From: Russ Weight <russell.h.weight@xxxxxxxxx>
Extend the FPGA Security Manager class driver to include
an update/error sysfs node that can be read for error
information when a secure update fails.
Signed-off-by: Russ Weight <russell.h.weight@xxxxxxxxx>
Reviewed-by: Tom Rix <trix@xxxxxxxxxx>
Signed-off-by: Moritz Fischer <mdf@xxxxxxxxxx>
---
.../ABI/testing/sysfs-class-fpga-sec-mgr | 17 ++++
drivers/fpga/fpga-sec-mgr.c | 83 ++++++++++++++++---
include/linux/fpga/fpga-sec-mgr.h | 1 +
3 files changed, 89 insertions(+), 12 deletions(-)
diff --git a/Documentation/ABI/testing/sysfs-class-fpga-sec-mgr b/Documentation/ABI/testing/sysfs-class-fpga-sec-mgr
index b962ad2cf18d..24890d04521f 100644
--- a/Documentation/ABI/testing/sysfs-class-fpga-sec-mgr
+++ b/Documentation/ABI/testing/sysfs-class-fpga-sec-mgr
@@ -27,3 +27,20 @@ Description: Read-only. Returns a string describing the current
programming. Userspace code can poll on this file,
as it will be signaled by sysfs_notify() on each
state change.
+
+What: /sys/class/fpga_sec_mgr/fpga_secX/update/error
+Date: June 2021
+KernelVersion: 5.14
+Contact: Russ Weight <russell.h.weight@xxxxxxxxx>
+Description: Read-only. Returns a string describing the failure
+ of a secure update. This string will be in the form
+ of <STATUS>:<ERROR>, where <STATUS> will be one of
+ the status strings described for the status sysfs
+ file and <ERROR> will be one of the following:
+ hw-error, timeout, user-abort, device-busy,
+ invalid-file-size, read-write-error, flash-wearout,
+ file-read-error. The error sysfs file is only
+ meaningful when the secure update engine is in the
+ idle state. If this file is read while a secure
+ update is in progress, then the read will fail with
+ EBUSY.
diff --git a/drivers/fpga/fpga-sec-mgr.c b/drivers/fpga/fpga-sec-mgr.c
index 19f60048a965..903385779a1f 100644
--- a/drivers/fpga/fpga-sec-mgr.c
+++ b/drivers/fpga/fpga-sec-mgr.c
@@ -30,10 +30,16 @@ static void update_progress(struct fpga_sec_mgr *smgr,
sysfs_notify(&smgr->dev.kobj, "update", "status");
}
+static void fpga_sec_set_error(struct fpga_sec_mgr *smgr, enum fpga_sec_err err_code)
+{
+ smgr->err_state = smgr->progress;
+ smgr->err_code = err_code;
+}
+
static void fpga_sec_dev_error(struct fpga_sec_mgr *smgr,
enum fpga_sec_err err_code)
{
- smgr->err_code = err_code;
+ fpga_sec_set_error(smgr, err_code);
smgr->sops->cancel(smgr);
}
@@ -56,7 +62,7 @@ static void fpga_sec_mgr_update(struct work_struct *work)
get_device(&smgr->dev);
if (request_firmware(&fw, smgr->filename, &smgr->dev)) {
- smgr->err_code = FPGA_SEC_ERR_FILE_READ;
+ fpga_sec_set_error(smgr, FPGA_SEC_ERR_FILE_READ);
goto idle_exit;
}
@@ -64,7 +70,7 @@ static void fpga_sec_mgr_update(struct work_struct *work)
smgr->remaining_size = fw->size;
if (!try_module_get(smgr->dev.parent->driver->owner)) {
- smgr->err_code = FPGA_SEC_ERR_BUSY;
+ fpga_sec_set_error(smgr, FPGA_SEC_ERR_BUSY);
goto release_fw_exit;
}
@@ -122,24 +128,76 @@ static const char * const sec_mgr_prog_str[] = {
[FPGA_SEC_PROG_PROGRAMMING] = "programming"
};
-static ssize_t
-status_show(struct device *dev, struct device_attribute *attr, char *buf)
+static const char * const sec_mgr_err_str[] = {
+ [FPGA_SEC_ERR_NONE] = "none",
+ [FPGA_SEC_ERR_HW_ERROR] = "hw-error",
+ [FPGA_SEC_ERR_TIMEOUT] = "timeout",
+ [FPGA_SEC_ERR_CANCELED] = "user-abort",
+ [FPGA_SEC_ERR_BUSY] = "device-busy",
+ [FPGA_SEC_ERR_INVALID_SIZE] = "invalid-file-size",
+ [FPGA_SEC_ERR_RW_ERROR] = "read-write-error",
+ [FPGA_SEC_ERR_WEAROUT] = "flash-wearout",
+ [FPGA_SEC_ERR_FILE_READ] = "file-read-error"
+};
+
+static const char *sec_progress(struct device *dev, enum fpga_sec_prog prog)
{
- struct fpga_sec_mgr *smgr = to_sec_mgr(dev);
const char *status = "unknown-status";
- enum fpga_sec_prog progress;
- progress = smgr->progress;
- if (progress < FPGA_SEC_PROG_MAX)
- status = sec_mgr_prog_str[progress];
+ if (prog < FPGA_SEC_PROG_MAX)
+ status = sec_mgr_prog_str[prog];
else
dev_err(dev, "Invalid status during secure update: %d\n",
- progress);
+ prog);
+
+ return status;
+}
+
+static const char *sec_error(struct device *dev, enum fpga_sec_err err_code)
+{
+ const char *error = "unknown-error";
+
+ if (err_code < FPGA_SEC_ERR_MAX)
+ error = sec_mgr_err_str[err_code];
+ else
+ dev_err(dev, "Invalid error code during secure update: %d\n",
+ err_code);
+
+ return error;
+}
+
+static ssize_t
+status_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct fpga_sec_mgr *smgr = to_sec_mgr(dev);
- return sysfs_emit(buf, "%s\n", status);
+ return sysfs_emit(buf, "%s\n", sec_progress(dev, smgr->progress));
}
static DEVICE_ATTR_RO(status);
+static ssize_t
+error_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct fpga_sec_mgr *smgr = to_sec_mgr(dev);
+ int ret;
+
+ mutex_lock(&smgr->lock);
+
+ if (smgr->progress != FPGA_SEC_PROG_IDLE)
+ ret = -EBUSY;
+ else if (!smgr->err_code)
+ ret = 0;
+ else
+ ret = sysfs_emit(buf, "%s:%s\n",
+ sec_progress(dev, smgr->err_state),
+ sec_error(dev, smgr->err_code));
+
+ mutex_unlock(&smgr->lock);
+
+ return ret;
+}
+static DEVICE_ATTR_RO(error);
+
static ssize_t filename_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
@@ -175,6 +233,7 @@ static DEVICE_ATTR_WO(filename);
static struct attribute *sec_mgr_update_attrs[] = {
&dev_attr_filename.attr,
&dev_attr_status.attr,
+ &dev_attr_error.attr,
NULL,
};
diff --git a/include/linux/fpga/fpga-sec-mgr.h b/include/linux/fpga/fpga-sec-mgr.h
index 978ab98ffac5..6b7b8a3d6aac 100644
--- a/include/linux/fpga/fpga-sec-mgr.h
+++ b/include/linux/fpga/fpga-sec-mgr.h
@@ -70,6 +70,7 @@ struct fpga_sec_mgr {
const u8 *data; /* pointer to update data */
u32 remaining_size; /* size remaining to transfer */
enum fpga_sec_prog progress;
+ enum fpga_sec_prog err_state; /* progress state at time of failure */
enum fpga_sec_err err_code; /* security manager error code */
bool driver_unload;
void *priv;
--
2.31.1
