[v3,5/6] gpio: sifive: Add GPIO driver for SiFive SoCs
diff mbox series

Message ID 1574661437-28486-6-git-send-email-yash.shah@sifive.com
State New
Headers show
Series
  • GPIO & Hierarchy IRQ support for HiFive Unleashed
Related show

Commit Message

Yash Shah Nov. 25, 2019, 5:58 a.m. UTC
Adds the GPIO driver for SiFive RISC-V SoCs.

Signed-off-by: Wesley W. Terpstra <wesley@sifive.com>
[Atish: Various fixes and code cleanup]
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Yash Shah <yash.shah@sifive.com>
---
 drivers/gpio/Kconfig       |   9 ++
 drivers/gpio/Makefile      |   1 +
 drivers/gpio/gpio-sifive.c | 252 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 262 insertions(+)
 create mode 100644 drivers/gpio/gpio-sifive.c

Comments

Bartosz Golaszewski Nov. 25, 2019, 2:02 p.m. UTC | #1
pon., 25 lis 2019 o 06:58 Yash Shah <yash.shah@sifive.com> napisaƂ(a):
>
> Adds the GPIO driver for SiFive RISC-V SoCs.
>
> Signed-off-by: Wesley W. Terpstra <wesley@sifive.com>
> [Atish: Various fixes and code cleanup]
> Signed-off-by: Atish Patra <atish.patra@wdc.com>
> Signed-off-by: Yash Shah <yash.shah@sifive.com>
> ---
>  drivers/gpio/Kconfig       |   9 ++
>  drivers/gpio/Makefile      |   1 +
>  drivers/gpio/gpio-sifive.c | 252 +++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 262 insertions(+)
>  create mode 100644 drivers/gpio/gpio-sifive.c
>
> diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
> index 38e096e..05e8a41 100644
> --- a/drivers/gpio/Kconfig
> +++ b/drivers/gpio/Kconfig
> @@ -453,6 +453,15 @@ config GPIO_SAMA5D2_PIOBU
>           The difference from regular GPIOs is that they
>           maintain their value during backup/self-refresh.
>
> +config GPIO_SIFIVE
> +       bool "SiFive GPIO support"
> +       depends on OF_GPIO
> +       select GPIO_GENERIC
> +       select GPIOLIB_IRQCHIP
> +       select REGMAP_MMIO
> +       help
> +         Say yes here to support the GPIO device on SiFive SoCs.
> +
>  config GPIO_SIOX
>         tristate "SIOX GPIO support"
>         depends on SIOX
> diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
> index d2fd19c..bf7984e 100644
> --- a/drivers/gpio/Makefile
> +++ b/drivers/gpio/Makefile
> @@ -121,6 +121,7 @@ obj-$(CONFIG_ARCH_SA1100)           += gpio-sa1100.o
>  obj-$(CONFIG_GPIO_SAMA5D2_PIOBU)       += gpio-sama5d2-piobu.o
>  obj-$(CONFIG_GPIO_SCH311X)             += gpio-sch311x.o
>  obj-$(CONFIG_GPIO_SCH)                 += gpio-sch.o
> +obj-$(CONFIG_GPIO_SIFIVE)              += gpio-sifive.o
>  obj-$(CONFIG_GPIO_SIOX)                        += gpio-siox.o
>  obj-$(CONFIG_GPIO_SODAVILLE)           += gpio-sodaville.o
>  obj-$(CONFIG_GPIO_SPEAR_SPICS)         += gpio-spear-spics.o
> diff --git a/drivers/gpio/gpio-sifive.c b/drivers/gpio/gpio-sifive.c
> new file mode 100644
> index 0000000..147a1bd
> --- /dev/null
> +++ b/drivers/gpio/gpio-sifive.c
> @@ -0,0 +1,252 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2019 SiFive
> + */
> +
> +#include <linux/bitops.h>
> +#include <linux/device.h>
> +#include <linux/errno.h>
> +#include <linux/of_irq.h>
> +#include <linux/gpio/driver.h>
> +#include <linux/init.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +#include <linux/spinlock.h>
> +#include <linux/regmap.h>
> +
> +#define SIFIVE_GPIO_INPUT_VAL  0x00
> +#define SIFIVE_GPIO_INPUT_EN   0x04
> +#define SIFIVE_GPIO_OUTPUT_EN  0x08
> +#define SIFIVE_GPIO_OUTPUT_VAL 0x0C
> +#define SIFIVE_GPIO_RISE_IE    0x18
> +#define SIFIVE_GPIO_RISE_IP    0x1C
> +#define SIFIVE_GPIO_FALL_IE    0x20
> +#define SIFIVE_GPIO_FALL_IP    0x24
> +#define SIFIVE_GPIO_HIGH_IE    0x28
> +#define SIFIVE_GPIO_HIGH_IP    0x2C
> +#define SIFIVE_GPIO_LOW_IE     0x30
> +#define SIFIVE_GPIO_LOW_IP     0x34
> +#define SIFIVE_GPIO_OUTPUT_XOR 0x40
> +
> +#define SIFIVE_GPIO_MAX                32
> +#define SIFIVE_GPIO_IRQ_OFFSET 7
> +
> +struct sifive_gpio {
> +       void __iomem            *base;
> +       struct gpio_chip        gc;
> +       struct regmap           *regs;
> +       u32                     irq_state;
> +       unsigned int            trigger[SIFIVE_GPIO_MAX];
> +       unsigned int            irq_parent[SIFIVE_GPIO_MAX];
