xref: /openbmc/qemu/hw/usb/libhw.c (revision b52df465)
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-common.h"
23 #include "hw/hw.h"
24 #include "hw/usb.h"
25 #include "sysemu/dma.h"
26 
27 int usb_packet_map(USBPacket *p, QEMUSGList *sgl)
28 {
29     DMADirection dir = (p->pid == USB_TOKEN_IN) ?
30         DMA_DIRECTION_FROM_DEVICE : DMA_DIRECTION_TO_DEVICE;
31     void *mem;
32     int i;
33 
34     for (i = 0; i < sgl->nsg; i++) {
35         dma_addr_t base = sgl->sg[i].base;
36         dma_addr_t len = sgl->sg[i].len;
37 
38         while (len) {
39             dma_addr_t xlen = len;
40             mem = dma_memory_map(sgl->as, base, &xlen, dir);
41             if (!mem) {
42                 goto err;
43             }
44             if (xlen > len) {
45                 xlen = len;
46             }
47             qemu_iovec_add(&p->iov, mem, xlen);
48             len -= xlen;
49             base += xlen;
50         }
51     }
52     return 0;
53 
54 err:
55     usb_packet_unmap(p, sgl);
56     return -1;
57 }
58 
59 void usb_packet_unmap(USBPacket *p, QEMUSGList *sgl)
60 {
61     DMADirection dir = (p->pid == USB_TOKEN_IN) ?
62         DMA_DIRECTION_FROM_DEVICE : DMA_DIRECTION_TO_DEVICE;
63     int i;
64 
65     for (i = 0; i < p->iov.niov; i++) {
66         dma_memory_unmap(sgl->as, p->iov.iov[i].iov_base,
67                          p->iov.iov[i].iov_len, dir,
68                          p->iov.iov[i].iov_len);
69     }
70 }
71