| /* |
| * timb_dma.c timberdale FPGA DMA driver |
| * Copyright (c) 2010 Intel Corporation |
| * |
| * 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. |
| * |
| * 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., 675 Mass Ave, Cambridge, MA 02139, USA. |
| */ |
| |
| /* Supports: |
| * Timberdale FPGA DMA engine |
| */ |
| |
| #include <linux/dmaengine.h> |
| #include <linux/dma-mapping.h> |
| #include <linux/init.h> |
| #include <linux/interrupt.h> |
| #include <linux/io.h> |
| #include <linux/module.h> |
| #include <linux/platform_device.h> |
| |
| #include <linux/timb_dma.h> |
| |
| #define DRIVER_NAME "timb-dma" |
| |
| /* Global DMA registers */ |
| #define TIMBDMA_ACR 0x34 |
| #define TIMBDMA_32BIT_ADDR 0x01 |
| |
| #define TIMBDMA_ISR 0x080000 |
| #define TIMBDMA_IPR 0x080004 |
| #define TIMBDMA_IER 0x080008 |
| |
| /* Channel specific registers */ |
| /* RX instances base addresses are 0x00, 0x40, 0x80 ... |
| * TX instances base addresses are 0x18, 0x58, 0x98 ... |
| */ |
| #define TIMBDMA_INSTANCE_OFFSET 0x40 |
| #define TIMBDMA_INSTANCE_TX_OFFSET 0x18 |
| |
| /* RX registers, relative the instance base */ |
| #define TIMBDMA_OFFS_RX_DHAR 0x00 |
| #define TIMBDMA_OFFS_RX_DLAR 0x04 |
| #define TIMBDMA_OFFS_RX_LR 0x0C |
| #define TIMBDMA_OFFS_RX_BLR 0x10 |
| #define TIMBDMA_OFFS_RX_ER 0x14 |
| #define TIMBDMA_RX_EN 0x01 |
| /* bytes per Row, video specific register |
| * which is placed after the TX registers... |
| */ |
| #define TIMBDMA_OFFS_RX_BPRR 0x30 |
| |
| /* TX registers, relative the instance base */ |
| #define TIMBDMA_OFFS_TX_DHAR 0x00 |
| #define TIMBDMA_OFFS_TX_DLAR 0x04 |
| #define TIMBDMA_OFFS_TX_BLR 0x0C |
| #define TIMBDMA_OFFS_TX_LR 0x14 |
| |
| |
| #define TIMB_DMA_DESC_SIZE 8 |
| |
| struct timb_dma_desc { |
| struct list_head desc_node; |
| struct dma_async_tx_descriptor txd; |
| u8 *desc_list; |
| unsigned int desc_list_len; |
| bool interrupt; |
| }; |
| |
| struct timb_dma_chan { |
| struct dma_chan chan; |
| void __iomem *membase; |
| spinlock_t lock; /* Used to protect data structures, |
| especially the lists and descriptors, |
| from races between the tasklet and calls |
| from above */ |
| dma_cookie_t last_completed_cookie; |
| bool ongoing; |
| struct list_head active_list; |
| struct list_head queue; |
| struct list_head free_list; |
| unsigned int bytes_per_line; |
| enum dma_data_direction direction; |
| unsigned int descs; /* Descriptors to allocate */ |
| unsigned int desc_elems; /* number of elems per descriptor */ |
| }; |
| |
| struct timb_dma { |
| struct dma_device dma; |
| void __iomem *membase; |
| struct tasklet_struct tasklet; |
| struct timb_dma_chan channels[0]; |
| }; |
| |
| static struct device *chan2dev(struct dma_chan *chan) |
| { |
| return &chan->dev->device; |
| } |
| static struct device *chan2dmadev(struct dma_chan *chan) |
| { |
| return chan2dev(chan)->parent->parent; |
| } |
| |
| static struct timb_dma *tdchantotd(struct timb_dma_chan *td_chan) |
