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1// SPDX-License-Identifier: GPL-2.02/*3 * Spreadtrum hardware spinlock driver4 * Copyright (C) 2017 Spreadtrum - http://www.spreadtrum.com5 */6 7#include <linux/clk.h>8#include <linux/delay.h>9#include <linux/device.h>10#include <linux/hwspinlock.h>11#include <linux/io.h>12#include <linux/kernel.h>13#include <linux/module.h>14#include <linux/of.h>15#include <linux/of_device.h>16#include <linux/platform_device.h>17 18#include "hwspinlock_internal.h"19 20/* hwspinlock registers definition */21#define HWSPINLOCK_RECCTRL 0x422#define HWSPINLOCK_MASTERID(_X_) (0x80 + 0x4 * (_X_))23#define HWSPINLOCK_TOKEN(_X_) (0x800 + 0x4 * (_X_))24 25/* unlocked value */26#define HWSPINLOCK_NOTTAKEN 0x55aa10c527/* bits definition of RECCTRL reg */28#define HWSPINLOCK_USER_BITS 0x129 30/* hwspinlock number */31#define SPRD_HWLOCKS_NUM 3232 33struct sprd_hwspinlock_dev {34 void __iomem *base;35 struct clk *clk;36 struct hwspinlock_device bank;37};38 39/* try to lock the hardware spinlock */40static int sprd_hwspinlock_trylock(struct hwspinlock *lock)41{42 struct sprd_hwspinlock_dev *sprd_hwlock =43 dev_get_drvdata(lock->bank->dev);44 void __iomem *addr = lock->priv;45 int user_id, lock_id;46 47 if (!readl(addr))48 return 1;49 50 lock_id = hwlock_to_id(lock);51 /* get the hardware spinlock master/user id */52 user_id = readl(sprd_hwlock->base + HWSPINLOCK_MASTERID(lock_id));53 dev_warn(sprd_hwlock->bank.dev,54 "hwspinlock [%d] lock failed and master/user id = %d!\n",55 lock_id, user_id);56 return 0;57}58 59/* unlock the hardware spinlock */60static void sprd_hwspinlock_unlock(struct hwspinlock *lock)61{62 void __iomem *lock_addr = lock->priv;63 64 writel(HWSPINLOCK_NOTTAKEN, lock_addr);65}66 67/* The specs recommended below number as the retry delay time */68static void sprd_hwspinlock_relax(struct hwspinlock *lock)69{70 ndelay(10);71}72 73static const struct hwspinlock_ops sprd_hwspinlock_ops = {74 .trylock = sprd_hwspinlock_trylock,75 .unlock = sprd_hwspinlock_unlock,76 .relax = sprd_hwspinlock_relax,77};78 79static void sprd_hwspinlock_disable(void *data)80{81 struct sprd_hwspinlock_dev *sprd_hwlock = data;82 83 clk_disable_unprepare(sprd_hwlock->clk);84}85 86static int sprd_hwspinlock_probe(struct platform_device *pdev)87{88 struct sprd_hwspinlock_dev *sprd_hwlock;89 struct hwspinlock *lock;90 int i, ret;91 92 if (!pdev->dev.of_node)93 return -ENODEV;94 95 sprd_hwlock = devm_kzalloc(&pdev->dev,96 struct_size(sprd_hwlock, bank.lock, SPRD_HWLOCKS_NUM),97 GFP_KERNEL);98 if (!sprd_hwlock)99 return -ENOMEM;100 101 sprd_hwlock->base = devm_platform_ioremap_resource(pdev, 0);102 if (IS_ERR(sprd_hwlock->base))103 return PTR_ERR(sprd_hwlock->base);104 105 sprd_hwlock->clk = devm_clk_get(&pdev->dev, "enable");106 if (IS_ERR(sprd_hwlock->clk)) {107 dev_err(&pdev->dev, "get hwspinlock clock failed!\n");108 return PTR_ERR(sprd_hwlock->clk);109 }110 111 ret = clk_prepare_enable(sprd_hwlock->clk);112 if (ret)113 return ret;114 115 ret = devm_add_action_or_reset(&pdev->dev, sprd_hwspinlock_disable,116 sprd_hwlock);117 if (ret) {118 dev_err(&pdev->dev,119 "Failed to add hwspinlock disable action\n");120 return ret;121 }122 123 /* set the hwspinlock to record user id to identify subsystems */124 writel(HWSPINLOCK_USER_BITS, sprd_hwlock->base + HWSPINLOCK_RECCTRL);125 126 for (i = 0; i < SPRD_HWLOCKS_NUM; i++) {127 lock = &sprd_hwlock->bank.lock[i];128 lock->priv = sprd_hwlock->base + HWSPINLOCK_TOKEN(i);129 }130 131 platform_set_drvdata(pdev, sprd_hwlock);132 133 return devm_hwspin_lock_register(&pdev->dev, &sprd_hwlock->bank,134 &sprd_hwspinlock_ops, 0,135 SPRD_HWLOCKS_NUM);136}137 138static const struct of_device_id sprd_hwspinlock_of_match[] = {139 { .compatible = "sprd,hwspinlock-r3p0", },140 { /* sentinel */ }141};142MODULE_DEVICE_TABLE(of, sprd_hwspinlock_of_match);143 144static struct platform_driver sprd_hwspinlock_driver = {145 .probe = sprd_hwspinlock_probe,146 .driver = {147 .name = "sprd_hwspinlock",148 .of_match_table = sprd_hwspinlock_of_match,149 },150};151module_platform_driver(sprd_hwspinlock_driver);152 153MODULE_LICENSE("GPL v2");154MODULE_DESCRIPTION("Hardware spinlock driver for Spreadtrum");155MODULE_AUTHOR("Baolin Wang <baolin.wang@spreadtrum.com>");156MODULE_AUTHOR("Lanqing Liu <lanqing.liu@spreadtrum.com>");157MODULE_AUTHOR("Long Cheng <aiden.cheng@spreadtrum.com>");158