diff options
| -rw-r--r-- | arch/arm/include/asm/arch-zynq/gpio.h | 66 | ||||
| -rw-r--r-- | drivers/gpio/Makefile | 1 | ||||
| -rw-r--r-- | drivers/gpio/zynq_gpio.c | 220 |
3 files changed, 287 insertions, 0 deletions
diff --git a/arch/arm/include/asm/arch-zynq/gpio.h b/arch/arm/include/asm/arch-zynq/gpio.h index a26ae87..9e1e7da 100644 --- a/arch/arm/include/asm/arch-zynq/gpio.h +++ b/arch/arm/include/asm/arch-zynq/gpio.h @@ -1,5 +1,6 @@ /* * Copyright (c) 2013 Xilinx, Inc. + * Copyright (c) 2015 DAVE Embedded Systems * * SPDX-License-Identifier: GPL-2.0+ */ @@ -7,4 +8,69 @@ #ifndef _ZYNQ_GPIO_H #define _ZYNQ_GPIO_H +#define ZYNQ_GPIO_BASE_ADDRESS 0xE000A000 + +/* Maximum banks */ +#define ZYNQ_GPIO_MAX_BANK 4 + +#define ZYNQ_GPIO_BANK0_NGPIO 32 +#define ZYNQ_GPIO_BANK1_NGPIO 22 +#define ZYNQ_GPIO_BANK2_NGPIO 32 +#define ZYNQ_GPIO_BANK3_NGPIO 32 + +#define ZYNQ_GPIO_NR_GPIOS (ZYNQ_GPIO_BANK0_NGPIO + \ + ZYNQ_GPIO_BANK1_NGPIO + \ + ZYNQ_GPIO_BANK2_NGPIO + \ + ZYNQ_GPIO_BANK3_NGPIO) + +#define ZYNQ_GPIO_BANK0_PIN_MIN 0 +#define ZYNQ_GPIO_BANK0_PIN_MAX (ZYNQ_GPIO_BANK0_PIN_MIN + \ + ZYNQ_GPIO_BANK0_NGPIO - 1) +#define ZYNQ_GPIO_BANK1_PIN_MIN (ZYNQ_GPIO_BANK0_PIN_MAX + 1) +#define ZYNQ_GPIO_BANK1_PIN_MAX (ZYNQ_GPIO_BANK1_PIN_MIN + \ + ZYNQ_GPIO_BANK1_NGPIO - 1) +#define ZYNQ_GPIO_BANK2_PIN_MIN (ZYNQ_GPIO_BANK1_PIN_MAX + 1) +#define ZYNQ_GPIO_BANK2_PIN_MAX (ZYNQ_GPIO_BANK2_PIN_MIN + \ + ZYNQ_GPIO_BANK2_NGPIO - 1) +#define ZYNQ_GPIO_BANK3_PIN_MIN (ZYNQ_GPIO_BANK2_PIN_MAX + 1) +#define ZYNQ_GPIO_BANK3_PIN_MAX (ZYNQ_GPIO_BANK3_PIN_MIN + \ + ZYNQ_GPIO_BANK3_NGPIO - 1) + +/* Register offsets for the GPIO device */ +/* LSW Mask & Data -WO */ +#define ZYNQ_GPIO_DATA_LSW_OFFSET(BANK) (0x000 + (8 * BANK)) +/* MSW Mask & Data -WO */ +#define ZYNQ_GPIO_DATA_MSW_OFFSET(BANK) (0x004 + (8 * BANK)) +/* Data Register-RW */ +#define ZYNQ_GPIO_DATA_RO_OFFSET(BANK) (0x060 + (4 * BANK)) +/* Direction mode reg-RW */ +#define ZYNQ_GPIO_DIRM_OFFSET(BANK) (0x204 + (0x40 * BANK)) +/* Output enable reg-RW */ +#define ZYNQ_GPIO_OUTEN_OFFSET(BANK) (0x208 + (0x40 * BANK)) +/* Interrupt mask reg-RO */ +#define ZYNQ_GPIO_INTMASK_OFFSET(BANK) (0x20C + (0x40 * BANK)) +/* Interrupt enable reg-WO */ +#define ZYNQ_GPIO_INTEN_OFFSET(BANK) (0x210 + (0x40 * BANK)) +/* Interrupt disable reg-WO */ +#define ZYNQ_GPIO_INTDIS_OFFSET(BANK) (0x214 + (0x40 * BANK)) +/* Interrupt status reg-RO */ +#define ZYNQ_GPIO_INTSTS_OFFSET(BANK) (0x218 + (0x40 * BANK)) +/* Interrupt type reg-RW */ +#define ZYNQ_GPIO_INTTYPE_OFFSET(BANK) (0x21C + (0x40 * BANK)) +/* Interrupt polarity reg-RW */ +#define ZYNQ_GPIO_INTPOL_OFFSET(BANK) (0x220 + (0x40 * BANK)) +/* Interrupt on any, reg-RW */ +#define ZYNQ_GPIO_INTANY_OFFSET(BANK) (0x224 + (0x40 * BANK)) + +/* Disable all interrupts mask */ +#define ZYNQ_GPIO_IXR_DISABLE_ALL 0xFFFFFFFF + +/* Mid pin number of a bank */ +#define ZYNQ_GPIO_MID_PIN_NUM 16 + +/* GPIO upper 16 bit mask */ +#define ZYNQ_GPIO_UPPER_MASK 0xFFFF0000 + +#define BIT(x) (1<<x) + #endif /* _ZYNQ_GPIO_H */ diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile index 8ca8b05..fb40e09 100644 --- a/drivers/gpio/Makefile +++ b/drivers/gpio/Makefile @@ -43,3 +43,4 @@ oby-$(CONFIG_SX151X) += sx151x.o obj-$(CONFIG_SUNXI_GPIO) += sunxi_gpio.o obj-$(CONFIG_LPC32XX_GPIO) += lpc32xx_gpio.o obj-$(CONFIG_STM32_GPIO) += stm32_gpio.o +obj-$(CONFIG_ZYNQ_GPIO) += zynq_gpio.o diff --git a/drivers/gpio/zynq_gpio.c b/drivers/gpio/zynq_gpio.c new file mode 100644 index 0000000..83a2c46 --- /dev/null +++ b/drivers/gpio/zynq_gpio.c @@ -0,0 +1,220 @@ +/* + * Xilinx Zynq GPIO device driver + * + * Copyright (C) 2015 DAVE Embedded Systems <devel@dave.eu> + * + * Most of code taken from linux kernel driver (linux/drivers/gpio/gpio-zynq.c) + * Copyright (C) 2009 - 2014 Xilinx, Inc. + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <asm/gpio.h> +#include <asm/io.h> +#include <asm/errno.h> + +/** + * zynq_gpio_get_bank_pin - Get the bank number and pin number within that bank + * for a given pin in the GPIO device + * @pin_num: gpio pin number within the device + * @bank_num: an output parameter used to return the bank number of the gpio + * pin + * @bank_pin_num: an output parameter used to return pin number within a bank + * for the given gpio pin + * + * Returns the bank number and pin offset within the bank. + */ +static inline void zynq_gpio_get_bank_pin(unsigned int pin_num, + unsigned int *bank_num, + unsigned int *bank_pin_num) +{ + switch (pin_num) { + case ZYNQ_GPIO_BANK0_PIN_MIN ... ZYNQ_GPIO_BANK0_PIN_MAX: + *bank_num = 0; + *bank_pin_num = pin_num; + break; + case ZYNQ_GPIO_BANK1_PIN_MIN ... ZYNQ_GPIO_BANK1_PIN_MAX: + *bank_num = 1; + *bank_pin_num = pin_num - ZYNQ_GPIO_BANK1_PIN_MIN; + break; + case ZYNQ_GPIO_BANK2_PIN_MIN ... ZYNQ_GPIO_BANK2_PIN_MAX: + *bank_num = 2; + *bank_pin_num = pin_num - ZYNQ_GPIO_BANK2_PIN_MIN; + break; + case ZYNQ_GPIO_BANK3_PIN_MIN ... ZYNQ_GPIO_BANK3_PIN_MAX: + *bank_num = 3; + *bank_pin_num = pin_num - ZYNQ_GPIO_BANK3_PIN_MIN; + break; + default: + printf("invalid GPIO pin number: %u\n", pin_num); + *bank_num = 0; + *bank_pin_num = 0; + break; + } +} + +int gpio_is_valid(unsigned gpio) +{ + return (gpio >= 0) && (gpio < ZYNQ_GPIO_NR_GPIOS); +} + +static int check_gpio(unsigned gpio) +{ + if (!gpio_is_valid(gpio)) { + printf("ERROR : check_gpio: invalid GPIO %d\n", gpio); + return -1; + } + return 0; +} + +/** + * gpio_get_value - Get the state of the specified pin of GPIO device + * @gpio: gpio pin number within the device + * + * This function reads the state of the specified pin of the GPIO device. + * + * Return: 0 if the pin is low, 1 if pin is high. + */ +int gpio_get_value(unsigned gpio) +{ + u32 data; + unsigned int bank_num, bank_pin_num; + + if (check_gpio(gpio) < 0) + return -1; + + zynq_gpio_get_bank_pin(gpio, &bank_num, &bank_pin_num); + + data = readl(ZYNQ_GPIO_BASE_ADDRESS + + ZYNQ_GPIO_DATA_RO_OFFSET(bank_num)); + + return (data >> bank_pin_num) & 1; +} + +/** + * gpio_set_value - Modify the value of the pin with specified value + * @gpio: gpio pin number within the device + * @value: value used to modify the value of the specified pin + * + * This function calculates the register offset (i.e to lower 16 bits or + * upper 16 bits) based on the given pin number and sets the value of a + * gpio pin to the specified value. The value is either 0 or non-zero. + */ +int gpio_set_value(unsigned gpio, int value) +{ + unsigned int reg_offset, bank_num, bank_pin_num; + + if (check_gpio(gpio) < 0) + return -1; + + zynq_gpio_get_bank_pin(gpio, &bank_num, &bank_pin_num); + + if (bank_pin_num >= ZYNQ_GPIO_MID_PIN_NUM) { + /* only 16 data bits in bit maskable reg */ + bank_pin_num -= ZYNQ_GPIO_MID_PIN_NUM; + reg_offset = ZYNQ_GPIO_DATA_MSW_OFFSET(bank_num); + } else { + reg_offset = ZYNQ_GPIO_DATA_LSW_OFFSET(bank_num); + } + + /* + * get the 32 bit value to be written to the mask/data register where + * the upper 16 bits is the mask and lower 16 bits is the data + */ + value = !!value; + value = ~(1 << (bank_pin_num + ZYNQ_GPIO_MID_PIN_NUM)) & + ((value << bank_pin_num) | ZYNQ_GPIO_UPPER_MASK); + + writel(value, ZYNQ_GPIO_BASE_ADDRESS + reg_offset); + + return 0; +} + +/** + * gpio_direction_input - Set the direction of the specified GPIO pin as input + * @gpio: gpio pin number within the device + * + * This function uses the read-modify-write sequence to set the direction of + * the gpio pin as input. + * + * Return: -1 if invalid gpio specified, 0 if successul + */ +int gpio_direction_input(unsigned gpio) +{ + u32 reg; + unsigned int bank_num, bank_pin_num; + + if (check_gpio(gpio) < 0) + return -1; + + zynq_gpio_get_bank_pin(gpio, &bank_num, &bank_pin_num); + + /* bank 0 pins 7 and 8 are special and cannot be used as inputs */ + if (bank_num == 0 && (bank_pin_num == 7 || bank_pin_num == 8)) + return -1; + + /* clear the bit in direction mode reg to set the pin as input */ + reg = readl(ZYNQ_GPIO_BASE_ADDRESS + ZYNQ_GPIO_DIRM_OFFSET(bank_num)); + reg &= ~BIT(bank_pin_num); + writel(reg, ZYNQ_GPIO_BASE_ADDRESS + ZYNQ_GPIO_DIRM_OFFSET(bank_num)); + + return 0; +} + +/** + * gpio_direction_output - Set the direction of the specified GPIO pin as output + * @gpio: gpio pin number within the device + * @value: value to be written to specified pin + * + * This function sets the direction of specified GPIO pin as output, configures + * the Output Enable register for the pin and uses zynq_gpio_set to set + * the value of the pin to the value specified. + * + * Return: 0 always + */ +int gpio_direction_output(unsigned gpio, int value) +{ + u32 reg; + unsigned int bank_num, bank_pin_num; + + if (check_gpio(gpio) < 0) + return -1; + + zynq_gpio_get_bank_pin(gpio, &bank_num, &bank_pin_num); + + /* set the GPIO pin as output */ + reg = readl(ZYNQ_GPIO_BASE_ADDRESS + ZYNQ_GPIO_DIRM_OFFSET(bank_num)); + reg |= BIT(bank_pin_num); + writel(reg, ZYNQ_GPIO_BASE_ADDRESS + ZYNQ_GPIO_DIRM_OFFSET(bank_num)); + + /* configure the output enable reg for the pin */ + reg = readl(ZYNQ_GPIO_BASE_ADDRESS + ZYNQ_GPIO_OUTEN_OFFSET(bank_num)); + reg |= BIT(bank_pin_num); + writel(reg, ZYNQ_GPIO_BASE_ADDRESS + ZYNQ_GPIO_OUTEN_OFFSET(bank_num)); + + /* set the state of the pin */ + gpio_set_value(gpio, value); + return 0; +} + +/** + * Request a gpio before using it. + * + * NOTE: Argument 'label' is unused. + */ +int gpio_request(unsigned gpio, const char *label) +{ + if (check_gpio(gpio) < 0) + return -1; + + return 0; +} + +/** + * Reset and free the gpio after using it. + */ +int gpio_free(unsigned gpio) +{ + return 0; +} |