/*
* Core maple bus functionality
*
* Copyright (C) 2007 Adrian McMenamin
*
* Based on 2.4 code by:
*
* Copyright (C) 2000-2001 YAEGASHI Takeshi
* Copyright (C) 2001 M. R. Brown
* Copyright (C) 2001 Paul Mundt
*
* and others.
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/list.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/maple.h>
#include <linux/dma-mapping.h>
#include <asm/cacheflush.h>
#include <asm/dma.h>
#include <asm/io.h>
#include <asm/mach/dma.h>
#include <asm/mach/sysasic.h>
#include <asm/mach/maple.h>
MODULE_AUTHOR("Yaegshi Takeshi, Paul Mundt, M.R. Brown, Adrian McMenamin");
MODULE_DESCRIPTION("Maple bus driver for Dreamcast");
MODULE_LICENSE("GPL v2");
MODULE_SUPPORTED_DEVICE("{{SEGA, Dreamcast/Maple}}");
static void maple_dma_handler(struct work_struct *work);
static void maple_vblank_handler(struct work_struct *work);
static DECLARE_WORK(maple_dma_process, maple_dma_handler);
static DECLARE_WORK(maple_vblank_process, maple_vblank_handler);
static LIST_HEAD(maple_waitq);
static LIST_HEAD(maple_sentq);
static DEFINE_MUTEX(maple_list_lock);
static struct maple_driver maple_dummy_driver;
static struct device maple_bus;
static int subdevice_map[MAPLE_PORTS];
static unsigned long *maple_sendbuf, *maple_sendptr, *maple_lastptr;
static unsigned long maple_pnp_time;
static int started, scanning, liststatus;
static struct kmem_cache *maple_queue_cache;
struct maple_device_specify {
int port;
int unit;
};
/**
* maple_driver_register - register a device driver
* automatically makes the driver bus a maple bus
* @drv: the driver to be registered
*/
int maple_driver_register(struct device_driver *drv)
{
if (!drv)
return -EINVAL;
drv->bus = &maple_bus_type;
return driver_register(drv);
}
EXPORT_SYMBOL_GPL(maple_driver_register);
/* set hardware registers to enable next round of dma */
static void maplebus_dma_reset(void)
{
ctrl_outl(MAPLE_MAGIC, MAPLE_RESET);
/* set trig type to 0 for software trigger, 1 for hardware (VBLANK) */
ctrl_outl(1, MAPLE_TRIGTYPE);
ctrl_outl(MAPLE_2MBPS | MAPLE_TIMEOUT(50000), MAPLE_SPEED);
ctrl_outl(PHYSADDR(maple_sendbuf), MAPLE_DMAADDR);
ctrl_outl(1, MAPLE_ENABLE);
}
/**
* maple_getcond_callback - setup handling MAPLE_COMMAND_GETCOND
* @dev: device responding
* @callback: handler callback
* @interval: interval in jiffies between callbacks
* @function: the function code for the device
*/
void maple_getcond_callback(struct maple_device *dev,
void (*callback) (struct mapleq * mq),
unsigned long interval, unsigned long function)
{
dev->callback = callback;
dev->interval = interval;
dev->function = cpu_to_be32(function);
dev->when = jiffies;
}
EXPORT_SYMBOL_GPL(maple_getcond_callback);
static int maple_dma_done(void)
{
return (ctrl_inl(MAPLE_STATE) & 1) == 0;
}
static void maple_release_device(struct device *dev)
{
if (dev->type) {
kfree(dev->type->name);
kfree(dev->type);
}
}
/**
* maple_add_packet - add a single instruction to the queue
* @mq: instruction to add to waiting queue
*/
void maple_add_packet(struct mapleq *mq)
{
mutex_lock(&maple_list_lock);
list_add(&mq->list, &maple_waitq);
mutex_unlock(&maple_list_lock);
}
EXPORT_SYMBOL_GPL(maple_add_packet);
