[PATCH 1/3] drm/stm: dsi: move lane capability detection in probe()

[PATCH 1/3] drm/stm: dsi: move lane capability detection in probe()

[Antonio Borneo]

There is no need to re-compute the dsi lane capability because it
only depends on dsi hw version.
Since dsi hw version is detected at probe(), move there also the
assignment of dsi lane capability.

Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
---
To: David Airlie <airlied@linux.ie>
To: Daniel Vetter <daniel@ffwll.ch>
To: Andrzej Hajda <a.hajda@samsung.com>
To: Neil Armstrong <narmstrong@baylibre.com>
To: Robert Foss <robert.foss@linaro.org>
To: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
To: Jonas Karlman <jonas@kwiboo.se>
To: Jernej Skrabec <jernej.skrabec@gmail.com>
To: Yannick Fertre <yannick.fertre@foss.st.com>
To: Philippe Cornu <philippe.cornu@foss.st.com>
To: Benjamin Gaignard <benjamin.gaignard@linaro.org>
To: Maxime Coquelin <mcoquelin.stm32@gmail.com>
To: Alexandre Torgue <alexandre.torgue@foss.st.com>
To: Philipp Zabel <p.zabel@pengutronix.de>
To: dri-devel@lists.freedesktop.org
To: linux-stm32@st-md-mailman.stormreply.com
To: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
---
 drivers/gpu/drm/stm/dw_mipi_dsi-stm.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
index 32cb41b2202f..480fdf256f01 100644
--- a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
+++ b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
@@ -247,14 +247,6 @@ dw_mipi_dsi_get_lane_mbps(void *priv_data, const struct drm_display_mode *mode,
 	int ret, bpp;
 	u32 val;
 
-	/* Update lane capabilities according to hw version */
-	dsi->lane_min_kbps = LANE_MIN_KBPS;
-	dsi->lane_max_kbps = LANE_MAX_KBPS;
-	if (dsi->hw_version == HWVER_131) {
-		dsi->lane_min_kbps *= 2;
-		dsi->lane_max_kbps *= 2;
-	}
-
 	pll_in_khz = (unsigned int)(clk_get_rate(dsi->pllref_clk) / 1000);
 
 	/* Compute requested pll out */
@@ -417,6 +409,14 @@ static int dw_mipi_dsi_stm_probe(struct platform_device *pdev)
 		goto err_dsi_probe;
 	}
 
+	/* set lane capabilities according to hw version */
+	dsi->lane_min_kbps = LANE_MIN_KBPS;
+	dsi->lane_max_kbps = LANE_MAX_KBPS;
+	if (dsi->hw_version == HWVER_131) {
+		dsi->lane_min_kbps *= 2;
+		dsi->lane_max_kbps *= 2;
+	}
+
 	dw_mipi_dsi_stm_plat_data.base = dsi->base;
 	dw_mipi_dsi_stm_plat_data.priv_data = dsi;
 

base-commit: 70704fbf67ddc07ffc81073a3af1f7b2171697eb
-- 
2.34.1

[PATCH 2/3] drm/bridge/synopsys: dsi: extend the prototype of mode_valid()

[Antonio Borneo]

To evaluate the validity of a video mode, some additional internal
value has to be passed to the platform implementation.

Extend the prototype of mode_valid().

Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
---
To: David Airlie <airlied@linux.ie>
To: Daniel Vetter <daniel@ffwll.ch>
To: Andrzej Hajda <a.hajda@samsung.com>
To: Neil Armstrong <narmstrong@baylibre.com>
To: Robert Foss <robert.foss@linaro.org>
To: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
To: Jonas Karlman <jonas@kwiboo.se>
To: Jernej Skrabec <jernej.skrabec@gmail.com>
To: Yannick Fertre <yannick.fertre@foss.st.com>
To: Philippe Cornu <philippe.cornu@foss.st.com>
To: Benjamin Gaignard <benjamin.gaignard@linaro.org>
To: Maxime Coquelin <mcoquelin.stm32@gmail.com>
To: Alexandre Torgue <alexandre.torgue@foss.st.com>
To: Philipp Zabel <p.zabel@pengutronix.de>
To: dri-devel@lists.freedesktop.org
To: linux-stm32@st-md-mailman.stormreply.com
To: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
---
 drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 5 ++++-
 include/drm/bridge/dw_mipi_dsi.h              | 4 +++-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
index e44e18a0112a..3f6564762e24 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
@@ -998,7 +998,10 @@ dw_mipi_dsi_bridge_mode_valid(struct drm_bridge *bridge,
 	enum drm_mode_status mode_status = MODE_OK;
 
