File: [cvs.NetBSD.org] / src / sys / dev / pci / virtio.c (download)
Revision 1.21, Sat Mar 25 17:50:51 2017 UTC (7 years ago) by jdolecek
Branch: MAIN
Changes since 1.20: +7 -7
lines
use ipl level specified by child when attaching interrupts, instead of always
using IPL_NET
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/* $NetBSD: virtio.c,v 1.21 2017/03/25 17:50:51 jdolecek Exp $ */
/*
* Copyright (c) 2010 Minoura Makoto.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: virtio.c,v 1.21 2017/03/25 17:50:51 jdolecek Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/atomic.h>
#include <sys/bus.h>
#include <sys/device.h>
#include <sys/kmem.h>
#include <sys/module.h>
#include <dev/pci/pcidevs.h>
#include <dev/pci/pcireg.h>
#include <dev/pci/pcivar.h>
#include <dev/pci/virtioreg.h>
#include <dev/pci/virtiovar.h>
#define MINSEG_INDIRECT 2 /* use indirect if nsegs >= this value */
static int virtio_match(device_t, cfdata_t, void *);
static void virtio_attach(device_t, device_t, void *);
static int virtio_rescan(device_t, const char *, const int *);
static int virtio_detach(device_t, int);
static int virtio_intr(void *arg);
static int virtio_msix_queue_intr(void *);
static int virtio_msix_config_intr(void *);
static int virtio_setup_msix_vectors(struct virtio_softc *);
static int virtio_setup_msix_interrupts(struct virtio_softc *,
struct pci_attach_args *);
static int virtio_setup_intx_interrupt(struct virtio_softc *,
struct pci_attach_args *);
static int virtio_setup_interrupts(struct virtio_softc *);
static void virtio_soft_intr(void *arg);
static void virtio_init_vq(struct virtio_softc *,
struct virtqueue *, const bool);
CFATTACH_DECL3_NEW(virtio, sizeof(struct virtio_softc),
virtio_match, virtio_attach, virtio_detach, NULL, virtio_rescan, NULL,
DVF_DETACH_SHUTDOWN);
/* we use the legacy virtio spec, so the pci registers are host native
* byte order, not pci (i.e. LE) byte order */
static inline uint16_t
nbo_bus_space_read_2(bus_space_tag_t space, bus_space_handle_t handle,
bus_size_t offset)
{
return le16toh(bus_space_read_2(space, handle, offset));
}
static inline uint32_t
nbo_bus_space_read_4(bus_space_tag_t space, bus_space_handle_t handle,
bus_size_t offset)
{
return le32toh(bus_space_read_4(space, handle, offset));
}
static void
nbo_bus_space_write_2(bus_space_tag_t space, bus_space_handle_t handle,
bus_size_t offset, uint16_t value)
{
bus_space_write_2(space, handle, offset, htole16(value));
}
static void
nbo_bus_space_write_4(bus_space_tag_t space, bus_space_handle_t handle,
bus_size_t offset, uint16_t value)
{
bus_space_write_4(space, handle, offset, htole32(value));
}
/* some functions access registers at 4 byte offset for little/high halves */
#if BYTE_ORDER == BIG_ENDIAN
#define REG_HI_OFF 0
#define REG_LO_OFF 4
#else
#define REG_HI_OFF 4
#define REG_LO_OFF 0
#endif
static void
virtio_set_status(struct virtio_softc *sc, int status)
{
int old = 0;
if (status != 0)
old = bus_space_read_1(sc->sc_iot, sc->sc_ioh,
VIRTIO_CONFIG_DEVICE_STATUS);
bus_space_write_1(sc->sc_iot, sc->sc_ioh, VIRTIO_CONFIG_DEVICE_STATUS,
status|old);
}
#define virtio_device_reset(sc) virtio_set_status((sc), 0)
static int
virtio_match(device_t parent, cfdata_t match, void *aux)
{
struct pci_attach_args *pa;
pa = (struct pci_attach_args *)aux;
switch (PCI_VENDOR(pa->pa_id)) {
case PCI_VENDOR_QUMRANET:
if ((PCI_PRODUCT_QUMRANET_VIRTIO_1000 <=
PCI_PRODUCT(pa->pa_id)) &&
(PCI_PRODUCT(pa->pa_id) <=
PCI_PRODUCT_QUMRANET_VIRTIO_103F))
return 1;
break;
}
return 0;
}
static const char *virtio_device_name[] = {
"Unknown (0)", /* 0 */
"Network", /* 1 */
"Block", /* 2 */
"Console", /* 3 */
"Entropy", /* 4 */
"Memory Balloon", /* 5 */
"I/O Memory", /* 6 */
"Remote Processor Messaging", /* 7 */
"SCSI", /* 8 */
"9P Transport", /* 9 */
"mac80211 wlan", /* 10 */
};
#define NDEVNAMES __arraycount(virtio_device_name)
#define VIRTIO_MSIX_CONFIG_VECTOR_INDEX 0
#define VIRTIO_MSIX_QUEUE_VECTOR_INDEX 1
static int
virtio_setup_msix_vectors(struct virtio_softc *sc)
{
int offset, vector, ret, qid;
offset = VIRTIO_CONFIG_MSI_CONFIG_VECTOR;
vector = VIRTIO_MSIX_CONFIG_VECTOR_INDEX;
