[Qemu-devel] [PATCH v8 6/8] register: Add block initialise helper

[Alistair Francis]

From: Peter Crosthwaite <address@hidden>

Add a helper that will scan a static RegisterAccessInfo Array
and populate a container MemoryRegion with registers as defined.

Signed-off-by: Peter Crosthwaite <address@hidden>
Signed-off-by: Alistair Francis <address@hidden>
---
The reason that I'm not using GArray is because the array needs to store
the memory region that covers all of the registers.

V8:
 - Add a finalise function used to free the allocated memory
V7:
 - Return the memory region instead of adding it as a subregion
V6:
 - Fixup the loop logic
V5:
 - Convert to only using one memory region
V3:
 - Fix typo
V2:
 - Use memory_region_add_subregion_no_print()

 hw/core/register.c    | 44 ++++++++++++++++++++++++++++++++++++++++++++
 include/hw/register.h | 36 ++++++++++++++++++++++++++++++++++++
 2 files changed, 80 insertions(+)

diff --git a/hw/core/register.c b/hw/core/register.c
index 058c998..7b73bf4 100644
--- a/hw/core/register.c
+++ b/hw/core/register.c
@@ -228,6 +228,50 @@ uint64_t register_read_memory(void *opaque, hwaddr addr,
     return extract64(read_val, 0, size * 8);
 }
 
+RegisterInfoArray *register_init_block32(DeviceState *owner,
+                                         const RegisterAccessInfo *rae,
+                                         int num, RegisterInfo *ri,
+                                         uint32_t *data,
+                                         const MemoryRegionOps *ops,
+                                         bool debug_enabled,
+                                         uint64_t memory_size)
+{
+    const char *device_prefix = object_get_typename(OBJECT(owner));
+    RegisterInfoArray *r_array = g_new0(RegisterInfoArray, 1);
+    int i;
+
+    r_array->r = g_new0(RegisterInfo *, num);
+    r_array->num_elements = num;
+    r_array->debug = debug_enabled;
+    r_array->prefix = device_prefix;
+
+    for (i = 0; i < num; i++) {
+        int index = rae[i].addr / 4;
+        RegisterInfo *r = &ri[index];
+
+        *r = (RegisterInfo) {
+            .data = &data[index],
+            .data_size = sizeof(uint32_t),
+            .access = &rae[i],
+            .opaque = owner,
+        };
+        register_init(r);
+
+        r_array->r[i] = r;
+    }
+
+    memory_region_init_io(&r_array->mem, OBJECT(owner), ops, r_array,
+                          device_prefix, memory_size);
+
+    return r_array;
+}
+
+void register_finlise_block(RegisterInfoArray *r_array)
+{
+    g_free(r_array->r);
+    g_free(r_array);
+}
+
 static const TypeInfo register_info = {
     .name  = TYPE_REGISTER,
     .parent = TYPE_DEVICE,
diff --git a/include/hw/register.h b/include/hw/register.h
index 61c53fb..b8d464d 100644
--- a/include/hw/register.h
+++ b/include/hw/register.h
@@ -100,6 +100,8 @@ struct RegisterInfo {
  */
 
 struct RegisterInfoArray {
+    MemoryRegion mem;
+
     int num_elements;
     RegisterInfo **r;
 
@@ -166,6 +168,40 @@ void register_write_memory(void *opaque, hwaddr addr, 
uint64_t value,
 
 uint64_t register_read_memory(void *opaque, hwaddr addr, unsigned size);
 
+/**
+ * Init a block of registers into a container MemoryRegion. A
+ * number of constant register definitions are parsed to create a corresponding
+ * array of RegisterInfo's.
+ *
+ * @owner: device owning the registers
+ * @rae: Register definitions to init
+ * @num: number of registers to init (length of @rae)
+ * @ri: Register array to init, must already be allocated
+ * @data: Array to use for register data, must already be allocated
+ * @ops: Memory region ops to access registers.
+ * @debug enabled: turn on/off verbose debug information
+ * returns: An structure containing all of the registers and an initialized
+            memory region (r_array->mem) the caller should add to a container.
+ */
+
+RegisterInfoArray *register_init_block32(DeviceState *owner,
+                                         const RegisterAccessInfo *rae,
+                                         int num, RegisterInfo *ri,
+                                         uint32_t *data,
+                                         const MemoryRegionOps *ops,
+                                         bool debug_enabled,
+                                         uint64_t memory_size);
+
+/**
+ * This function should be called to cleanup the registers that were 
initialized
+ * when calling register_init_block32()
+ *
+ * @r_array: An structure containing all of the registers. The caller is in
+ *           charge of cleaning up the memory region (r_array->mem).
+ */
+
+void register_finlise_block(RegisterInfoArray *r_array);
+
 /* Define constants for a 32 bit register */
 
 /* This macro will define A_FOO, for the byte address of a register
-- 
2.7.4