Re: [PATCH v2 3/4] drm/sun4i: tcon: Support the LVDS Dual-Link on the A20
Hi Maxime,
Thank you for the patch.
On Thu, Jul 30, 2020 at 11:35:03AM +0200, Maxime Ripard wrote:
> The A20 can use its second TCON as the secondary LVDS link in a dual-link
> setup, with the TCON0 being the main link. Extend a bit the parsing code to
> leverage the DRM dual-link code, register only the LVDS output on the
> primary TCON, and add the needed bits to setup the TCON properly.
>
> Signed-off-by: Maxime Ripard
> ---
> drivers/gpu/drm/sun4i/sun4i_tcon.c | 36 +++-
> drivers/gpu/drm/sun4i/sun4i_tcon.h | 4 +++-
> 2 files changed, 40 insertions(+)
>
> diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c
> b/drivers/gpu/drm/sun4i/sun4i_tcon.c
> index d03ad75f9900..ed2abf6eb18b 100644
> --- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
> +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
> @@ -487,6 +487,9 @@ static void sun4i_tcon0_mode_set_lvds(struct sun4i_tcon
> *tcon,
> else
> reg |= SUN4I_TCON0_LVDS_IF_DATA_POL_NORMAL;
>
> + if (tcon->lvds_dual_link)
> + reg |= SUN4I_TCON0_LVDS_IF_DUAL_LINK;
> +
> if (sun4i_tcon_get_pixel_depth(encoder) == 24)
> reg |= SUN4I_TCON0_LVDS_IF_BITWIDTH_24BITS;
> else
> @@ -896,6 +899,16 @@ static int sun4i_tcon_register_panel(struct drm_device
> *drm,
> return sun4i_rgb_init(drm, tcon);
>
> /*
> + * Only the TCON0 will be relevant for the LVDS output, so if
> + * our ID is something else, let's prevent our TCON from
> + * registering its own LVDS output
> + */
> + if (tcon->id) {
> + dev_info(dev, "Secondary TCON, disabling panel output");
This may worry the user unnecessarily. I'd make it a debug message, or
drop it completely, and like reword it a bit as pointed out by Chen-Yu.
> + return 0;
> + }
> +
> + /*
>* This can only be made optional since we've had DT
>* nodes without the LVDS reset properties.
>*
> @@ -941,6 +954,28 @@ static int sun4i_tcon_register_panel(struct drm_device
> *drm,
> return -ENODEV;
> }
>
> + /*
> + * If we don't have a second TCON, we will never be able to do
> + * dual-link LVDS, so we don't have much more to do.
> + */
> + companion = of_parse_phandle(dev->of_node, "allwinner,lvds-companion",
> 0);
Should there be a patch to add this property to the DT bindings ?
> + if (!companion)
> + return 0;
> +
> + /*
> + * Let's do a sanity check on the dual-link setup to make sure
> + * everything is properly described.
> + */
> + ret = drm_of_lvds_get_dual_link_pixel_order(dev->of_node, 1, 0,
> + companion, 1, 0);
> + if (ret < 0) {
> + dev_err(dev, "Invalid Dual-Link Configuration.\n");
> + return ret;
> + }
> +
> + dev_info(dev, "Primary TCON, enabling LVDS Dual-Link");
> + tcon->lvds_dual_link = true;
> +
> return sun4i_lvds_init(drm, tcon);
> }
>
> @@ -1500,6 +1535,7 @@ static const struct sun4i_tcon_quirks
> sun7i_a20_tcon0_quirks = {
> };
>
> static const struct sun4i_tcon_quirks sun7i_a20_quirks = {
> + .supports_lvds = true,
Should this be split to a separate patch, or at least mentioned in the
commit message ?
> .has_channel_0 = true,
> .has_channel_1 = true,
> .dclk_min_div = 4,
> diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.h
> b/drivers/gpu/drm/sun4i/sun4i_tcon.h
> index cfbf4e6c1679..51c4e09cdd13 100644
> --- a/drivers/gpu/drm/sun4i/sun4i_tcon.h
> +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.h
> @@ -98,6 +98,7 @@
>
> #define SUN4I_TCON0_LVDS_IF_REG 0x84
> #define SUN4I_TCON0_LVDS_IF_EN BIT(31)
> +#define SUN4I_TCON0_LVDS_IF_DUAL_LINKBIT(30)
> #define SUN4I_TCON0_LVDS_IF_BITWIDTH_MASKBIT(26)
> #define SUN4I_TCON0_LVDS_IF_BITWIDTH_18BITS (1 << 26)
> #define SUN4I_TCON0_LVDS_IF_BITWIDTH_24BITS (0 << 26)
> @@ -274,6 +275,9 @@ struct sun4i_tcon {
> /* Associated crtc */
> struct sun4i_crtc *crtc;
>
> + /* Is the LVDS link a dual-channel link? */
> + boollvds_dual_link;
> +
> int id;
>
> /* TCON list management */
--
Regards,
Laurent Pinchart
___
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel
Re: [PATCH v2 3/4] drm/sun4i: tcon: Support the LVDS Dual-Link on the A20
On Thu, Jul 30, 2020 at 5:35 PM Maxime Ripard wrote:
>
> The A20 can use its second TCON as the secondary LVDS link in a dual-link
> setup, with the TCON0 being the main link. Extend a bit the parsing code to
> leverage the DRM dual-link code, register only the LVDS output on the
> primary TCON, and add the needed bits to setup the TCON properly.
