gpio_support.c

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/* SPDX-License-Identifier: GPL-2.0-only */
 
#include <device/mmio.h>
#include <gpio.h>
#include <console/console.h>
#include <soc/gpio.h>
 
/*
 * Return family number and internal pad number in that community by pad number
 * and which community it is in.
 */
uint16_t gpio_family_number(uint8_t community, uint8_t pad)
{
        /*
         * Refer to BSW BIOS Writers Guide, Table "Family Number". BSW has 4 GPIO communities.
         * Each community has up to 7 families and each family contains a range of Pad numbers.
         * The number in the array is the maximum no. of that range.
         * For example: East community, family 0, Pad 0~11.
         */
        static const uint8_t community_base[GPIO_COMMUNITY_COUNT]
                [GPIO_FAMILIES_MAX_PER_COMM + 1] = {
                {0,  8, 16, 24, 32, 40, 48, 56}, /* Southwest */
                {0,  9, 22, 34, 46, 59, 59, 59}, /* North */
                {0, 12, 24, 24, 24, 24, 24, 24}, /* East */
                {0,  8, 20, 26, 34, 44, 55, 55}  /* Southeast */
        };
        const uint8_t *base;
        uint8_t i;
 
        /* Validate the pad number */
        if (pad > community_base[community][7])
                die("Pad number is out of range!");
 
        /* Locate the family number for the pad */
        base = &community_base[community][0];
        for (i = 0; i < 7; i++) {
                if ((pad >= base[0]) && (pad < base[1]))
                        break;
                base++;
        }
 
        /* Family number in high byte and inner pad number in lowest byte */
        return (i << 8) + pad - *base;
}
 
/*
 * Return pad configuration register offset by pad number and which community it is in.
 */
uint32_t *gpio_pad_config_reg(uint8_t community, uint8_t pad)
{
        uint16_t fpad;
        uint32_t *pad_config_reg;
 
        /* Get the GPIO family number */
        fpad = gpio_family_number(community, pad);
 
        /*
         * Refer to BSW BIOS Writers Guide, Table "Per Pad Memory Space Registers Addresses"
         * for the Pad configuration register calculation.
         */
        pad_config_reg = (uint32_t *)(COMMUNITY_BASE(community) + FAMILY_PAD_REGS_OFF +
                (FAMILY_PAD_REGS_SIZE * (fpad >> 8)) + (GPIO_REGS_SIZE * (fpad & 0xff)));
 
        return pad_config_reg;
}
 
static int gpio_get_community_num(gpio_t gpio_num, int *pad)
{
        int comm = 0;
 
        if (gpio_num >= GP_SW_00 && gpio_num <= GP_SW_97) {
                comm =  GP_SOUTHWEST;
                *pad = gpio_num % GP_SOUTHWEST_COUNT;
 
        } else if (gpio_num >= GP_NC_00 && gpio_num <= GP_NC_72) {
                comm =  GP_NORTH;
                *pad = gpio_num % GP_SOUTHWEST_COUNT;
 
        } else if (gpio_num >= GP_E_00 && gpio_num <= GP_E_26) {
                comm =  GP_EAST;
                *pad = gpio_num % (GP_SOUTHWEST_COUNT + GP_NORTH_COUNT);
 
        } else {
                comm = GP_SOUTHEAST;
                *pad = gpio_num % (GP_SOUTHWEST_COUNT + GP_NORTH_COUNT + GP_EAST_COUNT);
        }
        return comm;
}
 
static void gpio_config_pad(gpio_t gpio_num, const struct soc_gpio_map *cfg)
{
        int comm = 0;
        int pad_num = 0;
        uint32_t *pad_config0_reg;
        uint32_t *pad_config1_reg;
 
        if (gpio_num > MAX_GPIO_CNT)
                return;
        /* Get GPIO Community based on GPIO_NUMBER */
        comm = gpio_get_community_num(gpio_num, &pad_num);
        /* CONF0 */
        pad_config0_reg = gpio_pad_config_reg(comm, pad_num);
        /* CONF1 */
        pad_config1_reg = pad_config0_reg + 1;
 
        write32(pad_config0_reg, cfg->pad_conf0);
        write32(pad_config1_reg, cfg->pad_conf1);
}
 
void gpio_input_pullup(gpio_t gpio_num)
{
        struct soc_gpio_map cfg = GPIO_INPUT_PU_20K;
        gpio_config_pad(gpio_num, &cfg);
}
 
void gpio_input_pulldown(gpio_t gpio_num)
{
        struct soc_gpio_map cfg = GPIO_INPUT_PD_20K;
        gpio_config_pad(gpio_num, &cfg);
}
 
void gpio_input(gpio_t gpio_num)
{
        struct soc_gpio_map cfg = GPIO_INPUT_NO_PULL;
        gpio_config_pad(gpio_num, &cfg);
}
 
int gpio_get(gpio_t gpio_num)
{
        int comm = 0;
        int pad_num = 0;
        uint32_t *pad_config0_reg;
        u32 pad_value;
 
        if (gpio_num > MAX_GPIO_CNT)
                return -1;
 
        /* Get GPIO Community based on GPIO_NUMBER */
        comm = gpio_get_community_num(gpio_num, &pad_num);
        /* CONF0 */
        pad_config0_reg = gpio_pad_config_reg(comm, pad_num);
 
        pad_value = read32(pad_config0_reg);
 
        return pad_value & PAD_RX_BIT;
}
 
int get_gpio(int community_base, int pad0_offset)
{
        return (read32((void *)(community_base + pad0_offset))) & PAD_RX_BIT;
}