arch/mips/loongson/common/mem.c

   1 /*
   2  * This program is free software; you can redistribute  it and/or modify it
   3  * under  the terms of  the GNU General  Public License as published by the
   4  * Free Software Foundation;  either version 2 of the  License, or (at your
   5  * option) any later version.
   6  */
   7 #include <linux/fs.h>
   8 #include <linux/fcntl.h>
   9 #include <linux/mm.h>
  10
  11 #include <asm/bootinfo.h>
  12
  13 #include <loongson.h>
  14 #include <mem.h>
  15 #include <pci.h>
  16
  17 void __init prom_init_memory(void)
  18 {
  19     add_memory_region(0x0, (memsize << 20), BOOT_MEM_RAM);
  20
  21     add_memory_region(memsize << 20, LOONGSON_PCI_MEM_START - (memsize <<
  22                             20), BOOT_MEM_RESERVED);
  23 #ifdef CONFIG_CPU_SUPPORTS_ADDRWINCFG
  24         {
  25                 int bit;
  26
  27                 bit = fls(memsize + highmemsize);
  28                 if (bit != ffs(memsize + highmemsize))
  29                         bit += 20;
  30                 else
  31                         bit = bit + 20 - 1;
  32
  33                 /* set cpu window3 to map CPU to DDR: 2G -> 2G */
  34                 LOONGSON_ADDRWIN_CPUTODDR(ADDRWIN_WIN3, 0x80000000ul,
  35                                           0x80000000ul, (1 << bit));
  36                 mmiowb();
  37         }
  38 #endif /* !CONFIG_CPU_SUPPORTS_ADDRWINCFG */
  39
  40 #ifdef CONFIG_64BIT
  41         if (highmemsize > 0)
  42                 add_memory_region(LOONGSON_HIGHMEM_START,
  43                                   highmemsize << 20, BOOT_MEM_RAM);
  44
  45         add_memory_region(LOONGSON_PCI_MEM_END + 1, LOONGSON_HIGHMEM_START -
  46                           LOONGSON_PCI_MEM_END - 1, BOOT_MEM_RESERVED);
  47
  48 #endif /* !CONFIG_64BIT */
  49 }
  50
  51 /* override of arch/mips/mm/cache.c: __uncached_access */
  52 int __uncached_access(struct file *file, unsigned long addr)
  53 {
  54         if (file->f_flags & O_DSYNC)
  55                 return 1;
  56
  57         return addr >= __pa(high_memory) ||
  58                 ((addr >= LOONGSON_MMIO_MEM_START) &&
  59                  (addr < LOONGSON_MMIO_MEM_END));
  60 }
  61
  62 #ifdef CONFIG_CPU_SUPPORTS_UNCACHED_ACCELERATED
  63
  64 #include <linux/pci.h>
  65 #include <linux/sched.h>
  66 #include <asm/current.h>
  67
  68 static unsigned long uca_start, uca_end;
  69
  70 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
  71                               unsigned long size, pgprot_t vma_prot)
  72 {
  73         unsigned long offset = pfn << PAGE_SHIFT;
  74         unsigned long end = offset + size;
  75
  76         if (__uncached_access(file, offset)) {
  77                 if (((uca_start && offset) >= uca_start) &&
  78                     (end <= uca_end))
  79                         return __pgprot((pgprot_val(vma_prot) &
  80                                          ~_CACHE_MASK) |
  81                                         _CACHE_UNCACHED_ACCELERATED);
  82                 else
  83                         return pgprot_noncached(vma_prot);
  84         }
  85         return vma_prot;
  86 }
  87
  88 static int __init find_vga_mem_init(void)
  89 {
  90         struct pci_dev *dev = 0;
  91         struct resource *r;
  92         int idx;
  93
  94         if (uca_start)
  95                 return 0;
  96
  97         for_each_pci_dev(dev) {
  98                 if ((dev->class >> 8) == PCI_CLASS_DISPLAY_VGA) {
  99                         for (idx = 0; idx < PCI_NUM_RESOURCES; idx++) {
 100                                 r = &dev->resource[idx];
 101                                 if (!r->start && r->end)
 102                                         continue;
 103                                 if (r->flags & IORESOURCE_IO)
 104                                         continue;
 105                                 if (r->flags & IORESOURCE_MEM) {
 106                                         uca_start = r->start;
 107                                         uca_end = r->end;
 108                                         return 0;
 109                                 }
 110                         }
 111                 }
 112         }
 113
 114         return 0;
 115 }
 116
 117 late_initcall(find_vga_mem_init);
 118 #endif /* !CONFIG_CPU_SUPPORTS_UNCACHED_ACCELERATED */