing on a Nextbook Ares 8A shows that panel_on_delay
> must always be honored otherwise the panel will not turn on.
> 
> Instead of only always using regular msleep() for panel_on_delay
> do as Windows does and always use regular msleep() everywhere
> were intel_dsi_msleep() is used and drop the intel_dsi_msleep()
> helper.
> 
> Changes in v2:
> - Replace all intel_dsi_msleep() calls instead of just
>   the intel_dsi_msleep(panel_on_delay) call
> 
> Fixes: 6fdb335f1c9c ("drm/i915/dsi: Use unconditional msleep for the panel_on_delay when there is no reset-deassert MIPI-sequence")
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>

Thanks. Added cc:stable and pushed to drm-intel-next.

> ---
>  drivers/gpu/drm/i915/display/icl_dsi.c       |  2 +-
>  drivers/gpu/drm/i915/display/intel_dsi_vbt.c | 11 ----------
>  drivers/gpu/drm/i915/display/intel_dsi_vbt.h |  1 -
>  drivers/gpu/drm/i915/display/vlv_dsi.c       | 22 +++++---------------
>  4 files changed, 6 insertions(+), 30 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/icl_dsi.c b/drivers/gpu/drm/i915/display/icl_dsi.c
> index fc0eaf40dc94..6dd942522021 100644
> --- a/drivers/gpu/drm/i915/display/icl_dsi.c
> +++ b/drivers/gpu/drm/i915/display/icl_dsi.c
> @@ -1211,7 +1211,7 @@ static void gen11_dsi_powerup_panel(struct intel_encoder *encoder)
>  
>  	/* panel power on related mipi dsi vbt sequences */
>  	intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_POWER_ON);
> -	intel_dsi_msleep(intel_dsi, intel_dsi->panel_on_delay);
> +	msleep(intel_dsi->panel_on_delay);
>  	intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_DEASSERT_RESET);
>  	intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_INIT_OTP);
>  	intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_DISPLAY_ON);
> diff --git a/drivers/gpu/drm/i915/display/intel_dsi_vbt.c b/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
> index 2cbc1292ab38..f102c13cb959 100644
> --- a/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
> +++ b/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
> @@ -762,17 +762,6 @@ void intel_dsi_vbt_exec_sequence(struct intel_dsi *intel_dsi,
>  		gpiod_set_value_cansleep(intel_dsi->gpio_backlight, 0);
>  }
>  
> -void intel_dsi_msleep(struct intel_dsi *intel_dsi, int msec)
> -{
> -	struct intel_connector *connector = intel_dsi->attached_connector;
> -
> -	/* For v3 VBTs in vid-mode the delays are part of the VBT sequences */
> -	if (is_vid_mode(intel_dsi) && connector->panel.vbt.dsi.seq_version >= 3)
> -		return;
> -
> -	msleep(msec);
> -}
> -
>  void intel_dsi_log_params(struct intel_dsi *intel_dsi)
>  {
>  	struct drm_i915_private *i915 = to_i915(intel_dsi->base.base.dev);
> diff --git a/drivers/gpu/drm/i915/display/intel_dsi_vbt.h b/drivers/gpu/drm/i915/display/intel_dsi_vbt.h
> index dc642c1fe7ef..468d873fab1a 100644
> --- a/drivers/gpu/drm/i915/display/intel_dsi_vbt.h
> +++ b/drivers/gpu/drm/i915/display/intel_dsi_vbt.h
> @@ -16,7 +16,6 @@ void intel_dsi_vbt_gpio_init(struct intel_dsi *intel_dsi, bool panel_is_on);
>  void intel_dsi_vbt_gpio_cleanup(struct intel_dsi *intel_dsi);
>  void intel_dsi_vbt_exec_sequence(struct intel_dsi *intel_dsi,
>  				 enum mipi_seq seq_id);
> -void intel_dsi_msleep(struct intel_dsi *intel_dsi, int msec);
>  void intel_dsi_log_params(struct intel_dsi *intel_dsi);
>  
>  #endif /* __INTEL_DSI_VBT_H__ */
> diff --git a/drivers/gpu/drm/i915/display/vlv_dsi.c b/drivers/gpu/drm/i915/display/vlv_dsi.c
> index 2289f6b1b4eb..37efeab52581 100644
> --- a/drivers/gpu/drm/i915/display/vlv_dsi.c
> +++ b/drivers/gpu/drm/i915/display/vlv_dsi.c
> @@ -783,7 +783,6 @@ static void intel_dsi_pre_enable(struct intel_atomic_state *state,
>  {
>  	struct intel_dsi *intel_dsi = enc_to_intel_dsi(encoder);
>  	struct intel_crtc *crtc = to_intel_crtc(pipe_config->uapi.crtc);
> -	struct intel_connector *connector = to_intel_connector(conn_state->connector);
>  	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
>  	enum pipe pipe = crtc->pipe;
>  	enum port port;
> @@ -831,21 +830,10 @@ static void intel_dsi_pre_enable(struct intel_atomic_state *state,
>  	if (!IS_GEMINILAKE(dev_priv))
>  		intel_dsi_prepare(encoder, pipe_config);
>  
> +	/* Give the panel time to power-on and then deassert its reset */
>  	intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_POWER_ON);
> -
> -	/*
> -	 * Give the panel time to power-on and then deassert its reset.
> -	 * Depending on the VBT MIPI sequences version the deassert-seq
> -	 * may contain the necessary delay, intel_dsi_msleep() will skip
> -	 * the delay in that case. If there is no deassert-seq, then an
> -	 * unconditional msleep is used to give the panel time to power-on.
> -	 */
> -	if (connector->panel.vbt.dsi.sequence[MIPI_SEQ_DEASSERT_RESET]) {
> -		intel_dsi_msleep(intel_dsi, intel_dsi->panel_on_delay);
> -		intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_DEASSERT_RESET);
> -	} else {
> -		msleep(intel_dsi->panel_on_delay);
> -	}
> +	msleep(intel_dsi->panel_on_delay);
> +	intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_DEASSERT_RESET);
>  
>  	if (IS_GEMINILAKE(dev_priv)) {
>  		glk_cold_boot = glk_dsi_enable_io(encoder);
> @@ -879,7 +867,7 @@ static void intel_dsi_pre_enable(struct intel_atomic_state *state,
>  		msleep(20); /* XXX */
>  		for_each_dsi_port(port, intel_dsi->ports)
>  			dpi_send_cmd(intel_dsi, TURN_ON, false, port);
> -		intel_dsi_msleep(intel_dsi, 100);
> +		msleep(100);
>  
>  		intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_DISPLAY_ON);
>  
> @@ -1007,7 +995,7 @@ static void intel_dsi_post_disable(struct intel_atomic_state *state,
>  	/* Assert reset */
>  	intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_ASSERT_RESET);
>  
> -	intel_dsi_msleep(intel_dsi, intel_dsi->panel_off_delay);
> +	msleep(intel_dsi->panel_off_delay);
>  	intel_dsi_vbt_exec_sequence(intel_dsi, MIPI_SEQ_POWER_OFF);
>  
>  	intel_dsi->panel_power_off_time = ktime_get_boottime();
> -- 
> 2.39.1

-- 
Ville Syrjälä
Intel