diff mbox series

[2/2] fpga: Add support for Xilinx DFX AXI Shutdown manager

Message ID 20210115013431.27667-2-nava.manne@xilinx.com (mailing list archive)
State Under Review
Headers show
Series [1/2] dt-bindings: fpga: Add compatible value for Xilinx DFX AXI shutdown manger | expand

Commit Message

Nava kishore Manne Jan. 15, 2021, 1:34 a.m. UTC
This patch adds support for Xilinx Dynamic Function eXchange(DFX) AXI
shutdown manager IP. It can be used to safely handling the AXI traffic
on a Reconfigurable Partition when it is undergoing dynamic reconfiguration
and there by preventing system deadlock that may occur if AXI transactions
are interrupted during reconfiguration.

PR-Decoupler and AXI shutdown manager are completely different IPs.
But both the IP registers are compatible and also both belong to the
same sub-system (fpga-bridge).So using same driver for both IP's.

Signed-off-by: Nava kishore Manne <nava.manne@xilinx.com>
---
 drivers/fpga/xilinx-pr-decoupler.c | 35 ++++++++++++++++++++++++++----
 1 file changed, 31 insertions(+), 4 deletions(-)

Comments

Tom Rix Jan. 15, 2021, 6:26 p.m. UTC | #1
On 1/14/21 5:34 PM, Nava kishore Manne wrote:
> This patch adds support for Xilinx Dynamic Function eXchange(DFX) AXI
> shutdown manager IP. It can be used to safely handling the AXI traffic
> on a Reconfigurable Partition when it is undergoing dynamic reconfiguration
> and there by preventing system deadlock that may occur if AXI transactions
> are interrupted during reconfiguration.
>
> PR-Decoupler and AXI shutdown manager are completely different IPs.
> But both the IP registers are compatible and also both belong to the
> same sub-system (fpga-bridge).So using same driver for both IP's.
>
> Signed-off-by: Nava kishore Manne <nava.manne@xilinx.com>
> ---
>  drivers/fpga/xilinx-pr-decoupler.c | 35 ++++++++++++++++++++++++++----

It looks like the copyright is wrong, please review spelling of Xilix

 * Copyright (c) 2017, Xilix Inc


>  1 file changed, 31 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/fpga/xilinx-pr-decoupler.c b/drivers/fpga/xilinx-pr-decoupler.c
> index 7d69af230567..c95f3d065ccb 100644
> --- a/drivers/fpga/xilinx-pr-decoupler.c
> +++ b/drivers/fpga/xilinx-pr-decoupler.c
> @@ -19,10 +19,15 @@
>  #define CTRL_OFFSET		0
>  
>  struct xlnx_pr_decoupler_data {
> +	const struct xlnx_config_data *ipconfig;
>  	void __iomem *io_base;
>  	struct clk *clk;
>  };
>  
> +struct xlnx_config_data {
> +	char *name;
> +};

Move xlnx_config_data above xlnx_pr_decouple_data.

could you 'const' char *name ?

> +
>  static inline void xlnx_pr_decoupler_write(struct xlnx_pr_decoupler_data *d,
>  					   u32 offset, u32 val)
>  {
> @@ -76,15 +81,28 @@ static const struct fpga_bridge_ops xlnx_pr_decoupler_br_ops = {
>  	.enable_show = xlnx_pr_decoupler_enable_show,
>  };
>  
> +static const struct xlnx_config_data decoupler_config = {
> +	.name = "Xilinx PR Decoupler",
> +};
> +
> +static const struct xlnx_config_data shutdown_config = {
> +	.name = "Xilinx DFX AXI shutdown mgr",