nbo_bus_space_write_2(sc->sc_iot, sc->sc_ioh, offset, vector);
ret = nbo_bus_space_read_2(sc->sc_iot, sc->sc_ioh, offset);
aprint_debug_dev(sc->sc_dev, "expected=%d, actual=%d\n",
vector, ret);
if (ret != vector)
return -1;
for (qid = 0; qid < sc->sc_nvqs; qid++) {
offset = VIRTIO_CONFIG_QUEUE_SELECT;
nbo_bus_space_write_2(sc->sc_iot, sc->sc_ioh, offset, qid);
offset = VIRTIO_CONFIG_MSI_QUEUE_VECTOR;
vector = VIRTIO_MSIX_QUEUE_VECTOR_INDEX;
nbo_bus_space_write_2(sc->sc_iot, sc->sc_ioh, offset, vector);
ret = nbo_bus_space_read_2(sc->sc_iot, sc->sc_ioh, offset);
aprint_debug_dev(sc->sc_dev, "expected=%d, actual=%d\n",
vector, ret);
if (ret != vector)
return -1;
}
return 0;
}
static int
virtio_setup_msix_interrupts(struct virtio_softc *sc,
struct pci_attach_args *pa)
{
device_t self = sc->sc_dev;
pci_chipset_tag_t pc = pa->pa_pc;
char intrbuf[PCI_INTRSTR_LEN];
char const *intrstr;
int idx;
idx = VIRTIO_MSIX_CONFIG_VECTOR_INDEX;
if (sc->sc_flags & VIRTIO_F_PCI_INTR_MPSAFE)
pci_intr_setattr(pc, &sc->sc_ihp[idx], PCI_INTR_MPSAFE, true);
sc->sc_ihs[idx] = pci_intr_establish_xname(pc, sc->sc_ihp[idx],
sc->sc_ipl, virtio_msix_config_intr, sc, device_xname(sc->sc_dev));
if (sc->sc_ihs[idx] == NULL) {
aprint_error_dev(self, "couldn't establish MSI-X for config\n");
goto error;
}
idx = VIRTIO_MSIX_QUEUE_VECTOR_INDEX;
if (sc->sc_flags & VIRTIO_F_PCI_INTR_MPSAFE)
pci_intr_setattr(pc, &sc->sc_ihp[idx], PCI_INTR_MPSAFE, true);
sc->sc_ihs[idx] = pci_intr_establish_xname(pc, sc->sc_ihp[idx],
sc->sc_ipl, virtio_msix_queue_intr, sc, device_xname(sc->sc_dev));
if (sc->sc_ihs[idx] == NULL) {
aprint_error_dev(self, "couldn't establish MSI-X for queues\n");
goto error;
}
if (virtio_setup_msix_vectors(sc) != 0) {
aprint_error_dev(self, "couldn't setup MSI-X vectors\n");
goto error;
}
idx = VIRTIO_MSIX_CONFIG_VECTOR_INDEX;
intrstr = pci_intr_string(pc, sc->sc_ihp[idx], intrbuf, sizeof(intrbuf));
aprint_normal_dev(self, "config interrupting at %s\n", intrstr);
idx = VIRTIO_MSIX_QUEUE_VECTOR_INDEX;
intrstr = pci_intr_string(pc, sc->sc_ihp[idx], intrbuf, sizeof(intrbuf));
aprint_normal_dev(self, "queues interrupting at %s\n", intrstr);
return 0;
error:
idx = VIRTIO_MSIX_CONFIG_VECTOR_INDEX;
if (sc->sc_ihs[idx] != NULL)
pci_intr_disestablish(sc->sc_pc, sc->sc_ihs[idx]);
idx = VIRTIO_MSIX_QUEUE_VECTOR_INDEX;
if (sc->sc_ihs[idx] != NULL)
pci_intr_disestablish(sc->sc_pc, sc->sc_ihs[idx]);
return -1;
}
static int
virtio_setup_intx_interrupt(struct virtio_softc *sc,
struct pci_attach_args *pa)
{
device_t self = sc->sc_dev;
pci_chipset_tag_t pc = pa->pa_pc;
char intrbuf[PCI_INTRSTR_LEN];
char const *intrstr;
if (sc->sc_flags & VIRTIO_F_PCI_INTR_MPSAFE)
pci_intr_setattr(pc, &sc->sc_ihp[0], PCI_INTR_MPSAFE, true);
sc->sc_ihs[0] = pci_intr_establish_xname(pc, sc->sc_ihp[0],
sc->sc_ipl, virtio_intr, sc, device_xname(sc->sc_dev));
if (sc->sc_ihs[0] == NULL) {
aprint_error_dev(self, "couldn't establish INTx\n");
return -1;
}
intrstr = pci_intr_string(pc, sc->sc_ihp[0], intrbuf, sizeof(intrbuf));
aprint_normal_dev(self, "interrupting at %s\n", intrstr);
return 0;
}
static int
virtio_setup_interrupts(struct virtio_softc *sc)
{
device_t self = sc->sc_dev;
pci_chipset_tag_t pc = sc->sc_pa.pa_pc;
int error;
int nmsix;
int counts[PCI_INTR_TYPE_SIZE];
pci_intr_type_t max_type;
nmsix = pci_msix_count(sc->sc_pa.pa_pc, sc->sc_pa.pa_tag);
aprint_debug_dev(self, "pci_msix_count=%d\n", nmsix);
/* We need at least two: one for config and the other for queues */
if ((sc->sc_flags & VIRTIO_F_PCI_INTR_MSIX) == 0 || nmsix < 2) {
/* Try INTx only */
max_type = PCI_INTR_TYPE_INTX;
counts[PCI_INTR_TYPE_INTX] = 1;
} else {
/* Try MSI-X first and INTx second */
max_type = PCI_INTR_TYPE_MSIX;
counts[PCI_INTR_TYPE_MSIX] = 2;
counts[PCI_INTR_TYPE_MSI] = 0;
counts[PCI_INTR_TYPE_INTX] = 1;
}
retry:
error = pci_intr_alloc(&sc->sc_pa, &sc->sc_ihp, counts, max_type);
if (error != 0) {
aprint_error_dev(self, "couldn't map interrupt\n");
return -1;
}
if (pci_intr_type(pc, sc->sc_ihp[0]) == PCI_INTR_TYPE_MSIX) {
sc->sc_ihs = kmem_alloc(sizeof(*sc->sc_ihs) * 2,
KM_SLEEP);
if (sc->sc_ihs == NULL) {
pci_intr_release(pc, sc->sc_ihp, 2);
