Implement a platform driver that matches with xlnx,
sd-fec-1.1 device tree node and registers as a character
device, including:
- SD-FEC driver binds to sdfec DT node.
- creates and initialise an initial driver dev structure.
- add the driver in Linux build and Kconfig.

Tested-by: Dragan Cvetic <dragan.cve...@xilinx.com>
Signed-off-by: Derek Kiernan <derek.kier...@xilinx.com>
Signed-off-by: Dragan Cvetic <dragan.cve...@xilinx.com>
---
 drivers/misc/Kconfig        |  12 ++++
 drivers/misc/Makefile       |   1 +
 drivers/misc/xilinx_sdfec.c | 162 ++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 175 insertions(+)
 create mode 100644 drivers/misc/xilinx_sdfec.c

diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 6b0417b..319a6bf 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -471,6 +471,18 @@ config PCI_ENDPOINT_TEST
            Enable this configuration option to enable the host side test driver
            for PCI Endpoint.
 
+config XILINX_SDFEC
+       tristate "Xilinx SDFEC 16"
+       help
+         This option enables support for the Xilinx SDFEC (Soft Decision
+         Forward Error Correction) driver. This enables a char driver
+         for the SDFEC.
+
+         You may select this driver if your design instantiates the
+         SDFEC(16nm) hardened block. To compile this as a module choose M.
+
+         If unsure, say N.
+
 config MISC_RTSX
        tristate
        default MISC_RTSX_PCI || MISC_RTSX_USB
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index b9affcd..0cb3546 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -59,3 +59,4 @@ obj-$(CONFIG_OCXL)            += ocxl/
 obj-y                          += cardreader/
 obj-$(CONFIG_PVPANIC)          += pvpanic.o
 obj-$(CONFIG_HABANA_AI)                += habanalabs/
+obj-$(CONFIG_XILINX_SDFEC)     += xilinx_sdfec.o
diff --git a/drivers/misc/xilinx_sdfec.c b/drivers/misc/xilinx_sdfec.c
new file mode 100644
index 0000000..ff0704b
--- /dev/null
+++ b/drivers/misc/xilinx_sdfec.c
@@ -0,0 +1,162 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Xilinx SDFEC
+ *
+ * Copyright (C) 2019 Xilinx, Inc.
+ *
+ * Description:
+ * This driver is developed for SDFEC16 (Soft Decision FEC 16nm)
+ * IP. It exposes a char device which supports file operations
+ * like  open(), close() and ioctl().
+ */
+
+#include <linux/miscdevice.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/poll.h>
+#include <linux/slab.h>
+#include <linux/clk.h>
+
+#define DEV_NAME_LEN 12
+
+static struct idr dev_idr;
+static struct mutex dev_idr_lock;
+
+/**
+ * struct xsdfec_dev - Driver data for SDFEC
+ * @regs: device physical base address
+ * @dev: pointer to device struct
+ * @miscdev: Misc device handle
+ * @error_data_lock: Error counter and states spinlock
+ * @dev_name: Device name
+ * @dev_id: Device ID
+ *
+ * This structure contains necessary state for SDFEC driver to operate
+ */
+struct xsdfec_dev {
+       void __iomem *regs;
+       struct device *dev;
+       struct miscdevice miscdev;
+       /* Spinlock to protect state_updated and stats_updated */
+       spinlock_t error_data_lock;
+       char dev_name[DEV_NAME_LEN];
+       int dev_id;
+};
+
+static const struct file_operations xsdfec_fops = {
+       .owner = THIS_MODULE,
+};
+
+static void xsdfec_idr_remove(struct xsdfec_dev *xsdfec)
+{
+       mutex_lock(&dev_idr_lock);
+       idr_remove(&dev_idr, xsdfec->dev_id);
+       mutex_unlock(&dev_idr_lock);
+}
+
+static int xsdfec_probe(struct platform_device *pdev)
+{
+       struct xsdfec_dev *xsdfec;
+       struct device *dev;
+       struct resource *res;
+       int err;
+
+       xsdfec = devm_kzalloc(&pdev->dev, sizeof(*xsdfec), GFP_KERNEL);
+       if (!xsdfec)
+               return -ENOMEM;
+
+       xsdfec->dev = &pdev->dev;
+       spin_lock_init(&xsdfec->error_data_lock);
+
+       dev = xsdfec->dev;
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       xsdfec->regs = devm_ioremap_resource(dev, res);
+       if (IS_ERR(xsdfec->regs)) {
+               err = PTR_ERR(xsdfec->regs);
+               return err;
+       }
+
+       /* Save driver private data */
+       platform_set_drvdata(pdev, xsdfec);
+
+       mutex_lock(&dev_idr_lock);
+       err = idr_alloc(&dev_idr, xsdfec->dev_name, 0, 0, GFP_KERNEL);
+       mutex_unlock(&dev_idr_lock);
+       if (err < 0)
+               goto err_xsddev_idr;
+       xsdfec->dev_id = err;
+
+       snprintf(xsdfec->dev_name, DEV_NAME_LEN, "xsdfec%d", xsdfec->dev_id);
+       xsdfec->miscdev.minor = MISC_DYNAMIC_MINOR;
+       xsdfec->miscdev.name = xsdfec->dev_name;
+       xsdfec->miscdev.fops = &xsdfec_fops;
+       xsdfec->miscdev.parent = dev;
+       err = misc_register(&xsdfec->miscdev);
+       if (err) {
+               dev_err(dev, "error:%d. Unable to register device", err);
+               return err;
+       }
+       return 0;
+
+err_xsddev_idr:
+       xsdfec_idr_remove(xsdfec);
+
+       return err;
+}
+
+static int xsdfec_remove(struct platform_device *pdev)
+{
+       struct xsdfec_dev *xsdfec;
+
+       xsdfec = platform_get_drvdata(pdev);
+       misc_deregister(&xsdfec->miscdev);
+       xsdfec_idr_remove(xsdfec);
+       return 0;
+}
+
+static const struct of_device_id xsdfec_of_match[] = {
+       {
+               .compatible = "xlnx,sd-fec-1.1",
+       },
+       { /* end of table */ }
+};
+MODULE_DEVICE_TABLE(of, xsdfec_of_match);
+
+static struct platform_driver xsdfec_driver = {
+       .driver = {
+               .name = "xilinx-sdfec",
+               .of_match_table = xsdfec_of_match,
+       },
+       .probe = xsdfec_probe,
+       .remove =  xsdfec_remove,
+};
+
+static int __init xsdfec_init(void)
+{
+       int err;
+
+       mutex_init(&dev_idr_lock);
+       idr_init(&dev_idr);
+       err = platform_driver_register(&xsdfec_driver);
+       if (err < 0) {
+               pr_err("%s Unabled to register SDFEC driver", __func__);
+               return err;
+       }
+       return 0;
+}
+
+static void __exit xsdfec_exit(void)
+{
+       platform_driver_unregister(&xsdfec_driver);
+       idr_destroy(&dev_idr);
+}
+
+module_init(xsdfec_init);
+module_exit(xsdfec_exit);
+
+MODULE_AUTHOR("Xilinx, Inc");
+MODULE_DESCRIPTION("Xilinx SD-FEC16 Driver");
+MODULE_LICENSE("GPL");
-- 
2.7.4

Reply via email to