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 #define LOG_CATEGORY UCLASS_VIRTIO
8 
9 #include <common.h>
10 #include <blk.h>
11 #include <dm.h>
12 #include <part.h>
13 #include <virtio_types.h>
14 #include <virtio.h>
15 #include <virtio_ring.h>
16 #include "virtio_blk.h"
17 
18 struct virtio_blk_priv {
19 	struct virtqueue *vq;
20 };
21 
virtio_blk_do_req(struct udevice * dev,u64 sector,lbaint_t blkcnt,void * buffer,u32 type)22 static ulong virtio_blk_do_req(struct udevice *dev, u64 sector,
23 			       lbaint_t blkcnt, void *buffer, u32 type)
24 {
25 	struct virtio_blk_priv *priv = dev_get_priv(dev);
26 	unsigned int num_out = 0, num_in = 0;
27 	struct virtio_sg *sgs[3];
28 	u8 status;
29 	int ret;
30 
31 	struct virtio_blk_outhdr out_hdr = {
32 		.type = cpu_to_virtio32(dev, type),
33 		.sector = cpu_to_virtio64(dev, sector),
34 	};
35 	struct virtio_sg hdr_sg = { &out_hdr, sizeof(out_hdr) };
36 	struct virtio_sg data_sg = { buffer, blkcnt * 512 };
37 	struct virtio_sg status_sg = { &status, sizeof(status) };
38 
39 	sgs[num_out++] = &hdr_sg;
40 
41 	if (type & VIRTIO_BLK_T_OUT)
42 		sgs[num_out++] = &data_sg;
43 	else
44 		sgs[num_out + num_in++] = &data_sg;
45 
46 	sgs[num_out + num_in++] = &status_sg;
47 	log_debug("dev=%s, active=%d, priv=%p, priv->vq=%p\n", dev->name,
48 		  device_active(dev), priv, priv->vq);
49 
50 	ret = virtqueue_add(priv->vq, sgs, num_out, num_in);
51 	if (ret)
52 		return ret;
53 
54 	virtqueue_kick(priv->vq);
55 
56 	log_debug("wait...");
57 	while (!virtqueue_get_buf(priv->vq, NULL))
58 		;
59 	log_debug("done\n");
60 
61 	return status == VIRTIO_BLK_S_OK ? blkcnt : -EIO;
62 }
63 
virtio_blk_read(struct udevice * dev,lbaint_t start,lbaint_t blkcnt,void * buffer)64 static ulong virtio_blk_read(struct udevice *dev, lbaint_t start,
65 			     lbaint_t blkcnt, void *buffer)
66 {
67 	log_debug("read %s\n", dev->name);
68 	return virtio_blk_do_req(dev, start, blkcnt, buffer,
69 				 VIRTIO_BLK_T_IN);
70 }
71 
virtio_blk_write(struct udevice * dev,lbaint_t start,lbaint_t blkcnt,const void * buffer)72 static ulong virtio_blk_write(struct udevice *dev, lbaint_t start,
73 			      lbaint_t blkcnt, const void *buffer)
74 {
75 	return virtio_blk_do_req(dev, start, blkcnt, (void *)buffer,
76 				 VIRTIO_BLK_T_OUT);
77 }
78 
virtio_blk_bind(struct udevice * dev)79 static int virtio_blk_bind(struct udevice *dev)
80 {
81 	struct virtio_dev_priv *uc_priv = dev_get_uclass_priv(dev->parent);
82 	struct blk_desc *desc = dev_get_uclass_plat(dev);
83 	int devnum;
84 
85 	desc->uclass_id = UCLASS_VIRTIO;
86 	/*
87 	 * Initialize the devnum to -ENODEV. This is to make sure that
88 	 * blk_next_free_devnum() works as expected, since the default
89 	 * value 0 is a valid devnum.
90 	 */
91 	desc->devnum = -ENODEV;
92 	devnum = blk_next_free_devnum(UCLASS_VIRTIO);
93 	if (devnum < 0)
94 		return devnum;
95 	desc->devnum = devnum;
96 	desc->part_type = PART_TYPE_UNKNOWN;
97 	/*
98 	 * virtio mmio transport supplies string identification for us,
99 	 * while pci trnasport uses a 2-byte subvendor value.
100 	 */
101 	if (uc_priv->vendor >> 16)
102 		sprintf(desc->vendor, "%s", (char *)&uc_priv->vendor);
103 	else
104 		sprintf(desc->vendor, "%04x", uc_priv->vendor);
105 	desc->bdev = dev;
106 
107 	/* Indicate what driver features we support */
108 	virtio_driver_features_init(uc_priv, NULL, 0, NULL, 0);
109 
110 	return 0;
111 }
112 
virtio_blk_probe(struct udevice * dev)113 static int virtio_blk_probe(struct udevice *dev)
114 {
115 	struct virtio_blk_priv *priv = dev_get_priv(dev);
116 	struct blk_desc *desc = dev_get_uclass_plat(dev);
117 	u64 cap;
118 	int ret;
119 
120 	ret = virtio_find_vqs(dev, 1, &priv->vq);
121 	if (ret)
122 		return ret;
123 
124 	desc->blksz = 512;
125 	desc->log2blksz = 9;
126 	virtio_cread(dev, struct virtio_blk_config, capacity, &cap);
127 	desc->lba = cap;
128 
129 	return 0;
130 }
131 
132 static const struct blk_ops virtio_blk_ops = {
133 	.read	= virtio_blk_read,
134 	.write	= virtio_blk_write,
135 };
136 
137 U_BOOT_DRIVER(virtio_blk) = {
138 	.name	= VIRTIO_BLK_DRV_NAME,
139 	.id	= UCLASS_BLK,
140 	.ops	= &virtio_blk_ops,
141 	.bind	= virtio_blk_bind,
142 	.probe	= virtio_blk_probe,
143 	.remove	= virtio_reset,
144 	.priv_auto	= sizeof(struct virtio_blk_priv),
145 	.flags	= DM_FLAG_ACTIVE_DMA,
146 };
147