On Thu, Mar 5, 2026 at 7:28 PM <[email protected]> wrote:
>
> From: Xuemei Liu <[email protected]>
>
> Add save and restore funtction if kvm_irqchip_in_kernel() return
> true, it is to get and set IMSIC irqchip state from KVM kernel.
>
> Signed-off-by: Xuemei Liu <[email protected]>
> ---
> hw/intc/riscv_imsic.c | 171 +++++++++++++++++++++++++++++++---
> include/hw/intc/riscv_imsic.h | 3 +
> include/qemu/bitops.h | 9 +-
> migration/vmstate-types.c | 1 -
> 4 files changed, 165 insertions(+), 19 deletions(-)
>
> diff --git a/hw/intc/riscv_imsic.c b/hw/intc/riscv_imsic.c
> index 7c9a012033..1c9c706b03 100644
> --- a/hw/intc/riscv_imsic.c
> +++ b/hw/intc/riscv_imsic.c
> @@ -34,6 +34,7 @@
> #include "system/system.h"
> #include "system/kvm.h"
> #include "migration/vmstate.h"
> +#include "kvm/kvm_riscv.h"
>
> #define IMSIC_MMIO_PAGE_LE 0x00
> #define IMSIC_MMIO_PAGE_BE 0x04
> @@ -363,11 +364,16 @@ static void riscv_imsic_realize(DeviceState *dev, Error
> **errp)
> qdev_init_gpio_out(dev, imsic->external_irqs, imsic->num_pages);
>
> imsic->num_eistate = imsic->num_pages * imsic->num_irqs;
> - imsic->eidelivery = g_new0(uint32_t, imsic->num_pages);
> - imsic->eithreshold = g_new0(uint32_t, imsic->num_pages);
> imsic->eistate = g_new0(uint32_t, imsic->num_eistate);
> + } else {
> + imsic->nr_eix = 2 * BITS_TO_U64S(imsic->num_irqs);
> + imsic->eie = g_new0(uint32_t, imsic->nr_eix);
> + imsic->eip = g_new0(uint32_t, imsic->nr_eix);
> }
>
> + imsic->eidelivery = g_new0(uint32_t, imsic->num_pages);
> + imsic->eithreshold = g_new0(uint32_t, imsic->num_pages);
> +
> memory_region_init_io(&imsic->mmio, OBJECT(dev), &riscv_imsic_ops,
> imsic, TYPE_RISCV_IMSIC,
> IMSIC_MMIO_SIZE(imsic->num_pages));
> @@ -398,23 +404,17 @@ static const Property riscv_imsic_properties[] = {
> DEFINE_PROP_UINT32("num-irqs", RISCVIMSICState, num_irqs, 0),
> };
>
> -static bool riscv_imsic_state_needed(void *opaque)
> +static bool riscv_imsic_emul_state_needed(void *opaque)
> {
> return !kvm_irqchip_in_kernel();
> }
>
> -static const VMStateDescription vmstate_riscv_imsic = {
> - .name = "riscv_imsic",
> - .version_id = 2,
> - .minimum_version_id = 2,
> - .needed = riscv_imsic_state_needed,
> +static const VMStateDescription vmstate_riscv_imsic_emul = {
> + .name = "riscv_imsic_emul",
> + .version_id = 1,
> + .minimum_version_id = 1,
> + .needed = riscv_imsic_emul_state_needed,
> .fields = (const VMStateField[]) {
> - VMSTATE_VARRAY_UINT32(eidelivery, RISCVIMSICState,
> - num_pages, 0,
> - vmstate_info_uint32, uint32_t),
> - VMSTATE_VARRAY_UINT32(eithreshold, RISCVIMSICState,
> - num_pages, 0,
> - vmstate_info_uint32, uint32_t),
> VMSTATE_VARRAY_UINT32(eistate, RISCVIMSICState,
> num_eistate, 0,
> vmstate_info_uint32, uint32_t),
> @@ -422,6 +422,149 @@ static const VMStateDescription vmstate_riscv_imsic = {
> }
> };
>
> +static bool riscv_imsic_in_kernel_state_needed(void *opaque)
> +{
> + return kvm_irqchip_in_kernel();
> +}
> +
> +static int riscv_imsic_in_kernel_pre_save(void *opaque)
> +{
