Module Name: src
Committed By: thorpej
Date: Sat Jan 6 06:59:33 UTC 2024
Modified Files:
src/sys/dev/virtio: virtio_mmio.c virtio_mmiovar.h
Log Message:
Perform VirtIO 1.0 feature negotation in the MMIO transport. This is
required for HV's that have MMIO-v2 and don't support transitional devices.
To generate a diff of this commit:
cvs rdiff -u -r1.12 -r1.13 src/sys/dev/virtio/virtio_mmio.c
cvs rdiff -u -r1.6 -r1.7 src/sys/dev/virtio/virtio_mmiovar.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/dev/virtio/virtio_mmio.c
diff -u src/sys/dev/virtio/virtio_mmio.c:1.12 src/sys/dev/virtio/virtio_mmio.c:1.13
--- src/sys/dev/virtio/virtio_mmio.c:1.12 Tue Jan 2 07:24:50 2024
+++ src/sys/dev/virtio/virtio_mmio.c Sat Jan 6 06:59:33 2024
@@ -1,4 +1,4 @@
-/* $NetBSD: virtio_mmio.c,v 1.12 2024/01/02 07:24:50 thorpej Exp $ */
+/* $NetBSD: virtio_mmio.c,v 1.13 2024/01/06 06:59:33 thorpej Exp $ */
/* $OpenBSD: virtio_mmio.c,v 1.2 2017/02/24 17:12:31 patrick Exp $ */
/*-
@@ -58,7 +58,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: virtio_mmio.c,v 1.12 2024/01/02 07:24:50 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: virtio_mmio.c,v 1.13 2024/01/06 06:59:33 thorpej Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -99,9 +99,6 @@ __KERNEL_RCSID(0, "$NetBSD: virtio_mmio.
#define VIRTIO_MMIO_V2_CONFIG_GEN 0x0fc
#define VIRTIO_MMIO_CONFIG 0x100
-#define VIRTIO_MMIO_INT_VRING (1 << 0)
-#define VIRTIO_MMIO_INT_CONFIG (1 << 1)
-
/*
* MMIO configuration space for virtio-mmio v1 is in guest byte order.
*
@@ -124,6 +121,7 @@ static void virtio_mmio_kick(struct virt
static uint16_t virtio_mmio_read_queue_size(struct virtio_softc *, uint16_t);
static void virtio_mmio_v1_setup_queue(struct virtio_softc *, uint16_t, uint64_t);
static void virtio_mmio_v2_setup_queue(struct virtio_softc *, uint16_t, uint64_t);
+static int virtio_mmio_get_status(struct virtio_softc *);
static void virtio_mmio_set_status(struct virtio_softc *, int);
static void virtio_mmio_negotiate_features(struct virtio_softc *, uint64_t);
static int virtio_mmio_alloc_interrupts(struct virtio_softc *);
@@ -232,6 +230,14 @@ virtio_mmio_v2_setup_queue(struct virtio
}
}
+static int
+virtio_mmio_get_status(struct virtio_softc *vsc)
+{
+ struct virtio_mmio_softc *sc = (struct virtio_mmio_softc *)vsc;
+
+ return virtio_mmio_reg_read(sc, VIRTIO_MMIO_STATUS);
+}
+
static void
virtio_mmio_set_status(struct virtio_softc *vsc, int status)
{
@@ -260,7 +266,8 @@ virtio_mmio_common_attach(struct virtio_
{
struct virtio_softc *vsc = &sc->sc_sc;
device_t self = vsc->sc_dev;
- uint32_t id, magic, ver;
+ uint32_t id, magic;
+ int virtio_vers;
magic = bus_space_read_4(sc->sc_iot, sc->sc_ioh,
VIRTIO_MMIO_MAGIC_VALUE);
@@ -276,25 +283,35 @@ virtio_mmio_common_attach(struct virtio_
vsc->sc_bus_endian = READ_ENDIAN;
vsc->sc_struct_endian = STRUCT_ENDIAN;
- ver = virtio_mmio_reg_read(sc, VIRTIO_MMIO_VERSION);
- switch (ver) {
+ sc->sc_mmio_vers = virtio_mmio_reg_read(sc, VIRTIO_MMIO_VERSION);
+ switch (sc->sc_mmio_vers) {
case 1:
/* we could use PAGE_SIZE, but virtio(4) assumes 4KiB for now */
virtio_mmio_reg_write(sc,
VIRTIO_MMIO_V1_GUEST_PAGE_SIZE, VIRTIO_PAGE_SIZE);
vsc->sc_ops = &virtio_mmio_v1_ops;
+ /*
+ * MMIO v1 ("legacy") is documented in the VirtIO 0.9.x
+ * draft(s) and uses the same page-oriented queue setup,
+ * so that's what we'll report as the VirtIO version.
