diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-06-11 22:09:19 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-06-11 22:09:19 +0300 |
commit | 6f75edeadd0dd3d58017bc3bcdc2b80879a7cfd3 (patch) | |
tree | e75729deec3343feec7a19820fba633df4aea9b0 /drivers/hwspinlock | |
parent | d2b2250c3e565038a746b5db1de2af20a6468f02 (diff) | |
parent | e759176c7f6b6d84a31276e11d687f232f6e4ecf (diff) | |
download | linux-6f75edeadd0dd3d58017bc3bcdc2b80879a7cfd3.tar.xz |
Merge tag 'hwlock-v4.18' of git://github.com/andersson/remoteproc
Pull hwspinlock updates from Bjorn Andersson:
"In addition to migrating the files to use SPDX license headers this
introduces the ability for clients to operate a hwlock without the
framework taking any additional locks"
* tag 'hwlock-v4.18' of git://github.com/andersson/remoteproc:
hwspinlock/u8500: Switch to SPDX license identifier
hwspinlock: sprd: Switch to SPDX license identifier
hwspinlock/sirf: Switch to SPDX license identifier
hwspinlock: qcom: Switch to SPDX license identifier
hwspinlock/omap: Switch to SPDX license identifier
hwspinlock/core: Switch to SPDX license identifier
hwspinlock: Introduce one new mode for hwspinlock
hwspinlock: Convert to use 'switch' statement
Diffstat (limited to 'drivers/hwspinlock')
-rw-r--r-- | drivers/hwspinlock/Kconfig | 1 | ||||
-rw-r--r-- | drivers/hwspinlock/hwspinlock_core.c | 77 | ||||
-rw-r--r-- | drivers/hwspinlock/hwspinlock_internal.h | 10 | ||||
-rw-r--r-- | drivers/hwspinlock/omap_hwspinlock.c | 10 | ||||
-rw-r--r-- | drivers/hwspinlock/qcom_hwspinlock.c | 10 | ||||
-rw-r--r-- | drivers/hwspinlock/sirf_hwspinlock.c | 3 | ||||
-rw-r--r-- | drivers/hwspinlock/sprd_hwspinlock.c | 10 | ||||
-rw-r--r-- | drivers/hwspinlock/u8500_hsem.c | 10 |
8 files changed, 59 insertions, 72 deletions
diff --git a/drivers/hwspinlock/Kconfig b/drivers/hwspinlock/Kconfig index f0f467983960..e895d29500ee 100644 --- a/drivers/hwspinlock/Kconfig +++ b/drivers/hwspinlock/Kconfig @@ -1,3 +1,4 @@ +# SPDX-License-Identifier: GPL-2.0 # # Generic HWSPINLOCK framework # diff --git a/drivers/hwspinlock/hwspinlock_core.c b/drivers/hwspinlock/hwspinlock_core.c index 4074441444fe..d16e6a3d38e8 100644 --- a/drivers/hwspinlock/hwspinlock_core.c +++ b/drivers/hwspinlock/hwspinlock_core.c @@ -1,18 +1,10 @@ +// SPDX-License-Identifier: GPL-2.0 /* * Hardware spinlock framework * * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com * * Contact: Ohad Ben-Cohen <ohad@wizery.com> - * - * This program is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License 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. */ #define pr_fmt(fmt) "%s: " fmt, __func__ @@ -71,10 +63,16 @@ static DEFINE_MUTEX(hwspinlock_tree_lock); * This function attempts to lock an hwspinlock, and will immediately * fail if the hwspinlock is already taken. * - * Upon a successful return from this function, preemption (and possibly - * interrupts) is disabled, so the caller must not sleep, and is advised to - * release the hwspinlock as soon as possible. This is required in order to - * minimize remote cores polling on the hardware interconnect. + * Caution: If the mode is HWLOCK_RAW, that means user must protect the routine + * of getting hardware lock with mutex or spinlock. Since in some scenarios, + * user need some time-consuming or sleepable operations under the hardware + * lock, they need one sleepable lock (like mutex) to protect the operations. + * + * If the mode is not HWLOCK_RAW, upon a successful return from this function, + * preemption (and possibly interrupts) is disabled, so the caller must not + * sleep, and is advised to release the hwspinlock as soon as possible. This is + * required in order to minimize remote cores polling on the hardware + * interconnect. * * The user decides whether local interrupts are disabled or not, and if yes, * whether he wants their previous state to be saved. It is up to the user @@ -106,12 +104,20 @@ int __hwspin_trylock(struct hwspinlock *hwlock, int mode, unsigned long *flags) * problems with hwspinlock usage (e.g. scheduler checks like * 'scheduling while atomic' etc.) */ - if (mode == HWLOCK_IRQSTATE) + switch (mode) { + case HWLOCK_IRQSTATE: ret = spin_trylock_irqsave(&hwlock->lock, *flags); - else if (mode == HWLOCK_IRQ) + break; + case HWLOCK_IRQ: ret = spin_trylock_irq(&hwlock->lock); - else + break; + case HWLOCK_RAW: + ret = 1; + break; + default: ret = spin_trylock(&hwlock->lock); + break; + } /* is lock already taken by another context on the local cpu ? */ if (!ret) @@ -122,12 +128,20 @@ int __hwspin_trylock(struct hwspinlock *hwlock, int mode, unsigned long *flags) /* if hwlock is already taken, undo spin_trylock_* and exit */ if (!ret) { - if (mode == HWLOCK_IRQSTATE) + switch (mode) { + case HWLOCK_IRQSTATE: spin_unlock_irqrestore(&hwlock->lock, *flags); - else if (mode == HWLOCK_IRQ) + break; + case HWLOCK_IRQ: spin_unlock_irq(&hwlock->lock); - else + break; + case HWLOCK_RAW: + /* Nothing to do */ + break; + default: spin_unlock(&hwlock->lock); + break; + } return -EBUSY; } @@ -160,9 +174,14 @@ EXPORT_SYMBOL_GPL(__hwspin_trylock); * is already taken, the function will busy loop waiting for it to * be released, but give up after @timeout msecs have elapsed. * - * Upon a successful return from this function, preemption is disabled - * (and possibly local interrupts, too), so the caller must not sleep, - * and is advised to release the hwspinlock as soon as possible. + * Caution: If the mode is HWLOCK_RAW, that means user must protect the routine + * of getting hardware lock with mutex or spinlock. Since in some scenarios, + * user need some time-consuming or sleepable operations under the hardware + * lock, they need one sleepable lock (like mutex) to protect the operations. + * + * If the mode is not HWLOCK_RAW, upon a successful return from this function, + * preemption is disabled (and possibly local interrupts, too), so the caller + * must not sleep, and is advised to release the hwspinlock as soon as possible. * This is required in order to minimize remote cores polling on the * hardware interconnect. * @@ -249,12 +268,20 @@ void __hwspin_unlock(struct hwspinlock *hwlock, int mode, unsigned long *flags) hwlock->bank->ops->unlock(hwlock); /* Undo the spin_trylock{_irq, _irqsave} called while locking */ - if (mode == HWLOCK_IRQSTATE) + switch (mode) { + case HWLOCK_IRQSTATE: spin_unlock_irqrestore(&hwlock->lock, *flags); - else if (mode == HWLOCK_IRQ) + break; + case HWLOCK_IRQ: spin_unlock_irq(&hwlock->lock); - else + break; + case HWLOCK_RAW: + /* Nothing to do */ + break; + default: spin_unlock(&hwlock->lock); + break; + } } EXPORT_SYMBOL_GPL(__hwspin_unlock); diff --git a/drivers/hwspinlock/hwspinlock_internal.h b/drivers/hwspinlock/hwspinlock_internal.h index d26f78b8f214..9eb6bd020dc7 100644 --- a/drivers/hwspinlock/hwspinlock_internal.h +++ b/drivers/hwspinlock/hwspinlock_internal.h @@ -1,18 +1,10 @@ +/* SPDX-License-Identifier: GPL-2.0 */ /* * Hardware spinlocks internal header * * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com * * Contact: Ohad Ben-Cohen <ohad@wizery.com> - * - * This program is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License 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. */ #ifndef __HWSPINLOCK_HWSPINLOCK_H diff --git a/drivers/hwspinlock/omap_hwspinlock.c b/drivers/hwspinlock/omap_hwspinlock.c index d897e5251c36..625844e0abef 100644 --- a/drivers/hwspinlock/omap_hwspinlock.c +++ b/drivers/hwspinlock/omap_hwspinlock.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0 /* * OMAP hardware spinlock driver * @@ -6,15 +7,6 @@ * Contact: Simon Que <sque@ti.com> * Hari Kanigeri <h-kanigeri2@ti.com> * Ohad Ben-Cohen <ohad@wizery.com> - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * 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/kernel.h> diff --git a/drivers/hwspinlock/qcom_hwspinlock.c b/drivers/hwspinlock/qcom_hwspinlock.c index fa6880b8060a..6da7447d277d 100644 --- a/drivers/hwspinlock/qcom_hwspinlock.c +++ b/drivers/hwspinlock/qcom_hwspinlock.c @@ -1,15 +1,7 @@ +// SPDX-License-Identifier: GPL-2.0 /* * Copyright (c) 2013, The Linux Foundation. All rights reserved. * Copyright (c) 2015, Sony Mobile Communications AB - * - * This software is licensed under the terms of the GNU General Public - * License version 2, as published by the Free Software Foundation, and - * may be copied, distributed, and modified under those terms. - * - * 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/hwspinlock.h> diff --git a/drivers/hwspinlock/sirf_hwspinlock.c b/drivers/hwspinlock/sirf_hwspinlock.c index cb38e487c6c4..1f625cd68c50 100644 --- a/drivers/hwspinlock/sirf_hwspinlock.c +++ b/drivers/hwspinlock/sirf_hwspinlock.c @@ -1,9 +1,8 @@ +// SPDX-License-Identifier: GPL-2.0 /* * SIRF hardware spinlock driver * * Copyright (c) 2015 Cambridge Silicon Radio Limited, a CSR plc group company. - * - * Licensed under GPLv2. */ #include <linux/kernel.h> diff --git a/drivers/hwspinlock/sprd_hwspinlock.c b/drivers/hwspinlock/sprd_hwspinlock.c index 638e64ac18f5..dc42bf51f3e6 100644 --- a/drivers/hwspinlock/sprd_hwspinlock.c +++ b/drivers/hwspinlock/sprd_hwspinlock.c @@ -1,15 +1,7 @@ +// SPDX-License-Identifier: GPL-2.0 /* * Spreadtrum hardware spinlock driver * Copyright (C) 2017 Spreadtrum - http://www.spreadtrum.com - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * 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/bitops.h> diff --git a/drivers/hwspinlock/u8500_hsem.c b/drivers/hwspinlock/u8500_hsem.c index 0128d8fb905e..572ca79d77e8 100644 --- a/drivers/hwspinlock/u8500_hsem.c +++ b/drivers/hwspinlock/u8500_hsem.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0 /* * u8500 HWSEM driver * @@ -10,15 +11,6 @@ * Simon Que <sque@ti.com> * Hari Kanigeri <h-kanigeri2@ti.com> * Ohad Ben-Cohen <ohad@wizery.com> - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * 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/module.h> |