| { |
| int id = td_chan->chan.chan_id; |
| return (struct timb_dma *)((u8 *)td_chan - |
| id * sizeof(struct timb_dma_chan) - sizeof(struct timb_dma)); |
| } |
| |
| /* Must be called with the spinlock held */ |
| static void __td_enable_chan_irq(struct timb_dma_chan *td_chan) |
| { |
| int id = td_chan->chan.chan_id; |
| struct timb_dma *td = tdchantotd(td_chan); |
| u32 ier; |
| |
| /* enable interrupt for this channel */ |
| ier = ioread32(td->membase + TIMBDMA_IER); |
| ier |= 1 << id; |
| dev_dbg(chan2dev(&td_chan->chan), "Enabling irq: %d, IER: 0x%x\n", id, |
| ier); |
| iowrite32(ier, td->membase + TIMBDMA_IER); |
| } |
| |
| /* Should be called with the spinlock held */ |
| static bool __td_dma_done_ack(struct timb_dma_chan *td_chan) |
| { |
| int id = td_chan->chan.chan_id; |
| struct timb_dma *td = (struct timb_dma *)((u8 *)td_chan - |
| id * sizeof(struct timb_dma_chan) - sizeof(struct timb_dma)); |
| u32 isr; |
| bool done = false; |
| |
| dev_dbg(chan2dev(&td_chan->chan), "Checking irq: %d, td: %p\n", id, td); |
| |
| isr = ioread32(td->membase + TIMBDMA_ISR) & (1 << id); |
| if (isr) { |
| iowrite32(isr, td->membase + TIMBDMA_ISR); |
| done = true; |
| } |
| |
| return done; |
| } |
| |
| static void __td_unmap_desc(struct timb_dma_chan *td_chan, const u8 *dma_desc, |
| bool single) |
| { |
| dma_addr_t addr; |
| int len; |
| |
| addr = (dma_desc[7] << 24) | (dma_desc[6] << 16) | (dma_desc[5] << 8) | |
| dma_desc[4]; |
| |
| len = (dma_desc[3] << 8) | dma_desc[2]; |
| |
| if (single) |
| dma_unmap_single(chan2dev(&td_chan->chan), addr, len, |
| td_chan->direction); |
| else |
| dma_unmap_page(chan2dev(&td_chan->chan), addr, len, |
| td_chan->direction); |
| } |
| |
| static void __td_unmap_descs(struct timb_dma_desc *td_desc, bool single) |
| { |
| struct timb_dma_chan *td_chan = container_of(td_desc->txd.chan, |
| struct timb_dma_chan, chan); |
| u8 *descs; |
| |
| for (descs = td_desc->desc_list; ; descs += TIMB_DMA_DESC_SIZE) { |
| __td_unmap_desc(td_chan, descs, single); |
| if (descs[0] & 0x02) |
| break; |
| } |
| } |
| |
| static int td_fill_desc(struct timb_dma_chan *td_chan, u8 *dma_desc, |
| struct scatterlist *sg, bool last) |
| { |
| if (sg_dma_len(sg) > USHORT_MAX) { |
| dev_err(chan2dev(&td_chan->chan), "Too big sg element\n"); |
| return -EINVAL; |
| } |
| |
| /* length must be word aligned */ |
| if (sg_dma_len(sg) % sizeof(u32)) { |
| dev_err(chan2dev(&td_chan->chan), "Incorrect length: %d\n", |
| sg_dma_len(sg)); |
| return -EINVAL; |
| } |
| |
| dev_dbg(chan2dev(&td_chan->chan), "desc: %p, addr: %p\n", |
| dma_desc, (void *)sg_dma_address(sg)); |
| |
| dma_desc[7] = (sg_dma_address(sg) >> 24) & 0xff; |
| dma_desc[6] = (sg_dma_address(sg) >> 16) & 0xff; |
| dma_desc[5] = (sg_dma_address(sg) >> 8) & 0xff; |
| dma_desc[4] = (sg_dma_address(sg) >> 0) & 0xff; |
| |
| dma_desc[3] = (sg_dma_len(sg) >> 8) & 0xff; |
| dma_desc[2] = (sg_dma_len(sg) >> 0) & 0xff; |
