1// SPDX-License-Identifier: GPL-2.0
2/* Marvell Octeon EP (EndPoint) Ethernet Driver
3 *
4 * Copyright (C) 2020 Marvell.
5 *
6 */
7
8#include <linux/pci.h>
9#include <linux/etherdevice.h>
10#include <linux/vmalloc.h>
11
12#include "octep_config.h"
13#include "octep_main.h"
14
15/* Reset various index of Tx queue data structure. */
16static void octep_iq_reset_indices(struct octep_iq *iq)
17{
18 iq->fill_cnt = 0;
19 iq->host_write_index = 0;
20 iq->octep_read_index = 0;
21 iq->flush_index = 0;
22 iq->pkts_processed = 0;
23 iq->pkt_in_done = 0;
24}
25
26/**
27 * octep_iq_process_completions() - Process Tx queue completions.
28 *
29 * @iq: Octeon Tx queue data structure.
30 * @budget: max number of completions to be processed in one invocation.
31 */
32int octep_iq_process_completions(struct octep_iq *iq, u16 budget)
33{
34 u32 compl_pkts, compl_bytes, compl_sg;
35 struct octep_device *oct = iq->octep_dev;
36 struct octep_tx_buffer *tx_buffer;
37 struct skb_shared_info *shinfo;
38 u32 fi = iq->flush_index;
39 struct sk_buff *skb;
40 u8 frags, i;
41
42 compl_pkts = 0;
43 compl_sg = 0;
44 compl_bytes = 0;
45 iq->octep_read_index = oct->hw_ops.update_iq_read_idx(iq);
46
47 while (likely(budget && (fi != iq->octep_read_index))) {
48 tx_buffer = iq->buff_info + fi;
49 skb = tx_buffer->skb;
50
51 fi++;
52 if (unlikely(fi == iq->max_count))
53 fi = 0;
54 compl_bytes += skb->len;
55 compl_pkts++;
56 budget--;
57
58 if (!tx_buffer->gather) {
59 dma_unmap_single(iq->dev, tx_buffer->dma,
60 tx_buffer->skb->len, DMA_TO_DEVICE);
61 dev_kfree_skb_any(skb);
62 continue;
63 }
64
65 /* Scatter/Gather */
66 shinfo = skb_shinfo(skb);
67 frags = shinfo->nr_frags;
68 compl_sg++;
69
70 dma_unmap_single(iq->dev, tx_buffer->sglist[0].dma_ptr[0],
71 tx_buffer->sglist[0].len[3], DMA_TO_DEVICE);
72
73 i = 1; /* entry 0 is main skb, unmapped above */
74 while (frags--) {
75 dma_unmap_page(iq->dev, tx_buffer->sglist[i >> 2].dma_ptr[i & 3],
76 tx_buffer->sglist[i >> 2].len[3 - (i & 3)], DMA_TO_DEVICE);
77 i++;
78 }
79
80 dev_kfree_skb_any(skb);
81 }
82
83 iq->pkts_processed += compl_pkts;
84 iq->stats.instr_completed += compl_pkts;
85 iq->stats.bytes_sent += compl_bytes;
86 iq->stats.sgentry_sent += compl_sg;
87 iq->flush_index = fi;
88
89 netdev_tx_completed_queue(dev_queue: iq->netdev_q, pkts: compl_pkts, bytes: compl_bytes);
90
91 if (unlikely(__netif_subqueue_stopped(iq->netdev, iq->q_no)) &&
92 (IQ_INSTR_SPACE(iq) >
93 OCTEP_WAKE_QUEUE_THRESHOLD))
94 netif_wake_subqueue(dev: iq->netdev, queue_index: iq->q_no);
95 return !budget;
96}
97
98/**
99 * octep_iq_free_pending() - Free Tx buffers for pending completions.
100 *
101 * @iq: Octeon Tx queue data structure.
