From: Inaky Perez-Gonzalez Date: Mon, 14 Sep 2009 21:10:16 +0000 (-0700) Subject: wimax/i2400m: cache firmware on system suspend X-Git-Tag: v2.6.33-rc1~388^2~487^2~33 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=7b43ca708a767a5f68eeeb732c569c0f11a7d6f7;p=platform%2Fkernel%2Flinux-3.10.git wimax/i2400m: cache firmware on system suspend In preparation for a reset_resume implementation, have the firmware image be cached in memory when the system goes to suspend and released when out. This is needed in case the device resets during suspend; the driver can't load firmware until resume is completed or bad deadlocks happen. The modus operandi for this was copied from the Orinoco USB driver. The caching is done with a kobject to avoid race conditions when releasing it. The fw loader path is altered only to first check for a cached image before trying to load from disk. A Power Management event notifier is register to call i2400m_fw_cache() or i2400m_fw_uncache() which take care of the actual cache management. Signed-off-by: Inaky Perez-Gonzalez --- diff --git a/drivers/net/wimax/i2400m/driver.c b/drivers/net/wimax/i2400m/driver.c index f07d852..07d12be 100644 --- a/drivers/net/wimax/i2400m/driver.c +++ b/drivers/net/wimax/i2400m/driver.c @@ -66,6 +66,7 @@ #include #include #include +#include #define D_SUBMODULE driver #include "debug-levels.h" @@ -555,6 +556,51 @@ void i2400m_dev_stop(struct i2400m *i2400m) /* + * Listen to PM events to cache the firmware before suspend/hibernation + * + * When the device comes out of suspend, it might go into reset and + * firmware has to be uploaded again. At resume, most of the times, we + * can't load firmware images from disk, so we need to cache it. + * + * i2400m_fw_cache() will allocate a kobject and attach the firmware + * to it; that way we don't have to worry too much about the fw loader + * hitting a race condition. + * + * Note: modus operandi stolen from the Orinoco driver; thx. + */ +static +int i2400m_pm_notifier(struct notifier_block *notifier, + unsigned long pm_event, + void *unused) +{ + struct i2400m *i2400m = + container_of(notifier, struct i2400m, pm_notifier); + struct device *dev = i2400m_dev(i2400m); + + d_fnstart(3, dev, "(i2400m %p pm_event %lx)\n", i2400m, pm_event); + switch (pm_event) { + case PM_HIBERNATION_PREPARE: + case PM_SUSPEND_PREPARE: + i2400m_fw_cache(i2400m); + break; + case PM_POST_RESTORE: + /* Restore from hibernation failed. We need to clean + * up in exactly the same way, so fall through. */ + case PM_POST_HIBERNATION: + case PM_POST_SUSPEND: + i2400m_fw_uncache(i2400m); + break; + + case PM_RESTORE_PREPARE: + default: + break; + } + d_fnend(3, dev, "(i2400m %p pm_event %lx) = void\n", i2400m, pm_event); + return NOTIFY_DONE; +} + + +/* * The device has rebooted; fix up the device and the driver * * Tear down the driver communication with the device, reload the @@ -738,6 +784,9 @@ int i2400m_setup(struct i2400m *i2400m, enum i2400m_bri bm_flags) goto error_read_mac_addr; random_ether_addr(i2400m->src_mac_addr); + i2400m->pm_notifier.notifier_call = i2400m_pm_notifier; + register_pm_notifier(&i2400m->pm_notifier); + result = register_netdev(net_dev); /* Okey dokey, bring it up */ if (result < 0) { dev_err(dev, "cannot register i2400m network device: %d\n", @@ -783,6 +832,7 @@ error_wimax_dev_add: error_dev_start: unregister_netdev(net_dev); error_register_netdev: + unregister_pm_notifier(&i2400m->pm_notifier); error_read_mac_addr: error_bootrom_init: d_fnend(3, dev, "(i2400m %p) = %d\n", i2400m, result); @@ -809,6 +859,7 @@ void i2400m_release(struct i2400m *i2400m) wimax_dev_rm(&i2400m->wimax_dev); i2400m_dev_stop(i2400m); unregister_netdev(i2400m->wimax_dev.net_dev); + unregister_pm_notifier(&i2400m->pm_notifier); kfree(i2400m->bm_ack_buf); kfree(i2400m->bm_cmd_buf); d_fnend(3, dev, "(i2400m %p) = void\n", i2400m); diff --git a/drivers/net/wimax/i2400m/fw.c b/drivers/net/wimax/i2400m/fw.c index 5719f4a..69f9e45 100644 --- a/drivers/net/wimax/i2400m/fw.c +++ b/drivers/net/wimax/i2400m/fw.c @@ -105,6 +105,13 @@ * read an acknolwedgement from it (or an asynchronous notification) * from it. * + * FIRMWARE LOADING + * + * Note that in some cases, we can't just load a firmware file (for + * example, when resuming). For that, we might cache the firmware + * file. Thus, when doing the bootstrap, if there is a cache firmware + * file, it is used; if not, loading from disk is attempted. + * * ROADMAP * * i2400m_barker_db_init Called by i2400m_driver_init() @@ -114,9 +121,10 @@ * * i2400m_dev_bootstrap Called by __i2400m_dev_start() * request_firmware - * i2400m_fw_check - * i2400m_fw_hdr_check - * i2400m_fw_dnload + * i2400m_fw_bootstrap + * i2400m_fw_check + * i2400m_fw_hdr_check + * i2400m_fw_dnload * release_firmware * * i2400m_fw_dnload @@ -141,6 +149,10 @@ * * i2400m_bm_cmd_prepare Used by bus-drivers to prep * commands before sending + * + * i2400m_pm_notifier Called on Power Management events + * i2400m_fw_cache + * i2400m_fw_uncache */ #include #include @@ -1459,6 +1471,61 @@ error_dev_rebooted: goto hw_reboot; } +static +int i2400m_fw_bootstrap(struct i2400m *i2400m, const struct firmware *fw, + enum i2400m_bri flags) +{ + int ret; + struct device *dev = i2400m_dev(i2400m); + const struct i2400m_bcf_hdr *bcf; /* Firmware data */ + + d_fnstart(5, dev, "(i2400m %p)\n", i2400m); + bcf = (void *) fw->data; + ret = i2400m_fw_check(i2400m, bcf, fw->size); + if (ret >= 0) + ret = i2400m_fw_dnload(i2400m, bcf, fw->size, flags); + if (ret < 0) + dev_err(dev, "%s: cannot use: %d, skipping\n", + i2400m->fw_name, ret); + kfree(i2400m->fw_hdrs); + i2400m->fw_hdrs = NULL; + d_fnend(5, dev, "(i2400m %p) = %d\n", i2400m, ret); + return ret; +} + + +/* Refcounted container for firmware data */ +struct i2400m_fw { + struct kref kref; + const struct firmware *fw; +}; + + +static +void i2400m_fw_destroy(struct kref *kref) +{ + struct i2400m_fw *i2400m_fw = + container_of(kref, struct i2400m_fw, kref); + release_firmware(i2400m_fw->fw); + kfree(i2400m_fw); +} + + +static +struct i2400m_fw *i2400m_fw_get(struct i2400m_fw *i2400m_fw) +{ + if (i2400m_fw != NULL && i2400m_fw != (void *) ~0) + kref_get(&i2400m_fw->kref); + return i2400m_fw; +} + + +static +void i2400m_fw_put(struct i2400m_fw *i2400m_fw) +{ + kref_put(&i2400m_fw->kref, i2400m_fw_destroy); +} + /** * i2400m_dev_bootstrap - Bring the device to a known state and upload firmware @@ -1479,12 +1546,28 @@ int i2400m_dev_bootstrap(struct i2400m *i2400m, enum i2400m_bri flags) { int ret, itr; struct device *dev = i2400m_dev(i2400m); - const struct firmware *fw; + struct i2400m_fw *i2400m_fw; const struct i2400m_bcf_hdr *bcf; /* Firmware data */ + const struct firmware *fw; const char *fw_name; d_fnstart(5, dev, "(i2400m %p)\n", i2400m); + ret = -ENODEV; + spin_lock(&i2400m->rx_lock); + i2400m_fw = i2400m_fw_get(i2400m->fw_cached); + spin_unlock(&i2400m->rx_lock); + if (i2400m_fw == (void *) ~0) { + dev_err(dev, "can't load firmware now!"); + goto out; + } else if (i2400m_fw != NULL) { + dev_info(dev, "firmware %s: loading from cache\n", + i2400m->fw_name); + ret = i2400m_fw_bootstrap(i2400m, i2400m_fw->fw, flags); + i2400m_fw_put(i2400m_fw); + goto out; + } + /* Load firmware files to memory. */ for (itr = 0, bcf = NULL, ret = -ENOENT; ; itr++) { fw_name = i2400m->bus_fw_names[itr]; @@ -1500,21 +1583,71 @@ int i2400m_dev_bootstrap(struct i2400m *i2400m, enum i2400m_bri flags) fw_name, ret); continue; } - bcf = (void *) fw->data; i2400m->fw_name = fw_name; - ret = i2400m_fw_check(i2400m, bcf, fw->size); - if (ret >= 0) - ret = i2400m_fw_dnload(i2400m, bcf, fw->size, flags); - if (ret < 0) - dev_err(dev, "%s: cannot use: %d, skipping\n", - fw_name, ret); - kfree(i2400m->fw_hdrs); - i2400m->fw_hdrs = NULL; + ret = i2400m_fw_bootstrap(i2400m, fw, flags); release_firmware(fw); if (ret >= 0) /* firmware loaded succesfully */ break; + i2400m->fw_name = NULL; } +out: d_fnend(5, dev, "(i2400m %p) = %d\n", i2400m, ret); return ret; } EXPORT_SYMBOL_GPL(i2400m_dev_bootstrap); + + +void i2400m_fw_cache(struct i2400m *i2400m) +{ + int result; + struct i2400m_fw *i2400m_fw; + struct device *dev = i2400m_dev(i2400m); + + /* if there is anything there, free it -- now, this'd be weird */ + spin_lock(&i2400m->rx_lock); + i2400m_fw = i2400m->fw_cached; + spin_unlock(&i2400m->rx_lock); + if (i2400m_fw != NULL && i2400m_fw != (void *) ~0) { + i2400m_fw_put(i2400m_fw); + WARN(1, "%s:%u: still cached fw still present?\n", + __func__, __LINE__); + } + + if (i2400m->fw_name == NULL) { + dev_err(dev, "firmware n/a: can't cache\n"); + i2400m_fw = (void *) ~0; + goto out; + } + + i2400m_fw = kzalloc(sizeof(*i2400m_fw), GFP_ATOMIC); + if (i2400m_fw == NULL) + goto out; + kref_init(&i2400m_fw->kref); + result = request_firmware(&i2400m_fw->fw, i2400m->fw_name, dev); + if (result < 0) { + dev_err(dev, "firmware %s: failed to cache: %d\n", + i2400m->fw_name, result); + kfree(i2400m_fw); + i2400m_fw = (void *) ~0; + } else + dev_info(dev, "firmware %s: cached\n", i2400m->fw_name); +out: + spin_lock(&i2400m->rx_lock); + i2400m->fw_cached = i2400m_fw; + spin_unlock(&i2400m->rx_lock); +} + + +void i2400m_fw_uncache(struct i2400m *i2400m) +{ + struct i2400m_fw *i2400m_fw; + + spin_lock(&i2400m->rx_lock); + i2400m_fw = i2400m->fw_cached; + i2400m->fw_cached = NULL; + spin_unlock(&i2400m->rx_lock); + + if (i2400m_fw != NULL && i2400m_fw != (void *) ~0) + i2400m_fw_put(i2400m_fw); +} + diff --git a/drivers/net/wimax/i2400m/i2400m.h b/drivers/net/wimax/i2400m/i2400m.h index 0c165de..916b1d3 100644 --- a/drivers/net/wimax/i2400m/i2400m.h +++ b/drivers/net/wimax/i2400m/i2400m.h @@ -424,11 +424,21 @@ struct i2400m_barker_db; * @fw_hdrs: NULL terminated array of pointers to the firmware * headers. This is only available during firmware load time. * + * @fw_cached: Used to cache firmware when the system goes to + * suspend/standby/hibernation (as on resume we can't read it). If + * NULL, no firmware was cached, read it. If ~0, you can't read + * any firmware files (the system still didn't come out of suspend + * and failed to cache one), so abort; otherwise, a valid cached + * firmware to be used. Access to this variable is protected by + * the spinlock i2400m->rx_lock. + * * @barker: barker type that the device uses; this is initialized by * i2400m_is_boot_barker() the first time it is called. Then it * won't change during the life cycle of the device and everytime * a boot barker is received, it is just verified for it being the * same. + * + * @pm_notifier: used to register for PM events */ struct i2400m { struct wimax_dev wimax_dev; /* FIRST! See doc */ @@ -495,7 +505,10 @@ struct i2400m { const char *fw_name; /* name of the current firmware image */ unsigned long fw_version; /* version of the firmware interface */ const struct i2400m_bcf_hdr **fw_hdrs; + struct i2400m_fw *fw_cached; /* protected by rx_lock */ struct i2400m_barker_db *barker; + + struct notifier_block pm_notifier; }; @@ -671,6 +684,9 @@ extern void i2400m_tx_release(struct i2400m *); extern int i2400m_rx_setup(struct i2400m *); extern void i2400m_rx_release(struct i2400m *); +extern void i2400m_fw_cache(struct i2400m *); +extern void i2400m_fw_uncache(struct i2400m *); + extern void i2400m_net_rx(struct i2400m *, struct sk_buff *, unsigned, const void *, int); extern void i2400m_net_erx(struct i2400m *, struct sk_buff *,