1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Simple memory allocator for on-board SRAM 4 * 5 * Maintainer : Sylvain Munaut <tnt@246tNt.com> 6 * 7 * Copyright (C) 2005 Sylvain Munaut <tnt@246tNt.com> 8 */ 9 10 #include <linux/err.h> 11 #include <linux/kernel.h> 12 #include <linux/export.h> 13 #include <linux/slab.h> 14 #include <linux/spinlock.h> 15 #include <linux/string.h> 16 #include <linux/ioport.h> 17 #include <linux/of.h> 18 #include <linux/of_address.h> 19 20 #include <asm/io.h> 21 #include <asm/mmu.h> 22 23 #include <linux/fsl/bestcomm/sram.h> 24 25 26 /* Struct keeping our 'state' */ 27 struct bcom_sram *bcom_sram = NULL; 28 EXPORT_SYMBOL_GPL(bcom_sram); /* needed for inline functions */ 29 30 31 /* ======================================================================== */ 32 /* Public API */ 33 /* ======================================================================== */ 34 /* DO NOT USE in interrupts, if needed in irq handler, we should use the 35 _irqsave version of the spin_locks */ 36 37 int bcom_sram_init(struct device_node *sram_node, char *owner) 38 { 39 int rv; 40 const u32 *regaddr_p; 41 struct resource res; 42 unsigned int psize; 43 44 /* Create our state struct */ 45 if (bcom_sram) { 46 printk(KERN_ERR "%s: bcom_sram_init: " 47 "Already initialized !\n", owner); 48 return -EBUSY; 49 } 50 51 bcom_sram = kmalloc(sizeof(struct bcom_sram), GFP_KERNEL); 52 if (!bcom_sram) { 53 printk(KERN_ERR "%s: bcom_sram_init: " 54 "Couldn't allocate internal state !\n", owner); 55 return -ENOMEM; 56 } 57 58 /* Get address and size of the sram */ 59 rv = of_address_to_resource(sram_node, 0, &res); 60 if (rv) { 61 printk(KERN_ERR "%s: bcom_sram_init: " 62 "Invalid device node !\n", owner); 63 goto error_free; 64 } 65 66 bcom_sram->base_phys = res.start; 67 bcom_sram->size = resource_size(&res); 68 69 /* Request region */ 70 if (!request_mem_region(res.start, resource_size(&res), owner)) { 71 printk(KERN_ERR "%s: bcom_sram_init: " 72 "Couldn't request region !\n", owner); 73 rv = -EBUSY; 74 goto error_free; 75 } 76 77 /* Map SRAM */ 78 /* sram is not really __iomem */ 79 bcom_sram->base_virt = (void *)ioremap(res.start, resource_size(&res)); 80 81 if (!bcom_sram->base_virt) { 82 printk(KERN_ERR "%s: bcom_sram_init: " 83 "Map error SRAM zone 0x%08lx (0x%0x)!\n", 84 owner, (long)bcom_sram->base_phys, bcom_sram->size ); 85 rv = -ENOMEM; 86 goto error_release; 87 } 88 89 /* Create an rheap (defaults to 32 bits word alignment) */ 90 bcom_sram->rh = rh_create(4); 91 92 /* Attach the free zones */ 93 #if 0 94 /* Currently disabled ... for future use only */ 95 reg_addr_p = of_get_property(sram_node, "available", &psize); 96 #else 97 regaddr_p = NULL; 98 psize = 0; 99 #endif 100 101 if (!regaddr_p || !psize) { 102 /* Attach the whole zone */ 103 rh_attach_region(bcom_sram->rh, 0, bcom_sram->size); 104 } else { 105 /* Attach each zone independently */ 106 while (psize >= 2 * sizeof(u32)) { 107 phys_addr_t zbase = of_translate_address(sram_node, regaddr_p); 108 rh_attach_region(bcom_sram->rh, zbase - bcom_sram->base_phys, regaddr_p[1]); 109 regaddr_p += 2; 110 psize -= 2 * sizeof(u32); 111 } 112 } 113 114 /* Init our spinlock */ 115 spin_lock_init(&bcom_sram->lock); 116 117 return 0; 118 119 error_release: 120 release_mem_region(res.start, resource_size(&res)); 121 error_free: 122 kfree(bcom_sram); 123 bcom_sram = NULL; 124 125 return rv; 126 } 127 EXPORT_SYMBOL_GPL(bcom_sram_init); 128 129 void bcom_sram_cleanup(void) 130 { 131 /* Free resources */ 132 if (bcom_sram) { 133 rh_destroy(bcom_sram->rh); 134 iounmap((void __iomem *)bcom_sram->base_virt); 135 release_mem_region(bcom_sram->base_phys, bcom_sram->size); 136 kfree(bcom_sram); 137 bcom_sram = NULL; 138 } 139 } 140 EXPORT_SYMBOL_GPL(bcom_sram_cleanup); 141 142 void* bcom_sram_alloc(int size, int align, phys_addr_t *phys) 143 { 144 unsigned long offset; 145 146 spin_lock(&bcom_sram->lock); 147 offset = rh_alloc_align(bcom_sram->rh, size, align, NULL); 148 spin_unlock(&bcom_sram->lock); 149 150 if (IS_ERR_VALUE(offset)) 151 return NULL; 152 153 *phys = bcom_sram->base_phys + offset; 154 return bcom_sram->base_virt + offset; 155 } 156 EXPORT_SYMBOL_GPL(bcom_sram_alloc); 157 158 void bcom_sram_free(void *ptr) 159 { 160 unsigned long offset; 161 162 if (!ptr) 163 return; 164 165 offset = ptr - bcom_sram->base_virt; 166 167 spin_lock(&bcom_sram->lock); 168 rh_free(bcom_sram->rh, offset); 169 spin_unlock(&bcom_sram->lock); 170 } 171 EXPORT_SYMBOL_GPL(bcom_sram_free); 172