1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2018, Tuomas Tynkkynen <tuomas.tynkkynen@iki.fi>
4 * Copyright (C) 2018, Bin Meng <bmeng.cn@gmail.com>
5 */
6
7 #include <common.h>
8 #include <blk.h>
9 #include <dm.h>
10 #include <virtio_types.h>
11 #include <virtio.h>
12 #include <virtio_ring.h>
13 #include "virtio_blk.h"
14
15 struct virtio_blk_priv {
16 struct virtqueue *vq;
17 };
18
virtio_blk_do_req(struct udevice * dev,u64 sector,lbaint_t blkcnt,void * buffer,u32 type)19 static ulong virtio_blk_do_req(struct udevice *dev, u64 sector,
20 lbaint_t blkcnt, void *buffer, u32 type)
21 {
22 struct virtio_blk_priv *priv = dev_get_priv(dev);
23 unsigned int num_out = 0, num_in = 0;
24 struct virtio_sg *sgs[3];
25 u8 status;
26 int ret;
27
28 struct virtio_blk_outhdr out_hdr = {
29 .type = cpu_to_virtio32(dev, type),
30 .sector = cpu_to_virtio64(dev, sector),
31 };
32 struct virtio_sg hdr_sg = { &out_hdr, sizeof(out_hdr) };
33 struct virtio_sg data_sg = { buffer, blkcnt * 512 };
34 struct virtio_sg status_sg = { &status, sizeof(status) };
35
36 sgs[num_out++] = &hdr_sg;
37
38 if (type & VIRTIO_BLK_T_OUT)
39 sgs[num_out++] = &data_sg;
40 else
41 sgs[num_out + num_in++] = &data_sg;
42
43 sgs[num_out + num_in++] = &status_sg;
44
45 ret = virtqueue_add(priv->vq, sgs, num_out, num_in);
46 if (ret)
47 return ret;
48
49 virtqueue_kick(priv->vq);
50
51 while (!virtqueue_get_buf(priv->vq, NULL))
52 ;
53
54 return status == VIRTIO_BLK_S_OK ? blkcnt : -EIO;
55 }
56
virtio_blk_read(struct udevice * dev,lbaint_t start,lbaint_t blkcnt,void * buffer)57 static ulong virtio_blk_read(struct udevice *dev, lbaint_t start,
58 lbaint_t blkcnt, void *buffer)
59 {
60 return virtio_blk_do_req(dev, start, blkcnt, buffer,
61 VIRTIO_BLK_T_IN);
62 }
63
virtio_blk_write(struct udevice * dev,lbaint_t start,lbaint_t blkcnt,const void * buffer)64 static ulong virtio_blk_write(struct udevice *dev, lbaint_t start,
65 lbaint_t blkcnt, const void *buffer)
66 {
67 return virtio_blk_do_req(dev, start, blkcnt, (void *)buffer,
68 VIRTIO_BLK_T_OUT);
69 }
70
virtio_blk_bind(struct udevice * dev)71 static int virtio_blk_bind(struct udevice *dev)
72 {
73 struct virtio_dev_priv *uc_priv = dev_get_uclass_priv(dev->parent);
74 struct blk_desc *desc = dev_get_uclass_platdata(dev);
75 int devnum;
76
77 desc->if_type = IF_TYPE_VIRTIO;
78 /*
79 * Initialize the devnum to -ENODEV. This is to make sure that
80 * blk_next_free_devnum() works as expected, since the default
81 * value 0 is a valid devnum.
82 */
83 desc->devnum = -ENODEV;
84 devnum = blk_next_free_devnum(IF_TYPE_VIRTIO);
85 if (devnum < 0)
86 return devnum;
87 desc->devnum = devnum;
88 desc->part_type = PART_TYPE_UNKNOWN;
89 /*
90 * virtio mmio transport supplies string identification for us,
91 * while pci trnasport uses a 2-byte subvendor value.
92 */
93 if (uc_priv->vendor >> 16)
94 sprintf(desc->vendor, "%s", (char *)&uc_priv->vendor);
95 else
96 sprintf(desc->vendor, "%04x", uc_priv->vendor);
97 desc->bdev = dev;
98
99 /* Indicate what driver features we support */
100 virtio_driver_features_init(uc_priv, NULL, 0, NULL, 0);
101
102 return 0;
103 }
104
virtio_blk_probe(struct udevice * dev)105 static int virtio_blk_probe(struct udevice *dev)
106 {
107 struct virtio_blk_priv *priv = dev_get_priv(dev);
108 struct blk_desc *desc = dev_get_uclass_platdata(dev);
109 u64 cap;
110 int ret;
111
112 ret = virtio_find_vqs(dev, 1, &priv->vq);
113 if (ret)
114 return ret;
115
116 desc->blksz = 512;
117 virtio_cread(dev, struct virtio_blk_config, capacity, &cap);
118 desc->lba = cap;
119
120 return 0;
121 }
122
123 static const struct blk_ops virtio_blk_ops = {
124 .read = virtio_blk_read,
125 .write = virtio_blk_write,
126 };
127
128 U_BOOT_DRIVER(virtio_blk) = {
129 .name = VIRTIO_BLK_DRV_NAME,
130 .id = UCLASS_BLK,
131 .ops = &virtio_blk_ops,
132 .bind = virtio_blk_bind,
133 .probe = virtio_blk_probe,
134 .remove = virtio_reset,
135 .priv_auto_alloc_size = sizeof(struct virtio_blk_priv),
136 .flags = DM_FLAG_ACTIVE_DMA,
137 };
138