/* Retry INTx */
max_type = PCI_INTR_TYPE_INTX;
counts[PCI_INTR_TYPE_INTX] = 1;
goto retry;
}
error = virtio_setup_msix_interrupts(sc, &sc->sc_pa);
if (error != 0) {
kmem_free(sc->sc_ihs, sizeof(*sc->sc_ihs) * 2);
pci_intr_release(pc, sc->sc_ihp, 2);
/* Retry INTx */
max_type = PCI_INTR_TYPE_INTX;
counts[PCI_INTR_TYPE_INTX] = 1;
goto retry;
}
sc->sc_ihs_num = 2;
sc->sc_config_offset = VIRTIO_CONFIG_DEVICE_CONFIG_MSI;
} else if (pci_intr_type(pc, sc->sc_ihp[0]) == PCI_INTR_TYPE_INTX) {
sc->sc_ihs = kmem_alloc(sizeof(*sc->sc_ihs) * 1,
KM_SLEEP);
if (sc->sc_ihs == NULL) {
pci_intr_release(pc, sc->sc_ihp, 1);
return -1;
}
error = virtio_setup_intx_interrupt(sc, &sc->sc_pa);
if (error != 0) {
kmem_free(sc->sc_ihs, sizeof(*sc->sc_ihs) * 1);
pci_intr_release(pc, sc->sc_ihp, 1);
return -1;
}
sc->sc_ihs_num = 1;
sc->sc_config_offset = VIRTIO_CONFIG_DEVICE_CONFIG_NOMSI;
}
return 0;
}
static void
virtio_attach(device_t parent, device_t self, void *aux)
{
struct virtio_softc *sc = device_private(self);
struct pci_attach_args *pa = (struct pci_attach_args *)aux;
pci_chipset_tag_t pc = pa->pa_pc;
pcitag_t tag = pa->pa_tag;
int revision;
pcireg_t id;
revision = PCI_REVISION(pa->pa_class);
if (revision != 0) {
aprint_normal(": unknown revision 0x%02x; giving up\n",
revision);
return;
}
aprint_normal("\n");
aprint_naive("\n");
/* subsystem ID shows what I am */
id = pci_conf_read(pc, tag, PCI_SUBSYS_ID_REG);
aprint_normal_dev(self, "Virtio %s Device (rev. 0x%02x)\n",
(PCI_SUBSYS_ID(id) < NDEVNAMES?
virtio_device_name[PCI_SUBSYS_ID(id)] : "Unknown"),
revision);
sc->sc_dev = self;
sc->sc_pc = pc;
sc->sc_tag = tag;
sc->sc_iot = pa->pa_iot;
if (pci_dma64_available(pa))
sc->sc_dmat = pa->pa_dmat64;
else
sc->sc_dmat = pa->pa_dmat;
sc->sc_config_offset = VIRTIO_CONFIG_DEVICE_CONFIG_NOMSI;
if (pci_mapreg_map(pa, PCI_MAPREG_START, PCI_MAPREG_TYPE_IO, 0,
&sc->sc_iot, &sc->sc_ioh, NULL, &sc->sc_iosize)) {
aprint_error_dev(self, "can't map i/o space\n");
return;
}
virtio_device_reset(sc);
virtio_set_status(sc, VIRTIO_CONFIG_DEVICE_STATUS_ACK);
virtio_set_status(sc, VIRTIO_CONFIG_DEVICE_STATUS_DRIVER);
/* XXX: use softc as aux... */
sc->sc_childdevid = PCI_SUBSYS_ID(id);
sc->sc_child = NULL;
sc->sc_pa = *pa;
virtio_rescan(self, "virtio", 0);
return;
}
/* ARGSUSED */
static int
virtio_rescan(device_t self, const char *attr, const int *scan_flags)
{
struct virtio_softc *sc;
int r;
sc = device_private(self);
if (sc->sc_child) /* Child already attached? */
return 0;
config_found_ia(self, attr, sc, NULL);
if (sc->sc_child == NULL) {
aprint_error_dev(self,
"no matching child driver; not configured\n");
return 0;
}
if (sc->sc_child == (void*)1) { /* this shows error */
aprint_error_dev(self,
"virtio configuration failed\n");
virtio_set_status(sc, VIRTIO_CONFIG_DEVICE_STATUS_FAILED);
return 0;
}
r = virtio_setup_interrupts(sc);
if (r != 0) {
aprint_error_dev(self, "failed to setup interrupts\n");
virtio_set_status(sc, VIRTIO_CONFIG_DEVICE_STATUS_FAILED);
return 0;
}
sc->sc_soft_ih = NULL;
if (sc->sc_flags & VIRTIO_F_PCI_INTR_SOFTINT) {
u_int flags = SOFTINT_NET;
if (sc->sc_flags & VIRTIO_F_PCI_INTR_MPSAFE)
flags |= SOFTINT_MPSAFE;
sc->sc_soft_ih = softint_establish(flags, virtio_soft_intr, sc);
if (sc->sc_soft_ih == NULL)
aprint_error(": failed to establish soft interrupt\n");
}
virtio_set_status(sc, VIRTIO_CONFIG_DEVICE_STATUS_DRIVER_OK);
return 0;
}
static int
virtio_detach(device_t self, int flags)
{
struct virtio_softc *sc = device_private(self);
int r;
int i;
if (sc->sc_child != 0 && sc->sc_child != (void*)1) {
r = config_detach(sc->sc_child, flags);
if (r)
return r;
}
KASSERT(sc->sc_child == 0 || sc->sc_child == (void*)1);
KASSERT(sc->sc_vqs == 0);
for (i = 0; i < sc->sc_ihs_num; i++) {
if (sc->sc_ihs[i] == NULL)
continue;
pci_intr_disestablish(sc->sc_pc, sc->sc_ihs[i]);
}
pci_intr_release(sc->sc_pc, sc->sc_ihp, sc->sc_ihs_num);
if (sc->sc_ihs != NULL)
kmem_free(sc->sc_ihs, sizeof(*sc->sc_ihs) * sc->sc_ihs_num);
sc->sc_ihs_num = 0;
if (sc->sc_iosize)
bus_space_unmap(sc->sc_iot, sc->sc_ioh, sc->sc_iosize);
sc->sc_iosize = 0;
return 0;
}
/*
* Reset the device.
