[U-Boot] [PATCH v5 081/101] x86: Add a generic Intel GPIO driver

Bin Meng bmeng.cn at gmail.com
Mon Dec 2 04:40:12 CET 2019


Hi Simon,

On Mon, Nov 25, 2019 at 12:12 PM Simon Glass <sjg at chromium.org> wrote:
>
> Add a GPIO driver which uses the pinctrl driver to access the pad
> information. This driver relies on the GPIO nodes being subnodes to the
> pinctrl device.
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
>
> Changes in v5: None
> Changes in v4: None
> Changes in v3: None
> Changes in v2: None
>
>  .../gpio/intel,apl-gpio.txt                   |  55 ++++++
>  drivers/gpio/Kconfig                          |   9 +
>  drivers/gpio/Makefile                         |   1 +
>  drivers/gpio/intel_gpio.c                     | 161 ++++++++++++++++++
>  4 files changed, 226 insertions(+)
>  create mode 100644 doc/device-tree-bindings/gpio/intel,apl-gpio.txt
>  create mode 100644 drivers/gpio/intel_gpio.c
>
> diff --git a/doc/device-tree-bindings/gpio/intel,apl-gpio.txt b/doc/device-tree-bindings/gpio/intel,apl-gpio.txt
> new file mode 100644
> index 0000000000..e34e7c3501
> --- /dev/null
> +++ b/doc/device-tree-bindings/gpio/intel,apl-gpio.txt
> @@ -0,0 +1,55 @@
> +* Intel Apollo Lake GPIO controller

nits: remove the *

> +
> +The Apollo Lake (APL) GPIO controller is used to control GPIO functions of
> +the pins.
> +
> +Required properties:
> +- compatible: "intel,apl-gpio"
> +- #gpio-cells: Should be 2. The syntax of the gpio specifier used by client
> +  nodes should be the following with values derived from the SoC user manual.
> +     <[phandle of the gpio controller node]
> +      [pin number within the gpio controller]
> +      [flags]>
> +
> +  Values for gpio specifier:
> +  - Pin number: is a GPIO pin number between 0 and 244
> +  - Flags: GPIO_ACTIVE_HIGH or GPIO_ACTIVE_LOW
> +
> +- gpio-controller: Specifies that the node is a gpio controller.
> +
> +Example:
> +
> +...
> +{
> +       p2sb: p2sb at d,0 {
> +               reg = <0x02006810 0 0 0 0>;
> +               compatible = "intel,apl-p2sb";
> +               early-regs = <IOMAP_P2SB_BAR 0x100000>;
> +
> +               n {

