On 2/17/25 5:19 AM, Yong-Xuan Wang wrote:
KVM AIA is only needed to be set when the virt machine use the AIA MSI.
So we can move the KVM AIA configuration into virt_create_aia() to reduce
the condition checking.
Signed-off-by: Yong-Xuan Wang <yongxuan.w...@sifive.com>
---
Unfortunately this doesn't work.
The reason is that kvm_riscv_aia_create(), as it is now, is called only once
during virt_machine_init() and it's already handling initialization for each
socket:
for (socket = 0; socket < socket_count; socket++) {
socket_imsic_base = imsic_base + socket * (1U << group_shift);
hart_count = riscv_socket_hart_count(machine, socket);
base_hart = riscv_socket_first_hartid(machine, socket);
if (max_hart_per_socket < hart_count) {
max_hart_per_socket = hart_count;
}
for (i = 0; i < hart_count; i++) {
imsic_addr = socket_imsic_base + i * IMSIC_HART_SIZE(guest_bits);
ret = kvm_device_access(aia_fd, KVM_DEV_RISCV_AIA_GRP_ADDR,
KVM_DEV_RISCV_AIA_ADDR_IMSIC(i + base_hart),
&imsic_addr, true, NULL);
if (ret < 0) {
error_report("KVM AIA: failed to set the IMSIC address for hart
%d", i);
exit(1);
}
}
}
After this change, kvm_riscv_aia_create() is being called once for each socket
since it's
now being called inside virt_create_aia(). And this will cause errors when
running qemu-kvm
with more than one socket:
./qemu-system-riscv64 \
-machine virt,accel=kvm,aia=aplic-imsic -m 2G \
-object memory-backend-ram,size=1G,id=m0 \
-object memory-backend-ram,size=1G,id=m1 \
-smp 2,sockets=2,cores=1,threads=1 \
-numa node,memdev=m0,cpus=0,nodeid=0 \
-numa node,memdev=m1,cpus=1,nodeid=1 \
(...)
qemu-system-riscv64: KVM AIA: failed to set the IMSIC address for hart 0
To make this patch work we would need changes in kvm_riscv_aia_create() to
handle just the
current socket. The loop I mentioned above is one place, and there's another
place where
we set group_bits and group_shift if socket_count > 1.
To be honest I'm not sure if all these extra required changes are worth the
simplification
this patch is proposing.
Thanks,
Daniel
hw/riscv/virt.c | 79 +++++++++++++++++++++++--------------------------
1 file changed, 37 insertions(+), 42 deletions(-)
diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c
index dae46f4733cd..a52117ef71ee 100644
--- a/hw/riscv/virt.c
+++ b/hw/riscv/virt.c
@@ -58,14 +58,6 @@
#include "qapi/qapi-visit-common.h"
#include "hw/virtio/virtio-iommu.h"
-/* KVM AIA only supports APLIC MSI. APLIC Wired is always emulated by QEMU. */
-static bool virt_use_kvm_aia_aplic_imsic(RISCVVirtAIAType aia_type)
-{
- bool msimode = aia_type == VIRT_AIA_TYPE_APLIC_IMSIC;
-
- return riscv_is_kvm_aia_aplic_imsic(msimode);
-}
-
static bool virt_use_emulated_aplic(RISCVVirtAIAType aia_type)
{
bool msimode = aia_type == VIRT_AIA_TYPE_APLIC_IMSIC;
@@ -1298,10 +1290,12 @@ static DeviceState *virt_create_plic(const MemMapEntry
*memmap, int socket,
return ret;
}
-static DeviceState *virt_create_aia(RISCVVirtAIAType aia_type, int aia_guests,
+static DeviceState *virt_create_aia(RISCVVirtState *s,
const MemMapEntry *memmap, int socket,
int base_hartid, int hart_count)
