/* * Core driver for the Synopsys DesignWare DMA Controller * * Copyright (C) 2007-2008 Atmel Corporation * Copyright (C) 2010-2011 ST Microelectronics * * 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. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "dw_dmac_regs.h" #include "dmaengine.h" /* * This supports the Synopsys "DesignWare AHB Central DMA Controller", * (DW_ahb_dmac) which is used with various AMBA 2.0 systems (not all * of which use ARM any more). See the "Databook" from Synopsys for * information beyond what licensees probably provide. * * The driver has currently been tested only with the Atmel AT32AP7000, * which does not support descriptor writeback. */ static inline unsigned int dwc_get_dms(struct dw_dma_slave *slave) { return slave ? slave->dst_master : 0; } static inline unsigned int dwc_get_sms(struct dw_dma_slave *slave) { return slave ? slave->src_master : 1; } static inline void dwc_set_masters(struct dw_dma_chan *dwc) { struct dw_dma *dw = to_dw_dma(dwc->chan.device); struct dw_dma_slave *dws = dwc->chan.private; unsigned char mmax = dw->nr_masters - 1; if (dwc->request_line == ~0) { dwc->src_master = min_t(unsigned char, mmax, dwc_get_sms(dws)); dwc->dst_master = min_t(unsigned char, mmax, dwc_get_dms(dws)); } } #define DWC_DEFAULT_CTLLO(_chan) ({ \ struct dw_dma_chan *_dwc = to_dw_dma_chan(_chan); \ struct dma_slave_config *_sconfig = &_dwc->dma_sconfig; \ bool _is_slave = is_slave_direction(_dwc->direction); \ u8 _smsize = _is_slave ? _sconfig->src_maxburst : \ DW_DMA_MSIZE_16; \ u8 _dmsize = _is_slave ? _sconfig->dst_maxburst : \ DW_DMA_MSIZE_16; \ \ (DWC_CTLL_DST_MSIZE(_dmsize) \ | DWC_CTLL_SRC_MSIZE(_smsize) \ | DWC_CTLL_LLP_D_EN \ | DWC_CTLL_LLP_S_EN \ | DWC_CTLL_DMS(_dwc->dst_master) \ | DWC_CTLL_SMS(_dwc->src_master)); \ }) /* * Number of descriptors to allocate for each channel. This should be * made configurable somehow; preferably, the clients (at least the * ones using slave transfers) should be able to give us a hint. */ #define NR_DESCS_PER_CHANNEL 64 /*----------------------------------------------------------------------*/ static struct device *chan2dev(struct dma_chan *chan) { return &chan->dev->device; } static struct device *chan2parent(struct dma_chan *chan) { return chan->dev->device.parent; } static struct dw_desc *dwc_first_active(struct dw_dma_chan *dwc) { return to_dw_desc(dwc->active_list.next); } static struct dw_desc *dwc_desc_get(struct dw_dma_chan *dwc) { struct dw_desc *desc, *_desc; struct dw_desc *ret = NULL; unsigned int i = 0; unsigned long flags; spin_lock_irqsave(&dwc->lock, flags); list_for_each_entry_safe(desc, _desc, &dwc->free_list, desc_node) { i++; if (async_tx_test_ack(&desc->txd)) { list_del(&desc->desc_node); ret = desc; break; } dev_dbg(chan2dev(&dwc->chan), "desc %p not ACKed\n", desc); } spin_unlock_irqrestore(&dwc->lock, flags); dev_vdbg(chan2dev(&dwc->chan), "scanned %u descriptors on freelist\n", i); return ret; } /* * Move a descriptor, including any children, to the free list. * `desc' must not be on any lists. */ static void dwc_desc_put(struct dw_dma_chan *dwc, struct dw_desc *desc) { unsigned long flags; if (desc) { struct dw_desc *child; spin_lock_irqsave(&dwc->lock, flags); list_for_each_entry(child, &desc->tx_list, desc_node) dev_vdbg(chan2dev(&dwc->chan), "moving child desc %p to freelist\n", child); list_splice_init(&desc->tx_list, &dwc->free_list); dev_vdbg(chan2dev(&dwc->chan), "moving desc %p to freelist\n", desc); list_add(&desc->desc_node, &dwc->free_list); spin_unlock_irqrestore(&dwc->lock, flags); } } static void dwc_initialize(struct dw_dma_chan *dwc) { struct dw_dma *dw = to_dw_dma(dwc->chan.device); struct dw_dma_slave *dws = dwc->chan.private; u32 cfghi = DWC_CFGH_FIFO_MODE; u32 cfglo = DWC_CFGL_CH_PRIOR(dwc->priority); if (dwc->initialized == true) return; if (dws) { /* * We need controller-specific data to set up slave * transfers. */ BUG_ON(!dws->dma_dev || dws->dma_dev != dw->dma.dev); cfghi = dws->cfg_hi; cfglo |= dws->cfg_lo & ~DWC_CFGL_CH_PRIOR_MASK; } else { if (dwc->direction == DMA_MEM_TO_DEV) cfghi = DWC_CFGH_DST_PER(dwc->request_line); else if (dwc->direction == DMA_DEV_TO_MEM) cfghi = DWC_CFGH_SRC_PER(dwc->request_line); } channel_writel(dwc, CFG_LO, cfglo); channel_writel(dwc, CFG_HI, cfghi); /* Enable interrupts */ channel_set_bit(dw, MASK.XFER, dwc->mask); channel_set_bit(dw, MASK.ERROR, dwc->mask); dwc->initialized = true; } /*----------------------------------------------------------------------*/ static inline unsigned int dwc_fast_fls(unsigned long long v) { /* * We can be a lot more clever here, but this should take care * of the most common optimization. */ if (!(v & 7)) return 3; else if (!(v & 3)) return 2; else if (!(v & 1)) return 1; return 0; } static inline void dwc_dump_chan_regs(struct dw_dma_chan *dwc) { dev_err(chan2dev(&dwc->chan), " SAR: 0x%x DAR: 0x%x LLP: 0x%x CTL: 0x%x:%08x\n", channel_readl(dwc, SAR), channel_readl(dwc, DAR), channel_readl(dwc, LLP), channel_readl(dwc, CTL_HI), channel_readl(dwc, CTL_LO)); } static inline void dwc_chan_disable(struct dw_dma *dw, struct dw_dma_chan *dwc) { channel_clear_bit(dw, CH_EN, dwc->mask); while (dma_readl(dw, CH_EN) & dwc->mask) cpu_relax(); } /*----------------------------------------------------------------------*/ /* Perform single block transfer */ static inline void dwc_do_single_block(struct dw_dma_chan *dwc, struct dw_desc *desc) { struct dw_dma *dw = to_dw_dma(dwc->chan.device); u32 ctllo; /* Software emulation of LLP mode relies on interrupts to continue * multi block transfer. */ ctllo = desc->lli.ctllo | DWC_CTLL_INT_EN; channel_writel(dwc, SAR, desc->lli.sar); channel_writel(dwc, DAR, desc->lli.dar); channel_writel(dwc, CTL_LO, ctllo); channel_writel(dwc, CTL_HI, desc->lli.ctlhi); channel_set_bit(dw, CH_EN, dwc->mask); /* Move pointer to next descriptor */ dwc->tx_node_active = dwc->tx_node_active->next; } /* Called with dwc->lock held and bh disabled */ static void dwc_dostart(struct dw_dma_chan *dwc, struct dw_desc *first) { struct dw_dma *dw = to_dw_dma(dwc->chan.device); unsigned long was_soft_llp; /* ASSERT: channel is idle */ if (dma_readl(dw, CH_EN) & dwc->mask) { dev_err(chan2dev(&dwc->chan), "BUG: Attempted to start non-idle channel\n"); dwc_dump_chan_regs(dwc); /* The tasklet will hopefully advance the queue... */ return; } if (dwc->nollp) { was_soft_llp = test_and_set_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags); if (was_soft_llp) { dev_err(chan2dev(&dwc->chan), "BUG: Attempted to start new LLP transfer " "inside ongoing one\n"); return; } dwc_initialize(dwc); dwc->residue = first->total_len; dwc->tx_node_active = &first->tx_list; /* Submit first block */ dwc_do_single_block(dwc, first); return; } dwc_initialize(dwc); channel_writel(dwc, LLP, first->txd.phys); channel_writel(dwc, CTL_LO, DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN); channel_writel(dwc, CTL_HI, 0); channel_set_bit(dw, CH_EN, dwc->mask); } /*----------------------------------------------------------------------*/ static void dwc_descriptor_complete(struct dw_dma_chan *dwc, struct dw_desc *desc, bool callback_required) { dma_async_tx_callback callback = NULL; void *param = NULL; struct dma_async_tx_descriptor *txd = &desc->txd; struct dw_desc *child; unsigned long flags; dev_vdbg(chan2dev(&dwc->chan), "descriptor %u complete\n", txd->cookie); spin_lock_irqsave(&dwc->lock, flags); dma_cookie_complete(txd); if (callback_required) { callback = txd->callback; param = txd->callback_param; } /* async_tx_ack */ list_for_each_entry(child, &desc->tx_list, desc_node) async_tx_ack(&child->txd); async_tx_ack(&desc->txd); list_splice_init(&desc->tx_list, &dwc->free_list); list_move(&desc->desc_node, &dwc->free_list); if (!is_slave_direction(dwc->direction)) { struct device *parent = chan2parent(&dwc->chan); if (!(txd->flags & DMA_COMPL_SKIP_DEST_UNMAP)) { if (txd->flags & DMA_COMPL_DEST_UNMAP_SINGLE) dma_unmap_single(parent, desc->lli.dar, desc->total_len, DMA_FROM_DEVICE); else dma_unmap_page(parent, desc->lli.dar, desc->total_len, DMA_FROM_DEVICE); } if (!(txd->flags & DMA_COMPL_SKIP_SRC_UNMAP)) { if (txd->flags & DMA_COMPL_SRC_UNMAP_SINGLE) dma_unmap_single(parent, desc->lli.sar, desc->total_len, DMA_TO_DEVICE); else dma_unmap_page(parent, desc->lli.sar, desc->total_len, DMA_TO_DEVICE); } } spin_unlock_irqrestore(&dwc->lock, flags); if (callback) callback(param); } static void dwc_complete_all(struct dw_dma *dw, struct dw_dma_chan *dwc) { struct dw_desc *desc, *_desc; LIST_HEAD(list); unsigned long flags; spin_lock_irqsave(&dwc->lock, flags); if (dma_readl(dw, CH_EN) & dwc->mask) { dev_err(chan2dev(&dwc->chan), "BUG: XFER bit set, but channel not idle!\n"); /* Try to continue after resetting the channel... */ dwc_chan_disable(dw, dwc); } /* * Submit queued descriptors ASAP, i.e. before we go through * the completed ones. */ list_splice_init(&dwc->active_list, &list); if (!list_empty(&dwc->queue)) { list_move(dwc->queue.next, &dwc->active_list); dwc_dostart(dwc, dwc_first_active(dwc)); } spin_unlock_irqrestore(&dwc->lock, flags); list_for_each_entry_safe(desc, _desc, &list, desc_node) dwc_descriptor_complete(dwc, desc, true); } /* Returns how many bytes were already received from source */ static inline u32 dwc_get_sent(struct dw_dma_chan *dwc) { u32 ctlhi = channel_readl(dwc, CTL_HI); u32 ctllo = channel_readl(dwc, CTL_LO); return (ctlhi & DWC_CTLH_BLOCK_TS_MASK) * (1 << (ctllo >> 4 & 7)); } static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc) { dma_addr_t llp; struct dw_desc *desc, *_desc; struct dw_desc *child; u32 status_xfer; unsigned long flags; spin_lock_irqsave(&dwc->lock, flags); llp = channel_readl(dwc, LLP); status_xfer = dma_readl(dw, RAW.XFER); if (status_xfer & dwc->mask) { /* Everything we've submitted is done */ dma_writel(dw, CLEAR.XFER, dwc->mask); if (test_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags)) { struct list_head *head, *active = dwc->tx_node_active; /* * We are inside first active descriptor. * Otherwise something is really wrong. */ desc = dwc_first_active(dwc); head = &desc->tx_list; if (active != head) { /* Update desc to reflect last sent one */ if (active != head->next) desc = to_dw_desc(active->prev); dwc->residue -= desc->len; child = to_dw_desc(active); /* Submit next block */ dwc_do_single_block(dwc, child); spin_unlock_irqrestore(&dwc->lock, flags); return; } /* We are done here */ clear_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags); } dwc->residue = 0; spin_unlock_irqrestore(&dwc->lock, flags); dwc_complete_all(dw, dwc); return; } if (list_empty(&dwc->active_list)) { dwc->residue = 0; spin_unlock_irqrestore(&dwc->lock, flags); return; } if (test_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags)) { dev_vdbg(chan2dev(&dwc->chan), "%s: soft LLP mode\n", __func__); spin_unlock_irqrestore(&dwc->lock, flags); return; } dev_vdbg(chan2dev(&dwc->chan), "%s: