fpga: fpga-mgr: Add debugfs entry for loading fpga image from user space

This patch adds an debugfs entry to load fpga image from user
provided address pointer and size.

--> Usage:
   debugfs_fd = open("/sys/kernel/debug/fpga/fpga0/load", O_WRONLY);
   write(debugfs_fd, Image_pointer, Image_size);

(OR)

   dd bs=26M if=/mnt/top.bin of=/sys/kernel/debug/fpga/fpga0/load

Signed-off-by: Appana Durga Kedareswara rao <appana.durga.rao@xilinx.com>
Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
index aa72476bc0696785c45f9bbab75e872ed8b78d3d..b4cc960f5331fcfbef3a589b757fe45a943062fc 100644 (file)
--- a/drivers/fpga/fpga-mgr.c
+++ b/drivers/fpga/fpga-mgr.c
@@ -657,6 +657,74 @@ static const struct file_operations fpga_mgr_ops_image = {
        .open = fpga_mgr_read_open,
        .read = seq_read,
 };
+
+/**
+ * fpga_mgr_debugfs_buf_load() - debugfs write function
+ * @file:      User file
+ * @ptr:       Fpga Image Address pointer
+ * @len:       Length of the image
+ * @off:       Offset within the file
+ *
+ * Return: Number of bytes if request succeeds,
+ *        the corresponding error code otherwise
+ */
+static ssize_t fpga_mgr_debugfs_buf_load(struct file *file,
+                                        const char __user *ptr, size_t len,
+                                        loff_t *off)
+{
+       struct fpga_manager *mgr = file->private_data;
+       struct device *dev = &mgr->dev;
+       char *buf;
+       int ret = 0;
+
+       /* struct with information about the FPGA image to program. */
+       struct fpga_image_info info = {0};
+
+       /* flags indicates whether to do full or partial reconfiguration */
+       info.flags = mgr->flags;
+
+       ret = fpga_mgr_lock(mgr);
+       if (ret) {
+               dev_err(dev, "FPGA manager is busy\n");
+               return -EBUSY;
+       }
+
+       buf = vmalloc(len);
+       if (!buf) {
+               ret = -ENOMEM;
+               goto mgr_unlock;
+       }
+
+       if (copy_from_user(buf, ptr, len)) {
+               ret = -EFAULT;
+               goto free_buf;
+       }
+
+       info.buf = buf;
+       info.count = len;
+
+       ret = fpga_mgr_load(mgr, &info);
+       if (ret) {
+               dev_err(dev, "fpga_mgr_load returned with value %d\n\r", ret);
+               goto free_buf;
+       }
+
+free_buf:
+       vfree(buf);
+mgr_unlock:
+       fpga_mgr_unlock(mgr);
+
+       if (ret)
+               return ret;
+       else
+               return len;
+}
+
+static const struct file_operations fpga_mgr_ops_load = {
+       .open = simple_open,
+       .write = fpga_mgr_debugfs_buf_load,
+       .llseek = default_llseek,
+};
 #endif
 
 /**
@@ -811,6 +879,13 @@ int fpga_mgr_register(struct fpga_manager *mgr)
                debugfs_remove_recursive(mgr->dir);
                goto error_device;
        }
+
+       d = debugfs_create_file("load", 0644, parent, mgr,
+                               &fpga_mgr_ops_load);
+       if (!d) {
+               debugfs_remove_recursive(mgr->dir);
+               goto error_device;
+       }
 #endif
        dev_info(&mgr->dev, "%s registered\n", mgr->name);