*/
/*
* To reset the device to a known state, do following:
* virtio_reset(sc); // this will stop the device activity
* <dequeue finished requests>; // virtio_dequeue() still can be called
* <revoke pending requests in the vqs if any>;
* virtio_reinit_begin(sc); // dequeue prohibitted
* newfeatures = virtio_negotiate_features(sc, requestedfeatures);
* <some other initialization>;
* virtio_reinit_end(sc); // device activated; enqueue allowed
* Once attached, feature negotiation can only be allowed after virtio_reset.
*/
void
virtio_reset(struct virtio_softc *sc)
{
virtio_device_reset(sc);
}
void
virtio_reinit_start(struct virtio_softc *sc)
{
int i;
virtio_set_status(sc, VIRTIO_CONFIG_DEVICE_STATUS_ACK);
virtio_set_status(sc, VIRTIO_CONFIG_DEVICE_STATUS_DRIVER);
for (i = 0; i < sc->sc_nvqs; i++) {
int n;
struct virtqueue *vq = &sc->sc_vqs[i];
nbo_bus_space_write_2(sc->sc_iot, sc->sc_ioh,
VIRTIO_CONFIG_QUEUE_SELECT,
vq->vq_index);
n = nbo_bus_space_read_2(sc->sc_iot, sc->sc_ioh,
VIRTIO_CONFIG_QUEUE_SIZE);
if (n == 0) /* vq disappeared */
continue;
if (n != vq->vq_num) {
panic("%s: virtqueue size changed, vq index %d\n",
device_xname(sc->sc_dev),
vq->vq_index);
}
virtio_init_vq(sc, vq, true);
nbo_bus_space_write_4(sc->sc_iot, sc->sc_ioh,
VIRTIO_CONFIG_QUEUE_ADDRESS,
(vq->vq_dmamap->dm_segs[0].ds_addr
/ VIRTIO_PAGE_SIZE));
}
/* MSI-X should have more than one handles where INTx has just one */
if (sc->sc_ihs_num > 1) {
if (virtio_setup_msix_vectors(sc) != 0) {
aprint_error_dev(sc->sc_dev,
"couldn't setup MSI-X vectors\n");
return;
}
}
}
void
virtio_reinit_end(struct virtio_softc *sc)
{
virtio_set_status(sc, VIRTIO_CONFIG_DEVICE_STATUS_DRIVER_OK);
}
/*
* Feature negotiation.
*/
uint32_t
virtio_negotiate_features(struct virtio_softc *sc, uint32_t guest_features)
{
uint32_t r;
if (!(device_cfdata(sc->sc_dev)->cf_flags & 1) &&
!(device_cfdata(sc->sc_child)->cf_flags & 1)) /* XXX */
guest_features |= VIRTIO_F_RING_INDIRECT_DESC;
r = nbo_bus_space_read_4(sc->sc_iot, sc->sc_ioh,
VIRTIO_CONFIG_DEVICE_FEATURES);
r &= guest_features;
nbo_bus_space_write_4(sc->sc_iot, sc->sc_ioh,
VIRTIO_CONFIG_GUEST_FEATURES, r);
sc->sc_features = r;
if (r & VIRTIO_F_RING_INDIRECT_DESC)
sc->sc_indirect = true;
else
sc->sc_indirect = false;
return r;
}
/*
* Device configuration registers.
*/
uint8_t
virtio_read_device_config_1(struct virtio_softc *sc, int index)
{
return bus_space_read_1(sc->sc_iot, sc->sc_ioh,
sc->sc_config_offset + index);
}
uint16_t
virtio_read_device_config_2(struct virtio_softc *sc, int index)
{
return nbo_bus_space_read_2(sc->sc_iot, sc->sc_ioh,
sc->sc_config_offset + index);
}
uint32_t
virtio_read_device_config_4(struct virtio_softc *sc, int index)
{
return nbo_bus_space_read_4(sc->sc_iot, sc->sc_ioh,
sc->sc_config_offset + index);
}
uint64_t
virtio_read_device_config_8(struct virtio_softc *sc, int index)
{
uint64_t r;
r = nbo_bus_space_read_4(sc->sc_iot, sc->sc_ioh,
sc->sc_config_offset + index + REG_HI_OFF);
r <<= 32;
r |= nbo_bus_space_read_4(sc->sc_iot, sc->sc_ioh,
sc->sc_config_offset + index + REG_LO_OFF);
return r;
}
void
virtio_write_device_config_1(struct virtio_softc *sc,
int index, uint8_t value)
{
bus_space_write_1(sc->sc_iot, sc->sc_ioh,
sc->sc_config_offset + index, value);
}
void
virtio_write_device_config_2(struct virtio_softc *sc,
int index, uint16_t value)
{
nbo_bus_space_write_2(sc->sc_iot, sc->sc_ioh,
sc->sc_config_offset + index, value);
}
void
virtio_write_device_config_4(struct virtio_softc *sc,
int index, uint32_t value)
{
nbo_bus_space_write_4(sc->sc_iot, sc->sc_ioh,
sc->sc_config_offset + index, value);
}
void
virtio_write_device_config_8(struct virtio_softc *sc,
int index, uint64_t value)
{
nbo_bus_space_write_4(sc->sc_iot, sc->sc_ioh,
sc->sc_config_offset + index + REG_LO_OFF,
value & 0xffffffff);
nbo_bus_space_write_4(sc->sc_iot, sc->sc_ioh,
sc->sc_config_offset + index + REG_HI_OFF,
value >> 32);
}
/*
* Interrupt handler.
