bsps/aarch64/xen: Add SMP support

bsps/aarch64/xen/include/bsp.h

@@ -71,6 +71,14 @@ extern "C" {
 
 BSP_START_TEXT_SECTION void xen_setup_mmu_and_cache( void );
 
+/**
+ * @brief Xen-specific set up of the MMU for non-primary
+ * cores.
+ *
+ * Provide in the application to override the defaults in the BSP.
+ */
+BSP_START_TEXT_SECTION void xen_setup_secondary_cpu_mmu_and_cache( void );
+
 #ifdef __cplusplus
 }
 #endif /* __cplusplus */

bsps/aarch64/xen/start/bspstarthooks.c

@@ -37,9 +37,34 @@
 #include <bsp.h>
 #include <bsp/start.h>
 
+#ifdef RTEMS_SMP
+#include <rtems/score/aarch64-system-registers.h>
+#include <rtems/score/smpimpl.h>
+
+#include <bsp/irq-generic.h>
+#endif
+
 BSP_START_TEXT_SECTION void bsp_start_hook_1( void )
 {
   AArch64_start_set_vector_base();
+
+#ifdef RTEMS_SMP
+  uint32_t cpu_index_self;
+
+  cpu_index_self = _SMP_Get_current_processor();
+
+  if ( cpu_index_self != 0 ) {
+    xen_setup_secondary_cpu_mmu_and_cache();
+    arm_gic_irq_initialize_secondary_cpu();
+
+    bsp_interrupt_vector_enable( ARM_GIC_IRQ_SGI_0 );
+    _SMP_Start_multitasking_on_secondary_processor(
+      _Per_CPU_Get_by_index( cpu_index_self )
+    );
+    /* Unreached */
+  }
+#endif /* RTEMS_SMP */
+
   xen_setup_mmu_and_cache();
   bsp_start_clear_bss();
 }

bsps/aarch64/xen/start/bspstartmmu.c

@@ -56,3 +56,12 @@ xen_setup_mmu_and_cache( void )
 
   aarch64_mmu_enable( control );
 }
+
+BSP_START_TEXT_SECTION void xen_setup_secondary_cpu_mmu_and_cache( void )
+{
+  aarch64_mmu_control *control = &aarch64_mmu_instance;
+
+  /* Perform basic MMU setup */
+  aarch64_mmu_setup();
+  aarch64_mmu_enable( control );
+}

spec/build/bsps/aarch64/xen/grp.yml

@@ -14,6 +14,8 @@ links:
   uid: abi
 - role: build-dependency
   uid: obj
+- role: build-dependency
+  uid: objsmp
 - role: build-dependency
   uid: optloadoff
 - role: build-dependency

spec/build/cpukit/optsmp.yml

@@ -21,6 +21,7 @@ enabled-by:
 - arm/realview_pbx_a9_qemu
 - arm/xilinx_zynqmp_ultra96
 - bsps/aarch64/xilinx-zynqmp
+- bsps/aarch64/xen
 - bsps/arm/xilinx-zynq
 - bsps/powerpc/qoriq
 - i386/pc586sse