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* [PATCH] PCI: qcom: Make sure PCIe is reset before init for rev 2.1.0
@ 2020-09-01 12:49 Ansuel Smith
  2020-09-01 16:55 ` Bjorn Andersson
  2020-09-07 11:02 ` Lorenzo Pieralisi
  0 siblings, 2 replies; 3+ messages in thread
From: Ansuel Smith @ 2020-09-01 12:49 UTC (permalink / raw)
  To: Stanimir Varbanov
  Cc: Ansuel Smith, stable, Andy Gross, Bjorn Andersson,
	Lorenzo Pieralisi, Rob Herring, Bjorn Helgaas, Philipp Zabel,
	linux-arm-msm, linux-pci, linux-kernel

Qsdk U-Boot can incorrectly leave the PCIe interface in an undefined
state if bootm command is used instead of bootipq. This is caused by the
not deinit of PCIe when bootm is called. Reset the PCIe before init
anyway to fix this U-Boot bug.

Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Fixes: 82a823833f4e ("PCI: qcom: Add Qualcomm PCIe controller driver")
Cc: stable@vger.kernel.org # v4.19+
---
 drivers/pci/controller/dwc/pcie-qcom.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
index 3aac77a295ba..82336bbaf8dc 100644
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -302,6 +302,9 @@ static void qcom_pcie_deinit_2_1_0(struct qcom_pcie *pcie)
 	reset_control_assert(res->por_reset);
 	reset_control_assert(res->ext_reset);
 	reset_control_assert(res->phy_reset);
+
+	writel(1, pcie->parf + PCIE20_PARF_PHY_CTRL);
+
 	regulator_bulk_disable(ARRAY_SIZE(res->supplies), res->supplies);
 }
 
@@ -314,6 +317,16 @@ static int qcom_pcie_init_2_1_0(struct qcom_pcie *pcie)
 	u32 val;
 	int ret;
 
+	/* reset the PCIe interface as uboot can leave it undefined state */
+	reset_control_assert(res->pci_reset);
+	reset_control_assert(res->axi_reset);
+	reset_control_assert(res->ahb_reset);
+	reset_control_assert(res->por_reset);
+	reset_control_assert(res->ext_reset);
+	reset_control_assert(res->phy_reset);
+
+	writel(1, pcie->parf + PCIE20_PARF_PHY_CTRL);
+
 	ret = regulator_bulk_enable(ARRAY_SIZE(res->supplies), res->supplies);
 	if (ret < 0) {
 		dev_err(dev, "cannot enable regulators\n");
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 3+ messages in thread
* Re: [PATCH] PCI: qcom: Make sure PCIe is reset before init for rev 2.1.0
  2020-09-01 12:49 [PATCH] PCI: qcom: Make sure PCIe is reset before init for rev 2.1.0 Ansuel Smith
@ 2020-09-01 16:55 ` Bjorn Andersson
  2020-09-07 11:02 ` Lorenzo Pieralisi
  1 sibling, 0 replies; 3+ messages in thread
From: Bjorn Andersson @ 2020-09-01 16:55 UTC (permalink / raw)
  To: Ansuel Smith
  Cc: Stanimir Varbanov, stable, Andy Gross, Lorenzo Pieralisi,
	Rob Herring, Bjorn Helgaas, Philipp Zabel, linux-arm-msm,
	linux-pci, linux-kernel

On Tue 01 Sep 07:49 CDT 2020, Ansuel Smith wrote:

> Qsdk U-Boot can incorrectly leave the PCIe interface in an undefined
> state if bootm command is used instead of bootipq. This is caused by the
> not deinit of PCIe when bootm is called. Reset the PCIe before init
> anyway to fix this U-Boot bug.
> 

Looks sensible.

Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>

Regards,
Bjorn

> Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
> Fixes: 82a823833f4e ("PCI: qcom: Add Qualcomm PCIe controller driver")
> Cc: stable@vger.kernel.org # v4.19+
> ---
>  drivers/pci/controller/dwc/pcie-qcom.c | 13 +++++++++++++
>  1 file changed, 13 insertions(+)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
> index 3aac77a295ba..82336bbaf8dc 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
> @@ -302,6 +302,9 @@ static void qcom_pcie_deinit_2_1_0(struct qcom_pcie *pcie)
>  	reset_control_assert(res->por_reset);
>  	reset_control_assert(res->ext_reset);
>  	reset_control_assert(res->phy_reset);
> +
> +	writel(1, pcie->parf + PCIE20_PARF_PHY_CTRL);
> +
>  	regulator_bulk_disable(ARRAY_SIZE(res->supplies), res->supplies);
>  }
>  
> @@ -314,6 +317,16 @@ static int qcom_pcie_init_2_1_0(struct qcom_pcie *pcie)
>  	u32 val;
>  	int ret;
>  
> +	/* reset the PCIe interface as uboot can leave it undefined state */
> +	reset_control_assert(res->pci_reset);
> +	reset_control_assert(res->axi_reset);
> +	reset_control_assert(res->ahb_reset);
> +	reset_control_assert(res->por_reset);
> +	reset_control_assert(res->ext_reset);
> +	reset_control_assert(res->phy_reset);
> +
> +	writel(1, pcie->parf + PCIE20_PARF_PHY_CTRL);
> +
>  	ret = regulator_bulk_enable(ARRAY_SIZE(res->supplies), res->supplies);
>  	if (ret < 0) {
>  		dev_err(dev, "cannot enable regulators\n");
> -- 
> 2.27.0
> 

^ permalink raw reply	[flat|nested] 3+ messages in thread
* Re: [PATCH] PCI: qcom: Make sure PCIe is reset before init for rev 2.1.0
  2020-09-01 12:49 [PATCH] PCI: qcom: Make sure PCIe is reset before init for rev 2.1.0 Ansuel Smith
  2020-09-01 16:55 ` Bjorn Andersson
@ 2020-09-07 11:02 ` Lorenzo Pieralisi
  1 sibling, 0 replies; 3+ messages in thread
From: Lorenzo Pieralisi @ 2020-09-07 11:02 UTC (permalink / raw)
  To: Ansuel Smith
  Cc: Stanimir Varbanov, stable, Andy Gross, Bjorn Andersson,
	Rob Herring, Bjorn Helgaas, Philipp Zabel, linux-arm-msm,
	linux-pci, linux-kernel

On Tue, Sep 01, 2020 at 02:49:54PM +0200, Ansuel Smith wrote:
> Qsdk U-Boot can incorrectly leave the PCIe interface in an undefined
> state if bootm command is used instead of bootipq. This is caused by the
> not deinit of PCIe when bootm is called. Reset the PCIe before init
> anyway to fix this U-Boot bug.
> 
> Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
> Fixes: 82a823833f4e ("PCI: qcom: Add Qualcomm PCIe controller driver")
> Cc: stable@vger.kernel.org # v4.19+
> ---
>  drivers/pci/controller/dwc/pcie-qcom.c | 13 +++++++++++++
>  1 file changed, 13 insertions(+)

Applied to pci/qcom, thanks.

Lorenzo

> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
> index 3aac77a295ba..82336bbaf8dc 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
> @@ -302,6 +302,9 @@ static void qcom_pcie_deinit_2_1_0(struct qcom_pcie *pcie)
>  	reset_control_assert(res->por_reset);
>  	reset_control_assert(res->ext_reset);
>  	reset_control_assert(res->phy_reset);
> +
> +	writel(1, pcie->parf + PCIE20_PARF_PHY_CTRL);
> +
>  	regulator_bulk_disable(ARRAY_SIZE(res->supplies), res->supplies);
>  }
>  
> @@ -314,6 +317,16 @@ static int qcom_pcie_init_2_1_0(struct qcom_pcie *pcie)
>  	u32 val;
>  	int ret;
>  
> +	/* reset the PCIe interface as uboot can leave it undefined state */
> +	reset_control_assert(res->pci_reset);
> +	reset_control_assert(res->axi_reset);
> +	reset_control_assert(res->ahb_reset);
> +	reset_control_assert(res->por_reset);
> +	reset_control_assert(res->ext_reset);
> +	reset_control_assert(res->phy_reset);
> +
> +	writel(1, pcie->parf + PCIE20_PARF_PHY_CTRL);
> +
>  	ret = regulator_bulk_enable(ARRAY_SIZE(res->supplies), res->supplies);
>  	if (ret < 0) {
>  		dev_err(dev, "cannot enable regulators\n");
> -- 
> 2.27.0
> 

^ permalink raw reply	[flat|nested] 3+ messages in thread
end of thread, other threads:[~2020-09-07 11:35 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2020-09-01 12:49 [PATCH] PCI: qcom: Make sure PCIe is reset before init for rev 2.1.0 Ansuel Smith
2020-09-01 16:55 ` Bjorn Andersson
2020-09-07 11:02 ` Lorenzo Pieralisi

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