static struct mapleq *maple_allocq(struct maple_device *dev)
{
struct mapleq *mq;
mq = kmalloc(sizeof(*mq), GFP_KERNEL);
if (!mq)
return NULL;
mq->dev = dev;
mq->recvbufdcsp = kmem_cache_zalloc(maple_queue_cache, GFP_KERNEL);
mq->recvbuf = (void *) P2SEGADDR(mq->recvbufdcsp);
if (!mq->recvbuf) {
kfree(mq);
return NULL;
}
return mq;
}
static struct maple_device *maple_alloc_dev(int port, int unit)
{
struct maple_device *dev;
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev)
return NULL;
dev->port = port;
dev->unit = unit;
dev->mq = maple_allocq(dev);
if (!dev->mq) {
kfree(dev);
return NULL;
}
return dev;
}
static void maple_free_dev(struct maple_device *mdev)
{
if (!mdev)
return;
if (mdev->mq) {
kmem_cache_free(maple_queue_cache, mdev->mq->recvbufdcsp);
kfree(mdev->mq);
}
kfree(mdev);
}
/* process the command queue into a maple command block
* terminating command has bit 32 of first long set to 0
*/
static void maple_build_block(struct mapleq *mq)
{
int port, unit, from, to, len;
unsigned long *lsendbuf = mq->sendbuf;
port = mq->dev->port & 3;
unit = mq->dev->unit;
len = mq->length;
from = port << 6;
to = (port << 6) | (unit > 0 ? (1 << (unit - 1)) & 0x1f : 0x20);
*maple_lastptr &= 0x7fffffff;
maple_lastptr = maple_sendptr;
*maple_sendptr++ = (port << 16) | len | 0x80000000;
*maple_sendptr++ = PHYSADDR(mq->recvbuf);
*maple_sendptr++ =
mq->command | (to << 8) | (from << 16) | (len << 24);
while (len-- > 0)
*maple_sendptr++ = *lsendbuf++;
}
/* build up command queue */
static void maple_send(void)
{
int i;
int maple_packets;
struct mapleq *mq, *nmq;
if (!list_empty(&maple_sentq))
return;
if (list_empty(&maple_waitq) || !maple_dma_done())
return;
maple_packets = 0;
maple_sendptr = maple_lastptr = maple_sendbuf;
list_for_each_entry_safe(mq, nmq, &maple_waitq, list) {
maple_build_block(mq);
list_move(&mq->list, &maple_sentq);
if (maple_packets++ > MAPLE_MAXPACKETS)
break;
}
if (maple_packets > 0) {
for (i = 0; i < (1 << MAPLE_DMA_PAGES); i++)
dma_cache_sync(0, maple_sendbuf + i * PAGE_SIZE,
PAGE_SIZE, DMA_BIDIRECTIONAL);
}
}
static int attach_matching_maple_driver(struct device_driver *driver,
void *devptr)
{
struct maple_driver *maple_drv;
struct maple_device *mdev;
mdev = devptr;
maple_drv = to_maple_driver(driver);
if (mdev->devinfo.function & be32_to_cpu(maple_drv->function)) {
if (maple_drv->connect(mdev) == 0) {
mdev->driver = maple_drv;
return 1;
}
}
return 0;
}
static void maple_detach_driver(struct maple_device *mdev)
{
if (!mdev)
return;
if (mdev->driver) {
if (mdev->driver->disconnect)
mdev->driver->disconnect(mdev);
}
mdev->driver = NULL;
if (mdev->registered) {
maple_release_device(&mdev->dev);
device_unregister(&mdev->dev);
}
mdev->registered = 0;
maple_free_dev(mdev);
}
/* process initial MAPLE_COMMAND_DEVINFO for each device or port */
static void maple_attach_driver(struct maple_device *dev)
{
char *p;
char *recvbuf;
unsigned long function;
int matched, retval;
recvbuf = dev->mq->recvbuf;
memcpy(&dev->devinfo, recvbuf + 4, sizeof(dev->devinfo));
memcpy(dev->product_name, dev->devinfo.product_name, 30);
memcpy(dev->product_licence, dev->devinfo.product_licence, 60);
dev->product_name[30] = '\0';
dev->product_licence[60] = '\0';