To be consistent with decoupler name,

shutdown mgr -> Shutdown Manager

> +};
> +
>  static const struct of_device_id xlnx_pr_decoupler_of_match[] = {
> -	{ .compatible = "xlnx,pr-decoupler-1.00", },
> -	{ .compatible = "xlnx,pr-decoupler", },
> +	{ .compatible = "xlnx,pr-decoupler-1.00", .data = &decoupler_config },
> +	{ .compatible = "xlnx,pr-decoupler", .data = &decoupler_config },
> +	{ .compatible = "xlnx,dfx-axi-shutdown-manager-1.00",
> +					.data = &shutdown_config },
> +	{ .compatible = "xlnx,dfx-axi-shutdown-manager",
> +					.data = &shutdown_config },
>  	{},
>  };
>  MODULE_DEVICE_TABLE(of, xlnx_pr_decoupler_of_match);
>  
>  static int xlnx_pr_decoupler_probe(struct platform_device *pdev)
>  {
> +	struct device_node *np = pdev->dev.of_node;
>  	struct xlnx_pr_decoupler_data *priv;
>  	struct fpga_bridge *br;
>  	int err;
> @@ -94,6 +112,14 @@ static int xlnx_pr_decoupler_probe(struct platform_device *pdev)
>  	if (!priv)
>  		return -ENOMEM;
>  
> +	if (np) {
> +		const struct of_device_id *match;
> +
> +		match = of_match_node(xlnx_pr_decoupler_of_match, np);
> +		if (match && match->data)
> +			priv->ipconfig = match->data;
> +	}
> +
>  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>  	priv->io_base = devm_ioremap_resource(&pdev->dev, res);
>  	if (IS_ERR(priv->io_base))
> @@ -114,7 +140,7 @@ static int xlnx_pr_decoupler_probe(struct platform_device *pdev)
>  
>  	clk_disable(priv->clk);
>  
> -	br = devm_fpga_bridge_create(&pdev->dev, "Xilinx PR Decoupler",
> +	br = devm_fpga_bridge_create(&pdev->dev, priv->ipconfig->name,
>  				     &xlnx_pr_decoupler_br_ops, priv);
>  	if (!br) {
>  		err = -ENOMEM;
> @@ -125,7 +151,8 @@ static int xlnx_pr_decoupler_probe(struct platform_device *pdev)
>  
>  	err = fpga_bridge_register(br);
>  	if (err) {
> -		dev_err(&pdev->dev, "unable to register Xilinx PR Decoupler");
> +		dev_err(&pdev->dev, "unable to register %s",
> +			priv->ipconfig->name);
>  		goto err_clk;
>  	}

Look at XILINX_PR_DECOUPLER entry in Kconfig, maybe add something like

help

  Say Y to enable drivers for the  ... Decoupler or DFX AIX Shutdown Manager

Tom

>
Moritz Fischer Jan. 16, 2021, 2:58 a.m. UTC | #2
Hi,

On Fri, Jan 15, 2021 at 07:04:31AM +0530, Nava kishore Manne wrote:
> This patch adds support for Xilinx Dynamic Function eXchange(DFX) AXI
> shutdown manager IP. It can be used to safely handling the AXI traffic
> on a Reconfigurable Partition when it is undergoing dynamic reconfiguration
> and there by preventing system deadlock that may occur if AXI transactions
> are interrupted during reconfiguration.
> 
> PR-Decoupler and AXI shutdown manager are completely different IPs.
> But both the IP registers are compatible and also both belong to the
> same sub-system (fpga-bridge).So using same driver for both IP's.

I'm a bit confused, the whole goal here is to give the thing a
different name?
> 
> Signed-off-by: Nava kishore Manne <nava.manne@xilinx.com>
> ---
>  drivers/fpga/xilinx-pr-decoupler.c | 35 ++++++++++++++++++++++++++----
>  1 file changed, 31 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/fpga/xilinx-pr-decoupler.c b/drivers/fpga/xilinx-pr-decoupler.c
> index 7d69af230567..c95f3d065ccb 100644
> --- a/drivers/fpga/xilinx-pr-decoupler.c
> +++ b/drivers/fpga/xilinx-pr-decoupler.c
> @@ -19,10 +19,15 @@
>  #define CTRL_OFFSET		0
>  
>  struct xlnx_pr_decoupler_data {
> +	const struct xlnx_config_data *ipconfig;
>  	void __iomem *io_base;
>  	struct clk *clk;
>  };
>  
> +struct xlnx_config_data {
> +	char *name;
> +};
> +
>  static inline void xlnx_pr_decoupler_write(struct xlnx_pr_decoupler_data *d,
>  					   u32 offset, u32 val)
>  {
> @@ -76,15 +81,28 @@ static const struct fpga_bridge_ops xlnx_pr_decoupler_br_ops = {
>  	.enable_show = xlnx_pr_decoupler_enable_show,
>  };
>  
> +static const struct xlnx_config_data decoupler_config = {
> +	.name = "Xilinx PR Decoupler",
> +};
> +
> +static const struct xlnx_config_data shutdown_config = {
> +	.name = "Xilinx DFX AXI shutdown mgr",
> +};

