Re: [RFC PATCH v4 8/8] arm64: tegra: Add Tegra VI CSI support in device tree

From: Sowjanya Komatineni
Date: Sun Mar 15 2020 - 18:22:04 EST



On 3/15/20 5:54 AM, Dmitry Osipenko wrote:
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15.03.2020 04:46, Sowjanya Komatineni ÐÐÑÐÑ:
Tegra210 contains VI controller for video input capture from MIPI
CSI camera sensors and also supports built-in test pattern generator.

CSI ports can be one-to-one mapped to VI channels for capturing from
an external sensor or from built-in test pattern generator.

This patch adds support for VI and CSI and enables them in Tegra210
device tree.

Signed-off-by: Sowjanya Komatineni <skomatineni@xxxxxxxxxx>
---
Hello Sowjanya,

...
+
+ pd_venc: venc {
+ clocks = <&tegra_car TEGRA210_CLK_VI>,
+ <&tegra_car TEGRA210_CLK_CSI>;
+ resets = <&tegra_car 20>,
What is the clock #20?

Hi Dmitry,

20 is VI_RST not defined in include/dt-bindings/reset/tegra210-car.h

Will add define and will fix to use it.



+ <&tegra_car TEGRA210_CLK_CSI>,
+ <&mc TEGRA210_MC_RESET_VI>;
Does this order means that memory controller will be reset *after*
resetting the CSI/VI hardware? This is incorrect reset sequence.

The memory controller reset should be kept asserted during of the time
of the hardware resetting procedure.

The correct sequence should be as follows:

1. Assert MC
2. Reset VI
3. Deassert MC
Right, will fix order. Thanks