1 /*
2 * Remote IO Hub
3 *
4 * Copyright © 2018, 2021 Oracle and/or its affiliates.
5 *
6 * This work is licensed under the terms of the GNU GPL, version 2 or later.
7 * See the COPYING file in the top-level directory.
8 *
9 */
10
11 #include "qemu/osdep.h"
12
13 #include "hw/pci/pci.h"
14 #include "hw/pci/pci_ids.h"
15 #include "hw/pci/pci_bus.h"
16 #include "qemu/thread.h"
17 #include "hw/remote/machine.h"
18 #include "hw/remote/iohub.h"
19 #include "qemu/main-loop.h"
20
remote_iohub_init(RemoteIOHubState * iohub)21 void remote_iohub_init(RemoteIOHubState *iohub)
22 {
23 int pirq;
24
25 memset(&iohub->irqfds, 0, sizeof(iohub->irqfds));
26 memset(&iohub->resamplefds, 0, sizeof(iohub->resamplefds));
27
28 for (pirq = 0; pirq < REMOTE_IOHUB_NB_PIRQS; pirq++) {
29 qemu_mutex_init(&iohub->irq_level_lock[pirq]);
30 iohub->irq_level[pirq] = 0;
31 event_notifier_init_fd(&iohub->irqfds[pirq], -1);
32 event_notifier_init_fd(&iohub->resamplefds[pirq], -1);
33 }
34 }
35
remote_iohub_map_irq(PCIDevice * pci_dev,int intx)36 int remote_iohub_map_irq(PCIDevice *pci_dev, int intx)
37 {
38 return pci_dev->devfn;
39 }
40
remote_iohub_set_irq(void * opaque,int pirq,int level)41 void remote_iohub_set_irq(void *opaque, int pirq, int level)
42 {
43 RemoteIOHubState *iohub = opaque;
44
45 assert(pirq >= 0);
46 assert(pirq < PCI_DEVFN_MAX);
47
48 QEMU_LOCK_GUARD(&iohub->irq_level_lock[pirq]);
49
50 if (level) {
51 if (++iohub->irq_level[pirq] == 1) {
52 event_notifier_set(&iohub->irqfds[pirq]);
53 }
54 } else if (iohub->irq_level[pirq] > 0) {
55 iohub->irq_level[pirq]--;
56 }
57 }
58
intr_resample_handler(void * opaque)59 static void intr_resample_handler(void *opaque)
60 {
61 ResampleToken *token = opaque;
62 RemoteIOHubState *iohub = token->iohub;
63 int pirq, s;
64
65 pirq = token->pirq;
66
67 s = event_notifier_test_and_clear(&iohub->resamplefds[pirq]);
68
69 assert(s >= 0);
70
71 QEMU_LOCK_GUARD(&iohub->irq_level_lock[pirq]);
72
73 if (iohub->irq_level[pirq]) {
74 event_notifier_set(&iohub->irqfds[pirq]);
75 }
76 }
77
process_set_irqfd_msg(PCIDevice * pci_dev,MPQemuMsg * msg)78 void process_set_irqfd_msg(PCIDevice *pci_dev, MPQemuMsg *msg)
79 {
80 RemoteMachineState *machine = REMOTE_MACHINE(current_machine);
81 RemoteIOHubState *iohub = &machine->iohub;
82 int pirq, intx;
83
84 intx = pci_get_byte(pci_dev->config + PCI_INTERRUPT_PIN) - 1;
85
86 pirq = remote_iohub_map_irq(pci_dev, intx);
87
88 if (event_notifier_get_fd(&iohub->irqfds[pirq]) != -1) {
89 qemu_set_fd_handler(event_notifier_get_fd(&iohub->resamplefds[pirq]),
90 NULL, NULL, NULL);
91 event_notifier_cleanup(&iohub->irqfds[pirq]);
92 event_notifier_cleanup(&iohub->resamplefds[pirq]);
93 memset(&iohub->token[pirq], 0, sizeof(ResampleToken));
94 }
95
96 event_notifier_init_fd(&iohub->irqfds[pirq], msg->fds[0]);
97 event_notifier_init_fd(&iohub->resamplefds[pirq], msg->fds[1]);
98
99 iohub->token[pirq].iohub = iohub;
100 iohub->token[pirq].pirq = pirq;
101
102 qemu_set_fd_handler(msg->fds[1], intr_resample_handler, NULL,
103 &iohub->token[pirq]);
104 }
105