diff options
| -rw-r--r-- | Documentation/devicetree/bindings/arm/vexpress.txt | 68 | ||||
| -rw-r--r-- | drivers/mfd/Kconfig | 6 | ||||
| -rw-r--r-- | drivers/mfd/Makefile | 1 | ||||
| -rw-r--r-- | drivers/mfd/vexpress-config.c | 277 | ||||
| -rw-r--r-- | include/linux/vexpress.h | 85 |
5 files changed, 436 insertions, 1 deletions
diff --git a/Documentation/devicetree/bindings/arm/vexpress.txt b/Documentation/devicetree/bindings/arm/vexpress.txt index ec8b50cbb2e8..5d9996b9eabf 100644 --- a/Documentation/devicetree/bindings/arm/vexpress.txt +++ b/Documentation/devicetree/bindings/arm/vexpress.txt @@ -11,6 +11,10 @@ the motherboard file using a /include/ directive. As the motherboard can be initialized in one of two different configurations ("memory maps"), care must be taken to include the correct one. + +Root node +--------- + Required properties in the root node: - compatible value: compatible = "arm,vexpress,<model>", "arm,vexpress"; @@ -45,6 +49,10 @@ Optional properties in the root node: - Coretile Express A9x4 (V2P-CA9) HBI-0225: arm,hbi = <0x225>; + +CPU nodes +--------- + Top-level standard "cpus" node is required. It must contain a node with device_type = "cpu" property for every available core, eg.: @@ -59,6 +67,52 @@ with device_type = "cpu" property for every available core, eg.: }; }; + +Configuration infrastructure +---------------------------- + +The platform has an elaborated configuration system, consisting of +microcontrollers residing on the mother- and daughterboards known +as Motherboard/Daughterboard Configuration Controller (MCC and DCC). +The controllers are responsible for the platform initialization +(reset generation, flash programming, FPGA bitfiles loading etc.) +but also control clock generators, voltage regulators, gather +environmental data like temperature, power consumption etc. Even +the video output switch (FPGA) is controlled that way. + +Nodes describing devices controlled by this infrastructure should +point at the bridge device node: +- bridge phandle: + arm,vexpress,config-bridge = <phandle>; +This property can be also defined in a parent node (eg. for a DCC) +and is effective for all children. + + +Platform topology +----------------- + +As Versatile Express can be configured in number of physically +different setups, the device tree should describe platform topology. +Root node and main motherboard node must define the following +property, describing physical location of the children nodes: +- site number: + arm,vexpress,site = <number>; + where 0 means motherboard, 1 or 2 are daugtherboard sites, + 0xf means "master" site (site containing main CPU tile) +- when daughterboards are stacked on one site, their position + in the stack be be described with: + arm,vexpress,position = <number>; +- when describing tiles consisting more than one DCC, its number + can be described with: + arm,vexpress,dcc = <number>; + +Any of the numbers above defaults to zero if not defined in +the node or any of its parent. + + +Motherboard +----------- + The motherboard description file provides a single "motherboard" node using 2 address cells corresponding to the Static Memory Bus used between the motherboard and the tile. The first cell defines the Chip @@ -96,13 +150,16 @@ The tile description must define "ranges", "interrupt-map-mask" and "interrupt-map" properties to translate the motherboard's address and interrupt space into one used by the tile's processor. -Abbreviated example: + +Example of a VE tile description (simplified) +--------------------------------------------- /dts-v1/; / { model = "V2P-CA5s"; arm,hbi = <0x225>; + arm,vexpress,site = <0xf>; compatible = "arm,vexpress-v2p-ca5s", "arm,vexpress"; interrupt-parent = <&gic>; #address-cells = <1>; @@ -134,6 +191,15 @@ Abbreviated example: <0x2c000100 0x100>; }; + dcc { + compatible = "simple-bus"; + arm,vexpress,config-bridge = <&v2m_sysreg>; + + osc@0 { + compatible = "arm,vexpress-osc"; + }; + }; + motherboard { /* CS0 is visible at 0x08000000 */ ranges = <0 0 0x08000000 0x04000000>; diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig index acab3ef8a310..637bcdf8ce77 100644 --- a/drivers/mfd/Kconfig +++ b/drivers/mfd/Kconfig @@ -1070,3 +1070,9 @@ config MCP_UCB1200_TS depends on MCP_UCB1200 && INPUT endmenu + +config VEXPRESS_CONFIG + bool + help + Platform configuration infrastructure for the ARM Ltd. + Versatile Express. diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile index d8ccb630ddb0..e807164f68da 100644 --- a/drivers/mfd/Makefile +++ b/drivers/mfd/Makefile @@ -138,3 +138,4 @@ obj-$(CONFIG_MFD_RC5T583) += rc5t583.o rc5t583-irq.o obj-$(CONFIG_MFD_SEC_CORE) += sec-core.o sec-irq.o obj-$(CONFIG_MFD_SYSCON) += syscon.o obj-$(CONFIG_MFD_LM3533) += lm3533-core.o lm3533-ctrlbank.o +obj-$(CONFIG_VEXPRESS_CONFIG) += vexpress-config.o diff --git a/drivers/mfd/vexpress-config.c b/drivers/mfd/vexpress-config.c new file mode 100644 index 000000000000..fae15d880758 --- /dev/null +++ b/drivers/mfd/vexpress-config.c @@ -0,0 +1,277 @@ +/* + * 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 + */ + +#define pr_fmt(fmt) "vexpress-config: " fmt + +#include <linux/bitops.h> +#include <linux/completion.h> +#include <linux/export.h> +#include <linux/init.h> +#include <linux/list.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/vexpress.h> + + +#define VEXPRESS_CONFIG_MAX_BRIDGES 2 + +struct vexpress_config_bridge { + struct device_node *node; + struct vexpress_config_bridge_info *info; + struct list_head transactions; + spinlock_t transactions_lock; +} vexpress_config_bridges[VEXPRESS_CONFIG_MAX_BRIDGES]; + +static DECLARE_BITMAP(vexpress_config_bridges_map, + ARRAY_SIZE(vexpress_config_bridges)); +static DEFINE_MUTEX(vexpress_config_bridges_mutex); + +struct vexpress_config_bridge *vexpress_config_bridge_register( + struct device_node *node, + struct vexpress_config_bridge_info *info) +{ + struct vexpress_config_bridge *bridge; + int i; + + pr_debug("Registering bridge '%s'\n", info->name); + + mutex_lock(&vexpress_config_bridges_mutex); + i = find_first_zero_bit(vexpress_config_bridges_map, + ARRAY_SIZE(vexpress_config_bridges)); + if (i >= ARRAY_SIZE(vexpress_config_bridges)) { + pr_err("Can't register more bridges!\n"); + mutex_unlock(&vexpress_config_bridges_mutex); + return NULL; + } + __set_bit(i, vexpress_config_bridges_map); + bridge = &vexpress_config_bridges[i]; + + bridge->node = node; + bridge->info = info; + INIT_LIST_HEAD(&bridge->transactions); + spin_lock_init(&bridge->transactions_lock); + + mutex_unlock(&vexpress_config_bridges_mutex); + + return bridge; +} + +void vexpress_config_bridge_unregister(struct vexpress_config_bridge *bridge) +{ + struct vexpress_config_bridge __bridge = *bridge; + int i; + + mutex_lock(&vexpress_config_bridges_mutex); + for (i = 0; i < ARRAY_SIZE(vexpress_config_bridges); i++) + if (&vexpress_config_bridges[i] == bridge) + __clear_bit(i, vexpress_config_bridges_map); + mutex_unlock(&vexpress_config_bridges_mutex); + + WARN_ON(!list_empty(&__bridge.transactions)); + while (!list_empty(&__bridge.transactions)) + cpu_relax(); +} + + +struct