> +};
> +
> +static void sifive_gpio_set_ie(struct sifive_gpio *chip, unsigned int offset)
> +{
> +       unsigned long flags;
> +       unsigned int trigger;
> +
> +       spin_lock_irqsave(&chip->gc.bgpio_lock, flags);
> +       trigger = (chip->irq_state & BIT(offset)) ? chip->trigger[offset] : 0;
> +       regmap_update_bits(chip->regs, SIFIVE_GPIO_RISE_IE, BIT(offset),
> +                          (trigger & IRQ_TYPE_EDGE_RISING) ? BIT(offset) : 0);
> +       regmap_update_bits(chip->regs, SIFIVE_GPIO_FALL_IE, BIT(offset),
> +                          (trigger & IRQ_TYPE_EDGE_FALLING) ? BIT(offset) : 0);
> +       regmap_update_bits(chip->regs, SIFIVE_GPIO_HIGH_IE, BIT(offset),
> +                          (trigger & IRQ_TYPE_LEVEL_HIGH) ? BIT(offset) : 0);
> +       regmap_update_bits(chip->regs, SIFIVE_GPIO_LOW_IE, BIT(offset),
> +                          (trigger & IRQ_TYPE_LEVEL_LOW) ? BIT(offset) : 0);
> +       spin_unlock_irqrestore(&chip->gc.bgpio_lock, flags);
> +}
> +
> +static int sifive_gpio_irq_set_type(struct irq_data *d, unsigned int trigger)
> +{
> +       struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
> +       struct sifive_gpio *chip = gpiochip_get_data(gc);
> +       int offset = irqd_to_hwirq(d);
> +
> +       if (offset < 0 || offset >= gc->ngpio)
> +               return -EINVAL;
> +
> +       chip->trigger[offset] = trigger;
> +       sifive_gpio_set_ie(chip, offset);
> +       return 0;
> +}
> +
> +static void sifive_gpio_irq_enable(struct irq_data *d)
> +{
> +       struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
> +       struct sifive_gpio *chip = gpiochip_get_data(gc);
> +       int offset = irqd_to_hwirq(d) % SIFIVE_GPIO_MAX;
> +       u32 bit = BIT(offset);
> +       unsigned long flags;
> +
> +       irq_chip_enable_parent(d);
> +
> +       /* Switch to input */
> +       gc->direction_input(gc, offset);
> +
> +       spin_lock_irqsave(&gc->bgpio_lock, flags);
> +       /* Clear any sticky pending interrupts */
> +       regmap_write(chip->regs, SIFIVE_GPIO_RISE_IP, bit);
> +       regmap_write(chip->regs, SIFIVE_GPIO_FALL_IP, bit);
> +       regmap_write(chip->regs, SIFIVE_GPIO_HIGH_IP, bit);
> +       regmap_write(chip->regs, SIFIVE_GPIO_LOW_IP, bit);
> +       spin_unlock_irqrestore(&gc->bgpio_lock, flags);
> +
> +       /* Enable interrupts */
> +       assign_bit(offset, (unsigned long *)&chip->irq_state, 1);
> +       sifive_gpio_set_ie(chip, offset);
> +}
> +
> +static void sifive_gpio_irq_disable(struct irq_data *d)
> +{
> +       struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
> +       struct sifive_gpio *chip = gpiochip_get_data(gc);
> +       int offset = irqd_to_hwirq(d) % SIFIVE_GPIO_MAX;
> +
> +       assign_bit(offset, (unsigned long *)&chip->irq_state, 0);
> +       sifive_gpio_set_ie(chip, offset);
> +       irq_chip_disable_parent(d);
> +}
> +
> +static void sifive_gpio_irq_eoi(struct irq_data *d)
> +{
> +       struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
> +       struct sifive_gpio *chip = gpiochip_get_data(gc);
> +       int offset = irqd_to_hwirq(d) % SIFIVE_GPIO_MAX;
> +       u32 bit = BIT(offset);
> +       unsigned long flags;
> +
> +       spin_lock_irqsave(&gc->bgpio_lock, flags);
> +       /* Clear all pending interrupts */
> +       regmap_write(chip->regs, SIFIVE_GPIO_RISE_IP, bit);
> +       regmap_write(chip->regs, SIFIVE_GPIO_FALL_IP, bit);
> +       regmap_write(chip->regs, SIFIVE_GPIO_HIGH_IP, bit);
> +       regmap_write(chip->regs, SIFIVE_GPIO_LOW_IP, bit);
> +       spin_unlock_irqrestore(&gc->bgpio_lock, flags);
> +
> +       irq_chip_eoi_parent(d);
> +}
> +
> +static struct irq_chip sifive_gpio_irqchip = {
> +       .name           = "sifive-gpio",
> +       .irq_set_type   = sifive_gpio_irq_set_type,
> +       .irq_mask       = irq_chip_mask_parent,
> +       .irq_unmask     = irq_chip_unmask_parent,
> +       .irq_enable     = sifive_gpio_irq_enable,
> +       .irq_disable    = sifive_gpio_irq_disable,
> +       .irq_eoi        = sifive_gpio_irq_eoi,
> +};
> +
> +static int sifive_gpio_child_to_parent_hwirq(struct gpio_chip *gc,
