arch/m68k/amiga/chipram.c

   1 /*
   2 **  linux/amiga/chipram.c
   3 **
   4 **      Modified 03-May-94 by Geert Uytterhoeven <geert@linux-m68k.org>
   5 **          - 64-bit aligned allocations for full AGA compatibility
   6 **
   7 **      Rewritten 15/9/2000 by Geert to use resource management
   8 */
   9
  10 #include <linux/types.h>
  11 #include <linux/kernel.h>
  12 #include <linux/mm.h>
  13 #include <linux/init.h>
  14 #include <linux/ioport.h>
  15 #include <linux/slab.h>
  16 #include <linux/string.h>
  17 #include <linux/module.h>
  18
  19 #include <asm/page.h>
  20 #include <asm/amigahw.h>
  21
  22 unsigned long amiga_chip_size;
  23 EXPORT_SYMBOL(amiga_chip_size);
  24
  25 static struct resource chipram_res = {
  26     .name = "Chip RAM", .start = CHIP_PHYSADDR
  27 };
  28 static unsigned long chipavail;
  29
  30
  31 void __init amiga_chip_init(void)
  32 {
  33     if (!AMIGAHW_PRESENT(CHIP_RAM))
  34         return;
  35
  36     /*
  37      *  Remove the first 4 pages where PPC exception handlers will be located
  38      */
  39     amiga_chip_size -= 0x4000;
  40     chipram_res.end = amiga_chip_size-1;
  41     request_resource(&iomem_resource, &chipram_res);
  42
  43     chipavail = amiga_chip_size;
  44 }
  45
  46
  47 void *amiga_chip_alloc(unsigned long size, const char *name)
  48 {
  49     struct resource *res;
  50
  51     /* round up */
  52     size = PAGE_ALIGN(size);
  53
  54 #ifdef DEBUG
  55     printk("amiga_chip_alloc: allocate %ld bytes\n", size);
  56 #endif
  57     res = kzalloc(sizeof(struct resource), GFP_KERNEL);
  58     if (!res)
  59         return NULL;
  60     res->name = name;
  61
  62     if (allocate_resource(&chipram_res, res, size, 0, UINT_MAX, PAGE_SIZE, NULL, NULL) < 0) {
  63         kfree(res);
  64         return NULL;
  65     }
  66     chipavail -= size;
  67 #ifdef DEBUG
  68     printk("amiga_chip_alloc: returning %lx\n", res->start);
  69 #endif
  70     return (void *)ZTWO_VADDR(res->start);
  71 }
  72 EXPORT_SYMBOL(amiga_chip_alloc);
  73
  74
  75     /*
  76      *  Warning:
  77      *  amiga_chip_alloc_res is meant only for drivers that need to allocate
  78      *  Chip RAM before kmalloc() is functional. As a consequence, those
  79      *  drivers must not free that Chip RAM afterwards.
  80      */
  81
  82 void * __init amiga_chip_alloc_res(unsigned long size, struct resource *res)
  83 {
  84     unsigned long start;
  85
  86     /* round up */
  87     size = PAGE_ALIGN(size);
  88     /* dmesg into chipmem prefers memory at the safe end */
  89     start = CHIP_PHYSADDR + chipavail - size;
  90
  91 #ifdef DEBUG
  92     printk("amiga_chip_alloc_res: allocate %ld bytes\n", size);
  93 #endif
  94     if (allocate_resource(&chipram_res, res, size, start, UINT_MAX, PAGE_SIZE, NULL, NULL) < 0) {
  95         printk("amiga_chip_alloc_res: first alloc failed!\n");
  96         if (allocate_resource(&chipram_res, res, size, 0, UINT_MAX, PAGE_SIZE, NULL, NULL) < 0)
  97             return NULL;
  98     }
  99     chipavail -= size;
 100 #ifdef DEBUG
 101     printk("amiga_chip_alloc_res: returning %lx\n", res->start);
 102 #endif
 103     return (void *)ZTWO_VADDR(res->start);
 104 }
 105
 106 void amiga_chip_free(void *ptr)
 107 {
 108     unsigned long start = ZTWO_PADDR(ptr);
 109     struct resource **p, *res;
 110     unsigned long size;
 111
 112     for (p = &chipram_res.child; (res = *p); p = &res->sibling) {
 113         if (res->start != start)
 114             continue;
 115         *p = res->sibling;
 116         size = res->end-start;
 117 #ifdef DEBUG
 118         printk("amiga_chip_free: free %ld bytes at %p\n", size, ptr);
 119 #endif
 120         chipavail += size;
 121         kfree(res);
 122         return;
 123     }
 124     printk("amiga_chip_free: trying to free nonexistent region at %p\n", ptr);
 125 }
 126 EXPORT_SYMBOL(amiga_chip_free);
 127
 128
 129 unsigned long amiga_chip_avail(void)
 130 {
 131 #ifdef DEBUG
 132         printk("amiga_chip_avail : %ld bytes\n", chipavail);
 133 #endif
 134         return chipavail;
 135 }
 136 EXPORT_SYMBOL(amiga_chip_avail);
 137