PPC: e500: require libfdt

Now that we're moving all of the device tree generation from an external
pre-execution generated blob to runtime generation using libfdt, we absolutely
must have libfdt around.

This requirement was there before already, as the only way to not require libfdt
with e500 was to not use -kernel, which was the only way to boot the mpc8544ds
machine. This patch only manifests said requirement in the build system.

Signed-off-by: Alexander Graf <agraf@suse.de>

hw/ppc/Makefile.objs

@@ -15,7 +15,7 @@ obj-$(CONFIG_PSERIES) += spapr_pci.o pci-hotplug.o
 obj-y += ppc4xx_devs.o ppc4xx_pci.o ppc405_uc.o ppc405_boards.o
 obj-y += ppc440_bamboo.o
 # PowerPC E500 boards
-obj-y += ppce500_mpc8544ds.o mpc8544_guts.o ppce500_spin.o
+obj-$(CONFIG_FDT) += ppce500_mpc8544ds.o mpc8544_guts.o ppce500_spin.o
 # PowerPC 440 Xilinx ML507 reference board.
 obj-y += virtex_ml507.o
 # PowerPC OpenPIC

hw/ppce500_mpc8544ds.c

@@ -68,7 +68,6 @@ static int mpc8544_load_device_tree(CPUPPCState *env,
                                     const char *kernel_cmdline)
 {
     int ret = -1;
-#ifdef CONFIG_FDT
     uint32_t mem_reg_property[] = {0, cpu_to_be32(ramsize)};
     char *filename;
     int fdt_size;
@@ -173,7 +172,6 @@ static int mpc8544_load_device_tree(CPUPPCState *env,
     ret = fdt_size;
 
 out:
-#endif
 
     return ret;
 }
@@ -391,9 +389,6 @@ static void mpc8544ds_init(ram_addr_t ram_size,
         struct boot_info *boot_info;
         int dt_size;
 
-#ifndef CONFIG_FDT
-        cpu_abort(env, "Compiled without FDT support - can't load kernel\n");
-#endif
         dt_base = (loadaddr + kernel_size + DTC_LOAD_PAD) & ~DTC_PAD_MASK;
         dt_size = mpc8544_load_device_tree(env, dt_base, ram_size, initrd_base,
                                            initrd_size, kernel_cmdline);