forked from torvalds/linux
-
Notifications
You must be signed in to change notification settings - Fork 0
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
powerpc/powernv: Enable reading and updating of system parameters
This patch enables reading and updating of system parameters through OPAL call. Signed-off-by: Neelesh Gupta <[email protected]> Signed-off-by: Benjamin Herrenschmidt <[email protected]>
- Loading branch information
Showing
5 changed files
with
310 additions
and
2 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,290 @@ | ||
| /* | ||
| * PowerNV system parameter code | ||
| * | ||
| * Copyright (C) 2013 IBM | ||
| * | ||
| * This program is free software; you can redistribute it and/or modify | ||
| * it under the terms of the GNU General Public License as published by | ||
| * the Free Software Foundation; either version 2 of the License, or | ||
| * (at your option) any later version. | ||
| * | ||
| * 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. | ||
| * | ||
| * You should have received a copy of the GNU General Public License | ||
| * along with this program; if not, write to the Free Software | ||
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | ||
| */ | ||
|
|
||
| #include <linux/kobject.h> | ||
| #include <linux/mutex.h> | ||
| #include <linux/slab.h> | ||
| #include <linux/of.h> | ||
| #include <linux/gfp.h> | ||
| #include <linux/stat.h> | ||
| #include <asm/opal.h> | ||
|
|
||
| #define MAX_PARAM_DATA_LEN 64 | ||
|
|
||
| static DEFINE_MUTEX(opal_sysparam_mutex); | ||
| static struct kobject *sysparam_kobj; | ||
| static void *param_data_buf; | ||
|
|
||
| struct param_attr { | ||
| struct list_head list; | ||
| u32 param_id; | ||
| u32 param_size; | ||
| struct kobj_attribute kobj_attr; | ||
| }; | ||
|
|
||
| static int opal_get_sys_param(u32 param_id, u32 length, void *buffer) | ||
| { | ||
| struct opal_msg msg; | ||
| int ret, token; | ||
|
|
||
| token = opal_async_get_token_interruptible(); | ||
| if (token < 0) { | ||
| if (token != -ERESTARTSYS) | ||
| pr_err("%s: Couldn't get the token, returning\n", | ||
| __func__); | ||
| ret = token; | ||
| goto out; | ||
| } | ||
|
|
||
| ret = opal_get_param(token, param_id, (u64)buffer, length); | ||
| if (ret != OPAL_ASYNC_COMPLETION) | ||
| goto out_token; | ||
|
|
||
| ret = opal_async_wait_response(token, &msg); | ||
| if (ret) { | ||
| pr_err("%s: Failed to wait for the async response, %d\n", | ||
| __func__, ret); | ||
| goto out_token; | ||
| } | ||
|
|
||
| ret = msg.params[1]; | ||
|
|
||
| out_token: | ||
| opal_async_release_token(token); | ||
| out: | ||
| return ret; | ||
| } | ||
|
|
||
| static int opal_set_sys_param(u32 param_id, u32 length, void *buffer) | ||
| { | ||
| struct opal_msg msg; | ||
| int ret, token; | ||
|
|
||
| token = opal_async_get_token_interruptible(); | ||
| if (token < 0) { | ||
| if (token != -ERESTARTSYS) | ||
| pr_err("%s: Couldn't get the token, returning\n", | ||
| __func__); | ||
| ret = token; | ||
| goto out; | ||
| } | ||
|
|
||
| ret = opal_set_param(token, param_id, (u64)buffer, length); | ||
|
|
||
| if (ret != OPAL_ASYNC_COMPLETION) | ||
| goto out_token; | ||
|
|
||
| ret = opal_async_wait_response(token, &msg); | ||
| if (ret) { | ||
| pr_err("%s: Failed to wait for the async response, %d\n", | ||
| __func__, ret); | ||
| goto out_token; | ||
| } | ||
|
|
||
| ret = msg.params[1]; | ||
|
|
||
| out_token: | ||
| opal_async_release_token(token); | ||
| out: | ||
| return ret; | ||
| } | ||
|
|
||
| static ssize_t sys_param_show(struct kobject *kobj, | ||
| struct kobj_attribute *kobj_attr, char *buf) | ||
| { | ||
| struct param_attr *attr = container_of(kobj_attr, struct param_attr, | ||
| kobj_attr); | ||
| int ret; | ||
|
|
||
| mutex_lock(&opal_sysparam_mutex); | ||
| ret = opal_get_sys_param(attr->param_id, attr->param_size, | ||
| param_data_buf); | ||
| if (ret) | ||
| goto out; | ||
|
|
||
| memcpy(buf, param_data_buf, attr->param_size); | ||
|
|
||
| out: | ||
| mutex_unlock(&opal_sysparam_mutex); | ||
| return ret ? ret : attr->param_size; | ||
| } | ||
|
|
||
| static ssize_t sys_param_store(struct kobject *kobj, | ||
| struct kobj_attribute *kobj_attr, const char *buf, size_t count) | ||
| { | ||
| struct param_attr *attr = container_of(kobj_attr, struct param_attr, | ||
| kobj_attr); | ||
| int ret; | ||
|
|
||
| mutex_lock(&opal_sysparam_mutex); | ||
| memcpy(param_data_buf, buf, count); | ||
| ret = opal_set_sys_param(attr->param_id, attr->param_size, | ||
| param_data_buf); | ||
| mutex_unlock(&opal_sysparam_mutex); | ||
