Re: [RFC PATCH 3/3] drm: bridge: samsung-dsim: Remove init quirk for Exynos
On 18.04.23 15:12, Marek Szyprowski wrote: > On 18.04.2023 12:42, Frieder Schrempf wrote: >> From: Frieder Schrempf >> >> Assuming that with the init flow fixed to meet the documentation at >> [1] and the pre_enable_prev_first flag set in downstream bridge/panel >> drivers which require it, we can use the default flow for Exynos as >> already done for i.MX8M. >> >> [1] >> https://docs.kernel.org/gpu/drm-kms-helpers.html#mipi-dsi-bridge-operation >> >> Signed-off-by: Frieder Schrempf >> --- >> I have no idea if my assumptions are correct and if this works at all. >> There's a very good chance it doesn't... > > Unfortunately this change breaks all Exynos boards with DSI panels. I've > check all 4 panels that are in mainline and none worked. Ok, thanks for testing anyway! As already mentioned this was rather a shot in the dark, as I didn't even bother trying to fully understand what's going on on the Exynos side. For now I will just remove this patch from the series in the next iteration.
Re: [RFC PATCH 3/3] drm: bridge: samsung-dsim: Remove init quirk for Exynos
On 18.04.2023 12:42, Frieder Schrempf wrote:
> From: Frieder Schrempf
>
> Assuming that with the init flow fixed to meet the documentation at
> [1] and the pre_enable_prev_first flag set in downstream bridge/panel
> drivers which require it, we can use the default flow for Exynos as
> already done for i.MX8M.
>
> [1] https://docs.kernel.org/gpu/drm-kms-helpers.html#mipi-dsi-bridge-operation
>
> Signed-off-by: Frieder Schrempf
> ---
> I have no idea if my assumptions are correct and if this works at all.
> There's a very good chance it doesn't...
Unfortunately this change breaks all Exynos boards with DSI panels. I've
check all 4 panels that are in mainline and none worked.
> ---
> drivers/gpu/drm/bridge/samsung-dsim.c | 39 ---
> 1 file changed, 11 insertions(+), 28 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/samsung-dsim.c
> b/drivers/gpu/drm/bridge/samsung-dsim.c
> index 9775779721d9..8c68b767ae50 100644
> --- a/drivers/gpu/drm/bridge/samsung-dsim.c
> +++ b/drivers/gpu/drm/bridge/samsung-dsim.c
> @@ -1336,18 +1336,12 @@ static void samsung_dsim_atomic_pre_enable(struct
> drm_bridge *bridge,
>
> dsi->state |= DSIM_STATE_ENABLED;
>
> - /*
> - * For Exynos-DSIM the downstream bridge, or panel are expecting
> - * the host initialization during DSI transfer.
> - */
> - if (!samsung_dsim_hw_is_exynos(dsi->plat_data->hw_type)) {
> - ret = samsung_dsim_init(dsi);
> - if (ret)
> - return;
> + ret = samsung_dsim_init(dsi);
> + if (ret)
> + return;
>
> - samsung_dsim_set_display_mode(dsi);
> - samsung_dsim_set_display_enable(dsi, true);
> - }
> + samsung_dsim_set_display_mode(dsi);
> + samsung_dsim_set_display_enable(dsi, true);
> }
>
> static void samsung_dsim_atomic_enable(struct drm_bridge *bridge,
> @@ -1356,14 +1350,9 @@ static void samsung_dsim_atomic_enable(struct
> drm_bridge *bridge,
> struct samsung_dsim *dsi = bridge_to_dsi(bridge);
> u32 reg;
>
> - if (samsung_dsim_hw_is_exynos(dsi->plat_data->hw_type)) {
> - samsung_dsim_set_display_mode(dsi);
> - samsung_dsim_set_display_enable(dsi, true);
> - } else {
> - reg = samsung_dsim_read(dsi, DSIM_ESCMODE_REG);
> - reg &= ~DSIM_FORCE_STOP_STATE;
> - samsung_dsim_write(dsi, DSIM_ESCMODE_REG, reg);
> - }
> + reg = samsung_dsim_read(dsi, DSIM_ESCMODE_REG);
> + reg &= ~DSIM_FORCE_STOP_STATE;
> + samsung_dsim_write(dsi, DSIM_ESCMODE_REG, reg);
>
> dsi->state |= DSIM_STATE_VIDOUT_AVAILABLE;
> }
> @@ -1377,11 +1366,9 @@ static void samsung_dsim_atomic_disable(struct
> drm_bridge *bridge,
> if (!(dsi->state & DSIM_STATE_ENABLED))
> return;
>
> - if (!samsung_dsim_hw_is_exynos(dsi->plat_data->hw_type)) {
> - reg = samsung_dsim_read(dsi, DSIM_ESCMODE_REG);
> - reg |= DSIM_FORCE_STOP_STATE;
> - samsung_dsim_write(dsi, DSIM_ESCMODE_REG, reg);
> - }
> + reg = samsung_dsim_read(dsi, DSIM_ESCMODE_REG);
> + reg |= DSIM_FORCE_STOP_STATE;
> + samsung_dsim_write(dsi, DSIM_ESCMODE_REG, reg);
>
> dsi->state &= ~DSIM_STATE_VIDOUT_AVAILABLE;
> }
> @@ -1680,10 +1667,6 @@ static ssize_t samsung_dsim_host_transfer(struct
> mipi_dsi_host *host,
> if (!(dsi->state & DSIM_STATE_ENABLED))
> return -EINVAL;
>
> - ret = samsung_dsim_init(dsi);
> - if (ret)
> - return ret;
> -
> ret = mipi_dsi_create_packet(, msg);
> if (ret < 0)
> return ret;
Best regards
--
Marek Szyprowski, PhD
Samsung R Institute Poland
[RFC PATCH 3/3] drm: bridge: samsung-dsim: Remove init quirk for Exynos
From: Frieder Schrempf
Assuming that with the init flow fixed to meet the documentation at
[1] and the pre_enable_prev_first flag set in downstream bridge/panel
drivers which require it, we can use the default flow for Exynos as
already done for i.MX8M.
