mirror of
https://github.com/saymrwulf/pulp-runtime.git
synced 2026-05-16 21:00:16 +00:00
Add first driver draft for new gpio peripheral
This commit is contained in:
Manuel Eggimann
parent
d69fbeff36
commit
d8dc704518
6 changed files with 485 additions and 3 deletions
41
drivers/gpio/gpio.c
Normal file
41
drivers/gpio/gpio.c
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@ -0,0 +1,41 @@
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#include "gpio.h"
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#include "common/bitfield.h"
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#include "gpio_hal.h"
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#include "pulp.h"
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void gpio_configure(uint32_t number, uint32_t direction){
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// Now configure the GPIO peripheral
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uint32_t addr = ARCHI_GPIO_ADDR + GPIO_MODE_REG_OFFSET_BASE + number/16*4;
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uint32_t reg = archi_read32(addr);
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bitfield_field32_t field;
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field.mask = 0x3;
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field.index = number%16*2;
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reg = bitfield_field32_write(reg, field, (direction == GPIO_DIRECTION_INPUT)? GPIO_MODE_REG_VALUE_INPUT_ONLY: GPIO_MODE_REG_VALUE_OUTPUT_ACTIVE);
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archi_write32(addr, reg);
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// Enable/Disable input sampling
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addr = ARCHI_GPIO_ADDR + GPIO_EN_INPUT_REG_OFFSET_BASE + number/32*4;
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reg = archi_read32(addr);
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reg = bitfield_bit32_write(reg, number%32, direction == SIRACUSA_GPIO_DIRECTION_INPUT);
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archi_write32(addr, reg);
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hal_compiler_barrier();
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}
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void gpio_set(uint32_t number, uint32_t value){
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uint32_t addr;
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if (value == 1) {
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addr = ARCHI_GPIO_ADDR + GPIO_SET_REG_OFFSET_BASE + number/32*4;
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} else {
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addr = SIRACUSA_GPIO_BASE_ADDR + GPIO_CLEAR_REG_OFFSET_BASE + number/32*4;
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}
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archi_write32(addr, 1<<(number%32));
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hal_compiler_barrier();
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}
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uint32_t gpio_get(uint32_t number){
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uint32_t addr = SIRACUSA_GPIO_BASE_ADDR + GPIO_GPIO_IN_0_REG_OFFSET + number/32*4;
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uint32_t reg = archi_read32(addr);
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return bitfield_bit32_read(reg, number%32);
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hal_compiler_barrier();
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}
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64
drivers/gpio/include/gpio.h
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64
drivers/gpio/include/gpio.h
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@ -0,0 +1,64 @@
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/*
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* Copyright (C) 2022 ETH Zurich, University of Bologna
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*
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* Title: gpio.h<include>
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* Author: Manuel Eggimann <meggimann@iis.ee.ethz.ch>
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* Date: 09.03.2022
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*
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* Description: Driver for the PULP GPIO peripheral
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*/
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#ifndef GPIO_H
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#define GPIO_H
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#include <stdint.h>
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#define GPIO_DIRECTION_OUTPUT 1
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#define GPIO_DIRECTION_INPUT 0
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/**
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* Configure the provided GPIO as either an input or output.
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*
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* It is the user's responsibility to ensure that the GPIO to be configures is
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* actually exposed to its corresponding IO pad. I.e. if your SoC contains an IO
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* multiplexer you have to make sure you configure it apropriately to expose the
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* GPIO on the pad.
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*
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* @param number The GPIO number to confgiure. You can either use directly an integer number or on of the PAD_GPIOXX macros.
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* @param direction Either GPIO_DIRECTION_INPUT (0) or GPIO_DIRECTION_OUTPUT
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*/
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void gpio_configure(uint32_t number, uint32_t direction);
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/**
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* Get the current value of the GPIO.
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*
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* The GPIO must have been configured as an input using configure_gpio().
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*
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* @param number The GPIO number to confgiure. You can either use directly an integer number or on of the PAD_GPIOXX macros.
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* @returns 0 if the gpio is currently at logic level LOW or 1 if it is at logic level HIGH.
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*/
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uint32_t gpio_get(uint32_t number);
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/**
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* Drive the GPIO to the provided value.
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*
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* The corresponding GPIO must have been configured as an output using configure_gpio().
