linux-kernel - Re: [PATCH v3 04/10] interconnect: qcom: icc-rpm: Check for node-specific rate coefficients

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <a4ccb1ec-5444-49bc-a3a3-832e554daeb6@linaro.org>
Date:   Thu, 10 Aug 2023 15:28:07 +0200
From:   Konrad Dybcio <konrad.dybcio@...aro.org>
To:     Stephan Gerhold <stephan@...hold.net>
Cc:     Andy Gross <agross@...nel.org>,
        Bjorn Andersson <andersson@...nel.org>,
        Georgi Djakov <djakov@...nel.org>,
        Michael Turquette <mturquette@...libre.com>,
        Stephen Boyd <sboyd@...nel.org>,
        Marijn Suijten <marijn.suijten@...ainline.org>,
        linux-arm-msm@...r.kernel.org, linux-pm@...r.kernel.org,
        linux-kernel@...r.kernel.org, linux-clk@...r.kernel.org
Subject: Re: [PATCH v3 04/10] interconnect: qcom: icc-rpm: Check for
 node-specific rate coefficients

On 10.08.2023 09:26, Stephan Gerhold wrote:
> On Tue, Aug 08, 2023 at 01:43:35PM +0200, Konrad Dybcio wrote:
>> Some nodes may have different coefficients than the general values for
>> bus they're attached to. Check for that and use them if present. See
>> [1], [2] for reference.
>>
>> [1] https://github.com/sonyxperiadev/kernel/commit/7456d9779af9ad6bb9c7ee6f33d5c5a8d3648e24
>> [2] https://github.com/artem/android_kernel_sony_msm8996/commit/bf7a8985dcaf0eab5bc2562d2d6775e7e29c0f30
>> Signed-off-by: Konrad Dybcio <konrad.dybcio@...aro.org>
>> ---
>>  drivers/interconnect/qcom/icc-rpm.c | 14 ++++++++++----
>>  drivers/interconnect/qcom/icc-rpm.h |  5 +++++
>>  2 files changed, 15 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/interconnect/qcom/icc-rpm.c b/drivers/interconnect/qcom/icc-rpm.c
>> index 1d3af4e9ead8..9c40314e03b5 100644
>> --- a/drivers/interconnect/qcom/icc-rpm.c
>> +++ b/drivers/interconnect/qcom/icc-rpm.c
>> @@ -300,14 +300,14 @@ static u64 qcom_icc_calc_rate(struct qcom_icc_provider *qp, struct qcom_icc_node
>>  	else
>>  		agg_avg_rate = qn->sum_avg[ctx];
>>  
>> -	if (qp->ab_coeff) {
>> -		agg_avg_rate = agg_avg_rate * qp->ab_coeff;
>> +	if (qn->ab_coeff) {
>> +		agg_avg_rate = agg_avg_rate * qn->ab_coeff;
>>  		agg_avg_rate = div_u64(agg_avg_rate, 100);
>>  	}
>>  
>> -	if (qp->ib_coeff) {
>> +	if (qn->ib_coeff) {
>>  		agg_peak_rate = qn->max_peak[ctx] * 100;
>> -		agg_peak_rate = div_u64(qn->max_peak[ctx], qp->ib_coeff);
>> +		agg_peak_rate = div_u64(qn->max_peak[ctx], qn->ib_coeff);
>>  	} else {
>>  		agg_peak_rate = qn->max_peak[ctx];
>>  	}
>> @@ -563,6 +563,12 @@ int qnoc_probe(struct platform_device *pdev)
>>  	for (i = 0; i < num_nodes; i++) {
>>  		size_t j;
>>  
>> +		if (!qnodes[i]->ab_coeff)
>> +			qnodes[i]->ab_coeff = qp->ab_coeff;
>> +
>> +		if (!qnodes[i]->ib_coeff)
>> +			qnodes[i]->ib_coeff = qp->ib_coeff;
>> +
>>  		node = icc_node_create(qnodes[i]->id);
>>  		if (IS_ERR(node)) {
>>  			ret = PTR_ERR(node);
>> diff --git a/drivers/interconnect/qcom/icc-rpm.h b/drivers/interconnect/qcom/icc-rpm.h
>> index f9ef16f570be..4abf99ce2690 100644
>> --- a/drivers/interconnect/qcom/icc-rpm.h
>> +++ b/drivers/interconnect/qcom/icc-rpm.h
>> @@ -103,6 +103,9 @@ struct qcom_icc_qos {
>>   * @mas_rpm_id:	RPM id for devices that are bus masters
>>   * @slv_rpm_id:	RPM id for devices that are bus slaves
>>   * @qos: NoC QoS setting parameters
>> + * @ab_coeff: a percentage-based coefficient for compensating the AB calculations
>> + * @ib_coeff: an inverse-percentage-based coefficient for compensating the IB calculations
>> + * @bus_clk_rate: a pointer to an array containing bus clock rates in Hz
> 
> Nitpick: The doc comment needs to be moved to the earlier patch as well. :)
Gah :P

Konrad