diff mbox series

[PULL,34/38] spapr: nested: Initialize the GSB elements lookup table.

Message ID 20240312165851.2240242-35-npiggin@gmail.com (mailing list archive)
State New, archived
Headers show
Series [PULL,01/38] target/ppc: Fix GDB SPR regnum indexing | expand

Commit Message

Nicholas Piggin March 12, 2024, 4:58 p.m. UTC
From: Harsh Prateek Bora <harshpb@linux.ibm.com>

Nested PAPR API provides a standard Guest State Buffer (GSB) format
with unique IDs for each guest state element for which get/set state is
supported by the API. Some of the elements are read-only and/or guest-wide.
Introducing additional required GSB elements and helper routines for state
exchange of each of the nested guest state elements for which get/set state
should be supported by the API.

[amachhiw: set the PCR whenever logical PVR is set]

Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Signed-off-by: Amit Machhiwal <amachhiw@linux.vnet.ibm.com>
Signed-off-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 hw/ppc/spapr_nested.c         | 487 +++++++++++++++++++++++++++++++++-
 include/hw/ppc/spapr_nested.h | 313 ++++++++++++++++++++++
 2 files changed, 798 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/hw/ppc/spapr_nested.c b/hw/ppc/spapr_nested.c
index 6a2ff963c6..cd7fa90350 100644
--- a/hw/ppc/spapr_nested.c
+++ b/hw/ppc/spapr_nested.c
@@ -19,6 +19,7 @@  void spapr_nested_reset(SpaprMachineState *spapr)
     } else {
         spapr->nested.api = 0;
         spapr->nested.capabilities_set = false;
+        spapr_nested_gsb_init();
     }
 }
 
@@ -136,7 +137,6 @@  static void nested_save_state(struct nested_ppc_state *save, PowerPCCPU *cpu)
     save->ppr = env->spr[SPR_PPR];
 
     if (spapr_nested_api(spapr) == NESTED_API_PAPR) {
-        save->pvr = env->spr[SPR_PVR];
         save->amor = env->spr[SPR_AMOR];
         save->dawr0 = env->spr[SPR_DAWR0];
         save->dawrx0 = env->spr[SPR_DAWRX0];
@@ -222,7 +222,6 @@  static void nested_load_state(PowerPCCPU *cpu, struct nested_ppc_state *load)
     env->spr[SPR_PPR] = load->ppr;
 
     if (spapr_nested_api(spapr) == NESTED_API_PAPR) {
-        env->spr[SPR_PVR] = load->pvr;
         env->spr[SPR_AMOR] = load->amor;
         env->spr[SPR_DAWR0] = load->dawr0;
         env->spr[SPR_DAWRX0] = load->dawrx0;
@@ -551,6 +550,485 @@  SpaprMachineStateNestedGuest *spapr_get_nested_guest(SpaprMachineState *spapr,
     return guest;
 }
 
