net: ena: Add a driver for Amazon Elastic Network Adapters (ENA)

This is a driver for the ENA family of networking devices.

Signed-off-by: Netanel Belgazal <netanel@annapurnalabs.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 324 insertions, 0 deletions

diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.h b/drivers/net/ethernet/amazon/ena/ena_netdev.h
new file mode 100644
index 000000000000..69d7e9ed5bc8
--- /dev/null
+++ b/drivers/net/ethernet/amazon/ena/ena_netdev.h
@@ -0,0 +1,324 @@
+/*
+ * Copyright 2015 Amazon.com, Inc. or its affiliates.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer in the documentation and/or other materials
+ *        provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#ifndef ENA_H
+#define ENA_H
+
+#include <linux/bitops.h>
+#include <linux/etherdevice.h>
+#include <linux/inetdevice.h>
+#include <linux/interrupt.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+
+#include "ena_com.h"
+#include "ena_eth_com.h"
+
+#define DRV_MODULE_VER_MAJOR	1
+#define DRV_MODULE_VER_MINOR	0
+#define DRV_MODULE_VER_SUBMINOR 2
+
+#define DRV_MODULE_NAME		"ena"
+#ifndef DRV_MODULE_VERSION
+#define DRV_MODULE_VERSION \
+	__stringify(DRV_MODULE_VER_MAJOR) "."	\
+	__stringify(DRV_MODULE_VER_MINOR) "."	\
+	__stringify(DRV_MODULE_VER_SUBMINOR)
+#endif
+
+#define DEVICE_NAME	"Elastic Network Adapter (ENA)"
+
+/* 1 for AENQ + ADMIN */
+#define ENA_MAX_MSIX_VEC(io_queues)	(1 + (io_queues))
+
+#define ENA_REG_BAR			0
+#define ENA_MEM_BAR			2
+#define ENA_BAR_MASK (BIT(ENA_REG_BAR) | BIT(ENA_MEM_BAR))
+
+#define ENA_DEFAULT_RING_SIZE	(1024)
+
+#define ENA_TX_WAKEUP_THRESH		(MAX_SKB_FRAGS + 2)
+#define ENA_DEFAULT_RX_COPYBREAK	(128 - NET_IP_ALIGN)
+
+/* limit the buffer size to 600 bytes to handle MTU changes from very
+ * small to very large, in which case the number of buffers per packet
+ * could exceed ENA_PKT_MAX_BUFS
+ */
+#define ENA_DEFAULT_MIN_RX_BUFF_ALLOC_SIZE 600
+
+#define ENA_MIN_MTU		128
+
+#define ENA_NAME_MAX_LEN	20
+#define ENA_IRQNAME_SIZE	40
+
+#define ENA_PKT_MAX_BUFS	19
+
+#define ENA_RX_RSS_TABLE_LOG_SIZE  7
+#define ENA_RX_RSS_TABLE_SIZE	(1 << ENA_RX_RSS_TABLE_LOG_SIZE)
+
+#define ENA_HASH_KEY_SIZE	40
+
+/* The number of tx packet completions that will be handled each NAPI poll
+ * cycle is ring_size / ENA_TX_POLL_BUDGET_DIVIDER.
+ */
+#define ENA_TX_POLL_BUDGET_DIVIDER	4
+
+/* Refill Rx queue when number of available descriptors is below
+ * QUEUE_SIZE / ENA_RX_REFILL_THRESH_DIVIDER
+ */
+#define ENA_RX_REFILL_THRESH_DIVIDER	8
+
+/* Number of queues to check for missing queues per timer service */
+#define ENA_MONITORED_TX_QUEUES	4
+/* Max timeout packets before device reset */
+#define MAX_NUM_OF_TIMEOUTED_PACKETS 32
+
+#define ENA_TX_RING_IDX_NEXT(idx, ring_size) (((idx) + 1) & ((ring_size) - 1))
+
+#define ENA_RX_RING_IDX_NEXT(idx, ring_size) (((idx) + 1) & ((ring_size) - 1))
+#define ENA_RX_RING_IDX_ADD(idx, n, ring_size) \
+	(((idx) + (n)) & ((ring_size) - 1))
+
+#define ENA_IO_TXQ_IDX(q)	(2 * (q))
+#define ENA_IO_RXQ_IDX(q)	(2 * (q) + 1)
+
+#define ENA_MGMNT_IRQ_IDX		0
+#define ENA_IO_IRQ_FIRST_IDX		1
+#define ENA_IO_IRQ_IDX(q)		(ENA_IO_IRQ_FIRST_IDX + (q))
+
+/* ENA device should send keep alive msg every 1 sec.
+ * We wait for 3 sec just to be on the safe side.
+ */
+#define ENA_DEVICE_KALIVE_TIMEOUT	(3 * HZ)
+
+#define ENA_MMIO_DISABLE_REG_READ	BIT(0)
+
+struct ena_irq {
+	irq_handler_t handler;
+	void *data;
+	int cpu;
+	u32 vector;
+	cpumask_t affinity_hint_mask;
+	char name[ENA_IRQNAME_SIZE];
+};
+
+struct ena_napi {
+	struct napi_struct napi ____cacheline_aligned;
+	struct ena_ring *tx_ring;
+	struct ena_ring *rx_ring;
+	u32 qid;
+};
+
+struct ena_tx_buffer {
+	struct sk_buff *skb;
+	/* num of ena desc for this specific skb
+	 * (includes data desc and metadata desc)
+	 */
+	u32 tx_descs;
+	/* num of buffers used by this skb */
+	u32 num_of_bufs;
+	/* Save the last jiffies to detect missing tx packets */
+	unsigned long last_jiffies;
+	struct ena_com_buf bufs[ENA_PKT_MAX_BUFS];
+} ____cacheline_aligned;
+
+struct ena_rx_buffer {
+	struct sk_buff *skb;
+	struct page *page;
+	u32 page_offset;
+	struct ena_com_buf ena_buf;
+} ____cacheline_aligned;
+
+struct ena_stats_tx {
+	u64 cnt;
+	u64 bytes;
+	u64 queue_stop;
+	u64 prepare_ctx_err;
+	u64 queue_wakeup;
+	u64 dma_mapping_err;
+	u64 linearize;
+	u64 linearize_failed;
+	u64 napi_comp;
+	u64 tx_poll;
+	u64 doorbells;
+	u64 missing_tx_comp;
+	u64 bad_req_id;
+};
+
+struct ena_stats_rx {
+	u64 cnt;
+	u64 bytes;
+	u64 refil_partial;
+	u64 bad_csum;
+	u64 page_alloc_fail;
+	u64 skb_alloc_fail;
+	u64 dma_mapping_err;
+	u64 bad_desc_num;
+	u64 rx_copybreak_pkt;
+};
+
+struct ena_ring {
+	/* Holds the empty requests for TX out of order completions */
+	u16 *free_tx_ids;
+	union {
+		struct ena_tx_buffer *tx_buffer_info;
+		struct ena_rx_buffer *rx_buffer_info;
+	};
+
+	/* cache ptr to avoid using the adapter */
+	struct device *dev;
+	struct pci_dev *pdev;
+	struct napi_struct *napi;
+	struct net_device *netdev;
+	struct ena_com_dev *ena_dev;
+	struct ena_adapter *adapter;
+	struct ena_com_io_cq *ena_com_io_cq;
+	struct ena_com_io_sq *ena_com_io_sq;
+
+	u16 next_to_use;
+	u16 next_to_clean;
+	u16 rx_copybreak;
+	u16 qid;
+	u16 mtu;
+	u16 sgl_size;
+
+	/* The maximum header length the device can handle */
+	u8 tx_max_header_size;
+
+	/* cpu for TPH */
+	int cpu;
+	 /* number of tx/rx_buffer_info's entries */
+	int ring_size;
+
+	enum ena_admin_placement_policy_type tx_mem_queue_type;
+
+	struct ena_com_rx_buf_info ena_bufs[ENA_PKT_MAX_BUFS];
+	u32  smoothed_interval;
+	u32  per_napi_packets;
+	u32  per_napi_bytes;
+	enum ena_intr_moder_level moder_tbl_idx;
+	struct u64_stats_sync syncp;
+	union {
+		struct ena_stats_tx tx_stats;
+		struct ena_stats_rx rx_stats;
+	};
+} ____cacheline_aligned;
+
+struct ena_stats_dev {
+	u64 tx_timeout;
+	u64 io_suspend;
+	u64 io_resume;
+	u64 wd_expired;
+	u64 interface_up;
+	u64 interface_down;
+	u64 admin_q_pause;
+};
+
+enum ena_flags_t {
+	ENA_FLAG_DEVICE_RUNNING,
+	ENA_FLAG_DEV_UP,
+	ENA_FLAG_LINK_UP,
+	ENA_FLAG_MSIX_ENABLED,
+	ENA_FLAG_TRIGGER_RESET
+};
+
+/* adapter specific private data structure */
+struct ena_adapter {
+	struct ena_com_dev *ena_dev;
+	/* OS defined structs */
+	struct net_device *netdev;
+	struct pci_dev *pdev;
+
+	/* rx packets that shorter that this len will be copied to the skb
+	 * header
+	 */
+	u32 rx_copybreak;
+	u32 max_mtu;
+
+	int num_queues;
+
+	struct msix_entry *msix_entries;
+	int msix_vecs;
+
+	u32 tx_usecs, rx_usecs; /* interrupt moderation */
+	u32 tx_frames, rx_frames; /* interrupt moderation */
+
+	u32 tx_ring_size;
+	u32 rx_ring_size;
+
+	u32 msg_enable;
+
+	u16 max_tx_sgl_size;
+	u16 max_rx_sgl_size;
+
+	u8 mac_addr[ETH_ALEN];
+
+	char name[ENA_NAME_MAX_LEN];
+
+	unsigned long flags;
+	/* TX */
+	struct ena_ring tx_ring[ENA_MAX_NUM_IO_QUEUES]
+		____cacheline_aligned_in_smp;
+
+	/* RX */
+	struct ena_ring rx_ring[ENA_MAX_NUM_IO_QUEUES]
+		____cacheline_aligned_in_smp;
+
+	struct ena_napi ena_napi[ENA_MAX_NUM_IO_QUEUES];
+
+	struct ena_irq irq_tbl[ENA_MAX_MSIX_VEC(ENA_MAX_NUM_IO_QUEUES)];
+
+	/* timer service */
+	struct work_struct reset_task;
+	struct work_struct suspend_io_task;
+	struct work_struct resume_io_task;
+	struct timer_list timer_service;
+
+	bool wd_state;
+	unsigned long last_keep_alive_jiffies;
+
+	struct u64_stats_sync syncp;
+	struct ena_stats_dev dev_stats;
+
+	/* last queue index that was checked for uncompleted tx packets */
+	u32 last_monitored_tx_qid;
+};
+
+void ena_set_ethtool_ops(struct net_device *netdev);
+
+void ena_dump_stats_to_dmesg(struct ena_adapter *adapter);
+
+void ena_dump_stats_to_buf(struct ena_adapter *adapter, u8 *buf);
+
+int ena_get_sset_count(struct net_device *netdev, int sset);
+
+#endif /* !(ENA_H) */