> +                                            unsigned int child,
> +                                            unsigned int child_type,
> +                                            unsigned int *parent,
> +                                            unsigned int *parent_type)
> +{
> +       *parent_type = IRQ_TYPE_NONE;
> +       *parent = child + SIFIVE_GPIO_IRQ_OFFSET;
> +       return 0;
> +}
> +
> +static const struct regmap_config sifive_gpio_regmap_config = {
> +       .reg_bits = 32,
> +       .reg_stride = 4,
> +       .val_bits = 32,
> +       .fast_io = true,
> +       .disable_locking = true,
> +};
> +
> +static int sifive_gpio_probe(struct platform_device *pdev)
> +{
> +       struct device *dev = &pdev->dev;
> +       struct device_node *node = pdev->dev.of_node;
> +       struct device_node *irq_parent;
> +       struct irq_domain *parent;
> +       struct gpio_irq_chip *girq;
> +       struct sifive_gpio *chip;
> +       int ret, ngpio;
> +
> +       chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
> +       if (!chip)
> +               return -ENOMEM;
> +
> +       chip->base = devm_platform_ioremap_resource(pdev, 0);
> +       if (IS_ERR(chip->base)) {
> +               dev_err(dev, "failed to allocate device memory\n");
> +               return PTR_ERR(chip->base);
> +       }
> +
> +       chip->regs = devm_regmap_init_mmio(dev, chip->base,
> +                                          &sifive_gpio_regmap_config);
> +       if (IS_ERR(chip->regs))
> +               return PTR_ERR(chip->regs);
> +
> +       ngpio = of_irq_count(node);
> +       if (ngpio >= SIFIVE_GPIO_MAX) {
> +               dev_err(dev, "Too many GPIO interrupts (max=%d)\n",
> +                       SIFIVE_GPIO_MAX);
> +               return -ENXIO;
> +       }
> +
> +       irq_parent = of_irq_find_parent(node);
> +       if (!irq_parent) {
> +               dev_err(dev, "no IRQ parent node\n");
> +               return -ENODEV;
> +       }
> +       parent = irq_find_host(irq_parent);
> +       if (!parent) {
> +               dev_err(dev, "no IRQ parent domain\n");
> +               return -ENODEV;
> +       }
> +
> +       ret = bgpio_init(&chip->gc, dev, 4,
> +                        chip->base + SIFIVE_GPIO_INPUT_VAL,
> +                        chip->base + SIFIVE_GPIO_OUTPUT_VAL,
> +                        NULL,
> +                        chip->base + SIFIVE_GPIO_OUTPUT_EN,
> +                        chip->base + SIFIVE_GPIO_INPUT_EN,
> +                        0);
> +       if (ret) {
> +               dev_err(dev, "unable to init generic GPIO\n");
> +               return ret;
> +       }
> +
> +       /* Disable all GPIO interrupts before enabling parent interrupts */
> +       regmap_write(chip->regs, SIFIVE_GPIO_RISE_IE, 0);
> +       regmap_write(chip->regs, SIFIVE_GPIO_FALL_IE, 0);
> +       regmap_write(chip->regs, SIFIVE_GPIO_HIGH_IE, 0);
> +       regmap_write(chip->regs, SIFIVE_GPIO_LOW_IE, 0);
> +       chip->irq_state = 0;
> +
> +       chip->gc.base = -1;
> +       chip->gc.ngpio = ngpio;
> +       chip->gc.label = dev_name(dev);
> +       chip->gc.parent = dev;
> +       chip->gc.owner = THIS_MODULE;
> +       girq = &chip->gc.irq;
> +       girq->chip = &sifive_gpio_irqchip;
> +       girq->fwnode = of_node_to_fwnode(node);
> +       girq->parent_domain = parent;
> +       girq->child_to_parent_hwirq = sifive_gpio_child_to_parent_hwirq;
> +       girq->handler = handle_bad_irq;
> +       girq->default_type = IRQ_TYPE_NONE;
> +
> +       platform_set_drvdata(pdev, chip);
> +       return gpiochip_add_data(&chip->gc, chip);
> +}
> +
> +static const struct of_device_id sifive_gpio_match[] = {
> +       { .compatible = "sifive,gpio0" },
> +       { .compatible = "sifive,fu540-c000-gpio" },
> +       { },
> +};
> +
> +static struct platform_driver sifive_gpio_driver = {
> +       .probe          = sifive_gpio_probe,
> +       .driver = {
> +               .name   = "sifive_gpio",
> +               .of_match_table = of_match_ptr(sifive_gpio_match),
> +       },
> +};
> +builtin_platform_driver(sifive_gpio_driver)
> --
> 2.7.4
>

