diff mbox series

[v8,06/10] PCI: dwc: ep: Call dw_pcie_ep_init_registers() API directly from all glue drivers

Message ID 20240224-pci-dbi-rework-v8-6-64c7fd0cfe64@linaro.org (mailing list archive)
State New, archived
Headers show
Series PCI: dwc: ep: Fix DBI access failure for drivers requiring refclk from host | expand

Commit Message

Manivannan Sadhasivam Feb. 24, 2024, 6:54 a.m. UTC
Currently, dw_pcie_ep_init_registers() API is directly called by the glue
drivers requiring active refclk from host. But for the other drivers, it is
getting called implicitly by dw_pcie_ep_init(). This is due to the fact
that this API initializes DWC EP specific registers and that requires an
active refclk (either from host or generated locally by endpoint itsef).

But, this causes a discrepancy among the glue drivers. So to avoid this
confusion, let's call this API directly from all glue drivers irrespective
of refclk dependency. Only difference here is that the drivers requiring
refclk from host will call this API only after the refclk is received and
other drivers without refclk dependency will call this API right after
dw_pcie_ep_init().

This change will also allow us to remove the "core_init_notifier" flag in
the later commits.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 drivers/pci/controller/dwc/pci-dra7xx.c           |  7 +++++++
 drivers/pci/controller/dwc/pci-imx6.c             |  8 ++++++++
 drivers/pci/controller/dwc/pci-keystone.c         |  9 +++++++++
 drivers/pci/controller/dwc/pci-layerscape-ep.c    |  7 +++++++
 drivers/pci/controller/dwc/pcie-designware-ep.c   | 22 ----------------------
 drivers/pci/controller/dwc/pcie-designware-plat.c |  9 +++++++++
 drivers/pci/controller/dwc/pcie-rcar-gen4.c       | 12 +++++++++++-
 drivers/pci/controller/dwc/pcie-uniphier-ep.c     | 13 ++++++++++++-
 8 files changed, 63 insertions(+), 24 deletions(-)