| |
| dma_desc[1] = 0x00; |
| dma_desc[0] = 0x21 | (last ? 0x02 : 0); /* tran, valid */ |
| |
| return 0; |
| } |
| |
| /* Must be called with the spinlock held */ |
| static void __td_start_dma(struct timb_dma_chan *td_chan) |
| { |
| struct timb_dma_desc *td_desc; |
| |
| if (td_chan->ongoing) { |
| dev_err(chan2dev(&td_chan->chan), |
| "Transfer already ongoing\n"); |
| return; |
| } |
| |
| td_desc = list_entry(td_chan->active_list.next, struct timb_dma_desc, |
| desc_node); |
| |
| dev_dbg(chan2dev(&td_chan->chan), |
| "td_chan: %p, chan: %d, membase: %p\n", |
| td_chan, td_chan->chan.chan_id, td_chan->membase); |
| |
| if (td_chan->direction == DMA_FROM_DEVICE) { |
| |
| /* descriptor address */ |
| iowrite32(0, td_chan->membase + TIMBDMA_OFFS_RX_DHAR); |
| iowrite32(td_desc->txd.phys, td_chan->membase + |
| TIMBDMA_OFFS_RX_DLAR); |
| /* Bytes per line */ |
| iowrite32(td_chan->bytes_per_line, td_chan->membase + |
| TIMBDMA_OFFS_RX_BPRR); |
| /* enable RX */ |
| iowrite32(TIMBDMA_RX_EN, td_chan->membase + TIMBDMA_OFFS_RX_ER); |
| } else { |
| /* address high */ |
| iowrite32(0, td_chan->membase + TIMBDMA_OFFS_TX_DHAR); |
| iowrite32(td_desc->txd.phys, td_chan->membase + |
| TIMBDMA_OFFS_TX_DLAR); |
| } |
| |
| td_chan->ongoing = true; |
| |
| if (td_desc->interrupt) |
| __td_enable_chan_irq(td_chan); |
| } |
| |
| static void __td_finish(struct timb_dma_chan *td_chan) |
| { |
| dma_async_tx_callback callback; |
| void *param; |
| struct dma_async_tx_descriptor *txd; |
| struct timb_dma_desc *td_desc; |
| |
| /* can happen if the descriptor is canceled */ |
| if (list_empty(&td_chan->active_list)) |
| return; |
| |
| td_desc = list_entry(td_chan->active_list.next, struct timb_dma_desc, |
| desc_node); |
| txd = &td_desc->txd; |
| |
| dev_dbg(chan2dev(&td_chan->chan), "descriptor %u complete\n", |
| txd->cookie); |
| |
| /* make sure to stop the transfer */ |
| if (td_chan->direction == DMA_FROM_DEVICE) |
| iowrite32(0, td_chan->membase + TIMBDMA_OFFS_RX_ER); |
| /* Currently no support for stopping DMA transfers |
| else |
| iowrite32(0, td_chan->membase + TIMBDMA_OFFS_TX_DLAR); |
| */ |
| td_chan->last_completed_cookie = txd->cookie; |
| td_chan->ongoing = false; |
| |
| callback = txd->callback; |
| param = txd->callback_param; |
| |
| list_move(&td_desc->desc_node, &td_chan->free_list); |
| |
| if (!(txd->flags & DMA_COMPL_SKIP_SRC_UNMAP)) |
| __td_unmap_descs(td_desc, |
| txd->flags & DMA_COMPL_SRC_UNMAP_SINGLE); |
| |
| /* |
| * The API requires that no submissions are done from a |
| * callback, so we don't need to drop the lock here |
| */ |
| if (callback) |
| callback(param); |
| } |
| |
| static u32 __td_ier_mask(struct timb_dma *td) |
| { |
| int i; |
| u32 ret = 0; |
| |
| for (i = 0; i < td->dma.chancnt; i++) { |
| struct timb_dma_chan *td_chan = td->channels + i; |
| if (td_chan->ongoing) { |
| struct timb_dma_desc *td_desc = |
| list_entry(td_chan->active_list.next, |
