diff options
Diffstat (limited to 'arch/arm/mach-mx5/dmaengine.c')
| -rw-r--r-- | arch/arm/mach-mx5/dmaengine.c | 641 |
1 files changed, 641 insertions, 0 deletions
diff --git a/arch/arm/mach-mx5/dmaengine.c b/arch/arm/mach-mx5/dmaengine.c new file mode 100644 index 000000000000..b8aad6c0b73f --- /dev/null +++ b/arch/arm/mach-mx5/dmaengine.c @@ -0,0 +1,641 @@ +/* + * Copyright (C) 2010 Freescale Semiconductor, Inc. All Rights Reserved. + * + * 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. + * + * 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. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/err.h> +#include <linux/list.h> +#include <linux/device.h> +#include <linux/dmapool.h> +#include <linux/proc_fs.h> +#include <linux/seq_file.h> +#include <linux/mutex.h> +#include <linux/spinlock.h> +#include <linux/io.h> +#include <mach/dmaengine.h> + +#include "dma-apbh.h" + +static void *mxs_dma_pool; +static int mxs_dma_alignment = MXS_DMA_ALIGNMENT; + +/* + * The mutex that arbitrates access to the array of structures that represent + * all the DMA channels in the system (see mxs_dma_channels, below). + */ + +static DEFINE_MUTEX(mxs_dma_mutex); + +/* + * The list of DMA drivers that manage various DMA channels. A DMA device + * driver registers to manage DMA channels by calling mxs_dma_device_register(). + */ + +static LIST_HEAD(mxs_dma_devices); + +/* + * The array of struct mxs_dma_chan that represent every DMA channel in the + * system. The index of the structure in the array indicates the specific DMA + * hardware it represents (see mach-mx28/include/mach/dma.h). + */ + +static struct mxs_dma_chan mxs_dma_channels[MXS_MAX_DMA_CHANNELS]; + +int mxs_dma_request(int channel, struct device *dev, const char *name) +{ + int ret = 0; + struct mxs_dma_chan *pchan; + + if ((channel < 0) || (channel >= MXS_MAX_DMA_CHANNELS)) + return -EINVAL; + + if (!dev || !name) + return -EINVAL; + pchan = mxs_dma_channels + channel; + mutex_lock(&mxs_dma_mutex); + if ((pchan->flags & MXS_DMA_FLAGS_VALID) != MXS_DMA_FLAGS_VALID) { + ret = -ENODEV; + goto out; + } + if (pchan->flags & MXS_DMA_FLAGS_ALLOCATED) { + ret = -EBUSY; + goto out; + } + pchan->flags |= MXS_DMA_FLAGS_ALLOCATED; + pchan->name = name; + pchan->dev = (unsigned long)dev; + pchan->active_num = 0; + pchan->pending_num = 0; + spin_lock_init(&pchan->lock); + INIT_LIST_HEAD(&pchan->active); + INIT_LIST_HEAD(&pchan->done); +out: + mutex_unlock(&mxs_dma_mutex); + return ret; +} +EXPORT_SYMBOL(mxs_dma_request); + +void mxs_dma_release(int channel, struct device *dev) +{ + struct mxs_dma_chan *pchan; + if ((channel < 0) || (channel >= MXS_MAX_DMA_CHANNELS)) + return; + pchan = mxs_dma_channels + channel; + + if (!