diff options
Diffstat (limited to 'drivers/bus/vexpress-config.c')
| -rw-r--r-- | drivers/bus/vexpress-config.c | 210 |
1 files changed, 210 insertions, 0 deletions
diff --git a/drivers/bus/vexpress-config.c b/drivers/bus/vexpress-config.c new file mode 100644 index 000000000..493e7b9fc --- /dev/null +++ b/drivers/bus/vexpress-config.c @@ -0,0 +1,210 @@ +/* + * 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) 2014 ARM Limited + */ + +#include <linux/err.h> +#include <linux/init.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/vexpress.h> + + +struct vexpress_config_bridge { + struct vexpress_config_bridge_ops *ops; + void *context; +}; + + +static DEFINE_MUTEX(vexpress_config_mutex); +static struct class *vexpress_config_class; +static u32 vexpress_config_site_master = VEXPRESS_SITE_MASTER; + + +void vexpress_config_set_master(u32 site) +{ + vexpress_config_site_master = site; +} + +u32 vexpress_config_get_master(void) +{ + return vexpress_config_site_master; +} + +void vexpress_config_lock(void *arg) +{ + mutex_lock(&vexpress_config_mutex); +} + +void vexpress_config_unlock(void *arg) +{ + mutex_unlock(&vexpress_config_mutex); +} + + +static void vexpress_config_find_prop(struct device_node *node, + const char *name, u32 *val) +{ + /* Default value */ + *val = 0; + + 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); + } +} + +int vexpress_config_get_topo(struct device_node *node, u32 *site, + u32 *position, u32 *dcc) +{ + vexpress_config_find_prop(node, "arm,vexpress,site", site); + if (*site == VEXPRESS_SITE_MASTER) + *site = vexpress_config_site_master; + if (WARN_ON(vexpress_config_site_master == VEXPRESS_SITE_MASTER)) + return -EINVAL; + vexpress_config_find_prop(node, "arm,vexpress,position", position); + vexpress_config_find_prop(node, "arm,vexpress,dcc", dcc); + + return 0; +} + + +static void vexpress_config_devres_release(struct device *dev, void *res) +{ + struct vexpress_config_bridge *bridge = dev_get_drvdata(dev->parent); + struct regmap *regmap = res; + + bridge->ops->regmap_exit(regmap, bridge->context); +} + +struct regmap *devm_regmap_init_vexpress_config(struct device *dev) +{ + struct vexpress_config_bridge *bridge; + struct regmap *regmap; + struct regmap **res; + + if (WARN_ON(dev->parent->class != vexpress_config_class)) + return ERR_PTR(-ENODEV); + + bridge = dev_get_drvdata(dev->parent); + if (WARN_ON(!bridge)) + return ERR_PTR(-EINVAL); + + res = devres_alloc(vexpress_config_devres_release, sizeof(*res), + GFP_KERNEL); + if (!res) + return ERR_PTR(-ENOMEM); + + regmap = (bridge->ops->regmap_init)(dev, bridge->context); + if (IS_ERR(regmap)) { + devres_free(res); + return regmap; + } + + *res = regmap; + devres_add(dev, res); + + return regmap; +} +EXPORT_SYMBOL_GPL(devm_regmap_init_vexpress_config); + +struct device *vexpress_config_bridge_register(struct device *parent, + struct vexpress_config_bridge_ops *ops, void *context) +{ + struct device *dev; + struct vexpress_config_bridge *bridge; + + if (!vexpress_config_class) { + vexpress_config_class = class_create(THIS_MODULE, + "vexpress-config"); + if (IS_ERR(vexpress_config_class)) + return (void *)vexpress_config_class; + } + + dev = device_create(vexpress_config_class, parent, 0, + NULL, "%s.bridge", dev_name(parent)); + + if (IS_ERR(dev)) + return dev; + + bridge = devm_kmalloc(dev, sizeof(*bridge), GFP_KERNEL); + if (!bridge) { + put_device(dev); + device_unregister(dev); + return ERR_PTR(-ENOMEM); + } + bridge->ops = ops; + bridge->context = context; + + dev_set_drvdata(dev, bridge); + + dev_dbg(parent, "Registered bridge '%s', parent node %p\n", + dev_name(dev), parent->of_node); + + return dev; +} + + +static int vexpress_config_node_match(struct device *dev, const void *data) +{ + const struct device_node *node = data; + + dev_dbg(dev, "Parent node %p, looking for %p\n", + dev->parent->of_node, node); + + return dev->parent->of_node == node; +} + +static int vexpress_config_populate(struct device_node *node) +{ + struct device_node *bridge; + struct device *parent; + int ret; + + bridge = of_parse_phandle(node, "arm,vexpress,config-bridge", 0); + if (!bridge) + return -EINVAL; + + parent = class_find_device(vexpress_config_class, NULL, bridge, + vexpress_config_node_match); + of_node_put(bridge); + if (WARN_ON(!parent)) + return -ENODEV; + + ret = of_platform_populate(node, NULL, NULL, parent); + + put_device(parent); + + return ret; +} + +static int __init vexpress_config_init(void) +{ + int err = 0; + struct device_node *node; + + /* Need the config devices early, before the "normal" devices... */ + for_each_compatible_node(node, NULL, "arm,vexpress,config-bus") { + err = vexpress_config_populate(node); + if (err) { + of_node_put(node); + break; + } + } + + return err; +} +postcore_initcall(vexpress_config_init); + |