+static bool spapr_nested_vcpu_check(SpaprMachineStateNestedGuest *guest,
+                                    target_ulong vcpuid, bool inoutbuf)
+{
+    struct SpaprMachineStateNestedGuestVcpu *vcpu;
+    /*
+     * Perform sanity checks for the provided vcpuid of a guest.
+     * For now, ensure its valid, allocated and enabled for use.
+     */
+
+    if (vcpuid >= PAPR_NESTED_GUEST_VCPU_MAX) {
+        return false;
+    }
+
+    if (!(vcpuid < guest->nr_vcpus)) {
+        return false;
+    }
+
+    vcpu = &guest->vcpus[vcpuid];
+    if (!vcpu->enabled) {
+        return false;
+    }
+
+    if (!inoutbuf) {
+        return true;
+    }
+
+    /* Check to see if the in/out buffers are registered */
+    if (vcpu->runbufin.addr && vcpu->runbufout.addr) {
+        return true;
+    }
+
+    return false;
+}
+
+static void *get_vcpu_state_ptr(SpaprMachineStateNestedGuest *guest,
+                              target_ulong vcpuid)
+{
+    assert(spapr_nested_vcpu_check(guest, vcpuid, false));
+    return &guest->vcpus[vcpuid].state;
+}
+
+static void *get_vcpu_ptr(SpaprMachineStateNestedGuest *guest,
+                                   target_ulong vcpuid)
+{
+    assert(spapr_nested_vcpu_check(guest, vcpuid, false));
+    return &guest->vcpus[vcpuid];
+}
+
+static void *get_guest_ptr(SpaprMachineStateNestedGuest *guest,
+                           target_ulong vcpuid)
+{
+    return guest; /* for GSBE_NESTED */
+}
+
+/*
+ * set=1 means the L1 is trying to set some state
+ * set=0 means the L1 is trying to get some state
+ */
+static void copy_state_8to8(void *a, void *b, bool set)
+{
+    /* set takes from the Big endian element_buf and sets internal buffer */
+
+    if (set) {
+        *(uint64_t *)a = be64_to_cpu(*(uint64_t *)b);
+    } else {
+        *(uint64_t *)b = cpu_to_be64(*(uint64_t *)a);
+    }
+}
+
+static void copy_state_4to4(void *a, void *b, bool set)
+{
+    if (set) {
+        *(uint32_t *)a = be32_to_cpu(*(uint32_t *)b);
+    } else {
+        *(uint32_t *)b = cpu_to_be32(*((uint32_t *)a));
+    }
+}
+
+static void copy_state_16to16(void *a, void *b, bool set)
+{
+    uint64_t *src, *dst;
+
+    if (set) {
+        src = b;
+        dst = a;
+
+        dst[1] = be64_to_cpu(src[0]);
+        dst[0] = be64_to_cpu(src[1]);
+    } else {
+        src = a;
+        dst = b;
+
+        dst[1] = cpu_to_be64(src[0]);
+        dst[0] = cpu_to_be64(src[1]);
+    }
+}
+
+static void copy_state_4to8(void *a, void *b, bool set)
+{
+    if (set) {
+        *(uint64_t *)a  = (uint64_t) be32_to_cpu(*(uint32_t *)b);
+    } else {
+        *(uint32_t *)b = cpu_to_be32((uint32_t) (*((uint64_t *)a)));
+    }
+}
+
+static void copy_state_pagetbl(void *a, void *b, bool set)
+{
+    uint64_t *pagetbl;
+    uint64_t *buf; /* 3 double words */
+    uint64_t rts;
+
+    assert(set);
+
+    pagetbl = a;
+    buf = b;
+
+    *pagetbl = be64_to_cpu(buf[0]);
+    /* as per ISA section 6.7.6.1 */
+    *pagetbl |= PATE0_HR; /* Host Radix bit is 1 */
+
+    /* RTS */
+    rts = be64_to_cpu(buf[1]);
+    assert(rts == 52);
+    rts = rts - 31; /* since radix tree size = 2^(RTS+31) */
+    *pagetbl |=  ((rts & 0x7) << 5); /* RTS2 is bit 56:58 */
+    *pagetbl |=  (((rts >> 3) & 0x3) << 61); /* RTS1 is bit 1:2 */
+
+    /* RPDS {Size = 2^(RPDS+3) , RPDS >=5} */
+    *pagetbl |= 63 - clz64(be64_to_cpu(buf[2])) - 3;
+}
+
+static void copy_state_proctbl(void *a, void *b, bool set)
+{
+    uint64_t *proctbl;
+    uint64_t *buf; /* 2 double words */
+
+    assert(set);
+
+    proctbl = a;
+    buf = b;
+    /* PRTB: Process Table Base */
+    *proctbl = be64_to_cpu(buf[0]);
+    /* PRTS: Process Table Size = 2^(12+PRTS) */
+    if (be64_to_cpu(buf[1]) == (1ULL << 12)) {
+            *proctbl |= 0;
+    } else if (be64_to_cpu(buf[1]) == (1ULL << 24)) {
+            *proctbl |= 12;
+    } else {
+        g_assert_not_reached();
+    }
+}
+
+static void copy_state_runbuf(void *a, void *b, bool set)
+{
+    uint64_t *buf; /* 2 double words */
+    struct SpaprMachineStateNestedGuestVcpuRunBuf *runbuf;
+
+    assert(set);
+
+    runbuf = a;
+    buf = b;
+
+    runbuf->addr = be64_to_cpu(buf[0]);
+    assert(runbuf->addr);
+
+    /* per spec */
+    assert(be64_to_cpu(buf[1]) <= 16384);
+
+    /*
+     * This will also hit in the input buffer but should be fine for
+     * now. If not we can split this function.
+     */
+    assert(be64_to_cpu(buf[1]) >= VCPU_OUT_BUF_MIN_SZ);
+
+    runbuf->size = be64_to_cpu(buf[1]);
+}
+
+/* tell the L1 how big we want the output vcpu run buffer */
+static void out_buf_min_size(void *a, void *b, bool set)
+{
+    uint64_t *buf; /* 1 double word */
+
+    assert(!set);
+
+    buf = b;
+
+    buf[0] = cpu_to_be64(VCPU_OUT_BUF_MIN_SZ);
+}
+
+static void copy_logical_pvr(void *a, void *b, bool set)
+{
+    SpaprMachineStateNestedGuest *guest;
+    uint32_t *buf; /* 1 word */
+    uint32_t *pvr_logical_ptr;
+    uint32_t pvr_logical;
+    target_ulong pcr = 0;
+
+    pvr_logical_ptr = a;
+    buf = b;
+
+    if (!set) {
+        buf[0] = cpu_to_be32(*pvr_logical_ptr);
+        return;
+    }
+
+    pvr_logical = be32_to_cpu(buf[0]);
+
+    *pvr_logical_ptr = pvr_logical;
+
+    if (*pvr_logical_ptr) {
+        switch (*pvr_logical_ptr) {
+        case CPU_POWERPC_LOGICAL_3_10:
+            pcr = PCR_COMPAT_3_10 | PCR_COMPAT_3_00;
+            break;
+        case CPU_POWERPC_LOGICAL_3_00:
+            pcr = PCR_COMPAT_3_00;
+            break;
+        default:
+            qemu_log_mask(LOG_GUEST_ERROR,
+                          "Could not set PCR for LPVR=0x%08x\n",
+                          *pvr_logical_ptr);
+            return;
+        }
+    }
+
+    guest = container_of(pvr_logical_ptr,
+                         struct SpaprMachineStateNestedGuest,
+                         pvr_logical);
+    for (int i = 0; i < guest->nr_vcpus; i++) {
+        guest->vcpus[i].state.pcr = ~pcr | HVMASK_PCR;
+    }
+}
+
+static void copy_tb_offset(void *a, void *b, bool set)
+{
+    SpaprMachineStateNestedGuest *guest;
+    uint64_t *buf; /* 1 double word */
+    uint64_t *tb_offset_ptr;
+    uint64_t tb_offset;
+
+    tb_offset_ptr = a;
+    buf = b;
+
+    if (!set) {
+        buf[0] = cpu_to_be64(*tb_offset_ptr);
+        return;
+    }
+
+    tb_offset = be64_to_cpu(buf[0]);
+    /* need to copy this to the individual tb_offset for each vcpu */
+    guest = container_of(tb_offset_ptr,
+                         struct SpaprMachineStateNestedGuest,
+                         tb_offset);
+    for (int i = 0; i < guest->nr_vcpus; i++) {
