/* * Core maple bus functionality * * Copyright (C) 2007 - 2009 Adrian McMenamin * Copyright (C) 2001 - 2008 Paul Mundt * Copyright (C) 2000 - 2001 YAEGASHI Takeshi * Copyright (C) 2001 M. R. Brown * * 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include MODULE_AUTHOR("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); /* mutex to protect queue of waiting packets */ static DEFINE_MUTEX(maple_wlist_lock); static struct maple_driver maple_unsupported_device; 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, fullscan; static struct kmem_cache *maple_queue_cache; struct maple_device_specify { int port; int unit; }; static bool checked[MAPLE_PORTS]; static bool empty[MAPLE_PORTS]; static struct maple_device *baseunits[MAPLE_PORTS]; /** * maple_driver_register - register a maple driver * @drv: maple driver to be registered. * * Registers the passed in @drv, while updating the bus type. * Devices with matching function IDs will be automatically probed. */ int maple_driver_register(struct maple_driver *drv) { if (!drv) return -EINVAL; drv->drv.bus = &maple_bus_type; return driver_register(&drv->drv); } EXPORT_SYMBOL_GPL(maple_driver_register); /** * maple_driver_unregister - unregister a maple driver. * @drv: maple driver to unregister. * * Cleans up after maple_driver_register(). To be invoked in the exit * path of any module drivers. */ void maple_driver_unregister(struct maple_driver *drv) { driver_unregister(&drv->drv); } EXPORT_SYMBOL_GPL(maple_driver_unregister); /* set hardware registers to enable next round of dma */ static void maple_dma_reset(void) { __raw_writel(MAPLE_MAGIC, MAPLE_RESET); /* set trig type to 0 for software trigger, 1 for hardware (VBLANK) */ __raw_writel(1, MAPLE_TRIGTYPE); /* * Maple system register * bits 31 - 16 timeout in units of 20nsec * bit 12 hard trigger - set 0 to keep responding to VBLANK * bits 9 - 8 set 00 for 2 Mbps, 01 for 1 Mbps * bits 3 - 0 delay (in 1.3ms) between VBLANK and start of DMA * max delay is 11 */ __raw_writel(MAPLE_2MBPS | MAPLE_TIMEOUT(0xFFFF), MAPLE_SPEED); __raw_writel(virt_to_phys(maple_sendbuf), MAPLE_DMAADDR); __raw_writel(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 (__raw_readl(MAPLE_STATE) & 1) == 0; } static void maple_release_device(struct device *dev) { struct maple_device *mdev; struct mapleq *mq; mdev = to_maple_dev(dev); mq = mdev->mq; kmem_cache_free(maple_queue_cache, mq->recvbuf); kfree(mq); kfree(mdev); } /** * maple_add_packet - add a single instruction to the maple bus queue * @mdev: maple device * @function: function on device being queried * @command: maple command to add * @length: length of command string (in 32 bit words) * @data: remainder of command string */ int maple_add_packet(struct maple_device *mdev, u32 function, u32 command, size_t length, void *data) { int ret = 0; void *sendbuf = NULL; if (length) { sendbuf = kzalloc(length * 4, GFP_KERNEL); if (!sendbuf) { ret = -ENOMEM; goto out; } ((__be32 *)sendbuf)[0] = cpu_to_be32(function); } mdev->mq->command = command; mdev->mq->length = length; if (length > 1) memcpy(sendbuf + 4, data, (length - 1) * 4); mdev->mq->sendbuf = sendbuf; mutex_lock(&maple_wlist_lock); list_add_tail(&mdev->mq->list, &maple_waitq); mutex_unlock(&maple_wlist_lock); out: return ret; } EXPORT_SYMBOL_GPL(maple_add_packet); static struct mapleq *maple_allocq(struct maple_device *mdev) { struct mapleq *mq; mq = kzalloc(sizeof(*mq), GFP_KERNEL); if (!mq) goto failed_nomem; INIT_LIST_HEAD(&mq->list); mq->dev = mdev; mq->recvbuf = kmem_cache_zalloc(maple_queue_cache, GFP_KERNEL); if (!mq->recvbuf) goto failed_p2; mq->recvbuf->buf = &((mq->recvbuf->bufx)[0]); return mq; failed_p2: kfree(mq); failed_nomem: dev_err(&mdev->dev, "could not allocate memory for device (%d, %d)\n", mdev->port, mdev->unit); return NULL; } static struct maple_device *maple_alloc_dev(int port, int unit) { struct maple_device *mdev; /* zero this out to avoid kobj subsystem * thinking it has already been registered */ mdev = kzalloc(sizeof(*mdev), GFP_KERNEL); if (!mdev) return NULL; mdev->port = port; mdev->unit = unit; mdev->mq = maple_allocq(mdev); if (!mdev->mq) { kfree(mdev); return NULL; } mdev->dev.bus = &maple_bus_type; mdev->dev.parent = &maple_bus; init_waitqueue_head(&mdev->maple_wait); return mdev; } static void maple_free_dev(struct maple_device *mdev) { kmem_cache_free(maple_queue_cache, mdev->mq->recvbuf); 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++ = virt_to_phys(mq->recvbuf->buf); *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, maple_packets = 0; struct mapleq *mq, *nmq; if (!maple_dma_done()) return; /* disable DMA */ __raw_writel(0, MAPLE_ENABLE); if (!list_empty(&maple_sentq)) goto finish; mutex_lock(&maple_wlist_lock); if (list_empty(&maple_waitq)) { mutex_unlock(&maple_wlist_lock); goto finish; } maple_lastptr = maple_sendbuf; maple_sendptr = maple_sendbuf; list_for_each_entry_safe(mq, nmq, &maple_waitq, list) { maple_build_block(mq); list_del_init(&mq->list); list_add_tail(&mq->list, &maple_sentq); if (maple_packets++ > MAPLE_MAXPACKETS) break; } mutex_unlock(&maple_wlist_lock); 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); } finish: maple_dma_reset(); } /* check if there is a driver registered likely to match this device */ static int maple_check_matching_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 & cpu_to_be32(maple_drv->function)) return 1; return 0; } static void maple_detach_driver(struct maple_device *mdev) { device_unregister(&mdev->dev); } /* process initial MAPLE_COMMAND_DEVINFO for each device or port */ static void maple_attach_driver(struct maple_device *mdev) { char *p, *recvbuf; unsigned long function; int matched, error; recvbuf = mdev->mq->recvbuf->buf; /* copy the data as individual elements in * case of memory optimisation */ memcpy(&mdev->devinfo.function, recvbuf + 4, 4); memcpy(&mdev->devinfo.function_data[0], recvbuf + 8, 12); memcpy(&mdev->devinfo.area_code, recvbuf + 20, 1); memcpy(&mdev->devinfo.connector_direction, recvbuf + 21, 1); memcpy(&mdev->devinfo.product_name[0], recvbuf + 22, 30); memcpy(&mdev->devinfo.standby_power, recvbuf + 112, 2); memcpy(&mdev->devinfo.max_power, recvbuf + 114, 2); memcpy(mdev->product_name, mdev->devinfo.product_name, 30); mdev->product_name[30] = '\0'; memcpy(mdev->product_licence, mdev->devinfo.product_licence, 60); mdev->product_licence[60] = '\0'; for (p = mdev->product_name + 29; mdev->product_name <= p; p--) if (*p == ' ') *p = '\0'; else break; for (p = mdev->product_licence + 59; mdev->product_licence <= p; p--) if (*p == ' ') *p = '\0'; else break; function = be32_to_cpu(mdev->devinfo.function); dev_info(&mdev->dev, "detected %s: function 0x%lX: at (%d, %d)\n", mdev->product_name, function, mdev->port, mdev->unit); if (function > 0x200) { /* Do this silently - as not a real device */ function = 0; mdev->driver = &maple_unsupported_device; dev_set_name(&mdev->dev, "%d:0.port", mdev->port); } else { matched = bus_for_each_drv(&maple_bus_type, NULL, mdev, maple_check_matching_driver); if (matched == 0) { /* Driver does not exist yet */ dev_info(&mdev->dev, "no driver found\n"); mdev->driver = &maple_unsupported_device; } dev_set_name(&mdev->dev, "%d:0%d.%lX", mdev->port, mdev->unit, function); } mdev->function = function; mdev->dev.release = &maple_release_device; atomic_set(&mdev->busy, 0); error = device_register(&mdev->dev); if (error) { dev_warn(&mdev->dev, "could not register device at" " (%d, %d), with error 0x%X\n", mdev->unit, mdev->port, error); maple_free_dev(mdev); mdev = NULL; return; } } /* * 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 check_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) { int add; struct maple_device *mdev = to_maple_dev(device); if (mdev->interval > 0 && atomic_read(&mdev->busy) == 0 && time_after(jiffies, mdev->when)) { /* bounce if we cannot add */ add = maple_add_packet(mdev, be32_to_cpu(mdev->devinfo.function), MAPLE_COMMAND_GETCOND, 1, NULL); if (!add) mdev->when = jiffies + mdev->interval; } else { if (time_after(jiffies, maple_pnp_time)) /* Ensure we don't have block reads and devinfo * calls interfering with one another - so flag the * device as busy */ if (atomic_read(&mdev->busy) == 0) { atomic_set(&mdev->busy, 1); maple_add_packet(mdev, 0, MAPLE_COMMAND_DEVINFO, 0, NULL); } } return 0; } /* VBLANK bottom half - implemented via workqueue */ static void maple_vblank_handler(struct work_struct *work) { int x, locking; struct maple_device *mdev; if (!maple_dma_done()) return; __raw_writel(0, MAPLE_ENABLE); if (!list_empty(&maple_sentq)) goto finish; /* * Set up essential commands - to fetch data and * check devices are still present */ bus_for_each_dev(&maple_bus_type, NULL, NULL, setup_maple_commands); if (time_after(jiffies, maple_pnp_time)) { /* * Scan the empty ports - bus is flakey and may have * mis-reported emptyness */ for (x = 0; x < MAPLE_PORTS; x++) { if (checked[x] && empty[x]) { mdev = baseunits[x]; if (!mdev) break; atomic_set(&mdev->busy, 1); locking = maple_add_packet(mdev, 0, MAPLE_COMMAND_DEVINFO, 0, NULL); if (!locking) break; } } maple_pnp_time = jiffies + MAPLE_PNP_INTERVAL; } finish: maple_send(); } /* 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; ds.port = mdev->port; for (k = 0; k < 5; k++) { ds.unit = k + 1; retval = bus_for_each_dev(&maple_bus_type, NULL, &ds, check_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; atomic_set(&mdev_add->busy, 1); maple_add_packet(mdev_add, 0, MAPLE_COMMAND_DEVINFO, 0, NULL); /* mark that we are checking sub devices */ 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) { maple_clean_submap(mdev); if (likely(mdev->unit != 0)) { /* * Block devices play up * and give the impression they have * been removed even when still in place or * trip the mtd layer when they have * really gone - this code traps that eventuality * and ensures we aren't overloaded with useless * error messages */ if (mdev->can_unload) { if (!mdev->can_unload(mdev)) { atomic_set(&mdev->busy, 