diff options
author | Ming Lei <ming.lei@canonical.com> | 2012-08-20 19:04:16 +0800 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-09-06 14:46:16 -0700 |
commit | ac39b3ea73aacde876d1d5ee1ca3e2719f771482 (patch) | |
tree | 58b9ee67654ea41ddba770f827d7f949ee1d40f2 | |
parent | ef40bb1bd01738670bd567e3dce8e862f2b91bf3 (diff) | |
download | op-kernel-dev-ac39b3ea73aacde876d1d5ee1ca3e2719f771482.zip op-kernel-dev-ac39b3ea73aacde876d1d5ee1ca3e2719f771482.tar.gz |
firmware loader: let caching firmware piggyback on loading firmware
After starting caching firmware, there is still some time left
before devices are suspended, during the period, request_firmware
or its nowait version may still be triggered by the below situations
to load firmware images which can't be cached during suspend/resume
cycle.
- new devices added
- driver bind
- or device open kind of things
This patch utilizes the piggyback trick to cache firmware for
this kind of situation: just increase the firmware buf's reference
count and add the fw name entry into cache entry list after starting
caching firmware and before syscore_suspend() is called.
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/base/firmware_class.c | 83 |
1 files changed, 74 insertions, 9 deletions
diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c index edc88bc..95f6851 100644 --- a/drivers/base/firmware_class.c +++ b/drivers/base/firmware_class.c @@ -25,6 +25,7 @@ #include <linux/async.h> #include <linux/pm.h> #include <linux/suspend.h> +#include <linux/syscore_ops.h> #include "base.h" @@ -105,6 +106,8 @@ struct firmware_cache { spinlock_t name_lock; struct list_head fw_names; + int state; + wait_queue_head_t wait_queue; int cnt; struct delayed_work work; @@ -146,6 +149,11 @@ struct fw_name_devm { #define to_fwbuf(d) container_of(d, struct firmware_buf, ref) +#define FW_LOADER_NO_CACHE 0 +#define FW_LOADER_START_CACHE 1 + +static int fw_cache_piggyback_on_request(const char *name); + /* fw_lock could be moved to 'struct firmware_priv' but since it is just * guarding for corner cases a global lock should be OK */ static DEFINE_MUTEX(fw_lock); @@ -741,6 +749,7 @@ static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent, int retval = 0; struct device *f_dev = &fw_priv->dev; struct firmware_buf *buf = fw_priv->buf; + struct firmware_cache *fwc = &fw_cache; dev_set_uevent_suppress(f_dev, true); @@ -796,6 +805,15 @@ static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent, if (!retval) retval = fw_map_pages_buf(buf); + /* + * After caching firmware image is started, let it piggyback + * on request firmware. + */ + if (!retval && fwc->state == FW_LOADER_START_CACHE) { + if (fw_cache_piggyback_on_request(buf->fw_id)) + kref_get(&buf->ref); + } + /* pass the pages buffer to driver at the last minute */ fw_set_page_data(buf, fw_priv->fw); @@ -1041,6 +1059,29 @@ exit: return fce; } +static int fw_cache_piggyback_on_request(const char *name) +{ + struct firmware_cache *fwc = &fw_cache; + struct fw_cache_entry *fce; + int ret = 0; + + spin_lock(&fwc->name_lock); + list_for_each_entry(fce, &fwc->fw_names, list) { + if (!strcmp(fce->name, name)) + goto found; + } + + fce = alloc_fw_cache_entry(name); + if (fce) { + ret = 1; + list_add(&fce->list, &fwc->fw_names); + pr_debug("%s: fw: %s\n", __func__, name); + } +found: + spin_unlock(&fwc->name_lock); + return ret; +} + static void free_fw_cache_entry(struct fw_cache_entry *fce) { kfree(fce); @@ -1054,17 +1095,14 @@ static void __async_dev_cache_fw_image(void *fw_entry, int ret; ret = cache_firmware(fce->name); - if (ret) - goto free; + if (ret) { + spin_lock(&fwc->name_lock); + list_del(&fce->list); + spin_unlock(&fwc->name_lock); - spin_lock(&fwc->name_lock); - list_add(&fce->list, &fwc->fw_names); - spin_unlock(&fwc->name_lock); - goto drop_ref; + free_fw_cache_entry(fce); + } -free: - free_fw_cache_entry(fce); -drop_ref: spin_lock(&fwc->name_lock); fwc->cnt--; spin_unlock(&fwc->name_lock); @@ -1109,6 +1147,7 @@ static void dev_cache_fw_image(struct device *dev, void *data) spin_lock(&fwc->name_lock); fwc->cnt++; + list_add(&fce->list, &fwc->fw_names); spin_unlock(&fwc->name_lock); async_schedule(__async_dev_cache_fw_image, (void *)fce); @@ -1164,7 +1203,10 @@ static void device_cache_fw_images(void) old_timeout = loading_timeout; loading_timeout = 10; + mutex_lock(&fw_lock); + fwc->state = FW_LOADER_START_CACHE; dpm_for_each_dev(NULL, dev_cache_fw_image); + mutex_unlock(&fw_lock); /* wait for completion of caching firmware for all devices */ spin_lock(&fwc->name_lock); @@ -1229,6 +1271,14 @@ static int fw_pm_notify(struct notifier_block *notify_block, case PM_POST_SUSPEND: case PM_POST_HIBERNATION: case PM_POST_RESTORE: + /* + * In case that system sleep failed and syscore_suspend is + * not called. + */ + mutex_lock(&fw_lock); + fw_cache.state = FW_LOADER_NO_CACHE; + mutex_unlock(&fw_lock); + device_uncache_fw_images_delay(10 * MSEC_PER_SEC); break; } @@ -1243,6 +1293,17 @@ static int fw_pm_notify(struct notifier_block *notify_block, } #endif +/* stop caching firmware once syscore_suspend is reached */ +static int fw_suspend(void) +{ + fw_cache.state = FW_LOADER_NO_CACHE; + return 0; +} + +static struct syscore_ops fw_syscore_ops = { + .suspend = fw_suspend, +}; + static void __init fw_cache_init(void) { spin_lock_init(&fw_cache.lock); @@ -1251,6 +1312,7 @@ static void __init fw_cache_init(void) spin_lock_init(&fw_cache.name_lock); INIT_LIST_HEAD(&fw_cache.fw_names); fw_cache.cnt = 0; + fw_cache.state = FW_LOADER_NO_CACHE; init_waitqueue_head(&fw_cache.wait_queue); INIT_DELAYED_WORK(&fw_cache.work, @@ -1258,6 +1320,8 @@ static void __init fw_cache_init(void) fw_cache.pm_notify.notifier_call = fw_pm_notify; register_pm_notifier(&fw_cache.pm_notify); + + register_syscore_ops(&fw_syscore_ops); } static int __init firmware_class_init(void) @@ -1268,6 +1332,7 @@ static int __init firmware_class_init(void) static void __exit firmware_class_exit(void) { + unregister_syscore_ops(&fw_syscore_ops); unregister_pm_notifier(&fw_cache.pm_notify); class_unregister(&firmware_class); } |