From: Andre Przywara Date: Wed, 19 Apr 2017 16:30:49 +0000 (+0100) Subject: ARM: GICv3: enable ITS on the host X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=bde03c44b1d368edcdace8cdfef56cba3211411c;p=people%2Froyger%2Fxen.git ARM: GICv3: enable ITS on the host Even though the ITS emulation is not yet in place, the host ITS already gets initialized and Xen tries to map the host collections. However for commands to be processed we need to *enable* the ITS, which will be done in a later patch not yet merged. So those MAPC commands are not processed and run into a timeout, leading to a panic on machines which advertise an ITS in their DT. This patch just enables the ITS (but not the LPIs on each redistributor), to get those MAPC commands executed. This fixes booting Xen on ARM64 machines with an ITS and the (EXPERT) ITS Kconfig option enabled. Signed-off-by: Andre Przywara Acked-by: Julien Grall Acked-by: Stefano Stabellini --- diff --git a/xen/arch/arm/gic-v3-its.c b/xen/arch/arm/gic-v3-its.c index 07280b305d..aebc257f0d 100644 --- a/xen/arch/arm/gic-v3-its.c +++ b/xen/arch/arm/gic-v3-its.c @@ -505,6 +505,10 @@ static int gicv3_its_init_single_its(struct host_its *hw_its) return -ENOMEM; writeq_relaxed(0, hw_its->its_base + GITS_CWRITER); + /* Now enable interrupt translation and command processing on that ITS. */ + reg = readl_relaxed(hw_its->its_base + GITS_CTLR); + writel_relaxed(reg | GITS_CTLR_ENABLE, hw_its->its_base + GITS_CTLR); + return 0; }