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From: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
To: Bjorn Andersson <andersson@kernel.org>,
	 Konrad Dybcio <konrad.dybcio@linaro.org>,
	Vinod Koul <vkoul@kernel.org>,
	 Kishon Vijay Abraham I <kishon@kernel.org>,
	 Rob Herring <robh+dt@kernel.org>,
	 Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	 Conor Dooley <conor+dt@kernel.org>,
	cros-qcom-dts-watchers@chromium.org
Cc: linux-arm-msm@vger.kernel.org, linux-phy@lists.infradead.org,
	 devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
	 Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Subject: [PATCH 07/14] phy: qcom: qmp-pcie: Add a comment to clarify the use of "aux and "phy_aux" clocks
Date: Wed, 24 Jan 2024 13:06:35 +0530	[thread overview]
Message-ID: <20240124-pcie-aux-clk-fix-v1-7-d8a4852b6ba6@linaro.org> (raw)
In-Reply-To: <20240124-pcie-aux-clk-fix-v1-0-d8a4852b6ba6@linaro.org>

PCIe PHY hw on some SoCs require PCIE_PHY_AUX_CLK when the link enters L1SS
state. Historically, DTs of those SoCs passed this clock as "aux" clock.
But, SA8775P passed PCIE_PHY_AUX_CLK as "phy_aux" and PCIE_AUX_CLK as "aux"
mistakenly as the latter is not needed at all. Even though the SA8775P DT
got fixed, both of these clocks are kept here for backwards compatibility.

So add a comment to make it clear.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 drivers/phy/qualcomm/phy-qcom-qmp-pcie.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c b/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
index 9a220cbd9615..044e3c5ba341 100644
--- a/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
+++ b/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
@@ -2328,7 +2328,15 @@ static inline void qphy_clrbits(void __iomem *base, u32 offset, u32 val)
 	readl(base + offset);
 }
 
-/* list of clocks required by phy */
+/* list of clocks required by phy
+ *
+ * PCIe PHY hw on some SoCs require PCIE_PHY_AUX_CLK when the link enters L1SS
+ * state. Historically, DTs of those SoCs passed this clock as "aux" clock. But,
+ * SA8775P passed PCIE_PHY_AUX_CLK as "phy_aux" and PCIE_AUX_CLK as "aux"
+ * mistakenly as the latter is not needed at all. Even though the SA8775P DT got
+ * fixed, both of these clocks are kept here for backwards compatibility.
+ */
+
 static const char * const qmp_pciephy_clk_l[] = {
 	"aux", "cfg_ahb", "ref", "refgen", "rchng", "phy_aux",
 };

-- 
2.25.1


  parent reply	other threads:[~2024-01-24  7:37 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-01-24  7:36 [PATCH 00/14] Drop PCIE_AUX_CLK from the PCIe PHY nodes of Qcom SoCs Manivannan Sadhasivam
2024-01-24  7:36 ` [PATCH 01/14] dt-bindings: phy: qcom,ipq8074-qmp-pcie: Drop PCIE_AUX_CLK from pcie_phy node Manivannan Sadhasivam
2024-01-29 10:54   ` Krzysztof Kozlowski
2024-01-24  7:36 ` [PATCH 02/14] arm64: dts: qcom: ipq6018: " Manivannan Sadhasivam
2024-01-24  7:36 ` [PATCH 03/14] arm64: dts: qcom: ipq8074: Drop PCIE_AUX_CLK from pcie_phy nodes Manivannan Sadhasivam
2024-01-24  7:36 ` [PATCH 04/14] dt-bindings: phy: qcom,sc8280xp-qmp-pcie-phy: Fix the usage of aux clk Manivannan Sadhasivam
2024-01-29 10:54   ` Krzysztof Kozlowski
2024-01-30 17:14   ` Vinod Koul
2024-01-24  7:36 ` [PATCH 05/14] dt-bindings: phy: qcom,sc8280xp-qmp-pcie-phy: Document missing compatible for SM8350 3x2 PHY Manivannan Sadhasivam
2024-01-29 10:54   ` Krzysztof Kozlowski
2024-01-24  7:36 ` [PATCH 06/14] phy: qcom: qmp-pcie: Add a new compatible for SC7280 SoC Manivannan Sadhasivam
2024-01-24  7:36 ` Manivannan Sadhasivam [this message]
2024-01-24  7:36 ` [PATCH 08/14] arm64: dts: qcom: sc7280: Drop PCIE_AUX_CLK from pcie_phy node Manivannan Sadhasivam
2024-01-24  7:36 ` [PATCH 09/14] arm64: dts: qcom: sc8280xp: Drop PCIE_AUX_CLK from pcie_phy nodes Manivannan Sadhasivam
2024-01-24 13:22   ` Konrad Dybcio
2024-01-24  7:36 ` [PATCH 10/14] arm64: dts: qcom: sm8350: " Manivannan Sadhasivam
2024-01-24  7:36 ` [PATCH 11/14] arm64: dts: qcom: sm8450: Drop PCIE_AUX_CLK from pcie_phy node Manivannan Sadhasivam
2024-01-24  7:36 ` [PATCH 12/14] arm64: dts: qcom: sm8550: " Manivannan Sadhasivam
2024-01-24 12:26   ` neil.armstrong
2024-01-24  7:36 ` [PATCH 13/14] arm64: dts: qcom: sm8650: " Manivannan Sadhasivam
2024-01-24 12:34   ` neil.armstrong
2024-01-24  7:36 ` [PATCH 14/14] arm64: dts: qcom: sa8775p: Drop PCIE_AUX_CLK from pcie_phy nodes Manivannan Sadhasivam

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