>
> Signed-off-by: Maxime Ripard
> ---
> drivers/gpu/drm/sun4i/sun4i_tcon.c | 36 +++-
> drivers/gpu/drm/sun4i/sun4i_tcon.h | 4 +++-
> 2 files changed, 40 insertions(+)
>
> diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c
> b/drivers/gpu/drm/sun4i/sun4i_tcon.c
> index d03ad75f9900..ed2abf6eb18b 100644
> --- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
> +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
> @@ -487,6 +487,9 @@ static void sun4i_tcon0_mode_set_lvds(struct sun4i_tcon
> *tcon,
> else
> reg |= SUN4I_TCON0_LVDS_IF_DATA_POL_NORMAL;
>
> + if (tcon->lvds_dual_link)
> + reg |= SUN4I_TCON0_LVDS_IF_DUAL_LINK;
> +
> if (sun4i_tcon_get_pixel_depth(encoder) == 24)
> reg |= SUN4I_TCON0_LVDS_IF_BITWIDTH_24BITS;
> else
> @@ -896,6 +899,16 @@ static int sun4i_tcon_register_panel(struct drm_device
> *drm,
> return sun4i_rgb_init(drm, tcon);
>
> /*
> +* Only the TCON0 will be relevant for the LVDS output, so if
> +* our ID is something else, let's prevent our TCON from
> +* registering its own LVDS output
> +*/
> + if (tcon->id) {
> + dev_info(dev, "Secondary TCON, disabling panel output");
Nit: "disabling" is a bit misleading.
Just stating that it is used as a secondary link
> + return 0;
> + }
> +
> + /*
> * This can only be made optional since we've had DT
> * nodes without the LVDS reset properties.
> *
> @@ -941,6 +954,28 @@ static int sun4i_tcon_register_panel(struct drm_device
> *drm,
> return -ENODEV;
> }
>
> + /*
> +* If we don't have a second TCON, we will never be able to do
> +* dual-link LVDS, so we don't have much more to do.
> +*/
> + companion = of_parse_phandle(dev->of_node,
> "allwinner,lvds-companion", 0);
> + if (!companion)
> + return 0;
I assume you want
return sun4i_lvds_init(drm, tcon);
otherwise single-link LVDS would not work anymore?
ChenYu
> +
> + /*
> +* Let's do a sanity check on the dual-link setup to make sure
> +* everything is properly described.
> +*/
> + ret = drm_of_lvds_get_dual_link_pixel_order(dev->of_node, 1, 0,
> + companion, 1, 0);
> + if (ret < 0) {
> + dev_err(dev, "Invalid Dual-Link Configuration.\n");
> + return ret;
> + }
> +
> + dev_info(dev, "Primary TCON, enabling LVDS Dual-Link");
> + tcon->lvds_dual_link = true;
> +
> return sun4i_lvds_init(drm, tcon);
> }
>
> @@ -1500,6 +1535,7 @@ static const struct sun4i_tcon_quirks
> sun7i_a20_tcon0_quirks = {
> };
>
> static const struct sun4i_tcon_quirks sun7i_a20_quirks = {
> + .supports_lvds = true,
> .has_channel_0 = true,
> .has_channel_1 = true,
> .dclk_min_div = 4,
> diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.h
> b/drivers/gpu/drm/sun4i/sun4i_tcon.h
> index cfbf4e6c1679..51c4e09cdd13 100644
> --- a/drivers/gpu/drm/sun4i/sun4i_tcon.h
> +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.h
> @@ -98,6 +98,7 @@
>
> #define SUN4I_TCON0_LVDS_IF_REG0x84
> #define SUN4I_TCON0_LVDS_IF_EN BIT(31)
> +#define SUN4I_TCON0_LVDS_IF_DUAL_LINK BIT(30)
> #define SUN4I_TCON0_LVDS_IF_BITWIDTH_MASK BIT(26)
> #define SUN4I_TCON0_LVDS_IF_BITWIDTH_18BITS(1 << 26)
> #define SUN4I_TCON0_LVDS_IF_BITWIDTH_24BITS(0 << 26)
> @@ -274,6 +275,9 @@ struct sun4i_tcon {
> /* Associated crtc */
> struct sun4i_crtc *crtc;
>
> + /* Is the LVDS link a dual-channel link? */
> + boollvds_dual_link;
> +
> int id;
>
> /* TCON list management */
> --
> git-series 0.9.1
___
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel
[PATCH v2 3/4] drm/sun4i: tcon: Support the LVDS Dual-Link on the A20
The A20 can use its second TCON as the secondary LVDS link in a dual-link
setup, with the TCON0 being the main link. Extend a bit the parsing code to
leverage the DRM dual-link code, register only the LVDS output on the
primary TCON, and add the needed bits to setup the TCON properly.
