[PULL 39/45] ppc/spapr: Add FWNMI System Reset state

[David Gibson <david@gibson.dropbear.id.au>]

From: Nicholas Piggin <npiggin@gmail.com>

The FWNMI option must deliver system reset interrupts to their
registered address, and there are a few constraints on the handler
addresses specified in PAPR. Add the system reset address state and
checks.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20200316142613.121089-4-npiggin@gmail.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviwed-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
 hw/ppc/spapr.c         |  2 ++
 hw/ppc/spapr_rtas.c    | 14 +++++++++++++-
 include/hw/ppc/spapr.h |  3 ++-
 3 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index 822dea8118..d22bf54baf 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -1688,6 +1688,7 @@ static void spapr_machine_reset(MachineState *machine)
 
     spapr->cas_reboot = false;
 
+    spapr->fwnmi_system_reset_addr = -1;
     spapr->fwnmi_machine_check_addr = -1;
     spapr->fwnmi_machine_check_interlock = -1;
 
@@ -2007,6 +2008,7 @@ static const VMStateDescription vmstate_spapr_fwnmi = {
     .needed = spapr_fwnmi_needed,
     .pre_save = spapr_fwnmi_pre_save,
     .fields = (VMStateField[]) {
+        VMSTATE_UINT64(fwnmi_system_reset_addr, SpaprMachineState),
         VMSTATE_UINT64(fwnmi_machine_check_addr, SpaprMachineState),
         VMSTATE_INT32(fwnmi_machine_check_interlock, SpaprMachineState),
         VMSTATE_END_OF_LIST()
diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
index 0b8c481593..521e6b0b72 100644
--- a/hw/ppc/spapr_rtas.c
+++ b/hw/ppc/spapr_rtas.c
@@ -414,6 +414,7 @@ static void rtas_ibm_nmi_register(PowerPCCPU *cpu,
                                   uint32_t nret, target_ulong rets)
 {
     hwaddr rtas_addr;
+    target_ulong sreset_addr, mce_addr;
 
     if (spapr_get_cap(spapr, SPAPR_CAP_FWNMI) == SPAPR_CAP_OFF) {
         rtas_st(rets, 0, RTAS_OUT_NOT_SUPPORTED);
@@ -426,7 +427,18 @@ static void rtas_ibm_nmi_register(PowerPCCPU *cpu,
         return;
     }
 
-    spapr->fwnmi_machine_check_addr = rtas_ld(args, 1);
+    sreset_addr = rtas_ld(args, 0);
+    mce_addr = rtas_ld(args, 1);
+
+    /* PAPR requires these are in the first 32M of memory and within RMA */
+    if (sreset_addr >= 32 * MiB || sreset_addr >= spapr->rma_size ||
+           mce_addr >= 32 * MiB ||    mce_addr >= spapr->rma_size) {
+        rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
+        return;
+    }
+
+    spapr->fwnmi_system_reset_addr = sreset_addr;
+    spapr->fwnmi_machine_check_addr = mce_addr;
 
     rtas_st(rets, 0, RTAS_OUT_SUCCESS);
 }
diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
index 64b83402cb..42d64a0368 100644
--- a/include/hw/ppc/spapr.h
+++ b/include/hw/ppc/spapr.h
@@ -194,9 +194,10 @@ struct SpaprMachineState {
 
     /* State related to FWNMI option */
 
-    /* Machine Check Notification Routine address
+    /* System Reset and Machine Check Notification Routine addresses
      * registered by "ibm,nmi-register" RTAS call.
      */
+    target_ulong fwnmi_system_reset_addr;
     target_ulong fwnmi_machine_check_addr;
 
     /* Machine Check FWNMI synchronization, fwnmi_machine_check_interlock is
-- 
2.24.1