From: Brian Masney <bmasney@redhat.com>
To: Johan Hovold <johan+linaro@kernel.org>
Cc: "Stanimir Varbanov" <svarbanov@mm-sol.com>,
"Lorenzo Pieralisi" <lpieralisi@kernel.org>,
"Andy Gross" <agross@kernel.org>,
"Bjorn Andersson" <andersson@kernel.org>,
"Konrad Dybcio" <konrad.dybcio@somainline.org>,
"Bjorn Helgaas" <bhelgaas@google.com>,
"Rob Herring" <robh+dt@kernel.org>,
"Krzysztof Kozlowski" <krzysztof.kozlowski+dt@linaro.org>,
"Krzysztof Wilczyński" <kw@linux.com>,
"Manivannan Sadhasivam" <mani@kernel.org>,
"Krishna chaitanya chundru" <quic_krichai@quicinc.com>,
quic_vbadigan@quicinc.com, linux-arm-msm@vger.kernel.org,
linux-pci@vger.kernel.org, devicetree@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] PCI: qcom: Add basic interconnect support
Date: Wed, 19 Oct 2022 10:32:41 -0400 [thread overview]
Message-ID: <Y1AKiTkLa23idaf2@x1> (raw)
In-Reply-To: <20221017112449.2146-3-johan+linaro@kernel.org>
On Mon, Oct 17, 2022 at 01:24:49PM +0200, Johan Hovold wrote:
> + /*
> + * Some Qualcomm platforms require interconnect bandwidth constraints
> + * to be set before enabling interconnect clocks.
> + *
> + * Set an initial peak bandwidth corresponding to single-lane Gen 1
> + * for the pcie-mem path.
> + */
> + ret = icc_set_bw(pcie->icc_mem, 0, MBps_to_icc(250));
[snip]
> + speed = FIELD_GET(PCI_EXP_LNKSTA_CLS, status);
> + width = FIELD_GET(PCI_EXP_LNKSTA_NLW, status);
> +
> + switch (speed) {
> + case 1:
> + bw = MBps_to_icc(250);
> + break;
> + case 2:
> + bw = MBps_to_icc(500);
> + break;
> + default:
> + case 3:
> + bw = MBps_to_icc(985);
> + break;
> + }
Just curious: These platforms have a 4 lane PCIe bus. Why use 985
instead of 1000 for the maximum?
Brian
next prev parent reply other threads:[~2022-10-19 14:46 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-10-17 11:24 [PATCH 0/2] PCI: qcom: Add basic interconnect support Johan Hovold
2022-10-17 11:24 ` [PATCH 1/2] dt-bindings: PCI: qcom: Add SC8280XP/SA8540P interconnects Johan Hovold
2022-10-19 14:37 ` Krzysztof Kozlowski
2022-10-20 7:57 ` Johan Hovold
2022-10-20 12:29 ` Krzysztof Kozlowski
2022-10-21 6:40 ` Johan Hovold
2022-10-17 11:24 ` [PATCH 2/2] PCI: qcom: Add basic interconnect support Johan Hovold
2022-10-19 14:32 ` Brian Masney [this message]
2022-10-19 14:45 ` Johan Hovold
2022-10-20 16:49 ` Brian Masney
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=Y1AKiTkLa23idaf2@x1 \
--to=bmasney@redhat.com \
--cc=agross@kernel.org \
--cc=andersson@kernel.org \
--cc=bhelgaas@google.com \
--cc=devicetree@vger.kernel.org \
--cc=johan+linaro@kernel.org \
--cc=konrad.dybcio@somainline.org \
--cc=krzysztof.kozlowski+dt@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=mani@kernel.org \
--cc=quic_krichai@quicinc.com \
--cc=quic_vbadigan@quicinc.com \
--cc=robh+dt@kernel.org \
--cc=svarbanov@mm-sol.com \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.