/*
* ocp.c
*
* (c) Benjamin Herrenschmidt (benh@kernel.crashing.org)
* Mipsys - France
*
* Derived from work (c) Armin Kuster akuster@pacbell.net
*
* Additional support and port to 2.6 LDM/sysfs by
* Matt Porter <mporter@kernel.crashing.org>
* Copyright 2004 MontaVista Software, Inc.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* OCP (On Chip Peripheral) is a software emulated "bus" with a
* pseudo discovery method for dumb peripherals. Usually these type
* of peripherals are found on embedded SoC (System On a Chip)
* processors or highly integrated system controllers that have
* a host bridge and many peripherals. Common examples where
* this is already used include the PPC4xx, PPC85xx, MPC52xx,
* and MV64xxx parts.
*
* This subsystem creates a standard OCP bus type within the
* device model. The devices on the OCP bus are seeded by an
* an initial OCP device array created by the arch-specific
* Device entries can be added/removed/modified through OCP
* helper functions to accommodate system and board-specific
* parameters commonly found in embedded systems. OCP also
* provides a standard method for devices to describe extended
* attributes about themselves to the system. A standard access
* method allows OCP drivers to obtain the information, both
* SoC-specific and system/board-specific, needed for operation.
*/
#include <linux/module.h>
#include <linux/list.h>
#include <linux/miscdevice.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/pm.h>
#include <linux/bootmem.h>
#include <linux/device.h>
#include <linux/rwsem.h>
#include <asm/io.h>
#include <asm/ocp.h>
#include <asm/errno.h>
#include <asm/semaphore.h>
//#define DBG(x) printk x
#define DBG(x)
extern int mem_init_done;
extern struct ocp_def core_ocp[]; /* Static list of devices, provided by
CPU core */
LIST_HEAD(ocp_devices); /* List of all OCP devices */
DECLARE_RWSEM(ocp_devices_sem); /* Global semaphores for those lists */
static int ocp_inited;
/* Sysfs support */
#define OCP_DEF_ATTR(field, format_string) \
static ssize_t \
show_##field(struct device *dev, struct device_attribute *attr, char *buf) \
{ \
struct ocp_device *odev = to_ocp_dev(dev); \
\
return sprintf(buf, format_string, odev->def->field); \
} \
static DEVICE_ATTR(field, S_IRUGO, show_##field, NULL);
OCP_DEF_ATTR(vendor, "0x%04x\n");
OCP_DEF_ATTR(function, "0x%04x\n");
OCP_DEF_ATTR(index, "0x%04x\n");
#ifdef CONFIG_PTE_64BIT
OCP_DEF_ATTR(paddr, "0x%016Lx\n");
#else
OCP_DEF_ATTR(paddr, "0x%08lx\n");
#endif
OCP_DEF_ATTR(irq, "%d\n");
OCP_DEF_ATTR(pm, "%lu\n");
void ocp_create_sysfs_dev_files(struct ocp_device *odev)
{
struct device *dev = &odev->dev;
/* Current OCP device def attributes */
device_create_file(dev, &dev_attr_vendor);
device_create_file(dev, &dev_attr_function);
device_create_file(dev, &dev_attr_index);
device_create_file(dev, &dev_attr_paddr);
device_create_file(dev, &dev_attr_irq);
device_create_file(dev, &dev_attr_pm);
/* Current OCP device additions attributes */
if (odev->def->additions && odev->def->show)
odev->def->show(dev);
}
/**
* ocp_device_match - Match one driver to one device
* @drv: driver to match
* @dev: device to match
*
* This function returns 0 if the driver and device don't match
*/
static int
ocp_device_match(struct device *dev, struct device_driver *drv)
{
struct ocp_device *ocp_dev = to_ocp_dev(dev);
struct ocp_driver *ocp_drv = to_ocp_drv(drv);
const struct ocp_device_id *ids = ocp_drv->id_table;
if (!ids)
return 0;
while (ids->vendor || ids->function) {
if ((ids->vendor == OCP_ANY_ID
|| ids->vendor == ocp_dev->def->vendor)
&& (ids->function == OCP_ANY_ID
|| ids->function == ocp_dev->def->function))
return 1;
ids++;
}
return 0;
}
static int
ocp_device_probe(struct device *dev)
{
int error = 0;
struct ocp_driver *drv;
struct ocp_device *ocp_dev;
drv = to_ocp_drv(dev->driver);
ocp_dev = to_ocp_dev(dev);
if (drv->probe) {
error = drv->probe(ocp_dev);
if (error >= 0) {
ocp_dev->driver = drv;
error = 0;
}
}
return error;
}
static int
ocp_device_remove(struct device *dev)
{
struct ocp_device *ocp_dev = to_ocp_dev(dev);
if (ocp_dev->driver) {
if (ocp_dev->driver->remove)
ocp_dev->driver->remove(ocp_dev);
ocp_dev->driver = NULL;
}
return 0;
}
static int
ocp_device_suspend(struct device *dev, pm_message_t state)