Signed-off-by: Maxime Ripard
---
drivers/gpu/drm/sun4i/sun4i_tcon.c | 36 +++-
drivers/gpu/drm/sun4i/sun4i_tcon.h | 4 +++-
2 files changed, 40 insertions(+)
diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c
b/drivers/gpu/drm/sun4i/sun4i_tcon.c
index d03ad75f9900..ed2abf6eb18b 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
@@ -487,6 +487,9 @@ static void sun4i_tcon0_mode_set_lvds(struct sun4i_tcon
*tcon,
else
reg |= SUN4I_TCON0_LVDS_IF_DATA_POL_NORMAL;
+ if (tcon->lvds_dual_link)
+ reg |= SUN4I_TCON0_LVDS_IF_DUAL_LINK;
+
if (sun4i_tcon_get_pixel_depth(encoder) == 24)
reg |= SUN4I_TCON0_LVDS_IF_BITWIDTH_24BITS;
else
@@ -896,6 +899,16 @@ static int sun4i_tcon_register_panel(struct drm_device
*drm,
return sun4i_rgb_init(drm, tcon);
/*
+* Only the TCON0 will be relevant for the LVDS output, so if
+* our ID is something else, let's prevent our TCON from
+* registering its own LVDS output
+*/
+ if (tcon->id) {
+ dev_info(dev, "Secondary TCON, disabling panel output");
+ return 0;
+ }
+
+ /*
* This can only be made optional since we've had DT
* nodes without the LVDS reset properties.
*
@@ -941,6 +954,28 @@ static int sun4i_tcon_register_panel(struct drm_device
*drm,
return -ENODEV;
}
+ /*
+* If we don't have a second TCON, we will never be able to do
+* dual-link LVDS, so we don't have much more to do.
+*/
+ companion = of_parse_phandle(dev->of_node, "allwinner,lvds-companion",
0);
+ if (!companion)
+ return 0;
+
+ /*
+* Let's do a sanity check on the dual-link setup to make sure
+* everything is properly described.
+*/
+ ret = drm_of_lvds_get_dual_link_pixel_order(dev->of_node, 1, 0,
+ companion, 1, 0);
+ if (ret < 0) {
+ dev_err(dev, "Invalid Dual-Link Configuration.\n");
+ return ret;
+ }
+
+ dev_info(dev, "Primary TCON, enabling LVDS Dual-Link");
+ tcon->lvds_dual_link = true;
+
return sun4i_lvds_init(drm, tcon);
}
@@ -1500,6 +1535,7 @@ static const struct sun4i_tcon_quirks
sun7i_a20_tcon0_quirks = {
};
static const struct sun4i_tcon_quirks sun7i_a20_quirks = {
+ .supports_lvds = true,
.has_channel_0 = true,
.has_channel_1 = true,
.dclk_min_div = 4,
diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.h
b/drivers/gpu/drm/sun4i/sun4i_tcon.h
index cfbf4e6c1679..51c4e09cdd13 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.h
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.h
@@ -98,6 +98,7 @@
#define SUN4I_TCON0_LVDS_IF_REG0x84
#define SUN4I_TCON0_LVDS_IF_EN BIT(31)
+#define SUN4I_TCON0_LVDS_IF_DUAL_LINK BIT(30)
#define SUN4I_TCON0_LVDS_IF_BITWIDTH_MASK BIT(26)
#define SUN4I_TCON0_LVDS_IF_BITWIDTH_18BITS(1 << 26)
#define SUN4I_TCON0_LVDS_IF_BITWIDTH_24BITS(0 << 26)
@@ -274,6 +275,9 @@ struct sun4i_tcon {
/* Associated crtc */
struct sun4i_crtc *crtc;
+ /* Is the LVDS link a dual-channel link? */
+ boollvds_dual_link;
+
int id;
/* TCON list management */
--
git-series 0.9.1
___
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel
