xref: /linux/drivers/net/ethernet/google/gve/gve_dqo.h (revision e7d759f31ca295d589f7420719c311870bb3166f)
1 /* SPDX-License-Identifier: (GPL-2.0 OR MIT)
2  * Google virtual Ethernet (gve) driver
3  *
4  * Copyright (C) 2015-2021 Google, Inc.
5  */
6 
7 #ifndef _GVE_DQO_H_
8 #define _GVE_DQO_H_
9 
10 #include "gve_adminq.h"
11 
12 #define GVE_ITR_ENABLE_BIT_DQO BIT(0)
13 #define GVE_ITR_CLEAR_PBA_BIT_DQO BIT(1)
14 #define GVE_ITR_NO_UPDATE_DQO (3 << 3)
15 
16 #define GVE_ITR_INTERVAL_DQO_SHIFT 5
17 #define GVE_ITR_INTERVAL_DQO_MASK ((1 << 12) - 1)
18 
19 #define GVE_TX_IRQ_RATELIMIT_US_DQO 50
20 #define GVE_RX_IRQ_RATELIMIT_US_DQO 20
21 #define GVE_MAX_ITR_INTERVAL_DQO (GVE_ITR_INTERVAL_DQO_MASK * 2)
22 
23 /* Timeout in seconds to wait for a reinjection completion after receiving
24  * its corresponding miss completion.
25  */
26 #define GVE_REINJECT_COMPL_TIMEOUT 1
27 
28 /* Timeout in seconds to deallocate the completion tag for a packet that was
29  * prematurely freed for not receiving a valid completion. This should be large
30  * enough to rule out the possibility of receiving the corresponding valid
31  * completion after this interval.
32  */
33 #define GVE_DEALLOCATE_COMPL_TIMEOUT 60
34 
35 netdev_tx_t gve_tx_dqo(struct sk_buff *skb, struct net_device *dev);
36 netdev_features_t gve_features_check_dqo(struct sk_buff *skb,
37 					 struct net_device *dev,
38 					 netdev_features_t features);
39 bool gve_tx_poll_dqo(struct gve_notify_block *block, bool do_clean);
40 int gve_rx_poll_dqo(struct gve_notify_block *block, int budget);
41 int gve_tx_alloc_rings_dqo(struct gve_priv *priv);
42 void gve_tx_free_rings_dqo(struct gve_priv *priv);
43 int gve_rx_alloc_rings_dqo(struct gve_priv *priv);
44 void gve_rx_free_rings_dqo(struct gve_priv *priv);
45 int gve_clean_tx_done_dqo(struct gve_priv *priv, struct gve_tx_ring *tx,
46 			  struct napi_struct *napi);
47 void gve_rx_post_buffers_dqo(struct gve_rx_ring *rx);
48 void gve_rx_write_doorbell_dqo(const struct gve_priv *priv, int queue_idx);
49 
50 static inline void
51 gve_tx_put_doorbell_dqo(const struct gve_priv *priv,
52 			const struct gve_queue_resources *q_resources, u32 val)
53 {
54 	u64 index;
55 
56 	index = be32_to_cpu(q_resources->db_index);
57 	iowrite32(val, &priv->db_bar2[index]);
58 }
59 
60 /* Builds register value to write to DQO IRQ doorbell to enable with specified
61  * ITR interval.
62  */
63 static inline u32 gve_setup_itr_interval_dqo(u32 interval_us)
64 {
65 	u32 result = GVE_ITR_ENABLE_BIT_DQO;
66 
67 	/* Interval has 2us granularity. */
68 	interval_us >>= 1;
69 
70 	interval_us &= GVE_ITR_INTERVAL_DQO_MASK;
71 	result |= (interval_us << GVE_ITR_INTERVAL_DQO_SHIFT);
72 
73 	return result;
74 }
75 
76 static inline void
77 gve_write_irq_doorbell_dqo(const struct gve_priv *priv,
78 			   const struct gve_notify_block *block, u32 val)
79 {
80 	u32 index = be32_to_cpu(*block->irq_db_index);
81 
82 	iowrite32(val, &priv->db_bar2[index]);
83 }
84 
85 /* Sets interrupt throttling interval and enables interrupt
86  * by writing to IRQ doorbell.
87  */
88 static inline void
89 gve_set_itr_coalesce_usecs_dqo(struct gve_priv *priv,
90 			       struct gve_notify_block *block,
91 			       u32 usecs)
92 {
93 	gve_write_irq_doorbell_dqo(priv, block,
94 				   gve_setup_itr_interval_dqo(usecs));
95 }
96 #endif /* _GVE_DQO_H_ */
97