| return ret ? ret : count; | ||
| } | ||
|
|
||
| void __init opal_sys_param_init(void) | ||
| { | ||
| struct device_node *sysparam; | ||
| struct param_attr *attr; | ||
| u32 *id, *size; | ||
| int count, i; | ||
| u8 *perm; | ||
|
|
||
| if (!opal_kobj) { | ||
| pr_warn("SYSPARAM: opal kobject is not available\n"); | ||
| goto out; | ||
| } | ||
|
|
||
| sysparam_kobj = kobject_create_and_add("sysparams", opal_kobj); | ||
| if (!sysparam_kobj) { | ||
| pr_err("SYSPARAM: Failed to create sysparam kobject\n"); | ||
| goto out; | ||
| } | ||
|
|
||
| /* Allocate big enough buffer for any get/set transactions */ | ||
| param_data_buf = kzalloc(MAX_PARAM_DATA_LEN, GFP_KERNEL); | ||
| if (!param_data_buf) { | ||
| pr_err("SYSPARAM: Failed to allocate memory for param data " | ||
| "buf\n"); | ||
| goto out_kobj_put; | ||
| } | ||
|
|
||
| sysparam = of_find_node_by_path("/ibm,opal/sysparams"); | ||
| if (!sysparam) { | ||
| pr_err("SYSPARAM: Opal sysparam node not found\n"); | ||
| goto out_param_buf; | ||
| } | ||
|
|
||
| if (!of_device_is_compatible(sysparam, "ibm,opal-sysparams")) { | ||
| pr_err("SYSPARAM: Opal sysparam node not compatible\n"); | ||
| goto out_node_put; | ||
| } | ||
|
|
||
| /* Number of parameters exposed through DT */ | ||
| count = of_property_count_strings(sysparam, "param-name"); | ||
| if (count < 0) { | ||
| pr_err("SYSPARAM: No string found of property param-name in " | ||
| "the node %s\n", sysparam->name); | ||
| goto out_node_put; | ||
| } | ||
|
|
||
| id = kzalloc(sizeof(*id) * count, GFP_KERNEL); | ||
| if (!id) { | ||
| pr_err("SYSPARAM: Failed to allocate memory to read parameter " | ||
| "id\n"); | ||
| goto out_node_put; | ||
| } | ||
|
|
||
| size = kzalloc(sizeof(*size) * count, GFP_KERNEL); | ||
| if (!size) { | ||
| pr_err("SYSPARAM: Failed to allocate memory to read parameter " | ||
| "size\n"); | ||
| goto out_free_id; | ||
| } | ||
|
|
||
| perm = kzalloc(sizeof(*perm) * count, GFP_KERNEL); | ||
| if (!perm) { | ||
| pr_err("SYSPARAM: Failed to allocate memory to read supported " | ||
| "action on the parameter"); | ||
| goto out_free_size; | ||
| } | ||
|
|
||
| if (of_property_read_u32_array(sysparam, "param-id", id, count)) { | ||
| pr_err("SYSPARAM: Missing property param-id in the DT\n"); | ||
| goto out_free_perm; | ||
| } | ||
|
|
||
| if (of_property_read_u32_array(sysparam, "param-len", size, count)) { | ||
| pr_err("SYSPARAM: Missing propery param-len in the DT\n"); | ||
| goto out_free_perm; | ||
| } | ||
|
|
||
|
|
||
| if (of_property_read_u8_array(sysparam, "param-perm", perm, count)) { | ||
| pr_err("SYSPARAM: Missing propery param-perm in the DT\n"); | ||
| goto out_free_perm; | ||
| } | ||
|
|
||
| attr = kzalloc(sizeof(*attr) * count, GFP_KERNEL); | ||
| if (!attr) { | ||
| pr_err("SYSPARAM: Failed to allocate memory for parameter " | ||
| "attributes\n"); | ||
| goto out_free_perm; | ||
| } | ||
|
|
||
| /* For each of the parameters, populate the parameter attributes */ | ||
| for (i = 0; i < count; i++) { | ||
| sysfs_attr_init(&attr[i].kobj_attr.attr); | ||
| attr[i].param_id = id[i]; | ||
| attr[i].param_size = size[i]; | ||
| if (of_property_read_string_index(sysparam, "param-name", i, | ||
| &attr[i].kobj_attr.attr.name)) | ||
| continue; | ||
|
|
||
| /* If the parameter is read-only or read-write */ | ||
| switch (perm[i] & 3) { | ||
| case OPAL_SYSPARAM_READ: | ||
| attr[i].kobj_attr.attr.mode = S_IRUGO; | ||
| break; | ||
| case OPAL_SYSPARAM_WRITE: | ||
| attr[i].kobj_attr.attr.mode = S_IWUGO; | ||
| break; | ||
| case OPAL_SYSPARAM_RW: | ||
| attr[i].kobj_attr.attr.mode = S_IRUGO | S_IWUGO; | ||
| break; | ||
| default: | ||
| break; | ||
| } | ||
|
|
||
| attr[i].kobj_attr.show = sys_param_show; | ||
| attr[i].kobj_attr.store = sys_param_store; | ||
|
|
||
| if (sysfs_create_file(sysparam_kobj, &attr[i].kobj_attr.attr)) { | ||
| pr_err("SYSPARAM: Failed to create sysfs file %s\n", | ||
| attr[i].kobj_attr.attr.name); | ||
| goto out_free_attr; | ||
| } | ||
| } | ||
|
|
||
| kfree(perm); | ||
| kfree(size); | ||
| kfree(id); | ||
| of_node_put(sysparam); | ||
| return; | ||
|
|
||
| out_free_attr: | ||
| kfree(attr); | ||
| out_free_perm: | ||
| kfree(perm); | ||
| out_free_size: | ||
| kfree(size); | ||
| out_free_id: | ||
| kfree(id); | ||
| out_node_put: | ||
| of_node_put(sysparam); | ||
| out_param_buf: | ||
| kfree(param_data_buf); | ||
| out_kobj_put: | ||
| kobject_put(sysparam_kobj); | ||
| out: | ||
| return; | ||
| } |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters