Introduce an abstract machine parent class which defines
the 'little_endian' property. Duplicate the current machine,
which endian is tied to the binary endianness, to one big
endian and a little endian machine; updating the machine
description. Keep the current default machine for each binary.

'petalogix-s3adsp1800' machine is aliased as:
- 'petalogix-s3adsp1800-be' on big-endian binary,
- 'petalogix-s3adsp1800-le' on little-endian one.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 hw/microblaze/petalogix_s3adsp1800_mmu.c | 55 +++++++++++++++++++++---
 1 file changed, 48 insertions(+), 7 deletions(-)

diff --git a/hw/microblaze/petalogix_s3adsp1800_mmu.c b/hw/microblaze/petalogix_s3adsp1800_mmu.c
index 8407dbee12a..f5195327b76 100644
--- a/hw/microblaze/petalogix_s3adsp1800_mmu.c
+++ b/hw/microblaze/petalogix_s3adsp1800_mmu.c
@@ -55,8 +55,17 @@
 #define ETHLITE_IRQ         1
 #define UARTLITE_IRQ        3
 
+typedef struct PetalogixS3adsp1800MachineClass {
+    MachineClass parent_obj;
+
+    bool little_endian;
+} PetalogixS3adsp1800MachineClass;
+
 #define TYPE_PETALOGIX_S3ADSP1800_MACHINE \
-            MACHINE_TYPE_NAME("petalogix-s3adsp1800")
+            MACHINE_TYPE_NAME("petalogix-s3adsp1800-common")
+DECLARE_CLASS_CHECKERS(PetalogixS3adsp1800MachineClass,
+                       PETALOGIX_S3ADSP1800_MACHINE,
+                       TYPE_PETALOGIX_S3ADSP1800_MACHINE)
 
 static void
 petalogix_s3adsp1800_init(MachineState *machine)
@@ -71,11 +80,13 @@ petalogix_s3adsp1800_init(MachineState *machine)
     MemoryRegion *phys_ram = g_new(MemoryRegion, 1);
     qemu_irq irq[32];
     MemoryRegion *sysmem = get_system_memory();
+    PetalogixS3adsp1800MachineClass *pmc;
 
+    pmc = PETALOGIX_S3ADSP1800_MACHINE_GET_CLASS(machine);
     cpu = MICROBLAZE_CPU(object_new(TYPE_MICROBLAZE_CPU));
     object_property_set_str(OBJECT(cpu), "version", "7.10.d", &error_abort);
     object_property_set_bool(OBJECT(cpu), "little-endian",
-                             !TARGET_BIG_ENDIAN, &error_abort);
+                             pmc->little_endian, &error_abort);
     qdev_realize(DEVICE(cpu), NULL, &error_abort);
 
     /* Attach emulated BRAM through the LMB.  */
@@ -123,33 +134,63 @@ petalogix_s3adsp1800_init(MachineState *machine)
     qemu_configure_nic_device(dev, true, NULL);
     qdev_prop_set_uint32(dev, "tx-ping-pong", 0);
     qdev_prop_set_uint32(dev, "rx-ping-pong", 0);
-    qdev_prop_set_bit(dev, "access-little-endian", !TARGET_BIG_ENDIAN);
+    qdev_prop_set_bit(dev, "access-little-endian", pmc->little_endian);
     sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
     sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, ETHLITE_BASEADDR);
     sysbus_connect_irq(SYS_BUS_DEVICE(dev), 0, irq[ETHLITE_IRQ]);
 
     create_unimplemented_device("xps_gpio", GPIO_BASEADDR, 0x10000);
 
-    microblaze_load_kernel(cpu, !TARGET_BIG_ENDIAN, ddr_base, ram_size,
+    microblaze_load_kernel(cpu, pmc->little_endian, ddr_base, ram_size,
                            machine->initrd_filename,
                            BINARY_DEVICE_TREE_FILE,
                            NULL);
 }
 
-static void petalogix_s3adsp1800_machine_class_init(ObjectClass *oc, void *data)
+static void petalogix_s3adsp1800_machine_class_init_be(ObjectClass *oc, void *data)
 {
     MachineClass *mc = MACHINE_CLASS(oc);
+    PetalogixS3adsp1800MachineClass *pmc = PETALOGIX_S3ADSP1800_MACHINE_CLASS(oc);
 
-    mc->desc = "PetaLogix linux refdesign for xilinx Spartan 3ADSP1800";
+    pmc->little_endian = false;
+    mc->desc = "PetaLogix linux refdesign for xilinx Spartan 3ADSP1800 (big endian)";
     mc->init = petalogix_s3adsp1800_init;
+#if TARGET_BIG_ENDIAN
     mc->is_default = true;
+    mc->alias = "petalogix-s3adsp1800";
+#endif
+}
+
+static void petalogix_s3adsp1800_machine_class_init_le(ObjectClass *oc, void *data)
+{
+    MachineClass *mc = MACHINE_CLASS(oc);
+    PetalogixS3adsp1800MachineClass *pmc = PETALOGIX_S3ADSP1800_MACHINE_CLASS(oc);
+
+    pmc->little_endian = true;
+    mc->desc = "PetaLogix linux refdesign for xilinx Spartan 3ADSP1800 (little endian)";
+    mc->init = petalogix_s3adsp1800_init;
+#if !TARGET_BIG_ENDIAN
+    mc->is_default = true;
+    mc->alias = "petalogix-s3adsp1800";
+#endif
 }
 
 static const TypeInfo petalogix_s3adsp1800_machine_types[] = {
     {
         .name           = TYPE_PETALOGIX_S3ADSP1800_MACHINE,
         .parent         = TYPE_MACHINE,
-        .class_init     = petalogix_s3adsp1800_machine_class_init,
+        .abstract       = true,
+        .class_size     = sizeof(PetalogixS3adsp1800MachineClass),
+    },
+    {
+        .name           = MACHINE_TYPE_NAME("petalogix-s3adsp1800-be"),
+        .parent         = TYPE_PETALOGIX_S3ADSP1800_MACHINE,
+        .class_init     = petalogix_s3adsp1800_machine_class_init_be,
+    },
+    {
+        .name           = MACHINE_TYPE_NAME("petalogix-s3adsp1800-le"),
+        .parent         = TYPE_PETALOGIX_S3ADSP1800_MACHINE,
+        .class_init     = petalogix_s3adsp1800_machine_class_init_le,
     },
 };
 
-- 
2.45.2

On 11/5/24 13:04, Philippe Mathieu-Daudé wrote:
> -static void petalogix_s3adsp1800_machine_class_init(ObjectClass *oc, void *data)
> +static void petalogix_s3adsp1800_machine_class_init_be(ObjectClass *oc, void *data)
>   {
>       MachineClass *mc = MACHINE_CLASS(oc);
> +    PetalogixS3adsp1800MachineClass *pmc = PETALOGIX_S3ADSP1800_MACHINE_CLASS(oc);
>   
> -    mc->desc = "PetaLogix linux refdesign for xilinx Spartan 3ADSP1800";
> +    pmc->little_endian = false;
> +    mc->desc = "PetaLogix linux refdesign for xilinx Spartan 3ADSP1800 (big endian)";
>       mc->init = petalogix_s3adsp1800_init;
> +#if TARGET_BIG_ENDIAN
>       mc->is_default = true;
> +    mc->alias = "petalogix-s3adsp1800";
> +#endif
> +}
> +
> +static void petalogix_s3adsp1800_machine_class_init_le(ObjectClass *oc, void *data)
> +{
> +    MachineClass *mc = MACHINE_CLASS(oc);
> +    PetalogixS3adsp1800MachineClass *pmc = PETALOGIX_S3ADSP1800_MACHINE_CLASS(oc);
> +
> +    pmc->little_endian = true;
> +    mc->desc = "PetaLogix linux refdesign for xilinx Spartan 3ADSP1800 (little endian)";
> +    mc->init = petalogix_s3adsp1800_init;
> +#if !TARGET_BIG_ENDIAN
> +    mc->is_default = true;
> +    mc->alias = "petalogix-s3adsp1800";
> +#endif
>   }

These can be C if's, instead of preprocessor #if, at which point you can share code.

static void petalogix_s3adsp1800_machine_class_init(ObjectClass *oc, bool little_endian)
{
     MachineClass *mc = MACHINE_CLASS(oc);
     PetalogixS3adsp1800MachineClass *pmc = PETALOGIX_S3ADSP1800_MACHINE_CLASS(oc);

     mc->init = petalogix_s3adsp1800_init;
     pmc->little_endian = little_endian;
     mc->desc = little_endian
         ? "PetaLogix linux refdesign for xilinx Spartan 3ADSP1800 (little endian)"
         : "PetaLogix linux refdesign for xilinx Spartan 3ADSP1800 (big endian)";
     if (little_endian == !TARGET_BIG_ENDIAN) {
         mc->is_default = true;
         mc->alias = "petalogix-s3adsp1800";
     }
}

static void petalogix_s3adsp1800_machine_class_init_be(ObjectClass *oc, void *data)
{
     petalogix_s3adsp1800_machine_class_init(oc, false);
}

With that,
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>


r~