diff mbox series

[v2,13/15] PCI: cadence: add resume support to cdns_pcie_host_setup()

Message ID 20240102-j7200-pcie-s2r-v2-13-8e4f7d228ec2@bootlin.com (mailing list archive)
State New, archived
Headers show
Series Add suspend to ram support for PCIe on J7200 | expand

Commit Message

Thomas Richard Jan. 26, 2024, 2:36 p.m. UTC
From: Théo Lebrun <theo.lebrun@bootlin.com>

That function mixes probe structure init and hardware config.
The whole hardware config part must be done at resume after a suspend to
ram.
We therefore pass it a boolean flag determining if we are at probe or at
resume.

Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
---
 drivers/pci/controller/cadence/pci-j721e.c         |  2 +-
 drivers/pci/controller/cadence/pcie-cadence-host.c | 49 ++++++++++++----------
 drivers/pci/controller/cadence/pcie-cadence-plat.c |  2 +-
 drivers/pci/controller/cadence/pcie-cadence.h      |  4 +-
 4 files changed, 30 insertions(+), 27 deletions(-)

Comments

Bjorn Helgaas Jan. 26, 2024, 9:43 p.m. UTC | #1
In subject, capitalize "Add ..." to follow historical convention.
Also the other driver/pci/ patches.

On Fri, Jan 26, 2024 at 03:36:55PM +0100, Thomas Richard wrote:
> From: Théo Lebrun <theo.lebrun@bootlin.com>
> 
> That function mixes probe structure init and hardware config.
> The whole hardware config part must be done at resume after a suspend to
> ram.
> We therefore pass it a boolean flag determining if we are at probe or at
> resume.

s/That function/cdns_pcie_host_setup()/ so the commit log stands
alone even without the subject line.

s/ram/RAM/

Add blank line between paragraphs (or rewrap into a single paragraph).

This is pretty similar but slightly different from the DWC pattern:

  imx6_pcie_probe
    ... do structure init ...
    if (RC)
      dw_pcie_host_init
	pp->ops->init
	  imx6_pcie_host_init

  imx6_pcie_resume_noirq
    imx6_pcie_host_init

  j721e_pcie_probe
    j721e_pcie_ctrl_init
    if (RC)
      cdns_pcie_host_setup(true)

  j721e_pcie_resume_noirq
    j721e_pcie_ctrl_init
    if (RC)
      cdns_pcie_host_setup(false)

It'd be super nice to have them the same.  Passing in a "probe" flag
works but seems a little harder to read in cdns_pcie_host_setup() and
you have to keep track of what it means in the callers.

> Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
> Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
> ---
>  drivers/pci/controller/cadence/pci-j721e.c         |  2 +-
>  drivers/pci/controller/cadence/pcie-cadence-host.c | 49 ++++++++++++----------
>  drivers/pci/controller/cadence/pcie-cadence-plat.c |  2 +-
>  drivers/pci/controller/cadence/pcie-cadence.h      |  4 +-
>  4 files changed, 30 insertions(+), 27 deletions(-)
> 
> diff --git a/drivers/pci/controller/cadence/pci-j721e.c b/drivers/pci/controller/cadence/pci-j721e.c
> index 2c87e7728a65..9b343a46da11 100644
> --- a/drivers/pci/controller/cadence/pci-j721e.c
> +++ b/drivers/pci/controller/cadence/pci-j721e.c
> @@ -509,7 +509,7 @@ static int j721e_pcie_probe(struct platform_device *pdev)
>  			gpiod_set_value_cansleep(gpiod, 1);
>  		}
>  
> -		ret = cdns_pcie_host_setup(rc);
> +		ret = cdns_pcie_host_setup(rc, true);
>  		if (ret < 0) {
>  			clk_disable_unprepare(pcie->refclk);
>  			goto err_pcie_setup;
> diff --git a/drivers/pci/controller/cadence/pcie-cadence-host.c b/drivers/pci/controller/cadence/pcie-cadence-host.c
> index 5b14f7ee3c79..dd4d876a9138 100644
> --- a/drivers/pci/controller/cadence/pcie-cadence-host.c
> +++ b/drivers/pci/controller/cadence/pcie-cadence-host.c
> @@ -497,14 +497,14 @@ static int cdns_pcie_host_init(struct device *dev,
>  	return cdns_pcie_host_init_address_translation(rc);
>  }
>  
> -int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
> +int cdns_pcie_host_setup(struct cdns_pcie_rc *rc, bool probe)
>  {
>  	struct device *dev = rc->pcie.dev;
>  	struct platform_device *pdev = to_platform_device(dev);
>  	struct device_node *np = dev->of_node;
>  	struct pci_host_bridge *bridge;
>  	enum cdns_pcie_rp_bar bar;
> -	struct cdns_pcie *pcie;
> +	struct cdns_pcie *pcie = &rc->pcie;
>  	struct resource *res;
>  	int ret;
>  
> @@ -512,26 +512,27 @@ int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
>  	if (!bridge)
>  		return -ENOMEM;
>  
> -	pcie = &rc->pcie;
> -	pcie->is_rc = true;
> +	if (probe) {
> +		pcie->is_rc = true;
>  
> -	rc->vendor_id = 0xffff;
> -	of_property_read_u32(np, "vendor-id", &rc->vendor_id);
> +		rc->vendor_id = 0xffff;
> +		of_property_read_u32(np, "vendor-id", &rc->vendor_id);
>  
> -	rc->device_id = 0xffff;
> -	of_property_read_u32(np, "device-id", &rc->device_id);
> +		rc->device_id = 0xffff;
> +		of_property_read_u32(np, "device-id", &rc->device_id);
>  
> -	pcie->reg_base = devm_platform_ioremap_resource_byname(pdev, "reg");
> -	if (IS_ERR(pcie->reg_base)) {
> -		dev_err(dev, "missing \"reg\"\n");
> -		return PTR_ERR(pcie->reg_base);
> -	}
> +		pcie->reg_base = devm_platform_ioremap_resource_byname(pdev, "reg");
> +		if (IS_ERR(pcie->reg_base)) {
> +			dev_err(dev, "missing \"reg\"\n");
> +			return PTR_ERR(pcie->reg_base);
> +		}
>  
> -	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
> -	rc->cfg_base = devm_pci_remap_cfg_resource(dev, res);
> -	if (IS_ERR(rc->cfg_base))
> -		return PTR_ERR(rc->cfg_base);
> -	rc->cfg_res = res;
> +		res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
> +		rc->cfg_base = devm_pci_remap_cfg_resource(dev, res);
> +		if (IS_ERR(rc->cfg_base))
> +			return PTR_ERR(rc->cfg_base);
> +		rc->cfg_res = res;
> +	}
>  
>  	if (rc->quirk_detect_quiet_flag)
>  		cdns_pcie_detect_quiet_min_delay_set(&rc->pcie);
> @@ -555,12 +556,14 @@ int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
>  	if (ret)
>  		return ret;
>  
> -	if (!bridge->ops)
> -		bridge->ops = &cdns_pcie_host_ops;
> +	if (probe) {
> +		if (!bridge->ops)
> +			bridge->ops = &cdns_pcie_host_ops;
>  
> -	ret = pci_host_probe(bridge);
> -	if (ret < 0)
> -		goto err_init;
> +		ret = pci_host_probe(bridge);
> +		if (ret < 0)
> +			goto err_init;
> +	}
>  
>  	return 0;
>  
> diff --git a/drivers/pci/controller/cadence/pcie-cadence-plat.c b/drivers/pci/controller/cadence/pcie-cadence-plat.c
> index 0456845dabb9..071423091668 100644
> --- a/drivers/pci/controller/cadence/pcie-cadence-plat.c
> +++ b/drivers/pci/controller/cadence/pcie-cadence-plat.c
> @@ -86,7 +86,7 @@ static int cdns_plat_pcie_probe(struct platform_device *pdev)
>  			goto err_get_sync;
>  		}
>  
> -		ret = cdns_pcie_host_setup(rc);
> +		ret = cdns_pcie_host_setup(rc, true);
>  		if (ret)
>  			goto err_init;
>  	} else {
> diff --git a/drivers/pci/controller/cadence/pcie-cadence.h b/drivers/pci/controller/cadence/pcie-cadence.h
> index 373cb50fcd15..3b0da889ed64 100644
> --- a/drivers/pci/controller/cadence/pcie-cadence.h
> +++ b/drivers/pci/controller/cadence/pcie-cadence.h
> @@ -515,11 +515,11 @@ static inline bool cdns_pcie_link_up(struct cdns_pcie *pcie)
>  }
>  
>  #ifdef CONFIG_PCIE_CADENCE_HOST
> -int cdns_pcie_host_setup(struct cdns_pcie_rc *rc);
> +int cdns_pcie_host_setup(struct cdns_pcie_rc *rc, bool probe);
>  void __iomem *cdns_pci_map_bus(struct pci_bus *bus, unsigned int devfn,
>  			       int where);
>  #else
> -static inline int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
> +static inline int cdns_pcie_host_setup(struct cdns_pcie_rc *rc, bool probe)
>  {
>  	return 0;
>  }
> 
> -- 
> 2.39.2
>
Andy Shevchenko Jan. 26, 2024, 9:50 p.m. UTC | #2
On Fri, Jan 26, 2024 at 11:43 PM Bjorn Helgaas <helgaas@kernel.org> wrote:
> On Fri, Jan 26, 2024 at 03:36:55PM +0100, Thomas Richard wrote:

...

