On Thu, Sep 17, 2020 at 04:40:55PM -0700, Atish Patra wrote: > RISC-V limits the physical memory size by -PAGE_OFFSET. Any memory beyond > that size from DRAM start is unusable. Just remove any memblock pointing > to those memory region without worrying about computing the maximum size. > > Signed-off-by: Atish Patra <[email protected]>
With one nit below Reviewed-by: Mike Rapoport <[email protected]> > --- > Changes from v1->v2: > Used memblock_enforce_memory_limit instead of memblock_remove without > computing the maximum memory size. > --- > arch/riscv/mm/init.c | 15 +++++---------- > 1 file changed, 5 insertions(+), 10 deletions(-) > > diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c > index 787c75f751a5..ed6e83871112 100644 > --- a/arch/riscv/mm/init.c > +++ b/arch/riscv/mm/init.c > @@ -146,8 +146,6 @@ static phys_addr_t dtb_early_pa __initdata; > void __init setup_bootmem(void) > { > struct memblock_region *reg; > - phys_addr_t mem_size = 0; > - phys_addr_t total_mem = 0; > phys_addr_t mem_start, end = 0; > phys_addr_t vmlinux_end = __pa_symbol(&_end); > phys_addr_t vmlinux_start = __pa_symbol(&_start); > @@ -155,21 +153,18 @@ void __init setup_bootmem(void) > /* Find the memory region containing the kernel */ > for_each_memblock(memory, reg) { > end = reg->base + reg->size; > - if (!total_mem) > + if (!mem_start) > mem_start = reg->base; > if (reg->base <= vmlinux_start && vmlinux_end <= end) > BUG_ON(reg->size == 0); > - total_mem = total_mem + reg->size; > } > > /* > - * Remove memblock from the end of usable area to the > - * end of region > + * The maximum physical memory supported is -PAGE_OFFSET. Maybe The maximal supported physical memory size is -PAGE_OFFSET > + * Make sure that any memory beyond mem_start + (-PAGE_OFFSET) is > removed > + * as it is unusable by kernel. > */ > - mem_size = min(total_mem, (phys_addr_t)-PAGE_OFFSET); > - if (mem_start + mem_size < end) > - memblock_remove(mem_start + mem_size, > - end - mem_start - mem_size); > + memblock_enforce_memory_limit(mem_start - PAGE_OFFSET); > > /* Reserve from the start of the kernel to the end of the kernel */ > memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start); > -- > 2.25.1 > -- Sincerely yours, Mike.