102 */
103static void octep_iq_free_pending(struct octep_iq *iq)
104{
105 struct octep_tx_buffer *tx_buffer;
106 struct skb_shared_info *shinfo;
107 u32 fi = iq->flush_index;
108 struct sk_buff *skb;
109 u8 frags, i;
110
111 while (fi != iq->host_write_index) {
112 tx_buffer = iq->buff_info + fi;
113 skb = tx_buffer->skb;
114
115 fi++;
116 if (unlikely(fi == iq->max_count))
117 fi = 0;
118
119 if (!tx_buffer->gather) {
120 dma_unmap_single(iq->dev, tx_buffer->dma,
121 tx_buffer->skb->len, DMA_TO_DEVICE);
122 dev_kfree_skb_any(skb);
123 continue;
124 }
125
126 /* Scatter/Gather */
127 shinfo = skb_shinfo(skb);
128 frags = shinfo->nr_frags;
129
130 dma_unmap_single(iq->dev,
131 tx_buffer->sglist[0].dma_ptr[0],
132 tx_buffer->sglist[0].len[3],
133 DMA_TO_DEVICE);
134
135 i = 1; /* entry 0 is main skb, unmapped above */
136 while (frags--) {
137 dma_unmap_page(iq->dev, tx_buffer->sglist[i >> 2].dma_ptr[i & 3],
138 tx_buffer->sglist[i >> 2].len[3 - (i & 3)], DMA_TO_DEVICE);
139 i++;
140 }
141
142 dev_kfree_skb_any(skb);
143 }
144
145 iq->flush_index = fi;
146 netdev_tx_reset_queue(q: netdev_get_tx_queue(dev: iq->netdev, index: iq->q_no));
147}
148
149/**
150 * octep_clean_iqs() - Clean Tx queues to shutdown the device.
151 *
152 * @oct: Octeon device private data structure.
153 *
154 * Free the buffers in Tx queue descriptors pending completion and
155 * reset queue indices
156 */
157void octep_clean_iqs(struct octep_device *oct)
158{
159 int i;
160
161 for (i = 0; i < oct->num_iqs; i++) {
162 octep_iq_free_pending(iq: oct->iq[i]);
163 octep_iq_reset_indices(iq: oct->iq[i]);
164 }
165}
166
167/**
168 * octep_setup_iq() - Setup a Tx queue.
169 *
170 * @oct: Octeon device private data structure.
171 * @q_no: Tx queue number to be setup.
172 *
173 * Allocate resources for a Tx queue.
174 */
175static int octep_setup_iq(struct octep_device *oct, int q_no)
176{
177 u32 desc_ring_size, buff_info_size, sglist_size;
178 struct octep_iq *iq;
179 int i;
180
181 iq = vzalloc(size: sizeof(*iq));
182 if (!iq)
183 goto iq_alloc_err;
184 oct->iq[q_no] = iq;
185
186 iq->octep_dev = oct;
187 iq->netdev = oct->netdev;
188 iq->dev = &oct->pdev->dev;
189 iq->q_no = q_no;
190 iq->max_count = CFG_GET_IQ_NUM_DESC(oct->conf);
191 iq->ring_size_mask = iq->max_count - 1;
192 iq->fill_threshold = CFG_GET_IQ_DB_MIN(oct->conf);
193 iq->netdev_q = netdev_get_tx_queue(dev: iq->netdev, index: q_no);
194
195 /* Allocate memory for hardware queue descriptors */
196 desc_ring_size = OCTEP_IQ_DESC_SIZE * CFG_GET_IQ_NUM_DESC(oct->conf);
197 iq->desc_ring = dma_alloc_coherent(dev: iq->dev, size: desc_ring_size,
198 dma_handle: &iq->desc_ring_dma, GFP_KERNEL);
199 if (unlikely(!iq->desc_ring)) {
200 dev_err(iq->dev,
201 "Failed to allocate DMA memory for IQ-%d\n", q_no);
202 goto desc_dma_alloc_err;
203 }
204
205 /* Allocate memory for hardware SGLIST descriptors */
206 sglist_size = OCTEP_SGLIST_SIZE_PER_PKT *
207 CFG_GET_IQ_NUM_DESC(oct->conf);
208 iq->sglist = dma_alloc_coherent(dev: iq->dev, size: sglist_size,
209 dma_handle: &iq->sglist_dma, GFP_KERNEL);
210 if (unlikely(!iq->sglist)) {
211 dev_err(iq->dev,
212 "Failed to allocate DMA memory for IQ-%d SGLIST\n",
213 q_no);
