diff options
Diffstat (limited to 'arch/arc/mm/init.c')
| -rw-r--r-- | arch/arc/mm/init.c | 32 |
1 files changed, 15 insertions, 17 deletions
diff --git a/arch/arc/mm/init.c b/arch/arc/mm/init.c index 33832e36bdb7..abfeef7bf6f8 100644 --- a/arch/arc/mm/init.c +++ b/arch/arc/mm/init.c @@ -32,11 +32,6 @@ unsigned long arch_pfn_offset; EXPORT_SYMBOL(arch_pfn_offset); #endif -#ifdef CONFIG_DISCONTIGMEM -struct pglist_data node_data[MAX_NUMNODES] __read_mostly; -EXPORT_SYMBOL(node_data); -#endif - long __init arc_get_mem_sz(void) { return low_mem_sz; @@ -139,25 +134,28 @@ void __init setup_arch_memory(void) #ifdef CONFIG_HIGHMEM /* - * Populate a new node with highmem - * * On ARC (w/o PAE) HIGHMEM addresses are actually smaller (0 based) - * than addresses in normal ala low memory (0x8000_0000 based). + * than addresses in normal aka low memory (0x8000_0000 based). * Even with PAE, the huge peripheral space hole would waste a lot of - * mem with single mem_map[]. This warrants a mem_map per region design. - * Thus HIGHMEM on ARC is imlemented with DISCONTIGMEM. - * - * DISCONTIGMEM in turns requires multiple nodes. node 0 above is - * populated with normal memory zone while node 1 only has highmem + * mem with single contiguous mem_map[]. + * Thus when HIGHMEM on ARC is enabled the memory map corresponding + * to the hole is freed and ARC specific version of pfn_valid() + * handles the hole in the memory map. */ -#ifdef CONFIG_DISCONTIGMEM - node_set_online(1); -#endif min_high_pfn = PFN_DOWN(high_mem_start); max_high_pfn = PFN_DOWN(high_mem_start + high_mem_sz); - max_zone_pfn[ZONE_HIGHMEM] = min_low_pfn; + /* + * max_high_pfn should be ok here for both HIGHMEM and HIGHMEM+PAE. + * For HIGHMEM without PAE max_high_pfn should be less than + * min_low_pfn to guarantee that these two regions don't overlap. + * For PAE case highmem is greater than lowmem, so it is natural + * to use max_high_pfn. + * + * In both cases, holes should be handled by pfn_valid(). + */ + max_zone_pfn[ZONE_HIGHMEM] = max_high_pfn; high_memory = (void *)(min_high_pfn << PAGE_SHIFT); |