u-boot/drivers/gpio/altera_pio.c

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/*
* Driver for Altera's PIO ip core
*
* Copyright (C) 2011 Missing Link Electronics
* Joachim Foerster <joachim@missinglinkelectronics.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*
* To use this driver, in your board's config. header:
* #define CONFIG_ALTERA_PIO
* #define CONFIG_SYS_ALTERA_PIO_NUM <number-of-pio-cores>
* #define CONFIG_SYS_ALTERA_PIO_GPIO_NUM <total-number-of-gpios>
* And in your board's early setup routine:
* altera_pio_init(<baseaddr>, <width>, 'i'|'o'|'t',
* <reset-value>, <neg-mask>, "label");
* - 'i'|'o'|'t': PIO is input-only/output-only/tri-state
* - <reset-value>: for correct initial status display, output-only
* - <neg-mask> is meant to be used to in cases of active-low
* GPIOs, such as LEDs and buttons (on/pressed == 0). Each bit
* which is 1 in <neg-mask> inverts the corresponding GPIO's value
* before set/after get. So: gpio_set_value(gpio, 1) => LED on .
*
* Do NOT define CONFIG_SYS_GPIO_BASE !
*
* Optionally, in your board's config. header:
* - To force a GPIO numbering scheme like in Linux ...
* #define CONFIG_GPIO_DOWNTO_NUMBERING
* ... starting with 255 (default)
* #define CONFIG_GPIO_DOWNTO_MAX 255
*/
#include <common.h>
#include <asm/io.h>
#include <asm/gpio.h>
#ifdef CONFIG_GPIO_DOWNTO_NUMBERING
#ifndef CONFIG_GPIO_DOWNTO_MAX
#define CONFIG_GPIO_DOWNTO_MAX 255
#endif
#endif
#define ALTERA_PIO_DATA 0x0
#define ALTERA_PIO_DIR 0x4
#define GPIO_LABEL_SIZE 9
static struct altera_pio {
u32 base;
u8 width;
char iot;
u32 negmask;
u32 sh_data;
u32 sh_dir;
int gidx;
char label[GPIO_LABEL_SIZE];
} pios[CONFIG_SYS_ALTERA_PIO_NUM];
static int pio_num;
static struct altera_pio_gpio {
unsigned num;
struct altera_pio *pio;
char reqlabel[GPIO_LABEL_SIZE];
} gpios[CONFIG_SYS_ALTERA_PIO_GPIO_NUM];
static int pio_gpio_num;
static int altera_pio_gidx(unsigned gpio)
{
int i;
for (i = 0; i < pio_gpio_num; ++i) {
if (gpio == gpios[i].num)
break;
}
if (i >= pio_gpio_num)
return -1;
return i;
}
static struct altera_pio *altera_pio_get_and_mask(unsigned gpio, u32 *mask)
{
int gidx = altera_pio_gidx(gpio);
if (gidx < 0)
return NULL;
if (mask)
*mask = 1 << (gidx - gpios[gidx].pio->gidx);
return gpios[gidx].pio;
}
#define altera_pio_use_gidx(_gidx, _reqlabel) \
{ strncpy(gpios[_gidx].reqlabel, _reqlabel, GPIO_LABEL_SIZE); }
#define altera_pio_unuse_gidx(_gidx) { gpios[_gidx].reqlabel[0] = '\0'; }
#define altera_pio_is_gidx_used(_gidx) (gpios[_gidx].reqlabel[0] != '\0')
static int altera_pio_gpio_init(struct altera_pio *pio, u8 width)
{
u8 gidx = pio_gpio_num;
int i;
if (!width)
return -1;
if ((pio_gpio_num + width) > CONFIG_SYS_ALTERA_PIO_GPIO_NUM)
return -1;
for (i = 0; i < width; ++i) {
#ifdef CONFIG_GPIO_DOWNTO_NUMBERING
gpios[pio_gpio_num + i].num = \
CONFIG_GPIO_DOWNTO_MAX + 1 - gidx - width + i;
#else
gpios[pio_gpio_num + i].num = pio_gpio_num + i;
#endif
gpios[pio_gpio_num + i].pio = pio;
altera_pio_unuse_gidx(pio_gpio_num + i);
}
pio_gpio_num += width;
return gidx;
}
int altera_pio_init(u32 base, u8 width, char iot, u32 rstval, u32 negmask,
const char *label)
