Commit 392035c8 authored by Wolfram Sang's avatar Wolfram Sang Committed by Bjorn Andersson
Browse files

hwspinlock: u8500: delete driver 



The U8500 platform was converted to DT around 2013 and is DT only
meanwhile. This driver has never been converted to a DT driver, so it
clearly hasn't been used since then. To ease upcoming refactoring in the
hwspinlock subsystem, remove this obsolete driver.

Signed-off-by: default avatarWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: default avatarLinus Walleij <linusw@kernel.org>
Acked-by: default avatarAndy Shevchenko <andriy.shevchenko@intel.com>
Link: https://lore.kernel.org/r/20260401071141.4718-2-wsa+renesas@sang-engineering.com


Signed-off-by: default avatarBjorn Andersson <andersson@kernel.org>
parent 6de23f81

MAINTAINERS

+0 −1
Original line number Diff line number Diff line
@@ -3158,7 +3158,6 @@ F: drivers/clocksource/clksrc-dbx500-prcmu.c 
F:	drivers/dma/ste_dma40*

F:	drivers/pmdomain/st/ste-ux500-pm-domain.c

F:	drivers/gpio/gpio-nomadik.c

F:	drivers/hwspinlock/u8500_hsem.c

F:	drivers/i2c/busses/i2c-nomadik.c

F:	drivers/iio/adc/ab8500-gpadc.c

F:	drivers/mfd/ab8500*

arch/arm/configs/u8500_defconfig

+0 −1
Original line number Diff line number Diff line
@@ -148,7 +148,6 @@ CONFIG_RTC_DRV_PL031=y 
CONFIG_DMADEVICES=y

CONFIG_STE_DMA40=y

CONFIG_HWSPINLOCK=y

CONFIG_HSEM_U8500=y

CONFIG_EXTCON_FSA9480=y

CONFIG_IIO=y

CONFIG_IIO_SW_TRIGGER=y

drivers/hwspinlock/Kconfig

+0 −10
Original line number Diff line number Diff line
@@ -53,14 +53,4 @@ config HWSPINLOCK_SUN6I 


	  If unsure, say N.



config HSEM_U8500

	tristate "STE Hardware Semaphore functionality"

	depends on ARCH_U8500 || COMPILE_TEST

	help

	  Say y here to support the STE Hardware Semaphore functionality, which

	  provides a synchronisation mechanism for the various processor on the

	  SoC.



	  If unsure, say N.



endif # HWSPINLOCK

drivers/hwspinlock/Makefile

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@@ -9,4 +9,3 @@ obj-$(CONFIG_HWSPINLOCK_QCOM) += qcom_hwspinlock.o 
obj-$(CONFIG_HWSPINLOCK_SPRD)		+= sprd_hwspinlock.o

obj-$(CONFIG_HWSPINLOCK_STM32)		+= stm32_hwspinlock.o

obj-$(CONFIG_HWSPINLOCK_SUN6I)		+= sun6i_hwspinlock.o
 
obj-$(CONFIG_HSEM_U8500)		+= u8500_hsem.o

drivers/hwspinlock/u8500_hsem.c

deleted100644 → 0
+0 −155
Original line number Diff line number Diff line 
// 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 <mathieu.poirier@linaro.org>

 * Heavily borrowed from the work of :

 *   Simon Que <sque@ti.com>

 *   Hari Kanigeri <h-kanigeri2@ti.com>

 *   Ohad Ben-Cohen <ohad@wizery.com>

 */



#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		32	/* a total of 32 semaphore */

#define RESET_SEMAPHORE			(0)	/* free */



/*

 * 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			0x01



#define HSEM_REGISTER_OFFSET		0x08



#define HSEM_CTRL_REG			0x00

#define HSEM_ICRALL			0x90

#define HSEM_PROTOCOL_1			0x01



static int u8500_hsem_trylock(struct hwspinlock *lock)

{

	void __iomem *lock_addr = lock->priv;



	writel(HSEM_MASTER_ID, lock_addr);



	/* get only first 4 bit and compare to masterID.

	 * if equal, we have the semaphore, otherwise

	 * someone else has it.

	 */

	return (HSEM_MASTER_ID == (0x0F & readl(lock_addr)));

}



static void u8500_hsem_unlock(struct hwspinlock *lock)

{

	void __iomem *lock_addr = lock->priv;



	/* release the lock by writing 0 to it */

	writel(RESET_SEMAPHORE, lock_addr);

}



/*

 * u8500: what value is recommended here ?

 */

static void u8500_hsem_relax(struct hwspinlock *lock)

{

	ndelay(50);

}



static const struct hwspinlock_ops u8500_hwspinlock_ops = {

	.trylock	= u8500_hsem_trylock,

	.unlock		= u8500_hsem_unlock,

	.relax		= u8500_hsem_relax,

};



static int u8500_hsem_probe(struct platform_device *pdev)

{

	struct hwspinlock_pdata *pdata = pdev->dev.platform_data;

	struct hwspinlock_device *bank;

	struct hwspinlock *hwlock;

	void __iomem *io_base;

	int i, num_locks = U8500_MAX_SEMAPHORE;

	ulong val;



	if (!pdata)

		return -ENODEV;



	io_base = devm_platform_ioremap_resource(pdev, 0);

	if (IS_ERR(io_base))

		return PTR_ERR(io_base);



	/* make sure protocol 1 is selected */

	val = readl(io_base + HSEM_CTRL_REG);

	writel((val & ~HSEM_PROTOCOL_1), io_base + HSEM_CTRL_REG);



	/* clear all interrupts */

	writel(0xFFFF, io_base + HSEM_ICRALL);



	bank = devm_kzalloc(&pdev->dev, struct_size(bank, lock, num_locks),

			    GFP_KERNEL);

	if (!bank)

		return -ENOMEM;



	platform_set_drvdata(pdev, bank);



	for (i = 0, hwlock = &bank->lock[0]; i < num_locks; i++, hwlock++)

		hwlock->priv = io_base + HSEM_REGISTER_OFFSET + sizeof(u32) * i;



	return devm_hwspin_lock_register(&pdev->dev, bank,

					 &u8500_hwspinlock_ops,

					 pdata->base_id, num_locks);

}



static void u8500_hsem_remove(struct platform_device *pdev)

{

	struct hwspinlock_device *bank = platform_get_drvdata(pdev);

	void __iomem *io_base = bank->lock[0].priv - HSEM_REGISTER_OFFSET;



	/* clear all interrupts */

	writel(0xFFFF, io_base + HSEM_ICRALL);

}



static struct platform_driver u8500_hsem_driver = {

	.probe		= u8500_hsem_probe,

	.remove		= u8500_hsem_remove,

	.driver		= {

		.name	= "u8500_hsem",

	},

};



static int __init u8500_hsem_init(void)

{

	return platform_driver_register(&u8500_hsem_driver);

}

/* board init code might need to reserve hwspinlocks for predefined purposes */

postcore_initcall(u8500_hsem_init);



static void __exit u8500_hsem_exit(void)

{

	platform_driver_unregister(&u8500_hsem_driver);

}

module_exit(u8500_hsem_exit);



MODULE_LICENSE("GPL v2");

MODULE_DESCRIPTION("Hardware Spinlock driver for u8500");

MODULE_AUTHOR("Mathieu Poirier <mathieu.poirier@linaro.org>");