vexpress_config_func { + struct vexpress_config_bridge *bridge; + void *func; +}; + +struct vexpress_config_func *__vexpress_config_func_get(struct device *dev, + struct device_node *node) +{ + struct device_node *bridge_node; + struct vexpress_config_func *func; + int i; + + if (WARN_ON(dev && node && dev->of_node != node)) + return NULL; + if (dev && !node) + node = dev->of_node; + + func = kzalloc(sizeof(*func), GFP_KERNEL); + if (!func) + return NULL; + + bridge_node = of_node_get(node); + while (bridge_node) { + const __be32 *prop = of_get_property(bridge_node, + "arm,vexpress,config-bridge", NULL); + + if (prop) { + bridge_node = of_find_node_by_phandle( + be32_to_cpup(prop)); + break; + } + + bridge_node = of_get_next_parent(bridge_node); + } + + mutex_lock(&vexpress_config_bridges_mutex); + for (i = 0; i < ARRAY_SIZE(vexpress_config_bridges); i++) { + struct vexpress_config_bridge *bridge = + &vexpress_config_bridges[i]; + + if (test_bit(i, vexpress_config_bridges_map) && + bridge->node == bridge_node) { + func->bridge = bridge; + func->func = bridge->info->func_get(dev, node); + break; + } + } + mutex_unlock(&vexpress_config_bridges_mutex); + + if (!func->func) { + of_node_put(node); + kfree(func); + return NULL; + } + + return func; +} + +void vexpress_config_func_put(struct vexpress_config_func *func) +{ + func->bridge->info->func_put(func->func); + of_node_put(func->bridge->node); + kfree(func); +} + + +struct vexpress_config_trans { + struct vexpress_config_func *func; + int offset; + bool write; + u32 *data; + int status; + struct completion completion; + struct list_head list; +}; + +static void vexpress_config_dump_trans(const char *what, + struct vexpress_config_trans *trans) +{ + pr_debug("%s %s trans %p func 0x%p offset %d data 0x%x status %d\n", + what, trans->write ? "write" : "read", trans, + trans->func->func, trans->offset, + trans->data ? *trans->data : 0, trans->status); +} + +static int vexpress_config_schedule(struct vexpress_config_trans *trans) +{ + int status; + struct vexpress_config_bridge *bridge = trans->func->bridge; + unsigned long flags; + + init_completion(&trans->completion); + trans->status = -EFAULT; + + spin_lock_irqsave(&bridge->transactions_lock, flags); + + vexpress_config_dump_trans("Executing", trans); + + if (list_empty(&bridge->transactions)) + status = bridge->info->func_exec(trans->func->func, + trans->offset, trans->write, trans->data); + else + status = VEXPRESS_CONFIG_STATUS_WAIT; + + switch (status) { + case VEXPRESS_CONFIG_STATUS_DONE: + vexpress_config_dump_trans("Finished", trans); + trans->status = status; + break; + case VEXPRESS_CONFIG_STATUS_WAIT: + list_add_tail(&trans->list, &bridge->transactions); + break; + } + + spin_unlock_irqrestore(&bridge->transactions_lock, flags); + + return status; +} + +void vexpress_config_complete(struct vexpress_config_bridge *bridge, + int status) +{ + struct vexpress_config_trans *trans; + unsigned long flags; + + spin_lock_irqsave(&bridge->transactions_lock, flags); + + trans = list_first_entry(&bridge->transactions, + struct vexpress_config_trans, list); + vexpress_config_dump_trans("Completed", trans); + + trans->status = status; + list_del(&trans->list); + + if (!list_empty(&bridge->transactions)) { + vexpress_config_dump_trans("Pending", trans); + + bridge->info->func_exec(trans->func->func, trans->offset, + trans->write, trans->data); + } + spin_unlock_irqrestore(&bridge->transactions_lock, flags); + + complete(&trans->completion); +} + +int vexpress_config_wait(struct