1/* 2 * Simple memory allocator for on-board SRAM 3 * 4 * 5 * Maintainer : Sylvain Munaut <tnt@246tNt.com> 6 * 7 * Copyright (C) 2005 Sylvain Munaut <tnt@246tNt.com> 8 * 9 * This file is licensed under the terms of the GNU General Public License 10 * version 2. This program is licensed "as is" without any warranty of any 11 * kind, whether express or implied. 12 */ 13 14#include <linux/err.h> 15#include <linux/kernel.h> 16#include <linux/module.h> 17#include <linux/slab.h> 18#include <linux/spinlock.h> 19#include <linux/string.h> 20#include <linux/ioport.h> 21#include <linux/of.h> 22 23#include <asm/io.h> 24#include <asm/mmu.h> 25 26#include "sram.h" 27 28 29/* Struct keeping our 'state' */ 30struct bcom_sram *bcom_sram = NULL; 31EXPORT_SYMBOL_GPL(bcom_sram); /* needed for inline functions */ 32 33 34/* ======================================================================== */ 35/* Public API */ 36/* ======================================================================== */ 37/* DO NOT USE in interrupts, if needed in irq handler, we should use the 38 _irqsave version of the spin_locks */ 39 40int bcom_sram_init(struct device_node *sram_node, char *owner) 41{ 42 int rv; 43 const u32 *regaddr_p; 44 u64 regaddr64, size64; 45 unsigned int psize; 46 47 /* Create our state struct */ 48 if (bcom_sram) { 49 printk(KERN_ERR "%s: bcom_sram_init: " 50 "Already initialized !\n", owner); 51 return -EBUSY; 52 } 53 54 bcom_sram = kmalloc(sizeof(struct bcom_sram), GFP_KERNEL); 55 if (!bcom_sram) { 56 printk(KERN_ERR "%s: bcom_sram_init: " 57 "Couldn't allocate internal state !\n", owner); 58 return -ENOMEM; 59 } 60 61 /* Get address and size of the sram */ 62 regaddr_p = of_get_address(sram_node, 0, &size64, NULL); 63 if (!regaddr_p) { 64 printk(KERN_ERR "%s: bcom_sram_init: " 65 "Invalid device node !\n", owner); 66 rv = -EINVAL; 67 goto error_free; 68 } 69 70 regaddr64 = of_translate_address(sram_node, regaddr_p); 71 72 bcom_sram->base_phys = (phys_addr_t) regaddr64; 73 bcom_sram->size = (unsigned int) size64; 74 75 /* Request region */ 76 if (!request_mem_region(bcom_sram->base_phys, bcom_sram->size, owner)) { 77 printk(KERN_ERR "%s: bcom_sram_init: " 78 "Couldn't request region !\n", owner); 79 rv = -EBUSY; 80 goto error_free; 81 } 82 83 /* Map SRAM */ 84 /* sram is not really __iomem */ 85 bcom_sram->base_virt = (void*) ioremap(bcom_sram->base_phys, bcom_sram->size); 86 87 if (!bcom_sram->base_virt) { 88 printk(KERN_ERR "%s: bcom_sram_init: " 89 "Map error SRAM zone 0x%08lx (0x%0x)!\n", 90 owner, (long)bcom_sram->base_phys, bcom_sram->size ); 91 rv = -ENOMEM; 92 goto error_release; 93 } 94 95 /* Create an rheap (defaults to 32 bits word alignment) */ 96 bcom_sram->rh = rh_create(4); 97 98 /* Attach the free zones */ 99 regaddr_p = NULL; 100 psize = 0; 101 102 if (!regaddr_p || !psize) { 103 /* Attach the whole zone */ 104 rh_attach_region(bcom_sram->rh, 0, bcom_sram->size); 105 } else { 106 /* Attach each zone independently */ 107 while (psize >= 2 * sizeof(u32)) { 108 phys_addr_t zbase = of_translate_address(sram_node, regaddr_p); 109 rh_attach_region(bcom_sram->rh, zbase - bcom_sram->base_phys, regaddr_p[1]); 110 regaddr_p += 2; 111 psize -= 2 * sizeof(u32); 112 } 113 } 114 115 /* Init our spinlock */ 116 spin_lock_init(&bcom_sram->lock); 117 118 return 0; 119 120error_release: 121 release_mem_region(bcom_sram->base_phys, bcom_sram->size); 122error_free: 123 kfree(bcom_sram); 124 bcom_sram = NULL; 125 126 return rv; 127} 128EXPORT_SYMBOL_GPL(bcom_sram_init); 129 130void bcom_sram_cleanup(void) 131{ 132 /* Free resources */ 133 if (bcom_sram) { 134 rh_destroy(bcom_sram->rh); 135 iounmap((void __iomem *)bcom_sram->base_virt); 136 release_mem_region(bcom_sram->base_phys, bcom_sram->size); 137 kfree(bcom_sram); 138 bcom_sram = NULL; 139 } 140} 141EXPORT_SYMBOL_GPL(bcom_sram_cleanup); 142 143void* bcom_sram_alloc(int size, int align, phys_addr_t *phys) 144{ 145 unsigned long offset; 146 147 spin_lock(&bcom_sram->lock); 148 offset = rh_alloc_align(bcom_sram->rh, size, align, NULL); 149 spin_unlock(&bcom_sram->lock); 150 151 if (IS_ERR_VALUE(offset)) 152 return NULL; 153 154 *phys = bcom_sram->base_phys + offset; 155 return bcom_sram->base_virt + offset; 156} 157EXPORT_SYMBOL_GPL(bcom_sram_alloc); 158 159void bcom_sram_free(void *ptr) 160{ 161 unsigned long offset; 162 163 if (!ptr) 164 return; 165 166 offset = ptr - bcom_sram->base_virt; 167 168 spin_lock(&bcom_sram->lock); 169 rh_free(bcom_sram->rh, offset); 170 spin_unlock(&bcom_sram->lock); 171} 172EXPORT_SYMBOL_GPL(bcom_sram_free); 173