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*
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* @param number The GPIO number to confgiure. You can either use directly an integer number or on of the PAD_GPIOXX macros.
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* @param value Either 0 or 1.
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*/
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void gpio_set(uint32_t number, uint32_t value);
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#endif /* GPIO_H */
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86
drivers/gpio/include/gpio_hal.h
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86
drivers/gpio/include/gpio_hal.h
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// Generic Hardware Abstraction Layer for the GPIO peripheral
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#ifndef _GPIO_REG_DEFS_
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#define _GPIO_REG_DEFS_
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#ifdef __cplusplus
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extern "C" {
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#endif
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// Info register that contains information about this peripheral.
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#define GPIO_INFO_REG_OFFSET 0x0
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#define GPIO_INFO_REG_GPIO_CNT_MASK 0x3ff
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#define GPIO_INFO_REG_GPIO_CNT_OFFSET 0
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#define GPIO_INFO_REG_GPIO_CNT_FIELD \
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((bitfield_field32_t) { .mask = GPIO_INFO_GPIO_CNT_MASK, .index = GPIO_INFO_GPIO_CNT_OFFSET })
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#define GPIO_INFO_REG_VERSION_MASK 0x3ff
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#define GPIO_INFO_REG_VERSION_OFFSET 10
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#define GPIO_INFO_REG_VERSION_FIELD \
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((bitfield_field32_t) { .mask = GPIO_INFO_VERSION_MASK, .index = GPIO_INFO_VERSION_OFFSET })
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// Global configuration register for the peripheral
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#define GPIO_CFG_REG_OFFSET 0x4
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#define GPIO_CFG_INTRPT_MODE_BIT 0
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// Set the IO Mode of the GPIO. (common parameters)
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#define GPIO_MODE_REG_OFFSET_BASE 0x8
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#define GPIO_MODE_REG_VALUE_INPUT_ONLY 0x0
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#define GPIO_MODE_REG_VALUE_OUTPUT_ACTIVE 0x1
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#define GPIO_MODE_REG_VALUE_OPEN_DRAIN0 0x2
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#define GPIO_MODE_REG_VALUE_OPEN_DRAIN1 0x3
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// Enable sampling on the corresponding GPIO (common parameters)
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#define GPIO_EN_INPUT_REG_OFFSET_BASE 0x80
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// Read the current input values of all GPIOs.
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#define GPIO_INPUT_REG_OFFSET_BASE 0x100
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// Set the output value of the corresponding GPIOs.
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#define GPIO_OUTPUT_REG_OFFSET_BASE 0x180
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// For each asserted bit in this register, set the corresponding bit in the
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// padout register.
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#define GPIO_SET_REG_OFFSET_BASE 0x200
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// For each asserted bit in this register, clear the corresponding bit in the
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// padout register.
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#define GPIO_CLEAR_REG_OFFSET_BASE 0X280
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// For each asserted bit in this register, toggle the corresponding bit in
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// the padout register.
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#define GPIO_TOGGLE_REG_OFFSET_BASE 0X300
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// Enable Interrupts on rising edges for the corresponding GPIO
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#define GPIO_INTRPT_RISE_EN_REG_OFFSET_BASE 0x380
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// Enable Interrupts on falling edges for the corresponding GPIO
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#define GPIO_INTRPT_FALL_EN_REG_OFFSET_BASE 0x400
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// Enable logic high level-sensitive Interrupts on the corresponding GPIO
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#define GPIO_INTRPT_HIGH_EN_REG_OFFSET_BASE 0x480
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// Enable logic low level-sensitive Interrupts on the corresponding GPIO
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#define GPIO_INTRPT_LOW_EN_REG_OFFSET_BASE 0x500
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// Asserted if there is any pending interrupts on corresponding GPIOs.
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#define GPIO_INTRPT_STATUS_REG_OFFSET_BASE 0x580
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// Asserted if there is a pending rise interrupts on corresponding GPIOs.
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#define GPIO_INTRPT_RISE_STATUS_REG_OFFSET_BASE 0x600
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// Asserted if there is any pending fall interrupts on corresponding GPIOs.
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#define GPIO_INTRPT_FALL_STATUS_REG_OFFSET_BASE 0x680
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// Asserted if there is any pending high-level interrupts on corresponding
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// GPIOs.