2); wake_up(&mdev->maple_wait); return; } } dev_info(&mdev->dev, "detaching device at (%d, %d)\n", mdev->port, mdev->unit); maple_detach_driver(mdev); return; } else { if (!started || !fullscan) { if (checked[mdev->port] == false) { checked[mdev->port] = true; empty[mdev->port] = true; dev_info(&mdev->dev, "no devices" " to port %d\n", mdev->port); } return; } } /* Some hardware devices generate false detach messages on unit 0 */ atomic_set(&mdev->busy, 0); } /* preprocess hotplugs or scans */ static void maple_response_devinfo(struct maple_device *mdev, char *recvbuf) { char submask; if (!started || (scanning == 2) || !fullscan) { if ((mdev->unit == 0) && (checked[mdev->port] == false)) { checked[mdev->port] = true; maple_attach_driver(mdev); } else { if (mdev->unit != 0) maple_attach_driver(mdev); if (mdev->unit == 0) { empty[mdev->port] = false; maple_attach_driver(mdev); } } } if (mdev->unit == 0) { submask = recvbuf[2] & 0x1F; if (submask ^ subdevice_map[mdev->port]) { maple_map_subunits(mdev, submask); subdevice_map[mdev->port] = submask; } } } static void maple_response_fileerr(struct maple_device *mdev, void *recvbuf) { if (mdev->fileerr_handler) { mdev->fileerr_handler(mdev, recvbuf); return; } else dev_warn(&mdev->dev, "device at (%d, %d) reports" "file error 0x%X\n", mdev->port, mdev->unit, ((int *)recvbuf)[1]); } static void maple_port_rescan(void) { int i; struct maple_device *mdev; fullscan = 1; for (i = 0; i < MAPLE_PORTS; i++) { if (checked[i] == false) { fullscan = 0; mdev = baseunits[i]; maple_add_packet(mdev, 0, MAPLE_COMMAND_DEVINFO, 0, NULL); } } } /* maple dma end bottom half - implemented via workqueue */ static void maple_dma_handler(struct work_struct *work) { struct mapleq *mq, *nmq; struct maple_device *mdev; char *recvbuf; enum maple_code code; if (!maple_dma_done()) return; __raw_writel(0, MAPLE_ENABLE); if (!list_empty(&maple_sentq)) { list_for_each_entry_safe(mq, nmq, &maple_sentq, list) { mdev = mq->dev; recvbuf = mq->recvbuf->buf; dma_cache_sync(&mdev->dev, recvbuf, 0x400, DMA_FROM_DEVICE); code = recvbuf[0]; kfree(mq->sendbuf); list_del_init(&mq->list); switch (code) { case MAPLE_RESPONSE_NONE: maple_response_none(mdev); break; case MAPLE_RESPONSE_DEVINFO: maple_response_devinfo(mdev, recvbuf); atomic_set(&mdev->busy, 0); break; case MAPLE_RESPONSE_DATATRF: if (mdev->callback) mdev->callback(mq); atomic_set(&mdev->busy, 0); wake_up(&mdev->maple_wait); break; case MAPLE_RESPONSE_FILEERR: maple_response_fileerr(mdev, recvbuf); atomic_set(&mdev->busy, 0); wake_up(&mdev->maple_wait); break; case MAPLE_RESPONSE_AGAIN: case MAPLE_RESPONSE_BADCMD: case MAPLE_RESPONSE_BADFUNC: dev_warn(&mdev->dev, "non-fatal error" " 0x%X at (%d, %d)\n", code, mdev->port, mdev->unit); atomic_set(&mdev->busy, 0); break; case MAPLE_RESPONSE_ALLINFO: dev_notice(&mdev->dev, "extended" " device information request for (%d, %d)" " but call is not supported\n", mdev->port, mdev->unit); atomic_set(&mdev->busy, 0); break; case MAPLE_RESPONSE_OK: atomic_set(&mdev->busy, 0); wake_up(&mdev->maple_wait); break; default: break; } } /* if scanning is 1 then we have subdevices to check */ if (scanning == 1) { maple_send(); scanning = 2; } else scanning = 0; /*check if we have actually tested all ports yet */ if (!fullscan) maple_port_rescan(); /* mark that we have been through