Hi, Am Donnerstag, 13. Juli 2023, 00:34:47 CEST schrieb Tim Harvey: > On Wed, May 3, 2023 at 9:33 AM Frieder Schrempf <frieder@xxxxxxx> wrote: > > From: Frieder Schrempf <frieder.schrempf@xxxxxxxxxx> > > > > According to the documentation [1] the proper enable flow is: > > > > 1. Enable DSI link and keep data lanes in LP-11 (stop state) > > 2. Disable stop state to bring data lanes into HS mode > > > > Currently we do this all at once within enable(), which doesn't > > allow to meet the requirements of some downstream bridges. > > > > To fix this we now enable the DSI in pre_enable() and force it > > into stop state using the FORCE_STOP_STATE bit in the ESCMODE > > register until enable() is called where we reset the bit. > > > > We currently do this only for i.MX8M as Exynos uses a different > > init flow where samsung_dsim_init() is called from > > samsung_dsim_host_transfer(). > > > > [1] > > https://docs.kernel.org/gpu/drm-kms-helpers.html#mipi-dsi-bridge-operatio > > n > > > > Signed-off-by: Frieder Schrempf <frieder.schrempf@xxxxxxxxxx> > > --- > > Changes for v2: > > * Drop RFC > > --- > > > > drivers/gpu/drm/bridge/samsung-dsim.c | 25 +++++++++++++++++++++++-- > > 1 file changed, 23 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/gpu/drm/bridge/samsung-dsim.c > > b/drivers/gpu/drm/bridge/samsung-dsim.c index e0a402a85787..9775779721d9 > > 100644 > > --- a/drivers/gpu/drm/bridge/samsung-dsim.c > > +++ b/drivers/gpu/drm/bridge/samsung-dsim.c > > @@ -859,6 +859,10 @@ static int samsung_dsim_init_link(struct samsung_dsim > > *dsi)> > > reg = samsung_dsim_read(dsi, DSIM_ESCMODE_REG); > > reg &= ~DSIM_STOP_STATE_CNT_MASK; > > reg |= > > DSIM_STOP_STATE_CNT(driver_data->reg_values[STOP_STATE_CNT]); > > > > + > > + if (!samsung_dsim_hw_is_exynos(dsi->plat_data->hw_type)) > > + reg |= DSIM_FORCE_STOP_STATE; > > + > > > > samsung_dsim_write(dsi, DSIM_ESCMODE_REG, reg); > > > > reg = DSIM_BTA_TIMEOUT(0xff) | DSIM_LPDR_TIMEOUT(0xffff); > > > > @@ -1340,6 +1344,9 @@ static void samsung_dsim_atomic_pre_enable(struct > > drm_bridge *bridge,> > > ret = samsung_dsim_init(dsi); > > if (ret) > > > > return; > > > > + > > + samsung_dsim_set_display_mode(dsi); > > + samsung_dsim_set_display_enable(dsi, true); > > > > } > > > > } > > > > @@ -1347,9 +1354,16 @@ static void samsung_dsim_atomic_enable(struct > > drm_bridge *bridge,> > > struct drm_bridge_state > > *old_bridge_state) > > > > { > > > > struct samsung_dsim *dsi = bridge_to_dsi(bridge); > > > > + u32 reg; > > > > - samsung_dsim_set_display_mode(dsi); > > - samsung_dsim_set_display_enable(dsi, true); > > + 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); > > + } > > > > dsi->state |= DSIM_STATE_VIDOUT_AVAILABLE; > > > > } > > > > @@ -1358,10 +1372,17 @@ static void samsung_dsim_atomic_disable(struct > > drm_bridge *bridge,> > > struct drm_bridge_state > > *old_bridge_state) > > > > { > > > > struct samsung_dsim *dsi = bridge_to_dsi(bridge); > > > > + u32 reg; > > > > 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); > > + } > > + > > > > dsi->state &= ~DSIM_STATE_VIDOUT_AVAILABLE; > > > > } > > > > -- > > 2.40.0 > > Hi Frieder, > > I found this patch to break mipi-dsi display on my board which has: > - FocalTech FT5406 10pt touch controller (with no interrupt) > - Powertip PH800480T013-IDF02 compatible panel > - Toshiba TC358762 compatible DSI to DBI bridge > - ATTINY based regulator used for backlight controller and panel enable > > I enable this via a dt overlay in a pending patch > imx8mm-venice-gw72xx-0x-rpidsi.dtso [1] which works on 6.4 but not > 6.5-rc1 which has this patch. > > The issue appears as: > [ 6.110585] samsung-dsim 32e60000.dsi: xfer timed out: 29 06 00 00 > 64 01 05 00 00 00 > [ 6.326588] tc358762 32e60000.dsi.0: error initializing bridge (-110) > > Instead of > [ 1.011729] samsung-dsim 32e10000.dsi: supply vddcore not found, > using dummy regulator > [ 1.019829] samsung-dsim 32e10000.dsi: supply vddio not found, > using dummy regulator > [ 5.649928] samsung-dsim 32e10000.dsi: > [drm:samsung_dsim_host_attach] Attached tc358762 device > > I'm curious what board/panel were you needing this for and do you have > any ideas why it broke my setup? > > I'm also curious what board/panel Alexander tested this with and if > Adam or Jagan (or others) have tested this with their hardware? I tested this with imx8mm and ti,sn65dsi83 DSI-LVDS bridge [1]. I don't know anything about tc358762, but I was trying to get tc9595 (DSI-DP bridge) running on a imx8mp based board. One of my problems was that the bridge requires LP-11 before reset release, which is currently not given using samsung-dsim and tc358767 driver. Maybe this is the case for you as well. AFAICS there is a lot more to do to get this running properly. Best regards, Alexander [1] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/ arch/arm64/boot/dts/freescale/imx8mp-tqma8mpql-mba8mpxl-lvds.dtso > best regards, > > Tim > [1] > https://patchwork.kernel.org/project/linux-arm-kernel/patch/20230711221124. > 2127186-1-tharvey@xxxxxxxxxxxxx/ -- TQ-Systems GmbH | Mühlstraße 2, Gut Delling | 82229 Seefeld, Germany Amtsgericht München, HRB 105018 Geschäftsführer: Detlef Schneider, Rüdiger Stahl, Stefan Schneider http://www.tq-group.com/
