[PATCH v7 12/17] ARM64: ACPI: Check if it runs on Xen to enable or disable ACPI

Shannon Zhao
2016-03-24T14:48:12Z

When it's a Xen domain0 booting with ACPI, it will supply a /chosen and
a /hypervisor node in DT. So check if it needs to enable ACPI.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Hanjun Guo <hanjun.guo@linaro.org>
---
arch/arm64/kernel/acpi.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c
index d1ce8e2..4e92be0 100644
--- a/arch/arm64/kernel/acpi.c
+++ b/arch/arm64/kernel/acpi.c
@@ -67,10 +67,13 @@ static int __init dt_scan_depth1_nodes(unsigned long node,
{
/*
* Return 1 as soon as we encounter a node at depth 1 that is
- * not the /chosen node.
+ * not the /chosen node, or /hypervisor node when running on Xen.
*/
- if (depth == 1 && (strcmp(uname, "chosen") != 0))
- return 1;
+ if (depth == 1 && (strcmp(uname, "chosen") != 0)) {
+ if (!xen_initial_domain() || (strcmp(uname, "hypervisor") != 0))
+ return 1;
+ }
+
return 0;
}

@@ -184,7 +187,8 @@ void __init acpi_boot_table_init(void)
/*
* Enable ACPI instead of device tree unless
* - ACPI has been disabled explicitly (acpi=off), or
- * - the device tree is not empty (it has more than just a /chosen node)
+ * - the device tree is not empty (it has more than just a /chosen node,
+ * and a /hypervisor node when running on Xen)
* and ACPI has not been force enabled (acpi=force)
*/
if (param_acpi_off ||
--
2.1.4