| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Nicolas Ferre | 5865 | 65.17% | 31 | 36.05% |
| Maxime Ripard | 1599 | 17.77% | 5 | 5.81% |
| Ludovic Desroches | 478 | 5.31% | 4 | 4.65% |
| Torsten Fleischer | 460 | 5.11% | 2 | 2.33% |
| Elen Song | 206 | 2.29% | 1 | 1.16% |
| Cyrille Pitchen | 111 | 1.23% | 1 | 1.16% |
| Dan J Williams | 40 | 0.44% | 3 | 3.49% |
| Richard Genoud | 32 | 0.36% | 2 | 2.33% |
| Russell King | 25 | 0.28% | 6 | 6.98% |
| Linus Walleij | 25 | 0.28% | 3 | 3.49% |
| Maninder Singh | 22 | 0.24% | 1 | 1.16% |
| Vinod Koul | 20 | 0.22% | 4 | 4.65% |
| Boris Brezillon | 17 | 0.19% | 1 | 1.16% |
| Andy Shevchenko | 14 | 0.16% | 1 | 1.16% |
| Arnd Bergmann | 12 | 0.13% | 1 | 1.16% |
| Nikolaus Voss | 10 | 0.11% | 1 | 1.16% |
| Dave Jiang | 9 | 0.10% | 2 | 2.33% |
| Linus Torvalds | 7 | 0.08% | 1 | 1.16% |
| Yong Wang | 7 | 0.08% | 1 | 1.16% |
| Gustavo A. R. Silva | 6 | 0.07% | 1 | 1.16% |
| Wolfram Sang | 6 | 0.07% | 1 | 1.16% |
| Alex Bounine | 6 | 0.07% | 1 | 1.16% |
| H Hartley Sweeten | 6 | 0.07% | 1 | 1.16% |
| Uwe Kleine-König | 3 | 0.03% | 2 | 2.33% |
| Tejun Heo | 3 | 0.03% | 1 | 1.16% |
| Peter Ujfalusi | 3 | 0.03% | 1 | 1.16% |
| Masanari Iida | 2 | 0.02% | 1 | 1.16% |
| Eric Xu | 1 | 0.01% | 1 | 1.16% |
| Alexey Dobriyan | 1 | 0.01% | 1 | 1.16% |
| Atsushi Nemoto | 1 | 0.01% | 1 | 1.16% |
| Laurent Pinchart | 1 | 0.01% | 1 | 1.16% |
| André Goddard Rosa | 1 | 0.01% | 1 | 1.16% |
| Barry Song | 1 | 0.01% | 1 | 1.16% |
| Total | 9000 | 86 |
/* * Driver for the Atmel AHB DMA Controller (aka HDMA or DMAC on AT91 systems) * * Copyright (C) 2008 Atmel Corporation * * 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 supports the Atmel AHB DMA Controller found in several Atmel SoCs. * The only Atmel DMA Controller that is not covered by this driver is the one * found on AT91SAM9263. */ #include <dt-bindings/dma/at91.h> #include <linux/clk.h> #include <linux/dmaengine.h> #include <linux/dma-mapping.h> #include <linux/dmapool.h> #include <linux/interrupt.h> #include <linux/module.h> #include <linux/platform_device.h> #include <linux/slab.h> #include <linux/of.h> #include <linux/of_device.h> #include <linux/of_dma.h> #include "at_hdmac_regs.h" #include "dmaengine.h" /* * Glossary * -------- * * at_hdmac : Name of the ATmel AHB DMA Controller * at_dma_ / atdma : ATmel DMA controller entity related * atc_ / atchan : ATmel DMA Channel entity related */ #define ATC_DEFAULT_CFG (ATC_FIFOCFG_HALFFIFO) #define ATC_DEFAULT_CTRLB (ATC_SIF(AT_DMA_MEM_IF) \ |ATC_DIF(AT_DMA_MEM_IF)) #define ATC_DMA_BUSWIDTHS\ (BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) |\ BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |\ BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |\ BIT(DMA_SLAVE_BUSWIDTH_4_BYTES)) #define ATC_MAX_DSCR_TRIALS 10 /* * Initial number of descriptors to allocate for each channel. This could * be increased during dma usage. */ static unsigned int init_nr_desc_per_channel = 64; module_param(init_nr_desc_per_channel, uint, 0644); MODULE_PARM_DESC(init_nr_desc_per_channel, "initial descriptors per channel (default: 64)"); /* prototypes */ static dma_cookie_t atc_tx_submit(struct dma_async_tx_descriptor *tx); static void atc_issue_pending(struct dma_chan *chan); /*----------------------------------------------------------------------*/ static inline unsigned int atc_get_xfer_width(dma_addr_t src, dma_addr_t dst, size_t len) { unsigned int width; if (!((src | dst | len) & 3)) width = 2; else if (!((src | dst | len) & 1)) width = 1; else width = 0; return width; } static struct at_desc *atc_first_active(struct at_dma_chan *atchan) { return list_first_entry(&atchan->active_list, struct at_desc, desc_node); } static struct at_desc *atc_first_queued(struct at_dma_chan *atchan) { return list_first_entry(&atchan->queue, struct at_desc, desc_node); } /** * atc_alloc_descriptor - allocate and return an initialized descriptor * @chan: the channel to allocate descriptors for * @gfp_flags: GFP allocation flags * * Note: The ack-bit is positioned in the descriptor flag at creation time * to make initial allocation more convenient. This bit will be cleared * and control will be given to client at usage time (during * preparation functions). */ static struct at_desc *atc_alloc_descriptor(struct dma_chan *chan, gfp_t gfp_flags) { struct at_desc *desc = NULL; struct at_dma *atdma = to_at_dma(chan->device); dma_addr_t phys; desc = dma_pool_zalloc(atdma->dma_desc_pool, gfp_flags, &phys); if (desc) { INIT_LIST_HEAD(&desc->tx_list); dma_async_tx_descriptor_init(&desc->txd, chan); /* txd.flags will be overwritten in prep functions */ desc->txd.flags = DMA_CTRL_ACK; desc->txd.tx_submit = atc_tx_submit; desc->txd.phys = phys; } return desc; } /** * atc_desc_get - get an unused descriptor from free_list * @atchan: channel we want a new descriptor for */ static struct at_desc *atc_desc_get(struct at_dma_chan *atchan) { struct at_desc *desc, *_desc; struct at_desc *ret = NULL; unsigned long flags; unsigned int i = 0; LIST_HEAD(tmp_list); spin_lock_irqsave(&atchan->lock, flags); list_for_each_entry_safe(desc, _desc, &atchan->free_list, desc_node) { i++; if (async_tx_test_ack(&desc->txd)) { list_del(&desc->desc_node); ret = desc; break; } dev_dbg(chan2dev(&atchan->chan_common), "desc %p not ACKed\n", desc); } spin_unlock_irqrestore(&atchan->lock, flags); dev_vdbg(chan2dev(&atchan->chan_common), "scanned %u descriptors on freelist\n", i); /* no more descriptor available in initial pool: create one more */ if (!ret) { ret = atc_alloc_descriptor(&atchan->chan_common, GFP_ATOMIC); if (ret) { spin_lock_irqsave(&atchan->lock, flags); atchan->descs_allocated++; spin_unlock_irqrestore(&atchan->lock, flags); } else { dev_err(chan2dev(&atchan->chan_common), "not enough descriptors available\n"); } } return ret; } /** * atc_desc_put - move a descriptor, including any children, to the free list * @atchan: channel we work on * @desc: descriptor, at the head of a chain, to move to free list */ static void atc_desc_put(struct at_dma_chan *atchan, struct at_desc *desc) { if (desc) { struct at_desc *child; unsigned long flags; spin_lock_irqsave(&atchan->lock, flags); list_for_each_entry(child, &desc->tx_list, desc_node) dev_vdbg(chan2dev(&atchan->chan_common), "moving child desc %p to freelist\n", child); list_splice_init(&desc->tx_list, &atchan->free_list); dev_vdbg(chan2dev(&atchan->chan_common), "moving desc %p to freelist\n", desc); list_add(&desc->desc_node, &atchan->free_list); spin_unlock_irqrestore(&atchan->lock, flags); } } /** * atc_desc_chain - build chain adding a descriptor * @first: address of first descriptor of the chain * @prev: address of previous descriptor of the chain * @desc: descriptor to queue * * Called from prep_* functions */ static void atc_desc_chain(struct at_desc **first, struct at_desc **prev, struct at_desc *desc) { if (!