Re: [Qemu-devel] [Qemu-ppc] [PATCH 7/7] pseries: Fix XICS reset

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

On Mon, Sep 10, 2012 at 04:38:51PM +1000, David Gibson wrote:
> The XICS interrupt controller used on the pseries machine currently has no
> reset handler.  We can get away with this under some circumstances, but
> it's not correct, and can cause failures if the XICS happens to be in the
> wrong state at the time of reset.
> 
> This patch adds a hook to properly reset the XICS state.
> 
> Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

Oops, don't apply that one.  It has a bug which will break level
sensitive interrupts.  Here's a fixed version.

>From 353b529cf2049347356e3479f5e48dc2597e4fbb Mon Sep 17 00:00:00 2001
From: David Gibson <david@gibson.dropbear.id.au>
Date: Wed, 22 Aug 2012 15:20:41 +1000
Subject: [PATCH] pseries: Fix XICS reset

The XICS interrupt controller used on the pseries machine currently has no
reset handler.  We can get away with this under some circumstances, but
it's not correct, and can cause failures if the XICS happens to be in the
wrong state at the time of reset.

This patch adds a hook to properly reset the XICS state.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
 hw/xics.c |   38 ++++++++++++++++++++++++++++----------
 1 file changed, 28 insertions(+), 10 deletions(-)

diff --git a/hw/xics.c b/hw/xics.c
index b674771..a8a08ce 100644
--- a/hw/xics.c
+++ b/hw/xics.c
@@ -489,11 +489,36 @@ static void rtas_int_on(sPAPREnvironment *spapr, uint32_t token,
     rtas_st(rets, 0, 0); /* Success */
 }
 
+static void xics_reset(void *opaque)
+{
+    struct icp_state *icp = (struct icp_state *)opaque;
+    struct ics_state *ics = icp->ics;
+    int i;
+
+    for (i = 0; i < icp->nr_servers; i++) {
+        icp->ss[i].xirr = 0;
+        icp->ss[i].pending_priority = 0;
+        icp->ss[i].mfrr = 0xff;
+        /* Make all outputs are deasserted */
+        qemu_set_irq(icp->ss[i].output, 0);
+    }
+
+    for (i = 0; i < ics->nr_irqs; i++) {
+        /* Reset everything *except* the type */
+        ics->irqs[i].server = 0;
+        ics->irqs[i].asserted = 0;
+        ics->irqs[i].sent = 0;
+        ics->irqs[i].rejected = 0;
+        ics->irqs[i].masked_pending = 0;
+        ics->irqs[i].priority = 0xff;
+        ics->irqs[i].saved_priority = 0xff;
+    }
+}
+
 struct icp_state *xics_system_init(int nr_irqs)
 {
     CPUPPCState *env;
     int max_server_num;
-    int i;
     struct icp_state *icp;
     struct ics_state *ics;
 
@@ -508,10 +533,6 @@ struct icp_state *xics_system_init(int nr_irqs)
     icp->nr_servers = max_server_num + 1;
     icp->ss = g_malloc0(icp->nr_servers*sizeof(struct icp_server_state));
 
-    for (i = 0; i < icp->nr_servers; i++) {
-        icp->ss[i].mfrr = 0xff;
-    }
-
     for (env = first_cpu; env != NULL; env = env->next_cpu) {
         struct icp_server_state *ss = &icp->ss[env->cpu_index];
 
@@ -539,11 +560,6 @@ struct icp_state *xics_system_init(int nr_irqs)
     icp->ics = ics;
     ics->icp = icp;
 
-    for (i = 0; i < nr_irqs; i++) {
-        ics->irqs[i].priority = 0xff;
-        ics->irqs[i].saved_priority = 0xff;
-    }
-
     ics->qirqs = qemu_allocate_irqs(ics_set_irq, ics, nr_irqs);
 
     spapr_register_hypercall(H_CPPR, h_cppr);
@@ -556,5 +572,7 @@ struct icp_state *xics_system_init(int nr_irqs)
     spapr_rtas_register("ibm,int-off", rtas_int_off);
     spapr_rtas_register("ibm,int-on", rtas_int_on);
 
+    qemu_register_reset(xics_reset, icp);
+
     return icp;
 }
-- 
1.7.10.4



-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson