ARM: sort the meminfo array earlier

The meminfo array has to be sorted before sanity_check_meminfo() in
arch/arm/mm/mmu.c is called for it to work properly.  This also allows
for a simpler find_limits() in arch/arm/mm/init.c.

The sort is moved to arch/arm/kernel/setup.c because that's where the
meminfo array is populated.  Eventually this should be improved upon
to make the memory bank parser a bit more robust against problems
such as overlapping memory ranges.

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>

1 files changed, 8 insertions, 30 deletions

diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c
index fbdd12ea3a58..d366051e14fe 100644
--- a/arch/arm/mm/init.c
+++ b/arch/arm/mm/init.c
@@ -20,7 +20,6 @@
 #include <linux/highmem.h>
 #include <linux/gfp.h>
 #include <linux/memblock.h>
-#include <linux/sort.h>
 
 #include <asm/mach-types.h>
 #include <asm/prom.h>
@@ -134,30 +133,18 @@ void show_mem(unsigned int filter)
 }
 
 static void __init find_limits(unsigned long *min, unsigned long *max_low,
-        unsigned long *max_high)
+                               unsigned long *max_high)
 {
         struct meminfo *mi = &meminfo;
         int i;
 
-        *min = -1UL;
-        *max_low = *max_high = 0;
-
-        for_each_bank (i, mi) {
-                struct membank *bank = &mi->bank[i];
-                unsigned long start, end;
-
-                start = bank_pfn_start(bank);
-                end = bank_pfn_end(bank);
-
-                if (*min > start)
-                        *min = start;
-                if (*max_high < end)
-                        *max_high = end;
-                if (bank->highmem)
-                        continue;
-                if (*max_low < end)
-                        *max_low = end;
-        }
+        /* This assumes the meminfo array is properly sorted */
+        *min = bank_pfn_start(&mi->bank[0]);
+        for_each_bank (i, mi)
+                if (mi->bank[i].highmem)
+                                break;
+        *max_low = bank_pfn_end(&mi->bank[i - 1]);
+        *max_high = bank_pfn_end(&mi->bank[mi->nr_banks - 1]);
 }
 
 static void __init arm_bootmem_init(unsigned long start_pfn,
@@ -319,19 +306,10 @@ static void arm_memory_present(void)
 }
 #endif
 
-static int __init meminfo_cmp(const void *_a, const void *_b)
-{
-        const struct membank *a = _a, *b = _b;
-        long cmp = bank_pfn_start(a) - bank_pfn_start(b);
-        return cmp < 0 ? -1 : cmp > 0 ? 1 : 0;
-}
-
 void __init arm_memblock_init(struct meminfo *mi, struct machine_desc *mdesc)
 {
         int i;
 
-        sort(&meminfo.bank, meminfo.nr_banks, sizeof(meminfo.bank[0]), meminfo_cmp, NULL);
-
         memblock_init();
         for (i = 0; i < mi->nr_banks; i++)
                 memblock_add(mi->bank[i].start, mi->bank[i].size);