arch/mips/lib/iomap_copy.c

   1 /*
   2  * This file is free software; you can redistribute it and/or modify
   3  * it under the terms of version 2 of the GNU General Public License
   4  * as published by the Free Software Foundation.
   5  *
   6  * This program is distributed in the hope that it will be useful,
   7  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   8  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   9  * GNU General Public License for more details.
  10  *
  11  * You should have received a copy of the GNU General Public License
  12  * along with this program; if not, write to the Free Software Foundation,
  13  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
  14  */
  15
  16 #include <linux/export.h>
  17 #include <linux/io.h>
  18
  19 /**
  20  * __ioread64_copy - copy data from MMIO space, in 64-bit units
  21  * @to: destination (must be 64-bit aligned)
  22  * @from: source, in MMIO space (must be 64-bit aligned)
  23  * @count: number of 64-bit quantities to copy
  24  *
  25  * Copy data from MMIO space to kernel space, in units of 32 or 64 bits at a
  26  * time.  Order of access is not guaranteed, nor is a memory barrier
  27  * performed afterwards.
  28  */
  29 void __ioread64_copy(void *to, const void __iomem *from, size_t count)
  30 {
  31 #ifdef CONFIG_64BIT
  32         u64 *dst = to;
  33         const u64 __iomem *src = from;
  34         const u64 __iomem *end = src + count;
  35
  36         while (src < end)
  37                 *dst++ = __raw_readq(src++);
  38 #else
  39         __ioread32_copy(to, from, count * 2);
  40 #endif
  41 }
  42 EXPORT_SYMBOL_GPL(__ioread64_copy);