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
  24 #ifdef CONFIG_CPU_SUPPORTS_ADDRWINCFG
  25         {
  26                 int bit;
  27
  28                 bit = fls(memsize + highmemsize);
  29                 if (bit != ffs(memsize + highmemsize))
  30                         bit += 20;
  31                 else
  32                         bit = bit + 20 - 1;
  33
  34                 /* set cpu window3 to map CPU to DDR: 2G -> 2G */
  35                 LOONGSON_ADDRWIN_CPUTODDR(ADDRWIN_WIN3, 0x80000000ul,
  36                                           0x80000000ul, (1 << bit));
  37                 mmiowb();
  38         }
  39 #endif /* !CONFIG_CPU_SUPPORTS_ADDRWINCFG */
  40
  41 #ifdef CONFIG_64BIT
  42         if (highmemsize > 0)
  43                 add_memory_region(LOONGSON_HIGHMEM_START,
  44                                   highmemsize << 20, BOOT_MEM_RAM);
  45
  46         add_memory_region(LOONGSON_PCI_MEM_END + 1, LOONGSON_HIGHMEM_START -
  47                           LOONGSON_PCI_MEM_END - 1, BOOT_MEM_RESERVED);
  48
  49 #endif /* !CONFIG_64BIT */
  50 }
  51
  52 /* override of arch/mips/mm/cache.c: __uncached_access */
  53 int __uncached_access(struct file *file, unsigned long addr)
  54 {
  55         if (file->f_flags & O_DSYNC)
  56                 return 1;
  57
  58         return addr >= __pa(high_memory) ||
  59                 ((addr >= LOONGSON_MMIO_MEM_START) &&
  60                  (addr < LOONGSON_MMIO_MEM_END));
  61 }
  62
  63 #ifdef CONFIG_CPU_SUPPORTS_UNCACHED_ACCELERATED
  64
  65 #include <linux/pci.h>
  66 #include <linux/sched.h>
  67 #include <asm/current.h>
  68
  69 static unsigned long uca_start, uca_end;
  70
  71 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
  72                               unsigned long size, pgprot_t vma_prot)
  73 {
  74         unsigned long offset = pfn << PAGE_SHIFT;
  75         unsigned long end = offset + size;
  76
  77         if (__uncached_access(file, offset)) {
  78                 if (uca_start && (offset >= uca_start) &&
  79                     (end <= uca_end))
  80                         return __pgprot((pgprot_val(vma_prot) &
  81                                          ~_CACHE_MASK) |
  82                                         _CACHE_UNCACHED_ACCELERATED);
  83                 else
  84                         return pgprot_noncached(vma_prot);
  85         }
  86         return vma_prot;
  87 }
  88
  89 static int __init find_vga_mem_init(void)
  90 {
  91         struct pci_dev *dev = 0;
  92         struct resource *r;
  93         int idx;
  94
  95         if (uca_start)
  96                 return 0;
  97
  98         for_each_pci_dev(dev) {
  99                 if ((dev->class >> 16) == PCI_BASE_CLASS_DISPLAY) {
 100                         for (idx = 0; idx < PCI_NUM_RESOURCES; idx++) {
 101                                 r = &dev->resource[idx];
 102                                 if (!r->start && r->end)
 103                                         continue;
 104                                 if (r->flags & IORESOURCE_IO)
 105                                         continue;
 106                                 if (r->flags & IORESOURCE_MEM) {
 107                                         uca_start = r->start;
 108                                         uca_end = r->end;
 109                                         return 0;
 110                                 }
 111                         }
 112                 }
 113         }
 114
 115         return 0;
 116 }
 117
 118 late_initcall(find_vga_mem_init);
 119 #endif /* !CONFIG_CPU_SUPPORTS_UNCACHED_ACCELERATED */