+        guest->vcpus[i].tb_offset = tb_offset;
+    }
+}
+
+static void copy_state_hdecr(void *a, void *b, bool set)
+{
+    uint64_t *buf; /* 1 double word */
+    uint64_t *hdecr_expiry_tb;
+
+    hdecr_expiry_tb = a;
+    buf = b;
+
+    if (!set) {
+        buf[0] = cpu_to_be64(*hdecr_expiry_tb);
+        return;
+    }
+
+    *hdecr_expiry_tb = be64_to_cpu(buf[0]);
+}
+
+struct guest_state_element_type guest_state_element_types[] = {
+    GUEST_STATE_ELEMENT_NOP(GSB_HV_VCPU_IGNORED_ID, 0),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR0,  gpr[0]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR1,  gpr[1]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR2,  gpr[2]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR3,  gpr[3]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR4,  gpr[4]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR5,  gpr[5]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR6,  gpr[6]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR7,  gpr[7]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR8,  gpr[8]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR9,  gpr[9]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR10, gpr[10]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR11, gpr[11]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR12, gpr[12]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR13, gpr[13]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR14, gpr[14]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR15, gpr[15]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR16, gpr[16]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR17, gpr[17]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR18, gpr[18]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR19, gpr[19]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR20, gpr[20]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR21, gpr[21]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR22, gpr[22]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR23, gpr[23]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR24, gpr[24]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR25, gpr[25]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR26, gpr[26]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR27, gpr[27]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR28, gpr[28]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR29, gpr[29]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR30, gpr[30]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_GPR31, gpr[31]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_NIA, nip),
+    GSE_ENV_DWM(GSB_VCPU_SPR_MSR, msr, HVMASK_MSR),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_CTR, ctr),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_LR, lr),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_XER, xer),
+    GUEST_STATE_ELEMENT_ENV_WW(GSB_VCPU_SPR_CR, cr),
+    GUEST_STATE_ELEMENT_NOP_DW(GSB_VCPU_SPR_MMCR3),
+    GUEST_STATE_ELEMENT_NOP_DW(GSB_VCPU_SPR_SIER2),
+    GUEST_STATE_ELEMENT_NOP_DW(GSB_VCPU_SPR_SIER3),
+    GUEST_STATE_ELEMENT_NOP_W(GSB_VCPU_SPR_WORT),
+    GSE_ENV_DWM(GSB_VCPU_SPR_LPCR, lpcr, HVMASK_LPCR),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_AMOR, amor),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_HFSCR, hfscr),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_DAWR0, dawr0),
+    GUEST_STATE_ELEMENT_ENV_W(GSB_VCPU_SPR_DAWRX0, dawrx0),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_CIABR, ciabr),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_PURR,  purr),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_SPURR, spurr),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_IC,    ic),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_VTB,   vtb),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_HDAR,  hdar),
+    GUEST_STATE_ELEMENT_ENV_W(GSB_VCPU_SPR_HDSISR, hdsisr),
+    GUEST_STATE_ELEMENT_ENV_W(GSB_VCPU_SPR_HEIR,   heir),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_ASDR,  asdr),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_SRR0,  srr0),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_SRR1,  srr1),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_SPRG0, sprg0),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_SPRG1, sprg1),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_SPRG2, sprg2),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_SPRG3, sprg3),
+    GUEST_STATE_ELEMENT_ENV_W(GSB_VCPU_SPR_PIDR,   pidr),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_CFAR,  cfar),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_PPR,   ppr),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_DAWR1, dawr1),
+    GUEST_STATE_ELEMENT_ENV_W(GSB_VCPU_SPR_DAWRX1, dawrx1),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_DEXCR, dexcr),
+    GSE_ENV_DWM(GSB_VCPU_SPR_HDEXCR, hdexcr, HVMASK_HDEXCR),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_HASHKEYR, hashkeyr),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_HASHPKEYR, hashpkeyr),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR0, vsr[0]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR1, vsr[1]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR2, vsr[2]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR3, vsr[3]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR4, vsr[4]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR5, vsr[5]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR6, vsr[6]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR7, vsr[7]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR8, vsr[8]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR9, vsr[9]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR10, vsr[10]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR11, vsr[11]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR12, vsr[12]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR13, vsr[13]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR14, vsr[14]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR15, vsr[15]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR16, vsr[16]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR17, vsr[17]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR18, vsr[18]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR19, vsr[19]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR20, vsr[20]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR21, vsr[21]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR22, vsr[22]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR23, vsr[23]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR24, vsr[24]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR25, vsr[25]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR26, vsr[26]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR27, vsr[27]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR28, vsr[28]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR29, vsr[29]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR30, vsr[30]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR31, vsr[31]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR32, vsr[32]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR33, vsr[33]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR34, vsr[34]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR35, vsr[35]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR36, vsr[36]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR37, vsr[37]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR38, vsr[38]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR39, vsr[39]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR40, vsr[40]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR41, vsr[41]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR42, vsr[42]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR43, vsr[43]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR44, vsr[44]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR45, vsr[45]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR46, vsr[46]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR47, vsr[47]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR48, vsr[48]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR49, vsr[49]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR50, vsr[50]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR51, vsr[51]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR52, vsr[52]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR53, vsr[53]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR54, vsr[54]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR55, vsr[55]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR56, vsr[56]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR57, vsr[57]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR58, vsr[58]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR59, vsr[59]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR60, vsr[60]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR61, vsr[61]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR62, vsr[62]),
+    GUEST_STATE_ELEMENT_ENV_QW(GSB_VCPU_SPR_VSR63, vsr[63]),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_EBBHR, ebbhr),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_TAR,   tar),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_EBBRR, ebbrr),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_BESCR, bescr),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_IAMR,  iamr),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_AMR,   amr),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_UAMOR, uamor),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_DSCR,  dscr),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_FSCR,  fscr),
+    GUEST_STATE_ELEMENT_ENV_W(GSB_VCPU_SPR_PSPB,   pspb),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_CTRL,  ctrl),
+    GUEST_STATE_ELEMENT_ENV_W(GSB_VCPU_SPR_VRSAVE, vrsave),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_DAR,   dar),
+    GUEST_STATE_ELEMENT_ENV_W(GSB_VCPU_SPR_DSISR,  dsisr),
+    GUEST_STATE_ELEMENT_ENV_W(GSB_VCPU_SPR_PMC1,   pmc1),
+    GUEST_STATE_ELEMENT_ENV_W(GSB_VCPU_SPR_PMC2,   pmc2),
+    GUEST_STATE_ELEMENT_ENV_W(GSB_VCPU_SPR_PMC3,   pmc3),
+    GUEST_STATE_ELEMENT_ENV_W(GSB_VCPU_SPR_PMC4,   pmc4),
+    GUEST_STATE_ELEMENT_ENV_W(GSB_VCPU_SPR_PMC5,   pmc5),
+    GUEST_STATE_ELEMENT_ENV_W(GSB_VCPU_SPR_PMC6,   pmc6),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_MMCR0, mmcr0),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_MMCR1, mmcr1),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_MMCR2, mmcr2),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_MMCRA, mmcra),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_SDAR , sdar),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_SIAR , siar),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_SIER , sier),
+    GUEST_STATE_ELEMENT_ENV_WW(GSB_VCPU_SPR_VSCR,  vscr),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_SPR_FPSCR, fpscr),
+    GUEST_STATE_ELEMENT_ENV_DW(GSB_VCPU_DEC_EXPIRE_TB, dec_expiry_tb),
+    GSBE_NESTED(GSB_PART_SCOPED_PAGETBL, 0x18, parttbl[0],  copy_state_pagetbl),
+    GSBE_NESTED(GSB_PROCESS_TBL,         0x10, parttbl[1],  copy_state_proctbl),
+    GSBE_NESTED(GSB_VCPU_LPVR,           0x4,  pvr_logical, copy_logical_pvr),
+    GSBE_NESTED_MSK(GSB_TB_OFFSET, 0x8, tb_offset, copy_tb_offset,
+                    HVMASK_TB_OFFSET),
+    GSBE_NESTED_VCPU(GSB_VCPU_IN_BUFFER, 0x10, runbufin,    copy_state_runbuf),
+    GSBE_NESTED_VCPU(GSB_VCPU_OUT_BUFFER, 0x10, runbufout,   copy_state_runbuf),
+    GSBE_NESTED_VCPU(GSB_VCPU_OUT_BUF_MIN_SZ, 0x8, runbufout, out_buf_min_size),
+    GSBE_NESTED_VCPU(GSB_VCPU_HDEC_EXPIRY_TB, 0x8, hdecr_expiry_tb,
+                     copy_state_hdecr)
+};
+
+void spapr_nested_gsb_init(void)
+{
+    struct guest_state_element_type *type;
+
+    /* Init the guest state elements lookup table, flags for now */
+    for (int i = 0; i < ARRAY_SIZE(guest_state_element_types); i++) {
+        type = &guest_state_element_types[i];
+
+        assert(type->id <= GSB_LAST);
+        if (type->id >= GSB_VCPU_SPR_HDAR)
+            /* 0xf000 - 0xf005 Thread + RO */
+            type->flags = GUEST_STATE_ELEMENT_TYPE_FLAG_READ_ONLY;
+        else if (type->id >= GSB_VCPU_IN_BUFFER)
+            /* 0x0c00 - 0xf000 Thread + RW */
+            type->flags = 0;
+        else if (type->id >= GSB_VCPU_LPVR)
+            /* 0x0003 - 0x0bff Guest + RW */
+            type->flags = GUEST_STATE_ELEMENT_TYPE_FLAG_GUEST_WIDE;
+        else if (type->id >= GSB_HV_VCPU_STATE_SIZE)
+            /* 0x0001 - 0x0002 Guest + RO */
+            type->flags = GUEST_STATE_ELEMENT_TYPE_FLAG_READ_ONLY |
+                          GUEST_STATE_ELEMENT_TYPE_FLAG_GUEST_WIDE;
+    }
+}
+
 static target_ulong h_guest_get_capabilities(PowerPCCPU *cpu,
                                              SpaprMachineState *spapr,
                                              target_ulong opcode,
@@ -854,4 +1332,9 @@  void spapr_unregister_nested_papr(void)
     /* DO NOTHING */
 }
 