{
struct ocp_device *ocp_dev = to_ocp_dev(dev);
struct ocp_driver *ocp_drv = to_ocp_drv(dev->driver);
if (dev->driver && ocp_drv->suspend)
return ocp_drv->suspend(ocp_dev, state);
return 0;
}
static int
ocp_device_resume(struct device *dev)
{
struct ocp_device *ocp_dev = to_ocp_dev(dev);
struct ocp_driver *ocp_drv = to_ocp_drv(dev->driver);
if (dev->driver && ocp_drv->resume)
return ocp_drv->resume(ocp_dev);
return 0;
}
struct bus_type ocp_bus_type = {
.name = "ocp",
.match = ocp_device_match,
.probe = ocp_device_probe,
.remove = ocp_device_remove,
.suspend = ocp_device_suspend,
.resume = ocp_device_resume,
};
/**
* ocp_register_driver - Register an OCP driver
* @drv: pointer to statically defined ocp_driver structure
*
* The driver's probe() callback is called either recursively
* by this function or upon later call of ocp_driver_init
*
* NOTE: Detection of devices is a 2 pass step on this implementation,
* hotswap isn't supported. First, all OCP devices are put in the device
* list, _then_ all drivers are probed on each match.
*/
int
ocp_register_driver(struct ocp_driver *drv)
{
/* initialize common driver fields */
drv->driver.name = drv->name;
drv->driver.bus = &ocp_bus_type;
/* register with core */
return driver_register(&drv->driver);
}
/**
* ocp_unregister_driver - Unregister an OCP driver
* @drv: pointer to statically defined ocp_driver structure
*
* The driver's remove() callback is called recursively
* by this function for any device already registered
*/
void
ocp_unregister_driver(struct ocp_driver *drv)
{
DBG(("ocp: ocp_unregister_driver(%s)...\n", drv->name));
driver_unregister(&drv->driver);
DBG(("ocp: ocp_unregister_driver(%s)... done.\n", drv->name));
}
/* Core of ocp_find_device(). Caller must hold ocp_devices_sem */
static struct ocp_device *
__ocp_find_device(unsigned int vendor, unsigned int function, int index)
{
struct list_head *entry;
struct ocp_device *dev, *found = NULL;
DBG(("ocp: __ocp_find_device(vendor: %x, function: %x, index: %d)...\n", vendor, function, index));
list_for_each(entry, &ocp_devices) {
dev = list_entry(entry, struct ocp_device, link);
if (vendor != OCP_ANY_ID && vendor != dev->def->vendor)
continue;
if (function != OCP_ANY_ID && function != dev->def->function)
continue;
if (index != OCP_ANY_INDEX && index != dev->def->index)
continue;
found = dev;
break;
}
DBG(("ocp: __ocp_find_device(vendor: %x, function: %x, index: %d)... done\n", vendor, function, index));
return found;
}
/**
* ocp_find_device - Find a device by function & index
* @vendor: vendor ID of the device (or OCP_ANY_ID)
* @function: function code of the device (or OCP_ANY_ID)
* @idx: index of the device (or OCP_ANY_INDEX)
*
* This function allows a lookup of a given function by it's
* index, it's typically used to find the MAL or ZMII associated
* with an EMAC or similar horrors.
* You can pass vendor, though you usually want OCP_ANY_ID there...
*/
struct ocp_device *
ocp_find_device(unsigned int vendor, unsigned int function, int index)
{
struct ocp_device *dev;
down_read(&ocp_devices_sem);
dev = __ocp_find_device(vendor, function, index);
up_read(&ocp_devices_sem);
return dev;
}
/**
* ocp_get_one_device - Find a def by function & index
* @vendor: vendor ID of the device (or OCP_ANY_ID)
* @function: function code of the device (or OCP_ANY_ID)
* @idx: index of the device (or OCP_ANY_INDEX)
*
* This function allows a lookup of a given ocp_def by it's
* vendor, function, and index. The main purpose for is to
* allow modification of the def before binding to the driver
*/
struct ocp_def *
ocp_get_one_device(unsigned int vendor, unsigned int function, int index)
{
struct ocp_device *dev;
struct ocp_def *found = NULL;
DBG(("ocp: ocp_get_one_device(vendor: %x, function: %x, index: %d)...\n",
vendor, function, index));
dev = ocp_find_device(vendor, function, index);
if (dev)
found = dev->def;
DBG(("ocp: ocp_get_one_device(vendor: %x, function: %x, index: %d)... done.\n",
vendor, function, index));
return found;
}
/**
* ocp_add_one_device - Add a device
* @def: static device definition structure
*
* This function adds a device definition to the
* device list. It may only be called before
* ocp_driver_init() and will return an error
* otherwise.
