efi: Find mirrored memory ranges for arm64

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I4SK3S
CVE: NA

--------------------------------

Mirrored memory could be used on HiSilion's arm64 SoC. So efi_find_mirror()
is added in efi_init() so that systems can get memblock about any mirrored
ranges.
Co-developed-by: NJing Xiangfeng <jingxiangfeng@huawei.com>
Signed-off-by: NMa Wupeng <mawupeng1@huawei.com>
Reviewed-by: NKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

Documentation/admin-guide/kernel-parameters.txt

@@ -1944,7 +1944,7 @@
 
 	keepinitrd	[HW,ARM]
 
-	kernelcore=	[KNL,X86,IA-64,PPC]
+	kernelcore=	[KNL,X86,IA-64,PPC,ARM64]
 			Format: nn[KMGTPE] | nn% | "mirror"
 			This parameter specifies the amount of memory usable by
 			the kernel for non-movable allocations.  The requested

arch/arm64/mm/init.c

@@ -724,8 +724,10 @@ void __init arm64_memblock_init(void)
 	else
 		arm64_dma_phys_limit = PHYS_MASK + 1;
 
-	if (efi_enabled(EFI_MEMMAP))
+	if (efi_enabled(EFI_MEMMAP)) {
 		efi_fake_memmap();
+		efi_find_mirror();
+	}
 
 	reserve_pin_memory_res();