riscv: Covert to reserve_initrd_mem()

Covert to the generic reserve_initrd_mem() function.
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

arch/riscv/mm/init.c

@@ -106,55 +106,6 @@ void __init mem_init(void)
 	print_vm_layout();
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-static void __init setup_initrd(void)
-{
-	phys_addr_t start;
-	unsigned long size;
-
-	/* Ignore the virtul address computed during device tree parsing */
-	initrd_start = initrd_end = 0;
-
-	if (!phys_initrd_size)
-		return;
-	/*
-	 * Round the memory region to page boundaries as per free_initrd_mem()
-	 * This allows us to detect whether the pages overlapping the initrd
-	 * are in use, but more importantly, reserves the entire set of pages
-	 * as we don't want these pages allocated for other purposes.
-	 */
-	start = round_down(phys_initrd_start, PAGE_SIZE);
-	size = phys_initrd_size + (phys_initrd_start - start);
-	size = round_up(size, PAGE_SIZE);
-
-	if (!memblock_is_region_memory(start, size)) {
-		pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region",
-		       (u64)start, size);
-		goto disable;
-	}
-
-	if (memblock_is_region_reserved(start, size)) {
-		pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region\n",
-		       (u64)start, size);
-		goto disable;
-	}
-
-	memblock_reserve(start, size);
-	/* Now convert initrd to virtual addresses */
-	initrd_start = (unsigned long)__va(phys_initrd_start);
-	initrd_end = initrd_start + phys_initrd_size;
-	initrd_below_start_ok = 1;
-
-	pr_info("Initial ramdisk at: 0x%p (%lu bytes)\n",
-		(void *)(initrd_start), size);
-	return;
-disable:
-	pr_cont(" - disabling initrd\n");
-	initrd_start = 0;
-	initrd_end = 0;
-}
-#endif /* CONFIG_BLK_DEV_INITRD */
-
 void __init setup_bootmem(void)
 {
 	phys_addr_t mem_start = 0;
@@ -187,10 +138,7 @@ void __init setup_bootmem(void)
 	dma32_phys_limit = min(4UL * SZ_1G, (unsigned long)PFN_PHYS(max_low_pfn));
 	set_max_mapnr(max_low_pfn);
 
-#ifdef CONFIG_BLK_DEV_INITRD
-	setup_initrd();
-#endif /* CONFIG_BLK_DEV_INITRD */
-
+	reserve_initrd_mem();
 	/*
 	 * If DTB is built in, no need to reserve its memblock.
 	 * Otherwise, do reserve it but avoid using