vexpress_config_trans *trans) +{ + wait_for_completion(&trans->completion); + + return trans->status; +} + + +int vexpress_config_read(struct vexpress_config_func *func, int offset, + u32 *data) +{ + struct vexpress_config_trans trans = { + .func = func, + .offset = offset, + .write = false, + .data = data, + .status = 0, + }; + int status = vexpress_config_schedule(&trans); + + if (status == VEXPRESS_CONFIG_STATUS_WAIT) + status = vexpress_config_wait(&trans); + + return status; +} +EXPORT_SYMBOL(vexpress_config_read); + +int vexpress_config_write(struct vexpress_config_func *func, int offset, + u32 data) +{ + struct vexpress_config_trans trans = { + .func = func, + .offset = offset, + .write = true, + .data = &data, + .status = 0, + }; + int status = vexpress_config_schedule(&trans); + + if (status == VEXPRESS_CONFIG_STATUS_WAIT) + status = vexpress_config_wait(&trans); + + return status; +} +EXPORT_SYMBOL(vexpress_config_write); diff --git a/include/linux/vexpress.h b/include/linux/vexpress.h new file mode 100644 index 000000000000..c2d877a7b691 --- /dev/null +++ b/include/linux/vexpress.h @@ -0,0 +1,85 @@ +/* + * 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 + */ + +#ifndef _LINUX_VEXPRESS_H +#define _LINUX_VEXPRESS_H + +#include <linux/device.h> + +#define VEXPRESS_SITE_MB 0 +#define VEXPRESS_SITE_DB1 1 +#define VEXPRESS_SITE_DB2 2 +#define VEXPRESS_SITE_MASTER 0xf + +#define VEXPRESS_CONFIG_STATUS_DONE 0 +#define VEXPRESS_CONFIG_STATUS_WAIT 1 + +/* Config bridge API */ + +/** + * struct vexpress_config_bridge_info - description of the platform + * configuration infrastructure bridge. + * + * @name: Bridge name + * + * @func_get: Obtains pointer to a configuration function for a given + * device or a Device Tree node, to be used with @func_put + * and @func_exec. The node pointer should take precedence + * over device pointer when both are passed. + * + * @func_put: Tells the bridge that the function will not be used any + * more, so all allocated resources can be released. + * + * @func_exec: Executes a configuration function read or write operation. + * The offset selects a 32 bit word of the value accessed. + * Must return VEXPRESS_CONFIG_STATUS_DONE when operation + * is finished immediately, VEXPRESS_CONFIG_STATUS_WAIT when + * will be completed in some time or negative value in case + * of error. + */ +struct vexpress_config_bridge_info { + const char *name; + void *(*func_get)(struct device *dev, struct device_node *node); + void (*func_put)(void *func); + int (*func_exec)(void *func, int offset, bool write, u32 *data); +}; + +struct vexpress_config_bridge; + +struct vexpress_config_bridge *vexpress_config_bridge_register( + struct device_node *node, + struct vexpress_config_bridge_info *info); +void vexpress_config_bridge_unregister(struct vexpress_config_bridge *bridge); + +void vexpress_config_complete(struct vexpress_config_bridge *bridge, + int status); + +/* Config function API */ + +struct vexpress_config_func; + +struct vexpress_config_func *__vexpress_config_func_get(struct device *dev, + struct device_node *node); +#define vexpress_config_func_get_by_dev(dev) \ + __vexpress_config_func_get(dev, NULL) +#define vexpress_config_func_get_by_node(node) \ + __vexpress_config_func_get(NULL, node) +void vexpress_config_func_put(struct vexpress_config_func *func); + +/* Both may sleep! */ +int vexpress_config_read(struct vexpress_config_func *func, int offset, + u32 *data); +int vexpress_config_write(struct vexpress_config_func *func, int offset, + u32 data); + +#endif |