(*first)) { *first = desc; } else { /* inform the HW lli about chaining */ (*prev)->lli.dscr = desc->txd.phys; /* insert the link descriptor to the LD ring */ list_add_tail(&desc->desc_node, &(*first)->tx_list); } *prev = desc; } /** * atc_dostart - starts the DMA engine for real * @atchan: the channel we want to start * @first: first descriptor in the list we want to begin with * * Called with atchan->lock held and bh disabled */ static void atc_dostart(struct at_dma_chan *atchan, struct at_desc *first) { struct at_dma *atdma = to_at_dma(atchan->chan_common.device); /* ASSERT: channel is idle */ if (atc_chan_is_enabled(atchan)) { dev_err(chan2dev(&atchan->chan_common), "BUG: Attempted to start non-idle channel\n"); dev_err(chan2dev(&atchan->chan_common), " channel: s0x%x d0x%x ctrl0x%x:0x%x l0x%x\n", channel_readl(atchan, SADDR), channel_readl(atchan, DADDR), channel_readl(atchan, CTRLA), channel_readl(atchan, CTRLB), channel_readl(atchan, DSCR)); /* The tasklet will hopefully advance the queue... */ return; } vdbg_dump_regs(atchan); channel_writel(atchan, SADDR, 0); channel_writel(atchan, DADDR, 0); channel_writel(atchan, CTRLA, 0); channel_writel(atchan, CTRLB, 0); channel_writel(atchan, DSCR, first->txd.phys); channel_writel(atchan, SPIP, ATC_SPIP_HOLE(first->src_hole) | ATC_SPIP_BOUNDARY(first->boundary)); channel_writel(atchan, DPIP, ATC_DPIP_HOLE(first->dst_hole) | ATC_DPIP_BOUNDARY(first->boundary)); dma_writel(atdma, CHER, atchan->mask); vdbg_dump_regs(atchan); } /* * atc_get_desc_by_cookie - get the descriptor of a cookie * @atchan: the DMA channel * @cookie: the cookie to get the descriptor for */ static struct at_desc *atc_get_desc_by_cookie(struct at_dma_chan *atchan, dma_cookie_t cookie) { struct at_desc *desc, *_desc; list_for_each_entry_safe(desc, _desc, &atchan->queue, desc_node) { if (desc->txd.cookie == cookie) return desc; } list_for_each_entry_safe(desc, _desc, &atchan->active_list, desc_node) { if (desc->txd.cookie == cookie) return desc; } return NULL; } /** * atc_calc_bytes_left - calculates the number of bytes left according to the * value read from CTRLA. * * @current_len: the number of bytes left before reading CTRLA * @ctrla: the value of CTRLA */ static inline int atc_calc_bytes_left(int current_len, u32 ctrla) { u32 btsize = (ctrla & ATC_BTSIZE_MAX); u32 src_width = ATC_REG_TO_SRC_WIDTH(ctrla); /* * According to the datasheet, when reading the Control A Register * (ctrla), the Buffer Transfer Size (btsize) bitfield refers to the * number of transfers completed on the Source Interface. * So btsize is always a number of source width transfers. */ return current_len - (btsize << src_width); } /** * atc_get_bytes_left - get the number of bytes residue for a cookie * @chan: DMA channel * @cookie: transaction identifier to check status of */ static int atc_get_bytes_left(struct dma_chan *chan, dma_cookie_t cookie) { struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_desc *desc_first = atc_first_active(atchan); struct at_desc *desc; int ret; u32 ctrla, dscr, trials; /* * If the cookie doesn't match to the currently running transfer then * we can return the total length of the associated DMA transfer, * because it is still queued. */ desc = atc_get_desc_by_cookie(atchan, cookie); if (desc == NULL) return -EINVAL; else if (desc != desc_first) return desc->total_len; /* cookie matches to the currently running transfer */ ret = desc_first->total_len; if (desc_first->lli.dscr) { /* hardware linked list transfer */ /* * Calculate the residue by removing the length of the child * descriptors already transferred from the total length. * To get the current child descriptor we can use the value of * the channel's DSCR register and compare it against the value * of the hardware linked list structure of each child * descriptor. * * The CTRLA register provides us with the amount of data * already read from the source for the current child * descriptor. So we can compute a more accurate residue by also * removing the number of bytes corresponding to this amount of * data. * * However, the DSCR and CTRLA registers cannot be read both * atomically. Hence a race condition may occur: the first read * register may refer to one child descriptor whereas the second * read may refer to a later child descriptor in the list * because of the DMA transfer progression inbetween the two * reads. * * One solution could have been to pause the DMA transfer, read * the DSCR and CTRLA then resume the DMA transfer. Nonetheless, * this approach presents some drawbacks: * - If the DMA transfer is paused, RX overruns or TX underruns * are more likey to occur depending on the system latency. * Taking the USART driver as an example, it uses a cyclic DMA * transfer to read data from the Receive Holding Register * (RHR) to avoid RX overruns since the RHR is not protected * by any FIFO on most Atmel SoCs. So pausing the DMA transfer * to compute the residue would break the USART driver design. * - The atc_pause() function masks interrupts but we'd rather * avoid to do so for system latency purpose. * * Then we'd rather use another solution: the DSCR is read a * first time, the CTRLA is read in turn, next the DSCR is read * a second time. If the two consecutive read values of the DSCR * are the same then we assume both refers to the very same * child descriptor as well as the CTRLA value read inbetween * does. For cyclic tranfers, the assumption is that a full loop * is "not so fast". * If the two DSCR values are different, we read again the CTRLA * then the DSCR till two consecutive read values from DSCR are * equal or till the maxium trials is reach. * This algorithm is very unlikely not to find a stable value for * DSCR. */ dscr = channel_readl(atchan, DSCR); rmb(); /* ensure DSCR is read before CTRLA */ ctrla = channel_readl(atchan, CTRLA); for (trials = 0; trials < ATC_MAX_DSCR_TRIALS; ++trials) { u32 new_dscr; rmb(); /* ensure DSCR is read after CTRLA */ new_dscr = channel_readl(atchan, DSCR); /* * If the DSCR register value has not changed inside the * DMA controller since the previous read, we assume * that both the dscr and ctrla values refers to the * very same descriptor. */ if (likely(new_dscr == dscr)) break; /* * DSCR has changed inside the DMA controller, so the * previouly read value of CTRLA may refer to an already * processed descriptor hence could be outdated. * We need to update ctrla to match the current * descriptor. */ dscr = new_dscr; rmb(); /* ensure DSCR is read before CTRLA */ ctrla = channel_readl(atchan, CTRLA); } if (unlikely(trials >= ATC_MAX_DSCR_TRIALS)) return -ETIMEDOUT; /* for the first descriptor we can be more accurate */ if (desc_first->lli.dscr == dscr) return atc_calc_bytes_left(ret, ctrla); ret -= desc_first->len; list_for_each_entry(desc, &desc_first->tx_list, desc_node) { if (desc->lli.dscr == dscr) break; ret -= desc->len; } /* * For the current descriptor in the chain we can calculate * the remaining bytes using the channel's register. */ ret = atc_calc_bytes_left(ret, ctrla); } else { /* single transfer */ ctrla = channel_readl(atchan, CTRLA); ret = atc_calc_bytes_left(ret, ctrla); } return ret; } /** * atc_chain_complete - finish work for one transaction chain * @atchan: channel we work on * @desc: descriptor at the head of the chain we want do complete * * Called with atchan->lock held and bh disabled */ static void atc_chain_complete(struct at_dma_chan *atchan, struct at_desc *desc) { struct dma_async_tx_descriptor *txd = &desc->txd; struct at_dma *atdma = to_at_dma(atchan->chan_common.device); dev_vdbg(chan2dev(&atchan->chan_common), "descriptor %u complete\n", txd->cookie); /* mark