1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 ** linux/amiga/chipram.c 4 ** 5 ** Modified 03-May-94 by Geert Uytterhoeven <geert@linux-m68k.org> 6 ** - 64-bit aligned allocations for full AGA compatibility 7 ** 8 ** Rewritten 15/9/2000 by Geert to use resource management 9 */ 10 11 #include <linux/types.h> 12 #include <linux/kernel.h> 13 #include <linux/mm.h> 14 #include <linux/init.h> 15 #include <linux/ioport.h> 16 #include <linux/slab.h> 17 #include <linux/string.h> 18 #include <linux/module.h> 19 20 #include <asm/atomic.h> 21 #include <asm/page.h> 22 #include <asm/amigahw.h> 23 24 unsigned long amiga_chip_size; 25 EXPORT_SYMBOL(amiga_chip_size); 26 27 static struct resource chipram_res = { 28 .name = "Chip RAM", .start = CHIP_PHYSADDR 29 }; 30 static atomic_t chipavail; 31 32 33 void __init amiga_chip_init(void) 34 { 35 if (!AMIGAHW_PRESENT(CHIP_RAM)) 36 return; 37 38 chipram_res.end = CHIP_PHYSADDR + amiga_chip_size - 1; 39 request_resource(&iomem_resource, &chipram_res); 40 41 atomic_set(&chipavail, amiga_chip_size); 42 } 43 44 45 void *amiga_chip_alloc(unsigned long size, const char *name) 46 { 47 struct resource *res; 48 void *p; 49 50 res = kzalloc(sizeof(struct resource), GFP_KERNEL); 51 if (!res) 52 return NULL; 53 54 res->name = name; 55 p = amiga_chip_alloc_res(size, res); 56 if (!p) { 57 kfree(res); 58 return NULL; 59 } 60 61 return p; 62 } 63 EXPORT_SYMBOL(amiga_chip_alloc); 64 65 66 /* 67 * Warning: 68 * amiga_chip_alloc_res is meant only for drivers that need to 69 * allocate Chip RAM before kmalloc() is functional. As a consequence, 70 * those drivers must not free that Chip RAM afterwards. 71 */ 72 73 void *amiga_chip_alloc_res(unsigned long size, struct resource *res) 74 { 75 int error; 76 77 /* round up */ 78 size = PAGE_ALIGN(size); 79 80 pr_debug("amiga_chip_alloc_res: allocate %lu bytes\n", size); 81 error = allocate_resource(&chipram_res, res, size, 0, UINT_MAX, 82 PAGE_SIZE, NULL, NULL); 83 if (error < 0) { 84 pr_err("amiga_chip_alloc_res: allocate_resource() failed %d!\n", 85 error); 86 return NULL; 87 } 88 89 atomic_sub(size, &chipavail); 90 pr_debug("amiga_chip_alloc_res: returning %pR\n", res); 91 return ZTWO_VADDR(res->start); 92 } 93 94 void amiga_chip_free(void *ptr) 95 { 96 unsigned long start = ZTWO_PADDR(ptr); 97 struct resource *res; 98 unsigned long size; 99 100 res = lookup_resource(&chipram_res, start); 101 if (!res) { 102 pr_err("amiga_chip_free: trying to free nonexistent region at " 103 "%p\n", ptr); 104 return; 105 } 106 107 size = resource_size(res); 108 pr_debug("amiga_chip_free: free %lu bytes at %p\n", size, ptr); 109 atomic_add(size, &chipavail); 110 release_resource(res); 111 kfree(res); 112 } 113 EXPORT_SYMBOL(amiga_chip_free); 114 115 116 unsigned long amiga_chip_avail(void) 117 { 118 unsigned long n = atomic_read(&chipavail); 119 120 pr_debug("amiga_chip_avail : %lu bytes\n", n); 121 return n; 122 } 123 EXPORT_SYMBOL(amiga_chip_avail); 124 125