| // SPDX-License-Identifier: GPL-2.0 |
| |
| /* |
| * Copyright (C) 2020-2021 NVIDIA CORPORATION & AFFILIATES |
| */ |
| |
| #include <linux/bitfield.h> |
| #include <linux/bitops.h> |
| #include <linux/device.h> |
| #include <linux/gpio/driver.h> |
| #include <linux/interrupt.h> |
| #include <linux/io.h> |
| #include <linux/ioport.h> |
| #include <linux/kernel.h> |
| #include <linux/mod_devicetable.h> |
| #include <linux/module.h> |
| #include <linux/platform_device.h> |
| #include <linux/pm.h> |
| #include <linux/resource.h> |
| #include <linux/spinlock.h> |
| #include <linux/types.h> |
| |
| /* |
| * There are 3 YU GPIO blocks: |
| * gpio[0]: HOST_GPIO0->HOST_GPIO31 |
| * gpio[1]: HOST_GPIO32->HOST_GPIO63 |
| * gpio[2]: HOST_GPIO64->HOST_GPIO69 |
| */ |
| #define MLXBF2_GPIO_MAX_PINS_PER_BLOCK 32 |
| |
| /* |
| * arm_gpio_lock register: |
| * bit[31] lock status: active if set |
| * bit[15:0] set lock |
| * The lock is enabled only if 0xd42f is written to this field |
| */ |
| #define YU_ARM_GPIO_LOCK_ADDR 0x2801088 |
| #define YU_ARM_GPIO_LOCK_SIZE 0x8 |
| #define YU_LOCK_ACTIVE_BIT(val) (val >> 31) |
| #define YU_ARM_GPIO_LOCK_ACQUIRE 0xd42f |
| #define YU_ARM_GPIO_LOCK_RELEASE 0x0 |
| |
| /* |
| * gpio[x] block registers and their offset |
| */ |
| #define YU_GPIO_DATAIN 0x04 |
| #define YU_GPIO_MODE1 0x08 |
| #define YU_GPIO_MODE0 0x0c |
| #define YU_GPIO_DATASET 0x14 |
| #define YU_GPIO_DATACLEAR 0x18 |
| #define YU_GPIO_CAUSE_RISE_EN 0x44 |
| #define YU_GPIO_CAUSE_FALL_EN 0x48 |
| #define YU_GPIO_MODE1_CLEAR 0x50 |
| #define YU_GPIO_MODE0_SET 0x54 |
| #define YU_GPIO_MODE0_CLEAR 0x58 |
| #define YU_GPIO_CAUSE_OR_CAUSE_EVTEN0 0x80 |
| #define YU_GPIO_CAUSE_OR_EVTEN0 0x94 |
| #define YU_GPIO_CAUSE_OR_CLRCAUSE 0x98 |
| |
| struct mlxbf2_gpio_context_save_regs { |
| u32 gpio_mode0; |
| u32 gpio_mode1; |
| }; |
| |
| /* BlueField-2 gpio block context structure. */ |
| struct mlxbf2_gpio_context { |
| struct gpio_chip gc; |
| struct irq_chip irq_chip; |
| |
| /* YU GPIO blocks address */ |
| void __iomem *gpio_io; |
| |
| struct mlxbf2_gpio_context_save_regs *csave_regs; |
| }; |
| |
| /* BlueField-2 gpio shared structure. */ |
| struct mlxbf2_gpio_param { |
| void __iomem *io; |
| struct resource *res; |
| struct mutex *lock; |
| }; |
| |
| static struct resource yu_arm_gpio_lock_res = |
| DEFINE_RES_MEM_NAMED(YU_ARM_GPIO_LOCK_ADDR, YU_ARM_GPIO_LOCK_SIZE, "YU_ARM_GPIO_LOCK"); |
| |
| static DEFINE_MUTEX(yu_arm_gpio_lock_mutex); |
| |
| static struct mlxbf2_gpio_param yu_arm_gpio_lock_param = { |
| .res = &yu_arm_gpio_lock_res, |
| .lock = &yu_arm_gpio_lock_mutex, |
| }; |
| |
| /* Request memory region and map yu_arm_gpio_lock resource */ |
| static int mlxbf2_gpio_get_lock_res(struct platform_device *pdev) |
| { |
| struct device *dev = &pdev->dev; |
| struct resource *res; |
| resource_size_t size; |
| int ret = 0; |
| |
| mutex_lock(yu_arm_gpio_lock_param.lock); |
| |
| /* Check if the memory map already exists */ |
| if (yu_arm_gpio_lock_param.io) |
| goto exit; |
| |
| res = yu_arm_gpio_lock_param.res; |
| size = resource_size(res); |
| |
| if (!devm_request_mem_region(dev, res->start, size, res->name)) { |
| ret = -EFAULT; |
| goto exit; |
| } |
| |
