[Blackfin] arch: add code to initialize globals declared in linux/bootmem.h: max_pfn...

Signed-off-by: Yi Li <yi.li@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>

diff --git a/arch/blackfin/kernel/setup.c b/arch/blackfin/kernel/setup.c
index 2255c28..a871d83 100644 (file)
--- a/arch/blackfin/kernel/setup.c
+++ b/arch/blackfin/kernel/setup.c
@@ -547,11 +547,38 @@ static __init void  memory_setup(void)
                );
 }
 
+/*
+ * Find the lowest, highest page frame number we have available
+ */
+void __init find_min_max_pfn(void)
+{
+       int i;
+
+       max_pfn = 0;
+       min_low_pfn = memory_end;
+
+       for (i = 0; i < bfin_memmap.nr_map; i++) {
+               unsigned long start, end;
+               /* RAM? */
+               if (bfin_memmap.map[i].type != BFIN_MEMMAP_RAM)
+                       continue;
+               start = PFN_UP(bfin_memmap.map[i].addr);
+               end = PFN_DOWN(bfin_memmap.map[i].addr +
+                               bfin_memmap.map[i].size);
+               if (start >= end)
+                       continue;
+               if (end > max_pfn)
+                       max_pfn = end;
+               if (start < min_low_pfn)
+                       min_low_pfn = start;
+       }
+}
+
 static __init void setup_bootmem_allocator(void)
 {
        int bootmap_size;
        int i;
-       unsigned long min_pfn, max_pfn;
+       unsigned long start_pfn, end_pfn;
        unsigned long curr_pfn, last_pfn, size;
 
        /* mark memory between memory_start and memory_end usable */
@@ -561,8 +588,19 @@ static __init void setup_bootmem_allocator(void)
        sanitize_memmap(bfin_memmap.map, &bfin_memmap.nr_map);
        print_memory_map("boot memmap");
 
-       min_pfn = PAGE_OFFSET >> PAGE_SHIFT;
-       max_pfn = memory_end >> PAGE_SHIFT;
+       /* intialize globals in linux/bootmem.h */
+       find_min_max_pfn();
+       /* pfn of the last usable page frame */
+       if (max_pfn > memory_end >> PAGE_SHIFT)
+               max_pfn = memory_end >> PAGE_SHIFT;
+       /* pfn of last page frame directly mapped by kernel */
+       max_low_pfn = max_pfn;
+       /* pfn of the first usable page frame after kernel image*/
+       if (min_low_pfn < memory_start >> PAGE_SHIFT)
+               min_low_pfn = memory_start >> PAGE_SHIFT;
+
+       start_pfn = PAGE_OFFSET >> PAGE_SHIFT;
+       end_pfn = memory_end >> PAGE_SHIFT;
 
        /*
         * give all the memory to the bootmap allocator,  tell it to put the
@@ -570,7 +608,7 @@ static __init void setup_bootmem_allocator(void)
         */
        bootmap_size = init_bootmem_node(NODE_DATA(0),
                        memory_start >> PAGE_SHIFT,     /* map goes here */
-                       min_pfn, max_pfn);
+                       start_pfn, end_pfn);
 
        /* register the memmap regions with the bootmem allocator */
        for (i = 0; i < bfin_memmap.nr_map; i++) {
@@ -583,7 +621,7 @@ static __init void setup_bootmem_allocator(void)
                 * We are rounding up the start address of usable memory:
                 */
                curr_pfn = PFN_UP(bfin_memmap.map[i].addr);
-               if (curr_pfn >= max_pfn)
+               if (curr_pfn >= end_pfn)
                        continue;
                /*
                 * ... and at the end of the usable range downwards:
@@ -591,8 +629,8 @@ static __init void setup_bootmem_allocator(void)
                last_pfn = PFN_DOWN(bfin_memmap.map[i].addr +
                                         bfin_memmap.map[i].size);
 
-               if (last_pfn > max_pfn)
-                       last_pfn = max_pfn;
+               if (last_pfn > end_pfn)
+                       last_pfn = end_pfn;
 
                /*
                 * .. finally, did all the rounding and playing