drivers/soc/ux500/ux500-soc-id.c

   1 /*
   2  * Copyright (C) ST-Ericsson SA 2010
   3  *
   4  * Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson
   5  * License terms: GNU General Public License (GPL) version 2
   6  */
   7
   8 #include <linux/kernel.h>
   9 #include <linux/init.h>
  10 #include <linux/io.h>
  11 #include <linux/module.h>
  12 #include <linux/random.h>
  13 #include <linux/slab.h>
  14 #include <linux/of.h>
  15 #include <linux/of_address.h>
  16 #include <linux/sys_soc.h>
  17
  18 #include <asm/cputype.h>
  19 #include <asm/tlbflush.h>
  20 #include <asm/cacheflush.h>
  21 #include <asm/mach/map.h>
  22
  23 /**
  24  * struct dbx500_asic_id - fields of the ASIC ID
  25  * @process: the manufacturing process, 0x40 is 40 nm 0x00 is "standard"
  26  * @partnumber: hithereto 0x8500 for DB8500
  27  * @revision: version code in the series
  28  */
  29 struct dbx500_asic_id {
  30         u16     partnumber;
  31         u8      revision;
  32         u8      process;
  33 };
  34
  35 static struct dbx500_asic_id dbx500_id;
  36
  37 static unsigned int __init ux500_read_asicid(phys_addr_t addr)
  38 {
  39         void __iomem *virt = ioremap(addr, 4);
  40         unsigned int asicid;
  41
  42         if (!virt)
  43                 return 0;
  44
  45         asicid = readl(virt);
  46         iounmap(virt);
  47
  48         return asicid;
  49 }
  50
  51 static void ux500_print_soc_info(unsigned int asicid)
  52 {
  53         unsigned int rev = dbx500_id.revision;
  54
  55         pr_info("DB%4x ", dbx500_id.partnumber);
  56
  57         if (rev == 0x01)
  58                 pr_cont("Early Drop");
  59         else if (rev >= 0xA0)
  60                 pr_cont("v%d.%d" , (rev >> 4) - 0xA + 1, rev & 0xf);
  61         else
  62                 pr_cont("Unknown");
  63
  64         pr_cont(" [%#010x]\n", asicid);
  65 }
  66
  67 static unsigned int partnumber(unsigned int asicid)
  68 {
  69         return (asicid >> 8) & 0xffff;
  70 }
  71
  72 /*
  73  * SOC          MIDR            ASICID ADDRESS          ASICID VALUE
  74  * DB8500ed     0x410fc090      0x9001FFF4              0x00850001
  75  * DB8500v1     0x411fc091      0x9001FFF4              0x008500A0
  76  * DB8500v1.1   0x411fc091      0x9001FFF4              0x008500A1
  77  * DB8500v2     0x412fc091      0x9001DBF4              0x008500B0
  78  * DB8520v2.2   0x412fc091      0x9001DBF4              0x008500B2
  79  * DB5500v1     0x412fc091      0x9001FFF4              0x005500A0
  80  * DB9540       0x413fc090      0xFFFFDBF4              0x009540xx
  81  */
  82
  83 static void __init ux500_setup_id(void)
  84 {
  85         unsigned int cpuid = read_cpuid_id();
  86         unsigned int asicid = 0;
  87         phys_addr_t addr = 0;
  88
  89         switch (cpuid) {
  90         case 0x410fc090: /* DB8500ed */
  91         case 0x411fc091: /* DB8500v1 */
  92                 addr = 0x9001FFF4;
  93                 break;
  94
  95         case 0x412fc091: /* DB8520 / DB8500v2 / DB5500v1 */
  96                 asicid = ux500_read_asicid(0x9001DBF4);
  97                 if (partnumber(asicid) == 0x8500 ||
  98                     partnumber(asicid) == 0x8520)
  99                         /* DB8500v2 */
 100                         break;
 101
 102                 /* DB5500v1 */
 103                 addr = 0x9001FFF4;
 104                 break;
 105
 106         case 0x413fc090: /* DB9540 */
 107                 addr = 0xFFFFDBF4;
 108                 break;
 109         }
 110
 111         if (addr)
 112                 asicid = ux500_read_asicid(addr);
 113
 114         if (!asicid) {
 115                 pr_err("Unable to identify SoC\n");