| yu_arm_gpio_lock_param.io = devm_ioremap(dev, res->start, size); |
| if (!yu_arm_gpio_lock_param.io) |
| ret = -ENOMEM; |
| |
| exit: |
| mutex_unlock(yu_arm_gpio_lock_param.lock); |
| |
| return ret; |
| } |
| |
| /* |
| * Acquire the YU arm_gpio_lock to be able to change the direction |
| * mode. If the lock_active bit is already set, return an error. |
| */ |
| static int mlxbf2_gpio_lock_acquire(struct mlxbf2_gpio_context *gs) |
| { |
| u32 arm_gpio_lock_val; |
| |
| mutex_lock(yu_arm_gpio_lock_param.lock); |
| spin_lock(&gs->gc.bgpio_lock); |
| |
| arm_gpio_lock_val = readl(yu_arm_gpio_lock_param.io); |
| |
| /* |
| * When lock active bit[31] is set, ModeX is write enabled |
| */ |
| if (YU_LOCK_ACTIVE_BIT(arm_gpio_lock_val)) { |
| spin_unlock(&gs->gc.bgpio_lock); |
| mutex_unlock(yu_arm_gpio_lock_param.lock); |
| return -EINVAL; |
| } |
| |
| writel(YU_ARM_GPIO_LOCK_ACQUIRE, yu_arm_gpio_lock_param.io); |
| |
| return 0; |
| } |
| |
| /* |
| * Release the YU arm_gpio_lock after changing the direction mode. |
| */ |
| static void mlxbf2_gpio_lock_release(struct mlxbf2_gpio_context *gs) |
| __releases(&gs->gc.bgpio_lock) |
| __releases(yu_arm_gpio_lock_param.lock) |
| { |
| writel(YU_ARM_GPIO_LOCK_RELEASE, yu_arm_gpio_lock_param.io); |
| spin_unlock(&gs->gc.bgpio_lock); |
| mutex_unlock(yu_arm_gpio_lock_param.lock); |
| } |
| |
| /* |
| * mode0 and mode1 are both locked by the gpio_lock field. |
| * |
| * Together, mode0 and mode1 define the gpio Mode dependeing also |
| * on Reg_DataOut. |
| * |
| * {mode1,mode0}:{Reg_DataOut=0,Reg_DataOut=1}->{DataOut=0,DataOut=1} |
| * |
| * {0,0}:Reg_DataOut{0,1}->{Z,Z} Input PAD |
| * {0,1}:Reg_DataOut{0,1}->{0,1} Full drive Output PAD |
| * {1,0}:Reg_DataOut{0,1}->{0,Z} 0-set PAD to low, 1-float |
| * {1,1}:Reg_DataOut{0,1}->{Z,1} 0-float, 1-set PAD to high |
| */ |
| |
| /* |
| * Set input direction: |
| * {mode1,mode0} = {0,0} |
| */ |
| static int mlxbf2_gpio_direction_input(struct gpio_chip *chip, |
| unsigned int offset) |
| { |
| struct mlxbf2_gpio_context *gs = gpiochip_get_data(chip); |
| int ret; |
| |
| /* |
| * Although the arm_gpio_lock was set in the probe function, check again |
| * if it is still enabled to be able to write to the ModeX registers. |
| */ |
| ret = mlxbf2_gpio_lock_acquire(gs); |
| if (ret < 0) |
| return ret; |
| |
| writel(BIT(offset), gs->gpio_io + YU_GPIO_MODE0_CLEAR); |
| writel(BIT(offset), gs->gpio_io + YU_GPIO_MODE1_CLEAR); |
| |
| mlxbf2_gpio_lock_release(gs); |
| |
| return ret; |
| } |
| |
| /* |
| * Set output direction: |
| * {mode1,mode0} = {0,1} |
| */ |
| static int mlxbf2_gpio_direction_output(struct gpio_chip *chip, |
| unsigned int offset, |
| int value) |
| { |
| struct mlxbf2_gpio_context *gs = gpiochip_get_data(chip); |
| int ret = 0; |
| |
| /* |
| * Although the arm_gpio_lock was set in the probe function, |
| * check again it is still enabled to be able to write to the |
| * ModeX registers. |
| */ |
| ret = mlxbf2_gpio_lock_acquire(gs); |
| if (ret < 0) |
| return ret; |
| |
| writel(BIT(offset), gs->gpio_io + YU_GPIO_MODE1_CLEAR); |
| writel(BIT(offset), gs->gpio_io + YU_GPIO_MODE0_SET); |
| |
| mlxbf2_gpio_lock_release(gs); |
| |
| return ret; |
| } |
| |