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#define GPIO_INTRPT_LVL_HIGH_STATUS_REG_OFFSET_BASE 0x700
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// Asserted if there is any pending low-level interrupts on corresponding
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// GPIOs.
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#define GPIO_INTRPT_LVL_LOW_STATUS_REG_OFFSET_BASE 0x780
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#ifdef __cplusplus
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} // extern "C"
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#endif
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#endif // _GPIO_REG_DEFS_
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// End generated register defines for gpio
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@ -26,9 +26,8 @@
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#define ARCHI_SOC_PERIPHERALS_ADDR 0x1A100000
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#define ARCHI_FC_TIMER_SIZE 0x00000800
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#define ARCHI_FC_TIMER_SIZE 0x00000800
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#define ARCHI_FLL_OFFSET 0x00000000
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#define ARCHI_GPIO_OFFSET 0x00001000
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#define ARCHI_UDMA_OFFSET 0x00002000
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#define ARCHI_APB_SOC_CTRL_OFFSET 0x00004000
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@ -37,7 +36,9 @@
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#define ARCHI_FC_TIMER_OFFSET 0x0000B000
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#define ARCHI_FC_HWPE_OFFSET 0x0000C000
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#define ARCHI_STDOUT_OFFSET 0x0000F000
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// Chip control port
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#define ARCHI_FLL_OFFSET 0x00020000
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#define ARCHI_PAD_CFG_OFFSET 0x00021000
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#define ARCHI_GPIO_ADDR ( ARCHI_SOC_PERIPHERALS_ADDR + ARCHI_GPIO_OFFSET )
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@ -243,4 +243,9 @@
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#define ARCHI_FC_EVT_QUEUE_ERROR 29
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/*
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* GPIO Count
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*/
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#define GPIOCount 32
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#endif
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285
include/common/bitfield.h
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285
include/common/bitfield.h
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// Copyright lowRISC contributors.
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// Licensed under the Apache License, Version 2.0, see LICENSE for details.
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// SPDX-License-Identifier: Apache-2.0
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#ifndef OPENTITAN_SW_DEVICE_LIB_BASE_BITFIELD_H_
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#define OPENTITAN_SW_DEVICE_LIB_BASE_BITFIELD_H_
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#include <stdbool.h>
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#include <stdint.h>
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#ifdef __cplusplus
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extern "C" {
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#endif // __cplusplus
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/**
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* @file
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* @brief Bitfield Manipulation Functions
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*/
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/**
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* All the bitfield functions are pure (they do not modify their arguments), so
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* the result must be used. We enable warnings to ensure this happens.
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*/
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#define BITFIELD_WARN_UNUSED_RESULT __attribute__((warn_unused_result))
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/**
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* A field of a 32-bit bitfield.
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*
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* The following field definition: `{ .mask = 0b11, .index = 12 }`
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*
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* Denotes the X-marked bits in the following 32-bit bitfield:
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*
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* field: 0b--------'--------'--XX----'--------
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* index: 31 0
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*
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* Restrictions: The index plus the width of the mask must not be greater than
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* 31.
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*/
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typedef struct bitfield_field32 {
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/** The field mask. Usually all ones. */
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uint32_t mask;
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/** The field position in the bitfield, counting from the zero-bit. */
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uint32_t index;
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} bitfield_field32_t;
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/**
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* Reads a value from `field` in `bitfield`.
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*
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* This function uses the `field` parameter to read the value from `bitfield`.
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* The resulting value will be shifted right and zero-extended so the field's
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* zero-bit is the return value's zero-bit.
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*
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* @param bitfield Bitfield to get the field from.
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* @param field Field to read out from.
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* @return Zero-extended `field` from `bitfield`.
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*/
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BITFIELD_WARN_UNUSED_RESULT
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inline uint32_t bitfield_field32_read(uint32_t bitfield,
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bitfield_field32_t field) {
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return (bitfield >> field.index) & field.mask;
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}
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/**
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* Writes `value` to `field` in `bitfield`.
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*
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* This function uses the `field` parameter to set specific bits in `bitfield`.
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* The relevant portion of `bitfield` is zeroed before the bits are set to
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* `value`.
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*
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* @param bitfield Bitfield to set the field in.
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* @param field Field within bitfield to be set.
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* @param value Value for the new field.
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* @return `bitfield` with `field` set to `value`.
