xref: /openbmc/qemu/hw/usb/libhw.c (revision f6476697)
1 /*
2  * QEMU USB emulation, libhw bits.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a copy
5  * of this software and associated documentation files (the "Software"), to deal
6  * in the Software without restriction, including without limitation the rights
7  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
8  * copies of the Software, and to permit persons to whom the Software is
9  * furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
17  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
19  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
20  * THE SOFTWARE.
21  */
22 #include "qemu/osdep.h"
23 #include "hw/usb.h"
24 #include "sysemu/dma.h"
25 
26 int usb_packet_map(USBPacket *p, QEMUSGList *sgl)
27 {
28     DMADirection dir = (p->pid == USB_TOKEN_IN) ?
29         DMA_DIRECTION_FROM_DEVICE : DMA_DIRECTION_TO_DEVICE;
30     void *mem;
31     int i;
32 
33     for (i = 0; i < sgl->nsg; i++) {
34         dma_addr_t base = sgl->sg[i].base;
35         dma_addr_t len = sgl->sg[i].len;
36 
37         while (len) {
38             dma_addr_t xlen = len;
39             mem = dma_memory_map(sgl->as, base, &xlen, dir);
40             if (!mem) {
41                 goto err;
42             }
43             if (xlen > len) {
44                 xlen = len;
45             }
46             qemu_iovec_add(&p->iov, mem, xlen);
47             len -= xlen;
48             base += xlen;
49         }
50     }
51     return 0;
52 
53 err:
54     usb_packet_unmap(p, sgl);
55     return -1;
56 }
57 
58 void usb_packet_unmap(USBPacket *p, QEMUSGList *sgl)
59 {
60     DMADirection dir = (p->pid == USB_TOKEN_IN) ?
61         DMA_DIRECTION_FROM_DEVICE : DMA_DIRECTION_TO_DEVICE;
62     int i;
63 
64     for (i = 0; i < p->iov.niov; i++) {
65         dma_memory_unmap(sgl->as, p->iov.iov[i].iov_base,
66                          p->iov.iov[i].iov_len, dir,
67                          p->iov.iov[i].iov_len);
68     }
69 }
70