Comments

Frank Li Feb. 26, 2024, 5:04 p.m. UTC | #1
On Sat, Feb 24, 2024 at 12:24:12PM +0530, Manivannan Sadhasivam wrote:
> Currently, dw_pcie_ep_init_registers() API is directly called by the glue
> drivers requiring active refclk from host. But for the other drivers, it is
> getting called implicitly by dw_pcie_ep_init(). This is due to the fact
> that this API initializes DWC EP specific registers and that requires an
> active refclk (either from host or generated locally by endpoint itsef).
> 
> But, this causes a discrepancy among the glue drivers. So to avoid this
> confusion, let's call this API directly from all glue drivers irrespective
> of refclk dependency. Only difference here is that the drivers requiring
> refclk from host will call this API only after the refclk is received and
> other drivers without refclk dependency will call this API right after
> dw_pcie_ep_init().
> 
> This change will also allow us to remove the "core_init_notifier" flag in
> the later commits.
> 
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> ---
>  drivers/pci/controller/dwc/pci-dra7xx.c           |  7 +++++++
>  drivers/pci/controller/dwc/pci-imx6.c             |  8 ++++++++
>  drivers/pci/controller/dwc/pci-keystone.c         |  9 +++++++++
>  drivers/pci/controller/dwc/pci-layerscape-ep.c    |  7 +++++++
>  drivers/pci/controller/dwc/pcie-designware-ep.c   | 22 ----------------------
>  drivers/pci/controller/dwc/pcie-designware-plat.c |  9 +++++++++
>  drivers/pci/controller/dwc/pcie-rcar-gen4.c       | 12 +++++++++++-
>  drivers/pci/controller/dwc/pcie-uniphier-ep.c     | 13 ++++++++++++-
>  8 files changed, 63 insertions(+), 24 deletions(-)
> 
> diff --git a/drivers/pci/controller/dwc/pci-dra7xx.c b/drivers/pci/controller/dwc/pci-dra7xx.c
> index 0e406677060d..395042b29ffc 100644
> --- a/drivers/pci/controller/dwc/pci-dra7xx.c
> +++ b/drivers/pci/controller/dwc/pci-dra7xx.c
> @@ -467,6 +467,13 @@ static int dra7xx_add_pcie_ep(struct dra7xx_pcie *dra7xx,
>  		return ret;
>  	}
>  
> +	ret = dw_pcie_ep_init_registers(ep);
> +	if (ret) {
> +		dev_err(dev, "Failed to initialize DWC endpoint registers\n");
> +		dw_pcie_ep_deinit(ep);
> +		return ret;
> +	}
> +
>  	return 0;
>  }
>  
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
> index dc2c036ab28c..bfcafa440ddb 100644
> --- a/drivers/pci/controller/dwc/pci-imx6.c
> +++ b/drivers/pci/controller/dwc/pci-imx6.c
> @@ -1136,6 +1136,14 @@ static int imx6_add_pcie_ep(struct imx6_pcie *imx6_pcie,
>  		dev_err(dev, "failed to initialize endpoint\n");
>  		return ret;
