[PATCH net-next v3 09/10] ethtool: Add ability to flash transceiver modules' firmware

[Danielle Ratson <danieller@nvidia.com>]

Add the ability to flash the modules' firmware by implementing the
interface between the user space and the kernel.

Example from a succeeding implementation:

 # ethtool --flash-module-firmware swp40 file test.bin

 Transceiver module firmware flashing started for device eth0

 Transceiver module firmware flashing in progress for device eth0
 Status message: Downloading firmware image
 Progress: 0%

 [...]

 Transceiver module firmware flashing in progress for device eth0
 Status message: Downloading firmware image
 Progress: 50%

 [...]

 Transceiver module firmware flashing in progress for device eth0
 Status message: Downloading firmware image
 Progress: 100%

 Transceiver module firmware flashing completed for device eth0

Signed-off-by: Danielle Ratson <danieller@nvidia.com>
---
 net/ethtool/module.c  | 174 ++++++++++++++++++++++++++++++++++++++++++
 net/ethtool/netlink.c |   7 ++
 net/ethtool/netlink.h |   2 +
 3 files changed, 183 insertions(+)

diff --git a/net/ethtool/module.c b/net/ethtool/module.c
index 1c659bd85160..836c198d2cc4 100644
--- a/net/ethtool/module.c
+++ b/net/ethtool/module.c
@@ -1,6 +1,8 @@
 // SPDX-License-Identifier: GPL-2.0-only
 
 #include <linux/ethtool.h>
+#include <linux/firmware.h>
+#include <linux/sfp.h>
 
 #include "netlink.h"
 #include "common.h"
@@ -160,6 +162,178 @@ const struct ethnl_request_ops ethnl_module_request_ops = {
 	.set_ntf_cmd		= ETHTOOL_MSG_MODULE_NTF,
 };
 
+/* MODULE_FW_FLASH_ACT */
+
+const struct nla_policy
+ethnl_module_fw_flash_act_policy[ETHTOOL_A_MODULE_FW_FLASH_PASSWORD + 1] = {
+	[ETHTOOL_A_MODULE_FW_FLASH_HEADER] =
+		NLA_POLICY_NESTED(ethnl_header_policy),
+	[ETHTOOL_A_MODULE_FW_FLASH_FILE_NAME] = { .type = NLA_NUL_STRING },
+	[ETHTOOL_A_MODULE_FW_FLASH_PASSWORD] = { .type = NLA_U32 },
+};
+
+#define MODULE_EEPROM_PHYS_ID_PAGE	0
+#define MODULE_EEPROM_PHYS_ID_I2C_ADDR	0x50
+
+static int module_flash_fw_work_init(struct ethtool_module_fw_flash *module_fw,
+				     struct net_device *dev,
+				     struct netlink_ext_ack *extack)
+{
+	const struct ethtool_ops *ops = dev->ethtool_ops;
+	struct ethtool_module_eeprom page_data = {};
+	u8 phys_id;
+	int err;
+
+	/* Fetch the SFF-8024 Identifier Value. For all supported standards, it
+	 * is located at I2C address 0x50, byte 0. See section 4.1 in SFF-8024,
+	 * revision 4.9.
+	 */
+	page_data.page = MODULE_EEPROM_PHYS_ID_PAGE;
+	page_data.offset = SFP_PHYS_ID;
+	page_data.length = sizeof(phys_id);
+	page_data.i2c_address = MODULE_EEPROM_PHYS_ID_I2C_ADDR;
+	page_data.data = &phys_id;
+
+	err = ops->get_module_eeprom_by_page(dev, &page_data, extack);
+	if (err < 0)
+		return err;
+
+	switch (phys_id) {
+	case SFF8024_ID_QSFP_DD:
+	case SFF8024_ID_OSFP:
+	case SFF8024_ID_DSFP:
+	case SFF8024_ID_QSFP_PLUS_CMIS:
+	case SFF8024_ID_SFP_DD_CMIS:
+	case SFF8024_ID_SFP_PLUS_CMIS:
+		INIT_WORK(&module_fw->work, ethtool_cmis_fw_update);
+		break;
+	default:
+		NL_SET_ERR_MSG(extack,
+			       "Module type does not support firmware flashing");
+		return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
+
+static int __module_flash_fw_schedule(struct net_device *dev,
+				      struct netlink_ext_ack *extack)
+{
+	const struct ethtool_ops *ops = dev->ethtool_ops;
+
+	if (!ops->set_module_eeprom_by_page ||
+	    !ops->get_module_eeprom_by_page) {
+		NL_SET_ERR_MSG(extack,
+			       "Flashing module firmware is not supported by this device");
+		return -EOPNOTSUPP;
+	}
+
+	if (!ops->reset) {
+		NL_SET_ERR_MSG(extack,
+			       "Reset module is not supported by this device, so flashing is not permitted");
+		return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
+
+static int
+module_flash_fw_schedule(struct net_device *dev, const char *file_name,
+			 struct ethtool_module_fw_flash_params *params,
+			 struct netlink_ext_ack *extack)
+{
+	struct ethtool_module_fw_flash *module_fw;
+	int err;
+
+	err = __module_flash_fw_schedule(dev, extack);
+	if (err < 0)
+		return err;
+
+	module_fw = kzalloc(sizeof(*module_fw), GFP_KERNEL);
+	if (!module_fw)
+		return -ENOMEM;
+
+	module_fw->params = *params;
+	err = request_firmware_direct(&module_fw->fw, file_name, &dev->dev);
+	if (err) {
+		NL_SET_ERR_MSG(extack,
+			       "Failed to request module firmware image");
+		goto err_request_firmware;
+	}
+
+	err = module_flash_fw_work_init(module_fw, dev, extack);
+	if (err < 0) {
+		NL_SET_ERR_MSG(extack,
+			       "Flashing module firmware is not supported by this device");
+		goto err_work_init;
+	}
+
+	dev->module_fw_flash_in_progress = true;
+	netdev_hold(dev, &module_fw->dev_tracker, GFP_KERNEL);
+	module_fw->dev = dev;
+
+	schedule_work(&module_fw->work);
+
+	return 0;
+
+err_work_init:
+	release_firmware(module_fw->fw);
+err_request_firmware:
+	kfree(module_fw);
+	return err;
+}
+
+static int module_flash_fw(struct net_device *dev, struct nlattr **tb,
+			   struct genl_info *info)
+{
+	struct ethtool_module_fw_flash_params params = {};
+	const char *file_name;
+	struct nlattr *attr;
+
+	if (GENL_REQ_ATTR_CHECK(info, ETHTOOL_A_MODULE_FW_FLASH_FILE_NAME))
+		return -EINVAL;
+
+	file_name = nla_data(tb[ETHTOOL_A_MODULE_FW_FLASH_FILE_NAME]);
+
+	attr = tb[ETHTOOL_A_MODULE_FW_FLASH_PASSWORD];
+	if (attr) {
+		params.password = cpu_to_be32(nla_get_u32(attr));
+		params.password_valid = true;
+	}
+
+	return module_flash_fw_schedule(dev, file_name, &params, info->extack);
+}
+
+int ethnl_act_module_fw_flash(struct sk_buff *skb, struct genl_info *info)
+{
+	struct ethnl_req_info req_info = {};
+	struct nlattr **tb = info->attrs;
+	struct net_device *dev;
+	int ret;
+
+	ret = ethnl_parse_header_dev_get(&req_info,
+					 tb[ETHTOOL_A_MODULE_FW_FLASH_HEADER],
+					 genl_info_net(info), info->extack,
+					 true);
+	if (ret < 0)
+		return ret;
+	dev = req_info.dev;
+
+	rtnl_lock();
+	ret = ethnl_ops_begin(dev);
+	if (ret < 0)
+		goto out_rtnl;
+
+	ret = module_flash_fw(dev, tb, info);
+
+	ethnl_ops_complete(dev);
+
+out_rtnl:
+	rtnl_unlock();
+	ethnl_parse_header_dev_put(&req_info);
+	return ret;
+}
+
 /* MODULE_FW_FLASH_NTF */
 
 static void
diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c
index 563e94e0cbd8..1a4f6bd1ec7f 100644
--- a/net/ethtool/netlink.c
+++ b/net/ethtool/netlink.c
@@ -1169,6 +1169,13 @@ static const struct genl_ops ethtool_genl_ops[] = {
 		.policy = ethnl_mm_set_policy,
 		.maxattr = ARRAY_SIZE(ethnl_mm_set_policy) - 1,
 	},
+	{
+		.cmd	= ETHTOOL_MSG_MODULE_FW_FLASH_ACT,
+		.flags	= GENL_UNS_ADMIN_PERM,
+		.doit	= ethnl_act_module_fw_flash,
+		.policy	= ethnl_module_fw_flash_act_policy,
+		.maxattr = ARRAY_SIZE(ethnl_module_fw_flash_act_policy) - 1,
+	},
 };
 
 static const struct genl_multicast_group ethtool_nl_mcgrps[] = {
diff --git a/net/ethtool/netlink.h b/net/ethtool/netlink.h
index d57a890b5d9e..e1e2edd05206 100644
--- a/net/ethtool/netlink.h
+++ b/net/ethtool/netlink.h
@@ -446,6 +446,7 @@ extern const struct nla_policy ethnl_plca_set_cfg_policy[ETHTOOL_A_PLCA_MAX + 1]
 extern const struct nla_policy ethnl_plca_get_status_policy[ETHTOOL_A_PLCA_HEADER + 1];
 extern const struct nla_policy ethnl_mm_get_policy[ETHTOOL_A_MM_HEADER + 1];
 extern const struct nla_policy ethnl_mm_set_policy[ETHTOOL_A_MM_MAX + 1];
+extern const struct nla_policy ethnl_module_fw_flash_act_policy[ETHTOOL_A_MODULE_FW_FLASH_PASSWORD + 1];
 
 int ethnl_set_features(struct sk_buff *skb, struct genl_info *info);
 int ethnl_act_cable_test(struct sk_buff *skb, struct genl_info *info);
@@ -453,6 +454,7 @@ int ethnl_act_cable_test_tdr(struct sk_buff *skb, struct genl_info *info);
 int ethnl_tunnel_info_doit(struct sk_buff *skb, struct genl_info *info);
 int ethnl_tunnel_info_start(struct netlink_callback *cb);
 int ethnl_tunnel_info_dumpit(struct sk_buff *skb, struct netlink_callback *cb);
+int ethnl_act_module_fw_flash(struct sk_buff *skb, struct genl_info *info);
 
 extern const char stats_std_names[__ETHTOOL_STATS_CNT][ETH_GSTRING_LEN];
 extern const char stats_eth_phy_names[__ETHTOOL_A_STATS_ETH_PHY_CNT][ETH_GSTRING_LEN];
-- 
2.43.0