 	if (pdata->mode_valid)
-		mode_status = pdata->mode_valid(pdata->priv_data, mode);
+		mode_status = pdata->mode_valid(pdata->priv_data, mode,
+						dsi->mode_flags,
+						dw_mipi_dsi_get_lanes(dsi),
+						dsi->format);
 
 	return mode_status;
 }
diff --git a/include/drm/bridge/dw_mipi_dsi.h b/include/drm/bridge/dw_mipi_dsi.h
index bda8aa7c2280..5286a53a1875 100644
--- a/include/drm/bridge/dw_mipi_dsi.h
+++ b/include/drm/bridge/dw_mipi_dsi.h
@@ -51,7 +51,9 @@ struct dw_mipi_dsi_plat_data {
 	unsigned int max_data_lanes;
 
 	enum drm_mode_status (*mode_valid)(void *priv_data,
-					   const struct drm_display_mode *mode);
+					   const struct drm_display_mode *mode,
+					   unsigned long mode_flags,
+					   u32 lanes, u32 format);
 
 	const struct dw_mipi_dsi_phy_ops *phy_ops;
 	const struct dw_mipi_dsi_host_ops *host_ops;
-- 
2.34.1

[PATCH 3/3] drm/stm: dsi: provide the implementation of mode_valid()

[Antonio Borneo]

The dsi has several constraints on the video modes it can support,
mainly due to the frequencies that can be generated by the PLL
integrated in the DSI device.

Verify that the required HS clock can be generated by the PLL.

The dsi clock from the dsi PLL and the ltdc pixel clock are
asynchronous. The dsi needs to return in LP mode during HFP or HBP
to re-synchronize at each video line.

Verify that the duration of HFP and HBP allows the dsi to enter in
LP mode.

Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
---
To: David Airlie <airlied@linux.ie>
To: Daniel Vetter <daniel@ffwll.ch>
To: Andrzej Hajda <a.hajda@samsung.com>
To: Neil Armstrong <narmstrong@baylibre.com>
To: Robert Foss <robert.foss@linaro.org>
To: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
To: Jonas Karlman <jonas@kwiboo.se>
To: Jernej Skrabec <jernej.skrabec@gmail.com>
To: Yannick Fertre <yannick.fertre@foss.st.com>
To: Philippe Cornu <philippe.cornu@foss.st.com>
To: Benjamin Gaignard <benjamin.gaignard@linaro.org>
To: Maxime Coquelin <mcoquelin.stm32@gmail.com>
To: Alexandre Torgue <alexandre.torgue@foss.st.com>
To: Philipp Zabel <p.zabel@pengutronix.de>
To: dri-devel@lists.freedesktop.org
To: linux-stm32@st-md-mailman.stormreply.com
To: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
---
 drivers/gpu/drm/stm/dw_mipi_dsi-stm.c | 98 +++++++++++++++++++++++++++
 1 file changed, 98 insertions(+)

diff --git a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
index 480fdf256f01..89897d5f5c72 100644
--- a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
+++ b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
@@ -322,6 +322,103 @@ dw_mipi_dsi_phy_get_timing(void *priv_data, unsigned int lane_mbps,
 	return 0;
 }
 
