Hi Biju,
On Tue, Oct 28, 2025 3:07 PM, Biju Das wrote:
> > However, current defaults today in the driver are illegal for DPI,
> > even though they clearly work in real life on all the RZ/G2UL boards.
> > priv->mux_dsi_div_params.clksrc = 1; /* Use clk src 1 for DSI */
> > priv->mux_dsi_div_params.dsi_div_a = 1; /* Divided by 2 */
> > priv->mux_dsi_div_params.dsi_div_b = 2; /* Divided by 3 */
> >
> > Side note, that code comment "Use clk src 1 for DSI " is wrong ...it should
> > say "DPI"
>
> Why?
>
> This is correct as per hardware manual page 283 and [1] and [2]
For "DPI", both RZ/G2L and RZ/G2UL have the same table and same restrictions.
Valid values for register bits for DIVDSIA_SET = 1,2,3
Valid values for register bits for DIVDSIB_SET = 0
Remember, this is for DPI (not MIPI-DSI)
You were the one that pointed this out to me.
The driver needs to default to DPI mode (PLL5_TARGET_DPI ) because for RZ/G2UL,
no one is going to call the new API to change it.
> > priv->mux_dsi_div_params.dsi_div_a = 1; /* Divided by 2 */
> > priv->mux_dsi_div_params.dsi_div_b = 2; /* Divided by 3 */
So the current defaults of DIV_B = 2 is no good.
DIV_B must always be '0'
I just changed the code to this,
/* Default settings for DPI */
priv->mux_dsi_div_params.clksrc = 1;
priv->mux_dsi_div_params.dsi_div_a = 3; /* Divided by 8 */
priv->mux_dsi_div_params.dsi_div_b = 0; /* Divided by 1 */
dsi_div_ab = (priv->mux_dsi_div_params.dsi_div_b + 1) <<
priv->mux_dsi_div_params.dsi_div_a;
And on a RZ/G2UL (DPI) EVK, resolutions between 640x48 to 1920x1080 all work.
Do you agree? Or am I missing something?
Chris
