arch/ia64/mm/contig.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 1998-2003 Hewlett-Packard Co
   7  *      David Mosberger-Tang <davidm@hpl.hp.com>
   8  *      Stephane Eranian <eranian@hpl.hp.com>
   9  * Copyright (C) 2000, Rohit Seth <rohit.seth@intel.com>
  10  * Copyright (C) 1999 VA Linux Systems
  11  * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
  12  * Copyright (C) 2003 Silicon Graphics, Inc. All rights reserved.
  13  *
  14  * Routines used by ia64 machines with contiguous (or virtually contiguous)
  15  * memory.
  16  */
  17 #include <linux/efi.h>
  18 #include <linux/memblock.h>
  19 #include <linux/mm.h>
  20 #include <linux/nmi.h>
  21 #include <linux/swap.h>
  22 #include <linux/sizes.h>
  23
  24 #include <asm/efi.h>
  25 #include <asm/meminit.h>
  26 #include <asm/sections.h>
  27 #include <asm/mca.h>
  28
  29 /* physical address where the bootmem map is located */
  30 unsigned long bootmap_start;
  31
  32 #ifdef CONFIG_SMP
  33 static void *cpu_data;
  34 /**
  35  * per_cpu_init - setup per-cpu variables
  36  *
  37  * Allocate and setup per-cpu data areas.
  38  */
  39 void *per_cpu_init(void)
  40 {
  41         static bool first_time = true;
  42         void *cpu0_data = __cpu0_per_cpu;
  43         unsigned int cpu;
  44
  45         if (!first_time)
  46                 goto skip;
  47         first_time = false;
  48
  49         /*
  50          * get_free_pages() cannot be used before cpu_init() done.
  51          * BSP allocates PERCPU_PAGE_SIZE bytes for all possible CPUs
  52          * to avoid that AP calls get_zeroed_page().
  53          */
  54         for_each_possible_cpu(cpu) {
  55                 void *src = cpu == 0 ? cpu0_data : __phys_per_cpu_start;
  56
  57                 memcpy(cpu_data, src, __per_cpu_end - __per_cpu_start);
  58                 __per_cpu_offset[cpu] = (char *)cpu_data - __per_cpu_start;
  59                 per_cpu(local_per_cpu_offset, cpu) = __per_cpu_offset[cpu];
  60
  61                 /*
  62                  * percpu area for cpu0 is moved from the __init area
  63                  * which is setup by head.S and used till this point.
  64                  * Update ar.k3.  This move is ensures that percpu
  65                  * area for cpu0 is on the correct node and its
  66                  * virtual address isn't insanely far from other
  67                  * percpu areas which is important for congruent
  68                  * percpu allocator.
  69                  */
  70                 if (cpu == 0)
  71                         ia64_set_kr(IA64_KR_PER_CPU_DATA, __pa(cpu_data) -
  72                                     (unsigned long)__per_cpu_start);
  73
  74                 cpu_data += PERCPU_PAGE_SIZE;
  75         }
  76 skip:
  77         return __per_cpu_start + __per_cpu_offset[smp_processor_id()];
  78 }
  79
  80 static inline void
  81 alloc_per_cpu_data(void)
  82 {
  83         size_t size = PERCPU_PAGE_SIZE * num_possible_cpus();
  84
  85         cpu_data = memblock_alloc_from(size, PERCPU_PAGE_SIZE,
  86                                        __pa(MAX_DMA_ADDRESS));
  87         if (!cpu_data)
  88                 panic("%s: Failed to allocate %lu bytes align=%lx from=%lx\n",
  89                       __func__, size, PERCPU_PAGE_SIZE, __pa(MAX_DMA_ADDRESS));
  90 }
  91
  92 /**
  93  * setup_per_cpu_areas - setup percpu areas
  94  *
  95  * Arch code has already allocated and initialized percpu areas.  All
  96  * this function has to do is to teach the determined layout to the
  97  * dynamic percpu allocator, which happens to be more complex than
  98  * creating whole new ones using helpers.