+void spapr_nested_gsb_init(void)
+{
+    /* DO NOTHING */
+}
+
 #endif
diff --git a/include/hw/ppc/spapr_nested.h b/include/hw/ppc/spapr_nested.h
index d232014ccb..3da02df7bb 100644
--- a/include/hw/ppc/spapr_nested.h
+++ b/include/hw/ppc/spapr_nested.h
@@ -3,6 +3,191 @@ 
 
 #include "target/ppc/cpu.h"
 
+/* Guest State Buffer Element IDs */
+#define GSB_HV_VCPU_IGNORED_ID  0x0000 /* An element whose value is ignored */
+#define GSB_HV_VCPU_STATE_SIZE  0x0001 /* HV internal format VCPU state size */
+#define GSB_VCPU_OUT_BUF_MIN_SZ 0x0002 /* Min size of the Run VCPU o/p buffer */
+#define GSB_VCPU_LPVR           0x0003 /* Logical PVR */
+#define GSB_TB_OFFSET           0x0004 /* Timebase Offset */
+#define GSB_PART_SCOPED_PAGETBL 0x0005 /* Partition Scoped Page Table */
+#define GSB_PROCESS_TBL         0x0006 /* Process Table */
+                    /* RESERVED 0x0007 - 0x0BFF */
+#define GSB_VCPU_IN_BUFFER      0x0C00 /* Run VCPU Input Buffer */
+#define GSB_VCPU_OUT_BUFFER     0x0C01 /* Run VCPU Out Buffer */
+#define GSB_VCPU_VPA            0x0C02 /* HRA to Guest VCPU VPA */
+                    /* RESERVED 0x0C03 - 0x0FFF */
+#define GSB_VCPU_GPR0           0x1000
+#define GSB_VCPU_GPR1           0x1001
+#define GSB_VCPU_GPR2           0x1002
+#define GSB_VCPU_GPR3           0x1003
+#define GSB_VCPU_GPR4           0x1004
+#define GSB_VCPU_GPR5           0x1005
+#define GSB_VCPU_GPR6           0x1006
+#define GSB_VCPU_GPR7           0x1007
+#define GSB_VCPU_GPR8           0x1008
+#define GSB_VCPU_GPR9           0x1009
+#define GSB_VCPU_GPR10          0x100A
+#define GSB_VCPU_GPR11          0x100B
+#define GSB_VCPU_GPR12          0x100C
+#define GSB_VCPU_GPR13          0x100D
+#define GSB_VCPU_GPR14          0x100E
+#define GSB_VCPU_GPR15          0x100F
+#define GSB_VCPU_GPR16          0x1010
+#define GSB_VCPU_GPR17          0x1011
+#define GSB_VCPU_GPR18          0x1012
+#define GSB_VCPU_GPR19          0x1013
+#define GSB_VCPU_GPR20          0x1014
+#define GSB_VCPU_GPR21          0x1015
+#define GSB_VCPU_GPR22          0x1016
+#define GSB_VCPU_GPR23          0x1017
+#define GSB_VCPU_GPR24          0x1018
+#define GSB_VCPU_GPR25          0x1019
+#define GSB_VCPU_GPR26          0x101A
+#define GSB_VCPU_GPR27          0x101B
+#define GSB_VCPU_GPR28          0x101C
+#define GSB_VCPU_GPR29          0x101D
+#define GSB_VCPU_GPR30          0x101E
+#define GSB_VCPU_GPR31          0x101F
+#define GSB_VCPU_HDEC_EXPIRY_TB 0x1020
+#define GSB_VCPU_SPR_NIA        0x1021
+#define GSB_VCPU_SPR_MSR        0x1022
+#define GSB_VCPU_SPR_LR         0x1023
+#define GSB_VCPU_SPR_XER        0x1024
+#define GSB_VCPU_SPR_CTR        0x1025
+#define GSB_VCPU_SPR_CFAR       0x1026
+#define GSB_VCPU_SPR_SRR0       0x1027
+#define GSB_VCPU_SPR_SRR1       0x1028
+#define GSB_VCPU_SPR_DAR        0x1029
+#define GSB_VCPU_DEC_EXPIRE_TB  0x102A
+#define GSB_VCPU_SPR_VTB        0x102B
+#define GSB_VCPU_SPR_LPCR       0x102C
+#define GSB_VCPU_SPR_HFSCR      0x102D
+#define GSB_VCPU_SPR_FSCR       0x102E
+#define GSB_VCPU_SPR_FPSCR      0x102F
+#define GSB_VCPU_SPR_DAWR0      0x1030
+#define GSB_VCPU_SPR_DAWR1      0x1031
+#define GSB_VCPU_SPR_CIABR      0x1032
+#define GSB_VCPU_SPR_PURR       0x1033
+#define GSB_VCPU_SPR_SPURR      0x1034
+#define GSB_VCPU_SPR_IC         0x1035
+#define GSB_VCPU_SPR_SPRG0      0x1036
+#define GSB_VCPU_SPR_SPRG1      0x1037
+#define GSB_VCPU_SPR_SPRG2      0x1038
+#define GSB_VCPU_SPR_SPRG3      0x1039
+#define GSB_VCPU_SPR_PPR        0x103A
+#define GSB_VCPU_SPR_MMCR0      0x103B
+#define GSB_VCPU_SPR_MMCR1      0x103C
+#define GSB_VCPU_SPR_MMCR2      0x103D
+#define GSB_VCPU_SPR_MMCR3      0x103E
+#define GSB_VCPU_SPR_MMCRA      0x103F
+#define GSB_VCPU_SPR_SIER       0x1040
+#define GSB_VCPU_SPR_SIER2      0x1041
+#define GSB_VCPU_SPR_SIER3      0x1042
+#define GSB_VCPU_SPR_BESCR      0x1043
+#define GSB_VCPU_SPR_EBBHR      0x1044
+#define GSB_VCPU_SPR_EBBRR      0x1045
+#define GSB_VCPU_SPR_AMR        0x1046
+#define GSB_VCPU_SPR_IAMR       0x1047
+#define GSB_VCPU_SPR_AMOR       0x1048
+#define GSB_VCPU_SPR_UAMOR      0x1049
+#define GSB_VCPU_SPR_SDAR       0x104A
+#define GSB_VCPU_SPR_SIAR       0x104B
+#define GSB_VCPU_SPR_DSCR       0x104C