> It'd be super nice to have them the same.  Passing in a "probe" flag
> works but seems a little harder to read in cdns_pcie_host_setup() and
> you have to keep track of what it means in the callers.

FWIW, in another patch with a similar approach I found it (the
approach) a bit ugly and unmaintainable. I would suggest properly
refactoring to create 2+ functions and use as needed.
Bjorn Helgaas Jan. 29, 2024, 10:16 p.m. UTC | #3
On Fri, Jan 26, 2024 at 03:43:39PM -0600, Bjorn Helgaas wrote:
> In subject, capitalize "Add ..." to follow historical convention.
> Also the other driver/pci/ patches.
> 
> On Fri, Jan 26, 2024 at 03:36:55PM +0100, Thomas Richard wrote:
> > From: Théo Lebrun <theo.lebrun@bootlin.com>
> > 
> > That function mixes probe structure init and hardware config.
> > The whole hardware config part must be done at resume after a suspend to
> > ram.
> > We therefore pass it a boolean flag determining if we are at probe or at
> > resume.
> ...

> This is pretty similar but slightly different from the DWC pattern:
> 
>   imx6_pcie_probe
>     ... do structure init ...
>     if (RC)
>       dw_pcie_host_init
> 	pp->ops->init
> 	  imx6_pcie_host_init
> 
>   imx6_pcie_resume_noirq
>     imx6_pcie_host_init
> 
>   j721e_pcie_probe
>     j721e_pcie_ctrl_init
>     if (RC)
>       cdns_pcie_host_setup(true)
> 
>   j721e_pcie_resume_noirq
>     j721e_pcie_ctrl_init
>     if (RC)
>       cdns_pcie_host_setup(false)
> 
> It'd be super nice to have them the same.  Passing in a "probe" flag
> works but seems a little harder to read in cdns_pcie_host_setup() and
> you have to keep track of what it means in the callers.

Maybe a better way to say this is that this patch uses the "probe"
flag to select the behavior of cdns_pcie_host_setup(), and I think it
would be nicer to split those two behaviors into separate functions.

Bjorn
Bjorn Helgaas Jan. 29, 2024, 10:24 p.m. UTC | #4
On Mon, Jan 29, 2024 at 04:16:49PM -0600, Bjorn Helgaas wrote:
> On Fri, Jan 26, 2024 at 03:43:39PM -0600, Bjorn Helgaas wrote:
> > On Fri, Jan 26, 2024 at 03:36:55PM +0100, Thomas Richard wrote:
> > > From: Théo Lebrun <theo.lebrun@bootlin.com>
> > > 
> > > That function mixes probe structure init and hardware config.
> > > The whole hardware config part must be done at resume after a suspend to
> > > ram.
> > > We therefore pass it a boolean flag determining if we are at probe or at
> > > resume.
> > ...

> > It'd be super nice to have them the same.  Passing in a "probe" flag
> > works but seems a little harder to read in cdns_pcie_host_setup() and
> > you have to keep track of what it means in the callers.
> 
> Maybe a better way to say this is that this patch uses the "probe"
> flag to select the behavior of cdns_pcie_host_setup(), and I think it
> would be nicer to split those two behaviors into separate functions.

Oops, sorry, Andy, I wrote this before I saw your similar response
from last Friday.  Didn't mean to repeat what you already said!

Bjorn
diff mbox series

Patch

diff --git a/drivers/pci/controller/cadence/pci-j721e.c b/drivers/pci/controller/cadence/pci-j721e.c
index 2c87e7728a65..9b343a46da11 100644
--- a/drivers/pci/controller/cadence/pci-j721e.c
+++ b/drivers/pci/controller/cadence/pci-j721e.c
@@ -509,7 +509,7 @@  static int j721e_pcie_probe(struct platform_device *pdev)
 			gpiod_set_value_cansleep(gpiod, 1);
 		}
 
-		ret = cdns_pcie_host_setup(rc);
+		ret = cdns_pcie_host_setup(rc, true);
 		if (ret < 0) {
 			clk_disable_unprepare(pcie->refclk);
 			goto err_pcie_setup;
diff --git a/drivers/pci/controller/cadence/pcie-cadence-host.c b/drivers/pci/controller/cadence/pcie-cadence-host.c
index 5b14f7ee3c79..dd4d876a9138 100644
--- a/drivers/pci/controller/cadence/pcie-cadence-host.c
+++ b/drivers/pci/controller/cadence/pcie-cadence-host.c
@@ -497,14 +497,14 @@  static int cdns_pcie_host_init(struct device *dev,
 	return cdns_pcie_host_init_address_translation(rc);
 }
 