the descriptor as complete for non cyclic cases only */ if (!atc_chan_is_cyclic(atchan)) dma_cookie_complete(txd); /* If the transfer was a memset, free our temporary buffer */ if (desc->memset_buffer) { dma_pool_free(atdma->memset_pool, desc->memset_vaddr, desc->memset_paddr); desc->memset_buffer = false; } /* move children to free_list */ list_splice_init(&desc->tx_list, &atchan->free_list); /* move myself to free_list */ list_move(&desc->desc_node, &atchan->free_list); dma_descriptor_unmap(txd); /* for cyclic transfers, * no need to replay callback function while stopping */ if (!atc_chan_is_cyclic(atchan)) { /* * The API requires that no submissions are done from a * callback, so we don't need to drop the lock here */ dmaengine_desc_get_callback_invoke(txd, NULL); } dma_run_dependencies(txd); } /** * atc_complete_all - finish work for all transactions * @atchan: channel to complete transactions for * * Eventually submit queued descriptors if any * * Assume channel is idle while calling this function * Called with atchan->lock held and bh disabled */ static void atc_complete_all(struct at_dma_chan *atchan) { struct at_desc *desc, *_desc; LIST_HEAD(list); dev_vdbg(chan2dev(&atchan->chan_common), "complete all\n"); /* * Submit queued descriptors ASAP, i.e. before we go through * the completed ones. */ if (!list_empty(&atchan->queue)) atc_dostart(atchan, atc_first_queued(atchan)); /* empty active_list now it is completed */ list_splice_init(&atchan->active_list, &list); /* empty queue list by moving descriptors (if any) to active_list */ list_splice_init(&atchan->queue, &atchan->active_list); list_for_each_entry_safe(desc, _desc, &list, desc_node) atc_chain_complete(atchan, desc); } /** * atc_advance_work - at the end of a transaction, move forward * @atchan: channel where the transaction ended * * Called with atchan->lock held and bh disabled */ static void atc_advance_work(struct at_dma_chan *atchan) { dev_vdbg(chan2dev(&atchan->chan_common), "advance_work\n"); if (atc_chan_is_enabled(atchan)) return; if (list_empty(&atchan->active_list) || list_is_singular(&atchan->active_list)) { atc_complete_all(atchan); } else { atc_chain_complete(atchan, atc_first_active(atchan)); /* advance work */ atc_dostart(atchan, atc_first_active(atchan)); } } /** * atc_handle_error - handle errors reported by DMA controller * @atchan: channel where error occurs * * Called with atchan->lock held and bh disabled */ static void atc_handle_error(struct at_dma_chan *atchan) { struct at_desc *bad_desc; struct at_desc *child; /* * The descriptor currently at the head of the active list is * broked. Since we don't have any way to report errors, we'll * just have to scream loudly and try to carry on. */ bad_desc = atc_first_active(atchan); list_del_init(&bad_desc->desc_node); /* As we are stopped, take advantage to push queued descriptors * in active_list */ list_splice_init(&atchan->queue, atchan->active_list.prev); /* Try to restart the controller */ if (!list_empty(&atchan->active_list)) atc_dostart(atchan, atc_first_active(atchan)); /* * KERN_CRITICAL may seem harsh, but since this only happens * when someone submits a bad physical address in a * descriptor, we should consider ourselves lucky that the * controller flagged an error instead of scribbling over * random memory locations. */ dev_crit(chan2dev(&atchan->chan_common), "Bad descriptor submitted for DMA!\n"); dev_crit(chan2dev(&atchan->chan_common), " cookie: %d\n", bad_desc->txd.cookie); atc_dump_lli(atchan, &bad_desc->lli); list_for_each_entry(child, &bad_desc->tx_list, desc_node) atc_dump_lli(atchan, &child->lli); /* Pretend the descriptor completed successfully */ atc_chain_complete(atchan, bad_desc); } /** * atc_handle_cyclic - at the end of a period, run callback function * @atchan: channel used for cyclic operations * * Called with atchan->lock held and bh disabled */ static void atc_handle_cyclic(struct at_dma_chan *atchan) { struct at_desc *first = atc_first_active(atchan); struct dma_async_tx_descriptor *txd = &first->txd; dev_vdbg(chan2dev(&atchan->chan_common), "new cyclic period llp 0x%08x\n", channel_readl(atchan, DSCR)); dmaengine_desc_get_callback_invoke(txd, NULL); } /*-- IRQ & Tasklet ---------------------------------------------------*/ static void atc_tasklet(unsigned long data) { struct at_dma_chan *atchan = (struct at_dma_chan *)data; unsigned long flags; spin_lock_irqsave(&atchan->lock, flags); if (test_and_clear_bit(ATC_IS_ERROR, &atchan->status)) atc_handle_error(atchan); else if (atc_chan_is_cyclic(atchan)) atc_handle_cyclic(atchan); else atc_advance_work(atchan); spin_unlock_irqrestore(&atchan->lock, flags); } static irqreturn_t at_dma_interrupt(int irq, void *dev_id) { struct at_dma *atdma = (struct at_dma *)dev_id; struct at_dma_chan *atchan; int i; u32 status, pending, imr; int ret = IRQ_NONE; do { imr = dma_readl(atdma, EBCIMR); status = dma_readl(atdma, EBCISR); pending = status & imr; if (!pending) break; dev_vdbg(atdma->dma_common.dev, "interrupt: status = 0x%08x, 0x%08x, 0x%08x\n", status, imr, pending); for (i = 0; i < atdma->dma_common.chancnt; i++) { atchan = &atdma->chan[i]; if (pending & (AT_DMA_BTC(i) | AT_DMA_ERR(i))) { if (pending & AT_DMA_ERR(i)) { /* Disable channel on AHB error */ dma_writel(atdma, CHDR, AT_DMA_RES(i) | atchan->mask); /* Give information to tasklet */ set_bit(ATC_IS_ERROR, &atchan->status); } tasklet_schedule(&atchan->tasklet); ret = IRQ_HANDLED; } } } while (pending); return ret; } /*-- DMA Engine API --------------------------------------------------*/ /** * atc_tx_submit - set the prepared descriptor(s) to be executed by the engine * @desc: descriptor at the head of the transaction chain * * Queue chain if DMA engine is working already * * Cookie increment and adding to active_list or queue must be atomic */ static dma_cookie_t atc_tx_submit(struct dma_async_tx_descriptor *tx) { struct at_desc *desc = txd_to_at_desc(tx); struct at_dma_chan *atchan = to_at_dma_chan(tx->chan); dma_cookie_t cookie; unsigned long flags; spin_lock_irqsave(&atchan->lock, flags); cookie = dma_cookie_assign(tx); if (list_empty(&atchan->active_list)) { dev_vdbg(chan2dev(tx->chan), "tx_submit: started %u\n", desc->txd.cookie); atc_dostart(atchan, desc); list_add_tail(&desc->desc_node, &atchan->active_list); } else { dev_vdbg(chan2dev(tx->chan), "tx_submit: queued %u\n", desc->txd.cookie); list_add_tail(&desc->desc_node, &atchan->queue); } spin_unlock_irqrestore(&atchan->lock, flags); return cookie; } /** * atc_prep_dma_interleaved - prepare memory to memory interleaved operation * @chan: the channel to prepare operation on * @xt: Interleaved transfer template * @flags: tx descriptor status flags */ static struct dma_async_tx_descriptor * atc_prep_dma_interleaved(struct dma_chan *chan, struct dma_interleaved_template *xt, unsigned long flags) { struct at_dma_chan *atchan = to_at_dma_chan(chan); struct data_chunk *first; struct at_desc *desc = NULL; size_t xfer_count; unsigned int dwidth; u32 ctrla; u32 ctrlb; size_t len = 0; int i; if (unlikely(!xt || xt->numf != 1 || !xt->frame_size)) return NULL; first = xt->sgl; dev_info(chan2dev(chan), "%s: src=%pad, dest=%pad, numf=%d, frame_size=%d, flags=0x%lx\n", __func__, &xt->src_start, &xt->dst_start, xt->numf, xt->frame_size, flags); /* * The