| static void mlxbf2_gpio_irq_enable(struct irq_data *irqd) |
| { |
| struct gpio_chip *gc = irq_data_get_irq_chip_data(irqd); |
| struct mlxbf2_gpio_context *gs = gpiochip_get_data(gc); |
| int offset = irqd_to_hwirq(irqd); |
| unsigned long flags; |
| u32 val; |
| |
| spin_lock_irqsave(&gs->gc.bgpio_lock, flags); |
| val = readl(gs->gpio_io + YU_GPIO_CAUSE_OR_CLRCAUSE); |
| val |= BIT(offset); |
| writel(val, gs->gpio_io + YU_GPIO_CAUSE_OR_CLRCAUSE); |
| |
| val = readl(gs->gpio_io + YU_GPIO_CAUSE_OR_EVTEN0); |
| val |= BIT(offset); |
| writel(val, gs->gpio_io + YU_GPIO_CAUSE_OR_EVTEN0); |
| spin_unlock_irqrestore(&gs->gc.bgpio_lock, flags); |
| } |
| |
| static void mlxbf2_gpio_irq_disable(struct irq_data *irqd) |
| { |
| struct gpio_chip *gc = irq_data_get_irq_chip_data(irqd); |
| struct mlxbf2_gpio_context *gs = gpiochip_get_data(gc); |
| int offset = irqd_to_hwirq(irqd); |
| unsigned long flags; |
| u32 val; |
| |
| spin_lock_irqsave(&gs->gc.bgpio_lock, flags); |
| val = readl(gs->gpio_io + YU_GPIO_CAUSE_OR_EVTEN0); |
| val &= ~BIT(offset); |
| writel(val, gs->gpio_io + YU_GPIO_CAUSE_OR_EVTEN0); |
| spin_unlock_irqrestore(&gs->gc.bgpio_lock, flags); |
| } |
| |
| static irqreturn_t mlxbf2_gpio_irq_handler(int irq, void *ptr) |
| { |
| struct mlxbf2_gpio_context *gs = ptr; |
| struct gpio_chip *gc = &gs->gc; |
| unsigned long pending; |
| u32 level; |
| |
| pending = readl(gs->gpio_io + YU_GPIO_CAUSE_OR_CAUSE_EVTEN0); |
| writel(pending, gs->gpio_io + YU_GPIO_CAUSE_OR_CLRCAUSE); |
| |
| for_each_set_bit(level, &pending, gc->ngpio) { |
| int gpio_irq = irq_find_mapping(gc->irq.domain, level); |
| generic_handle_irq(gpio_irq); |
| } |
| |
| return IRQ_RETVAL(pending); |
| } |
| |
| static int |
| mlxbf2_gpio_irq_set_type(struct irq_data *irqd, unsigned int type) |
| { |
| struct gpio_chip *gc = irq_data_get_irq_chip_data(irqd); |
| struct mlxbf2_gpio_context *gs = gpiochip_get_data(gc); |
| int offset = irqd_to_hwirq(irqd); |
| unsigned long flags; |
| bool fall = false; |
| bool rise = false; |
| u32 val; |
| |
| switch (type & IRQ_TYPE_SENSE_MASK) { |
| case IRQ_TYPE_EDGE_BOTH: |
| fall = true; |
| rise = true; |
| break; |
| case IRQ_TYPE_EDGE_RISING: |
| rise = true; |
| break; |
| case IRQ_TYPE_EDGE_FALLING: |
| fall = true; |
| break; |
| default: |
| return -EINVAL; |
| } |
| |
| spin_lock_irqsave(&gs->gc.bgpio_lock, flags); |
| if (fall) { |
| val = readl(gs->gpio_io + YU_GPIO_CAUSE_FALL_EN); |
| val |= BIT(offset); |
| writel(val, gs->gpio_io + YU_GPIO_CAUSE_FALL_EN); |
| } |
| |
| if (rise) { |
| val = readl(gs->gpio_io + YU_GPIO_CAUSE_RISE_EN); |
| val |= BIT(offset); |
| writel(val, gs->gpio_io + YU_GPIO_CAUSE_RISE_EN); |
| } |
| spin_unlock_irqrestore(&gs->gc.bgpio_lock, flags); |
| |
| return 0; |
| } |
| |
| /* BlueField-2 GPIO driver initialization routine. */ |
| static int |
| mlxbf2_gpio_probe(struct platform_device *pdev) |
| { |
| struct mlxbf2_gpio_context *gs; |
| struct device *dev = &pdev->dev; |
| struct gpio_irq_chip *girq; |
| struct gpio_chip *gc; |
| unsigned int npins; |
| const char *name; |
| int ret, irq; |
| |
| name = dev_name(dev); |
| |
| gs = devm_kzalloc(dev, sizeof(*gs), GFP_KERNEL); |
| if (!gs) |
| return -ENOMEM; |
| |
