Tue, Jun 30, 2020 at 01:34:06PM CEST, vasundhara-v.vo...@broadcom.com wrote: >Advanced NICs support live reset of some of the hardware >components, that resets the device immediately with all the >host drivers loaded. > >Add devlink reset subcommand to support live and deferred modes >of reset. It allows to reset the hardware components of the >entire device and supports the following fields: > >component: >---------- >1. MGMT : Management processor. >2. DMA : DMA engine. >3. RAM : RAM shared between multiple components. >4. AP : Application processor. >5. ROCE : RoCE management processor. >6. All : All possible components. > >Drivers are allowed to reset only a subset of requested components.
I don't understand why would user ever want to do this. He does not care about some magic hw entities. He just expects the hw to work. I don't undestand the purpose of exposing something like this. Could you please explain in details? Thanks! > >width: >------ >1. single - single host. >2. multi - Multi host. > >mode: >----- >1. deferred - Reset will happen after unloading all the host drivers > on the device. This is be default reset type, if user > does not specify the type. >2. live - Reset will happen immediately with all host drivers loaded > in real time. If the live reset is not supported, driver > will return the error. > >This patch is a proposal in continuation to discussion to the >following thread: > >"[PATCH v3 net-next 0/6] bnxt_en: Add 'enable_live_dev_reset' and >'allow_live_dev_reset' generic devlink params." > >and here is the URL to the patch series: > >https://patchwork.ozlabs.org/project/netdev/list/?series=180426&state=* > >If the proposal looks good, I will re-send the whole patchset >including devlink changes and driver usage. > >Signed-off-by: Vasundhara Volam <vasundhara-v.vo...@broadcom.com> >Reviewed-by: Michael Chan <michael.c...@broadcom.com> >--- >v2: >- Switch RAM and AP component definitions. >- Remove IRQ, FILTER, OFFLOAD, MAC, PHY components as they are port >specific components. >- Rename function to host in width parameter. >--- > Documentation/networking/devlink/devlink-reset.rst | 50 +++++++++++++ > include/net/devlink.h | 2 + > include/uapi/linux/devlink.h | 46 ++++++++++++ > net/core/devlink.c | 85 ++++++++++++++++++++++ > 4 files changed, 183 insertions(+) > create mode 100644 Documentation/networking/devlink/devlink-reset.rst > >diff --git a/Documentation/networking/devlink/devlink-reset.rst >b/Documentation/networking/devlink/devlink-reset.rst >new file mode 100644 >index 0000000..652800d >--- /dev/null >+++ b/Documentation/networking/devlink/devlink-reset.rst >@@ -0,0 +1,50 @@ >+.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) >+ >+.. _devlink_reset: >+ >+============= >+Devlink reset >+============= >+ >+The ``devlink-reset`` API allows reset the hardware components of the device. >After the reset, >+device loads the pending updated firmware image. >+Example use:: >+ >+ $ devlink dev reset pci/0000:05:00.0 components COMPONENTS >+ >+Note that user can mention multiple components. >+ >+================ >+Reset components >+================ >+ >+List of available components:: >+ >+``DEVLINK_RESET_COMP_MGMT`` - Management processor. >+``DEVLINK_RESET_COMP_DMA`` - DMA engine. >+``DEVLINK_RESET_COMP_RAM`` - RAM shared between multiple components. >+``DEVLINK_RESET_COMP_AP`` - Application processor. >+``DEVLINK_RESET_COMP_ROCE`` - RoCE management processor. >+``DEVLINK_RESET_COMP_ALL`` - All components. >+ >+=========== >+Reset width >+=========== >+ >+List of available widths:: >+ >+``DEVLINK_RESET_WIDTH_SINGLE`` - Device is used by single dedicated host. >+``DEVLINK_RESET_WIDTH_MULTI`` - Device is shared across multiple hosts. >+ >+Note that if user specifies DEVLINK_RESET_WIDTH_SINGLE in a multi-host >environment, driver returns >+error if it does not support resetting a single host. >+ >+=========== >+Reset modes >+=========== >+ >+List of available reset modes:: >+ >+``DEVLINK_RESET_MODE_DEFERRED`` - Reset happens after all host drivers are >unloaded on the device. >+``DEVLINK_RESET_MODE_LIVE`` - Reset happens immediately, with all loaded >host drivers in real >+ time. >diff --git a/include/net/devlink.h b/include/net/devlink.h >index 428f55f..a71c8f5 100644 >--- a/include/net/devlink.h >+++ b/include/net/devlink.h >@@ -1129,6 +1129,8 @@ struct devlink_ops { > int (*port_function_hw_addr_set)(struct devlink *devlink, struct > devlink_port *port, > const u8 *hw_addr, int hw_addr_len, > struct netlink_ext_ack *extack); >+ int (*reset)(struct devlink *devlink, u32 *components, u8 width, u8 >mode, >+ struct netlink_ext_ack *extack); > }; > > static inline void *devlink_priv(struct devlink *devlink) >diff --git a/include/uapi/linux/devlink.h b/include/uapi/linux/devlink.h >index 87c83a8..6f32c00 100644 >--- a/include/uapi/linux/devlink.h >+++ b/include/uapi/linux/devlink.h >@@ -122,6 +122,9 @@ enum devlink_command { > DEVLINK_CMD_TRAP_POLICER_NEW, > DEVLINK_CMD_TRAP_POLICER_DEL, > >+ DEVLINK_CMD_RESET, >+ DEVLINK_CMD_RESET_STATUS, /* notification only */ >+ > /* add new commands above here */ > __DEVLINK_CMD_MAX, > DEVLINK_CMD_MAX = __DEVLINK_CMD_MAX - 1 >@@ -265,6 +268,44 @@ enum devlink_trap_type { > DEVLINK_TRAP_TYPE_CONTROL, > }; > >+/** >+ * enum devlink_reset_component - Reset components. >+ * @DEVLINK_RESET_COMP_MGMT: Management processor. >+ * @DEVLINK_RESET_COMP_DMA: DMA engine. >+ * @DEVLINK_RESET_COMP_RAM: RAM shared between multiple components. >+ * @DEVLINK_RESET_COMP_AP: Application processor. >+ * @DEVLINK_RESET_COMP_ROCE: RoCE management processor. >+ * @DEVLINK_RESET_COMP_ALL: All components. >+ */ >+enum devlink_reset_component { >+ DEVLINK_RESET_COMP_MGMT = (1 << 0), >+ DEVLINK_RESET_COMP_DMA = (1 << 1), >+ DEVLINK_RESET_COMP_RAM = (1 << 2), >+ DEVLINK_RESET_COMP_AP = (1 << 3), >+ DEVLINK_RESET_COMP_ROCE = (1 << 4), >+ DEVLINK_RESET_COMP_ALL = 0xffffffff, >+}; >+ >+/** >+ * enum devlink_reset_width - Number of hosts effected by reset. >+ * @DEVLINK_RESET_WIDTH_SINGLE: Device is used by single dedicated host. >+ * @DEVLINK_RESET_WIDTH_MULTI: Device is shared across multiple hosts. >+ */ >+enum devlink_reset_width { >+ DEVLINK_RESET_WIDTH_SINGLE = 0, >+ DEVLINK_RESET_WIDTH_MULTI = 1, >+}; >+ >+/** >+ * enum devlink_reset_mode - Modes of reset. >+ * @DEVLINK_RESET_MODE_DEFERRED: Reset will happen after host drivers are >unloaded. >+ * @DEVLINK_RESET_MODE_LIVE: All host drivers also will be reset without >reloading manually. >+ */ >+enum devlink_reset_mode { >+ DEVLINK_RESET_MODE_DEFERRED = 0, >+ DEVLINK_RESET_MODE_LIVE = 1, >+}; >+ > enum { > /* Trap can report input port as metadata */ > DEVLINK_ATTR_TRAP_METADATA_TYPE_IN_PORT, >@@ -455,6 +496,11 @@ enum devlink_attr { > > DEVLINK_ATTR_INFO_BOARD_SERIAL_NUMBER, /* string */ > >+ DEVLINK_ATTR_RESET_COMPONENTS, /* u32 */ >+ DEVLINK_ATTR_RESET_WIDTH, /* u8 */ >+ DEVLINK_ATTR_RESET_MODE, /* u8 */ >+ DEVLINK_ATTR_RESET_STATUS_MSG, /* string */ >+ > /* add new attributes above here, update the policy in devlink.c */ > > __DEVLINK_ATTR_MAX, >diff --git a/net/core/devlink.c b/net/core/devlink.c >index 6ae3680..c0eebc5 100644 >--- a/net/core/devlink.c >+++ b/net/core/devlink.c >@@ -6797,6 +6797,82 @@ static int devlink_nl_cmd_trap_policer_set_doit(struct >sk_buff *skb, > return devlink_trap_policer_set(devlink, policer_item, info); > } > >+static int devlink_nl_reset_fill(struct sk_buff *msg, struct devlink *devlink, >+ const char *status_msg, u32 components) >+{ >+ void *hdr; >+ >+ hdr = genlmsg_put(msg, 0, 0, &devlink_nl_family, 0, >DEVLINK_CMD_RESET_STATUS); >+ if (!hdr) >+ return -EMSGSIZE; >+ >+ if (devlink_nl_put_handle(msg, devlink)) >+ goto nla_put_failure; >+ >+ if (status_msg && nla_put_string(msg, DEVLINK_ATTR_RESET_STATUS_MSG, >status_msg)) >+ goto nla_put_failure; >+ >+ if (nla_put_u32(msg, DEVLINK_ATTR_RESET_COMPONENTS, components)) >+ goto nla_put_failure; >+ >+ genlmsg_end(msg, hdr); >+ return 0; >+ >+nla_put_failure: >+ genlmsg_cancel(msg, hdr); >+ return -EMSGSIZE; >+} >+ >+static void __devlink_reset_notify(struct devlink *devlink, const char >*status_msg, u32 components) >+{ >+ struct sk_buff *msg; >+ int err; >+ >+ msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); >+ if (!msg) >+ return; >+ >+ err = devlink_nl_reset_fill(msg, devlink, status_msg, components); >+ if (err) >+ goto out; >+ >+ genlmsg_multicast_netns(&devlink_nl_family, devlink_net(devlink), msg, >0, >+ DEVLINK_MCGRP_CONFIG, GFP_KERNEL); >+ return; >+ >+out: >+ nlmsg_free(msg); >+} >+ >+static int devlink_nl_cmd_reset(struct sk_buff *skb, struct genl_info *info) >+{ >+ struct devlink *devlink = info->user_ptr[0]; >+ u32 components, req_comps; >+ struct nlattr *nla_type; >+ u8 width, mode; >+ int err; >+ >+ if (!devlink->ops->reset) >+ return -EOPNOTSUPP; >+ >+ if (!info->attrs[DEVLINK_ATTR_RESET_COMPONENTS]) >+ return -EINVAL; >+ components = nla_get_u32(info->attrs[DEVLINK_ATTR_RESET_COMPONENTS]); >+ >+ nla_type = info->attrs[DEVLINK_ATTR_RESET_WIDTH]; >+ width = nla_type ? nla_get_u8(nla_type) : DEVLINK_RESET_WIDTH_SINGLE; >+ >+ nla_type = info->attrs[DEVLINK_ATTR_RESET_MODE]; >+ mode = nla_type ? nla_get_u8(nla_type) : DEVLINK_RESET_MODE_DEFERRED; >+ >+ req_comps = components; >+ __devlink_reset_notify(devlink, "Reset request", components); >+ err = devlink->ops->reset(devlink, &components, width, mode, >info->extack); >+ __devlink_reset_notify(devlink, "Components reset", req_comps & >~components); >+ >+ return err; >+} >+ > static const struct nla_policy devlink_nl_policy[DEVLINK_ATTR_MAX + 1] = { > [DEVLINK_ATTR_UNSPEC] = { .strict_start_type = > DEVLINK_ATTR_TRAP_POLICER_ID }, >@@ -6842,6 +6918,9 @@ static int devlink_nl_cmd_trap_policer_set_doit(struct >sk_buff *skb, > [DEVLINK_ATTR_TRAP_POLICER_RATE] = { .type = NLA_U64 }, > [DEVLINK_ATTR_TRAP_POLICER_BURST] = { .type = NLA_U64 }, > [DEVLINK_ATTR_PORT_FUNCTION] = { .type = NLA_NESTED }, >+ [DEVLINK_ATTR_RESET_COMPONENTS] = { .type = NLA_U32 }, >+ [DEVLINK_ATTR_RESET_WIDTH] = { .type = NLA_U8 }, >+ [DEVLINK_ATTR_RESET_MODE] = { .type = NLA_U8 }, > }; > > static const struct genl_ops devlink_nl_ops[] = { >@@ -7190,6 +7269,12 @@ static int devlink_nl_cmd_trap_policer_set_doit(struct >sk_buff *skb, > .flags = GENL_ADMIN_PERM, > .internal_flags = DEVLINK_NL_FLAG_NEED_DEVLINK, > }, >+ { >+ .cmd = DEVLINK_CMD_RESET, >+ .doit = devlink_nl_cmd_reset, >+ .flags = GENL_ADMIN_PERM, >+ .internal_flags = DEVLINK_NL_FLAG_NEED_DEVLINK, >+ }, > }; > > static struct genl_family devlink_nl_family __ro_after_init = { >-- >1.8.3.1 >
