diff options
| -rw-r--r-- | arch/riscv/mm/init.c | 28 |
1 files changed, 25 insertions, 3 deletions
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index 30b204546ceb..3a5190a09987 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -123,19 +123,40 @@ void __init mem_init(void) print_vm_layout(); } +/* + * The default maximal physical memory size is -PAGE_OFFSET, + * limit the memory size via mem. + */ +static phys_addr_t memory_limit = -PAGE_OFFSET; + +static int __init early_mem(char *p) +{ + u64 size; + + if (!p) + return 1; + + size = memparse(p, &p) & PAGE_MASK; + memory_limit = min_t(u64, size, memory_limit); + + pr_notice("Memory limited to %lldMB\n", (u64)memory_limit >> 20); + + return 0; +} +early_param("mem", early_mem); + static void __init setup_bootmem(void) { phys_addr_t vmlinux_end = __pa_symbol(&_end); phys_addr_t vmlinux_start = __pa_symbol(&_start); - phys_addr_t dram_end = memblock_end_of_DRAM(); phys_addr_t max_mapped_addr = __pa(~(ulong)0); + phys_addr_t dram_end; #ifdef CONFIG_XIP_KERNEL vmlinux_start = __pa_symbol(&_sdata); #endif - /* The maximal physical memory size is -PAGE_OFFSET. */ - memblock_enforce_memory_limit(-PAGE_OFFSET); + memblock_enforce_memory_limit(memory_limit); /* * Reserve from the start of the kernel to the end of the kernel @@ -150,6 +171,7 @@ static void __init setup_bootmem(void) #endif memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start); + dram_end = memblock_end_of_DRAM(); /* * memblock allocator is not aware of the fact that last 4K bytes of * the addressable memory can not be mapped because of IS_ERR_VALUE |