From: Alan Tull <atull@xxxxxxxxxxxxxxxxxxxxx>
Implement DebugFS for the FPGA Manager Framework for
debugging and developmental use.
Enabled by CONFIG_FPGA_MGR_DEBUG_FS
Each FPGA gets its own directory such as
<debugfs>/fpga_manager/fpga0 and three files:
* [RW] flags = flags as defined in fpga-mgr.h
* [RW] firmware_name = write/read back name of FPGA image
firmware file to program
* [WO] image = write-only file for directly writing
fpga image w/o firmware layer
* [RW] config_complete_timeout_us = maximum for the FPGA to
go to the operating state after
programming
The debugfs is implemented in a separate fpga_mgr_debugfs.c
file, but the FPGA manager core is still built as one
module. Note the name change from fpga-mgr.ko to fpga_mgr.ko.
Signed-off-by: Alan Tull <atull@xxxxxxxxxx>
Signed-off-by: Matthew Gerlach <matthew.gerlach@xxxxxxxxxxxxxxx>
---
drivers/fpga/Kconfig | 7 ++
drivers/fpga/Makefile | 4 +-
drivers/fpga/fpga-mgr-debugfs.c | 221 ++++++++++++++++++++++++++++++++++++++++
drivers/fpga/fpga-mgr-debugfs.h | 22 ++++
drivers/fpga/fpga-mgr.c | 8 ++
include/linux/fpga/fpga-mgr.h | 3 +
6 files changed, 264 insertions(+), 1 deletion(-)
create mode 100644 drivers/fpga/fpga-mgr-debugfs.c
create mode 100644 drivers/fpga/fpga-mgr-debugfs.h
diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
index 1ebcef4..600924d 100644
--- a/drivers/fpga/Kconfig
+++ b/drivers/fpga/Kconfig
@@ -9,6 +9,13 @@ menuconfig FPGA
kernel. The FPGA framework adds a FPGA manager class and FPGA
manager drivers.
+config FPGA_MGR_DEBUG_FS
+ bool "FPGA Manager DebugFS"
+ depends on FPGA && DEBUG_FS
+ help
+ Say Y here if you want to expose a DebugFS interface for the
+ FPGA Manager Framework.
+
if FPGA
config FPGA_MGR_SOCFPGA
diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
index 7a2d73b..62910cc 100644
--- a/drivers/fpga/Makefile
+++ b/drivers/fpga/Makefile
@@ -4,7 +4,9 @@
#
# Core FPGA Manager Framework
-obj-$(CONFIG_FPGA) += fpga-mgr.o
+obj-$(CONFIG_FPGA) += fpga_mgr.o
+fpga_mgr-y := fpga-mgr.o
+fpga_mgr-$(CONFIG_FPGA_MGR_DEBUG_FS) += fpga-mgr-debugfs.o
# FPGA Manager Drivers
obj-$(CONFIG_FPGA_MGR_ALTERA_CVP) += altera-cvp.o
diff --git a/drivers/fpga/fpga-mgr-debugfs.c b/drivers/fpga/fpga-mgr-debugfs.c
new file mode 100644
index 0000000..f2fdf58
--- /dev/null
+++ b/drivers/fpga/fpga-mgr-debugfs.c
@@ -0,0 +1,221 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * FPGA Manager DebugFS
+ *
+ * Copyright (C) 2016-2018 Intel Corporation. All rights reserved.
