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Date:   Thu, 22 Dec 2022 18:56:27 +0300
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Subject: Re: [Patch v1 01/10] memory: tegra: add interconnect support for DRAM
 scaling in Tegra234
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From:   Dmitry Osipenko <digetx@gmail.com>
To:     Sumit Gupta <sumitg@nvidia.com>, treding@nvidia.com,
        krzysztof.kozlowski@linaro.org, dmitry.osipenko@collabora.com,
        viresh.kumar@linaro.org, rafael@kernel.org, jonathanh@nvidia.com,
        robh+dt@kernel.org, linux-kernel@vger.kernel.org,
        linux-tegra@vger.kernel.org, linux-pm@vger.kernel.org,
        devicetree@vger.kernel.org
Cc:     sanjayc@nvidia.com, ksitaraman@nvidia.com, ishah@nvidia.com,
        bbasu@nvidia.com
References: <20221220160240.27494-1-sumitg@nvidia.com>
 <20221220160240.27494-2-sumitg@nvidia.com>
 <62fc4a96-bab8-4d43-5278-3375e34431e7@gmail.com>
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21.12.2022 22:20, Dmitry Osipenko пишет:
> 20.12.2022 19:02, Sumit Gupta пишет:
>> +static int tegra_emc_icc_set_bw(struct icc_node *src, struct icc_node *dst)
>> +{
>> +	struct tegra186_emc *emc = to_tegra186_emc(dst->provider);
>> +	struct tegra_mc *mc = dev_get_drvdata(emc->dev->parent);
>> +	struct mrq_bwmgr_int_request bwmgr_req = { 0 };
>> +	struct mrq_bwmgr_int_response bwmgr_resp = { 0 };
>> +	struct tegra_icc_node *tnode = mc->curr_tnode;
>> +	struct tegra_bpmp_message msg;
>> +	int ret = 0;
>> +
>> +	/*
>> +	 * Same Src and Dst node will happen during boot from icc_node_add().
>> +	 * This can be used to pre-initialize and set bandwidth for all clients
>> +	 * before their drivers are loaded. We are skipping this case as for us,
>> +	 * the pre-initialization already happened in Bootloader(MB2) and BPMP-FW.
>> +	 */
>> +	if (src->id == dst->id)
>> +		return 0;
>> +
>> +	if (mc->curr_tnode->type == TEGRA_ICC_NISO)
> 
> The mc->curr_tnode usage looks suspicious, why you can't use src node?
> 

This function sets memory BW for a memory client and not for EMC.
Apparently, you should move the BW setting to tegra234_mc_icc_set() and
then tegra_emc_icc_set_bw() will be a noop.