Need a more descriptive name

> +                       compatible = "intel,apl-pinctrl";
> +                       intel,p2sb-port-id = <PID_GPIO_N>;
> +                       gpio_n: gpio-n {
> +                               compatible = "intel,apl-gpio";
> +                               gpio-controller;
> +                               #gpio-cells = <2>;
> +                       };
> +               };
> +       };
> +
> +       i2c_2: i2c2 at 16,2 {
> +               compatible = "intel,apl-i2c", "snps,designware-i2c-pci";
> +               reg = <0x0200b210 0 0 0 0>;
> +               #address-cells = <1>;
> +               #size-cells = <0>;
> +               clock-frequency = <400000>;
> +               tpm at 50 {
> +                       reg = <0x50>;
> +                       compatible = "google,cr50";
> +                       u-boot,i2c-offset-len = <0>;
> +                       ready-gpio = <&gpio_n GPIO_28 GPIO_ACTIVE_LOW>;
> +               };
> +       };
> +
> +};
> +...
> diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
> index 447cf04578..1de6f5225e 100644
> --- a/drivers/gpio/Kconfig
> +++ b/drivers/gpio/Kconfig
> @@ -104,6 +104,15 @@ config INTEL_BROADWELL_GPIO
>           driver from the common Intel ICH6 driver. It supports a total of
>           95 GPIOs which can be configured from the device tree.
>
> +config INTEL_GPIO
> +       bool "Intel generic GPIO driver"
> +       depends on DM_GPIO
> +       help
> +         Say yes here to select Intel generic GPIO driver. This controller
> +         supports recent chips (e.g. Apollo Lake). It permits basic GPIO
> +         control including setting pins to input/output. It makes use of its
> +         parent pinctrl driver to actually effect changes.
> +
>  config INTEL_ICH6_GPIO
>         bool "Intel ICH6 compatible legacy GPIO driver"
>         depends on DM_GPIO
> diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
> index 3612e66786..449046b64c 100644
> --- a/drivers/gpio/Makefile
> +++ b/drivers/gpio/Makefile
> @@ -17,6 +17,7 @@ endif
>  obj-$(CONFIG_AT91_GPIO)        += at91_gpio.o
>  obj-$(CONFIG_ATMEL_PIO4)       += atmel_pio4.o
>  obj-$(CONFIG_BCM6345_GPIO)     += bcm6345_gpio.o
> +obj-$(CONFIG_INTEL_GPIO)       += intel_gpio.o
>  obj-$(CONFIG_INTEL_ICH6_GPIO)  += intel_ich6_gpio.o
>  obj-$(CONFIG_INTEL_BROADWELL_GPIO)     += intel_broadwell_gpio.o
>  obj-$(CONFIG_KIRKWOOD_GPIO)    += kw_gpio.o
> diff --git a/drivers/gpio/intel_gpio.c b/drivers/gpio/intel_gpio.c
> new file mode 100644
> index 0000000000..eeff95de7b
> --- /dev/null
> +++ b/drivers/gpio/intel_gpio.c
> @@ -0,0 +1,161 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright 2019 Google LLC
> + */
> +
> +#include <common.h>
> +#include <dm.h>
> +#include <errno.h>
> +#include <fdtdec.h>
> +#include <p2sb.h>
> +#include <pch.h>
> +#include <pci.h>
> +#include <syscon.h>
> +#include <asm/cpu.h>
> +#include <asm/gpio.h>
> +#include <asm/intel_pinctrl.h>
> +#include <asm/intel_pinctrl_defs.h>
> +#include <asm/io.h>
> +#include <asm/pci.h>
> +#include <asm/arch/gpio.h>
> +#include <dt-bindings/gpio/x86-gpio.h>
> +
> +static int intel_gpio_direction_input(struct udevice *dev, uint offset)
> +{
> +       struct udevice *pinctrl = dev_get_parent(dev);
> +       uint config_offset = intel_pinctrl_get_config_reg_addr(pinctrl, offset);
> +
> +       pcr_clrsetbits32(pinctrl, config_offset,
> +                        PAD_CFG0_MODE_MASK | PAD_CFG0_TX_STATE |
> +                                 PAD_CFG0_RX_DISABLE,
> +                        PAD_CFG0_MODE_GPIO | PAD_CFG0_TX_DISABLE);
> +
> +       return 0;
> +}
> +
> +static int intel_gpio_direction_output(struct udevice *dev, uint offset,
> +                                      int value)
> +{
> +       struct udevice *pinctrl = dev_get_parent(dev);
> +       uint config_offset = intel_pinctrl_get_config_reg_addr(pinctrl, offset);
> +
> +       pcr_clrsetbits32(dev, config_offset,
> +                        PAD_CFG0_MODE_MASK | PAD_CFG0_RX_STATE |
> +                                 PAD_CFG0_TX_DISABLE,
> +                        PAD_CFG0_MODE_GPIO | PAD_CFG0_RX_DISABLE |
> +                                 (value ? PAD_CFG0_TX_STATE : 0));
> +
> +       return 0;
> +}
> +
> +static int intel_gpio_get_value(struct udevice *dev, uint offset)
> +{
> +       struct udevice *pinctrl = dev_get_parent(dev);
> +       uint mode, rx_tx;
> +       u32 reg;
> +
> +       reg = intel_pinctrl_get_config_reg(pinctrl, offset);
> +       mode = (reg & PAD_CFG0_MODE_MASK) >> PAD_CFG0_MODE_SHIFT;
> +       if (!mode) {
> +               rx_tx = reg & (PAD_CFG0_TX_DISABLE | PAD_CFG0_RX_DISABLE);
> +               if (rx_tx == PAD_CFG0_TX_DISABLE)
> +                       return mode & PAD_CFG0_RX_STATE_BIT ? 1 : 0;
> +               else if (rx_tx == PAD_CFG0_RX_DISABLE)
> +                       return mode & PAD_CFG0_TX_STATE_BIT ? 1 : 0;
> +       }
> +
> +       return 0;
> +}
> +
> +static int intel_gpio_set_value(struct udevice *dev, unsigned offset, int value)
> +{
> +       struct udevice *pinctrl = dev_get_parent(dev);
> +       uint config_offset = intel_pinctrl_get_config_reg_addr(pinctrl, offset);
> +
> +       pcr_clrsetbits32(dev, config_offset, PAD_CFG0_TX_STATE,
> +                        value ? PAD_CFG0_TX_STATE : 0);
> +
> +       return 0;
> +}
> +
> +static int intel_gpio_get_function(struct udevice *dev, uint offset)
> +{
> +       struct udevice *pinctrl = dev_get_parent(dev);
> +       uint mode, rx_tx;
> +       u32 reg;
> +
> +       reg = intel_pinctrl_get_config_reg(pinctrl, offset);
> +       mode = (reg & PAD_CFG0_MODE_MASK) >> PAD_CFG0_MODE_SHIFT;
> +       if (!mode) {
> +               rx_tx = reg & (PAD_CFG0_TX_DISABLE | PAD_CFG0_RX_DISABLE);
> +               if (rx_tx == PAD_CFG0_TX_DISABLE)
> +                       return GPIOF_INPUT;
> +               else if (rx_tx == PAD_CFG0_RX_DISABLE)
> +                       return GPIOF_OUTPUT;
> +       }
> +
> +       return GPIOF_FUNC;
> +}
> +
> +static int intel_gpio_xlate(struct udevice *orig_dev, struct gpio_desc *desc,
> +                           struct ofnode_phandle_args *args)
> +{
> +       struct udevice *pinctrl, *dev;
> +       int gpio, ret;
> +
> +       /*
> +        * GPIO numbers are global in the device tree so it doesn't matter
> +        * which hone is used