+#define GSB_VCPU_SPR_TAR        0x104D
+#define GSB_VCPU_SPR_DEXCR      0x104E
+#define GSB_VCPU_SPR_HDEXCR     0x104F
+#define GSB_VCPU_SPR_HASHKEYR   0x1050
+#define GSB_VCPU_SPR_HASHPKEYR  0x1051
+#define GSB_VCPU_SPR_CTRL       0x1052
+                    /* RESERVED 0x1053 - 0x1FFF */
+#define GSB_VCPU_SPR_CR         0x2000
+#define GSB_VCPU_SPR_PIDR       0x2001
+#define GSB_VCPU_SPR_DSISR      0x2002
+#define GSB_VCPU_SPR_VSCR       0x2003
+#define GSB_VCPU_SPR_VRSAVE     0x2004
+#define GSB_VCPU_SPR_DAWRX0     0x2005
+#define GSB_VCPU_SPR_DAWRX1     0x2006
+#define GSB_VCPU_SPR_PMC1       0x2007
+#define GSB_VCPU_SPR_PMC2       0x2008
+#define GSB_VCPU_SPR_PMC3       0x2009
+#define GSB_VCPU_SPR_PMC4       0x200A
+#define GSB_VCPU_SPR_PMC5       0x200B
+#define GSB_VCPU_SPR_PMC6       0x200C
+#define GSB_VCPU_SPR_WORT       0x200D
+#define GSB_VCPU_SPR_PSPB       0x200E
+                    /* RESERVED 0x200F - 0x2FFF */
+#define GSB_VCPU_SPR_VSR0       0x3000
+#define GSB_VCPU_SPR_VSR1       0x3001
+#define GSB_VCPU_SPR_VSR2       0x3002
+#define GSB_VCPU_SPR_VSR3       0x3003
+#define GSB_VCPU_SPR_VSR4       0x3004
+#define GSB_VCPU_SPR_VSR5       0x3005
+#define GSB_VCPU_SPR_VSR6       0x3006
+#define GSB_VCPU_SPR_VSR7       0x3007
+#define GSB_VCPU_SPR_VSR8       0x3008
+#define GSB_VCPU_SPR_VSR9       0x3009
+#define GSB_VCPU_SPR_VSR10      0x300A
+#define GSB_VCPU_SPR_VSR11      0x300B
+#define GSB_VCPU_SPR_VSR12      0x300C
+#define GSB_VCPU_SPR_VSR13      0x300D
+#define GSB_VCPU_SPR_VSR14      0x300E
+#define GSB_VCPU_SPR_VSR15      0x300F
+#define GSB_VCPU_SPR_VSR16      0x3010
+#define GSB_VCPU_SPR_VSR17      0x3011
+#define GSB_VCPU_SPR_VSR18      0x3012
+#define GSB_VCPU_SPR_VSR19      0x3013
+#define GSB_VCPU_SPR_VSR20      0x3014
+#define GSB_VCPU_SPR_VSR21      0x3015
+#define GSB_VCPU_SPR_VSR22      0x3016
+#define GSB_VCPU_SPR_VSR23      0x3017
+#define GSB_VCPU_SPR_VSR24      0x3018
+#define GSB_VCPU_SPR_VSR25      0x3019
+#define GSB_VCPU_SPR_VSR26      0x301A
+#define GSB_VCPU_SPR_VSR27      0x301B
+#define GSB_VCPU_SPR_VSR28      0x301C
+#define GSB_VCPU_SPR_VSR29      0x301D
+#define GSB_VCPU_SPR_VSR30      0x301E
+#define GSB_VCPU_SPR_VSR31      0x301F
+#define GSB_VCPU_SPR_VSR32      0x3020
+#define GSB_VCPU_SPR_VSR33      0x3021
+#define GSB_VCPU_SPR_VSR34      0x3022
+#define GSB_VCPU_SPR_VSR35      0x3023
+#define GSB_VCPU_SPR_VSR36      0x3024
+#define GSB_VCPU_SPR_VSR37      0x3025
+#define GSB_VCPU_SPR_VSR38      0x3026
+#define GSB_VCPU_SPR_VSR39      0x3027
+#define GSB_VCPU_SPR_VSR40      0x3028
+#define GSB_VCPU_SPR_VSR41      0x3029
+#define GSB_VCPU_SPR_VSR42      0x302A
+#define GSB_VCPU_SPR_VSR43      0x302B
+#define GSB_VCPU_SPR_VSR44      0x302C
+#define GSB_VCPU_SPR_VSR45      0x302D
+#define GSB_VCPU_SPR_VSR46      0x302E
+#define GSB_VCPU_SPR_VSR47      0x302F
+#define GSB_VCPU_SPR_VSR48      0x3030
+#define GSB_VCPU_SPR_VSR49      0x3031
+#define GSB_VCPU_SPR_VSR50      0x3032
+#define GSB_VCPU_SPR_VSR51      0x3033
+#define GSB_VCPU_SPR_VSR52      0x3034
+#define GSB_VCPU_SPR_VSR53      0x3035
+#define GSB_VCPU_SPR_VSR54      0x3036
+#define GSB_VCPU_SPR_VSR55      0x3037
+#define GSB_VCPU_SPR_VSR56      0x3038
+#define GSB_VCPU_SPR_VSR57      0x3039
+#define GSB_VCPU_SPR_VSR58      0x303A
+#define GSB_VCPU_SPR_VSR59      0x303B
+#define GSB_VCPU_SPR_VSR60      0x303C
+#define GSB_VCPU_SPR_VSR61      0x303D
+#define GSB_VCPU_SPR_VSR62      0x303E
+#define GSB_VCPU_SPR_VSR63      0x303F
+                    /* RESERVED 0x3040 - 0xEFFF */
+#define GSB_VCPU_SPR_HDAR       0xF000
+#define GSB_VCPU_SPR_HDSISR     0xF001
+#define GSB_VCPU_SPR_HEIR       0xF002
+#define GSB_VCPU_SPR_ASDR       0xF003
+/* End of list of Guest State Buffer Element IDs */
+#define GSB_LAST                GSB_VCPU_SPR_ASDR
+
 typedef struct SpaprMachineStateNested {
     uint64_t ptcr;
     uint8_t api;
@@ -16,6 +201,8 @@  typedef struct SpaprMachineStateNested {
 typedef struct SpaprMachineStateNestedGuest {
     uint32_t pvr_logical;
     unsigned long nr_vcpus;
+    uint64_t parttbl[2];
+    uint64_t tb_offset;
     struct SpaprMachineStateNestedGuestVcpu *vcpus;
 } SpaprMachineStateNestedGuest;
 