  99  */
 100 void __init
 101 setup_per_cpu_areas(void)
 102 {
 103         struct pcpu_alloc_info *ai;
 104         struct pcpu_group_info *gi;
 105         unsigned int cpu;
 106         ssize_t static_size, reserved_size, dyn_size;
 107
 108         ai = pcpu_alloc_alloc_info(1, num_possible_cpus());
 109         if (!ai)
 110                 panic("failed to allocate pcpu_alloc_info");
 111         gi = &ai->groups[0];
 112
 113         /* units are assigned consecutively to possible cpus */
 114         for_each_possible_cpu(cpu)
 115                 gi->cpu_map[gi->nr_units++] = cpu;
 116
 117         /* set parameters */
 118         static_size = __per_cpu_end - __per_cpu_start;
 119         reserved_size = PERCPU_MODULE_RESERVE;
 120         dyn_size = PERCPU_PAGE_SIZE - static_size - reserved_size;
 121         if (dyn_size < 0)
 122                 panic("percpu area overflow static=%zd reserved=%zd\n",
 123                       static_size, reserved_size);
 124
 125         ai->static_size         = static_size;
 126         ai->reserved_size       = reserved_size;
 127         ai->dyn_size            = dyn_size;
 128         ai->unit_size           = PERCPU_PAGE_SIZE;
 129         ai->atom_size           = PAGE_SIZE;
 130         ai->alloc_size          = PERCPU_PAGE_SIZE;
 131
 132         pcpu_setup_first_chunk(ai, __per_cpu_start + __per_cpu_offset[0]);
 133         pcpu_free_alloc_info(ai);
 134 }
 135 #else
 136 #define alloc_per_cpu_data() do { } while (0)
 137 #endif /* CONFIG_SMP */
 138
 139 /**
 140  * find_memory - setup memory map
 141  *
 142  * Walk the EFI memory map and find usable memory for the system, taking
 143  * into account reserved areas.
 144  */
 145 void __init
 146 find_memory (void)
 147 {
 148         reserve_memory();
 149
 150         /* first find highest page frame number */
 151         min_low_pfn = ~0UL;
 152         max_low_pfn = 0;
 153         efi_memmap_walk(find_max_min_low_pfn, NULL);
 154         max_pfn = max_low_pfn;
 155
 156         memblock_add_node(0, PFN_PHYS(max_low_pfn), 0);
 157
 158         find_initrd();
 159
 160         alloc_per_cpu_data();
 161 }
 162
 163 static int __init find_largest_hole(u64 start, u64 end, void *arg)
 164 {
 165         u64 *max_gap = arg;
 166
 167         static u64 last_end = PAGE_OFFSET;
 168
 169         /* NOTE: this algorithm assumes efi memmap table is ordered */
 170
 171         if (*max_gap < (start - last_end))
 172                 *max_gap = start - last_end;
 173         last_end = end;
 174         return 0;
 175 }
 176
 177 static void __init verify_gap_absence(void)
 178 {
 179         unsigned long max_gap;
 180
 181         /* Forbid FLATMEM if hole is > than 1G */
 182         efi_memmap_walk(find_largest_hole, (u64 *)&max_gap);
 183         if (max_gap >= SZ_1G)
 184                 panic("Cannot use FLATMEM with %ldMB hole\n"
 185                       "Please switch over to SPARSEMEM\n",
 186                       (max_gap >> 20));
 187 }
 188
 189 /*
 190  * Set up the page tables.
 191  */
 192
 193 void __init
 194 paging_init (void)
 195 {
 196         unsigned long max_dma;
 197         unsigned long max_zone_pfns[MAX_NR_ZONES];
 198
 199         memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
 200         max_dma = virt_to_phys((void *) MAX_DMA_ADDRESS) >> PAGE_SHIFT;
 201         max_zone_pfns[ZONE_DMA32] = max_dma;
 202         max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
 203
 204         verify_gap_absence();
 205
 206         free_area_init(max_zone_pfns);
 207         zero_page_memmap_ptr = virt_to_page(ia64_imva(empty_zero_page));
 208 }