1 /* 2 * (c) Copyright 2006 Benjamin Herrenschmidt, IBM Corp. 3 * <benh@kernel.crashing.org> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License as published by 7 * the Free Software Foundation; either version 2 of the License, or 8 * (at your option) any later version. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See 13 * the GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 18 */ 19 20 #undef DEBUG 21 22 #include <linux/kernel.h> 23 #include <asm/prom.h> 24 #include <asm/dcr.h> 25 26 unsigned int dcr_resource_start(struct device_node *np, unsigned int index) 27 { 28 unsigned int ds; 29 const u32 *dr = of_get_property(np, "dcr-reg", &ds); 30 31 if (dr == NULL || ds & 1 || index >= (ds / 8)) 32 return 0; 33 34 return dr[index * 2]; 35 } 36 37 unsigned int dcr_resource_len(struct device_node *np, unsigned int index) 38 { 39 unsigned int ds; 40 const u32 *dr = of_get_property(np, "dcr-reg", &ds); 41 42 if (dr == NULL || ds & 1 || index >= (ds / 8)) 43 return 0; 44 45 return dr[index * 2 + 1]; 46 } 47 48 #ifndef CONFIG_PPC_DCR_NATIVE 49 50 static struct device_node * find_dcr_parent(struct device_node * node) 51 { 52 struct device_node *par, *tmp; 53 const u32 *p; 54 55 for (par = of_node_get(node); par;) { 56 if (of_get_property(par, "dcr-controller", NULL)) 57 break; 58 p = of_get_property(par, "dcr-parent", NULL); 59 tmp = par; 60 if (p == NULL) 61 par = of_get_parent(par); 62 else 63 par = of_find_node_by_phandle(*p); 64 of_node_put(tmp); 65 } 66 return par; 67 } 68 69 u64 of_translate_dcr_address(struct device_node *dev, 70 unsigned int dcr_n, 71 unsigned int *out_stride) 72 { 73 struct device_node *dp; 74 const u32 *p; 75 unsigned int stride; 76 u64 ret; 77 78 dp = find_dcr_parent(dev); 79 if (dp == NULL) 80 return OF_BAD_ADDR; 81 82 /* Stride is not properly defined yet, default to 0x10 for Axon */ 83 p = of_get_property(dp, "dcr-mmio-stride", NULL); 84 stride = (p == NULL) ? 0x10 : *p; 85 86 /* XXX FIXME: Which property name is to use of the 2 following ? */ 87 p = of_get_property(dp, "dcr-mmio-range", NULL); 88 if (p == NULL) 89 p = of_get_property(dp, "dcr-mmio-space", NULL); 90 if (p == NULL) 91 return OF_BAD_ADDR; 92 93 /* Maybe could do some better range checking here */ 94 ret = of_translate_address(dp, p); 95 if (ret != OF_BAD_ADDR) 96 ret += (u64)(stride) * (u64)dcr_n; 97 if (out_stride) 98 *out_stride = stride; 99 return ret; 100 } 101 102 dcr_host_t dcr_map(struct device_node *dev, unsigned int dcr_n, 103 unsigned int dcr_c) 104 { 105 dcr_host_t ret = { .token = NULL, .stride = 0 }; 106 u64 addr; 107 108 pr_debug("dcr_map(%s, 0x%x, 0x%x)\n", 109 dev->full_name, dcr_n, dcr_c); 110 111 addr = of_translate_dcr_address(dev, dcr_n, &ret.stride); 112 pr_debug("translates to addr: 0x%lx, stride: 0x%x\n", 113 addr, ret.stride); 114 if (addr == OF_BAD_ADDR) 115 return ret; 116 pr_debug("mapping 0x%x bytes\n", dcr_c * ret.stride); 117 ret.token = ioremap(addr, dcr_c * ret.stride); 118 if (ret.token == NULL) 119 return ret; 120 pr_debug("mapped at 0x%p -> base is 0x%p\n", 121 ret.token, ret.token - dcr_n * ret.stride); 122 ret.token -= dcr_n * ret.stride; 123 return ret; 124 } 125 126 void dcr_unmap(dcr_host_t host, unsigned int dcr_n, unsigned int dcr_c) 127 { 128 dcr_host_t h = host; 129 130 if (h.token == NULL) 131 return; 132 h.token += dcr_n * h.stride; 133 iounmap(h.token); 134 h.token = NULL; 135 } 136 137 #endif /* !defined(CONFIG_PPC_DCR_NATIVE) */ 138