forked from Minki/linux
3c938cc5ce
In case of PREEMPT_RT, there is a raw_spinlock -> spinlock dependency
as the lockdep report shows.
__irq_set_handler
irq_get_desc_buslock
__irq_get_desc_lock
raw_spin_lock_irqsave(&desc->lock, *flags); // raw spinlock get here
__irq_do_set_handler
mask_ack_irq
dwapb_irq_ack
spin_lock_irqsave(&gc->bgpio_lock, flags); // sleep able spinlock
irq_put_desc_busunlock
Replace with a raw lock to avoid BUGs. This lock is only used to access
registers, and It's safe to replace with the raw lock without bad
influence.
[ 15.090359][ T1] =============================
[ 15.090365][ T1] [ BUG: Invalid wait context ]
[ 15.090373][ T1] 5.10.59-rt52-00983-g186a6841c682-dirty #3 Not tainted
[ 15.090386][ T1] -----------------------------
[ 15.090392][ T1] swapper/0/1 is trying to lock:
[ 15.090402][ T1] 70ff00018507c188 (&gc->bgpio_lock){....}-{3:3}, at: _raw_spin_lock_irqsave+0x1c/0x28
[ 15.090470][ T1] other info that might help us debug this:
[ 15.090477][ T1] context-{5:5}
[ 15.090485][ T1] 3 locks held by swapper/0/1:
[ 15.090497][ T1] #0: c2ff0001816de1a0 (&dev->mutex){....}-{4:4}, at: __device_driver_lock+0x98/0x104
[ 15.090553][ T1] #1: ffff90001485b4b8 (irq_domain_mutex){+.+.}-{4:4}, at: irq_domain_associate+0xbc/0x6d4
[ 15.090606][ T1] #2: 4bff000185d7a8e0 (lock_class){....}-{2:2}, at: _raw_spin_lock_irqsave+0x1c/0x28
[ 15.090654][ T1] stack backtrace:
[ 15.090661][ T1] CPU: 4 PID: 1 Comm: swapper/0 Not tainted 5.10.59-rt52-00983-g186a6841c682-dirty #3
[ 15.090682][ T1] Hardware name: Horizon Robotics Journey 5 DVB (DT)
[ 15.090692][ T1] Call trace:
......
[ 15.090811][ T1] _raw_spin_lock_irqsave+0x1c/0x28
[ 15.090828][ T1] dwapb_irq_ack+0xb4/0x300
[ 15.090846][ T1] __irq_do_set_handler+0x494/0xb2c
[ 15.090864][ T1] __irq_set_handler+0x74/0x114
[ 15.090881][ T1] irq_set_chip_and_handler_name+0x44/0x58
[ 15.090900][ T1] gpiochip_irq_map+0x210/0x644
Signed-off-by: Schspa Shi <schspa@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Doug Berger <opendmb@gmail.com>
Acked-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
96 lines
2.3 KiB
C
96 lines
2.3 KiB
C
/*
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* GPIO Driver for Loongson 1 SoC
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*
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* Copyright (C) 2015-2016 Zhang, Keguang <keguang.zhang@gmail.com>
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*
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* This file is licensed under the terms of the GNU General Public
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* License version 2. This program is licensed "as is" without any
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* warranty of any kind, whether express or implied.
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*/
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#include <linux/module.h>
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#include <linux/gpio/driver.h>
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#include <linux/platform_device.h>
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#include <linux/bitops.h>
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/* Loongson 1 GPIO Register Definitions */
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#define GPIO_CFG 0x0
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#define GPIO_DIR 0x10
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#define GPIO_DATA 0x20
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#define GPIO_OUTPUT 0x30
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static void __iomem *gpio_reg_base;
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static int ls1x_gpio_request(struct gpio_chip *gc, unsigned int offset)
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{
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unsigned long flags;
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raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
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__raw_writel(__raw_readl(gpio_reg_base + GPIO_CFG) | BIT(offset),
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gpio_reg_base + GPIO_CFG);
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raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
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return 0;
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}
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static void ls1x_gpio_free(struct gpio_chip *gc, unsigned int offset)
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{
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unsigned long flags;
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raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
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__raw_writel(__raw_readl(gpio_reg_base + GPIO_CFG) & ~BIT(offset),
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gpio_reg_base + GPIO_CFG);
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raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
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}
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static int ls1x_gpio_probe(struct platform_device *pdev)
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{
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struct device *dev = &pdev->dev;
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struct gpio_chip *gc;
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int ret;
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gc = devm_kzalloc(dev, sizeof(*gc), GFP_KERNEL);
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if (!gc)
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return -ENOMEM;
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gpio_reg_base = devm_platform_ioremap_resource(pdev, 0);
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if (IS_ERR(gpio_reg_base))
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return PTR_ERR(gpio_reg_base);
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ret = bgpio_init(gc, dev, 4, gpio_reg_base + GPIO_DATA,
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gpio_reg_base + GPIO_OUTPUT, NULL,
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NULL, gpio_reg_base + GPIO_DIR, 0);
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if (ret)
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goto err;
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gc->owner = THIS_MODULE;
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gc->request = ls1x_gpio_request;
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gc->free = ls1x_gpio_free;
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gc->base = pdev->id * 32;
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ret = devm_gpiochip_add_data(dev, gc, NULL);
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if (ret)
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goto err;
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platform_set_drvdata(pdev, gc);
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dev_info(dev, "Loongson1 GPIO driver registered\n");
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return 0;
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err:
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dev_err(dev, "failed to register GPIO device\n");
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return ret;
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}
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static struct platform_driver ls1x_gpio_driver = {
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.probe = ls1x_gpio_probe,
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.driver = {
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.name = "ls1x-gpio",
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},
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};
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module_platform_driver(ls1x_gpio_driver);
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MODULE_AUTHOR("Kelvin Cheung <keguang.zhang@gmail.com>");
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MODULE_DESCRIPTION("Loongson1 GPIO driver");
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MODULE_LICENSE("GPL");
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