From 977cd7484537ba008726bf2656e877e1a971cac0 Mon Sep 17 00:00:00 2001 From: Andre Przywara Date: Wed, 14 Sep 2016 14:47:19 +0100 Subject: [PATCH] ARM: GICv3: enable LPIs on the host 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 Acked-by: Stefano Stabellini --- xen/arch/arm/gic-v3.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/xen/arch/arm/gic-v3.c b/xen/arch/arm/gic-v3.c index a559e5e260..eda3410576 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 */ -- 2.30.2