@@ -198,8 +198,12 @@ device data.
- The contents of the device firmware's capabilities buffer. Useful to
determine the current state and configuration of the device.
-Users can request an immediate capture of a snapshot via the
-``DEVLINK_CMD_REGION_NEW``
+Both the ``nvm-flash`` and ``shadow-ram`` regions can be accessed without a
+snapshot. The ``device-caps`` region requires a snapshot as the contents are
+sent by firmware and can't be split into separate reads.
+
+Users can request an immediate capture of a snapshot for all three regions
+via the ``DEVLINK_CMD_REGION_NEW`` command.
.. code:: shell
@@ -1687,6 +1687,73 @@ static int ice_devlink_nvm_snapshot(struct devlink *devlink,
return 0;
}
+/**
+ * ice_devlink_nvm_read - Read a portion of NVM flash contents
+ * @devlink: the devlink instance
+ * @ops: the devlink region to snapshot
+ * @extack: extended ACK response structure
+ * @offset: the offset to start at
+ * @size: the amount to read
+ * @data: the data buffer to read into
+ *
+ * This function is called in response to DEVLINK_CMD_REGION_READ to directly
+ * read a section of the NVM contents.
+ *
+ * It reads from either the nvm-flash or shadow-ram region contents.
+ *
+ * @returns zero on success, and updates the data pointer. Returns a non-zero
+ * error code on failure.
+ */
+static int ice_devlink_nvm_read(struct devlink *devlink,
+ const struct devlink_region_ops *ops,
+ struct netlink_ext_ack *extack,
+ u64 offset, u32 size, u8 *data)
+{
+ struct ice_pf *pf = devlink_priv(devlink);
+ struct device *dev = ice_pf_to_dev(pf);
+ struct ice_hw *hw = &pf->hw;
+ bool read_shadow_ram;
+ u64 nvm_size;
+ int status;
+
+ if (ops == &ice_nvm_region_ops) {
+ read_shadow_ram = false;
+ nvm_size = hw->flash.flash_size;
+ } else if (ops == &ice_sram_region_ops) {
+ read_shadow_ram = true;
+ nvm_size = hw->flash.sr_words * 2u;
+ } else {
+ NL_SET_ERR_MSG_MOD(extack, "Unexpected region in snapshot function");
+ return -EOPNOTSUPP;
+ }
+
+ if (offset + size >= nvm_size) {
+ NL_SET_ERR_MSG_MOD(extack, "Cannot read beyond the region size");
+ return -ERANGE;
+ }
+
+ status = ice_acquire_nvm(hw, ICE_RES_READ);
+ if (status) {
+ dev_dbg(dev, "ice_acquire_nvm failed, err %d aq_err %d\n",
+ status, hw->adminq.sq_last_status);
+ NL_SET_ERR_MSG_MOD(extack, "Failed to acquire NVM semaphore");
+ return -EIO;
+ }
+
+ status = ice_read_flat_nvm(hw, (u32)offset, &size, data,
+ read_shadow_ram);
+ if (status) {
+ dev_dbg(dev, "ice_read_flat_nvm failed after reading %u bytes, err %d aq_err %d\n",
+ size, status, hw->adminq.sq_last_status);
+ NL_SET_ERR_MSG_MOD(extack, "Failed to read NVM contents");
+ ice_release_nvm(hw);
+ return -EIO;
+ }
+ ice_release_nvm(hw);
+
+ return 0;
+}
+
/**
* ice_devlink_devcaps_snapshot - Capture snapshot of device capabilities
* @devlink: the devlink instance
@@ -1735,12 +1802,14 @@ static const struct devlink_region_ops ice_nvm_region_ops = {
.name = "nvm-flash",
.destructor = vfree,
.snapshot = ice_devlink_nvm_snapshot,
+ .read = ice_devlink_nvm_read,
};
static const struct devlink_region_ops ice_sram_region_ops = {
.name = "shadow-ram",
.destructor = vfree,
.snapshot = ice_devlink_nvm_snapshot,
+ .read = ice_devlink_nvm_read,
};
static const struct devlink_region_ops ice_devcaps_region_ops = {
Implement the .read handler for the NVM and Shadow RAM regions. This enables user space to read a small chunk of the flash without needing the overhead of creating a full snapshot. Update the documentation for ice to detail which regions have direct read support. Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> --- Changes since v1 * Update documentation for ice.rst Documentation/networking/devlink/ice.rst | 8 ++- drivers/net/ethernet/intel/ice/ice_devlink.c | 69 ++++++++++++++++++++ 2 files changed, 75 insertions(+), 2 deletions(-)