Reviewed-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Linus Walleij Nov. 28, 2019, 12:20 p.m. UTC | #2
On Mon, Nov 25, 2019 at 6:58 AM Yash Shah <yash.shah@sifive.com> wrote:

> Adds the GPIO driver for SiFive RISC-V SoCs.
>
> Signed-off-by: Wesley W. Terpstra <wesley@sifive.com>
> [Atish: Various fixes and code cleanup]
> Signed-off-by: Atish Patra <atish.patra@wdc.com>
> Signed-off-by: Yash Shah <yash.shah@sifive.com>

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

I suppose Marc will merge all patches into the irqchip tree
as they are logically dependent? If you want the GPIO bindings
and this driver directly merged (no deps) then I can do that
as well.

Yours,
Linus Walleij
Yash Shah Nov. 29, 2019, 6:27 a.m. UTC | #3
> -----Original Message-----
> From: Linus Walleij <linus.walleij@linaro.org>
> Sent: 28 November 2019 17:50
> To: Yash Shah <yash.shah@sifive.com>
> Cc: bgolaszewski@baylibre.com; robh+dt@kernel.org;
> mark.rutland@arm.com; palmer@dabbelt.com; Paul Walmsley ( Sifive)
> <paul.walmsley@sifive.com>; aou@eecs.berkeley.edu; tglx@linutronix.de;
> jason@lakedaemon.net; maz@kernel.org; bmeng.cn@gmail.com;
> atish.patra@wdc.com; Sagar Kadam <sagar.kadam@sifive.com>; linux-
> gpio@vger.kernel.org; devicetree@vger.kernel.org; linux-
> riscv@lists.infradead.org; linux-kernel@vger.kernel.org; Sachin Ghadi
> <sachin.ghadi@sifive.com>
> Subject: Re: [PATCH v3 5/6] gpio: sifive: Add GPIO driver for SiFive SoCs
> 
> On Mon, Nov 25, 2019 at 6:58 AM Yash Shah <yash.shah@sifive.com> wrote:
> 
> > Adds the GPIO driver for SiFive RISC-V SoCs.
> >
> > Signed-off-by: Wesley W. Terpstra <wesley@sifive.com>
> > [Atish: Various fixes and code cleanup]
> > Signed-off-by: Atish Patra <atish.patra@wdc.com>
> > Signed-off-by: Yash Shah <yash.shah@sifive.com>
> 
> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
> 
> I suppose Marc will merge all patches into the irqchip tree as they are logically
> dependent? If you want the GPIO bindings and this driver directly merged
> (no deps) then I can do that as well.