>  	}
> +
> +	ret = dw_pcie_ep_init_registers(ep);
> +	if (ret) {
> +		dev_err(dev, "Failed to initialize DWC endpoint registers\n");
> +		dw_pcie_ep_deinit(ep);
> +		return ret;
> +	}
> +
>  	/* Start LTSSM. */
>  	imx6_pcie_ltssm_enable(dev);
>  
> diff --git a/drivers/pci/controller/dwc/pci-keystone.c b/drivers/pci/controller/dwc/pci-keystone.c
> index c0c62533a3f1..8392894ed286 100644
> --- a/drivers/pci/controller/dwc/pci-keystone.c
> +++ b/drivers/pci/controller/dwc/pci-keystone.c
> @@ -1286,6 +1286,13 @@ static int ks_pcie_probe(struct platform_device *pdev)
>  		ret = dw_pcie_ep_init(&pci->ep);
>  		if (ret < 0)
>  			goto err_get_sync;
> +
> +		ret = dw_pcie_ep_init_registers(&pci->ep);
> +		if (ret < 0) {
> +			dev_err(dev, "Failed to initialize DWC endpoint registers\n");
> +			goto err_ep_init;
> +		}
> +
>  		break;
>  	default:
>  		dev_err(dev, "INVALID device type %d\n", mode);
> @@ -1295,6 +1302,8 @@ static int ks_pcie_probe(struct platform_device *pdev)
>  
>  	return 0;
>  
> +err_ep_init:
> +	dw_pcie_ep_deinit(&pci->ep);
>  err_get_sync:
>  	pm_runtime_put(dev);
>  	pm_runtime_disable(dev);
> diff --git a/drivers/pci/controller/dwc/pci-layerscape-ep.c b/drivers/pci/controller/dwc/pci-layerscape-ep.c
> index 2e398494e7c0..b712fdd06549 100644
> --- a/drivers/pci/controller/dwc/pci-layerscape-ep.c
> +++ b/drivers/pci/controller/dwc/pci-layerscape-ep.c
> @@ -276,6 +276,13 @@ static int __init ls_pcie_ep_probe(struct platform_device *pdev)
>  	if (ret)
>  		return ret;
>  
> +	ret = dw_pcie_ep_init_registers(&pci->ep);
> +	if (ret) {
> +		dev_err(dev, "Failed to initialize DWC endpoint registers\n");
> +		dw_pcie_ep_deinit(&pci->ep);
> +		return ret;
> +	}
> +
>  	return ls_pcie_ep_interrupt_init(pcie, pdev);
>  }
>  
> diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
> index ed1f2afd830a..278bdc9b2269 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-ep.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
> @@ -729,7 +729,6 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
>  	struct device *dev = pci->dev;
>  	struct platform_device *pdev = to_platform_device(dev);
>  	struct device_node *np = dev->of_node;
> -	const struct pci_epc_features *epc_features;
>  
>  	INIT_LIST_HEAD(&ep->func_list);
>  
> @@ -775,29 +774,8 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
>  		goto err_exit_epc_mem;
>  	}
>  
> -	if (ep->ops->get_features) {
> -		epc_features = ep->ops->get_features(ep);
> -		if (epc_features->core_init_notifier)
> -			return 0;
> -	}

why remove this check?