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*/
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BITFIELD_WARN_UNUSED_RESULT
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inline uint32_t bitfield_field32_write(uint32_t bitfield,
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bitfield_field32_t field,
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uint32_t value) {
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bitfield &= ~(field.mask << field.index);
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bitfield |= (value & field.mask) << field.index;
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return bitfield;
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}
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/**
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* A single bit in a 32-bit bitfield.
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*
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* This denotes the position of a single bit, counting from the zero-bit.
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*
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* For instance, `(bitfield_bit_index_t)4` denotes the X-marked bit in the
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* following 32-bit bitfield:
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*
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* field: 0b--------'--------'--------'---X----
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* index: 31 0
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*
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* Restrictions: The value must not be greater than 31.
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*/
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typedef uint32_t bitfield_bit32_index_t;
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/**
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* Turns a `bitfield_bit32_index_t` into a `bitfield_field32_t` (which is more
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* general).
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*
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* @param bit_index The corresponding single bit to turn into a field.
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* @return A 1-bit field that corresponds to `bit_index`.
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*/
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BITFIELD_WARN_UNUSED_RESULT
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inline bitfield_field32_t bitfield_bit32_to_field32(
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bitfield_bit32_index_t bit_index) {
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return (bitfield_field32_t){
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.mask = 0x1, .index = bit_index,
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};
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}
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/**
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* Reads the `bit_index`th bit in `bitfield`.
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*
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* @param bitfield Bitfield to get the bit from.
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* @param bit_index Bit to read.
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* @return `true` if the bit was one, `false` otherwise.
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*/
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BITFIELD_WARN_UNUSED_RESULT
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inline bool bitfield_bit32_read(uint32_t bitfield,
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bitfield_bit32_index_t bit_index) {
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return bitfield_field32_read(bitfield,
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bitfield_bit32_to_field32(bit_index)) == 0x1u;
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}
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/**
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* Writes `value` to the `bit_index`th bit in `bitfield`.
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*
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* @param bitfield Bitfield to update the bit in.
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* @param bit_index Bit to update.
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* @param value Bit value to write to `bitfield`.
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* @return `bitfield` with the `bit_index`th bit set to `value`.
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*/
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BITFIELD_WARN_UNUSED_RESULT
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inline uint32_t bitfield_bit32_write(uint32_t bitfield,
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bitfield_bit32_index_t bit_index,
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bool value) {
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return bitfield_field32_write(bitfield, bitfield_bit32_to_field32(bit_index),
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value ? 0x1u : 0x0u);
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}
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/**
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* Find First Set Bit
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*
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* Returns one plus the index of the least-significant 1-bit of a 32-bit word.
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*
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* For instance, `bitfield_find_first_set32(field)` of the below 32-bit value
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* returns `5`.
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*
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* field: 0b00000000'00000000'11111111'00010000
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* index: 31 0
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*
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* This is the canonical definition for the GCC/Clang builtin `__builtin_ffs`,
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* and hence takes and returns a signed integer.
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*
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* @param bitfield Bitfield to find the first set bit in.
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* @return One plus the index of the least-significant 1-bit of `bitfield`.
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*/
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BITFIELD_WARN_UNUSED_RESULT
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inline int32_t bitfield_find_first_set32(int32_t bitfield) {
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return __builtin_ffs(bitfield);
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}
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/**
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* Count Leading Zeroes
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*
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* Returns the number of leading 0-bits in `bitfield`, starting at the most
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* significant bit position. If `bitfield` is 0, the result is 32, to match the
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* RISC-V B Extension.
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*
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* For instance, `bitfield_count_leading_zeroes32(field)` of the below 32-bit
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* value returns `16`.
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*
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* field: 0b00000000'00000000'11111111'00010000
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* index: 31 0
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*
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* This is the canonical definition for the GCC/Clang builtin `__builtin_clz`,
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* and hence returns a signed integer.
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*
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* @param bitfield Bitfield to count leading 0-bits from.
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* @return The number of leading 0-bits in `bitfield`.
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*/
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BITFIELD_WARN_UNUSED_RESULT
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inline int32_t bitfield_count_leading_zeroes32(uint32_t bitfield) {
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return (bitfield != 0) ? __builtin_clz(bitfield) : 32;
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}
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/**
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* Count Trailing Zeroes
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*
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* Returns the number of trailing 0-bits in `bitfield`, starting at the least
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* significant bit position. If `bitfield` is 0, the result is 32, to match the
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* RISC-V B Extension.
