arch/arm/mach-exynos/coresight.c

   1 /* Copyright (c) 2012, Code Aurora Forum. All rights reserved.
   2  *
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License version 2 and
   5  * only version 2 as published by the Free Software Foundation.
   6  *
   7  * This program is distributed in the hope that it will be useful,
   8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10  * GNU General Public License for more details.
  11  */
  12
  13 #include <linux/kernel.h>
  14 #include <linux/module.h>
  15 #include <linux/init.h>
  16 #include <linux/types.h>
  17 #include <linux/device.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/io.h>
  20 #include <linux/err.h>
  21
  22 #include "coresight.h"
  23
  24 enum {
  25         CORESIGHT_CLK_OFF,
  26         CORESIGHT_CLK_ON_DBG,
  27         CORESIGHT_CLK_ON_HSDBG,
  28 };
  29
  30 struct coresight_ctx {
  31         struct kobject  *modulekobj;
  32         uint8_t         max_clk;
  33 };
  34
  35 static struct coresight_ctx coresight;
  36
  37
  38 struct kobject *coresight_get_modulekobj(void)
  39 {
  40         return coresight.modulekobj;
  41 }
  42
  43 #define CORESIGHT_ATTR(name)                                            \
  44 static struct kobj_attribute name##_attr =                              \
  45                 __ATTR(name, S_IRUGO | S_IWUSR, name##_show, name##_store)
  46
  47 static ssize_t max_clk_store(struct kobject *kobj,
  48                         struct kobj_attribute *attr,
  49                         const char *buf, size_t n)
  50 {
  51         unsigned long val;
  52
  53         if (sscanf(buf, "%lx", &val) != 1)
  54                 return -EINVAL;
  55
  56         coresight.max_clk = val;
  57         return n;
  58 }
  59 static ssize_t max_clk_show(struct kobject *kobj,
  60                         struct kobj_attribute *attr,
  61                         char *buf)
  62 {
  63         unsigned long val = coresight.max_clk;
  64         return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
  65 }
  66 CORESIGHT_ATTR(max_clk);
  67
  68 static int __init coresight_sysfs_init(void)
  69 {
  70         int ret;
  71
  72         coresight.modulekobj = kset_find_obj(module_kset, KBUILD_MODNAME);
  73         if (!coresight.modulekobj) {
  74                 pr_err("failed to find CORESIGHT sysfs module kobject\n");
  75                 ret = -ENOENT;
  76                 goto err;
  77         }
  78
  79         ret = sysfs_create_file(coresight.modulekobj, &max_clk_attr.attr);
  80         if (ret) {
  81                 pr_err("failed to create CORESIGHT sysfs max_clk attribute\n");
  82                 goto err;
  83         }
  84
  85         return 0;
  86 err:
  87         return ret;
  88 }
  89
  90 static void coresight_sysfs_exit(void)
  91 {
  92         sysfs_remove_file(coresight.modulekobj, &max_clk_attr.attr);
  93 }
  94
  95 static int __init coresight_init(void)
  96 {
  97         int ret;
  98
  99         ret = coresight_sysfs_init();
 100         if (ret)
 101                 goto err_sysfs;
 102         ret = etb_init();
 103         if (ret)
 104                 goto err_etb;
 105         ret = tpiu_init();
 106         if (ret)
 107                 goto err_tpiu;
 108         ret = funnel_init();
 109         if (ret)
 110                 goto err_funnel;
 111         ret = etm_init();
 112         if (ret)
 113                 goto err_etm;
 114
 115         pr_info("CORESIGHT initialized\n");
 116         return 0;
 117 err_etm:
 118         funnel_exit();
 119 err_funnel:
 120         tpiu_exit();
 121 err_tpiu:
 122         etb_exit();
 123 err_etb:
 124         coresight_sysfs_exit();
 125 err_sysfs:
 126         pr_err("CORESIGHT init failed\n");
 127         return ret;
 128 }
 129 module_init(coresight_init);
 130
 131 static void __exit coresight_exit(void)
 132 {
 133         coresight_sysfs_exit();
 134         etm_exit();
 135         funnel_exit();
 136         tpiu_exit();
 137         etb_exit();
 138 }
 139 module_exit(coresight_exit);
 140
 141 MODULE_LICENSE("GPL v2");
 142 MODULE_DESCRIPTION("CoreSight ETM Debug System Driver");