ice: support immediate firmware activation via devlink reload

The ice hardware contains an embedded chip with firmware which can be
updated using devlink flash. The firmware which runs on this chip is
referred to as the Embedded Management Processor firmware (EMP
firmware).

Activating the new firmware image currently requires that the system be
rebooted. This is not ideal as rebooting the system can cause unwanted
downtime.

In practical terms, activating the firmware does not always require a
full system reboot. In many cases it is possible to activate the EMP
firmware immediately. There are a couple of different scenarios to
cover.

 * The EMP firmware itself can be reloaded by issuing a special update
   to the device called an Embedded Management Processor reset (EMP
   reset). This reset causes the device to reset and reload the EMP
   firmware.

 * PCI configuration changes are only reloaded after a cold PCIe reset.
   Unfortunately there is no generic way to trigger this for a PCIe
   device without a system reboot.

When performing a flash update, firmware is capable of responding with
some information about the specific update requirements.

The driver updates the flash by programming a secondary inactive bank
with the contents of the new image, and then issuing a command to
request to switch the active bank starting from the next load.

The response to the final command for updating the inactive NVM flash
bank includes an indication of the minimum reset required to fully
update the device. This can be one of the following:

 * A full power on is required
 * A cold PCIe reset is required
 * An EMP reset is required

The response to the command to switch flash banks includes an indication
of whether or not the firmware will allow an EMP reset request.

For most updates, an EMP reset is sufficient to load the new EMP
firmware without issues. In some cases, this reset is not sufficient
because the PCI configuration space has changed. When this could cause
incompatibility with the new EMP image, the firmware is capable of
rejecting the EMP reset request.

Add logic to ice_fw_update.c to handle the response data flash update
AdminQ commands.

For the reset level, issue a devlink status notification informing the
user of how to complete the update with a simple suggestion like
"Activate new firmware by rebooting the system".

Cache the status of whether or not firmware will restrict the EMP reset
for use in implementing devlink reload.

Implement support for devlink reload with the "fw_activate" flag. This
allows user space to request the firmware be activated immediately.

For the .reload_down handler, we will issue a request for the EMP reset
using the appropriate firmware AdminQ command. If we know that the
firmware will not allow an EMP reset, simply exit with a suitable
netlink extended ACK message indicating that the EMP reset is not
available.

For the .reload_up handler, simply wait until the driver has finished
resetting. Logic to handle processing of an EMP reset already exists in
the driver as part of its reset and rebuild flows.

Implement support for the devlink reload interface with the
"fw_activate" action. This allows userspace to request activation of
firmware without a reboot.

Note that support for indicating the required reset and EMP reset
restriction is not supported on old versions of firmware. The driver can
determine if the two features are supported by checking the device
capabilities report. I confirmed support has existed since at least
version 5.5.2 as reported by the 'fw.mgmt' version. Support to issue the
EMP reset request has existed in all version of the EMP firmware for the
ice hardware.

Check the device capabilities report to determine whether or not the
indications are reported by the running firmware. If the reset
requirement indication is not supported, always assume a full power on
is necessary. If the reset restriction capability is not supported,
always assume the EMP reset is available.

Users can verify if the EMP reset has activated the firmware by using
the devlink info report to check that the 'running' firmware version has
updated. For example a user might do the following:

 # Check current version
 $ devlink dev info

 # Update the device
 $ devlink dev flash pci/0000:af:00.0 file firmware.bin

 # Confirm stored version updated
 $ devlink dev info

 # Reload to activate new firmware
 $ devlink dev reload pci/0000:af:00.0 action fw_activate

 # Confirm running version updated
 $ devlink dev info

Finally, this change does *not* implement basic driver-only reload
support. I did look into trying to do this. However, it requires
significant refactor of how the ice driver probes and loads everything.
The ice driver probe and allocation flows were not designed with such
a reload in mind. Refactoring the flow to support this is beyond the
scope of this change.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Gurucharan G <gurucharanx.g@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

1 files changed, 158 insertions, 23 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice_fw_update.c b/drivers/net/ethernet/intel/ice/ice_fw_update.c
index 1f8e0e5d5660..665a344fb9c0 100644
--- a/drivers/net/ethernet/intel/ice/ice_fw_update.c
+++ b/drivers/net/ethernet/intel/ice/ice_fw_update.c
@@ -16,6 +16,18 @@ struct ice_fwu_priv {
 
 	/* Track which NVM banks to activate at the end of the update */
 	u8 activate_flags;
+
+	/* Track the firmware response of the required reset to complete the
+	 * flash update.
+	 *
+	 * 0 - ICE_AQC_NVM_POR_FLAG - A full power on is required
+	 * 1 - ICE_AQC_NVM_PERST_FLAG - A cold PCIe reset is required
+	 * 2 - ICE_AQC_NVM_EMPR_FLAG - An EMP reset is required
+	 */
+	u8 reset_level;
+
+	/* Track if EMP reset is available */
+	u8 emp_reset_available;
 };
 
 /**
@@ -257,6 +269,7 @@ ice_send_component_table(struct pldmfw *context, struct pldmfw_component *compon
  * @block_size: size of the block to write, up to 4k
  * @block: pointer to block of data to write
  * @last_cmd: whether this is the last command
+ * @reset_level: storage for reset level required
  * @extack: netlink extended ACK structure
  *
  * Write a block of data to a flash module, and await for the completion
@@ -264,12 +277,19 @@ ice_send_component_table(struct pldmfw *context, struct pldmfw_component *compon
  *
  * Note this function assumes the caller has acquired the NVM resource.
  *
+ * On successful return, reset level indicates the device reset required to
+ * complete the update.
+ *
+ *   0 - ICE_AQC_NVM_POR_FLAG - A full power on is required
+ *   1 - ICE_AQC_NVM_PERST_FLAG - A cold PCIe reset is required
+ *   2 - ICE_AQC_NVM_EMPR_FLAG - An EMP reset is required
+ *
  * Returns: zero on success, or a negative error code on failure.
  */
 static int
 ice_write_one_nvm_block(struct ice_pf *pf, u16 module, u32 offset,
 			u16 block_size, u8 *block, bool last_cmd,
-			struct netlink_ext_ack *extack)
+			u8 *reset_level, struct netlink_ext_ack *extack)
 {
 	u16 completion_module, completion_retval;
 	struct device *dev = ice_pf_to_dev(pf);
@@ -335,6 +355,24 @@ ice_write_one_nvm_block(struct ice_pf *pf, u16 module, u32 offset,
 		return -EIO;
 	}
 
+	/* For the last command to write the NVM bank, newer versions of
+	 * firmware indicate the required level of reset to complete
+	 * activation of firmware. If the firmware supports this, cache the
+	 * response for indicating to the user later. Otherwise, assume that
+	 * a full power cycle is required.
+	 */
+	if (reset_level && last_cmd && module == ICE_SR_1ST_NVM_BANK_PTR) {
+		if (hw->dev_caps.common_cap.pcie_reset_avoidance) {
+			*reset_level = (event.desc.params.nvm.cmd_flags &
+					ICE_AQC_NVM_RESET_LVL_M);
+			dev_dbg(dev, "Firmware reported required reset level as %u\n",
+				*reset_level);
+		} else {
+			*reset_level = ICE_AQC_NVM_POR_FLAG;
+			dev_dbg(dev, "Firmware doesn't support indicating required reset level. Assuming a power cycle is required\n");
+		}
+	}
+
 	return 0;
 }
 
@@ -345,6 +383,7 @@ ice_write_one_nvm_block(struct ice_pf *pf, u16 module, u32 offset,
  * @component: the name of the component being updated
  * @image: buffer of image data to write to the NVM
  * @length: length of the buffer
+ * @reset_level: storage for reset level required
  * @extack: netlink extended ACK structure
  *
  * Loop over the data for a given NVM module and program it in 4 Kb
@@ -357,7 +396,7 @@ ice_write_one_nvm_block(struct ice_pf *pf, u16 module, u32 offset,
  */
 static int
 ice_write_nvm_module(struct ice_pf *pf, u16 module, const char *component,
-		     const u8 *image, u32 length,
+		     const u8 *image, u32 length, u8 *reset_level,
 		     struct netlink_ext_ack *extack)
 {
 	struct device *dev = ice_pf_to_dev(pf);
@@ -391,7 +430,8 @@ ice_write_nvm_module(struct ice_pf *pf, u16 module, const char *component,
 		memcpy(block, image + offset, block_size);
 
 		err = ice_write_one_nvm_block(pf, module, offset, block_size,
-					      block, last_cmd, extack);
+					      block, last_cmd, reset_level,
+					      extack);
 		if (err)
 			break;
 
@@ -507,6 +547,7 @@ out_notify_devlink:
  * ice_switch_flash_banks - Tell firmware to switch NVM banks
  * @pf: Pointer to the PF data structure
  * @activate_flags: flags used for the activation command
+ * @emp_reset_available: on return, indicates if EMP reset is available
  * @extack: netlink extended ACK structure
  *
  * Notify firmware to activate the newly written flash banks, and wait for the
@@ -514,18 +555,20 @@ out_notify_devlink:
  *
  * Returns: zero on success or an error code on failure.
  */
-static int ice_switch_flash_banks(struct ice_pf *pf, u8 activate_flags,
-				  struct netlink_ext_ack *extack)
+static int
+ice_switch_flash_banks(struct ice_pf *pf, u8 activate_flags,
+		       u8 *emp_reset_available, struct netlink_ext_ack *extack)
 {
 	struct device *dev = ice_pf_to_dev(pf);
 	struct ice_rq_event_info event;
 	struct ice_hw *hw = &pf->hw;
 	u16 completion_retval;
+	u8 response_flags;
 	int err;
 
 	memset(&event, 0, sizeof(event));
 