controller can only "skip" X bytes every Y bytes, so we * need to make sure we are given a template that fit that * description, ie a template with chunks that always have the * same size, with the same ICGs. */ for (i = 0; i < xt->frame_size; i++) { struct data_chunk *chunk = xt->sgl + i; if ((chunk->size != xt->sgl->size) || (dmaengine_get_dst_icg(xt, chunk) != dmaengine_get_dst_icg(xt, first)) || (dmaengine_get_src_icg(xt, chunk) != dmaengine_get_src_icg(xt, first))) { dev_err(chan2dev(chan), "%s: the controller can transfer only identical chunks\n", __func__); return NULL; } len += chunk->size; } dwidth = atc_get_xfer_width(xt->src_start, xt->dst_start, len); xfer_count = len >> dwidth; if (xfer_count > ATC_BTSIZE_MAX) { dev_err(chan2dev(chan), "%s: buffer is too big\n", __func__); return NULL; } ctrla = ATC_SRC_WIDTH(dwidth) | ATC_DST_WIDTH(dwidth); ctrlb = ATC_DEFAULT_CTRLB | ATC_IEN | ATC_SRC_ADDR_MODE_INCR | ATC_DST_ADDR_MODE_INCR | ATC_SRC_PIP | ATC_DST_PIP | ATC_FC_MEM2MEM; /* create the transfer */ desc = atc_desc_get(atchan); if (!desc) { dev_err(chan2dev(chan), "%s: couldn't allocate our descriptor\n", __func__); return NULL; } desc->lli.saddr = xt->src_start; desc->lli.daddr = xt->dst_start; desc->lli.ctrla = ctrla | xfer_count; desc->lli.ctrlb = ctrlb; desc->boundary = first->size >> dwidth; desc->dst_hole = (dmaengine_get_dst_icg(xt, first) >> dwidth) + 1; desc->src_hole = (dmaengine_get_src_icg(xt, first) >> dwidth) + 1; desc->txd.cookie = -EBUSY; desc->total_len = desc->len = len; /* set end-of-link to the last link descriptor of list*/ set_desc_eol(desc); desc->txd.flags = flags; /* client is in control of this ack */ return &desc->txd; } /** * atc_prep_dma_memcpy - prepare a memcpy operation * @chan: the channel to prepare operation on * @dest: operation virtual destination address * @src: operation virtual source address * @len: operation length * @flags: tx descriptor status flags */ static struct dma_async_tx_descriptor * atc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, size_t len, unsigned long flags) { struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_desc *desc = NULL; struct at_desc *first = NULL; struct at_desc *prev = NULL; size_t xfer_count; size_t offset; unsigned int src_width; unsigned int dst_width; u32 ctrla; u32 ctrlb; dev_vdbg(chan2dev(chan), "prep_dma_memcpy: d%pad s%pad l0x%zx f0x%lx\n", &dest, &src, len, flags); if (unlikely(!len)) { dev_dbg(chan2dev(chan), "prep_dma_memcpy: length is zero!\n"); return NULL; } ctrlb = ATC_DEFAULT_CTRLB | ATC_IEN | ATC_SRC_ADDR_MODE_INCR | ATC_DST_ADDR_MODE_INCR | ATC_FC_MEM2MEM; /* * We can be a lot more clever here, but this should take care * of the most common optimization. */ src_width = dst_width = atc_get_xfer_width(src, dest, len); ctrla = ATC_SRC_WIDTH(src_width) | ATC_DST_WIDTH(dst_width); for (offset = 0; offset < len; offset += xfer_count << src_width) { xfer_count = min_t(size_t, (len - offset) >> src_width, ATC_BTSIZE_MAX); desc = atc_desc_get(atchan); if (!desc) goto err_desc_get; desc->lli.saddr = src + offset; desc->lli.daddr = dest + offset; desc->lli.ctrla = ctrla | xfer_count; desc->lli.ctrlb = ctrlb; desc->txd.cookie = 0; desc->len = xfer_count << src_width; atc_desc_chain(&first, &prev, desc); } /* First descriptor of the chain embedds additional information */ first->txd.cookie = -EBUSY; first->total_len = len; /* set end-of-link to the last link descriptor of list*/ set_desc_eol(desc); first->txd.flags = flags; /* client is in control of this ack */ return &first->txd; err_desc_get: atc_desc_put(atchan, first); return NULL; } static struct at_desc *atc_create_memset_desc(struct dma_chan *chan, dma_addr_t psrc, dma_addr_t pdst, size_t len) { struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_desc *desc; size_t xfer_count; u32 ctrla = ATC_SRC_WIDTH(2) | ATC_DST_WIDTH(2); u32 ctrlb = ATC_DEFAULT_CTRLB | ATC_IEN | ATC_SRC_ADDR_MODE_FIXED | ATC_DST_ADDR_MODE_INCR | ATC_FC_MEM2MEM; xfer_count = len >> 2; if (xfer_count > ATC_BTSIZE_MAX) { dev_err(chan2dev(chan), "%s: buffer is too big\n", __func__); return NULL; } desc = atc_desc_get(atchan); if (!desc) { dev_err(chan2dev(chan), "%s: can't get a descriptor\n", __func__); return NULL; } desc->lli.saddr = psrc; desc->lli.daddr = pdst; desc->lli.ctrla = ctrla | xfer_count; desc->lli.ctrlb = ctrlb; desc->txd.cookie = 0; desc->len = len; return desc; } /** * atc_prep_dma_memset - prepare a memcpy operation * @chan: the channel to prepare operation on * @dest: operation virtual destination address * @value: value to set memory buffer to * @len: operation length * @flags: tx descriptor status flags */ static struct dma_async_tx_descriptor * atc_prep_dma_memset(struct dma_chan *chan, dma_addr_t dest, int value, size_t len, unsigned long flags) { struct at_dma *atdma = to_at_dma(chan->device); struct at_desc *desc; void __iomem *vaddr; dma_addr_t paddr; dev_vdbg(chan2dev(chan), "%s: d%pad v0x%x l0x%zx f0x%lx\n", __func__, &dest, value, len, flags); if (unlikely(!len)) { dev_dbg(chan2dev(chan), "%s: length is zero!\n", __func__); return NULL; } if (!is_dma_fill_aligned(chan->device, dest, 0, len)) { dev_dbg(chan2dev(chan), "%s: buffer is not aligned\n", __func__); return NULL; } vaddr = dma_pool_alloc(atdma->memset_pool, GFP_ATOMIC, &paddr); if (!vaddr) { dev_err(chan2dev(chan), "%s: couldn't allocate buffer\n", __func__); return NULL; } *(u32*)vaddr = value; desc = atc_create_memset_desc(chan, paddr, dest, len); if (!desc) { dev_err(chan2dev(chan), "%s: couldn't get a descriptor\n", __func__); goto err_free_buffer; } desc->memset_paddr = paddr; desc->memset_vaddr = vaddr; desc->memset_buffer = true; desc->txd.cookie = -EBUSY; desc->total_len = len; /* set end-of-link on the descriptor */ set_desc_eol(desc); desc->txd.flags = flags; return &desc->txd; err_free_buffer: dma_pool_free(atdma->memset_pool, vaddr, paddr); return NULL; } static struct dma_async_tx_descriptor * atc_prep_dma_memset_sg(struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len, int value, unsigned long flags) { struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_dma *atdma = to_at_dma(chan->device); struct at_desc *desc = NULL, *first = NULL, *prev = NULL; struct scatterlist *sg; void __iomem *vaddr; dma_addr_t paddr; size_t total_len = 0; int i; dev_vdbg(chan2dev(chan), "%s: v0x%x l0x%zx f0x%lx\n", __func__, value, sg_len, flags); if (unlikely(!sgl || !sg_len)) { dev_dbg(chan2dev(chan), "%s: scatterlist is empty!