xref: /linux/drivers/net/ethernet/intel/ice/ice_txrx.h (revision f86fd32d)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /* Copyright (c) 2018, Intel Corporation. */
3 
4 #ifndef _ICE_TXRX_H_
5 #define _ICE_TXRX_H_
6 
7 #include "ice_type.h"
8 
9 #define ICE_DFLT_IRQ_WORK	256
10 #define ICE_RXBUF_3072		3072
11 #define ICE_RXBUF_2048		2048
12 #define ICE_RXBUF_1536		1536
13 #define ICE_MAX_CHAINED_RX_BUFS	5
14 #define ICE_MAX_BUF_TXD		8
15 #define ICE_MIN_TX_LEN		17
16 
17 /* The size limit for a transmit buffer in a descriptor is (16K - 1).
18  * In order to align with the read requests we will align the value to
19  * the nearest 4K which represents our maximum read request size.
20  */
21 #define ICE_MAX_READ_REQ_SIZE	4096
22 #define ICE_MAX_DATA_PER_TXD	(16 * 1024 - 1)
23 #define ICE_MAX_DATA_PER_TXD_ALIGNED \
24 	(~(ICE_MAX_READ_REQ_SIZE - 1) & ICE_MAX_DATA_PER_TXD)
25 
26 #define ICE_RX_BUF_WRITE	16	/* Must be power of 2 */
27 #define ICE_MAX_TXQ_PER_TXQG	128
28 
29 /* Attempt to maximize the headroom available for incoming frames. We use a 2K
30  * buffer for MTUs <= 1500 and need 1536/1534 to store the data for the frame.
31  * This leaves us with 512 bytes of room.  From that we need to deduct the
32  * space needed for the shared info and the padding needed to IP align the
33  * frame.
34  *
35  * Note: For cache line sizes 256 or larger this value is going to end
36  *	 up negative.  In these cases we should fall back to the legacy
37  *	 receive path.
38  */
39 #if (PAGE_SIZE < 8192)
40 #define ICE_2K_TOO_SMALL_WITH_PADDING \
41 ((NET_SKB_PAD + ICE_RXBUF_1536) > SKB_WITH_OVERHEAD(ICE_RXBUF_2048))
42 
43 /**
44  * ice_compute_pad - compute the padding
45  * rx_buf_len: buffer length
46  *
47  * Figure out the size of half page based on given buffer length and
48  * then subtract the skb_shared_info followed by subtraction of the
49  * actual buffer length; this in turn results in the actual space that
50  * is left for padding usage
51  */
52 static inline int ice_compute_pad(int rx_buf_len)
53 {
54 	int half_page_size;
55 
56 	half_page_size = ALIGN(rx_buf_len, PAGE_SIZE / 2);
57 	return SKB_WITH_OVERHEAD(half_page_size) - rx_buf_len;
58 }
59 
60 /**
61  * ice_skb_pad - determine the padding that we can supply
62  *
63  * Figure out the right Rx buffer size and based on that calculate the
64  * padding
65  */
66 static inline int ice_skb_pad(void)
67 {
68 	int rx_buf_len;
69 
70 	/* If a 2K buffer cannot handle a standard Ethernet frame then
71 	 * optimize padding for a 3K buffer instead of a 1.5K buffer.
72 	 *
73 	 * For a 3K buffer we need to add enough padding to allow for
74 	 * tailroom due to NET_IP_ALIGN possibly shifting us out of
75 	 * cache-line alignment.
76 	 */
77 	if (ICE_2K_TOO_SMALL_WITH_PADDING)
78 		rx_buf_len = ICE_RXBUF_3072 + SKB_DATA_ALIGN(NET_IP_ALIGN);
79 	else
80 		rx_buf_len = ICE_RXBUF_1536;
81 
82 	/* if needed make room for NET_IP_ALIGN */
83 	rx_buf_len -= NET_IP_ALIGN;
84 
85 	return ice_compute_pad(rx_buf_len);
86 }
87 
88 #define ICE_SKB_PAD ice_skb_pad()
89 #else
90 #define ICE_2K_TOO_SMALL_WITH_PADDING false
91 #define ICE_SKB_PAD (NET_SKB_PAD + NET_IP_ALIGN)
92 #endif
93 
94 /* We are assuming that the cache line is always 64 Bytes here for ice.
95  * In order to make sure that is a correct assumption there is a check in probe
96  * to print a warning if the read from GLPCI_CNF2 tells us that the cache line
97  * size is 128 bytes. We do it this way because we do not want to read the
98  * GLPCI_CNF2 register or a variable containing the value on every pass through
99  * the Tx path.
