1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * A hack to create a platform device from a DMI entry. This will 4 * allow autoloading of the IPMI drive based on SMBIOS entries. 5 */ 6 7 #include <linux/ipmi.h> 8 #include <linux/init.h> 9 #include <linux/dmi.h> 10 #include <linux/platform_device.h> 11 #include <linux/property.h> 12 #include "ipmi_si_sm.h" 13 #include "ipmi_dmi.h" 14 15 #define IPMI_DMI_TYPE_KCS 0x01 16 #define IPMI_DMI_TYPE_SMIC 0x02 17 #define IPMI_DMI_TYPE_BT 0x03 18 #define IPMI_DMI_TYPE_SSIF 0x04 19 20 struct ipmi_dmi_info { 21 enum si_type si_type; 22 u32 flags; 23 unsigned long addr; 24 u8 slave_addr; 25 struct ipmi_dmi_info *next; 26 }; 27 28 static struct ipmi_dmi_info *ipmi_dmi_infos; 29 30 static int ipmi_dmi_nr __initdata; 31 32 #define set_prop_entry(_p_, _name_, type, val) \ 33 do { \ 34 struct property_entry *_p = &_p_; \ 35 _p->name = _name_; \ 36 _p->length = sizeof(type); \ 37 _p->is_string = false; \ 38 _p->value.type##_data = val; \ 39 } while(0) 40 41 static void __init dmi_add_platform_ipmi(unsigned long base_addr, 42 u32 flags, 43 u8 slave_addr, 44 int irq, 45 int offset, 46 int type) 47 { 48 struct platform_device *pdev; 49 struct resource r[4]; 50 unsigned int num_r = 1, size; 51 struct property_entry p[5]; 52 unsigned int pidx = 0; 53 char *name, *override; 54 int rv; 55 enum si_type si_type; 56 struct ipmi_dmi_info *info; 57 58 memset(p, 0, sizeof(p)); 59 60 name = "dmi-ipmi-si"; 61 override = "ipmi_si"; 62 switch (type) { 63 case IPMI_DMI_TYPE_SSIF: 64 name = "dmi-ipmi-ssif"; 65 override = "ipmi_ssif"; 66 offset = 1; 67 size = 1; 68 si_type = SI_TYPE_INVALID; 69 break; 70 case IPMI_DMI_TYPE_BT: 71 size = 3; 72 si_type = SI_BT; 73 break; 74 case IPMI_DMI_TYPE_KCS: 75 size = 2; 76 si_type = SI_KCS; 77 break; 78 case IPMI_DMI_TYPE_SMIC: 79 size = 2; 80 si_type = SI_SMIC; 81 break; 82 default: 83 pr_err("ipmi:dmi: Invalid IPMI type: %d\n", type); 84 return; 85 } 86 87 if (si_type != SI_TYPE_INVALID) 88 set_prop_entry(p[pidx++], "ipmi-type", u8, si_type); 89 set_prop_entry(p[pidx++], "slave-addr", u8, slave_addr); 90 set_prop_entry(p[pidx++], "addr-source", u8, SI_SMBIOS); 91 92 info = kmalloc(sizeof(*info), GFP_KERNEL); 93 if (!info) { 94 pr_warn("ipmi:dmi: Could not allocate dmi info\n"); 95 } else { 96 info->si_type = si_type; 97 info->flags = flags; 98 info->addr = base_addr; 99 info->slave_addr = slave_addr; 100 info->next = ipmi_dmi_infos; 101 ipmi_dmi_infos = info; 102 } 103 104 pdev = platform_device_alloc(name, ipmi_dmi_nr); 105 if (!pdev) { 106 pr_err("ipmi:dmi: Error allocation IPMI platform device\n"); 107 return; 108 } 109 pdev->driver_override = override; 110 111 if (type == IPMI_DMI_TYPE_SSIF) { 112 set_prop_entry(p[pidx++], "i2c-addr", u16, base_addr); 113 goto add_properties; 114 } 115 116 memset(r, 0, sizeof(r)); 117 118 r[0].start = base_addr; 119 r[0].end = r[0].start + offset - 1; 120 r[0].name = "IPMI Address 1"; 121 r[0].flags = flags; 122 123 if (size > 1) { 124 r[1].start = r[0].start + offset; 125 r[1].end = r[1].start + offset - 1; 126 r[1].name = "IPMI Address 2"; 127 r[1].flags = flags; 128 num_r++; 129 } 130 131 if (size > 2) { 132 r[2].start = r[1].start + offset; 133 r[2].end = r[2].start + offset - 1; 134 r[2].name = "IPMI Address 3"; 135 r[2].flags = flags; 136 num_r++; 137 } 138 139 if (irq) { 140 r[num_r].start = irq; 141 r[num_r].end = irq; 142 r[num_r].name = "IPMI IRQ"; 143 r[num_r].flags = IORESOURCE_IRQ; 144 num_r++; 145 } 146 147 rv = platform_device_add_resources(pdev, r, num_r); 148 if (rv) { 149 dev_err(&pdev->dev, 150 "ipmi:dmi: Unable to add resources: %d\n", rv); 151 goto err; 152 } 153 154 add_properties: 155 rv = platform_device_add_properties(pdev, p); 156 if (rv) { 157 dev_err(&pdev->dev, 158 "ipmi:dmi: Unable to add properties: %d\n", rv); 159 goto err; 160 } 161 162 rv = platform_device_add(pdev); 163 if (rv) { 164 dev_err(&pdev->dev, "ipmi:dmi: Unable to add device: %d\n", rv); 165 goto err; 166 } 167 168 ipmi_dmi_nr++; 169 return; 170 171 err: 172 platform_device_put(pdev); 173 } 174 175 /* 176 * Look up the slave address for a given interface. This is here 177 * because ACPI doesn't have a slave address while SMBIOS does, but we 178 * prefer using ACPI so the ACPI code can use the IPMI namespace. 