[Blackfin] arch: fix bug kernel boot message: memory information is not reasonable

Some of the information in kernel boot message is not reasonable.
http://blackfin.uclinux.org/gf/project/uclinux-dist/tracker/?action=TrackerItemEdit&tracker_item_id=3846

 - use _rambase as the start of kernel image.
   kernel is in the region [_rambase, _ramstart]
 - count in pages in per-cpu-page list as available memory
 - reserved memory now include: [0 - 4K] for bad pointer catching,
   memory reserved for abnormaly 05000263, memory reserved by kernel itself.

Signed-off-by: Yi Li <yi.li@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>

1 files changed, 23 insertions, 6 deletions

diff --git a/arch/blackfin/mm/init.c b/arch/blackfin/mm/init.c
index 9f007cace6e6..eb1a12ac9e33 100644
--- a/arch/blackfin/mm/init.c
+++ b/arch/blackfin/mm/init.c
@@ -128,8 +128,8 @@ void __init paging_init(void)
 void __init mem_init(void)
 {
         unsigned int codek = 0, datak = 0, initk = 0;
+        unsigned int reservedpages = 0, freepages = 0;
         unsigned long tmp;
-        unsigned int len = _ramend - _rambase;
         unsigned long start_mem = memory_start;
         unsigned long end_mem = memory_end;
 
@@ -138,19 +138,36 @@ void __init mem_init(void)
 
         start_mem = PAGE_ALIGN(start_mem);
         max_mapnr = num_physpages = MAP_NR(high_memory);
-        printk(KERN_INFO "Physical pages: %lx\n", num_physpages);
+        printk(KERN_INFO "Kernel managed physical pages: %lu\n",
+                num_physpages);
 
         /* This will put all memory onto the freelists. */
         totalram_pages = free_all_bootmem();
 
+        reservedpages = 0;
+        for (tmp = 0; tmp < max_mapnr; tmp++)
+                if (PageReserved(pfn_to_page(tmp)))
+                        reservedpages++;
+        freepages =  max_mapnr - reservedpages;
+
+        /* do not count in kernel image between _rambase and _ramstart */
+        reservedpages -= (_ramstart - _rambase) >> PAGE_SHIFT;
+#if (defined(CONFIG_BFIN_ICACHE) && ANOMALY_05000263)
+        reservedpages += (_ramend - memory_end - DMA_UNCACHED_REGION) >>
+                                PAGE_SHIFT;
+#endif
+
         codek = (_etext - _stext) >> 10;
-        datak = (__bss_stop - __bss_start) >> 10;
         initk = (__init_end - __init_begin) >> 10;
+        datak = ((_ramstart - _rambase) >> 10) - codek - initk;
 
-        tmp = nr_free_pages() << PAGE_SHIFT;
         printk(KERN_INFO
-             "Memory available: %luk/%uk RAM, (%uk init code, %uk kernel code, %uk data, %uk dma)\n",
-             tmp >> 10, len >> 10, initk, codek, datak, DMA_UNCACHED_REGION >> 10);
+             "Memory available: %luk/%luk RAM, "
+                "(%uk init code, %uk kernel code, "
+                "%uk data, %uk dma, %uk reserved)\n",
+                (unsigned long) freepages << (PAGE_SHIFT-10), _ramend >> 10,
+                initk, codek, datak, DMA_UNCACHED_REGION >> 10,
+                (reservedpages << (PAGE_SHIFT-10)));
 
         /* Initialize the blackfin L1 Memory. */
         l1sram_init();