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authorAnup Patel <anup.patel@wdc.com>2022-02-04 23:16:40 +0530
committerAlistair Francis <alistair.francis@wdc.com>2022-02-16 12:24:18 +1000
commit02d9565b92c97af6bac2ff1bb18967a5e95b9694 (patch)
treea8fa240303e2707d7a981ba9c9f6000fb78262f6 /target/riscv
parentcd032fe75c1f7b24ccad772d50bfb689e7f5835d (diff)
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target/riscv: Improve delivery of guest external interrupts
The guest external interrupts from an interrupt controller are delivered only when the Guest/VM is running (i.e. V=1). This means any guest external interrupt which is triggered while the Guest/VM is not running (i.e. V=0) will be missed on QEMU resulting in Guest with sluggish response to serial console input and other I/O events. To solve this, we check and inject interrupt after setting V=1. Signed-off-by: Anup Patel <anup.patel@wdc.com> Signed-off-by: Anup Patel <anup@brainfault.org> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Frank Chang <frank.chang@sifive.com> Message-id: 20220204174700.534953-5-anup@brainfault.org Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Diffstat (limited to 'target/riscv')
-rw-r--r--target/riscv/cpu_helper.c13
1 files changed, 13 insertions, 0 deletions
diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c
index 698389b..e45ca08 100644
--- a/target/riscv/cpu_helper.c
+++ b/target/riscv/cpu_helper.c
@@ -326,6 +326,19 @@ void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable)
}
env->virt = set_field(env->virt, VIRT_ONOFF, enable);
+
+ if (enable) {
+ /*
+ * The guest external interrupts from an interrupt controller are
+ * delivered only when the Guest/VM is running (i.e. V=1). This means
+ * any guest external interrupt which is triggered while the Guest/VM
+ * is not running (i.e. V=0) will be missed on QEMU resulting in guest
+ * with sluggish response to serial console input and other I/O events.
+ *
+ * To solve this, we check and inject interrupt after setting V=1.
+ */
+ riscv_cpu_update_mip(env_archcpu(env), 0, 0);
+ }
}
bool riscv_cpu_two_stage_lookup(int mmu_idx)