Yes, the GPIO driver have logical dependency on irqchip patches. It is best if Marc merges all the patches into the irqchip tree.

@Marc Zyngier, Are you going to merge all the patches into the irqchip tree?

- Yash
Marc Zyngier Nov. 29, 2019, 9:12 a.m. UTC | #4
On 2019-11-29 06:27, Yash Shah wrote:
>> -----Original Message-----
>> From: Linus Walleij <linus.walleij@linaro.org>
>> Sent: 28 November 2019 17:50
>> To: Yash Shah <yash.shah@sifive.com>
>> Cc: bgolaszewski@baylibre.com; robh+dt@kernel.org;
>> mark.rutland@arm.com; palmer@dabbelt.com; Paul Walmsley ( Sifive)
>> <paul.walmsley@sifive.com>; aou@eecs.berkeley.edu; 
>> tglx@linutronix.de;
>> jason@lakedaemon.net; maz@kernel.org; bmeng.cn@gmail.com;
>> atish.patra@wdc.com; Sagar Kadam <sagar.kadam@sifive.com>; linux-
>> gpio@vger.kernel.org; devicetree@vger.kernel.org; linux-
>> riscv@lists.infradead.org; linux-kernel@vger.kernel.org; Sachin 
>> Ghadi
>> <sachin.ghadi@sifive.com>
>> Subject: Re: [PATCH v3 5/6] gpio: sifive: Add GPIO driver for SiFive 
>> SoCs
>>
>> On Mon, Nov 25, 2019 at 6:58 AM Yash Shah <yash.shah@sifive.com> 
>> wrote:
>>
>> > Adds the GPIO driver for SiFive RISC-V SoCs.
>> >
>> > Signed-off-by: Wesley W. Terpstra <wesley@sifive.com>
>> > [Atish: Various fixes and code cleanup]
>> > Signed-off-by: Atish Patra <atish.patra@wdc.com>
>> > Signed-off-by: Yash Shah <yash.shah@sifive.com>
>>
>> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
>>
>> I suppose Marc will merge all patches into the irqchip tree as they 
>> are logically
>> dependent? If you want the GPIO bindings and this driver directly 
>> merged
>> (no deps) then I can do that as well.
>
> Yes, the GPIO driver have logical dependency on irqchip patches. It
> is best if Marc merges all the patches into the irqchip tree.
>
> @Marc Zyngier, Are you going to merge all the patches into the 
> irqchip tree?

I'm happy to pick this up, but that's definitely 5.6 material as
I stopped collecting new 5.5 features a couple of weeks ago.

Thanks,

         M.
Palmer Dabbelt Dec. 7, 2019, 1:07 a.m. UTC | #5
On Fri, 29 Nov 2019 01:12:10 PST (-0800), maz@kernel.org wrote:
> On 2019-11-29 06:27, Yash Shah wrote:
>>> -----Original Message-----
>>> From: Linus Walleij <linus.walleij@linaro.org>
>>> Sent: 28 November 2019 17:50
>>> To: Yash Shah <yash.shah@sifive.com>
>>> Cc: bgolaszewski@baylibre.com; robh+dt@kernel.org;
>>> mark.rutland@arm.com; palmer@dabbelt.com; Paul Walmsley ( Sifive)
>>> <paul.walmsley@sifive.com>; aou@eecs.berkeley.edu;
>>> tglx@linutronix.de;
>>> jason@lakedaemon.net; maz@kernel.org; bmeng.cn@gmail.com;
>>> atish.patra@wdc.com; Sagar Kadam <sagar.kadam@sifive.com>; linux-
>>> gpio@vger.kernel.org; devicetree@vger.kernel.org; linux-
>>> riscv@lists.infradead.org; linux-kernel@vger.kernel.org; Sachin
>>> Ghadi
>>> <sachin.ghadi@sifive.com>
>>> Subject: Re: [PATCH v3 5/6] gpio: sifive: Add GPIO driver for SiFive
>>> SoCs
>>>
>>> On Mon, Nov 25, 2019 at 6:58 AM Yash Shah <yash.shah@sifive.com>
>>> wrote:
>>>
>>> > Adds the GPIO driver for SiFive RISC-V SoCs.
>>> >
>>> > Signed-off-by: Wesley W. Terpstra <wesley@sifive.com>
>>> > [Atish: Various fixes and code cleanup]
>>> > Signed-off-by: Atish Patra <atish.patra@wdc.com>
>>> > Signed-off-by: Yash Shah <yash.shah@sifive.com>
>>>
>>> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
>>>
>>> I suppose Marc will merge all patches into the irqchip tree as they
>>> are logically
>>> dependent? If you want the GPIO bindings and this driver directly
>>> merged
>>> (no deps) then I can do that as well.
>>
>> Yes, the GPIO driver have logical dependency on irqchip patches. It
>> is best if Marc merges all the patches into the irqchip tree.
>>
>> @Marc Zyngier, Are you going to merge all the patches into the
>> irqchip tree?
>
> I'm happy to pick this up, but that's definitely 5.6 material as
> I stopped collecting new 5.5 features a couple of weeks ago.