*/
static int
virtio_intr(void *arg)
{
struct virtio_softc *sc = arg;
int isr, r = 0;
/* check and ack the interrupt */
isr = bus_space_read_1(sc->sc_iot, sc->sc_ioh,
VIRTIO_CONFIG_ISR_STATUS);
if (isr == 0)
return 0;
if ((isr & VIRTIO_CONFIG_ISR_CONFIG_CHANGE) &&
(sc->sc_config_change != NULL))
r = (sc->sc_config_change)(sc);
if (sc->sc_intrhand != NULL) {
if (sc->sc_soft_ih != NULL)
softint_schedule(sc->sc_soft_ih);
else
r |= (sc->sc_intrhand)(sc);
}
return r;
}
static int
virtio_msix_queue_intr(void *arg)
{
struct virtio_softc *sc = arg;
int r = 0;
if (sc->sc_intrhand != NULL) {
if (sc->sc_soft_ih != NULL)
softint_schedule(sc->sc_soft_ih);
else
r |= (sc->sc_intrhand)(sc);
}
return r;
}
static int
virtio_msix_config_intr(void *arg)
{
struct virtio_softc *sc = arg;
/* TODO: handle events */
aprint_debug_dev(sc->sc_dev, "%s\n", __func__);
return 1;
}
static void
virtio_soft_intr(void *arg)
{
struct virtio_softc *sc = arg;
KASSERT(sc->sc_intrhand != NULL);
(sc->sc_intrhand)(sc);
}
/*
* dmamap sync operations for a virtqueue.
*/
static inline void
vq_sync_descs(struct virtio_softc *sc, struct virtqueue *vq, int ops)
{
/* availoffset == sizeof(vring_desc)*vq_num */
bus_dmamap_sync(sc->sc_dmat, vq->vq_dmamap, 0, vq->vq_availoffset,
ops);
}
static inline void
vq_sync_aring(struct virtio_softc *sc, struct virtqueue *vq, int ops)
{
bus_dmamap_sync(sc->sc_dmat, vq->vq_dmamap,
vq->vq_availoffset,
offsetof(struct vring_avail, ring)
+ vq->vq_num * sizeof(uint16_t),
ops);
}
static inline void
vq_sync_uring(struct virtio_softc *sc, struct virtqueue *vq, int ops)
{
bus_dmamap_sync(sc->sc_dmat, vq->vq_dmamap,
vq->vq_usedoffset,
offsetof(struct vring_used, ring)
+ vq->vq_num * sizeof(struct vring_used_elem),
ops);
}
static inline void
vq_sync_indirect(struct virtio_softc *sc, struct virtqueue *vq, int slot,
int ops)
{
int offset = vq->vq_indirectoffset
+ sizeof(struct vring_desc) * vq->vq_maxnsegs * slot;
bus_dmamap_sync(sc->sc_dmat, vq->vq_dmamap,
offset, sizeof(struct vring_desc) * vq->vq_maxnsegs,
ops);
}
/*
* Can be used as sc_intrhand.
*/
/*
* Scan vq, bus_dmamap_sync for the vqs (not for the payload),
* and calls (*vq_done)() if some entries are consumed.
*/
int
virtio_vq_intr(struct virtio_softc *sc)
{
struct virtqueue *vq;
int i, r = 0;
for (i = 0; i < sc->sc_nvqs; i++) {
vq = &sc->sc_vqs[i];
if (vq->vq_queued) {
vq->vq_queued = 0;
vq_sync_aring(sc, vq, BUS_DMASYNC_POSTWRITE);
}
vq_sync_uring(sc, vq, BUS_DMASYNC_POSTREAD);
membar_consumer();
if (vq->vq_used_idx != vq->vq_used->idx) {
if (vq->vq_done)
r |= (vq->vq_done)(vq);
}
}
return r;
}
/*
* Start/stop vq interrupt. No guarantee.
*/
void
virtio_stop_vq_intr(struct virtio_softc *sc, struct virtqueue *vq)
{
vq->vq_avail->flags |= VRING_AVAIL_F_NO_INTERRUPT;
vq_sync_aring(sc, vq, BUS_DMASYNC_PREWRITE);
vq->vq_queued++;
}
void
virtio_start_vq_intr(struct virtio_softc *sc, struct virtqueue *vq)
{
vq->vq_avail->flags &= ~VRING_AVAIL_F_NO_INTERRUPT;
vq_sync_aring(sc, vq, BUS_DMASYNC_PREWRITE);
vq->vq_queued++;
}
/*
* Initialize vq structure.
*/
static void
virtio_init_vq(struct virtio_softc *sc, struct virtqueue *vq,
const bool reinit)
{
int i, j;
int vq_size = vq->vq_num;
memset(vq->vq_vaddr, 0, vq->vq_bytesize);
/* build the indirect descriptor chain */
if (vq->vq_indirect != NULL) {
struct vring_desc *vd;
for (i = 0; i < vq_size; i++) {
vd = vq->vq_indirect;
vd += vq->vq_maxnsegs * i;
for (j = 0; j < vq->vq_maxnsegs-1; j++)
vd[j].next = j + 1;
}
}
/* free slot management */
SIMPLEQ_INIT(&vq->vq_freelist);
for (i = 0; i < vq_size; i++) {
SIMPLEQ_INSERT_TAIL(&vq->vq_freelist,
&vq->vq_entries[i], qe_list);
vq->vq_entries[i].qe_index = i;
}
if (!reinit)
mutex_init(&vq->vq_freelist_lock, MUTEX_SPIN, sc->sc_ipl);
/* enqueue/dequeue status */
vq->vq_avail_idx = 0;
vq->vq_used_idx = 0;
vq->vq_queued = 0;
if (!reinit) {
mutex_init(&vq->vq_aring_lock, MUTEX_SPIN, sc->sc_ipl);
mutex_init(&vq->vq_uring_lock, MUTEX_SPIN, sc->sc_ipl);
}
vq_sync_aring(sc, vq, BUS_DMASYNC_PREWRITE);
vq_sync_uring(sc, vq, BUS_DMASYNC_PREREAD);
vq->vq_queued++;
}
/*
* Allocate/free a vq.