What is hone?

> +        */
> +       gpio = args->args[0];
> +       ret = intel_pinctrl_get_pad(gpio, &pinctrl, &desc->offset);
> +       if (ret)
> +               return log_msg_ret("bad", ret);
> +       device_find_first_child(pinctrl, &dev);
> +       if (!dev)
> +               return log_msg_ret("no child", -ENOENT);
> +       desc->flags = args->args[1] & GPIO_ACTIVE_LOW ? GPIOD_ACTIVE_LOW : 0;
> +       desc->dev = dev;
> +
> +       return 0;
> +}
> +
> +static int intel_gpio_probe(struct udevice *dev)
> +{
> +       return 0;
> +}
> +
> +static int intel_gpio_ofdata_to_platdata(struct udevice *dev)
> +{
> +       struct gpio_dev_priv *upriv = dev_get_uclass_priv(dev);
> +       struct intel_pinctrl_priv *pinctrl_priv = dev_get_priv(dev->parent);
> +       const struct pad_community *comm = pinctrl_priv->comm;
> +
> +       upriv->gpio_count = comm->last_pad - comm->first_pad + 1;
> +       upriv->bank_name = dev->name;
> +
> +       return 0;
> +}
> +
> +static const struct dm_gpio_ops gpio_intel_ops = {
> +       .direction_input        = intel_gpio_direction_input,
> +       .direction_output       = intel_gpio_direction_output,
> +       .get_value              = intel_gpio_get_value,
> +       .set_value              = intel_gpio_set_value,
> +       .get_function           = intel_gpio_get_function,
> +       .xlate                  = intel_gpio_xlate,
> +};
> +
> +static const struct udevice_id intel_intel_gpio_ids[] = {
> +       { .compatible = "intel,apl-gpio" },

If this is a generic Intel GPIO driver, probably we need a generic
compatible string like "intel,gpio", and make use of the driver data
for different SoC variants.

> +       { }
> +};
> +
> +U_BOOT_DRIVER(gpio_intel) = {
> +       .name   = "gpio_intel",
> +       .id     = UCLASS_GPIO,
> +       .of_match = intel_intel_gpio_ids,
> +       .ops    = &gpio_intel_ops,
> +       .ofdata_to_platdata     = intel_gpio_ofdata_to_platdata,
> +       .probe  = intel_gpio_probe,
> +};
> --

Regards,
Bin


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