Frank

> -
> -	/*
> -	 * NOTE:- Avoid accessing the hardware (Ex:- DBI space) before this
> -	 * step as platforms that implement 'core_init_notifier' feature may
> -	 * not have the hardware ready (i.e. core initialized) for access
> -	 * (Ex: tegra194). Any hardware access on such platforms result
> -	 * in system hang.
> -	 */
> -	ret = dw_pcie_ep_init_registers(ep);
> -	if (ret)
> -		goto err_free_epc_mem;
> -
>  	return 0;
>  
> -err_free_epc_mem:
> -	pci_epc_mem_free_addr(epc, ep->msi_mem_phys, ep->msi_mem,
> -			      epc->mem->window.page_size);
> -
>  err_exit_epc_mem:
>  	pci_epc_mem_exit(epc);
>  
> diff --git a/drivers/pci/controller/dwc/pcie-designware-plat.c b/drivers/pci/controller/dwc/pcie-designware-plat.c
> index 778588b4be70..ca9b22e654cd 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-plat.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-plat.c
> @@ -145,6 +145,15 @@ static int dw_plat_pcie_probe(struct platform_device *pdev)
>  
>  		pci->ep.ops = &pcie_ep_ops;
>  		ret = dw_pcie_ep_init(&pci->ep);
> +		if (ret)
> +			return ret;
> +
> +		ret = dw_pcie_ep_init_registers(&pci->ep);
> +		if (ret) {
> +			dev_err(dev, "Failed to initialize DWC endpoint registers\n");
> +			dw_pcie_ep_deinit(&pci->ep);
> +		}
> +
>  		break;
>  	default:
>  		dev_err(dev, "INVALID device type %d\n", dw_plat_pcie->mode);
> diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> index 9d9d22e367bb..fb7c03639a53 100644
> --- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> @@ -414,6 +414,7 @@ static const struct dw_pcie_ep_ops pcie_ep_ops = {
>  static int rcar_gen4_add_dw_pcie_ep(struct rcar_gen4_pcie *rcar)
>  {
>  	struct dw_pcie_ep *ep = &rcar->dw.ep;
> +	struct device *dev = rcar->dw.dev;
>  	int ret;
>  
>  	if (!IS_ENABLED(CONFIG_PCIE_RCAR_GEN4_EP))
> @@ -422,8 +423,17 @@ static int rcar_gen4_add_dw_pcie_ep(struct rcar_gen4_pcie *rcar)
>  	ep->ops = &pcie_ep_ops;
>  
>  	ret = dw_pcie_ep_init(ep);
> -	if (ret)
> +	if (ret) {
>  		rcar_gen4_pcie_ep_deinit(rcar);
> +		return ret;
> +	}
> +
> +	ret = dw_pcie_ep_init_registers(ep);
> +	if (ret) {
> +		dev_err(dev, "Failed to initialize DWC endpoint registers\n");
> +		dw_pcie_ep_deinit(ep);
> +		rcar_gen4_pcie_ep_deinit(rcar);
> +	}
>  
>  	return ret;
>  }
> diff --git a/drivers/pci/controller/dwc/pcie-uniphier-ep.c b/drivers/pci/controller/dwc/pcie-uniphier-ep.c
> index 3fced0d3e851..82ccaea089be 100644
> --- a/drivers/pci/controller/dwc/pcie-uniphier-ep.c
> +++ b/drivers/pci/controller/dwc/pcie-uniphier-ep.c
> @@ -399,7 +399,18 @@ static int uniphier_pcie_ep_probe(struct platform_device *pdev)
>  		return ret;
>  
>  	priv->pci.ep.ops = &uniphier_pcie_ep_ops;
> -	return dw_pcie_ep_init(&priv->pci.ep);
> +	ret = dw_pcie_ep_init(&priv->pci.ep);
> +	if (ret)
> +		return ret;
> +
> +	ret = dw_pcie_ep_init_registers(&priv->pci.ep);
> +	if (ret) {
> +		dev_err(dev, "Failed to initialize DWC endpoint registers\n");
> +		dw_pcie_ep_deinit(&priv->pci.ep);
> +		return ret;
> +	}
> +
> +	return 0;
>  }
>  
>  static const struct uniphier_pcie_ep_soc_data uniphier_pro5_data = {
> 
> -- 
> 2.25.1
>
Manivannan Sadhasivam Feb. 27, 2024, 12:21 p.m. UTC | #2
On Mon, Feb 26, 2024 at 12:04:33PM -0500, Frank Li wrote:
> On Sat, Feb 24, 2024 at 12:24:12PM +0530, Manivannan Sadhasivam wrote:
> > Currently, dw_pcie_ep_init_registers() API is directly called by the glue
> > drivers requiring active refclk from host. But for the other drivers, it is
> > getting called implicitly by dw_pcie_ep_init(). This is due to the fact
> > that this API initializes DWC EP specific registers and that requires an
> > active refclk (either from host or generated locally by endpoint itsef).
> > 
> > But, this causes a discrepancy among the glue drivers. So to avoid this
> > confusion, let's call this API directly from all glue drivers irrespective
> > of refclk dependency. Only difference here is that the drivers requiring
> > refclk from host will call this API only after the refclk is received and
> > other drivers without refclk dependency will call this API right after
> > dw_pcie_ep_init().
> > 
> > This change will also allow us to remove the "core_init_notifier" flag in
> > the later commits.
> > 
> > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> > ---
> >  drivers/pci/controller/dwc/pci-dra7xx.c           |  7 +++++++
> >  drivers/pci/controller/dwc/pci-imx6.c             |  8 ++++++++
> >  drivers/pci/controller/dwc/pci-keystone.c         |  9 +++++++++
> >  drivers/pci/controller/dwc/pci-layerscape-ep.c    |  7 +++++++
> >  drivers/pci/controller/dwc/pcie-designware-ep.c   | 22 ----------------------
> >  drivers/pci/controller/dwc/pcie-designware-plat.c |  9 +++++++++
> >  drivers/pci/controller/dwc/pcie-rcar-gen4.c       | 12 +++++++++++-
> >  drivers/pci/controller/dwc/pcie-uniphier-ep.c     | 13 ++++++++++++-
> >  8 files changed, 63 insertions(+), 24 deletions(-)