*/
int
ocp_add_one_device(struct ocp_def *def)
{
struct ocp_device *dev;
DBG(("ocp: ocp_add_one_device()...\n"));
/* Can't be called after ocp driver init */
if (ocp_inited)
return 1;
if (mem_init_done)
dev = kmalloc(sizeof(*dev), GFP_KERNEL);
else
dev = alloc_bootmem(sizeof(*dev));
if (dev == NULL)
return 1;
memset(dev, 0, sizeof(*dev));
dev->def = def;
dev->current_state = 4;
sprintf(dev->name, "OCP device %04x:%04x:%04x",
dev->def->vendor, dev->def->function, dev->def->index);
down_write(&ocp_devices_sem);
list_add_tail(&dev->link, &ocp_devices);
up_write(&ocp_devices_sem);
DBG(("ocp: ocp_add_one_device()...done\n"));
return 0;
}
/**
* ocp_remove_one_device - Remove a device by function & index
* @vendor: vendor ID of the device (or OCP_ANY_ID)
* @function: function code of the device (or OCP_ANY_ID)
* @idx: index of the device (or OCP_ANY_INDEX)
*
* This function allows removal of a given function by its
* index. It may only be called before ocp_driver_init()
* and will return an error otherwise.
*/
int
ocp_remove_one_device(unsigned int vendor, unsigned int function, int index)
{
struct ocp_device *dev;
DBG(("ocp: ocp_remove_one_device(vendor: %x, function: %x, index: %d)...\n", vendor, function, index));
/* Can't be called after ocp driver init */
if (ocp_inited)
return 1;
down_write(&ocp_devices_sem);
dev = __ocp_find_device(vendor, function, index);
list_del(&dev->link);
up_write(&ocp_devices_sem);
DBG(("ocp: ocp_remove_one_device(vendor: %x, function: %x, index: %d)... done.\n", vendor, function, index));
return 0;
}
/**
* ocp_for_each_device - Iterate over OCP devices
* @callback: routine to execute for each ocp device.
* @arg: user data to be passed to callback routine.
*
* This routine holds the ocp_device semaphore, so the
* callback routine cannot modify the ocp_device list.
*/
void
ocp_for_each_device(void(*callback)(struct ocp_device *, void *arg), void *arg)
{
struct list_head *entry;
if (callback) {
down_read(&ocp_devices_sem);
list_for_each(entry, &ocp_devices)
callback(list_entry(entry, struct ocp_device, link),
arg);
up_read(&ocp_devices_sem);
}
}
/**
* ocp_early_init - Init OCP device management
*
* This function builds the list of devices before setup_arch.
* This allows platform code to modify the device lists before
* they are bound to drivers (changes to paddr, removing devices
* etc)
*/
int __init
ocp_early_init(void)
{
struct ocp_def *def;
DBG(("ocp: ocp_early_init()...\n"));
/* Fill the devices list */
for (def = core_ocp; def->vendor != OCP_VENDOR_INVALID; def++)
ocp_add_one_device(def);
DBG(("ocp: ocp_early_init()... done.\n"));
return 0;
}
/**
* ocp_driver_init - Init OCP device management
*
* This function is meant to be called via OCP bus registration.
*/
static int __init
ocp_driver_init(void)
{
int ret = 0, index = 0;
struct device *ocp_bus;
struct list_head *entry;
struct ocp_device *dev;
if (ocp_inited)
return ret;
ocp_inited = 1;
DBG(("ocp: ocp_driver_init()...\n"));
/* Allocate/register primary OCP bus */
ocp_bus = kzalloc(sizeof(struct device), GFP_KERNEL);
if (ocp_bus == NULL)
return 1;
strcpy(ocp_bus->bus_id, "ocp");
bus_register(&ocp_bus_type);
device_register(ocp_bus);
/* Put each OCP device into global device list */
list_for_each(entry, &ocp_devices) {
dev = list_entry(entry, struct ocp_device, link);
sprintf(dev->dev.bus_id, "%2.2x", index);
dev->dev.parent = ocp_bus;
dev->dev.bus = &ocp_bus_type;
device_register(&dev->dev);
ocp_create_sysfs_dev_files(dev);
index++;
}
DBG(("ocp: ocp_driver_init()... done.\n"));
return 0;
}
postcore_initcall(ocp_driver_init);
EXPORT_SYMBOL(ocp_bus_type);
EXPORT_SYMBOL(ocp_find_device);
EXPORT_SYMBOL(ocp_register_driver);
EXPORT_SYMBOL(ocp_unregister_driver);