If it's just the strings, why not store them as is?
> +
>  static const struct of_device_id xlnx_pr_decoupler_of_match[] = {
> -	{ .compatible = "xlnx,pr-decoupler-1.00", },
> -	{ .compatible = "xlnx,pr-decoupler", },
> +	{ .compatible = "xlnx,pr-decoupler-1.00", .data = &decoupler_config },
> +	{ .compatible = "xlnx,pr-decoupler", .data = &decoupler_config },
> +	{ .compatible = "xlnx,dfx-axi-shutdown-manager-1.00",
> +					.data = &shutdown_config },
> +	{ .compatible = "xlnx,dfx-axi-shutdown-manager",
> +					.data = &shutdown_config },
>  	{},
>  };
>  MODULE_DEVICE_TABLE(of, xlnx_pr_decoupler_of_match);
>  
>  static int xlnx_pr_decoupler_probe(struct platform_device *pdev)
>  {
> +	struct device_node *np = pdev->dev.of_node;
>  	struct xlnx_pr_decoupler_data *priv;
>  	struct fpga_bridge *br;
>  	int err;
> @@ -94,6 +112,14 @@ static int xlnx_pr_decoupler_probe(struct platform_device *pdev)
>  	if (!priv)
>  		return -ENOMEM;
>  
> +	if (np) {
> +		const struct of_device_id *match;
> +
> +		match = of_match_node(xlnx_pr_decoupler_of_match, np);
> +		if (match && match->data)
> +			priv->ipconfig = match->data;
> +	}
> +
>  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>  	priv->io_base = devm_ioremap_resource(&pdev->dev, res);
>  	if (IS_ERR(priv->io_base))
> @@ -114,7 +140,7 @@ static int xlnx_pr_decoupler_probe(struct platform_device *pdev)
>  
>  	clk_disable(priv->clk);
>  
> -	br = devm_fpga_bridge_create(&pdev->dev, "Xilinx PR Decoupler",
> +	br = devm_fpga_bridge_create(&pdev->dev, priv->ipconfig->name,
>  				     &xlnx_pr_decoupler_br_ops, priv);
>  	if (!br) {
>  		err = -ENOMEM;
> @@ -125,7 +151,8 @@ static int xlnx_pr_decoupler_probe(struct platform_device *pdev)
>  
>  	err = fpga_bridge_register(br);
>  	if (err) {
> -		dev_err(&pdev->dev, "unable to register Xilinx PR Decoupler");
> +		dev_err(&pdev->dev, "unable to register %s",
> +			priv->ipconfig->name);
>  		goto err_clk;
>  	}
>  
> -- 
> 2.18.0
> 

Thanks,
Moritz
Nava kishore Manne Jan. 19, 2021, 6:16 a.m. UTC | #3
Hi Tom,

	Thanks for the review.
Please find my response inline.

> -----Original Message-----
> From: Tom Rix <trix@redhat.com>
> Sent: Friday, January 15, 2021 11:56 PM
> To: Nava kishore Manne <navam@xilinx.com>; mdf@kernel.org;
> robh+dt@kernel.org; Michal Simek <michals@xilinx.com>; linux-
> fpga@vger.kernel.org; devicetree@vger.kernel.org; linux-arm-
> kernel@lists.infradead.org; linux-kernel@vger.kernel.org
> Cc: git <git@xilinx.com>; chinnikishore369@gmail.com
> Subject: Re: [PATCH 2/2] fpga: Add support for Xilinx DFX AXI Shutdown
> manager
> 
> 
> On 1/14/21 5:34 PM, Nava kishore Manne wrote:
> > This patch adds support for Xilinx Dynamic Function eXchange(DFX) AXI
> > shutdown manager IP. It can be used to safely handling the AXI traffic
> > on a Reconfigurable Partition when it is undergoing dynamic
> > reconfiguration and there by preventing system deadlock that may occur
> > if AXI transactions are interrupted during reconfiguration.
> >
> > PR-Decoupler and AXI shutdown manager are completely different IPs.
> > But both the IP registers are compatible and also both belong to the
> > same sub-system (fpga-bridge).So using same driver for both IP's.
> >
> > Signed-off-by: Nava kishore Manne <nava.manne@xilinx.com>
> > ---
> >  drivers/fpga/xilinx-pr-decoupler.c | 35
> > ++++++++++++++++++++++++++----
> 
> It looks like the copyright is wrong, please review spelling of Xilix
> 
>  * Copyright (c) 2017, Xilix Inc
> 
Will fix in v2.
> 
> >  1 file changed, 31 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/fpga/xilinx-pr-decoupler.c
> > b/drivers/fpga/xilinx-pr-decoupler.c
> > index 7d69af230567..c95f3d065ccb 100644
> > --- a/drivers/fpga/xilinx-pr-decoupler.c
> > +++ b/drivers/fpga/xilinx-pr-decoupler.c
> > @@ -19,10 +19,15 @@
> >  #define CTRL_OFFSET		0
> >
> >  struct xlnx_pr_decoupler_data {
> > +	const struct xlnx_config_data *ipconfig;
> >  	void __iomem *io_base;
> >  	struct clk *clk;
> >  };
> >
> > +struct xlnx_config_data {
> > +	char *name;
> > +};
> 
> Move xlnx_config_data above xlnx_pr_decouple_data.
> 
Will fix in v2.

> could you 'const' char *name ?
> 
Will fix in v2.
> > +
> >  static inline void xlnx_pr_decoupler_write(struct xlnx_pr_decoupler_data
> *d,
> >  					   u32 offset, u32 val)
> >  {
> > @@ -76,15 +81,28 @@ static const struct fpga_bridge_ops
> xlnx_pr_decoupler_br_ops = {
> >  	.enable_show = xlnx_pr_decoupler_enable_show,  };
> >
> > +static const struct xlnx_config_data decoupler_config = {
> > +	.name = "Xilinx PR Decoupler",
> > +};
> > +
> > +static const struct xlnx_config_data shutdown_config = {
> > +	.name = "Xilinx DFX AXI shutdown mgr",
> 
> To be consistent with decoupler name,
> 
> shutdown mgr -> Shutdown Manager
> 

Will fix in v2.

