[v2,2/2] fpga: Add support for Xilinx LogiCORE PR Decoupler

Submitted by mdf@kernel.org on March 17, 2017, 12:51 a.m.

Details

Message ID 1489711910-17443-2-git-send-email-mdf@kernel.org
State New
Headers show

Commit Message

mdf@kernel.org March 17, 2017, 12:51 a.m.
This adds support for the Xilinx LogiCORE PR Decoupler
soft-ip that does decoupling of PR regions in the FPGA
fabric during partial reconfiguration.

Signed-off-by: Moritz Fischer <mdf@kernel.org>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Sören Brinkmann <soren.brinkmann@xilinx.com>
Cc: linux-kernel@vger.kernel.org
Cc: devicetree@vger.kernel.org
---

Changes from v1:
- Added Michal as Co-Author since I pulled in some of his code
- Reworked clk handling in _remove()
- Pulled in Michal's version of show_enable(), ditched priv->enabled

---
 drivers/fpga/Kconfig               |   9 +++
 drivers/fpga/Makefile              |   1 +
 drivers/fpga/xilinx-pr-decoupler.c | 147 +++++++++++++++++++++++++++++++++++++
 3 files changed, 157 insertions(+)
 create mode 100644 drivers/fpga/xilinx-pr-decoupler.c

Comments

Michal Simek March 17, 2017, 10:54 a.m.
On 17.3.2017 01:51, Moritz Fischer wrote:
> This adds support for the Xilinx LogiCORE PR Decoupler
> soft-ip that does decoupling of PR regions in the FPGA
> fabric during partial reconfiguration.
> 
> Signed-off-by: Moritz Fischer <mdf@kernel.org>
> Cc: Michal Simek <michal.simek@xilinx.com>
> Cc: Sören Brinkmann <soren.brinkmann@xilinx.com>
> Cc: linux-kernel@vger.kernel.org
> Cc: devicetree@vger.kernel.org
> ---
> 
> Changes from v1:
> - Added Michal as Co-Author since I pulled in some of his code
> - Reworked clk handling in _remove()
> - Pulled in Michal's version of show_enable(), ditched priv->enabled
> 
> ---
>  drivers/fpga/Kconfig               |   9 +++
>  drivers/fpga/Makefile              |   1 +
>  drivers/fpga/xilinx-pr-decoupler.c | 147 +++++++++++++++++++++++++++++++++++++
>  3 files changed, 157 insertions(+)
>  create mode 100644 drivers/fpga/xilinx-pr-decoupler.c
> 
> diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
> index 967cda4..e42c7dc 100644
> --- a/drivers/fpga/Kconfig
> +++ b/drivers/fpga/Kconfig
> @@ -69,6 +69,15 @@ config ALTERA_FREEZE_BRIDGE
>  	  isolate one region of the FPGA from the busses while that
>  	  region is being reprogrammed.
>  
> +config XILINX_PR_DECOUPLER
> +	tristate "Xilinx LogiCORE PR Decoupler"
> +	depends on FPGA_BRIDGE
> +	help
> +	  Say Y to enable drivers for Xilinx LogiCORE PR Decoupler.
> +	  The PR Decoupler exists in the FPGA fabric to isolate one
> +	  region of the FPGA from the busses while that region is
> +	  being reprogrammed during partial reconfig.
> +
>  endif # FPGA
>  
>  endmenu
> diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
> index cc0d364..3f04bcf 100644
> --- a/drivers/fpga/Makefile
> +++ b/drivers/fpga/Makefile
> @@ -15,6 +15,7 @@ obj-$(CONFIG_FPGA_MGR_ZYNQ_FPGA)	+= zynq-fpga.o
>  obj-$(CONFIG_FPGA_BRIDGE)		+= fpga-bridge.o
>  obj-$(CONFIG_SOCFPGA_FPGA_BRIDGE)	+= altera-hps2fpga.o altera-fpga2sdram.o
>  obj-$(CONFIG_ALTERA_FREEZE_BRIDGE)	+= altera-freeze-bridge.o
> +obj-$(CONFIG_XILINX_PR_DECOUPLER)	+= xilinx-pr-decoupler.o
>  
>  # High Level Interfaces
>  obj-$(CONFIG_FPGA_REGION)		+= fpga-region.o
> diff --git a/drivers/fpga/xilinx-pr-decoupler.c b/drivers/fpga/xilinx-pr-decoupler.c
> new file mode 100644
> index 0000000..761700c
> --- /dev/null
> +++ b/drivers/fpga/xilinx-pr-decoupler.c
> @@ -0,0 +1,147 @@
> +/*
> + * Copyright (c) 2017, National Instruments Corp.
> + * Copyright (c) 2017, Xilix Inc
> + *
> + * FPGA Bridge Driver for the Xilinx LogiCORE Partial Reconfiguration
> + * Decoupler IP Core.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; version 2 of the License.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/io.h>
> +#include <linux/kernel.h>
> +#include <linux/of_device.h>
> +#include <linux/module.h>
> +#include <linux/fpga/fpga-bridge.h>
> +
> +#define CTRL_CMD_DECOUPLE	BIT(0)
> +#define CTRL_CMD_COUPLE		~BIT(0)
> +
> +struct xlnx_pr_decoupler_data {
> +	void __iomem *io_base;
> +	struct clk *clk;
> +};
> +
> +static int xlnx_pr_decoupler_enable_set(struct fpga_bridge *bridge, bool enable)
> +{
> +	int err;
> +	struct xlnx_pr_decoupler_data *priv = bridge->priv;
> +
> +	err = clk_enable(priv->clk);
> +	if (err)
> +		return err;
> +
> +	if (enable)
> +		writel(CTRL_CMD_COUPLE, priv->io_base);
> +	else
> +		writel(CTRL_CMD_DECOUPLE, priv->io_base);
> +
> +	clk_disable(priv->clk);
> +
> +	return 0;
> +}
> +
> +static int xlnx_pr_decoupler_enable_show(struct fpga_bridge *bridge)
> +{
> +	const struct xlnx_pr_decoupler_data *priv = bridge->priv;
> +	u32 status;
> +	int err;
> +
> +	err = clk_enable(priv->clk);
> +	if (err)
> +		return err;
> +
> +	status = readl(priv->io_base);
> +
> +	clk_disable(priv->clk);
> +
> +	return !status;
> +}
> +
> +static struct fpga_bridge_ops xlnx_pr_decoupler_br_ops = {
> +	.enable_set = xlnx_pr_decoupler_enable_set,
> +	.enable_show = xlnx_pr_decoupler_enable_show,
> +};
> +
> +static const struct of_device_id xlnx_pr_decoupler_of_match[] = {
> +	{ .compatible = "xlnx,pr-decoupler-1.00", },