| struct timb_dma_desc, desc_node); |
| if (td_desc->interrupt) |
| ret |= 1 << i; |
| } |
| } |
| |
| return ret; |
| } |
| |
| static void __td_start_next(struct timb_dma_chan *td_chan) |
| { |
| struct timb_dma_desc *td_desc; |
| |
| BUG_ON(list_empty(&td_chan->queue)); |
| BUG_ON(td_chan->ongoing); |
| |
| td_desc = list_entry(td_chan->queue.next, struct timb_dma_desc, |
| desc_node); |
| |
| dev_dbg(chan2dev(&td_chan->chan), "%s: started %u\n", |
| __func__, td_desc->txd.cookie); |
| |
| list_move(&td_desc->desc_node, &td_chan->active_list); |
| __td_start_dma(td_chan); |
| } |
| |
| static dma_cookie_t td_tx_submit(struct dma_async_tx_descriptor *txd) |
| { |
| struct timb_dma_desc *td_desc = container_of(txd, struct timb_dma_desc, |
| txd); |
| struct timb_dma_chan *td_chan = container_of(txd->chan, |
| struct timb_dma_chan, chan); |
| dma_cookie_t cookie; |
| |
| spin_lock_bh(&td_chan->lock); |
| |
| cookie = txd->chan->cookie; |
| if (++cookie < 0) |
| cookie = 1; |
| txd->chan->cookie = cookie; |
| txd->cookie = cookie; |
| |
| if (list_empty(&td_chan->active_list)) { |
| dev_dbg(chan2dev(txd->chan), "%s: started %u\n", __func__, |
| txd->cookie); |
| list_add_tail(&td_desc->desc_node, &td_chan->active_list); |
| __td_start_dma(td_chan); |
| } else { |
| dev_dbg(chan2dev(txd->chan), "tx_submit: queued %u\n", |
| txd->cookie); |
| |
| list_add_tail(&td_desc->desc_node, &td_chan->queue); |
| } |
| |
| spin_unlock_bh(&td_chan->lock); |
| |
| return cookie; |
| } |
| |
| static struct timb_dma_desc *td_alloc_init_desc(struct timb_dma_chan *td_chan) |
| { |
| struct dma_chan *chan = &td_chan->chan; |
| struct timb_dma_desc *td_desc; |
| int err; |
| |
| td_desc = kzalloc(sizeof(struct timb_dma_desc), GFP_KERNEL); |
| if (!td_desc) { |
| dev_err(chan2dev(chan), "Failed to alloc descriptor\n"); |
| goto err; |
| } |
| |
| td_desc->desc_list_len = td_chan->desc_elems * TIMB_DMA_DESC_SIZE; |
| |
| td_desc->desc_list = kzalloc(td_desc->desc_list_len, GFP_KERNEL); |
| if (!td_desc->desc_list) { |
| dev_err(chan2dev(chan), "Failed to alloc descriptor\n"); |
| goto err; |
| } |
| |
| dma_async_tx_descriptor_init(&td_desc->txd, chan); |
| td_desc->txd.tx_submit = td_tx_submit; |
| td_desc->txd.flags = DMA_CTRL_ACK; |
| |
| td_desc->txd.phys = dma_map_single(chan2dmadev(chan), |
| td_desc->desc_list, td_desc->desc_list_len, DMA_TO_DEVICE); |
| |
| err = dma_mapping_error(chan2dmadev(chan), td_desc->txd.phys); |
| if (err) { |
| dev_err(chan2dev(chan), "DMA mapping error: %d\n", err); |
| goto err; |
| } |
| |
| return td_desc; |
| err: |
| kfree(td_desc->desc_list); |
| kfree(td_desc); |
| |
| return NULL; |
| |
| } |
| |
| static void td_free_desc(struct timb_dma_desc *td_desc) |
| { |
| dev_dbg(chan2dev(td_desc->txd.chan), "Freeing desc: %p\n", td_desc); |
| dma_unmap_single(chan2dmadev(td_desc->txd.chan), td_desc->txd.phys, |
| td_desc->desc_list_len, DMA_TO_DEVICE); |
| |
| kfree(td_desc->desc_list); |
| kfree(td_desc); |
| } |
