1 /* SPDX-License-Identifier: GPL-2.0 */
2 /* Copyright (c) Huawei Technologies Co., Ltd. 2025. All rights reserved. */
3
4 #ifndef _HINIC3_QUEUE_COMMON_H_
5 #define _HINIC3_QUEUE_COMMON_H_
6
7 #include <linux/types.h>
8
9 #include "hinic3_common.h"
10
11 struct hinic3_hwdev;
12
13 struct hinic3_queue_pages {
14 /* Array of DMA-able pages that actually holds the queue entries. */
15 struct hinic3_dma_addr_align *pages;
16 /* Page size in bytes. */
17 u32 page_size;
18 /* Number of pages, must be power of 2. */
19 u16 num_pages;
20 u8 elem_size_shift;
21 u8 elem_per_pg_shift;
22 };
23
24 void hinic3_queue_pages_init(struct hinic3_queue_pages *qpages, u32 q_depth,
25 u32 page_size, u32 elem_size);
26 int hinic3_queue_pages_alloc(struct hinic3_hwdev *hwdev,
27 struct hinic3_queue_pages *qpages, u32 align);
28 void hinic3_queue_pages_free(struct hinic3_hwdev *hwdev,
29 struct hinic3_queue_pages *qpages);
30
31 /* Get pointer to queue entry at the specified index. Index does not have to be
32 * masked to queue depth, only least significant bits will be used. Also
33 * provides remaining elements in same page (including the first one) in case
34 * caller needs multiple entries.
35 */
get_q_element(const struct hinic3_queue_pages * qpages,u32 idx,u32 * remaining_in_page)36 static inline void *get_q_element(const struct hinic3_queue_pages *qpages,
37 u32 idx, u32 *remaining_in_page)
38 {
39 const struct hinic3_dma_addr_align *page;
40 u32 page_idx, elem_idx, elem_per_pg, ofs;
41 u8 shift;
42
43 shift = qpages->elem_per_pg_shift;
44 page_idx = (idx >> shift) & (qpages->num_pages - 1);
45 elem_per_pg = 1 << shift;
46 elem_idx = idx & (elem_per_pg - 1);
47 if (remaining_in_page)
48 *remaining_in_page = elem_per_pg - elem_idx;
49 ofs = elem_idx << qpages->elem_size_shift;
50 page = qpages->pages + page_idx;
51 return (char *)page->align_vaddr + ofs;
52 }
53
54 #endif
55