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Date: Tue, 12 Nov 2024 17:36:09 -0600
From: Bjorn Helgaas <helgaas@kernel.org>
To: Krishna chaitanya chundru <quic_krichai@quicinc.com>
Cc: andersson@kernel.org, Bjorn Helgaas <bhelgaas@google.com>,
	Lorenzo Pieralisi <lpieralisi@kernel.org>,
	Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= <kw@linux.com>,
	Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>,
	Rob Herring <robh@kernel.org>,
	Krzysztof Kozlowski <krzk+dt@kernel.org>,
	Conor Dooley <conor+dt@kernel.org>,
	Konrad Dybcio <konradybcio@kernel.org>,
	cros-qcom-dts-watchers@chromium.org,
	Jingoo Han <jingoohan1@gmail.com>,
	Bartosz Golaszewski <brgl@bgdev.pl>, 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 v3 5/6] PCI: qcom: Add support for host_stop_link() &
 host_start_link()
Message-ID: <20241112233609.GA1868317@bhelgaas>
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In-Reply-To: <20241112-qps615_pwr-v3-5-29a1e98aa2b0@quicinc.com>

On Tue, Nov 12, 2024 at 08:31:37PM +0530, Krishna chaitanya chundru wrote:
> For the switches like QPS615 which needs to configure it before
> the PCIe link is established.
> 
> If the link is up, the boatloader might powered and configured the
> endpoint/switch already. In that case don't touch PCIe link else
> assert the PERST# and disable LTSSM bit so that PCIe controller
> will not participate in the link training as part of host_stop_link().

s/boatloader/bootloader/
s/might powered/might have powered/ ?

> De-assert the PERST# and enable LTSSM bit back in host_start_link().
> 
> Introduce ltssm_disable function op to stop the link training.