Thanks!

Patch
diff mbox series

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 38e096e..05e8a41 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -453,6 +453,15 @@  config GPIO_SAMA5D2_PIOBU
 	  The difference from regular GPIOs is that they
 	  maintain their value during backup/self-refresh.
 
+config GPIO_SIFIVE
+	bool "SiFive GPIO support"
+	depends on OF_GPIO
+	select GPIO_GENERIC
+	select GPIOLIB_IRQCHIP
+	select REGMAP_MMIO
+	help
+	  Say yes here to support the GPIO device on SiFive SoCs.
+
 config GPIO_SIOX
 	tristate "SIOX GPIO support"
 	depends on SIOX
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index d2fd19c..bf7984e 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -121,6 +121,7 @@  obj-$(CONFIG_ARCH_SA1100)		+= gpio-sa1100.o
 obj-$(CONFIG_GPIO_SAMA5D2_PIOBU)	+= gpio-sama5d2-piobu.o
 obj-$(CONFIG_GPIO_SCH311X)		+= gpio-sch311x.o
 obj-$(CONFIG_GPIO_SCH)			+= gpio-sch.o
+obj-$(CONFIG_GPIO_SIFIVE)		+= gpio-sifive.o
 obj-$(CONFIG_GPIO_SIOX)			+= gpio-siox.o
 obj-$(CONFIG_GPIO_SODAVILLE)		+= gpio-sodaville.o
 obj-$(CONFIG_GPIO_SPEAR_SPICS)		+= gpio-spear-spics.o
diff --git a/drivers/gpio/gpio-sifive.c b/drivers/gpio/gpio-sifive.c
new file mode 100644
index 0000000..147a1bd
--- /dev/null
+++ b/drivers/gpio/gpio-sifive.c
@@ -0,0 +1,252 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 SiFive
+ */
+
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/of_irq.h>
+#include <linux/gpio/driver.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/regmap.h>
+
+#define SIFIVE_GPIO_INPUT_VAL	0x00
+#define SIFIVE_GPIO_INPUT_EN	0x04
+#define SIFIVE_GPIO_OUTPUT_EN	0x08
+#define SIFIVE_GPIO_OUTPUT_VAL	0x0C
+#define SIFIVE_GPIO_RISE_IE	0x18
+#define SIFIVE_GPIO_RISE_IP	0x1C
+#define SIFIVE_GPIO_FALL_IE	0x20
+#define SIFIVE_GPIO_FALL_IP	0x24
+#define SIFIVE_GPIO_HIGH_IE	0x28
+#define SIFIVE_GPIO_HIGH_IP	0x2C
+#define SIFIVE_GPIO_LOW_IE	0x30
+#define SIFIVE_GPIO_LOW_IP	0x34
+#define SIFIVE_GPIO_OUTPUT_XOR	0x40
+
+#define SIFIVE_GPIO_MAX		32
+#define SIFIVE_GPIO_IRQ_OFFSET	7
+
+struct sifive_gpio {
+	void __iomem		*base;
+	struct gpio_chip	gc;
+	struct regmap		*regs;
+	u32			irq_state;
+	unsigned int		trigger[SIFIVE_GPIO_MAX];
+	unsigned int		irq_parent[SIFIVE_GPIO_MAX];
+};
+
+static void sifive_gpio_set_ie(struct sifive_gpio *chip, unsigned int offset)
+{
+	unsigned long flags;
+	unsigned int trigger;
+
+	spin_lock_irqsave(&chip->gc.bgpio_lock, flags);
+	trigger = (chip->irq_state & BIT(offset)) ? chip->trigger[offset] : 0;
+	regmap_update_bits(chip->regs, SIFIVE_GPIO_RISE_IE, BIT(offset),
+			   (trigger & IRQ_TYPE_EDGE_RISING) ? BIT(offset) : 0);
+	regmap_update_bits(chip->regs, SIFIVE_GPIO_FALL_IE, BIT(offset),
+			   (trigger & IRQ_TYPE_EDGE_FALLING) ? BIT(offset) : 0);
+	regmap_update_bits(chip->regs, SIFIVE_GPIO_HIGH_IE, BIT(offset),
+			   (trigger & IRQ_TYPE_LEVEL_HIGH) ? BIT(offset) : 0);