@@ -31,6 +218,109 @@  typedef struct SpaprMachineStateNestedGuest {
 #define PAPR_NESTED_GUEST_MAX         4096
 #define H_GUEST_DELETE_ALL_FLAG       0x8000000000000000ULL
 #define PAPR_NESTED_GUEST_VCPU_MAX    2048
+#define VCPU_OUT_BUF_MIN_SZ           0x80ULL
+#define HVMASK_DEFAULT                0xffffffffffffffff
+#define HVMASK_LPCR                   0x0070000003820800
+#define HVMASK_MSR                    0xEBFFFFFFFFBFEFFF
+#define HVMASK_HDEXCR                 0x00000000FFFFFFFF
+#define HVMASK_TB_OFFSET              0x000000FFFFFFFFFF
+
+/*
+ * As per ISA v3.1B, following bits are reserved:
+ *      0:2
+ *      4:57  (ISA mentions bit 58 as well but it should be used for P10)
+ *      61:63 (hence, haven't included PCR bits for v2.06 and v2.05
+ *             in LOW BITS)
+ */
+#define PCR_LOW_BITS   (PCR_COMPAT_3_10 | PCR_COMPAT_3_00)
+#define HVMASK_PCR     (~PCR_LOW_BITS)
+
+#define GUEST_STATE_ELEMENT(i, sz, s, f, ptr, c) { \
+    .id = (i),                                     \
+    .size = (sz),                                  \
+    .location = ptr,                               \
+    .offset = offsetof(struct s, f),               \
+    .copy = (c)                                    \
+}
+
+#define GSBE_NESTED(i, sz, f, c) {                             \
+    .id = (i),                                                 \
+    .size = (sz),                                              \
+    .location = get_guest_ptr,                                 \
+    .offset = offsetof(struct SpaprMachineStateNestedGuest, f),\
+    .copy = (c),                                               \
+    .mask = HVMASK_DEFAULT                                     \
+}
+
+#define GSBE_NESTED_MSK(i, sz, f, c, m) {                      \
+    .id = (i),                                                 \
+    .size = (sz),                                              \
+    .location = get_guest_ptr,                                 \
+    .offset = offsetof(struct SpaprMachineStateNestedGuest, f),\
+    .copy = (c),                                               \
+    .mask = (m)                                                \
+}
+
+#define GSBE_NESTED_VCPU(i, sz, f, c) {                            \
+    .id = (i),                                                     \
+    .size = (sz),                                                  \
+    .location = get_vcpu_ptr,                                      \
+    .offset = offsetof(struct SpaprMachineStateNestedGuestVcpu, f),\
+    .copy = (c),                                                   \
+    .mask = HVMASK_DEFAULT                                         \
+}
+
+#define GUEST_STATE_ELEMENT_NOP(i, sz) { \
+    .id = (i),                             \
+    .size = (sz),                          \
+    .location = NULL,                      \
+    .offset = 0,                           \
+    .copy = NULL,                          \
+    .mask = HVMASK_DEFAULT                 \
+}
+
+#define GUEST_STATE_ELEMENT_NOP_DW(i)   \
+        GUEST_STATE_ELEMENT_NOP(i, 8)
+#define GUEST_STATE_ELEMENT_NOP_W(i) \
+        GUEST_STATE_ELEMENT_NOP(i, 4)
+
+#define GUEST_STATE_ELEMENT_BASE(i, s, c) {  \
+            .id = (i),                           \
+            .size = (s),                         \
+            .location = get_vcpu_state_ptr,      \
+            .offset = 0,                         \
+            .copy = (c),                         \
+            .mask = HVMASK_DEFAULT               \
+    }
+
+#define GUEST_STATE_ELEMENT_OFF(i, s, f, c) {    \
+            .id = (i),                           \
+            .size = (s),                         \
+            .location = get_vcpu_state_ptr,      \
+            .offset = offsetof(struct nested_ppc_state, f),  \
+            .copy = (c),                         \
+            .mask = HVMASK_DEFAULT               \
+    }
+
+#define GUEST_STATE_ELEMENT_MSK(i, s, f, c, m) { \
+            .id = (i),                           \
+            .size = (s),                         \
+            .location = get_vcpu_state_ptr,      \
+            .offset = offsetof(struct nested_ppc_state, f),  \
+            .copy = (c),                         \
+            .mask = (m)                          \
+    }
+
+#define GUEST_STATE_ELEMENT_ENV_QW(i, f) \
+    GUEST_STATE_ELEMENT_OFF(i, 16, f, copy_state_16to16)
+#define GUEST_STATE_ELEMENT_ENV_DW(i, f) \
+    GUEST_STATE_ELEMENT_OFF(i, 8, f, copy_state_8to8)
+#define GUEST_STATE_ELEMENT_ENV_W(i, f) \
+    GUEST_STATE_ELEMENT_OFF(i, 4, f, copy_state_4to8)
+#define GUEST_STATE_ELEMENT_ENV_WW(i, f) \
+    GUEST_STATE_ELEMENT_OFF(i, 4, f, copy_state_4to4)
+#define GSE_ENV_DWM(i, f, m) \
+    GUEST_STATE_ELEMENT_MSK(i, 8, f, copy_state_8to8, m)
 