+ */
+#include <linux/debugfs.h>
+#include <linux/fpga/fpga-mgr.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+
+static struct dentry *fpga_mgr_debugfs_root;
+
+struct fpga_mgr_debugfs {
+ struct dentry *debugfs_dir;
+ struct fpga_image_info *info;
+};
+
+static ssize_t fpga_mgr_firmware_write_file(struct file *file,
+ const char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ struct fpga_manager *mgr = file->private_data;
+ struct fpga_mgr_debugfs *debugfs = mgr->debugfs;
+ struct device *dev = &mgr->dev;
+ char *buf;
+ int ret;
+
+ ret = fpga_mgr_lock(mgr);
+ if (ret) {
+ dev_err(dev, "FPGA manager is busy\n");
+ return -EBUSY;
+ }
+
+ buf = devm_kzalloc(dev, count, GFP_KERNEL);
+ if (!buf) {
+ fpga_mgr_unlock(mgr);
+ return -ENOMEM;
+ }
+
+ if (copy_from_user(buf, user_buf, count)) {
+ fpga_mgr_unlock(mgr);
+ devm_kfree(dev, buf);
+ return -EFAULT;
+ }
+
+ buf[count] = 0;
+ if (buf[count - 1] == '\n')
+ buf[count - 1] = 0;
+
+ /* Release previous firmware name (if any). Save current one. */
+ if (debugfs->info->firmware_name)
+ devm_kfree(dev, debugfs->info->firmware_name);
+ debugfs->info->firmware_name = buf;
+
+ ret = fpga_mgr_load(mgr, debugfs->info);
+ if (ret)
+ dev_err(dev, "fpga_mgr_load returned with value %d\n", ret);
+
+ fpga_mgr_unlock(mgr);
+
+ return count;
+}
+
+static ssize_t fpga_mgr_firmware_read_file(struct file *file,
+ char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ struct fpga_manager *mgr = file->private_data;
+ struct fpga_mgr_debugfs *debugfs = mgr->debugfs;
+ char *buf;
+ int ret;
+
+ if (!debugfs->info->firmware_name)
+ return 0;
+
+ buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ ret = snprintf(buf, PAGE_SIZE, "%s\n", debugfs->info->firmware_name);
+ if (ret < 0) {
+ kfree(buf);
+ return ret;
+ }
+
+ ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
+ kfree(buf);
+
+ return ret;
+}
+
+static const struct file_operations fpga_mgr_firmware_fops = {
+ .open = simple_open,
+ .read = fpga_mgr_firmware_read_file,
+ .write = fpga_mgr_firmware_write_file,
+ .llseek = default_llseek,
+};
+
+static ssize_t fpga_mgr_image_write_file(struct file *file,
+ const char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ struct fpga_manager *mgr = file->private_data;
+ struct fpga_mgr_debugfs *debugfs = mgr->debugfs;
+ struct device *dev = &mgr->dev;
+ char *buf;
+ int ret;
+
+ dev_info(dev, "writing %zu bytes to %s\n", count, mgr->name);
+
+ ret = fpga_mgr_lock(mgr);
+ if (ret) {
+ dev_err(dev, "FPGA manager is busy\n");
+ return -EBUSY;
+ }
+
+ buf = kzalloc(count, GFP_KERNEL);
+ if (!buf) {
+ fpga_mgr_unlock(mgr);
+ return -ENOMEM;
+ }
+
+ if (copy_from_user(buf, user_buf, count)) {
+ fpga_mgr_unlock(mgr);
+ kfree(buf);
+ return -EFAULT;
+ }
+
+ /* If firmware interface was previously used, forget it. */
+ if (debugfs->info->firmware_name)
+ devm_kfree(dev, debugfs->info->firmware_name);
+ debugfs->info->firmware_name = NULL;
+
+ debugfs->info->buf = buf;
+ debugfs->info->count = count;
+
+ ret = fpga_mgr_load(mgr, debugfs->info);
+ if (ret)
+ dev_err(dev, "fpga_mgr_load returned with value %d\n", ret);
+
+ fpga_mgr_unlock(mgr);
+
+ debugfs->info->buf = NULL;
+ debugfs->info->count = 0;
+
+ kfree(buf);
+
+ return count;
+}
+
+static const struct file_operations fpga_mgr_image_fops = {
+ .open = simple_open,
+ .write = fpga_mgr_image_write_file,
+ .llseek = default_llseek,
+};
+
+void fpga_mgr_debugfs_add(struct fpga_manager *mgr)
+{
+ struct device *dev = &mgr->dev;
+ struct fpga_mgr_debugfs *debugfs;
+ struct fpga_image_info *info;
+
+ if (!fpga_mgr_debugfs_root)
+ return;
+
+ debugfs = kzalloc(sizeof(*debugfs), GFP_KERNEL);
+ if (!debugfs)