(pchan->flags & MXS_DMA_FLAGS_ALLOCATED)) + return; + + if (pchan->flags & MXS_DMA_FLAGS_BUSY) + return; + + if (pchan->dev != (unsigned long)dev) + return; + + mutex_lock(&mxs_dma_mutex); + pchan->dev = 0; + pchan->active_num = 0; + pchan->pending_num = 0; + pchan->flags &= ~MXS_DMA_FLAGS_ALLOCATED; + mutex_unlock(&mxs_dma_mutex); +} +EXPORT_SYMBOL(mxs_dma_release); + +int mxs_dma_enable(int channel) +{ + int ret = 0; + unsigned long flags; + struct mxs_dma_chan *pchan; + struct mxs_dma_device *pdma; + if ((channel < 0) || (channel >= MXS_MAX_DMA_CHANNELS)) + return -EINVAL; + pchan = mxs_dma_channels + channel; + if (!(pchan->flags & MXS_DMA_FLAGS_ALLOCATED)) + return -EINVAL; + + pdma = pchan->dma; + mutex_lock(&mxs_dma_mutex); + spin_lock_irqsave(&pchan->lock, flags); + if (pchan->pending_num && pdma->enable) + ret = pdma->enable(pchan, channel - pdma->chan_base); + pchan->flags |= MXS_DMA_FLAGS_BUSY; + spin_unlock_irqrestore(&pchan->lock, flags); + mutex_unlock(&mxs_dma_mutex); + return ret; +} +EXPORT_SYMBOL(mxs_dma_enable); + +void mxs_dma_disable(int channel) +{ + unsigned long flags; + struct mxs_dma_chan *pchan; + struct mxs_dma_device *pdma; + if ((channel < 0) || (channel >= MXS_MAX_DMA_CHANNELS)) + return; + pchan = mxs_dma_channels + channel; + if (!(pchan->flags & MXS_DMA_FLAGS_ALLOCATED)) + return; + if (!(pchan->flags & MXS_DMA_FLAGS_BUSY)) + return; + pdma = pchan->dma; + mutex_lock(&mxs_dma_mutex); + spin_lock_irqsave(&pchan->lock, flags); + if (pdma->disable) + pdma->disable(pchan, channel - pdma->chan_base); + pchan->flags &= ~MXS_DMA_FLAGS_BUSY; + pchan->active_num = 0; + pchan->pending_num = 0; + list_splice_init(&pchan->active, &pchan->done); + spin_unlock_irqrestore(&pchan->lock, flags); + mutex_unlock(&mxs_dma_mutex); +} +EXPORT_SYMBOL(mxs_dma_disable); + +int mxs_dma_get_info(int channel, struct mxs_dma_info *info) +{ + struct mxs_dma_chan *pchan; + struct mxs_dma_device *pdma; + + if (!info) + return -EINVAL; + if ((channel < 0) || (channel >= MXS_MAX_DMA_CHANNELS)) + return -EINVAL; + pchan = mxs_dma_channels + channel; + if (!(pchan->flags & MXS_DMA_FLAGS_ALLOCATED)) + return -EFAULT; + pdma = pchan->dma; + if (pdma->info) + pdma->info(pdma, channel - pdma->chan_base, info); + return 0; +} +EXPORT_SYMBOL(mxs_dma_get_info); + +int mxs_dma_cooked(int channel, struct list_head *head) +{ + int sem; + unsigned long flags; + struct mxs_dma_chan *pchan; + struct list_head *p, *q; + struct mxs_dma_desc *pdesc; + if ((channel < 0) || (channel >= MXS_MAX_DMA_CHANNELS)) + return -EINVAL; + pchan = mxs_dma_channels + channel; + if (!(pchan->flags & MXS_DMA_FLAGS_ALLOCATED)) + return -EINVAL; + + sem = mxs_dma_read_semaphore(channel); + if (sem < 0) + return sem; + if (sem == pchan->active_num) + return 0; + BUG_ON(sem > pchan->active_num); + spin_lock_irqsave(&pchan->lock, flags); + list_for_each_safe(p, q, &pchan->active) { + if ((pchan->active_num) <= sem) + break; + pdesc = list_entry(p, struct mxs_dma_desc, node); + pdesc->flags &= ~MXS_DMA_DESC_READY; + if (head) + list_move_tail(p, head); + else + list_move_tail(p, &pchan->done); + if (pdesc->flags & MXS_DMA_DESC_LAST) + pchan->active_num--; + } + if (sem == 0) + pchan->flags &= ~MXS_DMA_FLAGS_BUSY; + spin_unlock_irqrestore(&pchan->lock, flags); + + BUG_ON(sem != pchan->active_num); + return 0; +} +EXPORT_SYMBOL(mxs_dma_cooked); + +void mxs_dma_reset(int channel) +{ + unsigned long flags; + struct mxs_dma_chan *pchan; + struct mxs_dma_device *pdma; + if ((channel < 0) || (channel >= MXS_MAX_DMA_CHANNELS)) + return; + pchan = mxs_dma_channels + channel; + if (!(pchan->flags & MXS_DMA_FLAGS_ALLOCATED)) + return; + pdma = pchan->dma; + spin_lock_irqsave(&pchan->lock, flags); + if (pdma->reset) + pdma->reset(pdma, channel - pdma->chan_base); + spin_unlock_irqrestore(&pchan->lock, flags); +} +EXPORT_SYMBOL(mxs_dma_reset); + +void mxs_dma_freeze(int channel) +{ + unsigned long flags; + struct mxs_dma_chan *pchan; + struct mxs_dma_device *pdma; + if ((channel < 0) || (channel >= MXS_MAX_DMA_CHANNELS)) + return; + pchan = mxs_dma_channels + channel; + if (!(pchan->flags & MXS_DMA_FLAGS_ALLOCATED)) + return; + pdma = pchan->dma; + spin_lock_irqsave(&pchan->lock, flags); + if (pdma->freeze) + pdma->freeze(pdma, channel - pdma->chan_base); + spin_unlock_irqrestore(&pchan->lock, flags); +} +EXPORT_SYMBOL(mxs_dma_freeze); + +void mxs_dma_unfreeze(int channel) +{ + unsigned long flags; + struct mxs_dma_chan *pchan; + struct mxs_dma_device *pdma; + if ((channel < 0) || (channel >= MXS_MAX_DMA_CHANNELS)) + return; + pchan = mxs_dma_channels + channel; + if (!(pchan->flags & MXS_DMA_FLAGS_ALLOCATED)) + return; + pdma = pchan->dma; + spin_lock_irqsave(&pchan->lock, flags); + if (pdma->unfreeze) + pdma->unfreeze(pdma, channel - pdma->chan_base); + spin_unlock_irqrestore(&pchan->lock, flags); +} +EXPORT_SYMBOL(mxs_dma_unfreeze); + +int mxs_dma_read_semaphore(int channel) +{ + int ret = -EINVAL; + unsigned long flags; + struct mxs_dma_chan *pchan; + struct mxs_dma_device *pdma; + if ((channel < 0) || (channel >= MXS_MAX_DMA_CHANNELS)) + return ret; + pchan = mxs_dma_channels + channel; + if (!(pchan->flags & MXS_DMA_FLAGS_ALLOCATED)) + return ret; + pdma = pchan->dma; + spin_lock_irqsave(&pchan->lock, flags); + if (pdma->read_semaphore) + ret = pdma->read_semaphore(pdma, channel - pdma->chan_base); + spin_unlock_irqrestore(&pchan->lock, flags); + return ret; +} +EXPORT_SYMBOL(mxs_dma_read_semaphore); + +void mxs_dma_enable_irq(int channel, int en) +{ + unsigned long flags; + struct mxs_dma_chan *pchan; + struct mxs_dma_device *pdma; + if ((channel < 0) || (channel >= MXS_MAX_DMA_CHANNELS)) + return; + pchan = mxs_dma_channels + channel; + if (!