for (p = dev->product_name + 29; dev->product_name <= p; p--)
if (*p == ' ')
*p = '\0';
else
break;
for (p = dev->product_licence + 59; dev->product_licence <= p; p--)
if (*p == ' ')
*p = '\0';
else
break;
function = be32_to_cpu(dev->devinfo.function);
if (function > 0x200) {
/* Do this silently - as not a real device */
function = 0;
dev->driver = &maple_dummy_driver;
sprintf(dev->dev.bus_id, "%d:0.port", dev->port);
} else {
printk(KERN_INFO
"Maple bus at (%d, %d): Connected function 0x%lX\n",
dev->port, dev->unit, function);
matched =
bus_for_each_drv(&maple_bus_type, NULL, dev,
attach_matching_maple_driver);
if (matched == 0) {
/* Driver does not exist yet */
printk(KERN_INFO
"No maple driver found for this device\n");
dev->driver = &maple_dummy_driver;
}
sprintf(dev->dev.bus_id, "%d:0%d.%lX", dev->port,
dev->unit, function);
}
dev->function = function;
dev->dev.bus = &maple_bus_type;
dev->dev.parent = &maple_bus;
dev->dev.release = &maple_release_device;
retval = device_register(&dev->dev);
if (retval) {
printk(KERN_INFO
"Maple bus: Attempt to register device (%x, %x) failed.\n",
dev->port, dev->unit);
maple_free_dev(dev);
}
dev->registered = 1;
}
/*
* if device has been registered for the given
* port and unit then return 1 - allows identification
* of which devices need to be attached or detached
*/
static int detach_maple_device(struct device *device, void *portptr)
{
struct maple_device_specify *ds;
struct maple_device *mdev;
ds = portptr;
mdev = to_maple_dev(device);
if (mdev->port == ds->port && mdev->unit == ds->unit)
return 1;
return 0;
}
static int setup_maple_commands(struct device *device, void *ignored)
{
struct maple_device *maple_dev = to_maple_dev(device);
if ((maple_dev->interval > 0)
&& time_after(jiffies, maple_dev->when)) {
maple_dev->when = jiffies + maple_dev->interval;
maple_dev->mq->command = MAPLE_COMMAND_GETCOND;
maple_dev->mq->sendbuf = &maple_dev->function;
maple_dev->mq->length = 1;
maple_add_packet(maple_dev->mq);
liststatus++;
} else {
if (time_after(jiffies, maple_pnp_time)) {
maple_dev->mq->command = MAPLE_COMMAND_DEVINFO;
maple_dev->mq->length = 0;
maple_add_packet(maple_dev->mq);
liststatus++;
}
}
return 0;
}
/* VBLANK bottom half - implemented via workqueue */
static void maple_vblank_handler(struct work_struct *work)
{
if (!maple_dma_done())
return;
if (!list_empty(&maple_sentq))
return;
ctrl_outl(0, MAPLE_ENABLE);
liststatus = 0;
bus_for_each_dev(&maple_bus_type, NULL, NULL,
setup_maple_commands);
if (time_after(jiffies, maple_pnp_time))
maple_pnp_time = jiffies + MAPLE_PNP_INTERVAL;
if (liststatus && list_empty(&maple_sentq)) {
INIT_LIST_HEAD(&maple_sentq);
maple_send();
}
maplebus_dma_reset();
}
/* handle devices added via hotplugs - placing them on queue for DEVINFO*/
static void maple_map_subunits(struct maple_device *mdev, int submask)
{
int retval, k, devcheck;
struct maple_device *mdev_add;
struct maple_device_specify ds;
for (k = 0; k < 5; k++) {
ds.port = mdev->port;
ds.unit = k + 1;
retval =
bus_for_each_dev(&maple_bus_type, NULL, &ds,
detach_maple_device);
if (retval) {
submask = submask >> 1;
continue;
}
devcheck = submask & 0x01;
if (devcheck) {
mdev_add = maple_alloc_dev(mdev->port, k + 1);
