From: Krishna Chaitanya Chundru <quic_krichai@quicinc.com>
To: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Cc: "Bjorn Andersson" <andersson@kernel.org>,
"Konrad Dybcio" <konrad.dybcio@linaro.org>,
"Rob Herring" <robh@kernel.org>,
"Krzysztof Kozlowski" <krzysztof.kozlowski+dt@linaro.org>,
"Conor Dooley" <conor+dt@kernel.org>,
"Lorenzo Pieralisi" <lpieralisi@kernel.org>,
"Krzysztof Wilczyński" <kw@linux.com>,
"Bjorn Helgaas" <bhelgaas@google.com>,
johan+linaro@kernel.org, bmasney@redhat.com, djakov@kernel.org,
linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org,
linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org,
vireshk@kernel.org, quic_vbadigan@quicinc.com,
quic_skananth@quicinc.com, quic_nitegupt@quicinc.com,
quic_parass@quicinc.com, krzysztof.kozlowski@linaro.org
Subject: Re: [PATCH v10 4/6] arm64: dts: qcom: sm8450: Add OPP table support to PCIe
Date: Mon, 22 Apr 2024 22:25:06 +0530 [thread overview]
Message-ID: <aaee8605-848f-fe9c-63aa-af4ae2d399a6@quicinc.com> (raw)
In-Reply-To: <20240422144431.GE9775@thinkpad>
On 4/22/2024 8:14 PM, Manivannan Sadhasivam wrote:
> On Tue, Apr 09, 2024 at 03:43:22PM +0530, Krishna chaitanya chundru wrote:
>> PCIe needs to choose the appropriate performance state of RPMh power
>
> 'PCIe host controller driver'
>
>> domain and interconnect bandwidth based up on the PCIe data rate.
>
> 'based on the PCIe data rate'
>
>>
>> Add the OPP table support to specify RPMh performance states and
>
> 'Hence, add...'
>
>> interconnect peak bandwidth.
>>
>> Different link configurations may share the same aggregate bandwidth,
>
> 'It should be noted that the different...'
>
>> e.g., a 2.5 GT/s x2 link and a 5.0 GT/s x1 link have the same bandwidth
>> and share the same OPP entry.
>>
>> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
>> ---
>> arch/arm64/boot/dts/qcom/sm8450.dtsi | 77 ++++++++++++++++++++++++++++++++++++
>> 1 file changed, 77 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/qcom/sm8450.dtsi b/arch/arm64/boot/dts/qcom/sm8450.dtsi
>> index 615296e13c43..9dfe16012726 100644
>> --- a/arch/arm64/boot/dts/qcom/sm8450.dtsi
>> +++ b/arch/arm64/boot/dts/qcom/sm8450.dtsi
>> @@ -1855,7 +1855,35 @@ &mc_virt SLAVE_EBI1 QCOM_ICC_TAG_ALWAYS>,
>> pinctrl-names = "default";
>> pinctrl-0 = <&pcie0_default_state>;
>>
>> + operating-points-v2 = <&pcie0_opp_table>;
>> +
>> status = "disabled";
>> +
>> + pcie0_opp_table: opp-table {
>> + compatible = "operating-points-v2";
>> +
>> + /* GEN 1 x1 */
>> + opp-2500000 {
>> + opp-hz = /bits/ 64 <2500000>;
>> + required-opps = <&rpmhpd_opp_low_svs>;
>> + opp-peak-kBps = <250000 1>;
>> + };
>> +
>> + /* GEN 2 x1 */
>> + opp-5000000 {
>> + opp-hz = /bits/ 64 <5000000>;
>> + required-opps = <&rpmhpd_opp_low_svs>;
>> + opp-peak-kBps = <500000 1>;
>> + };
>> +
>> + /* GEN 3 x1 */
>> + opp-8000000 {
>> + opp-hz = /bits/ 64 <8000000>;
>
> I doubt this value. See below...