+ return;
+
+ info = fpga_image_info_alloc(dev);
+ if (!info) {
+ kfree(debugfs);
+ return;
+ }
+ debugfs->info = info;
+
+ debugfs->debugfs_dir = debugfs_create_dir(dev_name(dev),
+ fpga_mgr_debugfs_root);
+
+ debugfs_create_file("firmware_name", 0600, debugfs->debugfs_dir, mgr,
+ &fpga_mgr_firmware_fops);
+
+ debugfs_create_file("image", 0200, debugfs->debugfs_dir, mgr,
+ &fpga_mgr_image_fops);
+
+ debugfs_create_u32("flags", 0600, debugfs->debugfs_dir, &info->flags);
+
+ debugfs_create_u32("config_complete_timeout_us", 0600,
+ debugfs->debugfs_dir,
+ &info->config_complete_timeout_us);
+
+ mgr->debugfs = debugfs;
+}
+
+void fpga_mgr_debugfs_remove(struct fpga_manager *mgr)
+{
+ struct fpga_mgr_debugfs *debugfs = mgr->debugfs;
+
+ if (!fpga_mgr_debugfs_root)
+ return;
+
+ debugfs_remove_recursive(debugfs->debugfs_dir);
+
+ /* this function also frees debugfs->info->firmware_name */
+ fpga_image_info_free(debugfs->info);
+
+ kfree(debugfs);
+}
+
+void fpga_mgr_debugfs_init(void)
+{
+ fpga_mgr_debugfs_root = debugfs_create_dir("fpga_manager", NULL);
+ if (!fpga_mgr_debugfs_root)
+ pr_warn("fpga_mgr: Failed to create debugfs root\n");
+}
+
+void fpga_mgr_debugfs_uninit(void)
+{
+ debugfs_remove_recursive(fpga_mgr_debugfs_root);
+}
diff --git a/drivers/fpga/fpga-mgr-debugfs.h b/drivers/fpga/fpga-mgr-debugfs.h
new file mode 100644
index 0000000..17cd3eb
--- /dev/null
+++ b/drivers/fpga/fpga-mgr-debugfs.h
@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#ifndef _LINUX_FPGA_MGR_DEBUGFS_H
+#define _LINUX_FPGA_MGR_DEBUGFS_H
+
+#if IS_ENABLED(CONFIG_FPGA_MGR_DEBUG_FS)
+
+void fpga_mgr_debugfs_add(struct fpga_manager *mgr);
+void fpga_mgr_debugfs_remove(struct fpga_manager *mgr);
+void fpga_mgr_debugfs_init(void);
+void fpga_mgr_debugfs_uninit(void);
+
+#else
+
+void fpga_mgr_debugfs_add(struct fpga_manager *mgr) {}
+void fpga_mgr_debugfs_remove(struct fpga_manager *mgr) {}
+void fpga_mgr_debugfs_init(void) {}
+void fpga_mgr_debugfs_uninit(void) {}
+
+#endif /* CONFIG_FPGA_MGR_DEBUG_FS */
+
+#endif /*_LINUX_FPGA_MGR_DEBUGFS_H */
diff --git a/drivers/fpga/fpga-mgr.c b/drivers/fpga/fpga-mgr.c
index c8684bc..66eb6f6 100644
--- a/drivers/fpga/fpga-mgr.c
+++ b/drivers/fpga/fpga-mgr.c
@@ -17,6 +17,7 @@
#include <linux/slab.h>
#include <linux/scatterlist.h>
#include <linux/highmem.h>
+#include "fpga-mgr-debugfs.h"
static DEFINE_IDA(fpga_mgr_ida);
static struct class *fpga_mgr_class;
@@ -698,6 +699,8 @@ int fpga_mgr_register(struct fpga_manager *mgr)
if (ret)
goto error_device;
+ fpga_mgr_debugfs_add(mgr);
+
dev_info(&mgr->dev, "%s registered\n", mgr->name);
return 0;
@@ -722,6 +725,8 @@ void fpga_mgr_unregister(struct fpga_manager *mgr)
{
dev_info(&mgr->dev, "%s %s\n", __func__, mgr->name);
+ fpga_mgr_debugfs_remove(mgr);
+
/*
* If the low level driver provides a method for putting fpga into
* a desired state upon unregister, do it.
@@ -748,11 +753,14 @@ static int __init fpga_mgr_class_init(void)
fpga_mgr_class->dev_groups = fpga_mgr_groups;
fpga_mgr_class->dev_release = fpga_mgr_dev_release;
+ fpga_mgr_debugfs_init();
+
return 0;
}
static void __exit fpga_mgr_class_exit(void)
{
+ fpga_mgr_debugfs_uninit();
class_destroy(fpga_mgr_class);
ida_destroy(&fpga_mgr_ida);
}
diff --git a/include/linux/fpga/fpga-mgr.h b/include/linux/fpga/fpga-mgr.h
index 777c502..e8f2159 100644
--- a/include/linux/fpga/fpga-mgr.h
+++ b/include/linux/fpga/fpga-mgr.h
@@ -170,6 +170,9 @@ struct fpga_manager {
struct fpga_compat_id *compat_id;
const struct fpga_manager_ops *mops;
void *priv;
+#if IS_ENABLED(CONFIG_FPGA_MGR_DEBUG_FS)
+ void *debugfs;
+#endif
};
#define to_fpga_manager(d) container_of(d, struct fpga_manager, dev)
--
2.7.4