{
if (pio_num >= CONFIG_SYS_ALTERA_PIO_NUM)
return -1;
pios[pio_num].base = base;
pios[pio_num].width = width;
pios[pio_num].iot = iot;
switch (iot) {
case 'i':
/* input only */
pios[pio_num].sh_dir = 0;
pios[pio_num].sh_data = readl(base + ALTERA_PIO_DATA);
break;
case 'o':
/* output only */
pios[pio_num].sh_dir = 0xffffffff & ((1 << width) - 1);
pios[pio_num].sh_data = rstval;
break;
case 't':
/* bidir, tri-state */
pios[pio_num].sh_dir = readl(base + ALTERA_PIO_DIR);
pios[pio_num].sh_data = readl(base + ALTERA_PIO_DATA);
break;
default:
return -1;
}
pios[pio_num].negmask = negmask & ((1 << width) - 1);
pios[pio_num].gidx = altera_pio_gpio_init(&pios[pio_num], width);
if (pios[pio_num].gidx < 0)
return -1;
strncpy(pios[pio_num].label, label, GPIO_LABEL_SIZE);
return pio_num++;
}
void altera_pio_info(void)
{
int i;
int j;
int gidx;
u32 mask;
for (i = 0; i < pio_num; ++i) {
printf("Altera PIO % 2d, @0x%08x, "
"width: %u, label: %s\n",
i, pios[i].base, pios[i].width, pios[i].label);
gidx = pios[i].gidx;
for (j = gidx; j < (gidx + pios[i].width); ++j) {
mask = 1 << (j - gidx);
printf("\tGPIO % 4d: %s %s [%c] %s\n",
gpios[j].num,
gpios[j].pio->sh_dir & mask ? "out" : " in",
gpio_get_value(gpios[j].num) ? "set" : "clr",
altera_pio_is_gidx_used(j) ? 'x' : ' ',
gpios[j].reqlabel);
}
}
}
int gpio_request(unsigned gpio, const char *label)
{
int gidx = altera_pio_gidx(gpio);
if (gidx < 0)
return gidx;
if (altera_pio_is_gidx_used(gidx))
return -1;
altera_pio_use_gidx(gidx, label);
return 0;
}
int gpio_free(unsigned gpio)
{
int gidx = altera_pio_gidx(gpio);
if (gidx < 0)
return gidx;
if (!altera_pio_is_gidx_used(gidx))
return -1;
altera_pio_unuse_gidx(gidx);
return 0;
}
int gpio_direction_input(unsigned gpio)
{
u32 mask;
struct altera_pio *pio;
pio = altera_pio_get_and_mask(gpio, &mask);
if (!pio)
return -1;
if (pio->iot == 'o')
return -1;
writel(pio->sh_dir &= ~mask, pio->base + ALTERA_PIO_DIR);
return 0;
}
int gpio_direction_output(unsigned gpio, int value)
{
u32 mask;
struct altera_pio *pio;
pio = altera_pio_get_and_mask(gpio, &mask);
if (!pio)
return -1;
if (pio->iot == 'i')
return -1;
value = (pio->negmask & mask) ? !value : value;
if (value)
pio->sh_data |= mask;
else
pio->sh_data &= ~mask;
writel(pio->sh_data, pio->base + ALTERA_PIO_DATA);
writel(pio->sh_dir |= mask, pio->base + ALTERA_PIO_DIR);
return 0;
}
int gpio_get_value(unsigned gpio)
{
u32 mask;
struct altera_pio *pio;
u32 val;
pio = altera_pio_get_and_mask(gpio, &mask);
if (!pio)
return -1;
if ((pio->sh_dir & mask) || (pio->iot == 'o'))
val = pio->sh_data & mask;
else
val = readl(pio->base + ALTERA_PIO_DATA) & mask;
return (pio->negmask & mask) ? !val : val;
}
void gpio_set_value(unsigned gpio, int value)
{
u32 mask;
struct altera_pio *pio;
pio = altera_pio_get_and_mask(gpio, &mask);
if (!pio)
return;
if (pio->iot == 'i')
return;
value = (pio->negmask & mask) ? !value : value;
if (value)
pio->sh_data |= mask;
else
pio->sh_data &= ~mask;
writel(pio->sh_data, pio->base + ALTERA_PIO_DATA);
return;
}
int gpio_is_valid(int number)
{
int gidx = altera_pio_gidx(number);
if (gidx < 0)
return 1;
return 0;
}