\n", __func__); return NULL; } vaddr = dma_pool_alloc(atdma->memset_pool, GFP_ATOMIC, &paddr); if (!vaddr) { dev_err(chan2dev(chan), "%s: couldn't allocate buffer\n", __func__); return NULL; } *(u32*)vaddr = value; for_each_sg(sgl, sg, sg_len, i) { dma_addr_t dest = sg_dma_address(sg); size_t len = sg_dma_len(sg); dev_vdbg(chan2dev(chan), "%s: d%pad, l0x%zx\n", __func__, &dest, len); if (!is_dma_fill_aligned(chan->device, dest, 0, len)) { dev_err(chan2dev(chan), "%s: buffer is not aligned\n", __func__); goto err_put_desc; } desc = atc_create_memset_desc(chan, paddr, dest, len); if (!desc) goto err_put_desc; atc_desc_chain(&first, &prev, desc); total_len += len; } /* * Only set the buffer pointers on the last descriptor to * avoid free'ing while we have our transfer still going */ desc->memset_paddr = paddr; desc->memset_vaddr = vaddr; desc->memset_buffer = true; first->txd.cookie = -EBUSY; first->total_len = total_len; /* set end-of-link on the descriptor */ set_desc_eol(desc); first->txd.flags = flags; return &first->txd; err_put_desc: atc_desc_put(atchan, first); return NULL; } /** * atc_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction * @chan: DMA channel * @sgl: scatterlist to transfer to/from * @sg_len: number of entries in @scatterlist * @direction: DMA direction * @flags: tx descriptor status flags * @context: transaction context (ignored) */ static struct dma_async_tx_descriptor * atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len, enum dma_transfer_direction direction, unsigned long flags, void *context) { struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_dma_slave *atslave = chan->private; struct dma_slave_config *sconfig = &atchan->dma_sconfig; struct at_desc *first = NULL; struct at_desc *prev = NULL; u32 ctrla; u32 ctrlb; dma_addr_t reg; unsigned int reg_width; unsigned int mem_width; unsigned int i; struct scatterlist *sg; size_t total_len = 0; dev_vdbg(chan2dev(chan), "prep_slave_sg (%d): %s f0x%lx\n", sg_len, direction == DMA_MEM_TO_DEV ? "TO DEVICE" : "FROM DEVICE", flags); if (unlikely(!atslave || !sg_len)) { dev_dbg(chan2dev(chan), "prep_slave_sg: sg length is zero!\n"); return NULL; } ctrla = ATC_SCSIZE(sconfig->src_maxburst) | ATC_DCSIZE(sconfig->dst_maxburst); ctrlb = ATC_IEN; switch (direction) { case DMA_MEM_TO_DEV: reg_width = convert_buswidth(sconfig->dst_addr_width); ctrla |= ATC_DST_WIDTH(reg_width); ctrlb |= ATC_DST_ADDR_MODE_FIXED | ATC_SRC_ADDR_MODE_INCR | ATC_FC_MEM2PER | ATC_SIF(atchan->mem_if) | ATC_DIF(atchan->per_if); reg = sconfig->dst_addr; for_each_sg(sgl, sg, sg_len, i) { struct at_desc *desc; u32 len; u32 mem; desc = atc_desc_get(atchan); if (!desc) goto err_desc_get; mem = sg_dma_address(sg); len = sg_dma_len(sg); if (unlikely(!len)) { dev_dbg(chan2dev(chan), "prep_slave_sg: sg(%d) data length is zero\n", i); goto err; } mem_width = 2; if (unlikely(mem & 3 || len & 3)) mem_width = 0; desc->lli.saddr = mem; desc->lli.daddr = reg; desc->lli.ctrla = ctrla | ATC_SRC_WIDTH(mem_width) | len >> mem_width; desc->lli.ctrlb = ctrlb; desc->len = len; atc_desc_chain(&first, &prev, desc); total_len += len; } break; case DMA_DEV_TO_MEM: reg_width = convert_buswidth(sconfig->src_addr_width); ctrla |= ATC_SRC_WIDTH(reg_width); ctrlb |= ATC_DST_ADDR_MODE_INCR | ATC_SRC_ADDR_MODE_FIXED | ATC_FC_PER2MEM | ATC_SIF(atchan->per_if) | ATC_DIF(atchan->mem_if); reg = sconfig->src_addr; for_each_sg(sgl, sg, sg_len, i) { struct at_desc *desc; u32 len; u32 mem; desc = atc_desc_get(atchan); if (!desc) goto err_desc_get; mem = sg_dma_address(sg); len = sg_dma_len(sg); if (unlikely(!len)) { dev_dbg(chan2dev(chan), "prep_slave_sg: sg(%d) data length is zero\n", i); goto err; } mem_width = 2; if (unlikely(mem & 3 || len & 3)) mem_width = 0; desc->lli.saddr = reg; desc->lli.daddr = mem; desc->lli.ctrla = ctrla | ATC_DST_WIDTH(mem_width) | len >> reg_width; desc->lli.ctrlb = ctrlb; desc->len = len; atc_desc_chain(&first, &prev, desc); total_len += len; } break; default: return NULL; } /* set end-of-link to the last link descriptor of list*/ set_desc_eol(prev); /* First descriptor of the chain embedds additional information */ first->txd.cookie = -EBUSY; first->total_len = total_len; /* first link descriptor of list is responsible of flags */ first->txd.flags = flags; /* client is in control of this ack */ return &first->txd; err_desc_get: dev_err(chan2dev(chan), "not enough descriptors available\n"); err: atc_desc_put(atchan, first); return NULL; } /** * atc_dma_cyclic_check_values * Check for too big/unaligned periods and unaligned DMA buffer */ static int atc_dma_cyclic_check_values(unsigned int reg_width, dma_addr_t buf_addr, size_t period_len) { if (period_len > (ATC_BTSIZE_MAX << reg_width)) goto err_out; if (unlikely(period_len & ((1 << reg_width) - 1))) goto err_out; if (unlikely(buf_addr & ((1 << reg_width) - 1))) goto err_out; return 0; err_out: return -EINVAL; } /** * atc_dma_cyclic_fill_desc - Fill one period descriptor */ static int atc_dma_cyclic_fill_desc(struct dma_chan *chan, struct at_desc *desc, unsigned int period_index, dma_addr_t buf_addr, unsigned int reg_width, size_t period_len, enum dma_transfer_direction direction) { struct at_dma_chan *atchan = to_at_dma_chan(chan); struct dma_slave_config *sconfig = &atchan->dma_sconfig; u32 ctrla; /* prepare common CRTLA value */ ctrla = ATC_SCSIZE(sconfig->src_maxburst) | ATC_DCSIZE(sconfig->dst_maxburst) | ATC_DST_WIDTH(reg_width) | ATC_SRC_WIDTH(reg_width) | period_len >> reg_width; switch (direction) { case DMA_MEM_TO_DEV: desc->lli.saddr = buf_addr + (period_len * period_index); desc->lli.daddr = sconfig->dst_addr; desc->lli.ctrla = ctrla; desc->lli.ctrlb = ATC_DST_ADDR_MODE_FIXED | ATC_SRC_ADDR_MODE_INCR | ATC_FC_MEM2PER | ATC_SIF(atchan->mem_if) | ATC_DIF(atchan->per_if); desc->len = period_len; break; case DMA_DEV_TO_MEM: desc->lli.saddr = sconfig->src_addr; desc->lli.daddr = buf_addr + (period_len * period_index); desc->lli.ctrla = ctrla; desc->lli.ctrlb = ATC_DST_ADDR_MODE_INCR | ATC_SRC_ADDR_MODE_FIXED | ATC_FC_PER2MEM | ATC_SIF(atchan->per_if) | ATC_DIF(atchan->mem_if); desc->len = period_len; break; default: return -EINVAL; } return 0; } /** * atc_prep_dma_cyclic - prepare the cyclic DMA transfer * @chan: the DMA channel to prepare * @buf_addr: physical DMA address where the buffer starts * @buf_len: total number of bytes for the entire buffer * @period_len: number of bytes for each period * @direction: transfer direction, to or from device * @flags: tx descriptor status flags */ static struct dma_async_tx_descriptor * atc_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len, size_t period_len, enum dma_transfer_direction direction, unsigned long flags) { struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_dma_slave *atslave = chan->private; struct dma_slave_config *sconfig = &atchan->dma_sconfig; struct at_desc *first = NULL; struct at_desc *prev = NULL; unsigned long was_cyclic; unsigned int reg_width; unsigned int periods = buf_len / period_len; unsigned int i; dev_vdbg(chan2dev(chan), "prep_dma_cyclic: %s buf@%pad - %d (%d/%d)\n", direction == DMA_MEM_TO_DEV ? "TO DEVICE" : "FROM DEVICE", &buf_addr, periods, buf_len, period_len); if (unlikely(!atslave || !buf_len || !period_len)) { dev_dbg(chan2dev(chan), "prep_dma_cyclic: length is zero!\n"); return NULL; } was_cyclic = test_and_set_bit(ATC_IS_CYCLIC, &atchan->status); if (was_cyclic) { dev_dbg(chan2dev(chan), "prep_dma_cyclic: channel in use!