[...]

> > diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
> > index ed1f2afd830a..278bdc9b2269 100644
> > --- a/drivers/pci/controller/dwc/pcie-designware-ep.c
> > +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
> > @@ -729,7 +729,6 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
> >  	struct device *dev = pci->dev;
> >  	struct platform_device *pdev = to_platform_device(dev);
> >  	struct device_node *np = dev->of_node;
> > -	const struct pci_epc_features *epc_features;
> >  
> >  	INIT_LIST_HEAD(&ep->func_list);
> >  
> > @@ -775,29 +774,8 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
> >  		goto err_exit_epc_mem;
> >  	}
> >  
> > -	if (ep->ops->get_features) {
> > -		epc_features = ep->ops->get_features(ep);
> > -		if (epc_features->core_init_notifier)
> > -			return 0;
> > -	}
> 
> why remove this check?
> 

There is no point in keeping this check since we are removing the call to
dw_pcie_ep_init_registers() below. But I should've described this change in the
commit message.

- Mani
Frank Li Feb. 27, 2024, 5:28 p.m. UTC | #3
On Tue, Feb 27, 2024 at 05:51:41PM +0530, Manivannan Sadhasivam wrote:
> On Mon, Feb 26, 2024 at 12:04:33PM -0500, Frank Li wrote:
> > On Sat, Feb 24, 2024 at 12:24:12PM +0530, Manivannan Sadhasivam wrote:
> > > Currently, dw_pcie_ep_init_registers() API is directly called by the glue
> > > drivers requiring active refclk from host. But for the other drivers, it is
> > > getting called implicitly by dw_pcie_ep_init(). This is due to the fact
> > > that this API initializes DWC EP specific registers and that requires an
> > > active refclk (either from host or generated locally by endpoint itsef).
> > > 
> > > But, this causes a discrepancy among the glue drivers. So to avoid this
> > > confusion, let's call this API directly from all glue drivers irrespective
> > > of refclk dependency. Only difference here is that the drivers requiring
> > > refclk from host will call this API only after the refclk is received and
> > > other drivers without refclk dependency will call this API right after
> > > dw_pcie_ep_init().
> > > 
> > > This change will also allow us to remove the "core_init_notifier" flag in
> > > the later commits.
> > > 
> > > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> > > ---
> > >  drivers/pci/controller/dwc/pci-dra7xx.c           |  7 +++++++
> > >  drivers/pci/controller/dwc/pci-imx6.c             |  8 ++++++++
> > >  drivers/pci/controller/dwc/pci-keystone.c         |  9 +++++++++
> > >  drivers/pci/controller/dwc/pci-layerscape-ep.c    |  7 +++++++
> > >  drivers/pci/controller/dwc/pcie-designware-ep.c   | 22 ----------------------
> > >  drivers/pci/controller/dwc/pcie-designware-plat.c |  9 +++++++++
> > >  drivers/pci/controller/dwc/pcie-rcar-gen4.c       | 12 +++++++++++-
> > >  drivers/pci/controller/dwc/pcie-uniphier-ep.c     | 13 ++++++++++++-
> > >  8 files changed, 63 insertions(+), 24 deletions(-)
> 
> [...]
> 
> > > diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
> > > index ed1f2afd830a..278bdc9b2269 100644
> > > --- a/drivers/pci/controller/dwc/pcie-designware-ep.c
> > > +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
> > > @@ -729,7 +729,6 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
> > >  	struct device *dev = pci->dev;
> > >  	struct platform_device *pdev = to_platform_device(dev);
> > >  	struct device_node *np = dev->of_node;
> > > -	const struct pci_epc_features *epc_features;
> > >  
> > >  	INIT_LIST_HEAD(&ep->func_list);
> > >  
> > > @@ -775,29 +774,8 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
> > >  		goto err_exit_epc_mem;
> > >  	}
> > >  
> > > -	if (ep->ops->get_features) {
> > > -		epc_features = ep->ops->get_features(ep);
> > > -		if (epc_features->core_init_notifier)
> > > -			return 0;
> > > -	}
> > 
> > why remove this check?
> > 
> 
> There is no point in keeping this check since we are removing the call to
> dw_pcie_ep_init_registers() below. But I should've described this change in the
> commit message.

Sperated patch will be helpful. This clean up does not related with other
change.