 116                 BUG();
 117         }
 118
 119         dbx500_id.process = asicid >> 24;
 120         dbx500_id.partnumber = partnumber(asicid);
 121         dbx500_id.revision = asicid & 0xff;
 122
 123         ux500_print_soc_info(asicid);
 124 }
 125
 126 static const char * __init ux500_get_machine(void)
 127 {
 128         return kasprintf(GFP_KERNEL, "DB%4x", dbx500_id.partnumber);
 129 }
 130
 131 static const char * __init ux500_get_family(void)
 132 {
 133         return kasprintf(GFP_KERNEL, "ux500");
 134 }
 135
 136 static const char * __init ux500_get_revision(void)
 137 {
 138         unsigned int rev = dbx500_id.revision;
 139
 140         if (rev == 0x01)
 141                 return kasprintf(GFP_KERNEL, "%s", "ED");
 142         else if (rev >= 0xA0)
 143                 return kasprintf(GFP_KERNEL, "%d.%d",
 144                                  (rev >> 4) - 0xA + 1, rev & 0xf);
 145
 146         return kasprintf(GFP_KERNEL, "%s", "Unknown");
 147 }
 148
 149 static ssize_t ux500_get_process(struct device *dev,
 150                                         struct device_attribute *attr,
 151                                         char *buf)
 152 {
 153         if (dbx500_id.process == 0x00)
 154                 return sprintf(buf, "Standard\n");
 155
 156         return sprintf(buf, "%02xnm\n", dbx500_id.process);
 157 }
 158
 159 static const char *db8500_read_soc_id(struct device_node *backupram)
 160 {
 161         void __iomem *base;
 162         void __iomem *uid;
 163         const char *retstr;
 164
 165         base = of_iomap(backupram, 0);
 166         if (!base)
 167                 return NULL;
 168         uid = base + 0x1fc0;
 169
 170         /* Throw these device-specific numbers into the entropy pool */
 171         add_device_randomness(uid, 0x14);
 172         retstr = kasprintf(GFP_KERNEL, "%08x%08x%08x%08x%08x",
 173                          readl((u32 *)uid+0),
 174                          readl((u32 *)uid+1), readl((u32 *)uid+2),
 175                          readl((u32 *)uid+3), readl((u32 *)uid+4));
 176         iounmap(base);
 177         return retstr;
 178 }
 179
 180 static void __init soc_info_populate(struct soc_device_attribute *soc_dev_attr,
 181                                      struct device_node *backupram)
 182 {
 183         soc_dev_attr->soc_id   = db8500_read_soc_id(backupram);
 184         soc_dev_attr->machine  = ux500_get_machine();
 185         soc_dev_attr->family   = ux500_get_family();
 186         soc_dev_attr->revision = ux500_get_revision();
 187 }
 188
 189 static const struct device_attribute ux500_soc_attr =
 190         __ATTR(process,  S_IRUGO, ux500_get_process,  NULL);
 191
 192 static int __init ux500_soc_device_init(void)
 193 {
 194         struct device *parent;
 195         struct soc_device *soc_dev;
 196         struct soc_device_attribute *soc_dev_attr;
 197         struct device_node *backupram;
 198
 199         backupram = of_find_compatible_node(NULL, NULL, "ste,dbx500-backupram");
 200         if (!backupram)
 201                 return 0;
 202
 203         ux500_setup_id();
 204
 205         soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
 206         if (!soc_dev_attr)
 207                 return -ENOMEM;
 208
 209         soc_info_populate(soc_dev_attr, backupram);
 210
 211         soc_dev = soc_device_register(soc_dev_attr);
 212         if (IS_ERR(soc_dev)) {
 213                 kfree(soc_dev_attr);
 214                 return PTR_ERR(soc_dev);
 215         }
 216
 217         parent = soc_device_to_device(soc_dev);
 218         device_create_file(parent, &ux500_soc_attr);
 219
 220         return 0;
 221 }
 222 subsys_initcall(ux500_soc_device_init);