(pchan->flags & MXS_DMA_FLAGS_ALLOCATED)) + return; + pdma = pchan->dma; + spin_lock_irqsave(&pchan->lock, flags); + if (pdma->enable_irq) + pdma->enable_irq(pdma, channel - pdma->chan_base, en); + spin_unlock_irqrestore(&pchan->lock, flags); +} +EXPORT_SYMBOL(mxs_dma_enable_irq); + +int mxs_dma_irq_is_pending(int channel) +{ + int ret = 0; + unsigned long flags; + struct mxs_dma_chan *pchan; + struct mxs_dma_device *pdma; + if ((channel < 0) || (channel >= MXS_MAX_DMA_CHANNELS)) + return ret; + pchan = mxs_dma_channels + channel; + if (!(pchan->flags & MXS_DMA_FLAGS_ALLOCATED)) + return ret; + pdma = pchan->dma; + spin_lock_irqsave(&pchan->lock, flags); + if (pdma->irq_is_pending) + ret = pdma->irq_is_pending(pdma, channel - pdma->chan_base); + spin_unlock_irqrestore(&pchan->lock, flags); + return ret; +} +EXPORT_SYMBOL(mxs_dma_irq_is_pending); + +void mxs_dma_ack_irq(int channel) +{ + unsigned long flags; + struct mxs_dma_chan *pchan; + struct mxs_dma_device *pdma; + if ((channel < 0) || (channel >= MXS_MAX_DMA_CHANNELS)) + return; + pchan = mxs_dma_channels + channel; + if (!(pchan->flags & MXS_DMA_FLAGS_ALLOCATED)) + return; + pdma = pchan->dma; + spin_lock_irqsave(&pchan->lock, flags); + if (pdma->ack_irq) + pdma->ack_irq(pdma, channel - pdma->chan_base); + spin_unlock_irqrestore(&pchan->lock, flags); +} +EXPORT_SYMBOL(mxs_dma_ack_irq); + +void mxs_dma_set_target(int channel, int target) +{ + unsigned long flags; + struct mxs_dma_chan *pchan; + struct mxs_dma_device *pdma; + if ((channel < 0) || (channel >= MXS_MAX_DMA_CHANNELS)) + return; + pchan = mxs_dma_channels + channel; + if (!(pchan->flags & MXS_DMA_FLAGS_ALLOCATED)) + return; + if (pchan->flags & MXS_DMA_FLAGS_BUSY) + return; + pdma = pchan->dma; + spin_lock_irqsave(&pchan->lock, flags); + if (pdma->set_target) + pdma->set_target(pdma, channel - pdma->chan_base, target); + spin_unlock_irqrestore(&pchan->lock, flags); +} +EXPORT_SYMBOL(mxs_dma_set_target); + +/* mxs dma utility function */ +struct mxs_dma_desc *mxs_dma_alloc_desc(void) +{ + struct mxs_dma_desc *pdesc; + unsigned int address; + if (mxs_dma_pool == NULL) + return NULL; + + pdesc = dma_pool_alloc(mxs_dma_pool, GFP_KERNEL, &address); + if (pdesc == NULL) + return NULL; + memset(pdesc, 0, sizeof(*pdesc)); + pdesc->address = address; + return pdesc; +}; +EXPORT_SYMBOL(mxs_dma_alloc_desc); + +void mxs_dma_free_desc(struct mxs_dma_desc *pdesc) +{ + if (pdesc == NULL) + return; + + if (mxs_dma_pool == NULL) + return; + + dma_pool_free(mxs_dma_pool, pdesc, pdesc->address); +} +EXPORT_SYMBOL(mxs_dma_free_desc); + +int mxs_dma_desc_append(int channel, struct mxs_dma_desc *pdesc) +{ + int ret = 0; + unsigned long flags; + struct mxs_dma_chan *pchan; + struct mxs_dma_desc *last; + struct mxs_dma_device *pdma; + if ((channel < 0) || (channel >= MXS_MAX_DMA_CHANNELS)) + return -EINVAL; + pchan = mxs_dma_channels + channel; + if (!