-	err = ice_nvm_write_activate(hw, activate_flags);
+	err = ice_nvm_write_activate(hw, activate_flags, &response_flags);
 	if (err) {
 		dev_err(dev, "Failed to switch active flash banks, err %d aq_err %s\n",
 			err, ice_aq_str(hw->adminq.sq_last_status));
@@ -533,6 +576,22 @@ static int ice_switch_flash_banks(struct ice_pf *pf, u8 activate_flags,
 		return -EIO;
 	}
 
+	/* Newer versions of firmware have support to indicate whether an EMP
+	 * reset to reload firmware is available. For older firmware, EMP
+	 * reset is always available.
+	 */
+	if (emp_reset_available) {
+		if (hw->dev_caps.common_cap.reset_restrict_support) {
+			*emp_reset_available = response_flags & ICE_AQC_NVM_EMPR_ENA;
+			dev_dbg(dev, "Firmware indicated that EMP reset is %s\n",
+				*emp_reset_available ?
+				"available" : "not available");
+		} else {
+			*emp_reset_available = ICE_AQC_NVM_EMPR_ENA;
+			dev_dbg(dev, "Firmware does not support restricting EMP reset availability\n");
+		}
+	}
+
 	err = ice_aq_wait_for_event(pf, ice_aqc_opc_nvm_write_activate, 30 * HZ,
 				    &event);
 	if (err) {
@@ -573,6 +632,7 @@ ice_flash_component(struct pldmfw *context, struct pldmfw_component *component)
 	struct netlink_ext_ack *extack = priv->extack;
 	struct ice_pf *pf = priv->pf;
 	const char *name;
+	u8 *reset_level;
 	u16 module;
 	u8 flag;
 	int err;
@@ -581,16 +641,19 @@ ice_flash_component(struct pldmfw *context, struct pldmfw_component *component)
 	case NVM_COMP_ID_OROM:
 		module = ICE_SR_1ST_OROM_BANK_PTR;
 		flag = ICE_AQC_NVM_ACTIV_SEL_OROM;
+		reset_level = NULL;
 		name = "fw.undi";
 		break;
 	case NVM_COMP_ID_NVM:
 		module = ICE_SR_1ST_NVM_BANK_PTR;
 		flag = ICE_AQC_NVM_ACTIV_SEL_NVM;
+		reset_level = &priv->reset_level;
 		name = "fw.mgmt";
 		break;
 	case NVM_COMP_ID_NETLIST:
 		module = ICE_SR_NETLIST_BANK_PTR;
 		flag = ICE_AQC_NVM_ACTIV_SEL_NETLIST;
+		reset_level = NULL;
 		name = "fw.netlist";
 		break;
 	default:
@@ -610,7 +673,8 @@ ice_flash_component(struct pldmfw *context, struct pldmfw_component *component)
 		return err;
 
 	return ice_write_nvm_module(pf, module, name, component->component_data,
-				    component->component_size, extack);
+				    component->component_size, reset_level,
+				    extack);
 }
 
 /**
@@ -628,9 +692,48 @@ static int ice_finalize_update(struct pldmfw *context)
 	struct ice_fwu_priv *priv = container_of(context, struct ice_fwu_priv, context);
 	struct netlink_ext_ack *extack = priv->extack;
 	struct ice_pf *pf = priv->pf;
+	struct devlink *devlink;
+	int err;
 
 	/* Finally, notify firmware to activate the written NVM banks */
-	return ice_switch_flash_banks(pf, priv->activate_flags, extack);
+	err = ice_switch_flash_banks(pf, priv->activate_flags,
+				     &priv->emp_reset_available, extack);
+	if (err)
+		return err;
+
+	devlink = priv_to_devlink(pf);
+
+	/* If the required reset is EMPR, but EMPR is disabled, report that
+	 * a reboot is required instead.
+	 */
+	if (priv->reset_level == ICE_AQC_NVM_EMPR_FLAG &&
+	    !priv->emp_reset_available) {
+		dev_dbg(ice_pf_to_dev(pf), "Firmware indicated EMP reset as sufficient, but EMP reset is disabled\n");
+		priv->reset_level = ICE_AQC_NVM_PERST_FLAG;
+	}
+
+	switch (priv->reset_level) {
+	case ICE_AQC_NVM_EMPR_FLAG:
+		devlink_flash_update_status_notify(devlink,
+						   "Activate new firmware by devlink reload",
+						   NULL, 0, 0);
+		break;
+	case ICE_AQC_NVM_PERST_FLAG:
+		devlink_flash_update_status_notify(devlink,
+						   "Activate new firmware by rebooting the system",
+						   NULL, 0, 0);
+		break;
+	case ICE_AQC_NVM_POR_FLAG:
+	default:
+		devlink_flash_update_status_notify(devlink,
+						   "Activate new firmware by power cycling the system",
+						   NULL, 0, 0);
+		break;
+	}
+
+	pf->fw_emp_reset_disabled = !priv->emp_reset_available;
+
+	return 0;
 }
 
 static const struct pldmfw_ops ice_fwu_ops = {
@@ -642,25 +745,22 @@ static const struct pldmfw_ops ice_fwu_ops = {
 };
 
