diff mbox

[v11,03/34] ARM: GICv3: enable LPIs on the host

Message ID 20170609174141.5068-4-andre.przywara@arm.com (mailing list archive)
State New, archived
Headers show

Commit Message

Andre Przywara June 9, 2017, 5:41 p.m. UTC 
Now that the host part of the ITS code is in place, we can enable the
LPIs on each redistributor to get the show rolling.
At this point there would be no LPIs mapped, as guests don't know about
the ITS yet.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
---
 xen/arch/arm/gic-v3.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)
diff mbox

Patch

diff --git a/xen/arch/arm/gic-v3.c b/xen/arch/arm/gic-v3.c
index a559e5e..eda3410 100644
--- a/xen/arch/arm/gic-v3.c
+++ b/xen/arch/arm/gic-v3.c
@@ -620,6 +620,21 @@  static int gicv3_enable_redist(void)
     return 0;
 }
 
+/* Enable LPIs on this redistributor (only useful when the host has an ITS). */
+static bool gicv3_enable_lpis(void)
+{
+    uint32_t val;
+
+    val = readl_relaxed(GICD_RDIST_BASE + GICR_TYPER);
+    if ( !(val & GICR_TYPER_PLPIS) )
+        return false;
+
+    val = readl_relaxed(GICD_RDIST_BASE + GICR_CTLR);
+    writel_relaxed(val | GICR_CTLR_ENABLE_LPIS, GICD_RDIST_BASE + GICR_CTLR);
+
+    return true;
+}
+
 static int __init gicv3_populate_rdist(void)
 {
     int i;
@@ -731,11 +746,14 @@  static int gicv3_cpu_init(void)
     if ( gicv3_enable_redist() )
         return -ENODEV;
 
+    /* If the host has any ITSes, enable LPIs now. */
     if ( gicv3_its_host_has_its() )
     {
         ret = gicv3_its_setup_collection(smp_processor_id());
         if ( ret )
             return ret;
+        if ( !gicv3_enable_lpis() )
+            return -EBUSY;
     }
 
     /* Set priority on PPI and SGI interrupts */