+#define CLK_TOLERANCE_HZ 50
+
+static enum drm_mode_status
+dw_mipi_dsi_stm_mode_valid(void *priv_data,
+			   const struct drm_display_mode *mode,
+			   unsigned long mode_flags, u32 lanes, u32 format)
+{
+	struct dw_mipi_dsi_stm *dsi = priv_data;
+	unsigned int idf, ndiv, odf, pll_in_khz, pll_out_khz;
+	int ret, bpp;
+
+	bpp = mipi_dsi_pixel_format_to_bpp(format);
+	if (bpp < 0)
+		return MODE_BAD;
+
+	/* Compute requested pll out */
+	pll_out_khz = mode->clock * bpp / lanes;
+
+	if (pll_out_khz > dsi->lane_max_kbps)
+		return MODE_CLOCK_HIGH;
+
+	if (mode_flags & MIPI_DSI_MODE_VIDEO_BURST) {
+		/* Add 20% to pll out to be higher than pixel bw */
+		pll_out_khz = (pll_out_khz * 12) / 10;
+	} else {
+		if (pll_out_khz < dsi->lane_min_kbps)
+			return MODE_CLOCK_LOW;
+	}
+
+	/* Compute best pll parameters */
+	idf = 0;
+	ndiv = 0;
+	odf = 0;
+	pll_in_khz = clk_get_rate(dsi->pllref_clk) / 1000;
+	ret = dsi_pll_get_params(dsi, pll_in_khz, pll_out_khz, &idf, &ndiv, &odf);
+	if (ret) {
+		DRM_WARN("Warning dsi_pll_get_params(): bad params\n");
+		return MODE_ERROR;
+	}
+
+	if (!(mode_flags & MIPI_DSI_MODE_VIDEO_BURST)) {
+		unsigned int px_clock_hz, target_px_clock_hz, lane_mbps;
+		int dsi_short_packet_size_px, hfp, hsync, hbp, delay_to_lp;
+		struct dw_mipi_dsi_dphy_timing dphy_timing;
+
+		/* Get the adjusted pll out value */
+		pll_out_khz = dsi_pll_get_clkout_khz(pll_in_khz, idf, ndiv, odf);
+
+		px_clock_hz = DIV_ROUND_CLOSEST_ULL(1000ULL * pll_out_khz * lanes, bpp);
+		target_px_clock_hz = mode->clock * 1000;
+		/*
+		 * Filter modes according to the clock value, particularly useful for
+		 * hdmi modes that require precise pixel clocks.
+		 */
+		if (px_clock_hz < target_px_clock_hz - CLK_TOLERANCE_HZ ||
+		    px_clock_hz > target_px_clock_hz + CLK_TOLERANCE_HZ)
+			return MODE_CLOCK_RANGE;
+
+		/* sync packets are codes as DSI short packets (4 bytes) */
+		dsi_short_packet_size_px = DIV_ROUND_UP(4 * BITS_PER_BYTE, bpp);
+
+		hfp = mode->hsync_start - mode->hdisplay;
+		hsync = mode->hsync_end - mode->hsync_start;
+		hbp = mode->htotal - mode->hsync_end;
+
+		/* hsync must be longer than 4 bytes HSS packets */
+		if (hsync < dsi_short_packet_size_px)
+			return MODE_HSYNC_NARROW;
+
+		if (mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) {
+			/* HBP must be longer than 4 bytes HSE packets */
+			if (hbp < dsi_short_packet_size_px)
+				return MODE_HSYNC_NARROW;
+			hbp -= dsi_short_packet_size_px;
+		} else {
+			/* With sync events HBP extends in the hsync */
+			hbp += hsync - dsi_short_packet_size_px;
+		}
+
+		lane_mbps = pll_out_khz / 1000;
+		ret = dw_mipi_dsi_phy_get_timing(priv_data, lane_mbps, &dphy_timing);
+		if (ret)
+			return MODE_ERROR;
+		/*
+		 * In non-burst mode DSI has to enter in LP during HFP
+		 * (horizontal front porch) or HBP (horizontal back porch) to
+		 * resync with LTDC pixel clock.
+		 */
+		delay_to_lp = DIV_ROUND_UP((dphy_timing.data_hs2lp + dphy_timing.data_lp2hs) *
+					   lanes * BITS_PER_BYTE, bpp);
+		if (hfp < delay_to_lp && hbp < delay_to_lp)
+			return MODE_HSYNC;
+	}
+
+	return MODE_OK;
+}
+
 static const struct dw_mipi_dsi_phy_ops dw_mipi_dsi_stm_phy_ops = {
 	.init = dw_mipi_dsi_phy_init,
 	.power_on = dw_mipi_dsi_phy_power_on,
@@ -332,6 +429,7 @@ static const struct dw_mipi_dsi_phy_ops dw_mipi_dsi_stm_phy_ops = {
 
 static struct dw_mipi_dsi_plat_data dw_mipi_dsi_stm_plat_data = {
 	.max_data_lanes = 2,
+	.mode_valid = dw_mipi_dsi_stm_mode_valid,
 	.phy_ops = &dw_mipi_dsi_stm_phy_ops,
 };
 
-- 
2.34.1

Re: [PATCH 1/3] drm/stm: dsi: move lane capability detection in probe()

[Philippe CORNU]

On 12/18/21 10:50 PM, Antonio Borneo wrote:
> There is no need to re-compute the dsi lane capability because it
> only depends on dsi hw version.
> Since dsi hw version is detected at probe(), move there also the
> assignment of dsi lane capability.
> 
> Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
> ---
> To: David Airlie <airlied@linux.ie>
> To: Daniel Vetter <daniel@ffwll.ch>
> To: Andrzej Hajda <a.hajda@samsung.com>
> To: Neil Armstrong <narmstrong@baylibre.com>
> To: Robert Foss <robert.foss@linaro.org>
> To: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
> To: Jonas Karlman <jonas@kwiboo.se>
> To: Jernej Skrabec <jernej.skrabec@gmail.com>
> To: Yannick Fertre <yannick.fertre@foss.st.com>
> To: Philippe Cornu <philippe.cornu@foss.st.com>
> To: Benjamin Gaignard <benjamin.gaignard@linaro.org>
> To: Maxime Coquelin <mcoquelin.stm32@gmail.com>
> To: Alexandre Torgue <alexandre.torgue@foss.st.com>
> To: Philipp Zabel <p.zabel@pengutronix.de>
> To: dri-devel@lists.freedesktop.org
> To: linux-stm32@st-md-mailman.stormreply.com
> To: linux-arm-kernel@lists.infradead.org
> Cc: linux-kernel@vger.kernel.org
> ---
>   drivers/gpu/drm/stm/dw_mipi_dsi-stm.c | 16 ++++++++--------
>   1 file changed, 8 insertions(+), 8 deletions(-)
> 

Hi Antonio,
many thanks for your patch.
Acked-by: Philippe Cornu <philippe.cornu@foss.st.com>
Reviewed-by: Philippe Cornu <philippe.cornu@foss.st.com>
Philippe :-)

Re: [PATCH 2/3] drm/bridge/synopsys: dsi: extend the prototype of mode_valid()

[Philippe CORNU]

On 12/18/21 10:50 PM, Antonio Borneo wrote:
> To evaluate the validity of a video mode, some additional internal
> value has to be passed to the platform implementation.
> 
> Extend the prototype of mode_valid().
> 
> Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
> ---
> To: David Airlie <airlied@linux.ie>
> To: Daniel Vetter <daniel@ffwll.ch>
> To: Andrzej Hajda <a.hajda@samsung.com>
> To: Neil Armstrong <narmstrong@baylibre.com>
> To: Robert Foss <robert.foss@linaro.org>
> To: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
> To: Jonas Karlman <jonas@kwiboo.se>
> To: Jernej Skrabec <jernej.skrabec@gmail.com>
> To: Yannick Fertre <yannick.fertre@foss.st.com>
> To: Philippe Cornu <philippe.cornu@foss.st.com>
> To: Benjamin Gaignard <benjamin.gaignard@linaro.org>
> To: Maxime Coquelin <mcoquelin.stm32@gmail.com>
> To: Alexandre Torgue <alexandre.torgue@foss.st.com>
> To: Philipp Zabel <p.zabel@pengutronix.de>
> To: dri-devel@lists.freedesktop.org
> To: linux-stm32@st-md-mailman.stormreply.com
> To: linux-arm-kernel@lists.infradead.org
> Cc: linux-kernel@vger.kernel.org
> ---
>   drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 5 ++++-
>   include/drm/bridge/dw_mipi_dsi.h              | 4 +++-
>   2 files changed, 7 insertions(+), 2 deletions(-)
> 

Hi Antonio,
many thanks for your patch.
(I should have done like that from the beginning as validating a mode in 
dsi requires dsi related information...)
Reviewed-by: Philippe Cornu <philippe.cornu@foss.st.com>
Philippe :-)

Re: [PATCH 3/3] drm/stm: dsi: provide the implementation of mode_valid()

[Philippe CORNU]