*/
int
virtio_alloc_vq(struct virtio_softc *sc, struct virtqueue *vq, int index,
int maxsegsize, int maxnsegs, const char *name)
{
int vq_size, allocsize1, allocsize2, allocsize3, allocsize = 0;
int rsegs, r;
#define VIRTQUEUE_ALIGN(n) (((n)+(VIRTIO_PAGE_SIZE-1))& \
~(VIRTIO_PAGE_SIZE-1))
memset(vq, 0, sizeof(*vq));
nbo_bus_space_write_2(sc->sc_iot, sc->sc_ioh,
VIRTIO_CONFIG_QUEUE_SELECT, index);
vq_size = nbo_bus_space_read_2(sc->sc_iot, sc->sc_ioh,
VIRTIO_CONFIG_QUEUE_SIZE);
if (vq_size == 0) {
aprint_error_dev(sc->sc_dev,
"virtqueue not exist, index %d for %s\n",
index, name);
goto err;
}
/* allocsize1: descriptor table + avail ring + pad */
allocsize1 = VIRTQUEUE_ALIGN(sizeof(struct vring_desc)*vq_size
+ sizeof(uint16_t)*(2+vq_size));
/* allocsize2: used ring + pad */
allocsize2 = VIRTQUEUE_ALIGN(sizeof(uint16_t)*2
+ sizeof(struct vring_used_elem)*vq_size);
/* allocsize3: indirect table */
if (sc->sc_indirect && maxnsegs >= MINSEG_INDIRECT)
allocsize3 = sizeof(struct vring_desc) * maxnsegs * vq_size;
else
allocsize3 = 0;
allocsize = allocsize1 + allocsize2 + allocsize3;
/* alloc and map the memory */
r = bus_dmamem_alloc(sc->sc_dmat, allocsize, VIRTIO_PAGE_SIZE, 0,
&vq->vq_segs[0], 1, &rsegs, BUS_DMA_NOWAIT);
if (r != 0) {
aprint_error_dev(sc->sc_dev,
"virtqueue %d for %s allocation failed, "
"error code %d\n", index, name, r);
goto err;
}
r = bus_dmamem_map(sc->sc_dmat, &vq->vq_segs[0], 1, allocsize,
&vq->vq_vaddr, BUS_DMA_NOWAIT);
if (r != 0) {
aprint_error_dev(sc->sc_dev,
"virtqueue %d for %s map failed, "
"error code %d\n", index, name, r);
goto err;
}
r = bus_dmamap_create(sc->sc_dmat, allocsize, 1, allocsize, 0,
BUS_DMA_NOWAIT, &vq->vq_dmamap);
if (r != 0) {
aprint_error_dev(sc->sc_dev,
"virtqueue %d for %s dmamap creation failed, "
"error code %d\n", index, name, r);
goto err;
}
r = bus_dmamap_load(sc->sc_dmat, vq->vq_dmamap,
vq->vq_vaddr, allocsize, NULL, BUS_DMA_NOWAIT);
if (r != 0) {
aprint_error_dev(sc->sc_dev,
"virtqueue %d for %s dmamap load failed, "
"error code %d\n", index, name, r);
goto err;
}
/* set the vq address */
nbo_bus_space_write_4(sc->sc_iot, sc->sc_ioh,
VIRTIO_CONFIG_QUEUE_ADDRESS,
(vq->vq_dmamap->dm_segs[0].ds_addr
/ VIRTIO_PAGE_SIZE));
/* remember addresses and offsets for later use */
vq->vq_owner = sc;
vq->vq_num = vq_size;
vq->vq_index = index;
vq->vq_desc = vq->vq_vaddr;
vq->vq_availoffset = sizeof(struct vring_desc)*vq_size;
vq->vq_avail = (void*)(((char*)vq->vq_desc) + vq->vq_availoffset);
vq->vq_usedoffset = allocsize1;
vq->vq_used = (void*)(((char*)vq->vq_desc) + vq->vq_usedoffset);
if (allocsize3 > 0) {
vq->vq_indirectoffset = allocsize1 + allocsize2;
vq->vq_indirect = (void*)(((char*)vq->vq_desc)
+ vq->vq_indirectoffset);
}
vq->vq_bytesize = allocsize;
vq->vq_maxsegsize = maxsegsize;
vq->vq_maxnsegs = maxnsegs;
/* free slot management */
vq->vq_entries = kmem_zalloc(sizeof(struct vq_entry)*vq_size,
KM_NOSLEEP);
if (vq->vq_entries == NULL) {
r = ENOMEM;
goto err;
}
virtio_init_vq(sc, vq, false);
aprint_verbose_dev(sc->sc_dev,
"allocated %u byte for virtqueue %d for %s, "
"size %d\n", allocsize, index, name, vq_size);
if (allocsize3 > 0)
aprint_verbose_dev(sc->sc_dev,
"using %d byte (%d entries) "
"indirect descriptors\n",
allocsize3, maxnsegs * vq_size);
return 0;
err:
nbo_bus_space_write_4(sc->sc_iot, sc->sc_ioh,
VIRTIO_CONFIG_QUEUE_ADDRESS, 0);
if (vq->vq_dmamap)
bus_dmamap_destroy(sc->sc_dmat, vq->vq_dmamap);
if (vq->vq_vaddr)
bus_dmamem_unmap(sc->sc_dmat, vq->vq_vaddr, allocsize);
if (vq->vq_segs[0].ds_addr)
bus_dmamem_free(sc->sc_dmat, &vq->vq_segs[0], 1);
memset(vq, 0, sizeof(*vq));
return -1;
}
int
virtio_free_vq(struct virtio_softc *sc, struct virtqueue *vq)
{
struct vq_entry *qe;
int i = 0;
/* device must be already deactivated */
/* confirm the vq is empty */
SIMPLEQ_FOREACH(qe, &vq->vq_freelist, qe_list) {
i++;
}
if (i != vq->vq_num) {
printf("%s: freeing non-empty vq, index %d\n",
device_xname(sc->sc_dev), vq->vq_index);
return EBUSY;
}
/* tell device that there's no virtqueue any longer */
nbo_bus_space_write_2(sc->sc_iot, sc->sc_ioh,
VIRTIO_CONFIG_QUEUE_SELECT, vq->vq_index);
nbo_bus_space_write_4(sc->sc_iot, sc->sc_ioh,
VIRTIO_CONFIG_QUEUE_ADDRESS, 0);
kmem_free(vq->vq_entries, sizeof(*vq->vq_entries) * vq->vq_num);
bus_dmamap_unload(sc->sc_dmat, vq->vq_dmamap);
bus_dmamap_destroy(sc->sc_dmat, vq->vq_dmamap);
bus_dmamem_unmap(sc->sc_dmat, vq->vq_vaddr, vq->vq_bytesize);
bus_dmamem_free(sc->sc_dmat, &vq->vq_segs[0], 1);
mutex_destroy(&vq->vq_freelist_lock);
mutex_destroy(&vq->vq_uring_lock);
mutex_destroy(&vq->vq_aring_lock);
memset(vq, 0, sizeof(*vq));
return 0;
}
/*
* Free descriptor management.
