1 // SPDX-License-Identifier: GPL-2.0+
2
3 #include "fdma_api.h"
4
5 #include <linux/bits.h>
6 #include <linux/etherdevice.h>
7 #include <linux/types.h>
8
9 /* Add a DB to a DCB, providing a callback for getting the DB dataptr. */
__fdma_db_add(struct fdma * fdma,int dcb_idx,int db_idx,u64 status,int (* cb)(struct fdma * fdma,int dcb_idx,int db_idx,u64 * dataptr))10 static int __fdma_db_add(struct fdma *fdma, int dcb_idx, int db_idx, u64 status,
11 int (*cb)(struct fdma *fdma, int dcb_idx,
12 int db_idx, u64 *dataptr))
13 {
14 struct fdma_db *db = fdma_db_get(fdma, dcb_idx, db_idx);
15
16 db->status = status;
17
18 return cb(fdma, dcb_idx, db_idx, &db->dataptr);
19 }
20
21 /* Add a DB to a DCB, using the callback set in the fdma_ops struct. */
fdma_db_add(struct fdma * fdma,int dcb_idx,int db_idx,u64 status)22 int fdma_db_add(struct fdma *fdma, int dcb_idx, int db_idx, u64 status)
23 {
24 return __fdma_db_add(fdma,
25 dcb_idx,
26 db_idx,
27 status,
28 fdma->ops.dataptr_cb);
29 }
30
31 /* Add a DCB with callbacks for getting the DB dataptr and the DCB nextptr. */
__fdma_dcb_add(struct fdma * fdma,int dcb_idx,u64 info,u64 status,int (* dcb_cb)(struct fdma * fdma,int dcb_idx,u64 * nextptr),int (* db_cb)(struct fdma * fdma,int dcb_idx,int db_idx,u64 * dataptr))32 int __fdma_dcb_add(struct fdma *fdma, int dcb_idx, u64 info, u64 status,
33 int (*dcb_cb)(struct fdma *fdma, int dcb_idx, u64 *nextptr),
34 int (*db_cb)(struct fdma *fdma, int dcb_idx, int db_idx,
35 u64 *dataptr))
36 {
37 struct fdma_dcb *dcb = fdma_dcb_get(fdma, dcb_idx);
38 int i, err;
39
40 for (i = 0; i < fdma->n_dbs; i++) {
41 err = __fdma_db_add(fdma, dcb_idx, i, status, db_cb);
42 if (unlikely(err))
43 return err;
44 }
45
46 err = dcb_cb(fdma, dcb_idx, &fdma->last_dcb->nextptr);
47 if (unlikely(err))
48 return err;
49
50 fdma->last_dcb = dcb;
51
52 dcb->nextptr = FDMA_DCB_INVALID_DATA;
53 dcb->info = info;
54
55 return 0;
56 }
57 EXPORT_SYMBOL_GPL(__fdma_dcb_add);
58
59 /* Add a DCB, using the preset callbacks in the fdma_ops struct. */
fdma_dcb_add(struct fdma * fdma,int dcb_idx,u64 info,u64 status)60 int fdma_dcb_add(struct fdma *fdma, int dcb_idx, u64 info, u64 status)
61 {
62 return __fdma_dcb_add(fdma,
63 dcb_idx,
64 info, status,
65 fdma->ops.nextptr_cb,
66 fdma->ops.dataptr_cb);
67 }
68 EXPORT_SYMBOL_GPL(fdma_dcb_add);
69
70 /* Initialize the DCB's and DB's. */
fdma_dcbs_init(struct fdma * fdma,u64 info,u64 status)71 int fdma_dcbs_init(struct fdma *fdma, u64 info, u64 status)
72 {
73 int i, err;
74
75 fdma->last_dcb = fdma->dcbs;
76 fdma->db_index = 0;
77 fdma->dcb_index = 0;
78
79 for (i = 0; i < fdma->n_dcbs; i++) {
80 err = fdma_dcb_add(fdma, i, info, status);
81 if (err)
82 return err;
83 }
84
85 return 0;
86 }
87 EXPORT_SYMBOL_GPL(fdma_dcbs_init);
88
89 /* Allocate coherent DMA memory for FDMA. */
fdma_alloc_coherent(struct device * dev,struct fdma * fdma)90 int fdma_alloc_coherent(struct device *dev, struct fdma *fdma)
91 {
92 fdma->dcbs = dma_alloc_coherent(dev,
93 fdma->size,
94 &fdma->dma,
95 GFP_KERNEL);
96 if (!fdma->dcbs)
97 return -ENOMEM;
98
99 return 0;
100 }
101 EXPORT_SYMBOL_GPL(fdma_alloc_coherent);
102
103 /* Allocate physical memory for FDMA. */
fdma_alloc_phys(struct fdma * fdma)104 int fdma_alloc_phys(struct fdma *fdma)
105 {
106 fdma->dcbs = kzalloc(fdma->size, GFP_KERNEL);
107 if (!fdma->dcbs)
108 return -ENOMEM;
109
110 fdma->dma = virt_to_phys(fdma->dcbs);
111
112 return 0;
113 }
114 EXPORT_SYMBOL_GPL(fdma_alloc_phys);
115
116 /* Free coherent DMA memory. */
fdma_free_coherent(struct device * dev,struct fdma * fdma)117 void fdma_free_coherent(struct device *dev, struct fdma *fdma)
118 {
119 dma_free_coherent(dev, fdma->size, fdma->dcbs, fdma->dma);
120 }
121 EXPORT_SYMBOL_GPL(fdma_free_coherent);
122
123 /* Free virtual memory. */
fdma_free_phys(struct fdma * fdma)124 void fdma_free_phys(struct fdma *fdma)
125 {
126 kfree(fdma->dcbs);
127 }
128 EXPORT_SYMBOL_GPL(fdma_free_phys);
129
130 /* Get the size of the FDMA memory */
fdma_get_size(struct fdma * fdma)131 u32 fdma_get_size(struct fdma *fdma)
132 {
133 return ALIGN(sizeof(struct fdma_dcb) * fdma->n_dcbs, PAGE_SIZE);
134 }
135 EXPORT_SYMBOL_GPL(fdma_get_size);
136
137 /* Get the size of the FDMA memory. This function is only applicable if the
138 * dataptr addresses and DCB's are in contiguous memory.
139 */
fdma_get_size_contiguous(struct fdma * fdma)140 u32 fdma_get_size_contiguous(struct fdma *fdma)
141 {
142 return ALIGN(fdma->n_dcbs * sizeof(struct fdma_dcb) +
143 fdma->n_dcbs * fdma->n_dbs * fdma->db_size,
144 PAGE_SIZE);
145 }
146 EXPORT_SYMBOL_GPL(fdma_get_size_contiguous);
147