> > +};
> > +
> >  static const struct of_device_id xlnx_pr_decoupler_of_match[] = {
> > -	{ .compatible = "xlnx,pr-decoupler-1.00", },
> > -	{ .compatible = "xlnx,pr-decoupler", },
> > +	{ .compatible = "xlnx,pr-decoupler-1.00", .data = &decoupler_config
> },
> > +	{ .compatible = "xlnx,pr-decoupler", .data = &decoupler_config },
> > +	{ .compatible = "xlnx,dfx-axi-shutdown-manager-1.00",
> > +					.data = &shutdown_config },
> > +	{ .compatible = "xlnx,dfx-axi-shutdown-manager",
> > +					.data = &shutdown_config },
> >  	{},
> >  };
> >  MODULE_DEVICE_TABLE(of, xlnx_pr_decoupler_of_match);
> >
> >  static int xlnx_pr_decoupler_probe(struct platform_device *pdev)  {
> > +	struct device_node *np = pdev->dev.of_node;
> >  	struct xlnx_pr_decoupler_data *priv;
> >  	struct fpga_bridge *br;
> >  	int err;
> > @@ -94,6 +112,14 @@ static int xlnx_pr_decoupler_probe(struct
> platform_device *pdev)
> >  	if (!priv)
> >  		return -ENOMEM;
> >
> > +	if (np) {
> > +		const struct of_device_id *match;
> > +
> > +		match = of_match_node(xlnx_pr_decoupler_of_match, np);
> > +		if (match && match->data)
> > +			priv->ipconfig = match->data;
> > +	}
> > +
> >  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> >  	priv->io_base = devm_ioremap_resource(&pdev->dev, res);
> >  	if (IS_ERR(priv->io_base))
> > @@ -114,7 +140,7 @@ static int xlnx_pr_decoupler_probe(struct
> > platform_device *pdev)
> >
> >  	clk_disable(priv->clk);
> >
> > -	br = devm_fpga_bridge_create(&pdev->dev, "Xilinx PR Decoupler",
> > +	br = devm_fpga_bridge_create(&pdev->dev, priv->ipconfig->name,
> >  				     &xlnx_pr_decoupler_br_ops, priv);
> >  	if (!br) {
> >  		err = -ENOMEM;
> > @@ -125,7 +151,8 @@ static int xlnx_pr_decoupler_probe(struct
> > platform_device *pdev)
> >
> >  	err = fpga_bridge_register(br);
> >  	if (err) {
> > -		dev_err(&pdev->dev, "unable to register Xilinx PR
> Decoupler");
> > +		dev_err(&pdev->dev, "unable to register %s",
> > +			priv->ipconfig->name);
> >  		goto err_clk;
> >  	}
> 
> Look at XILINX_PR_DECOUPLER entry in Kconfig, maybe add something like
> 
> help
> 
>   Say Y to enable drivers for the  ... Decoupler or DFX AIX Shutdown Manager
>

Will in v2.

Regards,
Navakishore.
Nava kishore Manne Jan. 19, 2021, 6:34 a.m. UTC | #4
Hi Moritz,

	Thanks for the review.
Please find my response inline.

> -----Original Message-----
> From: Moritz Fischer <mdf@kernel.org>
> Sent: Saturday, January 16, 2021 8:28 AM
> To: Nava kishore Manne <navam@xilinx.com>
> Cc: mdf@kernel.org; trix@redhat.com; robh+dt@kernel.org; Michal Simek
> <michals@xilinx.com>; linux-fpga@vger.kernel.org;
> devicetree@vger.kernel.org; linux-arm-kernel@lists.infradead.org; linux-
> kernel@vger.kernel.org; git <git@xilinx.com>; chinnikishore369@gmail.com
> Subject: Re: [PATCH 2/2] fpga: Add support for Xilinx DFX AXI Shutdown
> manager
> 
> Hi,
> 
> On Fri, Jan 15, 2021 at 07:04:31AM +0530, Nava kishore Manne wrote:
> > This patch adds support for Xilinx Dynamic Function eXchange(DFX) AXI
> > shutdown manager IP. It can be used to safely handling the AXI traffic
> > on a Reconfigurable Partition when it is undergoing dynamic
> > reconfiguration and there by preventing system deadlock that may occur
> > if AXI transactions are interrupted during reconfiguration.
> >
> > PR-Decoupler and AXI shutdown manager are completely different IPs.
> > But both the IP registers are compatible and also both belong to the
> > same sub-system (fpga-bridge).So using same driver for both IP's.
> 
> I'm a bit confused, the whole goal here is to give the thing a different name?


