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Date:   Mon, 16 Jan 2023 18:09:05 +0200
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Subject: Re: [PATCH net-next v2 2/3] net: ethernet: ti: am65-cpts: add pps
 support
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To:     Siddharth Vadapalli <s-vadapalli@ti.com>, davem@davemloft.net,
        edumazet@google.com, kuba@kernel.org, pabeni@redhat.com,
        robh+dt@kernel.org, krzysztof.kozlowski@linaro.org,
        krzysztof.kozlowski+dt@linaro.org, vigneshr@ti.com, nsekhar@ti.com
Cc:     netdev@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        srk@ti.com
References: <20230116085534.440820-1-s-vadapalli@ti.com>
 <20230116085534.440820-3-s-vadapalli@ti.com>
From:   Roger Quadros <rogerq@kernel.org>
In-Reply-To: <20230116085534.440820-3-s-vadapalli@ti.com>
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On 16/01/2023 10:55, Siddharth Vadapalli wrote:
> From: Grygorii Strashko <grygorii.strashko@ti.com>
> 
> CPTS doesn't have HW support for PPS ("pulse per second”) signal
> generation, but it can be modeled by using Time Sync Router and routing
> GenFx (periodic signal generator) output to CPTS_HWy_TS_PUSH (hardware time
> stamp) input, and configuring GenFx to generate 1sec pulses.
> 
>      +------------------------+
>      |          CPTS          |
>      |                        |
>  +--->CPTS_HW4_PUSH      GENFx+---+
>  |   |                        |   |
>  |   +------------------------+   |
>  |                                |
>  +--------------------------------+
> 
> Add corresponding support to am65-cpts driver. The DT property "ti,pps"
> has to be used to enable PPS support and configure pair
> [CPTS_HWy_TS_PUSH, GenFx].
> 
> Once enabled, PPS can be tested using ppstest tool:
>  # ./ppstest /dev/pps0
> 
> Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
> Signed-off-by: Siddharth Vadapalli <s-vadapalli@ti.com>

Reviewed-by: Roger Quadros <rogerq@kernel.org>