csky: simplify detection of memory zone boundaries

The free_area_init() function only requires the definition of maximal PFN
for each of the supported zone rater than calculation of actual zone sizes
and the sizes of the holes between the zones.

After removal of CONFIG_HAVE_MEMBLOCK_NODE_MAP the free_area_init() is
available to all architectures.

Using this function instead of free_area_init_node() simplifies the zone
detection.

Signed-off-by: Mike Rapoport <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Tested-by: Hoan Tran <[email protected]>	[arm64]
Cc: Baoquan He <[email protected]>
Cc: Brian Cain <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Greentime Hu <[email protected]>
Cc: Greg Ungerer <[email protected]>
Cc: Guan Xuetao <[email protected]>
Cc: Guo Ren <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Helge Deller <[email protected]>
Cc: "James E.J. Bottomley" <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Cc: Ley Foon Tan <[email protected]>
Cc: Mark Salter <[email protected]>
Cc: Matt Turner <[email protected]>
Cc: Max Filippov <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Michal Simek <[email protected]>
Cc: Nick Hu <[email protected]>
Cc: Paul Walmsley <[email protected]>
Cc: Richard Weinberger <[email protected]>
Cc: Rich Felker <[email protected]>
Cc: Russell King <[email protected]>
Cc: Stafford Horne <[email protected]>
Cc: Thomas Bogendoerfer <[email protected]>
Cc: Tony Luck <[email protected]>
Cc: Vineet Gupta <[email protected]>
Cc: Yoshinori Sato <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>

1 files changed, 11 insertions, 15 deletions

diff --git a/arch/csky/kernel/setup.c b/arch/csky/kernel/setup.c
index 819a9a7bf786..0481f4e34538 100644
--- a/arch/csky/kernel/setup.c
+++ b/arch/csky/kernel/setup.c
@@ -26,7 +26,9 @@ struct screen_info screen_info = {
 
 static void __init csky_memblock_init(void)
 {
-	unsigned long zone_size[MAX_NR_ZONES];
+	unsigned long lowmem_size = PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET);
+	unsigned long sseg_size = PFN_DOWN(SSEG_SIZE - PHYS_OFFSET_OFFSET);
+	unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0 };
 	signed long size;
 
 	memblock_reserve(__pa(_stext), _end - _stext);
@@ -36,28 +38,22 @@ static void __init csky_memblock_init(void)
 
 	memblock_dump_all();
 
-	memset(zone_size, 0, sizeof(zone_size));
-
 	min_low_pfn = PFN_UP(memblock_start_of_DRAM());
 	max_low_pfn = max_pfn = PFN_DOWN(memblock_end_of_DRAM());
 
 	size = max_pfn - min_low_pfn;
 
-	if (size <= PFN_DOWN(SSEG_SIZE - PHYS_OFFSET_OFFSET))
-		zone_size[ZONE_NORMAL] = size;
-	else if (size < PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET)) {
-		zone_size[ZONE_NORMAL] =
-				PFN_DOWN(SSEG_SIZE - PHYS_OFFSET_OFFSET);
-		max_low_pfn = min_low_pfn + zone_size[ZONE_NORMAL];
-	} else {
-		zone_size[ZONE_NORMAL] =
-				PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET);
-		max_low_pfn = min_low_pfn + zone_size[ZONE_NORMAL];
+	if (size >= lowmem_size) {
+		max_low_pfn = min_low_pfn + lowmem_size;
 		write_mmu_msa1(read_mmu_msa0() + SSEG_SIZE);
+	} else if (size > sseg_size) {
+		max_low_pfn = min_low_pfn + sseg_size;
 	}
 
+	max_zone_pfn[ZONE_NORMAL] = max_low_pfn;
+
 #ifdef CONFIG_HIGHMEM
-	zone_size[ZONE_HIGHMEM] = max_pfn - max_low_pfn;
+	max_zone_pfn[ZONE_HIGHMEM] = max_pfn;
 
 	highstart_pfn = max_low_pfn;
 	highend_pfn   = max_pfn;
@@ -66,7 +62,7 @@ static void __init csky_memblock_init(void)
 
 	dma_contiguous_reserve(0);
 
-	free_area_init_node(0, zone_size, min_low_pfn, NULL);
+	free_area_init(max_zone_pfn);
 }
 
 void __init setup_arch(char **cmdline_p)