Both the PR Decoupler and AXI Shutdown IP manager IP's are follows same register spec.
Most of the code is common so we thought of reusing  same driver for AXI shutdown manager as well.

> >
> > Signed-off-by: Nava kishore Manne <nava.manne@xilinx.com>
> > ---
> >  drivers/fpga/xilinx-pr-decoupler.c | 35
> > ++++++++++++++++++++++++++----
> >  1 file changed, 31 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/fpga/xilinx-pr-decoupler.c
> > b/drivers/fpga/xilinx-pr-decoupler.c
> > index 7d69af230567..c95f3d065ccb 100644
> > --- a/drivers/fpga/xilinx-pr-decoupler.c
> > +++ b/drivers/fpga/xilinx-pr-decoupler.c
> > @@ -19,10 +19,15 @@
> >  #define CTRL_OFFSET		0
> >
> >  struct xlnx_pr_decoupler_data {
> > +	const struct xlnx_config_data *ipconfig;
> >  	void __iomem *io_base;
> >  	struct clk *clk;
> >  };
> >
> > +struct xlnx_config_data {
> > +	char *name;
> > +};
> > +
> >  static inline void xlnx_pr_decoupler_write(struct xlnx_pr_decoupler_data
> *d,
> >  					   u32 offset, u32 val)
> >  {
> > @@ -76,15 +81,28 @@ static const struct fpga_bridge_ops
> xlnx_pr_decoupler_br_ops = {
> >  	.enable_show = xlnx_pr_decoupler_enable_show,  };
> >
> > +static const struct xlnx_config_data decoupler_config = {
> > +	.name = "Xilinx PR Decoupler",
> > +};
> > +
> > +static const struct xlnx_config_data shutdown_config = {
> > +	.name = "Xilinx DFX AXI shutdown mgr", };
> 
> If it's just the strings, why not store them as is?

In order to differentiate the IP's at probe time we are using this name filed.

> > +
> >  static const struct of_device_id xlnx_pr_decoupler_of_match[] = {
> > -	{ .compatible = "xlnx,pr-decoupler-1.00", },
> > -	{ .compatible = "xlnx,pr-decoupler", },
> > +	{ .compatible = "xlnx,pr-decoupler-1.00", .data = &decoupler_config
> },
> > +	{ .compatible = "xlnx,pr-decoupler", .data = &decoupler_config },
> > +	{ .compatible = "xlnx,dfx-axi-shutdown-manager-1.00",
> > +					.data = &shutdown_config },
> > +	{ .compatible = "xlnx,dfx-axi-shutdown-manager",
> > +					.data = &shutdown_config },
> >  	{},
> >  };
> >  MODULE_DEVICE_TABLE(of, xlnx_pr_decoupler_of_match);
> >
> >  static int xlnx_pr_decoupler_probe(struct platform_device *pdev)  {
> > +	struct device_node *np = pdev->dev.of_node;
> >  	struct xlnx_pr_decoupler_data *priv;
> >  	struct fpga_bridge *br;
> >  	int err;
> > @@ -94,6 +112,14 @@ static int xlnx_pr_decoupler_probe(struct
> platform_device *pdev)
> >  	if (!priv)
> >  		return -ENOMEM;
> >
> > +	if (np) {
> > +		const struct of_device_id *match;
> > +
> > +		match = of_match_node(xlnx_pr_decoupler_of_match, np);
> > +		if (match && match->data)
> > +			priv->ipconfig = match->data;
> > +	}
> > +
> >  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> >  	priv->io_base = devm_ioremap_resource(&pdev->dev, res);
> >  	if (IS_ERR(priv->io_base))
> > @@ -114,7 +140,7 @@ static int xlnx_pr_decoupler_probe(struct
> > platform_device *pdev)
> >
> >  	clk_disable(priv->clk);
> >
> > -	br = devm_fpga_bridge_create(&pdev->dev, "Xilinx PR Decoupler",
> > +	br = devm_fpga_bridge_create(&pdev->dev, priv->ipconfig->name,
> >  				     &xlnx_pr_decoupler_br_ops, priv);
> >  	if (!br) {
> >  		err = -ENOMEM;
> > @@ -125,7 +151,8 @@ static int xlnx_pr_decoupler_probe(struct
> > platform_device *pdev)
> >
> >  	err = fpga_bridge_register(br);
> >  	if (err) {
> > -		dev_err(&pdev->dev, "unable to register Xilinx PR
> Decoupler");
> > +		dev_err(&pdev->dev, "unable to register %s",
> > +			priv->ipconfig->name);
> >  		goto err_clk;
> >  	}
> >
> > --
> > 2.18.0
> >
> 