-int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
+int cdns_pcie_host_setup(struct cdns_pcie_rc *rc, bool probe)
 {
 	struct device *dev = rc->pcie.dev;
 	struct platform_device *pdev = to_platform_device(dev);
 	struct device_node *np = dev->of_node;
 	struct pci_host_bridge *bridge;
 	enum cdns_pcie_rp_bar bar;
-	struct cdns_pcie *pcie;
+	struct cdns_pcie *pcie = &rc->pcie;
 	struct resource *res;
 	int ret;
 
@@ -512,26 +512,27 @@  int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
 	if (!bridge)
 		return -ENOMEM;
 
-	pcie = &rc->pcie;
-	pcie->is_rc = true;
+	if (probe) {
+		pcie->is_rc = true;
 
-	rc->vendor_id = 0xffff;
-	of_property_read_u32(np, "vendor-id", &rc->vendor_id);
+		rc->vendor_id = 0xffff;
+		of_property_read_u32(np, "vendor-id", &rc->vendor_id);
 
-	rc->device_id = 0xffff;
-	of_property_read_u32(np, "device-id", &rc->device_id);
+		rc->device_id = 0xffff;
+		of_property_read_u32(np, "device-id", &rc->device_id);
 
-	pcie->reg_base = devm_platform_ioremap_resource_byname(pdev, "reg");
-	if (IS_ERR(pcie->reg_base)) {
-		dev_err(dev, "missing \"reg\"\n");
-		return PTR_ERR(pcie->reg_base);
-	}
+		pcie->reg_base = devm_platform_ioremap_resource_byname(pdev, "reg");
+		if (IS_ERR(pcie->reg_base)) {
+			dev_err(dev, "missing \"reg\"\n");
+			return PTR_ERR(pcie->reg_base);
+		}
 
-	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
-	rc->cfg_base = devm_pci_remap_cfg_resource(dev, res);
-	if (IS_ERR(rc->cfg_base))
-		return PTR_ERR(rc->cfg_base);
-	rc->cfg_res = res;
+		res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
+		rc->cfg_base = devm_pci_remap_cfg_resource(dev, res);
+		if (IS_ERR(rc->cfg_base))
+			return PTR_ERR(rc->cfg_base);
+		rc->cfg_res = res;
+	}
 
 	if (rc->quirk_detect_quiet_flag)
 		cdns_pcie_detect_quiet_min_delay_set(&rc->pcie);
@@ -555,12 +556,14 @@  int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
 	if (ret)
 		return ret;
 
-	if (!bridge->ops)
-		bridge->ops = &cdns_pcie_host_ops;
+	if (probe) {
+		if (!bridge->ops)
+			bridge->ops = &cdns_pcie_host_ops;
 
-	ret = pci_host_probe(bridge);
-	if (ret < 0)
-		goto err_init;
+		ret = pci_host_probe(bridge);
+		if (ret < 0)
+			goto err_init;
+	}
 
 	return 0;
 
diff --git a/drivers/pci/controller/cadence/pcie-cadence-plat.c b/drivers/pci/controller/cadence/pcie-cadence-plat.c
index 0456845dabb9..071423091668 100644
--- a/drivers/pci/controller/cadence/pcie-cadence-plat.c
+++ b/drivers/pci/controller/cadence/pcie-cadence-plat.c
@@ -86,7 +86,7 @@  static int cdns_plat_pcie_probe(struct platform_device *pdev)
 			goto err_get_sync;
 		}
 
-		ret = cdns_pcie_host_setup(rc);
+		ret = cdns_pcie_host_setup(rc, true);
 		if (ret)
 			goto err_init;
 	} else {
diff --git a/drivers/pci/controller/cadence/pcie-cadence.h b/drivers/pci/controller/cadence/pcie-cadence.h
index 373cb50fcd15..3b0da889ed64 100644
--- a/drivers/pci/controller/cadence/pcie-cadence.h
+++ b/drivers/pci/controller/cadence/pcie-cadence.h
@@ -515,11 +515,11 @@  static inline bool cdns_pcie_link_up(struct cdns_pcie *pcie)
 }
 
 #ifdef CONFIG_PCIE_CADENCE_HOST
-int cdns_pcie_host_setup(struct cdns_pcie_rc *rc);
+int cdns_pcie_host_setup(struct cdns_pcie_rc *rc, bool probe);
 void __iomem *cdns_pci_map_bus(struct pci_bus *bus, unsigned int devfn,
 			       int where);
 #else
-static inline int cdns_pcie_host_setup(struct cdns_pcie_rc *rc)
+static inline int cdns_pcie_host_setup(struct cdns_pcie_rc *rc, bool probe)
 {
 	return 0;
 }