179 * This function allows an ACPI-specified IPMI device to look up the 180 * slave address from the DMI table. 181 */ 182 int ipmi_dmi_get_slave_addr(enum si_type si_type, u32 flags, 183 unsigned long base_addr) 184 { 185 struct ipmi_dmi_info *info = ipmi_dmi_infos; 186 187 while (info) { 188 if (info->si_type == si_type && 189 info->flags == flags && 190 info->addr == base_addr) 191 return info->slave_addr; 192 info = info->next; 193 } 194 195 return 0; 196 } 197 EXPORT_SYMBOL(ipmi_dmi_get_slave_addr); 198 199 #define DMI_IPMI_MIN_LENGTH 0x10 200 #define DMI_IPMI_VER2_LENGTH 0x12 201 #define DMI_IPMI_TYPE 4 202 #define DMI_IPMI_SLAVEADDR 6 203 #define DMI_IPMI_ADDR 8 204 #define DMI_IPMI_ACCESS 0x10 205 #define DMI_IPMI_IRQ 0x11 206 #define DMI_IPMI_IO_MASK 0xfffe 207 208 static void __init dmi_decode_ipmi(const struct dmi_header *dm) 209 { 210 const u8 *data = (const u8 *) dm; 211 u32 flags = IORESOURCE_IO; 212 unsigned long base_addr; 213 u8 len = dm->length; 214 u8 slave_addr; 215 int irq = 0, offset; 216 int type; 217 218 if (len < DMI_IPMI_MIN_LENGTH) 219 return; 220 221 type = data[DMI_IPMI_TYPE]; 222 slave_addr = data[DMI_IPMI_SLAVEADDR]; 223 224 memcpy(&base_addr, data + DMI_IPMI_ADDR, sizeof(unsigned long)); 225 if (len >= DMI_IPMI_VER2_LENGTH) { 226 if (type == IPMI_DMI_TYPE_SSIF) { 227 offset = 0; 228 flags = 0; 229 base_addr = data[DMI_IPMI_ADDR] >> 1; 230 if (base_addr == 0) { 231 /* 232 * Some broken systems put the I2C address in 233 * the slave address field. We try to 234 * accommodate them here. 235 */ 236 base_addr = data[DMI_IPMI_SLAVEADDR] >> 1; 237 slave_addr = 0; 238 } 239 } else { 240 if (base_addr & 1) { 241 /* I/O */ 242 base_addr &= DMI_IPMI_IO_MASK; 243 } else { 244 /* Memory */ 245 flags = IORESOURCE_MEM; 246 } 247 248 /* 249 * If bit 4 of byte 0x10 is set, then the lsb 250 * for the address is odd. 251 */ 252 base_addr |= (data[DMI_IPMI_ACCESS] >> 4) & 1; 253 254 irq = data[DMI_IPMI_IRQ]; 255 256 /* 257 * The top two bits of byte 0x10 hold the 258 * register spacing. 259 */ 260 switch ((data[DMI_IPMI_ACCESS] >> 6) & 3) { 261 case 0: /* Byte boundaries */ 262 offset = 1; 263 break; 264 case 1: /* 32-bit boundaries */ 265 offset = 4; 266 break; 267 case 2: /* 16-byte boundaries */ 268 offset = 16; 269 break; 270 default: 271 pr_err("ipmi:dmi: Invalid offset: 0\n"); 272 return; 273 } 274 } 275 } else { 276 /* Old DMI spec. */ 277 /* 278 * Note that technically, the lower bit of the base 279 * address should be 1 if the address is I/O and 0 if 280 * the address is in memory. So many systems get that 281 * wrong (and all that I have seen are I/O) so we just 282 * ignore that bit and assume I/O. Systems that use 283 * memory should use the newer spec, anyway. 284 */ 285 base_addr = base_addr & DMI_IPMI_IO_MASK; 286 offset = 1; 287 } 288 289 dmi_add_platform_ipmi(base_addr, flags, slave_addr, irq, 290 offset, type); 291 } 292 293 static int __init scan_for_dmi_ipmi(void) 294 { 295 const struct dmi_device *dev = NULL; 296 297 while ((dev = dmi_find_device(DMI_DEV_TYPE_IPMI, NULL, dev))) 298 dmi_decode_ipmi((const struct dmi_header *) dev->device_data); 299 300 return 0; 301 } 302 subsys_initcall(scan_for_dmi_ipmi); 303