Regards,
Navakishore.
Moritz Fischer Jan. 22, 2021, 5:15 a.m. UTC | #5
On Tue, Jan 19, 2021 at 06:34:54AM +0000, Nava kishore Manne wrote:
> Hi Moritz,
> 
> 	Thanks for the review.
> Please find my response inline.
> 
> > -----Original Message-----
> > From: Moritz Fischer <mdf@kernel.org>
> > Sent: Saturday, January 16, 2021 8:28 AM
> > To: Nava kishore Manne <navam@xilinx.com>
> > Cc: mdf@kernel.org; trix@redhat.com; robh+dt@kernel.org; Michal Simek
> > <michals@xilinx.com>; linux-fpga@vger.kernel.org;
> > devicetree@vger.kernel.org; linux-arm-kernel@lists.infradead.org; linux-
> > kernel@vger.kernel.org; git <git@xilinx.com>; chinnikishore369@gmail.com
> > Subject: Re: [PATCH 2/2] fpga: Add support for Xilinx DFX AXI Shutdown
> > manager
> > 
> > Hi,
> > 
> > On Fri, Jan 15, 2021 at 07:04:31AM +0530, Nava kishore Manne wrote:
> > > This patch adds support for Xilinx Dynamic Function eXchange(DFX) AXI
> > > shutdown manager IP. It can be used to safely handling the AXI traffic
> > > on a Reconfigurable Partition when it is undergoing dynamic
> > > reconfiguration and there by preventing system deadlock that may occur
> > > if AXI transactions are interrupted during reconfiguration.
> > >
> > > PR-Decoupler and AXI shutdown manager are completely different IPs.
> > > But both the IP registers are compatible and also both belong to the
> > > same sub-system (fpga-bridge).So using same driver for both IP's.
> > 
> > I'm a bit confused, the whole goal here is to give the thing a different name?
> 
> 
> Both the PR Decoupler and AXI Shutdown IP manager IP's are follows same register spec.
> Most of the code is common so we thought of reusing  same driver for AXI shutdown manager as well.

What are the differences, though other than it shows a different name?
> 
> > >
> > > Signed-off-by: Nava kishore Manne <nava.manne@xilinx.com>
> > > ---
> > >  drivers/fpga/xilinx-pr-decoupler.c | 35
> > > ++++++++++++++++++++++++++----
> > >  1 file changed, 31 insertions(+), 4 deletions(-)
> > >
> > > diff --git a/drivers/fpga/xilinx-pr-decoupler.c
> > > b/drivers/fpga/xilinx-pr-decoupler.c
> > > index 7d69af230567..c95f3d065ccb 100644
> > > --- a/drivers/fpga/xilinx-pr-decoupler.c
> > > +++ b/drivers/fpga/xilinx-pr-decoupler.c
> > > @@ -19,10 +19,15 @@
> > >  #define CTRL_OFFSET		0
> > >
> > >  struct xlnx_pr_decoupler_data {
> > > +	const struct xlnx_config_data *ipconfig;
> > >  	void __iomem *io_base;
> > >  	struct clk *clk;
> > >  };
> > >
> > > +struct xlnx_config_data {
> > > +	char *name;
> > > +};
> > > +
> > >  static inline void xlnx_pr_decoupler_write(struct xlnx_pr_decoupler_data
> > *d,
> > >  					   u32 offset, u32 val)
> > >  {
> > > @@ -76,15 +81,28 @@ static const struct fpga_bridge_ops
> > xlnx_pr_decoupler_br_ops = {
> > >  	.enable_show = xlnx_pr_decoupler_enable_show,  };
> > >
> > > +static const struct xlnx_config_data decoupler_config = {
> > > +	.name = "Xilinx PR Decoupler",
> > > +};
> > > +
> > > +static const struct xlnx_config_data shutdown_config = {
> > > +	.name = "Xilinx DFX AXI shutdown mgr", };
> > 
> > If it's just the strings, why not store them as is?
> 
> In order to differentiate the IP's at probe time we are using this name filed.
> 
> > > +
> > >  static const struct of_device_id xlnx_pr_decoupler_of_match[] = {
> > > -	{ .compatible = "xlnx,pr-decoupler-1.00", },
> > > -	{ .compatible = "xlnx,pr-decoupler", },
> > > +	{ .compatible = "xlnx,pr-decoupler-1.00", .data = &decoupler_config
> > },
> > > +	{ .compatible = "xlnx,pr-decoupler", .data = &decoupler_config },
> > > +	{ .compatible = "xlnx,dfx-axi-shutdown-manager-1.00",
> > > +					.data = &shutdown_config },
> > > +	{ .compatible = "xlnx,dfx-axi-shutdown-manager",
> > > +					.data = &shutdown_config },
> > >  	{},
> > >  };
> > >  MODULE_DEVICE_TABLE(of, xlnx_pr_decoupler_of_match);
> > >
> > >  static int xlnx_pr_decoupler_probe(struct platform_device *pdev)  {
> > > +	struct device_node *np = pdev->dev.of_node;
> > >  	struct xlnx_pr_decoupler_data *priv;
> > >  	struct fpga_bridge *br;
> > >  	int err;
> > > @@ -94,6 +112,14 @@ static int xlnx_pr_decoupler_probe(struct
> > platform_device *pdev)
> > >  	if (!priv)
> > >  		return -ENOMEM;
> > >
> > > +	if (np) {
> > > +		const struct of_device_id *match;
> > > +
> > > +		match = of_match_node(xlnx_pr_decoupler_of_match, np);
> > > +		if (match && match->data)
> > > +			priv->ipconfig = match->data;
> > > +	}
> > > +
> > >  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > >  	priv->io_base = devm_ioremap_resource(&pdev->dev, res);
> > >  	if (IS_ERR(priv->io_base))
> > > @@ -114,7 +140,7 @@ static int xlnx_pr_decoupler_probe(struct
> > > platform_device *pdev)
> > >
> > >  	clk_disable(priv->clk);
> > >
> > > -	br = devm_fpga_bridge_create(&pdev->dev, "Xilinx PR Decoupler",
> > > +	br = devm_fpga_bridge_create(&pdev->dev, priv->ipconfig->name,
> > >  				     &xlnx_pr_decoupler_br_ops, priv);
> > >  	if (!br) {
> > >  		err = -ENOMEM;
> > > @@ -125,7 +151,8 @@ static int xlnx_pr_decoupler_probe(struct
> > > platform_device *pdev)
> > >
> > >  	err = fpga_bridge_register(br);
> > >  	if (err) {
> > > -		dev_err(&pdev->dev, "unable to register Xilinx PR
> > Decoupler");
> > > +		dev_err(&pdev->dev, "unable to register %s",
> > > +			priv->ipconfig->name);
> > >  		goto err_clk;
> > >  	}
> > >
> > > --
> > > 2.18.0
> > >
> > 
> 
> Regards,
> Navakishore.
- Moritz
Nava kishore Manne Jan. 27, 2021, 8:46 a.m. UTC | #6
Hi Moritz,