I would add here that generic compatible string too.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>

Thanks,
Michal
kbuild test robot March 19, 2017, 5:30 p.m.
Hi Moritz,

[auto build test WARNING on linus/master]
[also build test WARNING on v4.11-rc2 next-20170310]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Moritz-Fischer/doc-Add-bindings-document-for-Xilinx-LogiCore-PR-Decoupler/20170320-005406
config: ia64-allmodconfig (attached as .config)
compiler: ia64-linux-gcc (GCC) 6.2.0
reproduce:
        wget https://raw.githubusercontent.com/01org/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=ia64 

All warnings (new ones prefixed by >>):

   In file included from include/linux/io.h:25:0,
                    from drivers/fpga/xilinx-pr-decoupler.c:19:
   drivers/fpga/xilinx-pr-decoupler.c: In function 'xlnx_pr_decoupler_enable_set':
   arch/ia64/include/asm/io.h:395:30: warning: large integer implicitly truncated to unsigned type [-Woverflow]
    #define writel(v,a) __writel((v), (a))
                                 ^
>> drivers/fpga/xilinx-pr-decoupler.c:43:3: note: in expansion of macro 'writel'
      writel(CTRL_CMD_COUPLE, priv->io_base);
      ^~~~~~

vim +/writel +43 drivers/fpga/xilinx-pr-decoupler.c

    13	 * but WITHOUT ANY WARRANTY; without even the implied warranty of
    14	 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    15	 * GNU General Public License for more details.
    16	 */
    17	
    18	#include <linux/clk.h>
  > 19	#include <linux/io.h>
    20	#include <linux/kernel.h>
    21	#include <linux/of_device.h>
    22	#include <linux/module.h>
    23	#include <linux/fpga/fpga-bridge.h>
    24	
    25	#define CTRL_CMD_DECOUPLE	BIT(0)
    26	#define CTRL_CMD_COUPLE		~BIT(0)
    27	
    28	struct xlnx_pr_decoupler_data {
    29		void __iomem *io_base;
    30		struct clk *clk;
    31	};
    32	
    33	static int xlnx_pr_decoupler_enable_set(struct fpga_bridge *bridge, bool enable)
    34	{
    35		int err;
    36		struct xlnx_pr_decoupler_data *priv = bridge->priv;
    37	
    38		err = clk_enable(priv->clk);
    39		if (err)
    40			return err;
    41	
    42		if (enable)
  > 43			writel(CTRL_CMD_COUPLE, priv->io_base);
    44		else
    45			writel(CTRL_CMD_DECOUPLE, priv->io_base);
    46	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
kbuild test robot March 19, 2017, 5:48 p.m.
Hi Moritz,