*/
static struct vq_entry *
vq_alloc_entry(struct virtqueue *vq)
{
struct vq_entry *qe;
mutex_enter(&vq->vq_freelist_lock);
if (SIMPLEQ_EMPTY(&vq->vq_freelist)) {
mutex_exit(&vq->vq_freelist_lock);
return NULL;
}
qe = SIMPLEQ_FIRST(&vq->vq_freelist);
SIMPLEQ_REMOVE_HEAD(&vq->vq_freelist, qe_list);
mutex_exit(&vq->vq_freelist_lock);
return qe;
}
static void
vq_free_entry(struct virtqueue *vq, struct vq_entry *qe)
{
mutex_enter(&vq->vq_freelist_lock);
SIMPLEQ_INSERT_TAIL(&vq->vq_freelist, qe, qe_list);
mutex_exit(&vq->vq_freelist_lock);
return;
}
/*
* Enqueue several dmamaps as a single request.
*/
/*
* Typical usage:
* <queue size> number of followings are stored in arrays
* - command blocks (in dmamem) should be pre-allocated and mapped
* - dmamaps for command blocks should be pre-allocated and loaded
* - dmamaps for payload should be pre-allocated
* r = virtio_enqueue_prep(sc, vq, &slot); // allocate a slot
* if (r) // currently 0 or EAGAIN
* return r;
* r = bus_dmamap_load(dmat, dmamap_payload[slot], data, count, ..);
* if (r) {
* virtio_enqueue_abort(sc, vq, slot);
* return r;
* }
* r = virtio_enqueue_reserve(sc, vq, slot,
* dmamap_payload[slot]->dm_nsegs+1);
* // ^ +1 for command
* if (r) { // currently 0 or EAGAIN
* bus_dmamap_unload(dmat, dmamap_payload[slot]);
* return r; // do not call abort()
* }
* <setup and prepare commands>
* bus_dmamap_sync(dmat, dmamap_cmd[slot],... BUS_DMASYNC_PREWRITE);
* bus_dmamap_sync(dmat, dmamap_payload[slot],...);
* virtio_enqueue(sc, vq, slot, dmamap_cmd[slot], false);
* virtio_enqueue(sc, vq, slot, dmamap_payload[slot], iswrite);
* virtio_enqueue_commit(sc, vq, slot, true);
*/
/*
* enqueue_prep: allocate a slot number
*/
int
virtio_enqueue_prep(struct virtio_softc *sc, struct virtqueue *vq, int *slotp)
{
struct vq_entry *qe1;
KASSERT(slotp != NULL);
qe1 = vq_alloc_entry(vq);
if (qe1 == NULL)
return EAGAIN;
/* next slot is not allocated yet */
qe1->qe_next = -1;
*slotp = qe1->qe_index;
return 0;
}
/*
* enqueue_reserve: allocate remaining slots and build the descriptor chain.
*/
int
virtio_enqueue_reserve(struct virtio_softc *sc, struct virtqueue *vq,
int slot, int nsegs)
{
int indirect;
struct vq_entry *qe1 = &vq->vq_entries[slot];
KASSERT(qe1->qe_next == -1);
KASSERT(1 <= nsegs && nsegs <= vq->vq_num);
if ((vq->vq_indirect != NULL) &&
(nsegs >= MINSEG_INDIRECT) &&
(nsegs <= vq->vq_maxnsegs))
indirect = 1;
else
indirect = 0;
qe1->qe_indirect = indirect;
if (indirect) {
struct vring_desc *vd;
int i;
vd = &vq->vq_desc[qe1->qe_index];
vd->addr = vq->vq_dmamap->dm_segs[0].ds_addr
+ vq->vq_indirectoffset;
vd->addr += sizeof(struct vring_desc)
* vq->vq_maxnsegs * qe1->qe_index;
vd->len = sizeof(struct vring_desc) * nsegs;
vd->flags = VRING_DESC_F_INDIRECT;
vd = vq->vq_indirect;
vd += vq->vq_maxnsegs * qe1->qe_index;
qe1->qe_desc_base = vd;
for (i = 0; i < nsegs-1; i++) {
vd[i].flags = VRING_DESC_F_NEXT;
}
vd[i].flags = 0;
qe1->qe_next = 0;
return 0;
} else {
struct vring_desc *vd;
struct vq_entry *qe;
int i, s;
vd = &vq->vq_desc[0];
qe1->qe_desc_base = vd;
qe1->qe_next = qe1->qe_index;
s = slot;
for (i = 0; i < nsegs - 1; i++) {
qe = vq_alloc_entry(vq);
if (qe == NULL) {
vd[s].flags = 0;
virtio_enqueue_abort(sc, vq, slot);
return EAGAIN;
}
vd[s].flags = VRING_DESC_F_NEXT;
vd[s].next = qe->qe_index;
s = qe->qe_index;
}
vd[s].flags = 0;
return 0;
}
}
/*
* enqueue: enqueue a single dmamap.