the first scan */ started = 1; } maple_send(); } static irqreturn_t maple_dma_interrupt(int irq, void *dev_id) { /* Load everything into the bottom half */ schedule_work(&maple_dma_process); return IRQ_HANDLED; } static irqreturn_t maple_vblank_interrupt(int irq, void *dev_id) { schedule_work(&maple_vblank_process); return IRQ_HANDLED; } static int maple_set_dma_interrupt_handler(void) { return request_irq(HW_EVENT_MAPLE_DMA, maple_dma_interrupt, IRQF_SHARED, "maple bus DMA", &maple_unsupported_device); } static int maple_set_vblank_interrupt_handler(void) { return request_irq(HW_EVENT_VSYNC, maple_vblank_interrupt, IRQF_SHARED, "maple bus VBLANK", &maple_unsupported_device); } 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 maple_match_bus_driver(struct device *devptr, struct device_driver *drvptr) { struct maple_driver *maple_drv = to_maple_driver(drvptr); struct maple_device *maple_dev = to_maple_dev(devptr); /* Trap empty port case */ if (maple_dev->devinfo.function == 0xFFFFFFFF) return 0; else if (maple_dev->devinfo.function & cpu_to_be32(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_unsupported_device = { .drv = { .name = "maple_unsupported_device", .bus = &maple_bus_type, }, }; /* * maple_bus_type - core maple bus structure */ struct bus_type maple_bus_type = { .name = "maple", .match = maple_match_bus_driver, .uevent = maple_bus_uevent, }; EXPORT_SYMBOL_GPL(maple_bus_type); static struct device maple_bus = { .init_name = "maple", .release = maple_bus_release, }; static int __init maple_bus_init(void) { int retval, i; struct maple_device *mdev[MAPLE_PORTS]; __raw_writel(0, MAPLE_ENABLE); retval = device_register(&maple_bus); if (retval) goto cleanup; retval = bus_register(&maple_bus_type); if (retval) goto cleanup_device; retval = driver_register(&maple_unsupported_device.drv); if (retval) goto cleanup_bus; /* allocate memory for maple bus dma */ retval = maple_get_dma_buffer(); if (retval) { dev_err(&maple_bus, "failed to allocate DMA buffers\n"); goto cleanup_basic; } /* set up DMA interrupt handler */ retval = maple_set_dma_interrupt_handler(); if (retval) { dev_err(&maple_bus, "bus failed to grab maple " "DMA IRQ\n"); goto cleanup_dma; } /* set up VBLANK interrupt handler */ retval = maple_set_vblank_interrupt_handler(); if (retval) { dev_err(&maple_bus, "bus failed to grab VBLANK IRQ\n"); goto cleanup_irq; } maple_queue_cache = KMEM_CACHE(maple_buffer, SLAB_HWCACHE_ALIGN); if (!maple_queue_cache) goto cleanup_bothirqs; INIT_LIST_HEAD(&maple_waitq); INIT_LIST_HEAD(&maple_sentq); /* setup maple ports */ for (i = 0; i < MAPLE_PORTS; i++) { checked[i] = false; empty[i] = false; mdev[i] = maple_alloc_dev(i, 0); if (!mdev[i]) { while (i-- > 0) maple_free_dev(mdev[i]); goto cleanup_cache; } baseunits[i] = mdev[i]; atomic_set(&mdev[i]->busy, 1); maple_add_packet(mdev[i], 0, MAPLE_COMMAND_DEVINFO, 0, NULL); subdevice_map[i] = 0; } maple_pnp_time = jiffies + HZ; /* prepare initial queue */ maple_send(); dev_info(&maple_bus, "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_unsupported_device.drv); cleanup_bus: bus_unregister(&maple_bus_type); cleanup_device: device_unregister(&maple_bus); cleanup: printk(KERN_ERR "Maple bus registration failed\n"); return retval; } /* Push init to later to ensure hardware gets detected */ fs_initcall(maple_bus_init);