[auto build test WARNING on linus/master]
[also build test WARNING on v4.11-rc2 next-20170310]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Moritz-Fischer/doc-Add-bindings-document-for-Xilinx-LogiCore-PR-Decoupler/20170320-005406
config: alpha-allyesconfig (attached as .config)
compiler: alpha-linux-gnu-gcc (Debian 6.1.1-9) 6.1.1 20160705
reproduce:
        wget https://raw.githubusercontent.com/01org/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=alpha 

All warnings (new ones prefixed by >>):

   drivers/fpga/xilinx-pr-decoupler.c: In function 'xlnx_pr_decoupler_enable_set':
>> drivers/fpga/xilinx-pr-decoupler.c:26:26: warning: large integer implicitly truncated to unsigned type [-Woverflow]
    #define CTRL_CMD_COUPLE  ~BIT(0)
                             ^
>> drivers/fpga/xilinx-pr-decoupler.c:43:10: note: in expansion of macro 'CTRL_CMD_COUPLE'
      writel(CTRL_CMD_COUPLE, priv->io_base);
             ^~~~~~~~~~~~~~~

vim +26 drivers/fpga/xilinx-pr-decoupler.c

    20	#include <linux/kernel.h>
    21	#include <linux/of_device.h>
    22	#include <linux/module.h>
    23	#include <linux/fpga/fpga-bridge.h>
    24	
    25	#define CTRL_CMD_DECOUPLE	BIT(0)
  > 26	#define CTRL_CMD_COUPLE		~BIT(0)
    27	
    28	struct xlnx_pr_decoupler_data {
    29		void __iomem *io_base;
    30		struct clk *clk;
    31	};
    32	
    33	static int xlnx_pr_decoupler_enable_set(struct fpga_bridge *bridge, bool enable)
    34	{
    35		int err;
    36		struct xlnx_pr_decoupler_data *priv = bridge->priv;
    37	
    38		err = clk_enable(priv->clk);
    39		if (err)
    40			return err;
    41	
    42		if (enable)
  > 43			writel(CTRL_CMD_COUPLE, priv->io_base);
    44		else
    45			writel(CTRL_CMD_DECOUPLE, priv->io_base);
    46	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

Patch hide | download patch | download mbox

diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
index 967cda4..e42c7dc 100644
--- a/drivers/fpga/Kconfig
+++ b/drivers/fpga/Kconfig
@@ -69,6 +69,15 @@  config ALTERA_FREEZE_BRIDGE
 	  isolate one region of the FPGA from the busses while that
 	  region is being reprogrammed.
 
+config XILINX_PR_DECOUPLER
+	tristate "Xilinx LogiCORE PR Decoupler"
+	depends on FPGA_BRIDGE
+	help
+	  Say Y to enable drivers for Xilinx LogiCORE PR Decoupler.
+	  The PR Decoupler exists in the FPGA fabric to isolate one
+	  region of the FPGA from the busses while that region is
+	  being reprogrammed during partial reconfig.
+
 endif # FPGA
 
 endmenu
diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
index cc0d364..3f04bcf 100644
--- a/drivers/fpga/Makefile
+++ b/drivers/fpga/Makefile
@@ -15,6 +15,7 @@  obj-$(CONFIG_FPGA_MGR_ZYNQ_FPGA)	+= zynq-fpga.o
 obj-$(CONFIG_FPGA_BRIDGE)		+= fpga-bridge.o
 obj-$(CONFIG_SOCFPGA_FPGA_BRIDGE)	+= altera-hps2fpga.o altera-fpga2sdram.o
 obj-$(CONFIG_ALTERA_FREEZE_BRIDGE)	+= altera-freeze-bridge.o
+obj-$(CONFIG_XILINX_PR_DECOUPLER)	+= xilinx-pr-decoupler.o
 
