On Tue, Sep 3, 2019 at 4:38 PM Stephan Gerhold <stephan@xxxxxxxxxxx> wrote: > On Tue, Sep 03, 2019 at 11:15:12AM +0200, Linus Walleij wrote: > > /* > > * This is the time to perform LP->HS on D-PHY > > * FIXME: nowhere to get this from: DT property on the DSI? > > + * values like 48 and 72 seen in the vendor code. > > */ > > - val |= 0 << DSI_VID_DPHY_TIME_REG_WAKEUP_TIME_SHIFT; > > + val |= 48 << DSI_VID_DPHY_TIME_REG_WAKEUP_TIME_SHIFT; > > writel(val, d->regs + DSI_VID_DPHY_TIME); > > I just want to note that the Samsung S3 Mini (golden) seems to use 88 > here. I suppose we will need to see how important this property is, > or if panels can also work with a slightly wrong value. Yeah maybe we should just figure out what to do about this. This is the wakeup time, in clock cycles, for a LP->HS transition on the D-PHY. The panel driver kind of knows knows this timing, so I guess we should add a field to struct mipi_dsi_device such as unsigned int lp_to_hs_wakep, but it needs to come from the device tree since per the manual this value is system dependent: "reg_wakeup_time must be shorter than line duration and depends on the D-PHY cell plus some pipelines delays inserted by the DSI link. This value strongly depends on the PLL programming and as it is a mix of analog and digital timing, it is practically impossible to provide a general formula. By the way, it has to be characterized at system level (validation and/or simulation)." > > - writel(blkeol_pck, d->regs + DSI_VID_VCA_SETTING2); > > + writel((blkeol_pck & DSI_VID_VCA_SETTING2_EXACT_BURST_LIMIT_MASK) > > + << DSI_VID_VCA_SETTING2_EXACT_BURST_LIMIT_SHIFT, > > + d->regs + DSI_VID_VCA_SETTING2); > > It does not make a difference in this case because SHIFT = 0, > but shouldn't you normally shift before applying the mask? > Otherwise, you would wipe out the lower bits before you shift them. OK you're right, I fix it up and resend. Yours, Linus Walleij _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
