arch/mips/loongson2ef/common/mem.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  */
   4 #include <linux/fs.h>
   5 #include <linux/fcntl.h>
   6 #include <linux/memblock.h>
   7 #include <linux/mm.h>
   8
   9 #include <asm/bootinfo.h>
  10
  11 #include <loongson.h>
  12 #include <mem.h>
  13 #include <pci.h>
  14
  15
  16 u32 memsize, highmemsize;
  17
  18 void __init prom_init_memory(void)
  19 {
  20         add_memory_region(0x0, (memsize << 20), BOOT_MEM_RAM);
  21
  22         add_memory_region(memsize << 20, LOONGSON_PCI_MEM_START - (memsize <<
  23                                 20), BOOT_MEM_RESERVED);
  24
  25 #ifdef CONFIG_CPU_SUPPORTS_ADDRWINCFG
  26         {
  27                 int bit;
  28
  29                 bit = fls(memsize + highmemsize);
  30                 if (bit != ffs(memsize + highmemsize))
  31                         bit += 20;
  32                 else
  33                         bit = bit + 20 - 1;
  34
  35                 /* set cpu window3 to map CPU to DDR: 2G -> 2G */
  36                 LOONGSON_ADDRWIN_CPUTODDR(ADDRWIN_WIN3, 0x80000000ul,
  37                                           0x80000000ul, (1 << bit));
  38                 mmiowb();
  39         }
  40 #endif /* !CONFIG_CPU_SUPPORTS_ADDRWINCFG */
  41
  42 #ifdef CONFIG_64BIT
  43         if (highmemsize > 0)
  44                 add_memory_region(LOONGSON_HIGHMEM_START,
  45                                   highmemsize << 20, BOOT_MEM_RAM);
  46
  47         add_memory_region(LOONGSON_PCI_MEM_END + 1, LOONGSON_HIGHMEM_START -
  48                           LOONGSON_PCI_MEM_END - 1, BOOT_MEM_RESERVED);
  49
  50 #endif /* !CONFIG_64BIT */
  51 }
  52
  53 /* override of arch/mips/mm/cache.c: __uncached_access */
  54 int __uncached_access(struct file *file, unsigned long addr)
  55 {
  56         if (file->f_flags & O_DSYNC)
  57                 return 1;
  58
  59         return addr >= __pa(high_memory) ||
  60                 ((addr >= LOONGSON_MMIO_MEM_START) &&
  61                  (addr < LOONGSON_MMIO_MEM_END));
  62 }