 # High Level Interfaces
 obj-$(CONFIG_FPGA_REGION)		+= fpga-region.o
diff --git a/drivers/fpga/xilinx-pr-decoupler.c b/drivers/fpga/xilinx-pr-decoupler.c
new file mode 100644
index 0000000..761700c
--- /dev/null
+++ b/drivers/fpga/xilinx-pr-decoupler.c
@@ -0,0 +1,147 @@ 
+/*
+ * Copyright (c) 2017, National Instruments Corp.
+ * Copyright (c) 2017, Xilix Inc
+ *
+ * FPGA Bridge Driver for the Xilinx LogiCORE Partial Reconfiguration
+ * Decoupler IP Core.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/of_device.h>
+#include <linux/module.h>
+#include <linux/fpga/fpga-bridge.h>
+
+#define CTRL_CMD_DECOUPLE	BIT(0)
+#define CTRL_CMD_COUPLE		~BIT(0)
+
+struct xlnx_pr_decoupler_data {
+	void __iomem *io_base;
+	struct clk *clk;
+};
+
+static int xlnx_pr_decoupler_enable_set(struct fpga_bridge *bridge, bool enable)
+{
+	int err;
+	struct xlnx_pr_decoupler_data *priv = bridge->priv;
+
+	err = clk_enable(priv->clk);
+	if (err)
+		return err;
+
+	if (enable)
+		writel(CTRL_CMD_COUPLE, priv->io_base);
+	else
+		writel(CTRL_CMD_DECOUPLE, priv->io_base);
+
+	clk_disable(priv->clk);
+
+	return 0;
+}
+
+static int xlnx_pr_decoupler_enable_show(struct fpga_bridge *bridge)
+{
+	const struct xlnx_pr_decoupler_data *priv = bridge->priv;
+	u32 status;
+	int err;
+
+	err = clk_enable(priv->clk);
+	if (err)
+		return err;
+
+	status = readl(priv->io_base);
+
+	clk_disable(priv->clk);
+
+	return !status;
+}
+
+static struct fpga_bridge_ops xlnx_pr_decoupler_br_ops = {
+	.enable_set = xlnx_pr_decoupler_enable_set,
+	.enable_show = xlnx_pr_decoupler_enable_show,
+};
+
+static const struct of_device_id xlnx_pr_decoupler_of_match[] = {
+	{ .compatible = "xlnx,pr-decoupler-1.00", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, xlnx_pr_decoupler_of_match);
+
+static int xlnx_pr_decoupler_probe(struct platform_device *pdev)
+{
+	struct xlnx_pr_decoupler_data *priv;
+	int err;
+	struct resource *res;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	priv->io_base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(priv->io_base))
+		return PTR_ERR(priv->io_base);
+
+	priv->clk = devm_clk_get(&pdev->dev, "aclk");
+	if (IS_ERR(priv->clk)) {
+		dev_err(&pdev->dev, "input clock not found\n");
+		return PTR_ERR(priv->clk);
+	}
+
+	err = clk_prepare_enable(priv->clk);
+	if (err) {
+		dev_err(&pdev->dev, "unable to enable clock\n");
+		return err;
+	}
+
+	clk_disable(priv->clk);
+
+	err = fpga_bridge_register(&pdev->dev, "Xilinx PR Decoupler",
+				   &xlnx_pr_decoupler_br_ops, priv);
+
+	if (err) {
+		dev_err(&pdev->dev, "unable to register Xilinx PR Decoupler");
+		clk_unprepare(priv->clk);
+		return err;
+	}
+
+	return 0;
+}
+
+static int xlnx_pr_decoupler_remove(struct platform_device *pdev)
+{
+	struct fpga_bridge *bridge = platform_get_drvdata(pdev);
+	struct xlnx_pr_decoupler_data *p = bridge->priv;
+
+	fpga_bridge_unregister(&pdev->dev);
+
+	clk_unprepare(p->clk);
+
+	return 0;
+}
+
+static struct platform_driver xlnx_pr_decoupler_driver = {
+	.probe = xlnx_pr_decoupler_probe,
+	.remove = xlnx_pr_decoupler_remove,
+	.driver = {
+		.name = "xlnx_pr_decoupler",
+		.of_match_table = of_match_ptr(xlnx_pr_decoupler_of_match),
+	},
+};
+
+module_platform_driver(xlnx_pr_decoupler_driver);
+
+MODULE_DESCRIPTION("Xilinx Partial Reconfiguration Decoupler");
+MODULE_AUTHOR("Moritz Fischer <mdf@kernel.org>");
+MODULE_AUTHOR("Michal Simek <michal.simek@xilinx.com>");
+MODULE_LICENSE("GPL v2");