	Please find my response inline.

> -----Original Message-----
> From: Moritz Fischer <mdf@kernel.org>
> Sent: Friday, January 22, 2021 10:45 AM
> To: Nava kishore Manne <navam@xilinx.com>
> Cc: Moritz Fischer <mdf@kernel.org>; trix@redhat.com;
> robh+dt@kernel.org; Michal Simek <michals@xilinx.com>; linux-
> fpga@vger.kernel.org; devicetree@vger.kernel.org; linux-arm-
> kernel@lists.infradead.org; linux-kernel@vger.kernel.org; git
> <git@xilinx.com>; chinnikishore369@gmail.com
> Subject: Re: [PATCH 2/2] fpga: Add support for Xilinx DFX AXI Shutdown
> manager
> 
> On Tue, Jan 19, 2021 at 06:34:54AM +0000, Nava kishore Manne wrote:
> > Hi Moritz,
> >
> > 	Thanks for the review.
> > Please find my response inline.
> >
> > > -----Original Message-----
> > > From: Moritz Fischer <mdf@kernel.org>
> > > Sent: Saturday, January 16, 2021 8:28 AM
> > > To: Nava kishore Manne <navam@xilinx.com>
> > > Cc: mdf@kernel.org; trix@redhat.com; robh+dt@kernel.org; Michal
> > > Simek <michals@xilinx.com>; linux-fpga@vger.kernel.org;
> > > devicetree@vger.kernel.org; linux-arm-kernel@lists.infradead.org;
> > > linux- kernel@vger.kernel.org; git <git@xilinx.com>;
> > > chinnikishore369@gmail.com
> > > Subject: Re: [PATCH 2/2] fpga: Add support for Xilinx DFX AXI
> > > Shutdown manager
> > >
> > > Hi,
> > >
> > > On Fri, Jan 15, 2021 at 07:04:31AM +0530, Nava kishore Manne wrote:
> > > > This patch adds support for Xilinx Dynamic Function eXchange(DFX)
> > > > AXI shutdown manager IP. It can be used to safely handling the AXI
> > > > traffic on a Reconfigurable Partition when it is undergoing
> > > > dynamic reconfiguration and there by preventing system deadlock
> > > > that may occur if AXI transactions are interrupted during
> reconfiguration.
> > > >
> > > > PR-Decoupler and AXI shutdown manager are completely different IPs.
> > > > But both the IP registers are compatible and also both belong to
> > > > the same sub-system (fpga-bridge).So using same driver for both IP's.
> > >
> > > I'm a bit confused, the whole goal here is to give the thing a different
> name?
> >
> >
> > Both the PR Decoupler and AXI Shutdown IP manager IP's are follows same
> register spec.
> > Most of the code is common so we thought of reusing  same driver for AXI
> shutdown manager as well.
> 
> What are the differences, though other than it shows a different name?