214 goto sglist_alloc_err;
215 }
216
217 /* allocate memory to manage Tx packets pending completion */
218 buff_info_size = OCTEP_IQ_TXBUFF_INFO_SIZE * iq->max_count;
219 iq->buff_info = vzalloc(size: buff_info_size);
220 if (!iq->buff_info) {
221 dev_err(iq->dev,
222 "Failed to allocate buff info for IQ-%d\n", q_no);
223 goto buff_info_err;
224 }
225
226 /* Setup sglist addresses in tx_buffer entries */
227 for (i = 0; i < CFG_GET_IQ_NUM_DESC(oct->conf); i++) {
228 struct octep_tx_buffer *tx_buffer;
229
230 tx_buffer = &iq->buff_info[i];
231 tx_buffer->sglist =
232 &iq->sglist[i * OCTEP_SGLIST_ENTRIES_PER_PKT];
233 tx_buffer->sglist_dma =
234 iq->sglist_dma + (i * OCTEP_SGLIST_SIZE_PER_PKT);
235 }
236
237 octep_iq_reset_indices(iq);
238 oct->hw_ops.setup_iq_regs(oct, q_no);
239
240 oct->num_iqs++;
241 return 0;
242
243buff_info_err:
244 dma_free_coherent(dev: iq->dev, size: sglist_size, cpu_addr: iq->sglist, dma_handle: iq->sglist_dma);
245sglist_alloc_err:
246 dma_free_coherent(dev: iq->dev, size: desc_ring_size,
247 cpu_addr: iq->desc_ring, dma_handle: iq->desc_ring_dma);
248desc_dma_alloc_err:
249 vfree(addr: iq);
250 oct->iq[q_no] = NULL;
251iq_alloc_err:
252 return -1;
253}
254
255/**
256 * octep_free_iq() - Free Tx queue resources.
257 *
258 * @iq: Octeon Tx queue data structure.
259 *
260 * Free all the resources allocated for a Tx queue.
261 */
262static void octep_free_iq(struct octep_iq *iq)
263{
264 struct octep_device *oct = iq->octep_dev;
265 u64 desc_ring_size, sglist_size;
266 int q_no = iq->q_no;
267
268 desc_ring_size = OCTEP_IQ_DESC_SIZE * CFG_GET_IQ_NUM_DESC(oct->conf);
269
270 vfree(addr: iq->buff_info);
271
272 if (iq->desc_ring)
273 dma_free_coherent(dev: iq->dev, size: desc_ring_size,
274 cpu_addr: iq->desc_ring, dma_handle: iq->desc_ring_dma);
275
276 sglist_size = OCTEP_SGLIST_SIZE_PER_PKT *
277 CFG_GET_IQ_NUM_DESC(oct->conf);
278 if (iq->sglist)
279 dma_free_coherent(dev: iq->dev, size: sglist_size,
280 cpu_addr: iq->sglist, dma_handle: iq->sglist_dma);
281
282 vfree(addr: iq);
283 oct->iq[q_no] = NULL;
284 oct->num_iqs--;
285}
286
287/**
288 * octep_setup_iqs() - setup resources for all Tx queues.
289 *
290 * @oct: Octeon device private data structure.
291 */
292int octep_setup_iqs(struct octep_device *oct)
293{
294 int i;
295
296 oct->num_iqs = 0;
297 for (i = 0; i < CFG_GET_PORTS_ACTIVE_IO_RINGS(oct->conf); i++) {
298 if (octep_setup_iq(oct, q_no: i)) {
299 dev_err(&oct->pdev->dev,
300 "Failed to setup IQ(TxQ)-%d.\n", i);
301 goto iq_setup_err;
302 }
303 dev_dbg(&oct->pdev->dev, "Successfully setup IQ(TxQ)-%d.\n", i);
304 }
305
306 return 0;
307
308iq_setup_err:
309 while (i) {
310 i--;
311 octep_free_iq(iq: oct->iq[i]);
312 }
313 return -1;
314}
315
316/**
317 * octep_free_iqs() - Free resources of all Tx queues.
318 *
319 * @oct: Octeon device private data structure.
320 */
321void octep_free_iqs(struct octep_device *oct)
322{
323 int i;
324
325 for (i = 0; i < CFG_GET_PORTS_ACTIVE_IO_RINGS(oct->conf); i++) {
326 octep_free_iq(iq: oct->iq[i]);
327 dev_dbg(&oct->pdev->dev,
328 "Successfully destroyed IQ(TxQ)-%d.\n", i);
329 }
330 oct->num_iqs = 0;
331}
332

source code of linux/drivers/net/ethernet/marvell/octeon_ep/octep_tx.c