+ */
+ virtio_vers = 0;
break;
case 2:
vsc->sc_ops = &virtio_mmio_v2_ops;
+ /*
+ * MMIO v2 is documented in the VirtIO 1.0 spec.
+ */
+ virtio_vers = 1;
break;
default:
aprint_error_dev(vsc->sc_dev,
- "unknown version 0x%08x; giving up\n", ver);
+ "unknown version 0x%08x; giving up\n", sc->sc_mmio_vers);
return;
}
- aprint_normal_dev(self, "VirtIO-MMIO v%d\n", ver);
+ aprint_normal_dev(self, "VirtIO-MMIO-v%u\n", sc->sc_mmio_vers);
id = virtio_mmio_reg_read(sc, VIRTIO_MMIO_DEVICE_ID);
if (id == 0) {
@@ -302,7 +319,7 @@ virtio_mmio_common_attach(struct virtio_
return;
}
- virtio_print_device_type(self, id, ver);
+ virtio_print_device_type(self, id, virtio_vers);
/* set up our device config tag */
vsc->sc_devcfg_iosize = sc->sc_iosize - VIRTIO_MMIO_CONFIG;
@@ -347,21 +364,89 @@ virtio_mmio_common_detach(struct virtio_
/*
* Feature negotiation.
+ *
+ * We fold pre-VirtIO-1.0 feature negotiation into this single routine
+ * because the "legacy" (MMIO-v1) also had the feature sel registers.
*/
static void
virtio_mmio_negotiate_features(struct virtio_softc *vsc, uint64_t
driver_features)
{
struct virtio_mmio_softc *sc = (struct virtio_mmio_softc *)vsc;
- uint32_t r;
+ device_t self = vsc->sc_dev;
+ uint64_t saved_driver_features = driver_features;
+ uint64_t device_features, negotiated;
+ uint32_t device_status;
+
+ driver_features |= VIRTIO_F_VERSION_1;
+ vsc->sc_active_features = 0;
virtio_mmio_reg_write(sc, VIRTIO_MMIO_DEVICE_FEATURES_SEL, 0);
- r = virtio_mmio_reg_read(sc, VIRTIO_MMIO_DEVICE_FEATURES);
- r &= driver_features;
+ device_features = virtio_mmio_reg_read(sc, VIRTIO_MMIO_DEVICE_FEATURES);
+ virtio_mmio_reg_write(sc, VIRTIO_MMIO_DEVICE_FEATURES_SEL, 1);
+ device_features |= (uint64_t)
+ virtio_mmio_reg_read(sc, VIRTIO_MMIO_DEVICE_FEATURES) << 32;
+
+ /* notify on empty is 0.9 only */
+ if (device_features & VIRTIO_F_VERSION_1) {
+ driver_features &= ~VIRTIO_F_NOTIFY_ON_EMPTY;
+ } else {
+ /*
+ * Require version 1 for MMIO-v2 transport.
+ */
+ if (sc->sc_mmio_vers >= 2) {
+ aprint_error_dev(self, "MMIO-v%u requires version 1\n",
+ sc->sc_mmio_vers);
+ virtio_mmio_set_status(vsc,
+ VIRTIO_CONFIG_DEVICE_STATUS_FAILED);
+ return;
+ }
+ /*
+ * If the driver requires version 1, but the device doesn't
+ * support it, fail now.