(pchan->flags & MXS_DMA_FLAGS_ALLOCATED)) + return -EINVAL; + pdma = pchan->dma; + pdesc->cmd.next = mxs_dma_cmd_address(pdesc); + pdesc->flags |= MXS_DMA_DESC_FIRST | MXS_DMA_DESC_LAST; + spin_lock_irqsave(&pchan->lock, flags); + if (!list_empty(&pchan->active)) { + + last = list_entry(pchan->active.prev, + struct mxs_dma_desc, node); + + pdesc->flags &= ~MXS_DMA_DESC_FIRST; + last->flags &= ~MXS_DMA_DESC_LAST; + + last->cmd.next = mxs_dma_cmd_address(pdesc); + last->cmd.cmd.bits.chain = 1; + } + pdesc->flags |= MXS_DMA_DESC_READY; + if (pdesc->flags & MXS_DMA_DESC_FIRST) + pchan->pending_num++; + list_add_tail(&pdesc->node, &pchan->active); +out: + spin_unlock_irqrestore(&pchan->lock, flags); + return ret; +} +EXPORT_SYMBOL(mxs_dma_desc_append); + +int mxs_dma_desc_add_list(int channel, struct list_head *head) +{ + int ret = 0, size = 0; + unsigned long flags; + struct mxs_dma_chan *pchan; + struct mxs_dma_device *pdma; + struct list_head *p; + struct mxs_dma_desc *prev = NULL, *pcur; + if ((channel < 0) || (channel >= MXS_MAX_DMA_CHANNELS)) + return -EINVAL; + pchan = mxs_dma_channels + channel; + if (!(pchan->flags & MXS_DMA_FLAGS_ALLOCATED)) + return -EINVAL; + + if (list_empty(head)) + return 0; + + pdma = pchan->dma; + list_for_each(p, head) { + pcur = list_entry(p, struct mxs_dma_desc, node); + if (!(pcur->cmd.cmd.bits.dec_sem || pcur->cmd.cmd.bits.chain)) + return -EINVAL; + if (prev) + prev->cmd.next = mxs_dma_cmd_address(pcur); + else + pcur->flags |= MXS_DMA_DESC_FIRST; + pcur->flags |= MXS_DMA_DESC_READY; + prev = pcur; + size++; + } + pcur = list_first_entry(head, struct mxs_dma_desc, node); + prev->cmd.next = mxs_dma_cmd_address(pcur); + prev->flags |= MXS_DMA_DESC_LAST; + + spin_lock_irqsave(&pchan->lock, flags); + if (!list_empty(&pchan->active)) { + pcur = list_entry(pchan->active.next, + struct mxs_dma_desc, node); + if (pcur->cmd.cmd.bits.dec_sem != prev->cmd.cmd.bits.dec_sem) { + ret = -EFAULT; + goto out; + } + prev->cmd.next = mxs_dma_cmd_address(pcur); + prev = list_entry(pchan->active.prev, + struct mxs_dma_desc, node); + pcur = list_first_entry(head, struct mxs_dma_desc, node); + pcur->flags &= ~MXS_DMA_DESC_FIRST; + prev->flags &= ~MXS_DMA_DESC_LAST; + prev->cmd.next = mxs_dma_cmd_address(pcur); + } + list_splice(head, &pchan->active); + pchan->pending_num += size; + if (!(pcur->cmd.cmd.bits.dec_sem) && (pcur->flags & MXS_DMA_DESC_FIRST)) + pchan->pending_num += 1; + else + pchan->pending_num += size; +out: + spin_unlock_irqrestore(&pchan->lock, flags); + return ret; +} +EXPORT_SYMBOL(mxs_dma_desc_add_list); + +int mxs_dma_get_cooked(int channel, struct list_head *head) +{ + unsigned long flags; + struct mxs_dma_chan *pchan; + if ((channel < 0) || (channel >= MXS_MAX_DMA_CHANNELS)) + return -EINVAL; + pchan = mxs_dma_channels + channel; + if (!