arm64: kdump: Remove custom linux,usable-memory-range handling

Remove the architecture-specific code for handling the
"linux,usable-memory-range" property under the "/chosen" node in DT, as
the platform-agnostic FDT core code already takes care of this.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/7356c531c49a24b4a55577bf8e46d93f4d8ae460.1628670468.git.geert+renesas@glider.be

arch/arm64/mm/init.c

@@ -197,45 +197,10 @@ static int __init early_mem(char *p)
 }
 early_param("mem", early_mem);
 
-static int __init early_init_dt_scan_usablemem(unsigned long node,
-		const char *uname, int depth, void *data)
-{
-	struct memblock_region *usablemem = data;
-	const __be32 *reg;
-	int len;
-
-	if (depth != 1 || strcmp(uname, "chosen") != 0)
-		return 0;
-
-	reg = of_get_flat_dt_prop(node, "linux,usable-memory-range", &len);
-	if (!reg || (len < (dt_root_addr_cells + dt_root_size_cells)))
-		return 1;
-
-	usablemem->base = dt_mem_next_cell(dt_root_addr_cells, &reg);
-	usablemem->size = dt_mem_next_cell(dt_root_size_cells, &reg);
-
-	return 1;
-}
-
-static void __init fdt_enforce_memory_region(void)
-{
-	struct memblock_region reg = {
-		.size = 0,
-	};
-
-	of_scan_flat_dt(early_init_dt_scan_usablemem, &reg);
-
-	if (reg.size)
-		memblock_cap_memory_range(reg.base, reg.size);
-}
-
 void __init arm64_memblock_init(void)
 {
 	const s64 linear_region_size = PAGE_END - _PAGE_OFFSET(vabits_actual);
 
-	/* Handle linux,usable-memory-range property */
-	fdt_enforce_memory_region();
-
 	/* Remove memory above our supported physical address size */
 	memblock_remove(1ULL << PHYS_MASK_SHIFT, ULLONG_MAX);