 /*
  * Register state for entering a nested guest with H_ENTER_NESTED.
@@ -171,16 +461,39 @@  struct nested_ppc_state {
     uint64_t sier;
     uint32_t vscr;
     uint64_t fpscr;
+    int64_t dec_expiry_tb;
+};
+
+struct SpaprMachineStateNestedGuestVcpuRunBuf {
+    uint64_t addr;
+    uint64_t size;
 };
 
 typedef struct SpaprMachineStateNestedGuestVcpu {
     bool enabled;
     struct nested_ppc_state state;
+    struct SpaprMachineStateNestedGuestVcpuRunBuf runbufin;
+    struct SpaprMachineStateNestedGuestVcpuRunBuf runbufout;
+    int64_t tb_offset;
+    uint64_t hdecr_expiry_tb;
 } SpaprMachineStateNestedGuestVcpu;
 
+struct guest_state_element_type {
+    uint16_t id;
+    int size;
+#define GUEST_STATE_ELEMENT_TYPE_FLAG_GUEST_WIDE 0x1
+#define GUEST_STATE_ELEMENT_TYPE_FLAG_READ_ONLY  0x2
+   uint16_t flags;
+    void *(*location)(SpaprMachineStateNestedGuest *, target_ulong);
+    size_t offset;
+    void (*copy)(void *, void *, bool);
+    uint64_t mask;
+};
+
 void spapr_exit_nested(PowerPCCPU *cpu, int excp);
 typedef struct SpaprMachineState SpaprMachineState;
 bool spapr_get_pate_nested_hv(SpaprMachineState *spapr, PowerPCCPU *cpu,
                               target_ulong lpid, ppc_v3_pate_t *entry);
 uint8_t spapr_nested_api(SpaprMachineState *spapr);
+void spapr_nested_gsb_init(void);
 #endif /* HW_SPAPR_NESTED_H */