if (!mdev_add)
return;
mdev_add->mq->command = MAPLE_COMMAND_DEVINFO;
mdev_add->mq->length = 0;
maple_add_packet(mdev_add->mq);
scanning = 1;
}
submask = submask >> 1;
}
}
/* mark a device as removed */
static void maple_clean_submap(struct maple_device *mdev)
{
int killbit;
killbit = (mdev->unit > 0 ? (1 << (mdev->unit - 1)) & 0x1f : 0x20);
killbit = ~killbit;
killbit &= 0xFF;
subdevice_map[mdev->port] = subdevice_map[mdev->port] & killbit;
}
/* handle empty port or hotplug removal */
static void maple_response_none(struct maple_device *mdev,
struct mapleq *mq)
{
if (mdev->unit != 0) {
list_del(&mq->list);
maple_clean_submap(mdev);
printk(KERN_INFO
"Maple bus device detaching at (%d, %d)\n",
mdev->port, mdev->unit);
maple_detach_driver(mdev);
return;
}
if (!started) {
printk(KERN_INFO "No maple devices attached to port %d\n",
mdev->port);
return;
}
maple_clean_submap(mdev);
}
/* preprocess hotplugs or scans */
static void maple_response_devinfo(struct maple_device *mdev,
char *recvbuf)
{
char submask;
if ((!started) || (scanning == 2)) {
maple_attach_driver(mdev);
return;
}
if (mdev->unit == 0) {
submask = recvbuf[2] & 0x1F;
if (submask ^ subdevice_map[mdev->port]) {
maple_map_subunits(mdev, submask);
subdevice_map[mdev->port] = submask;
}
}
}
/* maple dma end bottom half - implemented via workqueue */
static void maple_dma_handler(struct work_struct *work)
{
struct mapleq *mq, *nmq;
struct maple_device *dev;
char *recvbuf;
enum maple_code code;
if (!maple_dma_done())
return;
ctrl_outl(0, MAPLE_ENABLE);
if (!list_empty(&maple_sentq)) {
list_for_each_entry_safe(mq, nmq, &maple_sentq, list) {
recvbuf = mq->recvbuf;
code = recvbuf[0];
dev = mq->dev;
switch (code) {
case MAPLE_RESPONSE_NONE:
maple_response_none(dev, mq);
break;
case MAPLE_RESPONSE_DEVINFO:
maple_response_devinfo(dev, recvbuf);
break;
case MAPLE_RESPONSE_DATATRF:
if (dev->callback)
dev->callback(mq);
break;
case MAPLE_RESPONSE_FILEERR:
case MAPLE_RESPONSE_AGAIN:
case MAPLE_RESPONSE_BADCMD:
case MAPLE_RESPONSE_BADFUNC:
printk(KERN_DEBUG
"Maple non-fatal error 0x%X\n",
code);
break;
case MAPLE_RESPONSE_ALLINFO:
printk(KERN_DEBUG
"Maple - extended device information not supported\n");
break;
case MAPLE_RESPONSE_OK:
break;
default:
break;
}
}
INIT_LIST_HEAD(&maple_sentq);
if (scanning == 1) {
maple_send();
scanning = 2;
} else
scanning = 0;
if (started == 0)
started = 1;
}
maplebus_dma_reset();
}
static irqreturn_t maplebus_dma_interrupt(int irq, void *dev_id)
{
/* Load everything into the bottom half */
schedule_work(&maple_dma_process);
return IRQ_HANDLED;
}
static irqreturn_t maplebus_vblank_interrupt(int irq, void *dev_id)
{
schedule_work(&maple_vblank_process);
return IRQ_HANDLED;
}
static struct irqaction maple_dma_irq = {
.name = "maple bus DMA handler",
.handler = maplebus_dma_interrupt,
.flags = IRQF_SHARED,
};
static struct irqaction maple_vblank_irq = {
.name = "maple bus VBLANK handler",
.handler = maplebus_vblank_interrupt,
.flags = IRQF_SHARED,
};
static int maple_set_dma_interrupt_handler(void)
{
return setup_irq(HW_EVENT_MAPLE_DMA, &maple_dma_irq);
}
static int maple_set_vblank_interrupt_handler(void)
{
return setup_irq(HW_EVENT_VSYNC, &maple_vblank_irq);