| |
| static void td_desc_put(struct timb_dma_chan *td_chan, |
| struct timb_dma_desc *td_desc) |
| { |
| dev_dbg(chan2dev(&td_chan->chan), "Putting desc: %p\n", td_desc); |
| |
| spin_lock_bh(&td_chan->lock); |
| list_add(&td_desc->desc_node, &td_chan->free_list); |
| spin_unlock_bh(&td_chan->lock); |
| } |
| |
| static struct timb_dma_desc *td_desc_get(struct timb_dma_chan *td_chan) |
| { |
| struct timb_dma_desc *td_desc, *_td_desc; |
| struct timb_dma_desc *ret = NULL; |
| |
| spin_lock_bh(&td_chan->lock); |
| list_for_each_entry_safe(td_desc, _td_desc, &td_chan->free_list, |
| desc_node) { |
| if (async_tx_test_ack(&td_desc->txd)) { |
| list_del(&td_desc->desc_node); |
| ret = td_desc; |
| break; |
| } |
| dev_dbg(chan2dev(&td_chan->chan), "desc %p not ACKed\n", |
| td_desc); |
| } |
| spin_unlock_bh(&td_chan->lock); |
| |
| return ret; |
| } |
| |
| static int td_alloc_chan_resources(struct dma_chan *chan) |
| { |
| struct timb_dma_chan *td_chan = |
| container_of(chan, struct timb_dma_chan, chan); |
| int i; |
| |
| dev_dbg(chan2dev(chan), "%s: entry\n", __func__); |
| |
| BUG_ON(!list_empty(&td_chan->free_list)); |
| for (i = 0; i < td_chan->descs; i++) { |
| struct timb_dma_desc *td_desc = td_alloc_init_desc(td_chan); |
| if (!td_desc) { |
| if (i) |
| break; |
| else { |
| dev_err(chan2dev(chan), |
| "Couldnt allocate any descriptors\n"); |
| return -ENOMEM; |
| } |
| } |
| |
| td_desc_put(td_chan, td_desc); |
| } |
| |
| spin_lock_bh(&td_chan->lock); |
| td_chan->last_completed_cookie = 1; |
| chan->cookie = 1; |
| spin_unlock_bh(&td_chan->lock); |
| |
| return 0; |
| } |
| |
| static void td_free_chan_resources(struct dma_chan *chan) |
| { |
| struct timb_dma_chan *td_chan = |
| container_of(chan, struct timb_dma_chan, chan); |
| struct timb_dma_desc *td_desc, *_td_desc; |
| LIST_HEAD(list); |
| |
| dev_dbg(chan2dev(chan), "%s: Entry\n", __func__); |
| |
| /* check that all descriptors are free */ |
| BUG_ON(!list_empty(&td_chan->active_list)); |
| BUG_ON(!list_empty(&td_chan->queue)); |
| |
| spin_lock_bh(&td_chan->lock); |
| list_splice_init(&td_chan->free_list, &list); |
| spin_unlock_bh(&td_chan->lock); |
| |
| list_for_each_entry_safe(td_desc, _td_desc, &list, desc_node) { |
| dev_dbg(chan2dev(chan), "%s: Freeing desc: %p\n", __func__, |
| td_desc); |
| td_free_desc(td_desc); |
| } |
| } |
| |
| static enum dma_status td_is_tx_complete(struct dma_chan *chan, |
| dma_cookie_t cookie, dma_cookie_t *done, dma_cookie_t *used) |
| { |
| struct timb_dma_chan *td_chan = |
| container_of(chan, struct timb_dma_chan, chan); |
| dma_cookie_t last_used; |
| dma_cookie_t last_complete; |
| int ret; |
| |
| dev_dbg(chan2dev(chan), "%s: Entry\n", __func__); |
| |
| last_complete = td_chan->last_completed_cookie; |
| last_used = chan->cookie; |
| |
| ret = dma_async_is_complete(cookie, last_complete, last_used); |
| |
| if (done) |
| *done = last_complete; |
| if (used) |
| *used = last_used; |
| |