100  */
101 #define ICE_CACHE_LINE_BYTES		64
102 #define ICE_DESCS_PER_CACHE_LINE	(ICE_CACHE_LINE_BYTES / \
103 					 sizeof(struct ice_tx_desc))
104 #define ICE_DESCS_FOR_CTX_DESC		1
105 #define ICE_DESCS_FOR_SKB_DATA_PTR	1
106 /* Tx descriptors needed, worst case */
107 #define DESC_NEEDED (MAX_SKB_FRAGS + ICE_DESCS_FOR_CTX_DESC + \
108 		     ICE_DESCS_PER_CACHE_LINE + ICE_DESCS_FOR_SKB_DATA_PTR)
109 #define ICE_DESC_UNUSED(R)	\
110 	((((R)->next_to_clean > (R)->next_to_use) ? 0 : (R)->count) + \
111 	(R)->next_to_clean - (R)->next_to_use - 1)
112 
113 #define ICE_TX_FLAGS_TSO	BIT(0)
114 #define ICE_TX_FLAGS_HW_VLAN	BIT(1)
115 #define ICE_TX_FLAGS_SW_VLAN	BIT(2)
116 #define ICE_TX_FLAGS_VLAN_M	0xffff0000
117 #define ICE_TX_FLAGS_VLAN_PR_M	0xe0000000
118 #define ICE_TX_FLAGS_VLAN_PR_S	29
119 #define ICE_TX_FLAGS_VLAN_S	16
120 
121 #define ICE_XDP_PASS		0
122 #define ICE_XDP_CONSUMED	BIT(0)
123 #define ICE_XDP_TX		BIT(1)
124 #define ICE_XDP_REDIR		BIT(2)
125 
126 #define ICE_RX_DMA_ATTR \
127 	(DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_WEAK_ORDERING)
128 
129 #define ICE_ETH_PKT_HDR_PAD	(ETH_HLEN + ETH_FCS_LEN + (VLAN_HLEN * 2))
130 
131 #define ICE_TXD_LAST_DESC_CMD (ICE_TX_DESC_CMD_EOP | ICE_TX_DESC_CMD_RS)
132 
133 struct ice_tx_buf {
134 	struct ice_tx_desc *next_to_watch;
135 	union {
136 		struct sk_buff *skb;
137 		void *raw_buf; /* used for XDP */
138 	};
139 	unsigned int bytecount;
140 	unsigned short gso_segs;
141 	u32 tx_flags;
142 	DEFINE_DMA_UNMAP_LEN(len);
143 	DEFINE_DMA_UNMAP_ADDR(dma);
144 };
145 
146 struct ice_tx_offload_params {
147 	u64 cd_qw1;
148 	struct ice_ring *tx_ring;
149 	u32 td_cmd;
150 	u32 td_offset;
151 	u32 td_l2tag1;
152 	u32 cd_tunnel_params;
153 	u16 cd_l2tag2;
154 	u8 header_len;
155 };
156 
157 struct ice_rx_buf {
158 	struct sk_buff *skb;
159 	dma_addr_t dma;
160 	union {
161 		struct {
162 			struct page *page;
163 			unsigned int page_offset;
164 			u16 pagecnt_bias;
165 		};
166 		struct {
167 			void *addr;
168 			u64 handle;
169 		};
170 	};
171 };
172 
173 struct ice_q_stats {
174 	u64 pkts;
175 	u64 bytes;
176 };
177 
178 struct ice_txq_stats {
179 	u64 restart_q;
180 	u64 tx_busy;
181 	u64 tx_linearize;
182 	int prev_pkt; /* negative if no pending Tx descriptors */
183 };
184 
185 struct ice_rxq_stats {
186 	u64 non_eop_descs;
187 	u64 alloc_page_failed;
188 	u64 alloc_buf_failed;
189 	u64 page_reuse_count;
190 };
191 
192 /* this enum matches hardware bits and is meant to be used by DYN_CTLN
193  * registers and QINT registers or more generally anywhere in the manual
194  * mentioning ITR_INDX, ITR_NONE cannot be used as an index 'n' into any
195  * register but instead is a special value meaning "don't update" ITR0/1/2.
