mfd: Versatile Express system registers driver
[firefly-linux-kernel-4.4.55.git] / drivers / mfd / vexpress-sysreg.c
diff --git a/drivers/mfd/vexpress-sysreg.c b/drivers/mfd/vexpress-sysreg.c
new file mode 100644 (file)
index 0000000..059d6b1
--- /dev/null
@@ -0,0 +1,552 @@
+/*
+ * 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);
+
+
+#if defined(CONFIG_LEDS_CLASS)
+
+struct vexpress_sysreg_led {
+       u32 mask;
+       struct led_classdev cdev;
+} vexpress_sysreg_leds[] = {
+       { .mask = 1 << 0, .cdev.name = "v2m:green:user1",
+                       .cdev.default_trigger = "heartbeat", },
+       { .mask = 1 << 1, .cdev.name = "v2m:green:user2",
+                       .cdev.default_trigger = "mmc0", },
+       { .mask = 1 << 2, .cdev.name = "v2m:green:user3",
+                       .cdev.default_trigger = "cpu0", },
+       { .mask = 1 << 3, .cdev.name = "v2m:green:user4",
+                       .cdev.default_trigger = "cpu1", },
+       { .mask = 1 << 4, .cdev.name = "v2m:green:user5",
+                       .cdev.default_trigger = "cpu2", },
+       { .mask = 1 << 5, .cdev.name = "v2m:green:user6",
+                       .cdev.default_trigger = "cpu3", },
+       { .mask = 1 << 6, .cdev.name = "v2m:green:user7",
+                       .cdev.default_trigger = "cpu4", },
+       { .mask = 1 << 7, .cdev.name = "v2m:green:user8",
+                       .cdev.default_trigger = "cpu5", },
+};
+
+static DEFINE_SPINLOCK(vexpress_sysreg_leds_lock);
+
+static void vexpress_sysreg_led_brightness_set(struct led_classdev *cdev,
+               enum led_brightness brightness)
+{
+       struct vexpress_sysreg_led *led = container_of(cdev,
+                       struct vexpress_sysreg_led, cdev);
+       unsigned long flags;
+       u32 val;
+
+       spin_lock_irqsave(&vexpress_sysreg_leds_lock, flags);
+
+       val = readl(vexpress_sysreg_base + SYS_LED);
+       if (brightness == LED_OFF)
+               val &= ~led->mask;
+       else
+               val |= led->mask;
+       writel(val, vexpress_sysreg_base + SYS_LED);
+
+       spin_unlock_irqrestore(&vexpress_sysreg_leds_lock, flags);
+}
+
+static int __init vexpress_sysreg_init_leds(void)
+{
+       struct vexpress_sysreg_led *led;
+       int i;
+
+       /* Clear all user LEDs */
+       writel(0, vexpress_sysreg_base + SYS_LED);
+
+       for (i = 0, led = vexpress_sysreg_leds;
+                       i < ARRAY_SIZE(vexpress_sysreg_leds); i++, led++) {
+               int err;
+
+               led->cdev.brightness_set = vexpress_sysreg_led_brightness_set;
+               err = led_classdev_register(vexpress_sysreg_dev, &led->cdev);
+               if (err) {
+                       dev_err(vexpress_sysreg_dev,
+                                       "Failed to register LED %d! (%d)\n",
+                                       i, err);
+                       while (led--, i--)
+                               led_classdev_unregister(&led->cdev);
+                       return err;
+               }
+       }
+
+       return 0;
+}
+device_initcall(vexpress_sysreg_init_leds);
+
+#endif