cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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gpio.c (3233B)

      1/*
      2 * This file is subject to the terms and conditions of the GNU General Public
      3 * License.  See the file "COPYING" in the main directory of this archive
      4 * for more details.
      5 *
      6 * Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
      7 * Copyright (C) 2008-2011 Florian Fainelli <florian@openwrt.org>
      8 */
      9
     10#include <linux/kernel.h>
     11#include <linux/init.h>
     12#include <linux/spinlock.h>
     13#include <linux/platform_device.h>
     14#include <linux/gpio/driver.h>
     15
     16#include <bcm63xx_cpu.h>
     17#include <bcm63xx_gpio.h>
     18#include <bcm63xx_io.h>
     19#include <bcm63xx_regs.h>
     20
     21static u32 gpio_out_low_reg;
     22
     23static void bcm63xx_gpio_out_low_reg_init(void)
     24{
     25	switch (bcm63xx_get_cpu_id()) {
     26	case BCM6345_CPU_ID:
     27		gpio_out_low_reg = GPIO_DATA_LO_REG_6345;
     28		break;
     29	default:
     30		gpio_out_low_reg = GPIO_DATA_LO_REG;
     31		break;
     32	}
     33}
     34
     35static DEFINE_SPINLOCK(bcm63xx_gpio_lock);
     36static u32 gpio_out_low, gpio_out_high;
     37
     38static void bcm63xx_gpio_set(struct gpio_chip *chip,
     39			     unsigned gpio, int val)
     40{
     41	u32 reg;
     42	u32 mask;
     43	u32 *v;
     44	unsigned long flags;
     45
     46	BUG_ON(gpio >= chip->ngpio);
     47
     48	if (gpio < 32) {
     49		reg = gpio_out_low_reg;
     50		mask = 1 << gpio;
     51		v = &gpio_out_low;
     52	} else {
     53		reg = GPIO_DATA_HI_REG;
     54		mask = 1 << (gpio - 32);
     55		v = &gpio_out_high;
     56	}
     57
     58	spin_lock_irqsave(&bcm63xx_gpio_lock, flags);
     59	if (val)
     60		*v |= mask;
     61	else
     62		*v &= ~mask;
     63	bcm_gpio_writel(*v, reg);
     64	spin_unlock_irqrestore(&bcm63xx_gpio_lock, flags);
     65}
     66
     67static int bcm63xx_gpio_get(struct gpio_chip *chip, unsigned gpio)
     68{
     69	u32 reg;
     70	u32 mask;
     71
     72	BUG_ON(gpio >= chip->ngpio);
     73
     74	if (gpio < 32) {
     75		reg = gpio_out_low_reg;
     76		mask = 1 << gpio;
     77	} else {
     78		reg = GPIO_DATA_HI_REG;
     79		mask = 1 << (gpio - 32);
     80	}
     81
     82	return !!(bcm_gpio_readl(reg) & mask);
     83}
     84
     85static int bcm63xx_gpio_set_direction(struct gpio_chip *chip,
     86				      unsigned gpio, int dir)
     87{
     88	u32 reg;
     89	u32 mask;
     90	u32 tmp;
     91	unsigned long flags;
     92
     93	BUG_ON(gpio >= chip->ngpio);
     94
     95	if (gpio < 32) {
     96		reg = GPIO_CTL_LO_REG;
     97		mask = 1 << gpio;
     98	} else {
     99		reg = GPIO_CTL_HI_REG;
    100		mask = 1 << (gpio - 32);
    101	}
    102
    103	spin_lock_irqsave(&bcm63xx_gpio_lock, flags);
    104	tmp = bcm_gpio_readl(reg);
    105	if (dir == BCM63XX_GPIO_DIR_IN)
    106		tmp &= ~mask;
    107	else
    108		tmp |= mask;
    109	bcm_gpio_writel(tmp, reg);
    110	spin_unlock_irqrestore(&bcm63xx_gpio_lock, flags);
    111
    112	return 0;
    113}
    114
    115static int bcm63xx_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
    116{
    117	return bcm63xx_gpio_set_direction(chip, gpio, BCM63XX_GPIO_DIR_IN);
    118}
    119
    120static int bcm63xx_gpio_direction_output(struct gpio_chip *chip,
    121					 unsigned gpio, int value)
    122{
    123	bcm63xx_gpio_set(chip, gpio, value);
    124	return bcm63xx_gpio_set_direction(chip, gpio, BCM63XX_GPIO_DIR_OUT);
    125}
    126
    127
    128static struct gpio_chip bcm63xx_gpio_chip = {
    129	.label			= "bcm63xx-gpio",
    130	.direction_input	= bcm63xx_gpio_direction_input,
    131	.direction_output	= bcm63xx_gpio_direction_output,
    132	.get			= bcm63xx_gpio_get,
    133	.set			= bcm63xx_gpio_set,
    134	.base			= 0,
    135};
    136
    137int __init bcm63xx_gpio_init(void)
    138{
    139	bcm63xx_gpio_out_low_reg_init();
    140
    141	gpio_out_low = bcm_gpio_readl(gpio_out_low_reg);
    142	if (!BCMCPU_IS_6345())
    143		gpio_out_high = bcm_gpio_readl(GPIO_DATA_HI_REG);
    144	bcm63xx_gpio_chip.ngpio = bcm63xx_gpio_count();
    145	pr_info("registering %d GPIOs\n", bcm63xx_gpio_chip.ngpio);
    146
    147	return gpiochip_add_data(&bcm63xx_gpio_chip, NULL);
    148}