fpga: mgr: add status for fpga-manager

This patch adds status sysfs interface for fpga manager, it's a
read only interface which allows user to get fpga manager status,
including full/partial reconfiguration error and other status
information. It adds a status callback to fpga_manager_ops too,
allows each fpga_manager driver to define its own method to
collect latest status from hardware.

The following sysfs file is created:
* /sys/class/fpga_manager/<fpga>/status
  Return status of fpga manager, including reconfiguration errors.

Signed-off-by: Wu Hao <hao.wu@intel.com>
Acked-by: Alan Tull <atull@kernel.org>
Acked-by: Moritz Fischer <mdf@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/Documentation/ABI/testing/sysfs-class-fpga-manager b/Documentation/ABI/testing/sysfs-class-fpga-manager
index 23056c5..5284fa3 100644 (file)
--- a/Documentation/ABI/testing/sysfs-class-fpga-manager
+++ b/Documentation/ABI/testing/sysfs-class-fpga-manager
@@ -35,3 +35,27 @@ Description: Read fpga manager state as a string.
                * write complete        = Doing post programming steps
                * write complete error  = Error while doing post programming
                * operating             = FPGA is programmed and operating
+
+What:          /sys/class/fpga_manager/<fpga>/status
+Date:          June 2018
+KernelVersion: 4.19
+Contact:       Wu Hao <hao.wu@intel.com>
+Description:   Read fpga manager status as a string.
+               If FPGA programming operation fails, it could be caused by crc
+               error or incompatible bitstream image. The intent of this
+               interface is to provide more detailed information for FPGA
+               programming errors to userspace. This is a list of strings for
+               the supported status.
+
+               * reconfig operation error      - invalid operations detected by
+                                                 reconfiguration hardware.
+                                                 e.g. start reconfiguration
+                                                 with errors not cleared
+               * reconfig CRC error            - CRC error detected by
+                                                 reconfiguration hardware.
+               * reconfig incompatible image   - reconfiguration image is
+                                                 incompatible with hardware
+               * reconfig IP protocol error    - protocol errors detected by
+                                                 reconfiguration hardware
+               * reconfig fifo overflow error  - FIFO overflow detected by
+                                                 reconfiguration hardware

diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
index c1564cf..a41b07e 100644 (file)
--- a/drivers/fpga/fpga-mgr.c
+++ b/drivers/fpga/fpga-mgr.c
@@ -406,12 +406,40 @@ static ssize_t state_show(struct device *dev,
        return sprintf(buf, "%s\n", state_str[mgr->state]);
 }
 
+static ssize_t status_show(struct device *dev,
+                          struct device_attribute *attr, char *buf)
+{
+       struct fpga_manager *mgr = to_fpga_manager(dev);
+       u64 status;
+       int len = 0;
+
+       if (!mgr->mops->status)
+               return -ENOENT;
+
+       status = mgr->mops->status(mgr);
+
+       if (status & FPGA_MGR_STATUS_OPERATION_ERR)
+               len += sprintf(buf + len, "reconfig operation error\n");
+       if (status & FPGA_MGR_STATUS_CRC_ERR)
+               len += sprintf(buf + len, "reconfig CRC error\n");
+       if (status & FPGA_MGR_STATUS_INCOMPATIBLE_IMAGE_ERR)
+               len += sprintf(buf + len, "reconfig incompatible image\n");
+       if (status & FPGA_MGR_STATUS_IP_PROTOCOL_ERR)
+               len += sprintf(buf + len, "reconfig IP protocol error\n");
+       if (status & FPGA_MGR_STATUS_FIFO_OVERFLOW_ERR)
+               len += sprintf(buf + len, "reconfig fifo overflow error\n");
+
+       return len;
+}
+
 static DEVICE_ATTR_RO(name);
 static DEVICE_ATTR_RO(state);
+static DEVICE_ATTR_RO(status);
 
 static struct attribute *fpga_mgr_attrs[] = {
        &dev_attr_name.attr,
        &dev_attr_state.attr,
+       &dev_attr_status.attr,
        NULL,
 };
 ATTRIBUTE_GROUPS(fpga_mgr);

diff --git a/include/linux/fpga/fpga-mgr.h b/include/linux/fpga/fpga-mgr.h
index 3eb6b9d..e249b72 100644 (file)
--- a/include/linux/fpga/fpga-mgr.h
+++ b/include/linux/fpga/fpga-mgr.h
@@ -101,6 +101,7 @@ struct fpga_image_info {
  * struct fpga_manager_ops - ops for low level fpga manager drivers
  * @initial_header_size: Maximum number of bytes that should be passed into write_init
  * @state: returns an enum value of the FPGA's state
+ * @status: returns status of the FPGA, including reconfiguration error code
  * @write_init: prepare the FPGA to receive confuration data
  * @write: write count bytes of configuration data to the FPGA
  * @write_sg: write the scatter list of configuration data to the FPGA
@@ -115,6 +116,7 @@ struct fpga_image_info {
 struct fpga_manager_ops {
        size_t initial_header_size;
        enum fpga_mgr_states (*state)(struct fpga_manager *mgr);
+       u64 (*status)(struct fpga_manager *mgr);
        int (*write_init)(struct fpga_manager *mgr,
                          struct fpga_image_info *info,
                          const char *buf, size_t count);
@@ -126,6 +128,13 @@ struct fpga_manager_ops {
        const struct attribute_group **groups;
 };
 
+/* FPGA manager status: Partial/Full Reconfiguration errors */
+#define FPGA_MGR_STATUS_OPERATION_ERR          BIT(0)
+#define FPGA_MGR_STATUS_CRC_ERR                        BIT(1)
+#define FPGA_MGR_STATUS_INCOMPATIBLE_IMAGE_ERR BIT(2)
+#define FPGA_MGR_STATUS_IP_PROTOCOL_ERR                BIT(3)
+#define FPGA_MGR_STATUS_FIFO_OVERFLOW_ERR      BIT(4)
+
 /**
  * struct fpga_manager - fpga manager structure
  * @name: name of low level fpga manager