When enabled, firmware may send logs messages which are specific to the device and not the host. Create a ring buffer to store these messages which are read by a user through DebugFS. Buffer access is protected by a spinlock.
Signed-off-by: Lee Trager <[email protected]> Signed-off-by: Jakub Kicinski <[email protected]> --- drivers/net/ethernet/meta/fbnic/Makefile | 1 + drivers/net/ethernet/meta/fbnic/fbnic.h | 3 + .../net/ethernet/meta/fbnic/fbnic_fw_log.c | 95 +++++++++++++++++++ .../net/ethernet/meta/fbnic/fbnic_fw_log.h | 43 +++++++++ 4 files changed, 142 insertions(+) create mode 100644 drivers/net/ethernet/meta/fbnic/fbnic_fw_log.c create mode 100644 drivers/net/ethernet/meta/fbnic/fbnic_fw_log.h diff --git a/drivers/net/ethernet/meta/fbnic/Makefile b/drivers/net/ethernet/meta/fbnic/Makefile index 0dbc634adb4b..15e8ff649615 100644 --- a/drivers/net/ethernet/meta/fbnic/Makefile +++ b/drivers/net/ethernet/meta/fbnic/Makefile @@ -12,6 +12,7 @@ fbnic-y := fbnic_csr.o \ fbnic_devlink.o \ fbnic_ethtool.o \ fbnic_fw.o \ + fbnic_fw_log.o \ fbnic_hw_stats.o \ fbnic_hwmon.o \ fbnic_irq.o \ diff --git a/drivers/net/ethernet/meta/fbnic/fbnic.h b/drivers/net/ethernet/meta/fbnic/fbnic.h index 65815d4f379e..c376e06880c9 100644 --- a/drivers/net/ethernet/meta/fbnic/fbnic.h +++ b/drivers/net/ethernet/meta/fbnic/fbnic.h @@ -12,6 +12,7 @@ #include "fbnic_csr.h" #include "fbnic_fw.h" +#include "fbnic_fw_log.h" #include "fbnic_hw_stats.h" #include "fbnic_mac.h" #include "fbnic_rpc.h" @@ -85,6 +86,8 @@ struct fbnic_dev { /* Lock protecting access to hw_stats */ spinlock_t hw_stats_lock; + + struct fbnic_fw_log fw_log; }; /* Reserve entry 0 in the MSI-X "others" array until we have filled all diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_fw_log.c b/drivers/net/ethernet/meta/fbnic/fbnic_fw_log.c new file mode 100644 index 000000000000..caedbe7844f7 --- /dev/null +++ b/drivers/net/ethernet/meta/fbnic/fbnic_fw_log.c @@ -0,0 +1,95 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) Meta Platforms, Inc. and affiliates. */ + +#include <linux/spinlock.h> +#include <linux/vmalloc.h> + +#include "fbnic.h" +#include "fbnic_fw.h" +#include "fbnic_fw_log.h" + +int fbnic_fw_log_init(struct fbnic_dev *fbd) +{ + struct fbnic_fw_log *log = &fbd->fw_log; + void *data; + + if (WARN_ON_ONCE(fbnic_fw_log_ready(fbd))) + return -EEXIST; + + data = vmalloc(FBNIC_FW_LOG_SIZE); + if (!data) + return -ENOMEM; + + spin_lock_init(&fbd->fw_log.lock); + INIT_LIST_HEAD(&log->entries); + log->size = FBNIC_FW_LOG_SIZE; + log->data_start = data; + log->data_end = data + FBNIC_FW_LOG_SIZE; + + return 0; +} + +void fbnic_fw_log_free(struct fbnic_dev *fbd) +{ + struct fbnic_fw_log *log = &fbd->fw_log; + + if (!fbnic_fw_log_ready(fbd)) + return; + + INIT_LIST_HEAD(&log->entries); + log->size = 0; + vfree(log->data_start); + log->data_start = NULL; + log->data_end = NULL; +} + +int fbnic_fw_log_write(struct fbnic_dev *fbd, u64 index, u32 timestamp, + char *msg) +{ + struct fbnic_fw_log_entry *entry, *head, *tail, *next; + struct fbnic_fw_log *log = &fbd->fw_log; + size_t msg_len = strlen(msg) + 1; + unsigned long flags; + void *entry_end; + + if (!fbnic_fw_log_ready(fbd)) { + dev_err(fbd->dev, "Firmware sent log entry without being requested!\n"); + return -ENOSPC; + } + + spin_lock_irqsave(&log->lock, flags); + + if (list_empty(&log->entries)) { + entry = log->data_start; + } else { + head = list_first_entry(&log->entries, typeof(*head), list); + entry = (struct fbnic_fw_log_entry *)&head->msg[head->len + 1]; + entry = PTR_ALIGN(entry, 8); + } + + entry_end = &entry->msg[msg_len + 1]; + + /* We've reached the end of the buffer, wrap around */ + if (entry_end > log->data_end) { + entry = log->data_start; + entry_end = &entry->msg[msg_len + 1]; + } + + /* Make room for entry by removing from tail. */ + list_for_each_entry_safe_reverse(tail, next, &log->entries, list) { + if (entry <= tail && entry_end > (void *)tail) + list_del(&tail->list); + else + break; + } + + entry->index = index; + entry->timestamp = timestamp; + entry->len = msg_len; + strscpy(entry->msg, msg, entry->len); + list_add(&entry->list, &log->entries); + + spin_unlock_irqrestore(&log->lock, flags); + + return 0; +} diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_fw_log.h b/drivers/net/ethernet/meta/fbnic/fbnic_fw_log.h new file mode 100644 index 000000000000..881ee298ede7 --- /dev/null +++ b/drivers/net/ethernet/meta/fbnic/fbnic_fw_log.h @@ -0,0 +1,43 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* Copyright (c) Meta Platforms, Inc. and affiliates. */ + +#ifndef _FBNIC_FW_LOG_H_ +#define _FBNIC_FW_LOG_H_ + +#include <linux/spinlock.h> +#include <linux/types.h> + +/* A 512K log buffer was chosen fairly arbitrarily */ +#define FBNIC_FW_LOG_SIZE (512 * 1024) /* bytes */ + +/* Firmware log output is prepended with log index followed by a timestamp. + * The timestamp is similar to Zephyr's format DD:HH:MM:SS.MMM + */ +#define FBNIC_FW_LOG_FMT "[%5lld] [%02ld:%02ld:%02ld:%02ld.%03ld] %s\n" + +struct fbnic_dev; + +struct fbnic_fw_log_entry { + struct list_head list; + u64 index; + u32 timestamp; + u16 len; + char msg[] __counted_by(len); +}; + +struct fbnic_fw_log { + void *data_start; + void *data_end; + size_t size; + struct list_head entries; + /* Spin lock for accessing or modifying entries */ + spinlock_t lock; +}; + +#define fbnic_fw_log_ready(_fbd) (!!(_fbd)->fw_log.data_start) + +int fbnic_fw_log_init(struct fbnic_dev *fbd); +void fbnic_fw_log_free(struct fbnic_dev *fbd); +int fbnic_fw_log_write(struct fbnic_dev *fbd, u64 index, u32 timestamp, + char *msg); +#endif /* _FBNIC_FW_LOG_H_ */ -- 2.47.1
