tools/libxl: Set 'reg' of cpu node equal to MPIDR affinity for domU

According to ARM CPUs bindings, the reg field should match the MPIDR's
affinity bits. We will use AFF0 and AFF1 when constructing the reg value
of the guest at the moment, for it is enough for the current max vcpu
number.

Signed-off-by: Chen Baozi <baozich@gmail.com>
Reviewed-by: Julien Grall <julien.grall@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>

diff --git a/tools/libxl/libxl_arm.c b/tools/libxl/libxl_arm.c
index f09c860aa6ec3cabe114973a8a2cf6239ea4fa84..93619a57b512188a7b047b6fb612c7fbf5c31ab8 100644 (file)
--- a/tools/libxl/libxl_arm.c
+++ b/tools/libxl/libxl_arm.c
@@ -259,6 +259,7 @@ static int make_cpus_node(libxl__gc *gc, void *fdt, int nr_cpus,
                           const struct arch_info *ainfo)
 {
     int res, i;
+    uint64_t mpidr_aff;
 
     res = fdt_begin_node(fdt, "cpus");
     if (res) return res;
@@ -270,7 +271,16 @@ static int make_cpus_node(libxl__gc *gc, void *fdt, int nr_cpus,
     if (res) return res;
 
     for (i = 0; i < nr_cpus; i++) {
-        const char *name = GCSPRINTF("cpu@%d", i);
+        const char *name;
+
+        /*
+         * According to ARM CPUs bindings, the reg field should match
+         * the MPIDR's affinity bits. We will use AFF0 and AFF1 when
+         * constructing the reg value of the guest at the moment, for it
+         * is enough for the current max vcpu number.
+         */
+        mpidr_aff = (i & 0x0f) | (((i >> 4) & 0xff) << 8);
+        name = GCSPRINTF("cpu@%"PRIx64, mpidr_aff);
 
         res = fdt_begin_node(fdt, name);
         if (res) return res;
@@ -284,7 +294,7 @@ static int make_cpus_node(libxl__gc *gc, void *fdt, int nr_cpus,
         res = fdt_property_string(fdt, "enable-method", "psci");
         if (res) return res;
 
-        res = fdt_property_regs(gc, fdt, 1, 0, 1, (uint64_t)i);
+        res = fdt_property_regs(gc, fdt, 1, 0, 1, mpidr_aff);
         if (res) return res;
 
         res = fdt_end_node(fdt);