+	regmap_update_bits(chip->regs, SIFIVE_GPIO_LOW_IE, BIT(offset),
+			   (trigger & IRQ_TYPE_LEVEL_LOW) ? BIT(offset) : 0);
+	spin_unlock_irqrestore(&chip->gc.bgpio_lock, flags);
+}
+
+static int sifive_gpio_irq_set_type(struct irq_data *d, unsigned int trigger)
+{
+	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+	struct sifive_gpio *chip = gpiochip_get_data(gc);
+	int offset = irqd_to_hwirq(d);
+
+	if (offset < 0 || offset >= gc->ngpio)
+		return -EINVAL;
+
+	chip->trigger[offset] = trigger;
+	sifive_gpio_set_ie(chip, offset);
+	return 0;
+}
+
+static void sifive_gpio_irq_enable(struct irq_data *d)
+{
+	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+	struct sifive_gpio *chip = gpiochip_get_data(gc);
+	int offset = irqd_to_hwirq(d) % SIFIVE_GPIO_MAX;
+	u32 bit = BIT(offset);
+	unsigned long flags;
+
+	irq_chip_enable_parent(d);
+
+	/* Switch to input */
+	gc->direction_input(gc, offset);
+
+	spin_lock_irqsave(&gc->bgpio_lock, flags);
+	/* Clear any sticky pending interrupts */
+	regmap_write(chip->regs, SIFIVE_GPIO_RISE_IP, bit);
+	regmap_write(chip->regs, SIFIVE_GPIO_FALL_IP, bit);
+	regmap_write(chip->regs, SIFIVE_GPIO_HIGH_IP, bit);
+	regmap_write(chip->regs, SIFIVE_GPIO_LOW_IP, bit);
+	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
+
+	/* Enable interrupts */
+	assign_bit(offset, (unsigned long *)&chip->irq_state, 1);
+	sifive_gpio_set_ie(chip, offset);
+}
+
+static void sifive_gpio_irq_disable(struct irq_data *d)
+{
+	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+	struct sifive_gpio *chip = gpiochip_get_data(gc);
+	int offset = irqd_to_hwirq(d) % SIFIVE_GPIO_MAX;
+
+	assign_bit(offset, (unsigned long *)&chip->irq_state, 0);
+	sifive_gpio_set_ie(chip, offset);
+	irq_chip_disable_parent(d);
+}
+
+static void sifive_gpio_irq_eoi(struct irq_data *d)
+{
+	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+	struct sifive_gpio *chip = gpiochip_get_data(gc);
+	int offset = irqd_to_hwirq(d) % SIFIVE_GPIO_MAX;
+	u32 bit = BIT(offset);
+	unsigned long flags;
+
+	spin_lock_irqsave(&gc->bgpio_lock, flags);
+	/* Clear all pending interrupts */
+	regmap_write(chip->regs, SIFIVE_GPIO_RISE_IP, bit);
+	regmap_write(chip->regs, SIFIVE_GPIO_FALL_IP, bit);
+	regmap_write(chip->regs, SIFIVE_GPIO_HIGH_IP, bit);
+	regmap_write(chip->regs, SIFIVE_GPIO_LOW_IP, bit);
+	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
+
+	irq_chip_eoi_parent(d);
+}
+
+static struct irq_chip sifive_gpio_irqchip = {
+	.name		= "sifive-gpio",
+	.irq_set_type	= sifive_gpio_irq_set_type,
+	.irq_mask	= irq_chip_mask_parent,
+	.irq_unmask	= irq_chip_unmask_parent,
+	.irq_enable	= sifive_gpio_irq_enable,
+	.irq_disable	= sifive_gpio_irq_disable,
+	.irq_eoi	= sifive_gpio_irq_eoi,
+};
+
+static int sifive_gpio_child_to_parent_hwirq(struct gpio_chip *gc,
+					     unsigned int child,
+					     unsigned int child_type,
+					     unsigned int *parent,