\n"); return NULL; } if (unlikely(!is_slave_direction(direction))) goto err_out; if (direction == DMA_MEM_TO_DEV) reg_width = convert_buswidth(sconfig->dst_addr_width); else reg_width = convert_buswidth(sconfig->src_addr_width); /* Check for too big/unaligned periods and unaligned DMA buffer */ if (atc_dma_cyclic_check_values(reg_width, buf_addr, period_len)) goto err_out; /* build cyclic linked list */ for (i = 0; i < periods; i++) { struct at_desc *desc; desc = atc_desc_get(atchan); if (!desc) goto err_desc_get; if (atc_dma_cyclic_fill_desc(chan, desc, i, buf_addr, reg_width, period_len, direction)) goto err_desc_get; atc_desc_chain(&first, &prev, desc); } /* lets make a cyclic list */ prev->lli.dscr = first->txd.phys; /* First descriptor of the chain embedds additional information */ first->txd.cookie = -EBUSY; first->total_len = buf_len; return &first->txd; err_desc_get: dev_err(chan2dev(chan), "not enough descriptors available\n"); atc_desc_put(atchan, first); err_out: clear_bit(ATC_IS_CYCLIC, &atchan->status); return NULL; } static int atc_config(struct dma_chan *chan, struct dma_slave_config *sconfig) { struct at_dma_chan *atchan = to_at_dma_chan(chan); dev_vdbg(chan2dev(chan), "%s\n", __func__); /* Check if it is chan is configured for slave transfers */ if (!chan->private) return -EINVAL; memcpy(&atchan->dma_sconfig, sconfig, sizeof(*sconfig)); convert_burst(&atchan->dma_sconfig.src_maxburst); convert_burst(&atchan->dma_sconfig.dst_maxburst); return 0; } static int atc_pause(struct dma_chan *chan) { struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_dma *atdma = to_at_dma(chan->device); int chan_id = atchan->chan_common.chan_id; unsigned long flags; LIST_HEAD(list); dev_vdbg(chan2dev(chan), "%s\n", __func__); spin_lock_irqsave(&atchan->lock, flags); dma_writel(atdma, CHER, AT_DMA_SUSP(chan_id)); set_bit(ATC_IS_PAUSED, &atchan->status); spin_unlock_irqrestore(&atchan->lock, flags); return 0; } static int atc_resume(struct dma_chan *chan) { struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_dma *atdma = to_at_dma(chan->device); int chan_id = atchan->chan_common.chan_id; unsigned long flags; LIST_HEAD(list); dev_vdbg(chan2dev(chan), "%s\n", __func__); if (!atc_chan_is_paused(atchan)) return 0; spin_lock_irqsave(&atchan->lock, flags); dma_writel(atdma, CHDR, AT_DMA_RES(chan_id)); clear_bit(ATC_IS_PAUSED, &atchan->status); spin_unlock_irqrestore(&atchan->lock, flags); return 0; } static int atc_terminate_all(struct dma_chan *chan) { struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_dma *atdma = to_at_dma(chan->device); int chan_id = atchan->chan_common.chan_id; struct at_desc *desc, *_desc; unsigned long flags; LIST_HEAD(list); dev_vdbg(chan2dev(chan), "%s\n", __func__); /* * This is only called when something went wrong elsewhere, so * we don't really care about the data. Just disable the * channel. We still have to poll the channel enable bit due * to AHB/HSB limitations. */ spin_lock_irqsave(&atchan->lock, flags); /* disabling channel: must also remove suspend state */ dma_writel(atdma, CHDR, AT_DMA_RES(chan_id) | atchan->mask); /* confirm that this channel is disabled */ while (dma_readl(atdma, CHSR) & atchan->mask) cpu_relax(); /* active_list entries will end up before queued entries */ list_splice_init(&atchan->queue, &list); list_splice_init(&atchan->active_list, &list); /* Flush all pending and queued descriptors */ list_for_each_entry_safe(desc, _desc, &list, desc_node) atc_chain_complete(atchan, desc); clear_bit(ATC_IS_PAUSED, &atchan->status); /* if channel dedicated to cyclic operations, free it */ clear_bit(ATC_IS_CYCLIC, &atchan->status); spin_unlock_irqrestore(&atchan->lock, flags); return 0; } /** * atc_tx_status - poll for transaction completion * @chan: DMA channel * @cookie: transaction identifier to check status of * @txstate: if not %NULL updated with transaction state * * If @txstate is passed in, upon return it reflect the driver * internal state and can be used with dma_async_is_complete() to check * the status of multiple cookies without re-checking hardware state. */ static enum dma_status atc_tx_status(struct dma_chan *chan, dma_cookie_t cookie, struct dma_tx_state *txstate) { struct at_dma_chan *atchan = to_at_dma_chan(chan); unsigned long flags; enum dma_status ret; int bytes = 0; ret = dma_cookie_status(chan, cookie, txstate); if (ret == DMA_COMPLETE) return ret; /* * There's no point calculating the residue if there's * no txstate to store the value. */ if (!txstate) return DMA_ERROR; spin_lock_irqsave(&atchan->lock, flags); /* Get number of bytes left in the active transactions */ bytes = atc_get_bytes_left(chan, cookie); spin_unlock_irqrestore(&atchan->lock, flags); if (unlikely(bytes < 0)) { dev_vdbg(chan2dev(chan), "get residual bytes error\n"); return DMA_ERROR; } else { dma_set_residue(txstate, bytes); } dev_vdbg(chan2dev(chan), "tx_status %d: cookie = %d residue = %d\n", ret, cookie, bytes); return ret; } /** * atc_issue_pending - try to finish work * @chan: target DMA channel */ static void atc_issue_pending(struct dma_chan *chan) { struct at_dma_chan *atchan = to_at_dma_chan(chan); unsigned long flags; dev_vdbg(chan2dev(chan), "issue_pending\n"); /* Not needed for cyclic transfers */ if (atc_chan_is_cyclic(atchan)) return; spin_lock_irqsave(&atchan->lock, flags); atc_advance_work(atchan); spin_unlock_irqrestore(&atchan->lock, flags); } /** * atc_alloc_chan_resources - allocate resources for DMA channel * @chan: allocate descriptor resources for this channel * @client: current client requesting the channel be ready for requests * * return - the number of allocated descriptors */ static int atc_alloc_chan_resources(struct dma_chan *chan) { struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_dma *atdma = to_at_dma(chan->device); struct at_desc *desc; struct at_dma_slave *atslave; unsigned long flags; int i; u32 cfg; LIST_HEAD(tmp_list); dev_vdbg(chan2dev(chan), "alloc_chan_resources\n"); /* ASSERT: channel is idle */ if (atc_chan_is_enabled(atchan)) { dev_dbg(chan2dev(chan), "DMA channel not idle ?\n"); return -EIO; } cfg = ATC_DEFAULT_CFG; atslave = chan->private; if (atslave) { /* * We need controller-specific data to set up slave * transfers. */ BUG_ON(!atslave->dma_dev || atslave->dma_dev != atdma->dma_common.dev); /* if cfg configuration specified take it instead of default */ if (atslave->cfg) cfg = atslave->cfg; } /* have we already been set up? * reconfigure channel but no need to reallocate descriptors */ if (!list_empty(&atchan->free_list)) return atchan->descs_allocated; /* Allocate initial pool of descriptors */ for (i = 0; i < init_nr_desc_per_channel; i++) { desc = atc_alloc_descriptor(chan, GFP_KERNEL); if (!desc) { dev_err(atdma->dma_common.dev, "Only %d initial descriptors\n", i); break; } list_add_tail(&desc->desc_node, &tmp_list); } spin_lock_irqsave(&atchan->lock, flags); atchan->descs_allocated = i; list_splice(&tmp_list, &atchan->free_list); dma_cookie_init(chan); spin_unlock_irqrestore(&atchan->lock, flags); /* channel parameters */ channel_writel(atchan, CFG, cfg); dev_dbg(chan2dev(chan), "alloc_chan_resources: allocated %d descriptors\n", atchan->descs_allocated); return atchan->descs_allocated; } /** * atc_free_chan_resources - free all channel resources * @chan: DMA channel */ static void atc_free_chan_resources(struct dma_chan *chan) { struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_dma *atdma = to_at_dma(chan->device); struct at_desc *desc, *_desc; LIST_HEAD(list); dev_dbg(chan2dev(chan), "free_chan_resources: (descs allocated=%u)\n", atchan->descs_allocated); /* ASSERT: channel is idle */ BUG_ON(!list_empty(&atchan->active_list)); BUG_ON(!list_empty(&atchan->queue)); BUG_ON(atc_chan_is_enabled(atchan)); list_for_each_entry_safe(desc, _desc, &atchan->free_list, desc_node) { dev_vdbg(chan2dev(chan), " freeing