196  */
197 enum ice_dyn_idx_t {
198 	ICE_IDX_ITR0 = 0,
199 	ICE_IDX_ITR1 = 1,
200 	ICE_IDX_ITR2 = 2,
201 	ICE_ITR_NONE = 3	/* ITR_NONE must not be used as an index */
202 };
203 
204 /* Header split modes defined by DTYPE field of Rx RLAN context */
205 enum ice_rx_dtype {
206 	ICE_RX_DTYPE_NO_SPLIT		= 0,
207 	ICE_RX_DTYPE_HEADER_SPLIT	= 1,
208 	ICE_RX_DTYPE_SPLIT_ALWAYS	= 2,
209 };
210 
211 /* indices into GLINT_ITR registers */
212 #define ICE_RX_ITR	ICE_IDX_ITR0
213 #define ICE_TX_ITR	ICE_IDX_ITR1
214 #define ICE_ITR_8K	124
215 #define ICE_ITR_20K	50
216 #define ICE_ITR_MAX	8160
217 #define ICE_DFLT_TX_ITR	(ICE_ITR_20K | ICE_ITR_DYNAMIC)
218 #define ICE_DFLT_RX_ITR	(ICE_ITR_20K | ICE_ITR_DYNAMIC)
219 #define ICE_ITR_DYNAMIC	0x8000  /* used as flag for itr_setting */
220 #define ITR_IS_DYNAMIC(setting) (!!((setting) & ICE_ITR_DYNAMIC))
221 #define ITR_TO_REG(setting)	((setting) & ~ICE_ITR_DYNAMIC)
222 #define ICE_ITR_GRAN_S		1	/* ITR granularity is always 2us */
223 #define ICE_ITR_GRAN_US		BIT(ICE_ITR_GRAN_S)
224 #define ICE_ITR_MASK		0x1FFE	/* ITR register value alignment mask */
225 #define ITR_REG_ALIGN(setting)	__ALIGN_MASK(setting, ~ICE_ITR_MASK)
226 
227 #define ICE_ITR_ADAPTIVE_MIN_INC	0x0002
228 #define ICE_ITR_ADAPTIVE_MIN_USECS	0x0002
229 #define ICE_ITR_ADAPTIVE_MAX_USECS	0x00FA
230 #define ICE_ITR_ADAPTIVE_LATENCY	0x8000
231 #define ICE_ITR_ADAPTIVE_BULK		0x0000
232 
233 #define ICE_DFLT_INTRL	0
234 #define ICE_MAX_INTRL	236
235 
236 #define ICE_WB_ON_ITR_USECS	2
237 #define ICE_IN_WB_ON_ITR_MODE	255
238 /* Sets WB_ON_ITR and assumes INTENA bit is already cleared, which allows
239  * setting the MSK_M bit to tell hardware to ignore the INTENA_M bit. Also,
240  * set the write-back latency to the usecs passed in.
241  */
242 #define ICE_GLINT_DYN_CTL_WB_ON_ITR(usecs, itr_idx)	\
243 	((((usecs) << (GLINT_DYN_CTL_INTERVAL_S - ICE_ITR_GRAN_S)) & \
244 	  GLINT_DYN_CTL_INTERVAL_M) | \
245 	 (((itr_idx) << GLINT_DYN_CTL_ITR_INDX_S) & \
246 	  GLINT_DYN_CTL_ITR_INDX_M) | GLINT_DYN_CTL_INTENA_MSK_M | \
247 	 GLINT_DYN_CTL_WB_ON_ITR_M)
248 
249 /* Legacy or Advanced Mode Queue */
250 #define ICE_TX_ADVANCED	0
251 #define ICE_TX_LEGACY	1
252 
253 /* descriptor ring, associated with a VSI */
254 struct ice_ring {
255 	/* CL1 - 1st cacheline starts here */
256 	struct ice_ring *next;		/* pointer to next ring in q_vector */
257 	void *desc;			/* Descriptor ring memory */
258 	struct device *dev;		/* Used for DMA mapping */
259 	struct net_device *netdev;	/* netdev ring maps to */
260 	struct ice_vsi *vsi;		/* Backreference to associated VSI */
261 	struct ice_q_vector *q_vector;	/* Backreference to associated vector */
262 	u8 __iomem *tail;
263 	union {
264 		struct ice_tx_buf *tx_buf;
265 		struct ice_rx_buf *rx_buf;
266 	};
267 	/* CL2 - 2nd cacheline starts here */
268 	u16 q_index;			/* Queue number of ring */
269 	u16 q_handle;			/* Queue handle per TC */
270 
271 	u8 ring_active:1;		/* is ring online or not */
272 
273 	u16 count;			/* Number of descriptors */
274 	u16 reg_idx;			/* HW register index of the ring */
275 
276 	/* used in interrupt processing */
277 	u16 next_to_use;
278 	u16 next_to_clean;
279 	u16 next_to_alloc;
280 
281 	/* stats structs */
282 	struct ice_q_stats	stats;