}
static int maple_get_dma_buffer(void)
{
maple_sendbuf =
(void *) __get_free_pages(GFP_KERNEL | __GFP_ZERO,
MAPLE_DMA_PAGES);
if (!maple_sendbuf)
return -ENOMEM;
return 0;
}
static int match_maple_bus_driver(struct device *devptr,
struct device_driver *drvptr)
{
struct maple_driver *maple_drv;
struct maple_device *maple_dev;
maple_drv = container_of(drvptr, struct maple_driver, drv);
maple_dev = container_of(devptr, struct maple_device, dev);
/* Trap empty port case */
if (maple_dev->devinfo.function == 0xFFFFFFFF)
return 0;
else if (maple_dev->devinfo.function &
be32_to_cpu(maple_drv->function))
return 1;
return 0;
}
static int maple_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
{
return 0;
}
static void maple_bus_release(struct device *dev)
{
}
static struct maple_driver maple_dummy_driver = {
.drv = {
.name = "maple_dummy_driver",
.bus = &maple_bus_type,
},
};
struct bus_type maple_bus_type = {
.name = "maple",
.match = match_maple_bus_driver,
.uevent = maple_bus_uevent,
};
EXPORT_SYMBOL_GPL(maple_bus_type);
static struct device maple_bus = {
.bus_id = "maple",
.release = maple_bus_release,
};
static int __init maple_bus_init(void)
{
int retval, i;
struct maple_device *mdev[MAPLE_PORTS];
ctrl_outl(0, MAPLE_STATE);
retval = device_register(&maple_bus);
if (retval)
goto cleanup;
retval = bus_register(&maple_bus_type);
if (retval)
goto cleanup_device;
retval = driver_register(&maple_dummy_driver.drv);
if (retval)
goto cleanup_bus;
/* allocate memory for maple bus dma */
retval = maple_get_dma_buffer();
if (retval) {
printk(KERN_INFO
"Maple bus: Failed to allocate Maple DMA buffers\n");
goto cleanup_basic;
}
/* set up DMA interrupt handler */
retval = maple_set_dma_interrupt_handler();
if (retval) {
printk(KERN_INFO
"Maple bus: Failed to grab maple DMA IRQ\n");
goto cleanup_dma;
}
/* set up VBLANK interrupt handler */
retval = maple_set_vblank_interrupt_handler();
if (retval) {
printk(KERN_INFO "Maple bus: Failed to grab VBLANK IRQ\n");
goto cleanup_irq;
}
maple_queue_cache =
kmem_cache_create("maple_queue_cache", 0x400, 0,
SLAB_HWCACHE_ALIGN, NULL);
if (!maple_queue_cache)
goto cleanup_bothirqs;
/* setup maple ports */
for (i = 0; i < MAPLE_PORTS; i++) {
mdev[i] = maple_alloc_dev(i, 0);
if (!mdev[i]) {
while (i-- > 0)
maple_free_dev(mdev[i]);
goto cleanup_cache;
}
mdev[i]->registered = 0;
mdev[i]->mq->command = MAPLE_COMMAND_DEVINFO;
mdev[i]->mq->length = 0;
maple_attach_driver(mdev[i]);
maple_add_packet(mdev[i]->mq);
subdevice_map[i] = 0;
}
/* setup maplebus hardware */
maplebus_dma_reset();
/* initial detection */
maple_send();
maple_pnp_time = jiffies;
printk(KERN_INFO "Maple bus core now registered.\n");
return 0;
cleanup_cache:
kmem_cache_destroy(maple_queue_cache);
cleanup_bothirqs:
free_irq(HW_EVENT_VSYNC, 0);
cleanup_irq:
free_irq(HW_EVENT_MAPLE_DMA, 0);
cleanup_dma:
free_pages((unsigned long) maple_sendbuf, MAPLE_DMA_PAGES);
cleanup_basic:
driver_unregister(&maple_dummy_driver.drv);
cleanup_bus:
bus_unregister(&maple_bus_type);
cleanup_device:
device_unregister(&maple_bus);
cleanup:
printk(KERN_INFO "Maple bus registration failed\n");
return retval;
}
subsys_initcall(maple_bus_init);