descriptor %p\n", desc); list_del(&desc->desc_node); /* free link descriptor */ dma_pool_free(atdma->dma_desc_pool, desc, desc->txd.phys); } list_splice_init(&atchan->free_list, &list); atchan->descs_allocated = 0; atchan->status = 0; /* * Free atslave allocated in at_dma_xlate() */ kfree(chan->private); chan->private = NULL; dev_vdbg(chan2dev(chan), "free_chan_resources: done\n"); } #ifdef CONFIG_OF static bool at_dma_filter(struct dma_chan *chan, void *slave) { struct at_dma_slave *atslave = slave; if (atslave->dma_dev == chan->device->dev) { chan->private = atslave; return true; } else { return false; } } static struct dma_chan *at_dma_xlate(struct of_phandle_args *dma_spec, struct of_dma *of_dma) { struct dma_chan *chan; struct at_dma_chan *atchan; struct at_dma_slave *atslave; dma_cap_mask_t mask; unsigned int per_id; struct platform_device *dmac_pdev; if (dma_spec->args_count != 2) return NULL; dmac_pdev = of_find_device_by_node(dma_spec->np); dma_cap_zero(mask); dma_cap_set(DMA_SLAVE, mask); atslave = kzalloc(sizeof(*atslave), GFP_KERNEL); if (!atslave) return NULL; atslave->cfg = ATC_DST_H2SEL_HW | ATC_SRC_H2SEL_HW; /* * We can fill both SRC_PER and DST_PER, one of these fields will be * ignored depending on DMA transfer direction. */ per_id = dma_spec->args[1] & AT91_DMA_CFG_PER_ID_MASK; atslave->cfg |= ATC_DST_PER_MSB(per_id) | ATC_DST_PER(per_id) | ATC_SRC_PER_MSB(per_id) | ATC_SRC_PER(per_id); /* * We have to translate the value we get from the device tree since * the half FIFO configuration value had to be 0 to keep backward * compatibility. */ switch (dma_spec->args[1] & AT91_DMA_CFG_FIFOCFG_MASK) { case AT91_DMA_CFG_FIFOCFG_ALAP: atslave->cfg |= ATC_FIFOCFG_LARGESTBURST; break; case AT91_DMA_CFG_FIFOCFG_ASAP: atslave->cfg |= ATC_FIFOCFG_ENOUGHSPACE; break; case AT91_DMA_CFG_FIFOCFG_HALF: default: atslave->cfg |= ATC_FIFOCFG_HALFFIFO; } atslave->dma_dev = &dmac_pdev->dev; chan = dma_request_channel(mask, at_dma_filter, atslave); if (!chan) return NULL; atchan = to_at_dma_chan(chan); atchan->per_if = dma_spec->args[0] & 0xff; atchan->mem_if = (dma_spec->args[0] >> 16) & 0xff; return chan; } #else static struct dma_chan *at_dma_xlate(struct of_phandle_args *dma_spec, struct of_dma *of_dma) { return NULL; } #endif /*-- Module Management -----------------------------------------------*/ /* cap_mask is a multi-u32 bitfield, fill it with proper C code. */ static struct at_dma_platform_data at91sam9rl_config = { .nr_channels = 2, }; static struct at_dma_platform_data at91sam9g45_config = { .nr_channels = 8, }; #if defined(CONFIG_OF) static const struct of_device_id atmel_dma_dt_ids[] = { { .compatible = "atmel,at91sam9rl-dma", .data = &at91sam9rl_config, }, { .compatible = "atmel,at91sam9g45-dma", .data = &at91sam9g45_config, }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, atmel_dma_dt_ids); #endif static const struct platform_device_id atdma_devtypes[] = { { .name = "at91sam9rl_dma", .driver_data = (unsigned long) &at91sam9rl_config, }, { .name = "at91sam9g45_dma", .driver_data = (unsigned long) &at91sam9g45_config, }, { /* sentinel */ } }; static inline const struct at_dma_platform_data * __init at_dma_get_driver_data( struct platform_device *pdev) { if (pdev->dev.of_node) { const struct of_device_id *match; match = of_match_node(atmel_dma_dt_ids, pdev->dev.of_node); if (match == NULL) return NULL; return match->data; } return (struct at_dma_platform_data *) platform_get_device_id(pdev)->driver_data; } /** * at_dma_off - disable DMA controller * @atdma: the Atmel HDAMC device */ static void at_dma_off(struct at_dma *atdma) { dma_writel(atdma, EN, 0); /* disable all interrupts */ dma_writel(atdma, EBCIDR, -1L); /* confirm that all channels are disabled */ while (dma_readl(atdma, CHSR) & atdma->all_chan_mask) cpu_relax(); } static int __init at_dma_probe(struct platform_device *pdev) { struct resource *io; struct at_dma *atdma; size_t size; int irq; int err; int i; const struct at_dma_platform_data *plat_dat; /* setup platform data for each SoC */ dma_cap_set(DMA_MEMCPY, at91sam9rl_config.cap_mask); dma_cap_set(DMA_INTERLEAVE, at91sam9g45_config.cap_mask); dma_cap_set(DMA_MEMCPY, at91sam9g45_config.cap_mask); dma_cap_set(DMA_MEMSET, at91sam9g45_config.cap_mask); dma_cap_set(DMA_MEMSET_SG, at91sam9g45_config.cap_mask); dma_cap_set(DMA_PRIVATE, at91sam9g45_config.cap_mask); dma_cap_set(DMA_SLAVE, at91sam9g45_config.cap_mask); /* get DMA parameters from controller type */ plat_dat = at_dma_get_driver_data(pdev); if (!plat_dat) return -ENODEV; io = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!io) return -EINVAL; irq = platform_get_irq(pdev, 0); if (irq < 0) return irq; size = sizeof(struct at_dma); size += plat_dat->nr_channels * sizeof(struct at_dma_chan); atdma = kzalloc(size, GFP_KERNEL); if (!atdma) return -ENOMEM; /* discover transaction capabilities */ atdma->dma_common.cap_mask = plat_dat->cap_mask; atdma->all_chan_mask = (1 << plat_dat->nr_channels) - 1; size = resource_size(io); if (!request_mem_region(io->start, size, pdev->dev.driver->name)) { err = -EBUSY; goto err_kfree; } atdma->regs = ioremap(io->start, size); if (!atdma->regs) { err = -ENOMEM; goto err_release_r; } atdma->clk = clk_get(&pdev->dev, "dma_clk"); if (IS_ERR(atdma->clk)) { err = PTR_ERR(atdma->clk); goto err_clk; } err = clk_prepare_enable(atdma->clk); if (err) goto err_clk_prepare; /* force dma off, just in case */ at_dma_off(atdma); err = request_irq(irq, at_dma_interrupt, 0, "at_hdmac", atdma); if (err) goto err_irq; platform_set_drvdata(pdev, atdma); /* create a pool of consistent memory blocks for hardware descriptors */ atdma->dma_desc_pool = dma_pool_create("at_hdmac_desc_pool", &pdev->dev, sizeof(struct at_desc), 4 /* word alignment */, 0); if (!atdma->dma_desc_pool) { dev_err(&pdev->dev, "No memory for descriptors dma pool\n"); err = -ENOMEM; goto err_desc_pool_create; } /* create a pool of consistent memory blocks for memset blocks */ atdma->memset_pool = dma_pool_create("at_hdmac_memset_pool", &pdev->dev, sizeof(int), 4, 0); if (!atdma->memset_pool) { dev_err(&pdev->dev, "No memory for memset dma pool\n"); err = -ENOMEM; goto err_memset_pool_create; } /* clear any pending interrupt */ while (dma_readl(atdma, EBCISR)) cpu_relax(); /* initialize channels related values */ INIT_LIST_HEAD(&atdma->dma_common.channels); for (i = 0; i < plat_dat->nr_channels; i++) { struct at_dma_chan *atchan = &atdma->chan[i]; atchan->mem_if = AT_DMA_MEM_IF; atchan->per_if = AT_DMA_PER_IF; atchan->chan_common.device = &atdma->dma_common; dma_cookie_init(&atchan->chan_common); list_add_tail(&atchan->chan_common.device_node, &atdma->dma_common.channels); atchan->ch_regs = atdma->regs + ch_regs(i); spin_lock_init(&atchan->lock); atchan->mask = 1 << i; INIT_LIST_HEAD(&atchan->active_list); INIT_LIST_HEAD(&atchan->queue); INIT_LIST_HEAD(&atchan->free_list); tasklet_init(&atchan->tasklet, atc_tasklet, (unsigned long)atchan); atc_enable_chan_irq(atdma, i); } /* set base routines */ atdma->dma_common.device_alloc_chan_resources = atc_alloc_chan_resources; atdma->dma_common.device_free_chan_resources = atc_free_chan_resources; atdma->dma_common.device_tx_status = atc_tx_status; atdma->dma_common.device_issue_pending = atc_issue_pending; atdma->dma_common.dev = &pdev->dev; /* set prep routines based on capability */ if (dma_has_cap(DMA_INTERLEAVE, atdma->dma_common.cap_mask)) atdma->dma_common.device_prep_interleaved_dma = atc_prep_dma_interleaved; if (dma_has_cap(DMA_MEMCPY, atdma->dma_common.cap_mask)) atdma->dma_common.device_prep_dma_memcpy = atc_prep_dma_memcpy; if (dma_has_cap(DMA_MEMSET, atdma->dma_common.cap_mask)) { atdma->dma_common.device_prep_dma_memset = atc_prep_dma_memset; atdma->dma_common.device_prep_dma_memset_sg = atc_prep_dma_memset_sg; atdma->dma_common.fill_align = DMAENGINE_ALIGN_4_BYTES; } if (dma_has_cap(DMA_SLAVE, atdma->dma_common.cap_mask)) { atdma->dma_common.device_prep_slave_sg = atc_prep_slave_sg; /* controller can do slave DMA: can trigger cyclic transfers */ dma_cap_set(DMA_CYCLIC, atdma->dma_common.cap_mask); atdma->dma_common.device_prep_dma_cyclic = atc_prep_dma_cyclic; atdma->dma_common.device_config = atc_config; atdma->dma_common.device_pause = atc_pause; atdma->dma_common.device_resume = atc_resume; atdma->dma_common.device_terminate_all = atc_terminate_all; atdma->dma_common.src_addr_widths = ATC_DMA_BUSWIDTHS; atdma->dma_common.dst_addr_widths = ATC_DMA_BUSWIDTHS; atdma->dma_common.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); atdma->dma_common.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST; } dma_writel(atdma, EN, AT_DMA_ENABLE); dev_info(&pdev->dev, "Atmel AHB DMA Controller ( %s%s%s), %d channels\n", dma_has_cap(DMA_MEMCPY, atdma->dma_common.cap_mask) ? "cpy " : "", dma_has_cap(DMA_MEMSET, atdma->dma_common.cap_mask) ? "set " : "", dma_has_cap(DMA_SLAVE, atdma->dma_common.cap_mask) ? "slave " : "", plat_dat->nr_channels); dma_async_device_register(&atdma->dma_common); /* * Do not return an error if the dmac node is not present in order to * not break the existing way of requesting channel with * dma_request_channel(). */ if (pdev->dev.of_node) { err = of_dma_controller_register(pdev->dev.of_node, at_dma_xlate, atdma); if (err) { dev_err(&pdev->dev, "could not register of_dma_controller\n"); goto err_of_dma_controller_register; } } return 0; err_of_dma_controller_register: dma_async_device_unregister(&atdma->dma_common); dma_pool_destroy(atdma->memset_pool); err_memset_pool_create: dma_pool_destroy(atdma->dma_desc_pool); err_desc_pool_create: free_irq(platform_get_irq(pdev, 0), atdma); err_irq: clk_disable_unprepare(atdma->clk); err_clk_prepare: clk_put(atdma->clk); err_clk: iounmap(atdma->regs); atdma->regs = NULL; err_release_r: release_mem_region(io->start, size); err_kfree: kfree(atdma); return err; } static int at_dma_remove(struct platform_device *pdev) { struct at_dma *atdma = platform_get_drvdata(pdev); struct dma_chan *chan, *_chan; struct resource *io; at_dma_off(atdma); if (pdev->dev.of_node) of_dma_controller_free(pdev->dev.of_node); dma_async_device_unregister(&atdma->dma_common); dma_pool_destroy(atdma->memset_pool); dma_pool_destroy(atdma->dma_desc_pool); free_irq(platform_get_irq(pdev, 0), atdma); list_for_each_entry_safe(chan, _chan, &atdma->dma_common.channels, device_node) { struct at_dma_chan *atchan = to_at_dma_chan(chan); /* Disable interrupts */ atc_disable_chan_irq(atdma, chan->chan_id); tasklet_kill(&atchan->tasklet); list_del(&chan->device_node); } clk_disable_unprepare(atdma->clk); clk_put(atdma->clk); iounmap(atdma->regs); atdma->regs = NULL; io = platform_get_resource(pdev, IORESOURCE_MEM, 0); release_mem_region(io->start, resource_size(io)); kfree(atdma); return 0; } static void at_dma_shutdown(struct platform_device *pdev) { struct at_dma *atdma = platform_get_drvdata(pdev); at_dma_off(platform_get_drvdata(pdev)); clk_disable_unprepare(atdma->clk); } static int at_dma_prepare(struct device *dev) { struct at_dma *atdma = dev_get_drvdata(dev); struct dma_chan *chan, *_chan; list_for_each_entry_safe(chan, _chan, &atdma->dma_common.channels, device_node) { struct at_dma_chan *atchan = to_at_dma_chan(chan); /* wait for transaction completion (except in cyclic case) */ if (atc_chan_is_enabled(atchan) && !atc_chan_is_cyclic(atchan)) return -EAGAIN; } return 0; } static void atc_suspend_cyclic(struct at_dma_chan *atchan) { struct dma_chan *chan = &atchan->chan_common; /* Channel should be paused by user * do it anyway even if it is not done already */ if (!atc_chan_is_paused(atchan)) { dev_warn(chan2dev(chan), "cyclic channel not paused, should be done by channel user\n"); atc_pause(chan); } /* now preserve additional data for cyclic operations */ /* next descriptor address in the cyclic list */ atchan->save_dscr = channel_readl(atchan, DSCR); vdbg_dump_regs(atchan); } static int at_dma_suspend_noirq(struct device *dev) { struct at_dma *atdma = dev_get_drvdata(dev); struct dma_chan *chan, *_chan; /* preserve data */ list_for_each_entry_safe(chan, _chan, &atdma->dma_common.channels, device_node) { struct at_dma_chan *atchan = to_at_dma_chan(chan); if (atc_chan_is_cyclic(atchan)) atc_suspend_cyclic(atchan); atchan->save_cfg = channel_readl(atchan, CFG); } atdma->save_imr = dma_readl(atdma, EBCIMR); /* disable DMA controller */ at_dma_off(atdma); clk_disable_unprepare(atdma->clk); return 0; } static void atc_resume_cyclic(struct at_dma_chan *atchan) { struct at_dma *atdma = to_at_dma(atchan->chan_common.device); /* restore channel status for cyclic descriptors list: * next descriptor in the cyclic list at the time of suspend */ channel_writel(atchan, SADDR, 0); channel_writel(atchan, DADDR, 0); channel_writel(atchan, CTRLA, 0); channel_writel(atchan, CTRLB, 0); channel_writel(atchan, DSCR, atchan->save_dscr); dma_writel(atdma, CHER, atchan->mask); /* channel pause status should be removed by channel user * We cannot take the initiative to do it here */ vdbg_dump_regs(atchan); } static int at_dma_resume_noirq(struct device *dev) { struct at_dma *atdma = dev_get_drvdata(dev); struct dma_chan *chan, *_chan; /* bring back DMA controller */ clk_prepare_enable(atdma->clk); dma_writel(atdma, EN, AT_DMA_ENABLE); /* clear any pending interrupt */ while (dma_readl(atdma, EBCISR)) cpu_relax(); /* restore saved data */ dma_writel(atdma, EBCIER, atdma->save_imr); list_for_each_entry_safe(chan, _chan, &atdma->dma_common.channels, device_node) { struct at_dma_chan *atchan = to_at_dma_chan(chan); channel_writel(atchan, CFG, atchan->save_cfg); if (atc_chan_is_cyclic(atchan)) atc_resume_cyclic(atchan); } return 0; } static const struct dev_pm_ops at_dma_dev_pm_ops = { .prepare = at_dma_prepare, .suspend_noirq = at_dma_suspend_noirq, .resume_noirq = at_dma_resume_noirq, }; static struct platform_driver at_dma_driver = { .remove = at_dma_remove, .shutdown = at_dma_shutdown, .id_table = atdma_devtypes, .driver = { .name = "at_hdmac", .pm = &at_dma_dev_pm_ops, .of_match_table = of_match_ptr(atmel_dma_dt_ids), }, }; static int __init at_dma_init(void) { return platform_driver_probe(&at_dma_driver, at_dma_probe); } subsys_initcall(at_dma_init); static void __exit at_dma_exit(void) { platform_driver_unregister(&at_dma_driver); } module_exit(at_dma_exit); MODULE_DESCRIPTION("Atmel AHB DMA Controller driver"); MODULE_AUTHOR("Nicolas Ferre <nicolas.ferre@atmel.com>"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:at_hdmac");
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