>
>> + required-opps = <&rpmhpd_opp_nom>;
>> + opp-peak-kBps = <984500 1>;
>> + };
>> + };
>> +
>> };
>>
>> pcie0_phy: phy@1c06000 {
>> @@ -1982,7 +2010,56 @@ &mc_virt SLAVE_EBI1 QCOM_ICC_TAG_ALWAYS>,
>> pinctrl-names = "default";
>> pinctrl-0 = <&pcie1_default_state>;
>>
>> + operating-points-v2 = <&pcie1_opp_table>;
>> +
>> status = "disabled";
>> +
>> + pcie1_opp_table: opp-table {
>> + compatible = "operating-points-v2";
>> +
>> + /* GEN 1 x1 */
>> + opp-2500000 {
>> + opp-hz = /bits/ 64 <2500000>;
>> + required-opps = <&rpmhpd_opp_low_svs>;
>> + opp-peak-kBps = <250000 1>;
>> + };
>> +
>> + /* GEN 1 x2 GEN 2 x1 */
>> + opp-5000000 {
>> + opp-hz = /bits/ 64 <5000000>;
>> + required-opps = <&rpmhpd_opp_low_svs>;
>> + opp-peak-kBps = <500000 1>;
>> + };
>> +
>> + /* GEN 2 x2 */
>> + opp-10000000 {
>> + opp-hz = /bits/ 64 <10000000>;
>> + required-opps = <&rpmhpd_opp_low_svs>;
>> + opp-peak-kBps = <1000000 1>;
>> + };
>> +
>> + /* GEN 3 x1 */
>> + opp-8000000 {
>> + opp-hz = /bits/ 64 <8000000>;
>
> GEN 3 x1 frequency is lower than GEN 2 x2? This looks strange. Both should be of
> same frequency.
>
Gen2 is 5GT/s where as GEN3 is 8GT/s. so the freq for 3 x1(8 x1 GT/s) is
less than Gen2 x2(5 x2 GT/s)
- Krishna Chaitanya.
>> + required-opps = <&rpmhpd_opp_nom>;
>> + opp-peak-kBps = <984500 1>;
>> + };
>> +
>> + /* GEN 3 x2 GEN 4 x1 */
>
> 'GEN 3 x2 and GEN 4 x1'
>
> - Mani
>
next prev parent reply other threads:[~2024-04-22 16:55 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-04-09 10:13 [PATCH v10 0/6] PCI: qcom: Add support for OPP Krishna chaitanya chundru
2024-04-09 10:13 ` [PATCH v10 1/6] arm64: dts: qcom: sm8450: Add interconnect path to PCIe node Krishna chaitanya chundru
2024-04-09 10:13 ` [PATCH v10 2/6] PCI: qcom: Add ICC bandwidth vote for CPU to PCIe path Krishna chaitanya chundru
2024-04-22 14:31 ` Manivannan Sadhasivam
2024-04-09 10:13 ` [PATCH v10 3/6] dt-bindings: pci: qcom: Add OPP table Krishna chaitanya chundru
2024-04-09 10:13 ` [PATCH v10 4/6] arm64: dts: qcom: sm8450: Add OPP table support to PCIe Krishna chaitanya chundru
2024-04-22 14:44 ` Manivannan Sadhasivam
2024-04-22 16:55 ` Krishna Chaitanya Chundru [this message]
2024-04-22 17:08 ` Manivannan Sadhasivam
2024-04-09 10:13 ` [PATCH v10 5/6] PCI: Bring the PCIe speed to MBps logic to new pcie_link_speed_to_mbps() Krishna chaitanya chundru
2024-04-09 15:07 ` Bjorn Helgaas
2024-04-09 10:13 ` [PATCH v10 6/6] PCI: qcom: Add OPP support to scale performance state of power domain Krishna chaitanya chundru
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=aaee8605-848f-fe9c-63aa-af4ae2d399a6@quicinc.com \
--to=quic_krichai@quicinc.com \
--cc=andersson@kernel.org \
--cc=bhelgaas@google.com \
--cc=bmasney@redhat.com \
--cc=conor+dt@kernel.org \
--cc=devicetree@vger.kernel.org \
--cc=djakov@kernel.org \
--cc=johan+linaro@kernel.org \
--cc=konrad.dybcio@linaro.org \
--cc=krzysztof.kozlowski+dt@linaro.org \
--cc=krzysztof.kozlowski@linaro.org \
--cc=kw@linux.com \
--cc=linux-arm-msm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pci@vger.kernel.org \
--cc=lpieralisi@kernel.org \
--cc=manivannan.sadhasivam@linaro.org \
--cc=quic_nitegupt@quicinc.com \
--cc=quic_parass@quicinc.com \
--cc=quic_skananth@quicinc.com \
--cc=quic_vbadigan@quicinc.com \
--cc=robh@kernel.org \
--cc=vireshk@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).