*/
int
virtio_enqueue(struct virtio_softc *sc, struct virtqueue *vq, int slot,
bus_dmamap_t dmamap, bool write)
{
struct vq_entry *qe1 = &vq->vq_entries[slot];
struct vring_desc *vd = qe1->qe_desc_base;
int i;
int s = qe1->qe_next;
KASSERT(s >= 0);
KASSERT(dmamap->dm_nsegs > 0);
for (i = 0; i < dmamap->dm_nsegs; i++) {
vd[s].addr = dmamap->dm_segs[i].ds_addr;
vd[s].len = dmamap->dm_segs[i].ds_len;
if (!write)
vd[s].flags |= VRING_DESC_F_WRITE;
s = vd[s].next;
}
qe1->qe_next = s;
return 0;
}
int
virtio_enqueue_p(struct virtio_softc *sc, struct virtqueue *vq, int slot,
bus_dmamap_t dmamap, bus_addr_t start, bus_size_t len,
bool write)
{
struct vq_entry *qe1 = &vq->vq_entries[slot];
struct vring_desc *vd = qe1->qe_desc_base;
int s = qe1->qe_next;
KASSERT(s >= 0);
KASSERT(dmamap->dm_nsegs == 1); /* XXX */
KASSERT((dmamap->dm_segs[0].ds_len > start) &&
(dmamap->dm_segs[0].ds_len >= start + len));
vd[s].addr = dmamap->dm_segs[0].ds_addr + start;
vd[s].len = len;
if (!write)
vd[s].flags |= VRING_DESC_F_WRITE;
qe1->qe_next = vd[s].next;
return 0;
}
/*
* enqueue_commit: add it to the aring.
*/
int
virtio_enqueue_commit(struct virtio_softc *sc, struct virtqueue *vq, int slot,
bool notifynow)
{
struct vq_entry *qe1;
if (slot < 0) {
mutex_enter(&vq->vq_aring_lock);
goto notify;
}
vq_sync_descs(sc, vq, BUS_DMASYNC_PREWRITE);
qe1 = &vq->vq_entries[slot];
if (qe1->qe_indirect)
vq_sync_indirect(sc, vq, slot, BUS_DMASYNC_PREWRITE);
mutex_enter(&vq->vq_aring_lock);
vq->vq_avail->ring[(vq->vq_avail_idx++) % vq->vq_num] = slot;
notify:
if (notifynow) {
vq_sync_aring(sc, vq, BUS_DMASYNC_PREWRITE);
vq_sync_uring(sc, vq, BUS_DMASYNC_PREREAD);
membar_producer();
vq->vq_avail->idx = vq->vq_avail_idx;
vq_sync_aring(sc, vq, BUS_DMASYNC_PREWRITE);
membar_producer();
vq->vq_queued++;
vq_sync_uring(sc, vq, BUS_DMASYNC_POSTREAD);
membar_consumer();
if (!(vq->vq_used->flags & VRING_USED_F_NO_NOTIFY))
nbo_bus_space_write_2(sc->sc_iot, sc->sc_ioh,
VIRTIO_CONFIG_QUEUE_NOTIFY,
vq->vq_index);
}
mutex_exit(&vq->vq_aring_lock);
return 0;
}
/*
* enqueue_abort: rollback.
*/
int
virtio_enqueue_abort(struct virtio_softc *sc, struct virtqueue *vq, int slot)
{
struct vq_entry *qe = &vq->vq_entries[slot];
struct vring_desc *vd;
int s;
if (qe->qe_next < 0) {
vq_free_entry(vq, qe);
return 0;
}
s = slot;
vd = &vq->vq_desc[0];
while (vd[s].flags & VRING_DESC_F_NEXT) {
s = vd[s].next;
vq_free_entry(vq, qe);
qe = &vq->vq_entries[s];
}
vq_free_entry(vq, qe);
return 0;
}
/*
* Dequeue a request.
*/
/*
* dequeue: dequeue a request from uring; dmamap_sync for uring is
* already done in the interrupt handler.
*/
int
virtio_dequeue(struct virtio_softc *sc, struct virtqueue *vq,
int *slotp, int *lenp)
{
uint16_t slot, usedidx;
struct vq_entry *qe;
if (vq->vq_used_idx == vq->vq_used->idx)
return ENOENT;
mutex_enter(&vq->vq_uring_lock);
usedidx = vq->vq_used_idx++;
mutex_exit(&vq->vq_uring_lock);
usedidx %= vq->vq_num;
slot = vq->vq_used->ring[usedidx].id;
qe = &vq->vq_entries[slot];
if (qe->qe_indirect)
vq_sync_indirect(sc, vq, slot, BUS_DMASYNC_POSTWRITE);
if (slotp)
*slotp = slot;
if (lenp)
*lenp = vq->vq_used->ring[usedidx].len;
return 0;
}
/*
* dequeue_commit: complete dequeue; the slot is recycled for future use.
* if you forget to call this the slot will be leaked.
*/
int
virtio_dequeue_commit(struct virtio_softc *sc, struct virtqueue *vq, int slot)
{
struct vq_entry *qe = &vq->vq_entries[slot];
struct vring_desc *vd = &vq->vq_desc[0];
int s = slot;
while (vd[s].flags & VRING_DESC_F_NEXT) {
s = vd[s].next;
vq_free_entry(vq, qe);
qe = &vq->vq_entries[s];
}
vq_free_entry(vq, qe);
return 0;
}
MODULE(MODULE_CLASS_DRIVER, virtio, "pci");
#ifdef _MODULE
#include "ioconf.c"
#endif
static int
virtio_modcmd(modcmd_t cmd, void *opaque)
{
int error = 0;
#ifdef _MODULE
switch (cmd) {
case MODULE_CMD_INIT:
error = config_init_component(cfdriver_ioconf_virtio,
cfattach_ioconf_virtio, cfdata_ioconf_virtio);
break;
case MODULE_CMD_FINI:
error = config_fini_component(cfdriver_ioconf_virtio,
cfattach_ioconf_virtio, cfdata_ioconf_virtio);
break;
default:
error = ENOTTY;
break;
}
#endif
return error;
}
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