+					     unsigned int *parent_type)
+{
+	*parent_type = IRQ_TYPE_NONE;
+	*parent = child + SIFIVE_GPIO_IRQ_OFFSET;
+	return 0;
+}
+
+static const struct regmap_config sifive_gpio_regmap_config = {
+	.reg_bits = 32,
+	.reg_stride = 4,
+	.val_bits = 32,
+	.fast_io = true,
+	.disable_locking = true,
+};
+
+static int sifive_gpio_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *node = pdev->dev.of_node;
+	struct device_node *irq_parent;
+	struct irq_domain *parent;
+	struct gpio_irq_chip *girq;
+	struct sifive_gpio *chip;
+	int ret, ngpio;
+
+	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
+	if (!chip)
+		return -ENOMEM;
+
+	chip->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(chip->base)) {
+		dev_err(dev, "failed to allocate device memory\n");
+		return PTR_ERR(chip->base);
+	}
+
+	chip->regs = devm_regmap_init_mmio(dev, chip->base,
+					   &sifive_gpio_regmap_config);
+	if (IS_ERR(chip->regs))
+		return PTR_ERR(chip->regs);
+
+	ngpio = of_irq_count(node);
+	if (ngpio >= SIFIVE_GPIO_MAX) {
+		dev_err(dev, "Too many GPIO interrupts (max=%d)\n",
+			SIFIVE_GPIO_MAX);
+		return -ENXIO;
+	}
+
+	irq_parent = of_irq_find_parent(node);
+	if (!irq_parent) {
+		dev_err(dev, "no IRQ parent node\n");
+		return -ENODEV;
+	}
+	parent = irq_find_host(irq_parent);
+	if (!parent) {
+		dev_err(dev, "no IRQ parent domain\n");
+		return -ENODEV;
+	}
+
+	ret = bgpio_init(&chip->gc, dev, 4,
+			 chip->base + SIFIVE_GPIO_INPUT_VAL,
+			 chip->base + SIFIVE_GPIO_OUTPUT_VAL,
+			 NULL,
+			 chip->base + SIFIVE_GPIO_OUTPUT_EN,
+			 chip->base + SIFIVE_GPIO_INPUT_EN,
+			 0);
+	if (ret) {
+		dev_err(dev, "unable to init generic GPIO\n");
+		return ret;
+	}
+
+	/* Disable all GPIO interrupts before enabling parent interrupts */
+	regmap_write(chip->regs, SIFIVE_GPIO_RISE_IE, 0);
+	regmap_write(chip->regs, SIFIVE_GPIO_FALL_IE, 0);
+	regmap_write(chip->regs, SIFIVE_GPIO_HIGH_IE, 0);
+	regmap_write(chip->regs, SIFIVE_GPIO_LOW_IE, 0);
+	chip->irq_state = 0;
+
+	chip->gc.base = -1;
+	chip->gc.ngpio = ngpio;
+	chip->gc.label = dev_name(dev);
+	chip->gc.parent = dev;
+	chip->gc.owner = THIS_MODULE;
+	girq = &chip->gc.irq;
+	girq->chip = &sifive_gpio_irqchip;
+	girq->fwnode = of_node_to_fwnode(node);
+	girq->parent_domain = parent;
+	girq->child_to_parent_hwirq = sifive_gpio_child_to_parent_hwirq;
+	girq->handler = handle_bad_irq;
+	girq->default_type = IRQ_TYPE_NONE;
+
+	platform_set_drvdata(pdev, chip);
+	return gpiochip_add_data(&chip->gc, chip);
+}
+
+static const struct of_device_id sifive_gpio_match[] = {
+	{ .compatible = "sifive,gpio0" },
+	{ .compatible = "sifive,fu540-c000-gpio" },
+	{ },
+};
+
+static struct platform_driver sifive_gpio_driver = {
+	.probe		= sifive_gpio_probe,
+	.driver = {
+		.name	= "sifive_gpio",
+		.of_match_table = of_match_ptr(sifive_gpio_match),
+	},
+};
+builtin_platform_driver(sifive_gpio_driver)