+ */
+ if (saved_driver_features & VIRTIO_F_VERSION_1) {
+ aprint_error_dev(self, "device rejected version 1\n");
+ virtio_mmio_set_status(vsc,
+ VIRTIO_CONFIG_DEVICE_STATUS_FAILED);
+ return;
+ }
+ }
+
+ negotiated = device_features & driver_features;
+
virtio_mmio_reg_write(sc, VIRTIO_MMIO_DRIVER_FEATURES_SEL, 0);
- virtio_mmio_reg_write(sc, VIRTIO_MMIO_DRIVER_FEATURES, r);
+ virtio_mmio_reg_write(sc, VIRTIO_MMIO_DRIVER_FEATURES,
+ (uint32_t)negotiated);
+ virtio_mmio_reg_write(sc, VIRTIO_MMIO_DRIVER_FEATURES_SEL, 1);
+ virtio_mmio_reg_write(sc, VIRTIO_MMIO_DRIVER_FEATURES,
+ (uint32_t)(negotiated >> 32));
+
+ /*
+ * FEATURES_OK status is not present pre-1.0.
+ */
+ if (device_features & VIRTIO_F_VERSION_1) {
+ virtio_mmio_set_status(vsc,
+ VIRTIO_CONFIG_DEVICE_STATUS_FEATURES_OK);
+ device_status = virtio_mmio_get_status(vsc);
+ if ((device_status &
+ VIRTIO_CONFIG_DEVICE_STATUS_FEATURES_OK) == 0) {
+ aprint_error_dev(self, "feature negotiation failed\n");
+ virtio_mmio_set_status(vsc,
+ VIRTIO_CONFIG_DEVICE_STATUS_FAILED);
+ return;
+ }
+ }
+
+ if (negotiated & VIRTIO_F_VERSION_1) {
+ /*
+ * All VirtIO 1.0 access is little-endian.
+ */
+ vsc->sc_bus_endian = LITTLE_ENDIAN;
+ vsc->sc_struct_endian = LITTLE_ENDIAN;
+ }
- vsc->sc_active_features = r;
+ vsc->sc_active_features = negotiated;
}
/*
@@ -377,10 +462,10 @@ virtio_mmio_intr(void *arg)
/* check and ack the interrupt */
isr = virtio_mmio_reg_read(sc, VIRTIO_MMIO_INTERRUPT_STATUS);
virtio_mmio_reg_write(sc, VIRTIO_MMIO_INTERRUPT_ACK, isr);
- if ((isr & VIRTIO_MMIO_INT_CONFIG) &&
+ if ((isr & VIRTIO_CONFIG_ISR_CONFIG_CHANGE) &&
(vsc->sc_config_change != NULL))
r = (vsc->sc_config_change)(vsc);
- if ((isr & VIRTIO_MMIO_INT_VRING) &&
+ if ((isr & VIRTIO_CONFIG_ISR_QUEUE_INTERRUPT) &&
(vsc->sc_intrhand != NULL)) {
if (vsc->sc_soft_ih != NULL)
softint_schedule(vsc->sc_soft_ih);
Index: src/sys/dev/virtio/virtio_mmiovar.h
diff -u src/sys/dev/virtio/virtio_mmiovar.h:1.6 src/sys/dev/virtio/virtio_mmiovar.h:1.7
--- src/sys/dev/virtio/virtio_mmiovar.h:1.6 Tue Jan 2 07:24:50 2024
+++ src/sys/dev/virtio/virtio_mmiovar.h Sat Jan 6 06:59:33 2024
@@ -1,4 +1,4 @@
-/* $NetBSD: virtio_mmiovar.h,v 1.6 2024/01/02 07:24:50 thorpej Exp $ */
+/* $NetBSD: virtio_mmiovar.h,v 1.7 2024/01/06 06:59:33 thorpej Exp $ */
/*
* Copyright (c) 2018 Jonathan A. Kollasch
* All rights reserved.
@@ -36,6 +36,7 @@ struct virtio_mmio_softc {
bus_space_tag_t sc_iot;
bus_space_handle_t sc_ioh;
bus_size_t sc_iosize;
+ uint32_t sc_mmio_vers;
bool sc_le_regs;
void *sc_ih;
