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Message-ID: <1f1552cd-d16b-fea0-2816-9bb3a2373ff5@kernel.org>
Date:   Fri, 4 Nov 2022 14:57:08 +0200
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Subject: Re: [PATCH v7 3/5] remoteproc: pru: Make sysfs entries read-only for
 PRU client driven boots
Content-Language: en-US
To:     MD Danish Anwar <danishanwar@ti.com>,
        Mathieu Poirier <mathieu.poirier@linaro.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Rob Herring <robh+dt@kernel.org>
Cc:     Suman Anna <s-anna@ti.com>, "Andrew F . Davis" <afd@ti.com>,
        nm@ti.com, vigneshr@ti.com, srk@ti.com,
        linux-remoteproc@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org
References: <20221031073801.130541-1-danishanwar@ti.com>
 <20221031073801.130541-4-danishanwar@ti.com>
From:   Roger Quadros <rogerq@kernel.org>
In-Reply-To: <20221031073801.130541-4-danishanwar@ti.com>
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On 31/10/2022 09:37, MD Danish Anwar wrote:
> From: Suman Anna <s-anna@ti.com>
> 
> The PRU remoteproc driver is not configured for 'auto-boot' by default,
> and allows to be booted either by in-kernel PRU client drivers or by
> userspace using the generic remoteproc sysfs interfaces. The sysfs
> interfaces should not be permitted to change the remoteproc firmwares
> or states when a PRU is being managed by an in-kernel client driver.
> Use the newly introduced remoteproc generic 'sysfs_read_only' flag to
> provide these restrictions by setting and clearing it appropriately
> during the PRU acquire and release steps.
> 
> Signed-off-by: Suman Anna <s-anna@ti.com>
> Co-developed-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>
> Signed-off-by: Grzegorz Jaszczyk <grzegorz.jaszczyk@linaro.org>
> Signed-off-by: Puranjay Mohan <p-mohan@ti.com>

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

> ---
>  drivers/remoteproc/pru_rproc.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/remoteproc/pru_rproc.c b/drivers/remoteproc/pru_rproc.c
> index 9ba73cfc29e2..14eb27bb5f3f 100644
> --- a/drivers/remoteproc/pru_rproc.c
> +++ b/drivers/remoteproc/pru_rproc.c
> @@ -230,6 +230,7 @@ struct rproc *pru_rproc_get(struct device_node *np, int index,
>  	}
>  
>  	pru->client_np = np;
> +	rproc->sysfs_read_only = true;
>  
>  	mutex_unlock(&pru->lock);
>  
> @@ -268,6 +269,7 @@ void pru_rproc_put(struct rproc *rproc)
>  	}
>  
>  	pru->client_np = NULL;
> +	rproc->sysfs_read_only = false;
>  	mutex_unlock(&pru->lock);
>  
>  	rproc_put(rproc);