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*
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* For instance, `bitfield_count_trailing_zeroes32(field)` of the below 32-bit
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* value returns `4`.
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*
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* field: 0b00000000'00000000'11111111'00010000
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* index: 31 0
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*
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* This is the canonical definition for the GCC/Clang builtin `__builtin_ctz`,
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* and hence returns a signed integer.
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*
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* @param bitfield Bitfield to count trailing 0-bits from.
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* @return The number of trailing 0-bits in `bitfield`.
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*/
|
||||
BITFIELD_WARN_UNUSED_RESULT
|
||||
inline int32_t bitfield_count_trailing_zeroes32(uint32_t bitfield) {
|
||||
return (bitfield != 0) ? __builtin_ctz(bitfield) : 32;
|
||||
}
|
||||
|
||||
/**
|
||||
* Count Set Bits
|
||||
*
|
||||
* Returns the number of 1-bits in `bitfield`.
|
||||
*
|
||||
* For instance, `bitfield_popcount32(field)` of the below 32-bit value returns
|
||||
* `9`.
|
||||
*
|
||||
* field: 0b00000000'00000000'11111111'00010000
|
||||
* index: 31 0
|
||||
*
|
||||
* This is the canonical definition for the GCC/Clang builtin
|
||||
* `__builtin_popcount`, and hence returns a signed integer.
|
||||
*
|
||||
* @param bitfield Bitfield to count 1-bits from.
|
||||
* @return The number of 1-bits in `bitfield`.
|
||||
*/
|
||||
BITFIELD_WARN_UNUSED_RESULT
|
||||
inline int32_t bitfield_popcount32(uint32_t bitfield) {
|
||||
return __builtin_popcount(bitfield);
|
||||
}
|
||||
|
||||
/**
|
||||
* Parity
|
||||
*
|
||||
* Returns the number of 1-bits in `bitfield`, modulo 2.
|
||||
*
|
||||
* For instance, `bitfield_parity32(field)` of the below 32-bit value returns
|
||||
* `1`.
|
||||
*
|
||||
* field: 0b00000000'00000000'11111111'00010000
|
||||
* index: 31 0
|
||||
*
|
||||
* This is the canonical definition for the GCC/Clang builtin
|
||||
* `__builtin_parity`, and hence returns a signed integer.
|
||||
*
|
||||
* @param bitfield Bitfield to count 1-bits from.
|
||||
* @return The number of 1-bits in `bitfield`, modulo 2.
|
||||
*/
|
||||
BITFIELD_WARN_UNUSED_RESULT
|
||||
inline int32_t bitfield_parity32(uint32_t bitfield) {
|
||||
return __builtin_parity(bitfield);
|
||||
}
|
||||
|
||||
/**
|
||||
* Byte Swap
|
||||
*
|
||||
* Returns `field` with the order of the bytes reversed. Bytes here always means
|
||||
* exactly 8 bits.
|
||||
*
|
||||
* For instance, `byteswap(field)` of the below 32-bit value returns `1`.
|
||||
*
|
||||
* field: 0bAAAAAAAA'BBBBBBBB'CCCCCCCC'DDDDDDDD
|
||||
* index: 31 0
|
||||
* returns: 0bDDDDDDDD'CCCCCCCC'BBBBBBBB'AAAAAAAA
|
||||
*
|
||||
* This is the canonical definition for the GCC/Clang builtin
|
||||
* `__builtin_bswap32`.
|
||||
*
|
||||
* @param bitfield Bitfield to reverse bytes of.
|
||||
* @return `bitfield` with the order of bytes reversed.
|
||||
*/
|
||||
BITFIELD_WARN_UNUSED_RESULT
|
||||
inline uint32_t bitfield_byteswap32(uint32_t bitfield) {
|
||||
return __builtin_bswap32(bitfield);
|
||||
}
|
||||
|
||||
#ifdef __cplusplus
|
||||
} // extern "C"
|
||||
#endif // __cplusplus
|
||||
|
||||
#endif // OPENTITAN_SW_DEVICE_LIB_BASE_BITFIELD_H_
|
||||
Loading…
Reference in a new issue