From a9a1a4833613b8a2e8dd79f860ea1871f17da02c Mon Sep 17 00:00:00 2001 From: Gregory CLEMENT Date: Thu, 7 Sep 2017 16:54:07 +0200 Subject: [PATCH] pinctrl: armada-37xx: Fix gpio interrupt setup Since commit dc749a09ea5e ("gpiolib: allow gpio irqchip to map irqs dynamically"), the irqs for gpio are not statically allocated during in gpiochip_irqchip_add. This driver was based on this assumption for initializing the mask associated to each interrupt this led to a NULL pointer crash in the kernel: Unable to handle kernel NULL pointer dereference at virtual address 00000000 Mem abort info: Exception class = DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000068 CM = 0, WnR = 1 [0000000000000000] user address but active_mm is swapper Internal error: Oops: 96000044 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.13.0-06657-g3b9f8ed25dbe #576 Hardware name: Marvell Armada 3720 Development Board DB-88F3720-DDR3 (DT) task: ffff80001d908000 task.stack: ffff000008068000 PC is at armada_37xx_pinctrl_probe+0x5f8/0x670 LR is at armada_37xx_pinctrl_probe+0x5e8/0x670 pc : [] lr : [] pstate: 60000045 sp : ffff00000806bb80 x29: ffff00000806bb80 x28: 0000000000000024 x27: 000000000000000c x26: 0000000000000001 x25: ffff80001efee760 x24: 0000000000000000 x23: ffff80001db6f570 x22: ffff80001db6f438 x21: 0000000000000000 x20: ffff80001d9f4810 x19: ffff80001db6f418 x18: 0000000000000000 x17: 0000000000000001 x16: 0000000000000019 x15: ffffffffffffffff x14: 0140000000000000 x13: 0000000000000000 x12: 0000000000000030 x11: 0101010101010101 x10: 0000000000000040 x9 : ffff000009923580 x8 : ffff80001d400248 x7 : ffff80001d400270 x6 : 0000000000000000 x5 : ffff80001d400248 x4 : ffff80001d400270 x3 : 0000000000000000 x2 : 0000000000000001 x1 : 0000000000000001 x0 : 0000000000000000 Process swapper/0 (pid: 1, stack limit = 0xffff000008068000) Call trace: Exception stack(0xffff00000806ba40 to 0xffff00000806bb80) ba40: 0000000000000000 0000000000000001 0000000000000001 0000000000000000 ba60: ffff80001d400270 ffff80001d400248 0000000000000000 ffff80001d400270 ba80: ffff80001d400248 ffff000009923580 0000000000000040 0101010101010101 baa0: 0000000000000030 0000000000000000 0140000000000000 ffffffffffffffff bac0: 0000000000000019 0000000000000001 0000000000000000 ffff80001db6f418 bae0: ffff80001d9f4810 0000000000000000 ffff80001db6f438 ffff80001db6f570 bb00: 0000000000000000 ffff80001efee760 0000000000000001 000000000000000c bb20: 0000000000000024 ffff00000806bb80 ffff000008e25ccc ffff00000806bb80 bb40: ffff000008e25cdc 0000000060000045 ffff00000806bb60 ffff0000081189b8 bb60: ffffffffffffffff ffff00000811cf1c ffff00000806bb80 ffff000008e25cdc [] armada_37xx_pinctrl_probe+0x5f8/0x670 [] platform_drv_probe+0x58/0xb8 [] driver_probe_device+0x22c/0x2d8 [] __driver_attach+0xbc/0xc0 [] bus_for_each_dev+0x4c/0x98 [] driver_attach+0x20/0x28 [] bus_add_driver+0x1b8/0x228 [] driver_register+0x60/0xf8 [] __platform_driver_probe+0x74/0x130 [] armada_37xx_pinctrl_driver_init+0x20/0x28 [] do_one_initcall+0x38/0x128 [] kernel_init_freeable+0x188/0x22c [] kernel_init+0x10/0x100 [] ret_from_fork+0x10/0x18 Code: f9403fa2 12001341 1100075a 9ac12041 (b9000001) ---[ end trace 8b0f4e05e1603208 ]--- This patch moves the initialization of the mask field in the irq_startup function. However some callbacks such as irq_set_type and irq_set_wake could be called before irq_startup. For those functions the mask is computed at each call which is not a issue as these functions are not located in a hot path but are used sporadically for configuration. Fixes: dc749a09ea5e ("gpiolib: allow gpio irqchip to map irqs dynamically") Cc: Signed-off-by: Gregory CLEMENT Signed-off-by: Linus Walleij --- drivers/pinctrl/mvebu/pinctrl-armada-37xx.c | 41 +++++++++++---------- 1 file changed, 22 insertions(+), 19 deletions(-) diff --git a/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c b/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c index b8b6ab072cd0..71b944748304 100644 --- a/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c +++ b/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c @@ -550,9 +550,9 @@ static int armada_37xx_irq_set_wake(struct irq_data *d, unsigned int on) spin_lock_irqsave(&info->irq_lock, flags); val = readl(info->base + reg); if (on) - val |= d->mask; + val |= (BIT(d->hwirq % GPIO_PER_REG)); else - val &= ~d->mask; + val &= ~(BIT(d->hwirq % GPIO_PER_REG)); writel(val, info->base + reg); spin_unlock_irqrestore(&info->irq_lock, flags); @@ -571,10 +571,10 @@ static int armada_37xx_irq_set_type(struct irq_data *d, unsigned int type) val = readl(info->base + reg); switch (type) { case IRQ_TYPE_EDGE_RISING: - val &= ~d->mask; + val &= ~(BIT(d->hwirq % GPIO_PER_REG)); break; case IRQ_TYPE_EDGE_FALLING: - val |= d->mask; + val |= (BIT(d->hwirq % GPIO_PER_REG)); break; default: spin_unlock_irqrestore(&info->irq_lock, flags); @@ -624,11 +624,27 @@ static void armada_37xx_irq_handler(struct irq_desc *desc) chained_irq_exit(chip, desc); } +static unsigned int armada_37xx_irq_startup(struct irq_data *d) +{ + struct gpio_chip *chip = irq_data_get_irq_chip_data(d); + int irq = d->hwirq - chip->irq_base; + /* + * The mask field is a "precomputed bitmask for accessing the + * chip registers" which was introduced for the generic + * irqchip framework. As we don't use this framework, we can + * reuse this field for our own usage. + */ + d->mask = BIT(irq % GPIO_PER_REG); + + armada_37xx_irq_unmask(d); + + return 0; +} + static int armada_37xx_irqchip_register(struct platform_device *pdev, struct armada_37xx_pinctrl *info) { struct device_node *np = info->dev->of_node; - int nrirqs = info->data->nr_pins; struct gpio_chip *gc = &info->gpio_chip; struct irq_chip *irqchip = &info->irq_chip; struct resource res; @@ -666,8 +682,8 @@ static int armada_37xx_irqchip_register(struct platform_device *pdev, irqchip->irq_unmask = armada_37xx_irq_unmask; irqchip->irq_set_wake = armada_37xx_irq_set_wake; irqchip->irq_set_type = armada_37xx_irq_set_type; + irqchip->irq_startup = armada_37xx_irq_startup; irqchip->name = info->data->name; - ret = gpiochip_irqchip_add(gc, irqchip, 0, handle_edge_irq, IRQ_TYPE_NONE); if (ret) { @@ -680,19 +696,6 @@ static int armada_37xx_irqchip_register(struct platform_device *pdev, * controller. But we do not take advantage of this and use * the chained irq with all of them. */ - for (i = 0; i < nrirqs; i++) { - struct irq_data *d = irq_get_irq_data(gc->irq_base + i); - - /* - * The mask field is a "precomputed bitmask for - * accessing the chip registers" which was introduced - * for the generic irqchip framework. As we don't use - * this framework, we can reuse this field for our own - * usage. - */ - d->mask = BIT(i % GPIO_PER_REG); - } - for (i = 0; i < nr_irq_parent; i++) { int irq = irq_of_parse_and_map(np, i); -- 2.20.1