[1] https://docs.kernel.org/gpu/drm-kms-helpers.html#mipi-dsi-bridge-operation
Signed-off-by: Frieder Schrempf
---
I have no idea if my assumptions are correct and if this works at all.
There's a very good chance it doesn't...
---
drivers/gpu/drm/bridge/samsung-dsim.c | 39 ---
1 file changed, 11 insertions(+), 28 deletions(-)
diff --git a/drivers/gpu/drm/bridge/samsung-dsim.c
b/drivers/gpu/drm/bridge/samsung-dsim.c
index 9775779721d9..8c68b767ae50 100644
--- a/drivers/gpu/drm/bridge/samsung-dsim.c
+++ b/drivers/gpu/drm/bridge/samsung-dsim.c
@@ -1336,18 +1336,12 @@ static void samsung_dsim_atomic_pre_enable(struct
drm_bridge *bridge,
dsi->state |= DSIM_STATE_ENABLED;
- /*
-* For Exynos-DSIM the downstream bridge, or panel are expecting
-* the host initialization during DSI transfer.
-*/
- if (!samsung_dsim_hw_is_exynos(dsi->plat_data->hw_type)) {
- ret = samsung_dsim_init(dsi);
- if (ret)
- return;
+ ret = samsung_dsim_init(dsi);
+ if (ret)
+ return;
- samsung_dsim_set_display_mode(dsi);
- samsung_dsim_set_display_enable(dsi, true);
- }
+ samsung_dsim_set_display_mode(dsi);
+ samsung_dsim_set_display_enable(dsi, true);
}
static void samsung_dsim_atomic_enable(struct drm_bridge *bridge,
@@ -1356,14 +1350,9 @@ static void samsung_dsim_atomic_enable(struct drm_bridge
*bridge,
struct samsung_dsim *dsi = bridge_to_dsi(bridge);
u32 reg;
- if (samsung_dsim_hw_is_exynos(dsi->plat_data->hw_type)) {
- samsung_dsim_set_display_mode(dsi);
- samsung_dsim_set_display_enable(dsi, true);
- } else {
- reg = samsung_dsim_read(dsi, DSIM_ESCMODE_REG);
- reg &= ~DSIM_FORCE_STOP_STATE;
- samsung_dsim_write(dsi, DSIM_ESCMODE_REG, reg);
- }
+ reg = samsung_dsim_read(dsi, DSIM_ESCMODE_REG);
+ reg &= ~DSIM_FORCE_STOP_STATE;
+ samsung_dsim_write(dsi, DSIM_ESCMODE_REG, reg);
dsi->state |= DSIM_STATE_VIDOUT_AVAILABLE;
}
@@ -1377,11 +1366,9 @@ static void samsung_dsim_atomic_disable(struct
drm_bridge *bridge,
if (!(dsi->state & DSIM_STATE_ENABLED))
return;
- if (!samsung_dsim_hw_is_exynos(dsi->plat_data->hw_type)) {
- reg = samsung_dsim_read(dsi, DSIM_ESCMODE_REG);
- reg |= DSIM_FORCE_STOP_STATE;
- samsung_dsim_write(dsi, DSIM_ESCMODE_REG, reg);
- }
+ reg = samsung_dsim_read(dsi, DSIM_ESCMODE_REG);
+ reg |= DSIM_FORCE_STOP_STATE;
+ samsung_dsim_write(dsi, DSIM_ESCMODE_REG, reg);
dsi->state &= ~DSIM_STATE_VIDOUT_AVAILABLE;
}
@@ -1680,10 +1667,6 @@ static ssize_t samsung_dsim_host_transfer(struct
mipi_dsi_host *host,
if (!(dsi->state & DSIM_STATE_ENABLED))
return -EINVAL;
- ret = samsung_dsim_init(dsi);
- if (ret)
- return ret;
-
ret = mipi_dsi_create_packet(, msg);
if (ret < 0)
return ret;
--
2.40.0