{
+ RISCVVirtAIAType aia_type = s->aia_type;
+ int aia_guests = s->aia_guests;
int i;
hwaddr addr = 0;
uint32_t guest_bits;
@@ -1309,6 +1303,28 @@ static DeviceState *virt_create_aia(RISCVVirtAIAType
aia_type, int aia_guests,
DeviceState *aplic_m = NULL;
bool msimode = aia_type == VIRT_AIA_TYPE_APLIC_IMSIC;
+ if (!kvm_enabled()) {
+ /* Per-socket M-level APLIC */
+ aplic_m = riscv_aplic_create(memmap[VIRT_APLIC_M].base +
+ socket * memmap[VIRT_APLIC_M].size,
+ memmap[VIRT_APLIC_M].size,
+ (msimode) ? 0 : base_hartid,
+ (msimode) ? 0 : hart_count,
+ VIRT_IRQCHIP_NUM_SOURCES,
+ VIRT_IRQCHIP_NUM_PRIO_BITS,
+ msimode, true, NULL);
+ }
+
+ /* Per-socket S-level APLIC */
+ aplic_s = riscv_aplic_create(memmap[VIRT_APLIC_S].base +
+ socket * memmap[VIRT_APLIC_S].size,
+ memmap[VIRT_APLIC_S].size,
+ (msimode) ? 0 : base_hartid,
+ (msimode) ? 0 : hart_count,
+ VIRT_IRQCHIP_NUM_SOURCES,
+ VIRT_IRQCHIP_NUM_PRIO_BITS,
+ msimode, false, aplic_m);
+
if (msimode) {
if (!kvm_enabled()) {
/* Per-socket M-level IMSICs */
@@ -1329,32 +1345,20 @@ static DeviceState *virt_create_aia(RISCVVirtAIAType
aia_type, int aia_guests,
base_hartid + i, false, 1 + aia_guests,
VIRT_IRQCHIP_NUM_MSIS);
}
- }
- if (!kvm_enabled()) {
- /* Per-socket M-level APLIC */
- aplic_m = riscv_aplic_create(memmap[VIRT_APLIC_M].base +
- socket * memmap[VIRT_APLIC_M].size,
- memmap[VIRT_APLIC_M].size,
- (msimode) ? 0 : base_hartid,
- (msimode) ? 0 : hart_count,
- VIRT_IRQCHIP_NUM_SOURCES,
- VIRT_IRQCHIP_NUM_PRIO_BITS,
- msimode, true, NULL);
- }
- /* Per-socket S-level APLIC */
- aplic_s = riscv_aplic_create(memmap[VIRT_APLIC_S].base +
- socket * memmap[VIRT_APLIC_S].size,
- memmap[VIRT_APLIC_S].size,
- (msimode) ? 0 : base_hartid,
- (msimode) ? 0 : hart_count,
+ if (kvm_irqchip_in_kernel()) {
+ kvm_riscv_aia_create(MACHINE(s), IMSIC_MMIO_GROUP_MIN_SHIFT,
VIRT_IRQCHIP_NUM_SOURCES,
- VIRT_IRQCHIP_NUM_PRIO_BITS,
- msimode, false, aplic_m);
+ VIRT_IRQCHIP_NUM_MSIS,
+ memmap[VIRT_APLIC_S].base,
+ memmap[VIRT_IMSIC_S].base,
+ aia_guests);
+ }
- if (kvm_enabled() && msimode) {
- riscv_aplic_set_kvm_msicfgaddr(RISCV_APLIC(aplic_s), addr);
+ if (kvm_enabled()) {
+ riscv_aplic_set_kvm_msicfgaddr(RISCV_APLIC(aplic_s), addr);
+ }
}
return kvm_enabled() ? aplic_s : aplic_m;
@@ -1621,9 +1625,8 @@ static void virt_machine_init(MachineState *machine)
s->irqchip[i] = virt_create_plic(memmap, i,
base_hartid, hart_count);
} else {
- s->irqchip[i] = virt_create_aia(s->aia_type, s->aia_guests,
- memmap, i, base_hartid,
- hart_count);
+ s->irqchip[i] = virt_create_aia(s, memmap, i,
+ base_hartid, hart_count);
}
/* Try to use different IRQCHIP instance based device type */
@@ -1641,14 +1644,6 @@ static void virt_machine_init(MachineState *machine)
}
}
- if (kvm_enabled() && virt_use_kvm_aia_aplic_imsic(s->aia_type)) {
- kvm_riscv_aia_create(machine, IMSIC_MMIO_GROUP_MIN_SHIFT,
- VIRT_IRQCHIP_NUM_SOURCES, VIRT_IRQCHIP_NUM_MSIS,
- memmap[VIRT_APLIC_S].base,
- memmap[VIRT_IMSIC_S].base,
- s->aia_guests);
- }
-
if (riscv_is_32bit(&s->soc[0])) {
#if HOST_LONG_BITS == 64
/* limit RAM size in a 32-bit system */
