Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0
2/* Copyright (C) 2018-2025, Advanced Micro Devices, Inc. */
3
4#include <linux/dma-mapping.h>
5
6#include "ionic_queue.h"
7
8int ionic_queue_init(struct ionic_queue *q, struct device *dma_dev,
9 int depth, size_t stride)
10{
11 if (depth < 0 || depth > 0xffff)
12 return -EINVAL;
13
14 if (stride == 0 || stride > 0x10000)
15 return -EINVAL;
16
17 if (depth == 0)
18 depth = 1;
19
20 q->depth_log2 = order_base_2(depth + 1);
21 q->stride_log2 = order_base_2(stride);
22
23 if (q->depth_log2 + q->stride_log2 < PAGE_SHIFT)
24 q->depth_log2 = PAGE_SHIFT - q->stride_log2;
25
26 if (q->depth_log2 > 16 || q->stride_log2 > 16)
27 return -EINVAL;
28
29 q->size = BIT_ULL(q->depth_log2 + q->stride_log2);
30 q->mask = BIT(q->depth_log2) - 1;
31
32 q->ptr = dma_alloc_coherent(dma_dev, q->size, &q->dma, GFP_KERNEL);
33 if (!q->ptr)
34 return -ENOMEM;
35
36 /* it will always be page aligned, but just to be sure... */
37 if (!PAGE_ALIGNED(q->ptr)) {
38 dma_free_coherent(dma_dev, q->size, q->ptr, q->dma);
39 return -ENOMEM;
40 }
41
42 q->prod = 0;
43 q->cons = 0;
44 q->dbell = 0;
45
46 return 0;
47}
48
49void ionic_queue_destroy(struct ionic_queue *q, struct device *dma_dev)
50{
51 dma_free_coherent(dma_dev, q->size, q->ptr, q->dma);
52}