// SPDX-License-Identifier: GPL-2.0 /* * u8500 HWSEM driver * * Copyright (C) 2010-2011 ST-Ericsson * * Implements u8500 semaphore handling for protocol 1, no interrupts. * * Author: Mathieu Poirier <[email protected]> * Heavily borrowed from the work of : * Simon Que <[email protected]> * Hari Kanigeri <[email protected]> * Ohad Ben-Cohen <[email protected]> */ #include <linux/module.h> #include <linux/delay.h> #include <linux/io.h> #include <linux/slab.h> #include <linux/spinlock.h> #include <linux/hwspinlock.h> #include <linux/platform_device.h> #include "hwspinlock_internal.h" /* * Implementation of STE's HSem protocol 1 without interrutps. * The only masterID we allow is '0x01' to force people to use * HSems for synchronisation between processors rather than processes * on the ARM core. */ #define U8500_MAX_SEMAPHORE … #define RESET_SEMAPHORE … /* * CPU ID for master running u8500 kernel. * Hswpinlocks should only be used to synchonise operations * between the Cortex A9 core and the other CPUs. Hence * forcing the masterID to a preset value. */ #define HSEM_MASTER_ID … #define HSEM_REGISTER_OFFSET … #define HSEM_CTRL_REG … #define HSEM_ICRALL … #define HSEM_PROTOCOL_1 … static int u8500_hsem_trylock(struct hwspinlock *lock) { … } static void u8500_hsem_unlock(struct hwspinlock *lock) { … } /* * u8500: what value is recommended here ? */ static void u8500_hsem_relax(struct hwspinlock *lock) { … } static const struct hwspinlock_ops u8500_hwspinlock_ops = …; static int u8500_hsem_probe(struct platform_device *pdev) { … } static void u8500_hsem_remove(struct platform_device *pdev) { … } static struct platform_driver u8500_hsem_driver = …; static int __init u8500_hsem_init(void) { … } /* board init code might need to reserve hwspinlocks for predefined purposes */ postcore_initcall(u8500_hsem_init); static void __exit u8500_hsem_exit(void) { … } module_exit(u8500_hsem_exit); MODULE_LICENSE(…) …; MODULE_DESCRIPTION(…) …; MODULE_AUTHOR(…) …;
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