Frank

> 
> - Mani
> 
> -- 
> மணிவண்ணன் சதாசிவம்
Manivannan Sadhasivam Feb. 27, 2024, 6:42 p.m. UTC | #4
On Tue, Feb 27, 2024 at 12:28:41PM -0500, Frank Li wrote:
> On Tue, Feb 27, 2024 at 05:51:41PM +0530, Manivannan Sadhasivam wrote:
> > On Mon, Feb 26, 2024 at 12:04:33PM -0500, Frank Li wrote:
> > > On Sat, Feb 24, 2024 at 12:24:12PM +0530, Manivannan Sadhasivam wrote:
> > > > Currently, dw_pcie_ep_init_registers() API is directly called by the glue
> > > > drivers requiring active refclk from host. But for the other drivers, it is
> > > > getting called implicitly by dw_pcie_ep_init(). This is due to the fact
> > > > that this API initializes DWC EP specific registers and that requires an
> > > > active refclk (either from host or generated locally by endpoint itsef).
> > > > 
> > > > But, this causes a discrepancy among the glue drivers. So to avoid this
> > > > confusion, let's call this API directly from all glue drivers irrespective
> > > > of refclk dependency. Only difference here is that the drivers requiring
> > > > refclk from host will call this API only after the refclk is received and
> > > > other drivers without refclk dependency will call this API right after
> > > > dw_pcie_ep_init().
> > > > 
> > > > This change will also allow us to remove the "core_init_notifier" flag in
> > > > the later commits.
> > > > 
> > > > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> > > > ---
> > > >  drivers/pci/controller/dwc/pci-dra7xx.c           |  7 +++++++
> > > >  drivers/pci/controller/dwc/pci-imx6.c             |  8 ++++++++
> > > >  drivers/pci/controller/dwc/pci-keystone.c         |  9 +++++++++
> > > >  drivers/pci/controller/dwc/pci-layerscape-ep.c    |  7 +++++++
> > > >  drivers/pci/controller/dwc/pcie-designware-ep.c   | 22 ----------------------
> > > >  drivers/pci/controller/dwc/pcie-designware-plat.c |  9 +++++++++
> > > >  drivers/pci/controller/dwc/pcie-rcar-gen4.c       | 12 +++++++++++-
> > > >  drivers/pci/controller/dwc/pcie-uniphier-ep.c     | 13 ++++++++++++-
> > > >  8 files changed, 63 insertions(+), 24 deletions(-)
> > 
> > [...]
> > 
> > > > diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
> > > > index ed1f2afd830a..278bdc9b2269 100644
> > > > --- a/drivers/pci/controller/dwc/pcie-designware-ep.c
> > > > +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
> > > > @@ -729,7 +729,6 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
> > > >  	struct device *dev = pci->dev;
> > > >  	struct platform_device *pdev = to_platform_device(dev);
> > > >  	struct device_node *np = dev->of_node;
> > > > -	const struct pci_epc_features *epc_features;
> > > >  
> > > >  	INIT_LIST_HEAD(&ep->func_list);
> > > >  
> > > > @@ -775,29 +774,8 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep)
> > > >  		goto err_exit_epc_mem;
> > > >  	}
> > > >  
> > > > -	if (ep->ops->get_features) {
> > > > -		epc_features = ep->ops->get_features(ep);
> > > > -		if (epc_features->core_init_notifier)
> > > > -			return 0;
> > > > -	}
> > > 
> > > why remove this check?
> > > 
> > 
> > There is no point in keeping this check since we are removing the call to
> > dw_pcie_ep_init_registers() below. But I should've described this change in the
> > commit message.
> 
> Sperated patch will be helpful. This clean up does not related with other
> change.
> 

Well this is not a generic cleanup that could be moved to a separate patch. Due
to the changes in this patch, the use of the flag becomes redundant. So it has
to removed here itself.

- Mani
diff mbox series

Patch

diff --git a/drivers/pci/controller/dwc/pci-dra7xx.c b/drivers/pci/controller/dwc/pci-dra7xx.c
index 0e406677060d..395042b29ffc 100644
--- a/drivers/pci/controller/dwc/pci-dra7xx.c
+++ b/drivers/pci/controller/dwc/pci-dra7xx.c
@@ -467,6 +467,13 @@  static int dra7xx_add_pcie_ep(struct dra7xx_pcie *dra7xx,
 		return ret;
 	}
 
