android_kernel_samsung_hero.../drivers/soc/qcom/scm-errata.c
2016-08-17 16:41:52 +08:00

152 lines
3.5 KiB
C

/* Copyright (c) 2015, The Linux Foundation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
* only version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/smp.h>
#include <linux/debugfs.h>
#include <linux/cpu.h>
#include <soc/qcom/scm.h>
#define SCM_KRYO_ERRATA_ID 0x12
#define ERRATA_WA_DISABLE 0
#define ERRATA_WA_ENABLE 1
#define ERRATA_74_75_ID_BIT 0x000
#define ERRATA_76_ID_BIT 0x100
static struct dentry *debugfs_base;
static bool kryo_e74_e75_wa = true;
static bool kryo_e76_wa;
static void kryo_e74_e75_scm(void *enable)
{
int ret;
struct scm_desc desc = {0};
if (!is_scm_armv8())
return;
desc.arginfo = SCM_ARGS(1);
desc.args[0] = enable ? ERRATA_WA_ENABLE : ERRATA_WA_DISABLE;
desc.args[0] |= ERRATA_74_75_ID_BIT;
ret = scm_call2_atomic(SCM_SIP_FNID(SCM_SVC_BOOT, SCM_KRYO_ERRATA_ID),
&desc);
if (ret)
pr_err("Failed to %s ERRATA_74_75 workaround\n",
enable ? "enable" : "disable");
}
static int kryo_e74_e75_set(void *data, u64 val)
{
if ((val && kryo_e74_e75_wa) || (!val && !kryo_e74_e75_wa))
return 0;
kryo_e74_e75_wa = !!val;
get_cpu();
on_each_cpu(kryo_e74_e75_scm, (void *)kryo_e74_e75_wa, 1);
put_cpu();
return 0;
}
static int kryo_e74_e75_get(void *data, u64 *val)
{
*val = kryo_e74_e75_wa;
return 0;
}
static void kryo_e76_scm(void *enable)
{
int ret;
struct scm_desc desc = {0};
if (!is_scm_armv8())
return;
desc.arginfo = SCM_ARGS(1);
desc.args[0] = enable ? ERRATA_WA_ENABLE : ERRATA_WA_DISABLE;
desc.args[0] |= ERRATA_76_ID_BIT;
ret = scm_call2_atomic(SCM_SIP_FNID(SCM_SVC_BOOT, SCM_KRYO_ERRATA_ID),
&desc);
if (ret)
pr_err("Failed to %s ERRATA_76 workaround\n",
enable ? "enable" : "disable");
}
static int kryo_e76_set(void *data, u64 val)
{
if ((val && kryo_e76_wa) || (!val && !kryo_e76_wa))
return 0;
kryo_e76_wa = !!val;
get_cpu();
on_each_cpu(kryo_e76_scm, (void *)kryo_e76_wa, 1);
put_cpu();
return 0;
}
static int kryo_e76_get(void *data, u64 *val)
{
*val = kryo_e76_wa;
return 0;
}
DEFINE_SIMPLE_ATTRIBUTE(kryo_e74_e75_fops, kryo_e74_e75_get,
kryo_e74_e75_set, "%llu\n");
DEFINE_SIMPLE_ATTRIBUTE(kryo_e76_fops, kryo_e76_get,
kryo_e76_set, "%llu\n");
static int scm_errata_notifier_callback(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
switch (action & ~CPU_TASKS_FROZEN) {
case CPU_STARTING:
kryo_e74_e75_scm((void *)kryo_e74_e75_wa);
kryo_e76_scm((void *)kryo_e76_wa);
break;
}
return 0;
}
static struct notifier_block scm_errata_notifier = {
.notifier_call = scm_errata_notifier_callback,
};
static int __init scm_errata_init(void)
{
int ret;
debugfs_base = debugfs_create_dir("scm_errata", NULL);
if (!debugfs_base)
return -ENOMEM;
if (!debugfs_create_file("kryo_e74_e75", S_IRUGO | S_IWUSR,
debugfs_base, NULL, &kryo_e74_e75_fops))
goto err;
if (!debugfs_create_file("kryo_e76", S_IRUGO | S_IWUSR,
debugfs_base, NULL, &kryo_e76_fops))
goto err;
ret = register_hotcpu_notifier(&scm_errata_notifier);
if (ret)
goto err;
return 0;
err:
debugfs_remove_recursive(debugfs_base);
return ret;
}
device_initcall(scm_errata_init);