283 	struct u64_stats_sync syncp;
284 	union {
285 		struct ice_txq_stats tx_stats;
286 		struct ice_rxq_stats rx_stats;
287 	};
288 
289 	struct rcu_head rcu;		/* to avoid race on free */
290 	struct bpf_prog *xdp_prog;
291 	struct xdp_umem *xsk_umem;
292 	struct zero_copy_allocator zca;
293 	/* CL3 - 3rd cacheline starts here */
294 	struct xdp_rxq_info xdp_rxq;
295 	/* CLX - the below items are only accessed infrequently and should be
296 	 * in their own cache line if possible
297 	 */
298 #define ICE_TX_FLAGS_RING_XDP		BIT(0)
299 #define ICE_RX_FLAGS_RING_BUILD_SKB	BIT(1)
300 	u8 flags;
301 	dma_addr_t dma;			/* physical address of ring */
302 	unsigned int size;		/* length of descriptor ring in bytes */
303 	u32 txq_teid;			/* Added Tx queue TEID */
304 	u16 rx_buf_len;
305 	u8 dcb_tc;			/* Traffic class of ring */
306 } ____cacheline_internodealigned_in_smp;
307 
308 static inline bool ice_ring_uses_build_skb(struct ice_ring *ring)
309 {
310 	return !!(ring->flags & ICE_RX_FLAGS_RING_BUILD_SKB);
311 }
312 
313 static inline void ice_set_ring_build_skb_ena(struct ice_ring *ring)
314 {
315 	ring->flags |= ICE_RX_FLAGS_RING_BUILD_SKB;
316 }
317 
318 static inline void ice_clear_ring_build_skb_ena(struct ice_ring *ring)
319 {
320 	ring->flags &= ~ICE_RX_FLAGS_RING_BUILD_SKB;
321 }
322 
323 static inline bool ice_ring_is_xdp(struct ice_ring *ring)
324 {
325 	return !!(ring->flags & ICE_TX_FLAGS_RING_XDP);
326 }
327 
328 struct ice_ring_container {
329 	/* head of linked-list of rings */
330 	struct ice_ring *ring;
331 	unsigned long next_update;	/* jiffies value of next queue update */
332 	unsigned int total_bytes;	/* total bytes processed this int */
333 	unsigned int total_pkts;	/* total packets processed this int */
334 	u16 itr_idx;		/* index in the interrupt vector */
335 	u16 target_itr;		/* value in usecs divided by the hw->itr_gran */
336 	u16 current_itr;	/* value in usecs divided by the hw->itr_gran */
337 	/* high bit set means dynamic ITR, rest is used to store user
338 	 * readable ITR value in usecs and must be converted before programming
339 	 * to a register.
340 	 */
341 	u16 itr_setting;
342 };
343 
344 struct ice_coalesce_stored {
345 	u16 itr_tx;
346 	u16 itr_rx;
347 	u8 intrl;
348 };
349 
350 /* iterator for handling rings in ring container */
351 #define ice_for_each_ring(pos, head) \
352 	for (pos = (head).ring; pos; pos = pos->next)
353 
354 static inline unsigned int ice_rx_pg_order(struct ice_ring *ring)
355 {
356 #if (PAGE_SIZE < 8192)
357 	if (ring->rx_buf_len > (PAGE_SIZE / 2))
358 		return 1;
359 #endif
360 	return 0;
361 }
362 
363 #define ice_rx_pg_size(_ring) (PAGE_SIZE << ice_rx_pg_order(_ring))
364 
365 union ice_32b_rx_flex_desc;
366 
367 bool ice_alloc_rx_bufs(struct ice_ring *rxr, u16 cleaned_count);
368 netdev_tx_t ice_start_xmit(struct sk_buff *skb, struct net_device *netdev);
369 void ice_clean_tx_ring(struct ice_ring *tx_ring);
370 void ice_clean_rx_ring(struct ice_ring *rx_ring);
371 int ice_setup_tx_ring(struct ice_ring *tx_ring);
372 int ice_setup_rx_ring(struct ice_ring *rx_ring);
373 void ice_free_tx_ring(struct ice_ring *tx_ring);
374 void ice_free_rx_ring(struct ice_ring *rx_ring);
375 int ice_napi_poll(struct napi_struct *napi, int budget);
376 
377 #endif /* _ICE_TXRX_H_ */
378