| dev_dbg(chan2dev(chan), |
| "%s: exit, ret: %d, last_complete: %d, last_used: %d\n", |
| __func__, ret, last_complete, last_used); |
| |
| return ret; |
| } |
| |
| static void td_issue_pending(struct dma_chan *chan) |
| { |
| struct timb_dma_chan *td_chan = |
| container_of(chan, struct timb_dma_chan, chan); |
| |
| dev_dbg(chan2dev(chan), "%s: Entry\n", __func__); |
| spin_lock_bh(&td_chan->lock); |
| |
| if (!list_empty(&td_chan->active_list)) |
| /* transfer ongoing */ |
| if (__td_dma_done_ack(td_chan)) |
| __td_finish(td_chan); |
| |
| if (list_empty(&td_chan->active_list) && !list_empty(&td_chan->queue)) |
| __td_start_next(td_chan); |
| |
| spin_unlock_bh(&td_chan->lock); |
| } |
| |
| static struct dma_async_tx_descriptor *td_prep_slave_sg(struct dma_chan *chan, |
| struct scatterlist *sgl, unsigned int sg_len, |
| enum dma_data_direction direction, unsigned long flags) |
| { |
| struct timb_dma_chan *td_chan = |
| container_of(chan, struct timb_dma_chan, chan); |
| struct timb_dma_desc *td_desc; |
| struct scatterlist *sg; |
| unsigned int i; |
| unsigned int desc_usage = 0; |
| |
| if (!sgl || !sg_len) { |
| dev_err(chan2dev(chan), "%s: No SG list\n", __func__); |
| return NULL; |
| } |
| |
| /* even channels are for RX, odd for TX */ |
| if (td_chan->direction != direction) { |
| dev_err(chan2dev(chan), |
| "Requesting channel in wrong direction\n"); |
| return NULL; |
| } |
| |
| td_desc = td_desc_get(td_chan); |
| if (!td_desc) { |
| dev_err(chan2dev(chan), "Not enough descriptors available\n"); |
| return NULL; |
| } |
| |
| td_desc->interrupt = (flags & DMA_PREP_INTERRUPT) != 0; |
| |
| for_each_sg(sgl, sg, sg_len, i) { |
| int err; |
| if (desc_usage > td_desc->desc_list_len) { |
| dev_err(chan2dev(chan), "No descriptor space\n"); |
| return NULL; |
| } |
| |
| err = td_fill_desc(td_chan, td_desc->desc_list + desc_usage, sg, |
| i == (sg_len - 1)); |
| if (err) { |
| dev_err(chan2dev(chan), "Failed to update desc: %d\n", |
| err); |
| td_desc_put(td_chan, td_desc); |
| return NULL; |
| } |
| desc_usage += TIMB_DMA_DESC_SIZE; |
| } |
| |
| dma_sync_single_for_device(chan2dmadev(chan), td_desc->txd.phys, |
| td_desc->desc_list_len, DMA_TO_DEVICE); |
| |
| return &td_desc->txd; |
| } |
| |
| static void td_terminate_all(struct dma_chan *chan) |
| { |
| struct timb_dma_chan *td_chan = |
| container_of(chan, struct timb_dma_chan, chan); |
| struct timb_dma_desc *td_desc, *_td_desc; |
| |
| dev_dbg(chan2dev(chan), "%s: Entry\n", __func__); |
| |
| /* first the easy part, put the queue into the free list */ |
| spin_lock_bh(&td_chan->lock); |
| list_for_each_entry_safe(td_desc, _td_desc, &td_chan->queue, |
| desc_node) |
| list_move(&td_desc->desc_node, &td_chan->free_list); |
| |
| /* now tear down the runnning */ |
| __td_finish(td_chan); |
| spin_unlock_bh(&td_chan->lock); |
| } |
| |
| static void td_tasklet(unsigned long data) |
| { |
| struct timb_dma *td = (struct timb_dma *)data; |
| u32 isr; |
