target-arm: Add QOM property for Secure memory region

Add QOM property to the ARM CPU which boards can use to tell us what
memory region to use for secure accesses. Nonsecure accesses
go via the memory region specified with the base CPU class 'memory'
property.

By default, if no secure region is specified it is the same as the
nonsecure region, and if no nonsecure region is specified we will use
address_space_memory.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>

target-arm/cpu-qom.h

@@ -87,6 +87,9 @@ typedef struct ARMCPU {
     /* GPIO outputs for generic timer */
     qemu_irq gt_timer_outputs[NUM_GTIMERS];
 
+    /* MemoryRegion to use for secure physical accesses */
+    MemoryRegion *secure_memory;
+
     /* 'compatible' string for this CPU for Linux device trees */
     const char *dtb_compatible;
 

target-arm/cpu.c

@@ -543,6 +543,15 @@ static void arm_cpu_post_init(Object *obj)
          */
         qdev_property_add_static(DEVICE(obj), &arm_cpu_has_el3_property,
                                  &error_abort);
+
+#ifndef CONFIG_USER_ONLY
+        object_property_add_link(obj, "secure-memory",
+                                 TYPE_MEMORY_REGION,
+                                 (Object **)&cpu->secure_memory,
+                                 qdev_prop_allow_set_link_before_realize,
+                                 OBJ_PROP_LINK_UNREF_ON_RELEASE,
+                                 &error_abort);
+#endif
     }
 
     if (arm_feature(&cpu->env, ARM_FEATURE_MPU)) {
@@ -666,6 +675,29 @@ static void arm_cpu_realizefn(DeviceState *dev, Error **errp)
 
     init_cpreg_list(cpu);
 
+#ifndef CONFIG_USER_ONLY
+    if (cpu->has_el3) {
+        cs->num_ases = 2;
+    } else {
+        cs->num_ases = 1;
+    }
+
+    if (cpu->has_el3) {
+        AddressSpace *as;
+
+        if (!cpu->secure_memory) {
+            cpu->secure_memory = cs->memory;
+        }
+        as = address_space_init_shareable(cpu->secure_memory,
+                                          "cpu-secure-memory");
+        cpu_address_space_init(cs, as, ARMASIdx_S);
+    }
+    cpu_address_space_init(cs,
+                           address_space_init_shareable(cs->memory,
+                                                        "cpu-memory"),
+                           ARMASIdx_NS);
+#endif
+
     qemu_init_vcpu(cs);
     cpu_reset(cs);
 

target-arm/cpu.h

@@ -1720,6 +1720,12 @@ static inline int cpu_mmu_index(CPUARMState *env, bool ifetch)
     return el;
 }
 
+/* Indexes used when registering address spaces with cpu_address_space_init */
+typedef enum ARMASIdx {
+    ARMASIdx_NS = 0,
+    ARMASIdx_S = 1,
+} ARMASIdx;
+
 /* Return the Exception Level targeted by debug exceptions;
  * currently always EL1 since we don't implement EL2 or EL3.
  */