> + RISCVIMSICState *imsic = opaque;
> + RISCVCPU *rcpu = RISCV_CPU(cpu_by_arch_id(imsic->hartid));
> + bool is_32bit = riscv_cpu_is_32bit(rcpu);
> + uint32_t inc = 2;
> + uint64_t attr;
> +
> + if (is_32bit) {
> + inc = 1;
> + }
> +
> + if (kvm_irqchip_in_kernel()) {
> + for (uint32_t i = 0; i < imsic->nr_eix; i += inc) {
> + attr = KVM_DEV_RISCV_AIA_IMSIC_MKATTR(imsic->hartid,
> + ISELECT_IMSIC_EIE0 + i);
> + kvm_riscv_aia_access_reg(KVM_DEV_RISCV_AIA_GRP_IMSIC, attr,
> + imsic->eie + i, false);
> +
> + attr = KVM_DEV_RISCV_AIA_IMSIC_MKATTR(imsic->hartid,
> + ISELECT_IMSIC_EIP0 + i);
> + kvm_riscv_aia_access_reg(KVM_DEV_RISCV_AIA_GRP_IMSIC, attr,
> + imsic->eip + i, false);
> + }
> + }
> +
> + return 0;
> +}
> +
> +static int riscv_imsic_in_kernel_post_load(void *opaque, int version_id)
> +{
> + RISCVIMSICState *imsic = opaque;
> + RISCVCPU *rcpu = RISCV_CPU(cpu_by_arch_id(imsic->hartid));
> + bool is_32bit = riscv_cpu_is_32bit(rcpu);
> + uint32_t inc = 2;
> + uint64_t attr;
> +
> + if (is_32bit) {
> + inc = 1;
> + }
> +
> + if (kvm_irqchip_in_kernel()) {
> + for (uint32_t i = 0; i < imsic->nr_eix; i += inc) {
> + attr = KVM_DEV_RISCV_AIA_IMSIC_MKATTR(imsic->hartid,
> + ISELECT_IMSIC_EIE0 + i);
> + kvm_riscv_aia_access_reg(KVM_DEV_RISCV_AIA_GRP_IMSIC, attr,
> + imsic->eie + i, true);
> +
> + attr = KVM_DEV_RISCV_AIA_IMSIC_MKATTR(imsic->hartid,
> + ISELECT_IMSIC_EIP0 + i);
> + kvm_riscv_aia_access_reg(KVM_DEV_RISCV_AIA_GRP_IMSIC, attr,
> + imsic->eip + i, true);
> + }
> + }
> +
> + return 0;
> +}
> +
> +static const VMStateDescription vmstate_riscv_imsic_in_kernel = {
> + .name = "riscv_imsic_in_kernel",
> + .version_id = 1,
> + .minimum_version_id = 1,
> + .needed = riscv_imsic_in_kernel_state_needed,
> + .pre_save = riscv_imsic_in_kernel_pre_save,
> + .post_load = riscv_imsic_in_kernel_post_load,
> + .fields = (const VMStateField[]) {
> + VMSTATE_VARRAY_UINT32(eie, RISCVIMSICState,
> + nr_eix, 0,
> + vmstate_info_uint32, uint32_t),
> + VMSTATE_VARRAY_UINT32(eip, RISCVIMSICState,
> + nr_eix, 0,
> + vmstate_info_uint32, uint32_t),
> + VMSTATE_END_OF_LIST()
> + }
> +};
> +
> +static int riscv_imsic_pre_save(void *opaque)
> +{
> + RISCVIMSICState *imsic = opaque;
> + uint64_t attr;
> +
> + if (kvm_irqchip_in_kernel()) {
> + attr = KVM_DEV_RISCV_AIA_IMSIC_MKATTR(imsic->hartid,
> + ISELECT_IMSIC_EIDELIVERY);
> + kvm_riscv_aia_access_reg(KVM_DEV_RISCV_AIA_GRP_IMSIC, attr,
> + imsic->eidelivery, false);
> +
> + attr = KVM_DEV_RISCV_AIA_IMSIC_MKATTR(imsic->hartid,
> + ISELECT_IMSIC_EITHRESHOLD);
> + kvm_riscv_aia_access_reg(KVM_DEV_RISCV_AIA_GRP_IMSIC, attr,
> + imsic->eithreshold, false);
> + }
> +
> + return 0;
> +}
> +
> +static int riscv_imsic_post_load(void *opaque, int version_id)
> +{
> + RISCVIMSICState *imsic = opaque;
> + uint64_t attr;
> +
> + if (kvm_irqchip_in_kernel()) {
> + attr = KVM_DEV_RISCV_AIA_IMSIC_MKATTR(imsic->hartid,
> + ISELECT_IMSIC_EIDELIVERY);
> + kvm_riscv_aia_access_reg(KVM_DEV_RISCV_AIA_GRP_IMSIC, attr,
> + imsic->eidelivery, true);
> +