(pchan->flags & MXS_DMA_FLAGS_ALLOCATED)) + return -EINVAL; + + if (head == NULL) + return 0; + + spin_lock_irqsave(&pchan->lock, flags); + list_splice(&pchan->done, head); + spin_unlock_irqrestore(&pchan->lock, flags); + return 0; +} +EXPORT_SYMBOL(mxs_dma_get_cooked); + +int mxs_dma_device_register(struct mxs_dma_device *pdev) +{ + int i; + struct mxs_dma_chan *pchan; + + if (pdev == NULL || !pdev->chan_num) + return -EINVAL; + + if ((pdev->chan_base >= MXS_MAX_DMA_CHANNELS) || + ((pdev->chan_base + pdev->chan_num) > MXS_MAX_DMA_CHANNELS)) + return -EINVAL; + + mutex_lock(&mxs_dma_mutex); + pchan = mxs_dma_channels + pdev->chan_base; + for (i = 0; i < pdev->chan_num; i++, pchan++) { + pchan->dma = pdev; + pchan->flags = MXS_DMA_FLAGS_VALID; + } + list_add(&pdev->node, &mxs_dma_devices); + mutex_unlock(&mxs_dma_mutex); + return 0; +} +EXPORT_SYMBOL(mxs_dma_device_register); + +static int __init mxs_dma_alignment_setup(char *line) +{ + get_option(&line, &mxs_dma_alignment); + mxs_dma_alignment = (mxs_dma_alignment + 3) & (~3); + mxs_dma_alignment = max(mxs_dma_alignment, MXS_DMA_ALIGNMENT); + return 1; +}; + +__setup("mxs-dma-alignment=", mxs_dma_alignment_setup); + +static int mxs_dmaengine_init(void) +{ + mxs_dma_pool = dma_pool_create("mxs_dma", NULL, + sizeof(struct mxs_dma_desc), + mxs_dma_alignment, PAGE_SIZE); + if (mxs_dma_pool == NULL) + return -ENOMEM; + return 0; +} + +subsys_initcall(mxs_dmaengine_init); + +#ifdef CONFIG_PROC_FS + +static void *mxs_dma_proc_seq_start(struct seq_file *file, loff_t * index) +{ + if (*index >= MXS_MAX_DMA_CHANNELS) + return NULL; + return mxs_dma_channels + *index; +} + +static void *mxs_dma_proc_seq_next(struct seq_file *file, void *data, + loff_t *index) +{ + if (data == NULL) + return NULL; + + if (*index >= MXS_MAX_DMA_CHANNELS) + return NULL; + + return mxs_dma_channels + (*index)++; +} + +static void mxs_dma_proc_seq_stop(struct seq_file *file, void *data) +{ +} + +static int mxs_dma_proc_seq_show(struct seq_file *file, void *data) +{ + int result; + struct mxs_dma_chan *pchan = (struct mxs_dma_chan *)data; + struct mxs_dma_device *pdev = pchan->dma; + result = seq_printf(file, "%s-channel%-d (%s)\n", + pdev->name, + pchan - mxs_dma_channels, + pchan->name ? pchan->name : "idle"); + return result; +} + +static const struct seq_operations mxc_dma_proc_seq_ops = { + .start = mxs_dma_proc_seq_start, + .next = mxs_dma_proc_seq_next, + .stop = mxs_dma_proc_seq_stop, + .show = mxs_dma_proc_seq_show +}; + +static int mxs_dma_proc_open(struct inode *inode, struct file *file) +{ + return seq_open(file, &mxc_dma_proc_seq_ops); +} + +static const struct file_operations mxs_dma_proc_info_ops = { + .open = mxs_dma_proc_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; + +static int __init mxs_dmaengine_info_init(void) +{ + struct proc_dir_entry *res; + res = create_proc_entry("dma-engine", 0, NULL); + if (!res) { + printk(KERN_ERR "Failed to create dma info file \n"); + return -ENOMEM; + } + res->proc_fops = &mxs_dma_proc_info_ops; + return 0; +} + +late_initcall(mxs_dmaengine_info_init); +#endif |