| u32 ipr; |
| u32 ier; |
| int i; |
| |
| isr = ioread32(td->membase + TIMBDMA_ISR); |
| ipr = isr & __td_ier_mask(td); |
| |
| /* ack the interrupts */ |
| iowrite32(ipr, td->membase + TIMBDMA_ISR); |
| |
| for (i = 0; i < td->dma.chancnt; i++) |
| if (ipr & (1 << i)) { |
| struct timb_dma_chan *td_chan = td->channels + i; |
| spin_lock(&td_chan->lock); |
| __td_finish(td_chan); |
| if (!list_empty(&td_chan->queue)) |
| __td_start_next(td_chan); |
| spin_unlock(&td_chan->lock); |
| } |
| |
| ier = __td_ier_mask(td); |
| iowrite32(ier, td->membase + TIMBDMA_IER); |
| } |
| |
| |
| static irqreturn_t td_irq(int irq, void *devid) |
| { |
| struct timb_dma *td = devid; |
| u32 ipr = ioread32(td->membase + TIMBDMA_IPR); |
| |
| if (ipr) { |
| /* disable interrupts, will be re-enabled in tasklet */ |
| iowrite32(0, td->membase + TIMBDMA_IER); |
| |
| tasklet_schedule(&td->tasklet); |
| |
| return IRQ_HANDLED; |
| } else |
| return IRQ_NONE; |
| } |
| |
| |
| static int __devinit td_probe(struct platform_device *pdev) |
| { |
| struct timb_dma_platform_data *pdata = pdev->dev.platform_data; |
| struct timb_dma *td; |
| struct resource *iomem; |
| int irq; |
| int err; |
| int i; |
| |
| if (!pdata) { |
| dev_err(&pdev->dev, "No platform data\n"); |
| return -EINVAL; |
| } |
| |
| iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| if (!iomem) |
| return -EINVAL; |
| |
| irq = platform_get_irq(pdev, 0); |
| if (irq < 0) |
| return irq; |
| |
| if (!request_mem_region(iomem->start, resource_size(iomem), |
| DRIVER_NAME)) |
| return -EBUSY; |
| |
| td = kzalloc(sizeof(struct timb_dma) + |
| sizeof(struct timb_dma_chan) * pdata->nr_channels, GFP_KERNEL); |
| if (!td) { |
| err = -ENOMEM; |
| goto err_release_region; |
| } |
| |
| dev_dbg(&pdev->dev, "Allocated TD: %p\n", td); |
| |
| td->membase = ioremap(iomem->start, resource_size(iomem)); |
| if (!td->membase) { |
| dev_err(&pdev->dev, "Failed to remap I/O memory\n"); |
| err = -ENOMEM; |
| goto err_free_mem; |
| } |
| |
| /* 32bit addressing */ |
| iowrite32(TIMBDMA_32BIT_ADDR, td->membase + TIMBDMA_ACR); |
| |
| /* disable and clear any interrupts */ |
| iowrite32(0x0, td->membase + TIMBDMA_IER); |
| iowrite32(0xFFFFFFFF, td->membase + TIMBDMA_ISR); |
| |
| tasklet_init(&td->tasklet, td_tasklet, (unsigned long)td); |
| |
| err = request_irq(irq, td_irq, IRQF_SHARED, DRIVER_NAME, td); |
| if (err) { |
| dev_err(&pdev->dev, "Failed to request IRQ\n"); |
| goto err_tasklet_kill; |
| } |
| |
| td->dma.device_alloc_chan_resources = td_alloc_chan_resources; |
| td->dma.device_free_chan_resources = td_free_chan_resources; |
| td->dma.device_is_tx_complete = td_is_tx_complete; |
| td->dma.device_issue_pending = td_issue_pending; |
| |
| dma_cap_set(DMA_SLAVE, td->dma.cap_mask); |
| dma_cap_set(DMA_PRIVATE, td->dma.cap_mask); |
| td->dma.device_prep_slave_sg = td_prep_slave_sg; |
| td->dma.device_terminate_all = td_terminate_all; |
| |
| td->dma.dev = &pdev->dev; |