+	ret = dw_pcie_ep_init_registers(ep);
+	if (ret) {
+		dev_err(dev, "Failed to initialize DWC endpoint registers\n");
+		dw_pcie_ep_deinit(ep);
+		return ret;
+	}
+
 	return 0;
 }
 
diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
index dc2c036ab28c..bfcafa440ddb 100644
--- a/drivers/pci/controller/dwc/pci-imx6.c
+++ b/drivers/pci/controller/dwc/pci-imx6.c
@@ -1136,6 +1136,14 @@  static int imx6_add_pcie_ep(struct imx6_pcie *imx6_pcie,
 		dev_err(dev, "failed to initialize endpoint\n");
 		return ret;
 	}
+
+	ret = dw_pcie_ep_init_registers(ep);
+	if (ret) {
+		dev_err(dev, "Failed to initialize DWC endpoint registers\n");
+		dw_pcie_ep_deinit(ep);
+		return ret;
+	}
+
 	/* Start LTSSM. */
 	imx6_pcie_ltssm_enable(dev);
 
diff --git a/drivers/pci/controller/dwc/pci-keystone.c b/drivers/pci/controller/dwc/pci-keystone.c
index c0c62533a3f1..8392894ed286 100644
--- a/drivers/pci/controller/dwc/pci-keystone.c
+++ b/drivers/pci/controller/dwc/pci-keystone.c
@@ -1286,6 +1286,13 @@  static int ks_pcie_probe(struct platform_device *pdev)
 		ret = dw_pcie_ep_init(&pci->ep);
 		if (ret < 0)
 			goto err_get_sync;
+
+		ret = dw_pcie_ep_init_registers(&pci->ep);
+		if (ret < 0) {
+			dev_err(dev, "Failed to initialize DWC endpoint registers\n");
+			goto err_ep_init;
+		}
+
 		break;
 	default:
 		dev_err(dev, "INVALID device type %d\n", mode);
@@ -1295,6 +1302,8 @@  static int ks_pcie_probe(struct platform_device *pdev)
 
 	return 0;
 
+err_ep_init:
+	dw_pcie_ep_deinit(&pci->ep);
 err_get_sync:
 	pm_runtime_put(dev);
 	pm_runtime_disable(dev);
diff --git a/drivers/pci/controller/dwc/pci-layerscape-ep.c b/drivers/pci/controller/dwc/pci-layerscape-ep.c
index 2e398494e7c0..b712fdd06549 100644
--- a/drivers/pci/controller/dwc/pci-layerscape-ep.c
+++ b/drivers/pci/controller/dwc/pci-layerscape-ep.c
@@ -276,6 +276,13 @@  static int __init ls_pcie_ep_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
+	ret = dw_pcie_ep_init_registers(&pci->ep);
+	if (ret) {
+		dev_err(dev, "Failed to initialize DWC endpoint registers\n");
+		dw_pcie_ep_deinit(&pci->ep);
+		return ret;
+	}
+
 	return ls_pcie_ep_interrupt_init(pcie, pdev);
 }
 
diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
index ed1f2afd830a..278bdc9b2269 100644
--- a/drivers/pci/controller/dwc/pcie-designware-ep.c
+++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
@@ -729,7 +729,6 @@  int dw_pcie_ep_init(struct dw_pcie_ep *ep)
 	struct device *dev = pci->dev;
 	struct platform_device *pdev = to_platform_device(dev);
 	struct device_node *np = dev->of_node;
-	const struct pci_epc_features *epc_features;
 
 	INIT_LIST_HEAD(&ep->func_list);
 
@@ -775,29 +774,8 @@  int dw_pcie_ep_init(struct dw_pcie_ep *ep)
 		goto err_exit_epc_mem;
 	}
 
-	if (ep->ops->get_features) {
-		epc_features = ep->ops->get_features(ep);
-		if (epc_features->core_init_notifier)
-			return 0;
-	}
-
-	/*
-	 * NOTE:- Avoid accessing the hardware (Ex:- DBI space) before this
-	 * step as platforms that implement 'core_init_notifier' feature may
-	 * not have the hardware ready (i.e. core initialized) for access
-	 * (Ex: tegra194). Any hardware access on such platforms result
-	 * in system hang.
-	 */
-	ret = dw_pcie_ep_init_registers(ep);
-	if (ret)
-		goto err_free_epc_mem;
-
 	return 0;
 
-err_free_epc_mem:
-	pci_epc_mem_free_addr(epc, ep->msi_mem_phys, ep->msi_mem,
-			      epc->mem->window.page_size);
-
 err_exit_epc_mem:
 	pci_epc_mem_exit(epc);
 
diff --git a/drivers/pci/controller/dwc/pcie-designware-plat.c b/drivers/pci/controller/dwc/pcie-designware-plat.c
index 778588b4be70..ca9b22e654cd 100644
--- a/drivers/pci/controller/dwc/pcie-designware-plat.c
+++ b/drivers/pci/controller/dwc/pcie-designware-plat.c
@@ -145,6 +145,15 @@  static int dw_plat_pcie_probe(struct platform_device *pdev)
 
 		pci->ep.ops = &pcie_ep_ops;
 		ret = dw_pcie_ep_init(&pci->ep);
+		if (ret)
+			return ret;
+
+		ret = dw_pcie_ep_init_registers(&pci->ep);
+		if (ret) {
+			dev_err(dev, "Failed to initialize DWC endpoint registers\n");
+			dw_pcie_ep_deinit(&pci->ep);
+		}
+
 		break;
 	default:
 		dev_err(dev, "INVALID device type %d\n", dw_plat_pcie->mode);
diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
index 9d9d22e367bb..fb7c03639a53 100644
--- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
+++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
@@ -414,6 +414,7 @@  static const struct dw_pcie_ep_ops pcie_ep_ops = {
 static int rcar_gen4_add_dw_pcie_ep(struct rcar_gen4_pcie *rcar)
 {
 	struct dw_pcie_ep *ep = &rcar->dw.ep;
+	struct device *dev = rcar->dw.dev;
 	int ret;
 
 	if (!IS_ENABLED(CONFIG_PCIE_RCAR_GEN4_EP))
@@ -422,8 +423,17 @@  static int rcar_gen4_add_dw_pcie_ep(struct rcar_gen4_pcie *rcar)
 	ep->ops = &pcie_ep_ops;
 
 	ret = dw_pcie_ep_init(ep);
-	if (ret)
+	if (ret) {
 		rcar_gen4_pcie_ep_deinit(rcar);
+		return ret;
+	}
+
+	ret = dw_pcie_ep_init_registers(ep);
+	if (ret) {
+		dev_err(dev, "Failed to initialize DWC endpoint registers\n");
+		dw_pcie_ep_deinit(ep);
+		rcar_gen4_pcie_ep_deinit(rcar);
+	}
 
 	return ret;
 }
diff --git a/drivers/pci/controller/dwc/pcie-uniphier-ep.c b/drivers/pci/controller/dwc/pcie-uniphier-ep.c
index 3fced0d3e851..82ccaea089be 100644
--- a/drivers/pci/controller/dwc/pcie-uniphier-ep.c
+++ b/drivers/pci/controller/dwc/pcie-uniphier-ep.c
@@ -399,7 +399,18 @@  static int uniphier_pcie_ep_probe(struct platform_device *pdev)
 		return ret;
 
 	priv->pci.ep.ops = &uniphier_pcie_ep_ops;
-	return dw_pcie_ep_init(&priv->pci.ep);
+	ret = dw_pcie_ep_init(&priv->pci.ep);
+	if (ret)
+		return ret;
+
+	ret = dw_pcie_ep_init_registers(&priv->pci.ep);
+	if (ret) {
+		dev_err(dev, "Failed to initialize DWC endpoint registers\n");
+		dw_pcie_ep_deinit(&priv->pci.ep);
+		return ret;
+	}
+
+	return 0;
 }
 
 static const struct uniphier_pcie_ep_soc_data uniphier_pro5_data = {