| /* YU GPIO block address */ |
| gs->gpio_io = devm_platform_ioremap_resource(pdev, 0); |
| if (IS_ERR(gs->gpio_io)) |
| return PTR_ERR(gs->gpio_io); |
| |
| ret = mlxbf2_gpio_get_lock_res(pdev); |
| if (ret) { |
| dev_err(dev, "Failed to get yu_arm_gpio_lock resource\n"); |
| return ret; |
| } |
| |
| if (device_property_read_u32(dev, "npins", &npins)) |
| npins = MLXBF2_GPIO_MAX_PINS_PER_BLOCK; |
| |
| gc = &gs->gc; |
| |
| ret = bgpio_init(gc, dev, 4, |
| gs->gpio_io + YU_GPIO_DATAIN, |
| gs->gpio_io + YU_GPIO_DATASET, |
| gs->gpio_io + YU_GPIO_DATACLEAR, |
| NULL, |
| NULL, |
| 0); |
| |
| if (ret) { |
| dev_err(dev, "bgpio_init failed\n"); |
| return ret; |
| } |
| |
| gc->direction_input = mlxbf2_gpio_direction_input; |
| gc->direction_output = mlxbf2_gpio_direction_output; |
| gc->ngpio = npins; |
| gc->owner = THIS_MODULE; |
| |
| irq = platform_get_irq(pdev, 0); |
| if (irq >= 0) { |
| gs->irq_chip.name = name; |
| gs->irq_chip.irq_set_type = mlxbf2_gpio_irq_set_type; |
| gs->irq_chip.irq_enable = mlxbf2_gpio_irq_enable; |
| gs->irq_chip.irq_disable = mlxbf2_gpio_irq_disable; |
| |
| girq = &gs->gc.irq; |
| girq->chip = &gs->irq_chip; |
| girq->handler = handle_simple_irq; |
| girq->default_type = IRQ_TYPE_NONE; |
| /* This will let us handle the parent IRQ in the driver */ |
| girq->num_parents = 0; |
| girq->parents = NULL; |
| girq->parent_handler = NULL; |
| |
| /* |
| * Directly request the irq here instead of passing |
| * a flow-handler because the irq is shared. |
| */ |
| ret = devm_request_irq(dev, irq, mlxbf2_gpio_irq_handler, |
| IRQF_SHARED, name, gs); |
| if (ret) { |
| dev_err(dev, "failed to request IRQ"); |
| return ret; |
| } |
| } |
| |
| platform_set_drvdata(pdev, gs); |
| |
| ret = devm_gpiochip_add_data(dev, &gs->gc, gs); |
| if (ret) { |
| dev_err(dev, "Failed adding memory mapped gpiochip\n"); |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| static int __maybe_unused mlxbf2_gpio_suspend(struct device *dev) |
| { |
| struct mlxbf2_gpio_context *gs = dev_get_drvdata(dev); |
| |
| gs->csave_regs->gpio_mode0 = readl(gs->gpio_io + |
| YU_GPIO_MODE0); |
| gs->csave_regs->gpio_mode1 = readl(gs->gpio_io + |
| YU_GPIO_MODE1); |
| |
| return 0; |
| } |
| |
| static int __maybe_unused mlxbf2_gpio_resume(struct device *dev) |
| { |
| struct mlxbf2_gpio_context *gs = dev_get_drvdata(dev); |
| |
| writel(gs->csave_regs->gpio_mode0, gs->gpio_io + |
| YU_GPIO_MODE0); |
| writel(gs->csave_regs->gpio_mode1, gs->gpio_io + |
| YU_GPIO_MODE1); |
| |
| return 0; |
| } |
| static SIMPLE_DEV_PM_OPS(mlxbf2_pm_ops, mlxbf2_gpio_suspend, mlxbf2_gpio_resume); |
| |
| static const struct acpi_device_id __maybe_unused mlxbf2_gpio_acpi_match[] = { |
| { "MLNXBF22", 0 }, |
| {}, |
| }; |
| MODULE_DEVICE_TABLE(acpi, mlxbf2_gpio_acpi_match); |
| |
| static struct platform_driver mlxbf2_gpio_driver = { |
| .driver = { |
| .name = "mlxbf2_gpio", |
| .acpi_match_table = mlxbf2_gpio_acpi_match, |
| .pm = &mlxbf2_pm_ops, |
| }, |
| .probe = mlxbf2_gpio_probe, |
| }; |
| |
| module_platform_driver(mlxbf2_gpio_driver); |
| |
| MODULE_DESCRIPTION("Mellanox BlueField-2 GPIO Driver"); |
| MODULE_AUTHOR("Asmaa Mnebhi <asmaa@nvidia.com>"); |
| MODULE_LICENSE("GPL v2"); |