On i.MX8QM, PCIe link can't be re-established again in
dw_pcie_resume_noirq(), if the LTSSM_EN bit is not cleared properly in
dw_pcie_suspend_noirq().

Add dw_pcie_stop_link() into dw_pcie_suspend_noirq() to fix this issue and
keep symmetric in suspend/resume function since there is
dw_pcie_start_link() in dw_pcie_resume_noirq().

Fixes: 4774faf854f5 ("PCI: dwc: Implement generic suspend/resume functionality")
Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
---
 drivers/pci/controller/dwc/pcie-designware-host.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index cb8c3c2bcc79..9ca33895456f 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -952,6 +952,7 @@ int dw_pcie_suspend_noirq(struct dw_pcie *pci)
 		}
 	}
 
+	dw_pcie_stop_link(pci);
 	if (pci->pp.ops->deinit)
 		pci->pp.ops->deinit(&pci->pp);
 
-- 
2.37.1

In subject,

s/Do/Always

On Wed, Sep 25, 2024 at 01:48:37PM +0800, Richard Zhu wrote:
> On i.MX8QM, PCIe link can't be re-established again in
> dw_pcie_resume_noirq(), if the LTSSM_EN bit is not cleared properly in
> dw_pcie_suspend_noirq().
> 
> Add dw_pcie_stop_link() into dw_pcie_suspend_noirq() to fix this issue and
> keep symmetric in suspend/resume function since there is
> dw_pcie_start_link() in dw_pcie_resume_noirq().
> 
> Fixes: 4774faf854f5 ("PCI: dwc: Implement generic suspend/resume functionality")
> Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>

Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

- Mani

> ---
>  drivers/pci/controller/dwc/pcie-designware-host.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
> index cb8c3c2bcc79..9ca33895456f 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-host.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-host.c
> @@ -952,6 +952,7 @@ int dw_pcie_suspend_noirq(struct dw_pcie *pci)
>  		}
>  	}
>  
> +	dw_pcie_stop_link(pci);
>  	if (pci->pp.ops->deinit)
>  		pci->pp.ops->deinit(&pci->pp);
>  
> -- 
> 2.37.1
> 

-- 
மணிவண்ணன் சதாசிவம்

On Wed, Sep 25, 2024 at 01:48:37PM +0800, Richard Zhu wrote:
> On i.MX8QM, PCIe link can't be re-established again in
> dw_pcie_resume_noirq(), if the LTSSM_EN bit is not cleared properly in
> dw_pcie_suspend_noirq().
>
> Add dw_pcie_stop_link() into dw_pcie_suspend_noirq() to fix this issue and
> keep symmetric in suspend/resume function since there is
> dw_pcie_start_link() in dw_pcie_resume_noirq().
>
> Fixes: 4774faf854f5 ("PCI: dwc: Implement generic suspend/resume functionality")
> Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>

Reviewed-by: Frank Li <Frank.Li@nxp.com>

> ---
>  drivers/pci/controller/dwc/pcie-designware-host.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
> index cb8c3c2bcc79..9ca33895456f 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-host.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-host.c
> @@ -952,6 +952,7 @@ int dw_pcie_suspend_noirq(struct dw_pcie *pci)
>  		}
>  	}
>
> +	dw_pcie_stop_link(pci);
>  	if (pci->pp.ops->deinit)
>  		pci->pp.ops->deinit(&pci->pp);
>
> --
> 2.37.1
>