xref: /openbmc/linux/drivers/crypto/qce/dma.c (revision e1cd7b80)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2012-2014, The Linux Foundation. All rights reserved.
4  */
5 
6 #include <linux/dmaengine.h>
7 #include <crypto/scatterwalk.h>
8 
9 #include "dma.h"
10 
11 int qce_dma_request(struct device *dev, struct qce_dma_data *dma)
12 {
13 	int ret;
14 
15 	dma->txchan = dma_request_chan(dev, "tx");
16 	if (IS_ERR(dma->txchan))
17 		return PTR_ERR(dma->txchan);
18 
19 	dma->rxchan = dma_request_chan(dev, "rx");
20 	if (IS_ERR(dma->rxchan)) {
21 		ret = PTR_ERR(dma->rxchan);
22 		goto error_rx;
23 	}
24 
25 	dma->result_buf = kmalloc(QCE_RESULT_BUF_SZ + QCE_IGNORE_BUF_SZ,
26 				  GFP_KERNEL);
27 	if (!dma->result_buf) {
28 		ret = -ENOMEM;
29 		goto error_nomem;
30 	}
31 
32 	dma->ignore_buf = dma->result_buf + QCE_RESULT_BUF_SZ;
33 
34 	return 0;
35 error_nomem:
36 	dma_release_channel(dma->rxchan);
37 error_rx:
38 	dma_release_channel(dma->txchan);
39 	return ret;
40 }
41 
42 void qce_dma_release(struct qce_dma_data *dma)
43 {
44 	dma_release_channel(dma->txchan);
45 	dma_release_channel(dma->rxchan);
46 	kfree(dma->result_buf);
47 }
48 
49 struct scatterlist *
50 qce_sgtable_add(struct sg_table *sgt, struct scatterlist *new_sgl)
51 {
52 	struct scatterlist *sg = sgt->sgl, *sg_last = NULL;
53 
54 	while (sg) {
55 		if (!sg_page(sg))
56 			break;
57 		sg = sg_next(sg);
58 	}
59 
60 	if (!sg)
61 		return ERR_PTR(-EINVAL);
62 
63 	while (new_sgl && sg) {
64 		sg_set_page(sg, sg_page(new_sgl), new_sgl->length,
65 			    new_sgl->offset);
66 		sg_last = sg;
67 		sg = sg_next(sg);
68 		new_sgl = sg_next(new_sgl);
69 	}
70 
71 	return sg_last;
72 }
73 
74 static int qce_dma_prep_sg(struct dma_chan *chan, struct scatterlist *sg,
75 			   int nents, unsigned long flags,
76 			   enum dma_transfer_direction dir,
77 			   dma_async_tx_callback cb, void *cb_param)
78 {
79 	struct dma_async_tx_descriptor *desc;
80 	dma_cookie_t cookie;
81 
82 	if (!sg || !nents)
83 		return -EINVAL;
84 
85 	desc = dmaengine_prep_slave_sg(chan, sg, nents, dir, flags);
86 	if (!desc)
87 		return -EINVAL;
88 
89 	desc->callback = cb;
90 	desc->callback_param = cb_param;
91 	cookie = dmaengine_submit(desc);
92 
93 	return dma_submit_error(cookie);
94 }
95 
96 int qce_dma_prep_sgs(struct qce_dma_data *dma, struct scatterlist *rx_sg,
97 		     int rx_nents, struct scatterlist *tx_sg, int tx_nents,
98 		     dma_async_tx_callback cb, void *cb_param)
99 {
100 	struct dma_chan *rxchan = dma->rxchan;
101 	struct dma_chan *txchan = dma->txchan;
102 	unsigned long flags = DMA_PREP_INTERRUPT | DMA_CTRL_ACK;
103 	int ret;
104 
105 	ret = qce_dma_prep_sg(rxchan, rx_sg, rx_nents, flags, DMA_MEM_TO_DEV,
106 			     NULL, NULL);
107 	if (ret)
108 		return ret;
109 
110 	return qce_dma_prep_sg(txchan, tx_sg, tx_nents, flags, DMA_DEV_TO_MEM,
111 			       cb, cb_param);
112 }
113 
114 void qce_dma_issue_pending(struct qce_dma_data *dma)
115 {
116 	dma_async_issue_pending(dma->rxchan);
117 	dma_async_issue_pending(dma->txchan);
118 }
119 
120 int qce_dma_terminate_all(struct qce_dma_data *dma)
121 {
122 	int ret;
123 
124 	ret = dmaengine_terminate_all(dma->rxchan);
125 	return ret ?: dmaengine_terminate_all(dma->txchan);
126 }
127