| |
| INIT_LIST_HEAD(&td->dma.channels); |
| |
| for (i = 0; i < pdata->nr_channels; i++, td->dma.chancnt++) { |
| struct timb_dma_chan *td_chan = &td->channels[i]; |
| struct timb_dma_platform_data_channel *pchan = |
| pdata->channels + i; |
| |
| /* even channels are RX, odd are TX */ |
| if (((i % 2) && pchan->rx) || (!(i % 2) && !pchan->rx)) { |
| dev_err(&pdev->dev, "Wrong channel configuration\n"); |
| err = -EINVAL; |
| goto err_tasklet_kill; |
| } |
| |
| td_chan->chan.device = &td->dma; |
| td_chan->chan.cookie = 1; |
| td_chan->chan.chan_id = i; |
| spin_lock_init(&td_chan->lock); |
| INIT_LIST_HEAD(&td_chan->active_list); |
| INIT_LIST_HEAD(&td_chan->queue); |
| INIT_LIST_HEAD(&td_chan->free_list); |
| |
| td_chan->descs = pchan->descriptors; |
| td_chan->desc_elems = pchan->descriptor_elements; |
| td_chan->bytes_per_line = pchan->bytes_per_line; |
| td_chan->direction = pchan->rx ? DMA_FROM_DEVICE : |
| DMA_TO_DEVICE; |
| |
| td_chan->membase = td->membase + |
| (i / 2) * TIMBDMA_INSTANCE_OFFSET + |
| (pchan->rx ? 0 : TIMBDMA_INSTANCE_TX_OFFSET); |
| |
| dev_dbg(&pdev->dev, "Chan: %d, membase: %p\n", |
| i, td_chan->membase); |
| |
| list_add_tail(&td_chan->chan.device_node, &td->dma.channels); |
| } |
| |
| err = dma_async_device_register(&td->dma); |
| if (err) { |
| dev_err(&pdev->dev, "Failed to register async device\n"); |
| goto err_free_irq; |
| } |
| |
| platform_set_drvdata(pdev, td); |
| |
| dev_dbg(&pdev->dev, "Probe result: %d\n", err); |
| return err; |
| |
| err_free_irq: |
| free_irq(irq, td); |
| err_tasklet_kill: |
| tasklet_kill(&td->tasklet); |
| iounmap(td->membase); |
| err_free_mem: |
| kfree(td); |
| err_release_region: |
| release_mem_region(iomem->start, resource_size(iomem)); |
| |
| return err; |
| |
| } |
| |
| static int __devexit td_remove(struct platform_device *pdev) |
| { |
| struct timb_dma *td = platform_get_drvdata(pdev); |
| struct resource *iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| int irq = platform_get_irq(pdev, 0); |
| |
| dma_async_device_unregister(&td->dma); |
| free_irq(irq, td); |
| tasklet_kill(&td->tasklet); |
| iounmap(td->membase); |
| kfree(td); |
| release_mem_region(iomem->start, resource_size(iomem)); |
| |
| platform_set_drvdata(pdev, NULL); |
| |
| dev_dbg(&pdev->dev, "Removed...\n"); |
| return 0; |
| } |
| |
| static struct platform_driver td_driver = { |
| .driver = { |
| .name = DRIVER_NAME, |
| .owner = THIS_MODULE, |
| }, |
| .probe = td_probe, |
| .remove = __exit_p(td_remove), |
| }; |
| |
| static int __init td_init(void) |
| { |
| return platform_driver_register(&td_driver); |
| } |
| module_init(td_init); |
| |
| static void __exit td_exit(void) |
| { |
| platform_driver_unregister(&td_driver); |
| } |
| module_exit(td_exit); |
| |
| MODULE_LICENSE("GPL v2"); |
| MODULE_DESCRIPTION("Timberdale DMA controller driver"); |
| MODULE_AUTHOR("Pelagicore AB <info@pelagicore.com>"); |
| MODULE_ALIAS("platform:"DRIVER_NAME); |