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