diff options
Diffstat (limited to 'drivers/mfd/vexpress-sysreg.c')
| -rw-r--r-- | drivers/mfd/vexpress-sysreg.c | 475 |
1 files changed, 475 insertions, 0 deletions
diff --git a/drivers/mfd/vexpress-sysreg.c b/drivers/mfd/vexpress-sysreg.c new file mode 100644 index 000000000000..733c06bd2d17 --- /dev/null +++ b/drivers/mfd/vexpress-sysreg.c @@ -0,0 +1,475 @@ +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * 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. + * + * Copyright (C) 2012 ARM Limited + */ + +#include <linux/err.h> +#include <linux/gpio.h> +#include <linux/io.h> +#include <linux/leds.h> +#include <linux/of_address.h> +#include <linux/platform_device.h> +#include <linux/regulator/driver.h> +#include <linux/slab.h> +#include <linux/stat.h> +#include <linux/timer.h> +#include <linux/vexpress.h> + +#define SYS_ID 0x000 +#define SYS_SW 0x004 +#define SYS_LED 0x008 +#define SYS_100HZ 0x024 +#define SYS_FLAGS 0x030 +#define SYS_FLAGSSET 0x030 +#define SYS_FLAGSCLR 0x034 +#define SYS_NVFLAGS 0x038 +#define SYS_NVFLAGSSET 0x038 +#define SYS_NVFLAGSCLR 0x03c +#define SYS_MCI 0x048 +#define SYS_FLASH 0x04c +#define SYS_CFGSW 0x058 +#define SYS_24MHZ 0x05c +#define SYS_MISC 0x060 +#define SYS_DMA 0x064 +#define SYS_PROCID0 0x084 +#define SYS_PROCID1 0x088 +#define SYS_CFGDATA 0x0a0 +#define SYS_CFGCTRL 0x0a4 +#define SYS_CFGSTAT 0x0a8 + +#define SYS_HBI_MASK 0xfff +#define SYS_ID_HBI_SHIFT 16 +#define SYS_PROCIDx_HBI_SHIFT 0 + +#define SYS_MCI_CARDIN (1 << 0) +#define SYS_MCI_WPROT (1 << 1) + +#define SYS_FLASH_WPn (1 << 0) + +#define SYS_MISC_MASTERSITE (1 << 14) + +#define SYS_CFGCTRL_START (1 << 31) +#define SYS_CFGCTRL_WRITE (1 << 30) +#define SYS_CFGCTRL_DCC(n) (((n) & 0xf) << 26) +#define SYS_CFGCTRL_FUNC(n) (((n) & 0x3f) << 20) +#define SYS_CFGCTRL_SITE(n) (((n) & 0x3) << 16) +#define SYS_CFGCTRL_POSITION(n) (((n) & 0xf) << 12) +#define SYS_CFGCTRL_DEVICE(n) (((n) & 0xfff) << 0) + +#define SYS_CFGSTAT_ERR (1 << 1) +#define SYS_CFGSTAT_COMPLETE (1 << 0) + + +static void __iomem *vexpress_sysreg_base; +static struct device *vexpress_sysreg_dev; +static int vexpress_master_site; + + +void vexpress_flags_set(u32 data) +{ + writel(~0, vexpress_sysreg_base + SYS_FLAGSCLR); + writel(data, vexpress_sysreg_base + SYS_FLAGSSET); +} + +u32 vexpress_get_procid(int site) +{ + if (site == VEXPRESS_SITE_MASTER) + site = vexpress_master_site; + + return readl(vexpress_sysreg_base + (site == VEXPRESS_SITE_DB1 ? + SYS_PROCID0 : SYS_PROCID1)); +} + +u32 vexpress_get_hbi(int site) +{ + u32 id; + + switch (site) { + case VEXPRESS_SITE_MB: + id = readl(vexpress_sysreg_base + SYS_ID); + return (id >> SYS_ID_HBI_SHIFT) & SYS_HBI_MASK; + case VEXPRESS_SITE_MASTER: + case VEXPRESS_SITE_DB1: + case VEXPRESS_SITE_DB2: + id = vexpress_get_procid(site); + return (id >> SYS_PROCIDx_HBI_SHIFT) & SYS_HBI_MASK; + } + + return ~0; +} + +void __iomem *vexpress_get_24mhz_clock_base(void) +{ + return vexpress_sysreg_base + SYS_24MHZ; +} + + +static void vexpress_sysreg_find_prop(struct device_node *node, + const char *name, u32 *val) +{ + of_node_get(node); + while (node) { + if (of_property_read_u32(node, name, val) == 0) { + of_node_put(node); + return; + } + node = of_get_next_parent(node); + } +} + +unsigned __vexpress_get_site(struct device *dev, struct device_node *node) +{ + u32 site = 0; + + WARN_ON(dev && node && dev->of_node != node); + if (dev && !node) + node = dev->of_node; + + if (node) { + vexpress_sysreg_find_prop(node, "arm,vexpress,site", &site); + } else if (dev && dev->bus == &platform_bus_type) { + struct platform_device *pdev = to_platform_device(dev); + + if (pdev->num_resources == 1 && + pdev->resource[0].flags == IORESOURCE_BUS) + site = pdev->resource[0].start; + } else if (dev && strncmp(dev_name(dev), "ct:", 3) == 0) { + site = VEXPRESS_SITE_MASTER; + } + + if (site == VEXPRESS_SITE_MASTER) + site = vexpress_master_site; + + return site; +} + + +struct vexpress_sysreg_config_func { + u32 template; + u32 device; +}; + +static struct vexpress_config_bridge *vexpress_sysreg_config_bridge; +static struct timer_list vexpress_sysreg_config_timer; +static u32 *vexpress_sysreg_config_data; +static int vexpress_sysreg_config_tries; + +static void *vexpress_sysreg_config_func_get(struct device *dev, + struct device_node *node) +{ + struct vexpress_sysreg_config_func *config_func; + u32 site; + u32 position = 0; + u32 dcc = 0; + u32 func_device[2]; + int err = -EFAULT; + + if (node) { + of_node_get(node); + vexpress_sysreg_find_prop(node, "arm,vexpress,site", &site); + vexpress_sysreg_find_prop(node, "arm,vexpress,position", + &position); + vexpress_sysreg_find_prop(node, "arm,vexpress,dcc", &dcc); + err = of_property_read_u32_array(node, + "arm,vexpress-sysreg,func", func_device, + ARRAY_SIZE(func_device)); + of_node_put(node); + } else if (dev && dev->bus == &platform_bus_type) { + struct platform_device *pdev = to_platform_device(dev); + + if (pdev->num_resources == 1 && + pdev->resource[0].flags == IORESOURCE_BUS) { + site = pdev->resource[0].start; + func_device[0] = pdev->resource[0].end; + func_device[1] = pdev->id; + err = 0; + } + } + if (err) + return NULL; + + config_func = kzalloc(sizeof(*config_func), GFP_KERNEL); + if (!config_func) + return NULL; + + config_func->template = SYS_CFGCTRL_DCC(dcc); + config_func->template |= SYS_CFGCTRL_FUNC(func_device[0]); + config_func->template |= SYS_CFGCTRL_SITE(site == VEXPRESS_SITE_MASTER ? + vexpress_master_site : site); + config_func->template |= SYS_CFGCTRL_POSITION(position); + config_func->device |= func_device[1]; + + dev_dbg(vexpress_sysreg_dev, "func 0x%p = 0x%x, %d\n", config_func, + config_func->template, config_func->device); + + return config_func; +} + +static void vexpress_sysreg_config_func_put(void *func) +{ + kfree(func); +} + +static int vexpress_sysreg_config_func_exec(void *func, int offset, + bool write, u32 *data) +{ + int status; + struct vexpress_sysreg_config_func *config_func = func; + u32 command; + + if (WARN_ON(!vexpress_sysreg_base)) + return -ENOENT; + + command = readl(vexpress_sysreg_base + SYS_CFGCTRL); + if (WARN_ON(command & SYS_CFGCTRL_START)) + return -EBUSY; + + command = SYS_CFGCTRL_START; + command |= write ? SYS_CFGCTRL_WRITE : 0; + command |= config_func->template; + command |= SYS_CFGCTRL_DEVICE(config_func->device + offset); + + /* Use a canary for reads */ + if (!write) + *data = 0xdeadbeef; + + dev_dbg(vexpress_sysreg_dev, "command %x, data %x\n", + command, *data); + writel(*data, vexpress_sysreg_base + SYS_CFGDATA); + writel(0, vexpress_sysreg_base + SYS_CFGSTAT); + writel(command, vexpress_sysreg_base + SYS_CFGCTRL); + mb(); + + if (vexpress_sysreg_dev) { + /* Schedule completion check */ + if (!write) + vexpress_sysreg_config_data = data; + vexpress_sysreg_config_tries = 100; + mod_timer(&vexpress_sysreg_config_timer, + jiffies + usecs_to_jiffies(100)); + status = VEXPRESS_CONFIG_STATUS_WAIT; + } else { + /* Early execution, no timer available, have to spin */ + u32 cfgstat; + + do { + cpu_relax(); + cfgstat = readl(vexpress_sysreg_base + SYS_CFGSTAT); + } while (!cfgstat); + + if (!write && (cfgstat & SYS_CFGSTAT_COMPLETE)) + *data = readl(vexpress_sysreg_base + SYS_CFGDATA); + status = VEXPRESS_CONFIG_STATUS_DONE; + + if (cfgstat & SYS_CFGSTAT_ERR) + status = -EINVAL; + } + + return status; +} + +struct vexpress_config_bridge_info vexpress_sysreg_config_bridge_info = { + .name = "vexpress-sysreg", + .func_get = vexpress_sysreg_config_func_get, + .func_put = vexpress_sysreg_config_func_put, + .func_exec = vexpress_sysreg_config_func_exec, +}; + +static void vexpress_sysreg_config_complete(unsigned long data) +{ + int status = VEXPRESS_CONFIG_STATUS_DONE; + u32 cfgstat = readl(vexpress_sysreg_base + SYS_CFGSTAT); + + if (cfgstat & SYS_CFGSTAT_ERR) + status = -EINVAL; + if (!vexpress_sysreg_config_tries--) + status = -ETIMEDOUT; + + if (status < 0) { + dev_err(vexpress_sysreg_dev, "error %d\n", status); + } else if (!(cfgstat & SYS_CFGSTAT_COMPLETE)) { + mod_timer(&vexpress_sysreg_config_timer, + jiffies + usecs_to_jiffies(50)); + return; + } + + if (vexpress_sysreg_config_data) { + *vexpress_sysreg_config_data = readl(vexpress_sysreg_base + + SYS_CFGDATA); + dev_dbg(vexpress_sysreg_dev, "read data %x\n", + *vexpress_sysreg_config_data); + vexpress_sysreg_config_data = NULL; + } + + vexpress_config_complete(vexpress_sysreg_config_bridge, status); +} + + +void __init vexpress_sysreg_early_init(void __iomem *base) +{ + struct device_node *node = of_find_compatible_node(NULL, NULL, + "arm,vexpress-sysreg"); + + if (node) + base = of_iomap(node, 0); + + if (WARN_ON(!base)) + return; + + vexpress_sysreg_base = base; + + if (readl(vexpress_sysreg_base + SYS_MISC) & SYS_MISC_MASTERSITE) + vexpress_master_site = VEXPRESS_SITE_DB2; + else + vexpress_master_site = VEXPRESS_SITE_DB1; + + vexpress_sysreg_config_bridge = vexpress_config_bridge_register( + node, &vexpress_sysreg_config_bridge_info); + WARN_ON(!vexpress_sysreg_config_bridge); +} + +void __init vexpress_sysreg_of_early_init(void) +{ + vexpress_sysreg_early_init(NULL); +} + + +static struct vexpress_sysreg_gpio { + unsigned long reg; + u32 value; +} vexpress_sysreg_gpios[] = { + [VEXPRESS_GPIO_MMC_CARDIN] = { + .reg = SYS_MCI, + .value = SYS_MCI_CARDIN, + }, + [VEXPRESS_GPIO_MMC_WPROT] = { + .reg = SYS_MCI, + .value = SYS_MCI_WPROT, + }, + [VEXPRESS_GPIO_FLASH_WPn] = { + .reg = SYS_FLASH, + .value = SYS_FLASH_WPn, + }, +}; + +static int vexpress_sysreg_gpio_direction_input(struct gpio_chip *chip, + unsigned offset) +{ + return 0; +} + +static int vexpress_sysreg_gpio_direction_output(struct gpio_chip *chip, + unsigned offset, int value) +{ + return 0; +} + +static int vexpress_sysreg_gpio_get(struct gpio_chip *chip, + unsigned offset) +{ + struct vexpress_sysreg_gpio *gpio = &vexpress_sysreg_gpios[offset]; + u32 reg_value = readl(vexpress_sysreg_base + gpio->reg); + + return !!(reg_value & gpio->value); +} + +static void vexpress_sysreg_gpio_set(struct gpio_chip *chip, + unsigned offset, int value) +{ + struct vexpress_sysreg_gpio *gpio = &vexpress_sysreg_gpios[offset]; + u32 reg_value = readl(vexpress_sysreg_base + gpio->reg); + + if (value) + reg_value |= gpio->value; + else + reg_value &= ~gpio->value; + + writel(reg_value, vexpress_sysreg_base + gpio->reg); +} + +static struct gpio_chip vexpress_sysreg_gpio_chip = { + .label = "vexpress-sysreg", + .direction_input = vexpress_sysreg_gpio_direction_input, + .direction_output = vexpress_sysreg_gpio_direction_output, + .get = vexpress_sysreg_gpio_get, + .set = vexpress_sysreg_gpio_set, + .ngpio = ARRAY_SIZE(vexpress_sysreg_gpios), + .base = 0, +}; + + +static ssize_t vexpress_sysreg_sys_id_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "0x%08x\n", readl(vexpress_sysreg_base + SYS_ID)); +} + +DEVICE_ATTR(sys_id, S_IRUGO, vexpress_sysreg_sys_id_show, NULL); + +static int __devinit vexpress_sysreg_probe(struct platform_device *pdev) +{ + int err; + struct resource *res = platform_get_resource(pdev, + IORESOURCE_MEM, 0); + + if (!devm_request_mem_region(&pdev->dev, res->start, + resource_size(res), pdev->name)) { + dev_err(&pdev->dev, "Failed to request memory region!\n"); + return -EBUSY; + } + + if (!vexpress_sysreg_base) + vexpress_sysreg_base = devm_ioremap(&pdev->dev, res->start, + resource_size(res)); + + if (!vexpress_sysreg_base) { + dev_err(&pdev->dev, "Failed to obtain base address!\n"); + return -EFAULT; + } + + setup_timer(&vexpress_sysreg_config_timer, + vexpress_sysreg_config_complete, 0); + + vexpress_sysreg_gpio_chip.dev = &pdev->dev; + err = gpiochip_add(&vexpress_sysreg_gpio_chip); + if (err) { + vexpress_config_bridge_unregister( + vexpress_sysreg_config_bridge); + dev_err(&pdev->dev, "Failed to register GPIO chip! (%d)\n", + err); + return err; + } + + vexpress_sysreg_dev = &pdev->dev; + + device_create_file(vexpress_sysreg_dev, &dev_attr_sys_id); + + return 0; +} + +static const struct of_device_id vexpress_sysreg_match[] = { + { .compatible = "arm,vexpress-sysreg", }, + {}, +}; + +static struct platform_driver vexpress_sysreg_driver = { + .driver = { + .name = "vexpress-sysreg", + .of_match_table = vexpress_sysreg_match, + }, + .probe = vexpress_sysreg_probe, +}; + +static int __init vexpress_sysreg_init(void) +{ + return platform_driver_register(&vexpress_sysreg_driver); +} +core_initcall(vexpress_sysreg_init); |