xen: arm64: disable alignment traps

The mem* primitives which I am about to import from Linux in a subsequent
patch rely on the hardware handling misalignment.

The benefits of an optimised memcpy etc outweigh the downsides.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Julien Grall <julien.grall@linaro.org>
Acked-by: Tim Deegan <tim@xen.org>

diff --git a/xen/arch/arm/arm64/head.S b/xen/arch/arm/arm64/head.S
index 3077f1bb78d209fda70eb6382ec3f4b525cdcb0c..2a135274591270a016f98f291b381bdf72f96350 100644 (file)
--- a/xen/arch/arm/arm64/head.S
+++ b/xen/arch/arm/arm64/head.S
@@ -239,9 +239,9 @@ skip_bss:
          * Write-implies-XN disabled (for now),
          * D-cache disabled (for now),
          * I-cache enabled,
-         * Alignment checking enabled,
+         * Alignment checking disabled,
          * MMU translation disabled (for now). */
-        ldr   x0, =(HSCTLR_BASE|SCTLR_A)
+        ldr   x0, =(HSCTLR_BASE)
         msr   SCTLR_EL2, x0
 
         /* Rebuild the boot pagetable's first-level entries. The structure