 /**
- * ice_cancel_pending_update - Cancel any pending update for a component
+ * ice_get_pending_updates - Check if the component has a pending update
  * @pf: the PF driver structure
- * @component: if not NULL, the name of the component being updated
- * @extack: Netlink extended ACK structure
+ * @pending: on return, bitmap of updates pending
+ * @extack: Netlink extended ACK
  *
- * Cancel any pending update for the specified component. If component is
- * NULL, all device updates will be canceled.
+ * Check if the device has any pending updates on any flash components.
  *
- * Returns: zero on success, or a negative error code on failure.
+ * Returns: zero on success, or a negative error code on failure. Updates
+ * pending with the bitmap of pending updates.
  */
-static int
-ice_cancel_pending_update(struct ice_pf *pf, const char *component,
-			  struct netlink_ext_ack *extack)
+int ice_get_pending_updates(struct ice_pf *pf, u8 *pending,
+			    struct netlink_ext_ack *extack)
 {
-	struct devlink *devlink = priv_to_devlink(pf);
 	struct device *dev = ice_pf_to_dev(pf);
 	struct ice_hw_dev_caps *dev_caps;
 	struct ice_hw *hw = &pf->hw;
-	u8 pending = 0;
 	int err;
 
 	dev_caps = kzalloc(sizeof(*dev_caps), GFP_KERNEL);
@@ -679,23 +779,53 @@ ice_cancel_pending_update(struct ice_pf *pf, const char *component,
 		return err;
 	}
 
+	*pending = 0;
+
 	if (dev_caps->common_cap.nvm_update_pending_nvm) {
 		dev_info(dev, "The fw.mgmt flash component has a pending update\n");
-		pending |= ICE_AQC_NVM_ACTIV_SEL_NVM;
+		*pending |= ICE_AQC_NVM_ACTIV_SEL_NVM;
 	}
 
 	if (dev_caps->common_cap.nvm_update_pending_orom) {
 		dev_info(dev, "The fw.undi flash component has a pending update\n");
-		pending |= ICE_AQC_NVM_ACTIV_SEL_OROM;
+		*pending |= ICE_AQC_NVM_ACTIV_SEL_OROM;
 	}
 
 	if (dev_caps->common_cap.nvm_update_pending_netlist) {
 		dev_info(dev, "The fw.netlist flash component has a pending update\n");
-		pending |= ICE_AQC_NVM_ACTIV_SEL_NETLIST;
+		*pending |= ICE_AQC_NVM_ACTIV_SEL_NETLIST;
 	}
 
 	kfree(dev_caps);
 
+	return 0;
+}
+
+/**
+ * ice_cancel_pending_update - Cancel any pending update for a component
+ * @pf: the PF driver structure
+ * @component: if not NULL, the name of the component being updated
+ * @extack: Netlink extended ACK structure
+ *
+ * Cancel any pending update for the specified component. If component is
+ * NULL, all device updates will be canceled.
+ *
+ * Returns: zero on success, or a negative error code on failure.
+ */
+static int
+ice_cancel_pending_update(struct ice_pf *pf, const char *component,
+			  struct netlink_ext_ack *extack)
+{
+	struct devlink *devlink = priv_to_devlink(pf);
+	struct device *dev = ice_pf_to_dev(pf);
+	struct ice_hw *hw = &pf->hw;
+	u8 pending;
+	int err;
+
+	err = ice_get_pending_updates(pf, &pending, extack);
+	if (err)
+		return err;
+
 	/* If the flash_update request is for a specific component, ignore all
 	 * of the other components.
 	 */
@@ -730,10 +860,15 @@ ice_cancel_pending_update(struct ice_pf *pf, const char *component,
 	}
 
 	pending |= ICE_AQC_NVM_REVERT_LAST_ACTIV;
-	err = ice_switch_flash_banks(pf, pending, extack);
+	err = ice_switch_flash_banks(pf, pending, NULL, extack);
 
 	ice_release_nvm(hw);
 
+	/* Since we've canceled the pending update, we no longer know if EMP
+	 * reset is restricted.
+	 */
+	pf->fw_emp_reset_disabled = false;
+
 	return err;
 }