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_finalize(RemoteIOHubState * iohub)36 void remote_iohub_finalize(RemoteIOHubState *iohub)
37 {
38 int pirq;
39
40 for (pirq = 0; pirq < REMOTE_IOHUB_NB_PIRQS; pirq++) {
41 qemu_set_fd_handler(event_notifier_get_fd(&iohub->resamplefds[pirq]),
42 NULL, NULL, NULL);
43 event_notifier_cleanup(&iohub->irqfds[pirq]);
44 event_notifier_cleanup(&iohub->resamplefds[pirq]);
45 qemu_mutex_destroy(&iohub->irq_level_lock[pirq]);
46 }
47 }
48
remote_iohub_map_irq(PCIDevice * pci_dev,int intx)49 int remote_iohub_map_irq(PCIDevice *pci_dev, int intx)
50 {
51 return pci_dev->devfn;
52 }
53
remote_iohub_set_irq(void * opaque,int pirq,int level)54 void remote_iohub_set_irq(void *opaque, int pirq, int level)
55 {
56 RemoteIOHubState *iohub = opaque;
57
58 assert(pirq >= 0);
59 assert(pirq < PCI_DEVFN_MAX);
60
61 QEMU_LOCK_GUARD(&iohub->irq_level_lock[pirq]);
62
63 if (level) {
64 if (++iohub->irq_level[pirq] == 1) {
65 event_notifier_set(&iohub->irqfds[pirq]);
66 }
67 } else if (iohub->irq_level[pirq] > 0) {
68 iohub->irq_level[pirq]--;
69 }
70 }
71
intr_resample_handler(void * opaque)72 static void intr_resample_handler(void *opaque)
73 {
74 ResampleToken *token = opaque;
75 RemoteIOHubState *iohub = token->iohub;
76 int pirq, s;
77
78 pirq = token->pirq;
79
80 s = event_notifier_test_and_clear(&iohub->resamplefds[pirq]);
81
82 assert(s >= 0);
83
84 QEMU_LOCK_GUARD(&iohub->irq_level_lock[pirq]);
85
86 if (iohub->irq_level[pirq]) {
87 event_notifier_set(&iohub->irqfds[pirq]);
88 }
89 }
90
process_set_irqfd_msg(PCIDevice * pci_dev,MPQemuMsg * msg)91 void process_set_irqfd_msg(PCIDevice *pci_dev, MPQemuMsg *msg)
92 {
93 RemoteMachineState *machine = REMOTE_MACHINE(current_machine);
94 RemoteIOHubState *iohub = &machine->iohub;
95 int pirq, intx;
96
97 intx = pci_get_byte(pci_dev->config + PCI_INTERRUPT_PIN) - 1;
98
99 pirq = remote_iohub_map_irq(pci_dev, intx);
100
101 if (event_notifier_get_fd(&iohub->irqfds[pirq]) != -1) {
102 qemu_set_fd_handler(event_notifier_get_fd(&iohub->resamplefds[pirq]),
103 NULL, NULL, NULL);
104 event_notifier_cleanup(&iohub->irqfds[pirq]);
105 event_notifier_cleanup(&iohub->resamplefds[pirq]);
106 memset(&iohub->token[pirq], 0, sizeof(ResampleToken));
107 }
108
109 event_notifier_init_fd(&iohub->irqfds[pirq], msg->fds[0]);
110 event_notifier_init_fd(&iohub->resamplefds[pirq], msg->fds[1]);
111
112 iohub->token[pirq].iohub = iohub;
113 iohub->token[pirq].pirq = pirq;
114
115 qemu_set_fd_handler(msg->fds[1], intr_resample_handler, NULL,
116 &iohub->token[pirq]);
117 }
118