xref: /linux/drivers/crypto/qce/dma.c (revision a619fe35ab41fded440d3762d4fbad84ff86a4d4)
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/device.h>
7 #include <linux/dmaengine.h>
8 #include <crypto/scatterwalk.h>
9 
10 #include "dma.h"
11 
qce_dma_release(void * data)12 static void qce_dma_release(void *data)
13 {
14 	struct qce_dma_data *dma = data;
15 
16 	dma_release_channel(dma->txchan);
17 	dma_release_channel(dma->rxchan);
18 	kfree(dma->result_buf);
19 }
20 
devm_qce_dma_request(struct device * dev,struct qce_dma_data * dma)21 int devm_qce_dma_request(struct device *dev, struct qce_dma_data *dma)
22 {
23 	int ret;
24 
25 	dma->txchan = dma_request_chan(dev, "tx");
26 	if (IS_ERR(dma->txchan))
27 		return dev_err_probe(dev, PTR_ERR(dma->txchan),
28 				     "Failed to get TX DMA channel\n");
29 
30 	dma->rxchan = dma_request_chan(dev, "rx");
31 	if (IS_ERR(dma->rxchan)) {
32 		ret = dev_err_probe(dev, PTR_ERR(dma->rxchan),
33 				    "Failed to get RX DMA channel\n");
34 		goto error_rx;
35 	}
36 
37 	dma->result_buf = kmalloc(QCE_RESULT_BUF_SZ + QCE_IGNORE_BUF_SZ,
38 				  GFP_KERNEL);
39 	if (!dma->result_buf) {
40 		ret = -ENOMEM;
41 		goto error_nomem;
42 	}
43 
44 	dma->ignore_buf = dma->result_buf + QCE_RESULT_BUF_SZ;
45 
46 	return devm_add_action_or_reset(dev, qce_dma_release, dma);
47 
48 error_nomem:
49 	dma_release_channel(dma->rxchan);
50 error_rx:
51 	dma_release_channel(dma->txchan);
52 	return ret;
53 }
54 
55 struct scatterlist *
qce_sgtable_add(struct sg_table * sgt,struct scatterlist * new_sgl,unsigned int max_len)56 qce_sgtable_add(struct sg_table *sgt, struct scatterlist *new_sgl,
57 		unsigned int max_len)
58 {
59 	struct scatterlist *sg = sgt->sgl, *sg_last = NULL;
60 	unsigned int new_len;
61 
62 	while (sg) {
63 		if (!sg_page(sg))
64 			break;
65 		sg = sg_next(sg);
66 	}
67 
68 	if (!sg)
69 		return ERR_PTR(-EINVAL);
70 
71 	while (new_sgl && sg && max_len) {
72 		new_len = new_sgl->length > max_len ? max_len : new_sgl->length;
73 		sg_set_page(sg, sg_page(new_sgl), new_len, new_sgl->offset);
74 		sg_last = sg;
75 		sg = sg_next(sg);
76 		new_sgl = sg_next(new_sgl);
77 		max_len -= new_len;
78 	}
79 
80 	return sg_last;
81 }
82 
qce_dma_prep_sg(struct dma_chan * chan,struct scatterlist * sg,int nents,unsigned long flags,enum dma_transfer_direction dir,dma_async_tx_callback cb,void * cb_param)83 static int qce_dma_prep_sg(struct dma_chan *chan, struct scatterlist *sg,
84 			   int nents, unsigned long flags,
85 			   enum dma_transfer_direction dir,
86 			   dma_async_tx_callback cb, void *cb_param)
87 {
88 	struct dma_async_tx_descriptor *desc;
89 	dma_cookie_t cookie;
90 
91 	if (!sg || !nents)
92 		return -EINVAL;
93 
94 	desc = dmaengine_prep_slave_sg(chan, sg, nents, dir, flags);
95 	if (!desc)
96 		return -EINVAL;
97 
98 	desc->callback = cb;
99 	desc->callback_param = cb_param;
100 	cookie = dmaengine_submit(desc);
101 
102 	return dma_submit_error(cookie);
103 }
104 
qce_dma_prep_sgs(struct qce_dma_data * dma,struct scatterlist * rx_sg,int rx_nents,struct scatterlist * tx_sg,int tx_nents,dma_async_tx_callback cb,void * cb_param)105 int qce_dma_prep_sgs(struct qce_dma_data *dma, struct scatterlist *rx_sg,
106 		     int rx_nents, struct scatterlist *tx_sg, int tx_nents,
107 		     dma_async_tx_callback cb, void *cb_param)
108 {
109 	struct dma_chan *rxchan = dma->rxchan;
110 	struct dma_chan *txchan = dma->txchan;
111 	unsigned long flags = DMA_PREP_INTERRUPT | DMA_CTRL_ACK;
112 	int ret;
113 
114 	ret = qce_dma_prep_sg(rxchan, rx_sg, rx_nents, flags, DMA_MEM_TO_DEV,
115 			     NULL, NULL);
116 	if (ret)
117 		return ret;
118 
119 	return qce_dma_prep_sg(txchan, tx_sg, tx_nents, flags, DMA_DEV_TO_MEM,
120 			       cb, cb_param);
121 }
122 
qce_dma_issue_pending(struct qce_dma_data * dma)123 void qce_dma_issue_pending(struct qce_dma_data *dma)
124 {
125 	dma_async_issue_pending(dma->rxchan);
126 	dma_async_issue_pending(dma->txchan);
127 }
128 
qce_dma_terminate_all(struct qce_dma_data * dma)129 int qce_dma_terminate_all(struct qce_dma_data *dma)
130 {
131 	int ret;
132 
133 	ret = dmaengine_terminate_all(dma->rxchan);
134 	return ret ?: dmaengine_terminate_all(dma->txchan);
135 }
136