The PR-Decoupler And Axi Shut down manager are different IP's 

PR-Decoupler IP can be used to make the interface between a Reconfigurable Partition
and the static logic safe while Partial Reconfiguration is occurring. When active,
user-selected signals crossing between the Reconfigurable Partition and the static logic
are driven to user configurable values. When inactive, signals are passed unaltered.

Coming to the Axi Shutdown manager IP it's safely handles AXI4MM and AXI4-Lite interfaces
on a Reconfigurable Partition when it is undergoing dynamic reconfiguration (DFX),
preventing system deadlock that can occur if AXI transactions are interrupted by DFX.

For more details please refer the below links:
https://www.xilinx.com/support/documentation/ip_documentation/pr_decoupler/v1_0/pg227-pr-decoupler.pdf 
https://www.xilinx.com/support/documentation/ip_documentation/dfx_axi_shutdown_manager/v1_0/pg377-dfx-axi-shutdown-manager.pdf  

Both the IP functionality's are different but the IP's registers spec is same and also they fall under
the same bridge drivers category and most of the code is common except the naming conventions.
So we thought of using the same driver for both the IP's with different naming conventions.

Regards,
Navakishore.
diff mbox series

Patch

diff --git a/drivers/fpga/xilinx-pr-decoupler.c b/drivers/fpga/xilinx-pr-decoupler.c
index 7d69af230567..c95f3d065ccb 100644
--- a/drivers/fpga/xilinx-pr-decoupler.c
+++ b/drivers/fpga/xilinx-pr-decoupler.c
@@ -19,10 +19,15 @@ 
 #define CTRL_OFFSET		0
 
 struct xlnx_pr_decoupler_data {
+	const struct xlnx_config_data *ipconfig;
 	void __iomem *io_base;
 	struct clk *clk;
 };
 
+struct xlnx_config_data {
+	char *name;
+};
+
 static inline void xlnx_pr_decoupler_write(struct xlnx_pr_decoupler_data *d,
 					   u32 offset, u32 val)
 {
@@ -76,15 +81,28 @@  static const struct fpga_bridge_ops xlnx_pr_decoupler_br_ops = {
 	.enable_show = xlnx_pr_decoupler_enable_show,
 };
 
+static const struct xlnx_config_data decoupler_config = {
+	.name = "Xilinx PR Decoupler",
+};
+
+static const struct xlnx_config_data shutdown_config = {
+	.name = "Xilinx DFX AXI shutdown mgr",
+};
+
 static const struct of_device_id xlnx_pr_decoupler_of_match[] = {
-	{ .compatible = "xlnx,pr-decoupler-1.00", },
-	{ .compatible = "xlnx,pr-decoupler", },
+	{ .compatible = "xlnx,pr-decoupler-1.00", .data = &decoupler_config },
+	{ .compatible = "xlnx,pr-decoupler", .data = &decoupler_config },
+	{ .compatible = "xlnx,dfx-axi-shutdown-manager-1.00",
+					.data = &shutdown_config },
+	{ .compatible = "xlnx,dfx-axi-shutdown-manager",
+					.data = &shutdown_config },
 	{},
 };
 MODULE_DEVICE_TABLE(of, xlnx_pr_decoupler_of_match);
 
 static int xlnx_pr_decoupler_probe(struct platform_device *pdev)
 {
+	struct device_node *np = pdev->dev.of_node;
 	struct xlnx_pr_decoupler_data *priv;
 	struct fpga_bridge *br;
 	int err;
@@ -94,6 +112,14 @@  static int xlnx_pr_decoupler_probe(struct platform_device *pdev)
 	if (!priv)
 		return -ENOMEM;
 
+	if (np) {
+		const struct of_device_id *match;
+
+		match = of_match_node(xlnx_pr_decoupler_of_match, np);
+		if (match && match->data)
+			priv->ipconfig = match->data;
+	}
+
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	priv->io_base = devm_ioremap_resource(&pdev->dev, res);
 	if (IS_ERR(priv->io_base))
@@ -114,7 +140,7 @@  static int xlnx_pr_decoupler_probe(struct platform_device *pdev)
 
 	clk_disable(priv->clk);
 
-	br = devm_fpga_bridge_create(&pdev->dev, "Xilinx PR Decoupler",
+	br = devm_fpga_bridge_create(&pdev->dev, priv->ipconfig->name,
 				     &xlnx_pr_decoupler_br_ops, priv);
 	if (!br) {
 		err = -ENOMEM;
@@ -125,7 +151,8 @@  static int xlnx_pr_decoupler_probe(struct platform_device *pdev)
 
 	err = fpga_bridge_register(br);
 	if (err) {
-		dev_err(&pdev->dev, "unable to register Xilinx PR Decoupler");
+		dev_err(&pdev->dev, "unable to register %s",
+			priv->ipconfig->name);
 		goto err_clk;
 	}