[PATCH] riscv: fixup max_low_pfn with PFN_DOWN.

[guoren]

From: Guo Ren <ren_...@c-sky.com>

max_low_pfn should be pfn_size not byte_size.

Signed-off-by: Guo Ren <ren_...@c-sky.com>
Signed-off-by: Mao Han <mao_...@c-sky.com>
Cc: Palmer Dabbelt <pal...@sifive.com>
Cc: Albert Ou <a...@eecs.berkeley.edu>
---
 arch/riscv/kernel/setup.c | 2 +-
 arch/riscv/mm/init.c      | 3 ++-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
index fc8006a..5463e67 100644
--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -174,7 +174,7 @@ static void __init setup_bootmem(void)
        BUG_ON(mem_size == 0);
 
        set_max_mapnr(PFN_DOWN(mem_size));
-       max_low_pfn = memblock_end_of_DRAM();
+       max_low_pfn = PFN_DOWN(memblock_end_of_DRAM());
 
 #ifdef CONFIG_BLK_DEV_INITRD
        setup_initrd();
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c
index 1d9bfaf..658ebf6 100644
--- a/arch/riscv/mm/init.c
+++ b/arch/riscv/mm/init.c
@@ -28,7 +28,8 @@ static void __init zone_sizes_init(void)
        unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, };
 
 #ifdef CONFIG_ZONE_DMA32
-       max_zone_pfns[ZONE_DMA32] = PFN_DOWN(min(4UL * SZ_1G, max_low_pfn));
+       max_zone_pfns[ZONE_DMA32] = PFN_DOWN(min(4UL * SZ_1G,
+                       (unsigned long) PFN_PHYS(max_low_pfn)));
 #endif
        max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
 
-- 
2.7.4