On 12/18/21 10:50 PM, Antonio Borneo wrote:
> The dsi has several constraints on the video modes it can support,
> mainly due to the frequencies that can be generated by the PLL
> integrated in the DSI device.
> 
> Verify that the required HS clock can be generated by the PLL.
> 
> The dsi clock from the dsi PLL and the ltdc pixel clock are
> asynchronous. The dsi needs to return in LP mode during HFP or HBP
> to re-synchronize at each video line.
> 
> Verify that the duration of HFP and HBP allows the dsi to enter in
> LP mode.
> 
> Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
> ---
> To: David Airlie <airlied@linux.ie>
> To: Daniel Vetter <daniel@ffwll.ch>
> To: Andrzej Hajda <a.hajda@samsung.com>
> To: Neil Armstrong <narmstrong@baylibre.com>
> To: Robert Foss <robert.foss@linaro.org>
> To: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
> To: Jonas Karlman <jonas@kwiboo.se>
> To: Jernej Skrabec <jernej.skrabec@gmail.com>
> To: Yannick Fertre <yannick.fertre@foss.st.com>
> To: Philippe Cornu <philippe.cornu@foss.st.com>
> To: Benjamin Gaignard <benjamin.gaignard@linaro.org>
> To: Maxime Coquelin <mcoquelin.stm32@gmail.com>
> To: Alexandre Torgue <alexandre.torgue@foss.st.com>
> To: Philipp Zabel <p.zabel@pengutronix.de>
> To: dri-devel@lists.freedesktop.org
> To: linux-stm32@st-md-mailman.stormreply.com
> To: linux-arm-kernel@lists.infradead.org
> Cc: linux-kernel@vger.kernel.org
> ---
>   drivers/gpu/drm/stm/dw_mipi_dsi-stm.c | 98 +++++++++++++++++++++++++++
>   1 file changed, 98 insertions(+)

Hi Antonio,
many thanks for your patch.
Nice improvement for better filtering supported modes...
Acked-by: Philippe Cornu <philippe.cornu@foss.st.com>
Reviewed-by: Philippe Cornu <philippe.cornu@foss.st.com>
Philippe :-)

Re: [PATCH 1/3] drm/stm: dsi: move lane capability detection in probe()

[Robert Foss]

On Tue, 4 Jan 2022 at 11:47, Philippe CORNU <philippe.cornu@foss.st.com> wrote:
>
>
>
> On 12/18/21 10:50 PM, Antonio Borneo wrote:
> > There is no need to re-compute the dsi lane capability because it
> > only depends on dsi hw version.
> > Since dsi hw version is detected at probe(), move there also the
> > assignment of dsi lane capability.
> >
> > Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
> > ---
> > To: David Airlie <airlied@linux.ie>
> > To: Daniel Vetter <daniel@ffwll.ch>
> > To: Andrzej Hajda <a.hajda@samsung.com>
> > To: Neil Armstrong <narmstrong@baylibre.com>
> > To: Robert Foss <robert.foss@linaro.org>
> > To: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
> > To: Jonas Karlman <jonas@kwiboo.se>
> > To: Jernej Skrabec <jernej.skrabec@gmail.com>
> > To: Yannick Fertre <yannick.fertre@foss.st.com>
> > To: Philippe Cornu <philippe.cornu@foss.st.com>
> > To: Benjamin Gaignard <benjamin.gaignard@linaro.org>
> > To: Maxime Coquelin <mcoquelin.stm32@gmail.com>
> > To: Alexandre Torgue <alexandre.torgue@foss.st.com>
> > To: Philipp Zabel <p.zabel@pengutronix.de>
> > To: dri-devel@lists.freedesktop.org
> > To: linux-stm32@st-md-mailman.stormreply.com
> > To: linux-arm-kernel@lists.infradead.org
> > Cc: linux-kernel@vger.kernel.org
> > ---
> >   drivers/gpu/drm/stm/dw_mipi_dsi-stm.c | 16 ++++++++--------
> >   1 file changed, 8 insertions(+), 8 deletions(-)
> >
>
> Hi Antonio,
> many thanks for your patch.
> Acked-by: Philippe Cornu <philippe.cornu@foss.st.com>
> Reviewed-by: Philippe Cornu <philippe.cornu@foss.st.com>
> Philippe :-)

Thanks for the series and the Acks.

Applied series to drm-misc-next