> + attr = KVM_DEV_RISCV_AIA_IMSIC_MKATTR(imsic->hartid,
> + ISELECT_IMSIC_EITHRESHOLD);
> + kvm_riscv_aia_access_reg(KVM_DEV_RISCV_AIA_GRP_IMSIC, attr,
> + imsic->eithreshold, true);
> + }
> +
> + return 0;
> +}
> +
> +static const VMStateDescription vmstate_riscv_imsic = {
> + .name = "riscv_imsic",
> + .version_id = 3,
> + .minimum_version_id = 3,
> + .pre_save = riscv_imsic_pre_save,
> + .post_load = riscv_imsic_post_load,
> + .fields = (const VMStateField[]) {
> + VMSTATE_VARRAY_UINT32(eidelivery, RISCVIMSICState,
> + num_pages, 0,
> + vmstate_info_uint32, uint32_t),
> + VMSTATE_VARRAY_UINT32(eithreshold, RISCVIMSICState,
> + num_pages, 0,
> + vmstate_info_uint32, uint32_t),
> + VMSTATE_END_OF_LIST()
> + },
> + .subsections = (const VMStateDescription * const []) {
> + &vmstate_riscv_imsic_emul,
> + &vmstate_riscv_imsic_in_kernel,
> + NULL
> + }
> +};
> +
> static void riscv_imsic_class_init(ObjectClass *klass, const void *data)
> {
> DeviceClass *dc = DEVICE_CLASS(klass);
> diff --git a/include/hw/intc/riscv_imsic.h b/include/hw/intc/riscv_imsic.h
> index fae999731d..2206d82e0c 100644
> --- a/include/hw/intc/riscv_imsic.h
> +++ b/include/hw/intc/riscv_imsic.h
> @@ -54,12 +54,15 @@ struct RISCVIMSICState {
> uint32_t *eidelivery;
> uint32_t *eithreshold;
> uint32_t *eistate;
> + uint32_t *eip;
> + uint32_t *eie;
>
> /* config */
> bool mmode;
> uint32_t hartid;
> uint32_t num_pages;
> uint32_t num_irqs;
> + uint32_t nr_eix;
> };
>
> DeviceState *riscv_imsic_create(hwaddr addr, uint32_t hartid, bool mmode,
> diff --git a/include/qemu/bitops.h b/include/qemu/bitops.h
> index c7b838a628..4b9b40f4c0 100644
> --- a/include/qemu/bitops.h
> +++ b/include/qemu/bitops.h
> @@ -16,10 +16,11 @@
> #include "host-utils.h"
> #include "atomic.h"
>
> -#define BITS_PER_BYTE CHAR_BIT
> -#define BITS_PER_LONG (sizeof (unsigned long) * BITS_PER_BYTE)
> -#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE *
> sizeof(long))
> -#define BITS_TO_U32S(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE *
> sizeof(uint32_t))
> +#define BITS_PER_BYTE CHAR_BIT
> +#define BITS_PER_LONG (sizeof(unsigned long) * BITS_PER_BYTE)
> +#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long))
> +#define BITS_TO_U64S(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE *
> sizeof(uint64_t))
> +#define BITS_TO_U32S(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE *
> sizeof(uint32_t))
This shouldn't be changed
Alistair
>
> #define BIT(nr) (1UL << (nr))
> #define BIT_ULL(nr) (1ULL << (nr))
> diff --git a/migration/vmstate-types.c b/migration/vmstate-types.c
> index 89cb211472..368a2922aa 100644
> --- a/migration/vmstate-types.c
> +++ b/migration/vmstate-types.c
> @@ -599,7 +599,6 @@ const VMStateInfo vmstate_info_tmp = {
> * is an array of 'unsigned long', which may be either 32 or 64 bits.
> */
> /* This is the number of 64 bit words sent over the wire */
> -#define BITS_TO_U64S(nr) DIV_ROUND_UP(nr, 64)
> static int get_bitmap(QEMUFile *f, void *pv, size_t size,
> const VMStateField *field)
> {
> --
> 2.27.0
>