llp=0x%llx\n", __func__, (unsigned long long)llp); list_for_each_entry_safe(desc, _desc, &dwc->active_list, desc_node) { /* Initial residue value */ dwc->residue = desc->total_len; /* Check first descriptors addr */ if (desc->txd.phys == llp) { spin_unlock_irqrestore(&dwc->lock, flags); return; } /* Check first descriptors llp */ if (desc->lli.llp == llp) { /* This one is currently in progress */ dwc->residue -= dwc_get_sent(dwc); spin_unlock_irqrestore(&dwc->lock, flags); return; } dwc->residue -= desc->len; list_for_each_entry(child, &desc->tx_list, desc_node) { if (child->lli.llp == llp) { /* Currently in progress */ dwc->residue -= dwc_get_sent(dwc); spin_unlock_irqrestore(&dwc->lock, flags); return; } dwc->residue -= child->len; } /* * No descriptors so far seem to be in progress, i.e. * this one must be done. */ spin_unlock_irqrestore(&dwc->lock, flags); dwc_descriptor_complete(dwc, desc, true); spin_lock_irqsave(&dwc->lock, flags); } dev_err(chan2dev(&dwc->chan), "BUG: All descriptors done, but channel not idle!\n"); /* Try to continue after resetting the channel... */ dwc_chan_disable(dw, dwc); if (!list_empty(&dwc->queue)) { list_move(dwc->queue.next, &dwc->active_list); dwc_dostart(dwc, dwc_first_active(dwc)); } spin_unlock_irqrestore(&dwc->lock, flags); } static inline void dwc_dump_lli(struct dw_dma_chan *dwc, struct dw_lli *lli) { dev_crit(chan2dev(&dwc->chan), " desc: s0x%x d0x%x l0x%x c0x%x:%x\n", lli->sar, lli->dar, lli->llp, lli->ctlhi, lli->ctllo); } static void dwc_handle_error(struct dw_dma *dw, struct dw_dma_chan *dwc) { struct dw_desc *bad_desc; struct dw_desc *child; unsigned long flags; dwc_scan_descriptors(dw, dwc); spin_lock_irqsave(&dwc->lock, flags); /* * The descriptor currently at the head of the active list is * borked. Since we don't have any way to report errors, we'll * just have to scream loudly and try to carry on. */ bad_desc = dwc_first_active(dwc); list_del_init(&bad_desc->desc_node); list_move(dwc->queue.next, dwc->active_list.prev); /* Clear the error flag and try to restart the controller */ dma_writel(dw, CLEAR.ERROR, dwc->mask); if (!list_empty(&dwc->active_list)) dwc_dostart(dwc, dwc_first_active(dwc)); /* * WARN 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_WARN(chan2dev(&dwc->chan), "Bad descriptor submitted for DMA!\n" " cookie: %d\n", bad_desc->txd.cookie); dwc_dump_lli(dwc, &bad_desc->lli); list_for_each_entry(child, &bad_desc->tx_list, desc_node) dwc_dump_lli(dwc, &child->lli); spin_unlock_irqrestore(&dwc->lock, flags); /* Pretend the descriptor completed successfully */ dwc_descriptor_complete(dwc, bad_desc, true); } /* --------------------- Cyclic DMA API extensions -------------------- */ inline dma_addr_t dw_dma_get_src_addr(struct dma_chan *chan) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); return channel_readl(dwc, SAR); } EXPORT_SYMBOL(dw_dma_get_src_addr); inline dma_addr_t dw_dma_get_dst_addr(struct dma_chan *chan) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); return channel_readl(dwc, DAR); } EXPORT_SYMBOL(dw_dma_get_dst_addr); /* Called with dwc->lock held and all DMAC interrupts disabled */ static void dwc_handle_cyclic(struct dw_dma *dw, struct dw_dma_chan *dwc, u32 status_err, u32 status_xfer) { unsigned long flags; if (dwc->mask) { void (*callback)(void *param); void *callback_param; dev_vdbg(chan2dev(&dwc->chan), "new cyclic period llp 0x%08x\n", channel_readl(dwc, LLP)); callback = dwc->cdesc->period_callback; callback_param = dwc->cdesc->period_callback_param; if (callback) callback(callback_param); } /* * Error and transfer complete are highly unlikely, and will most * likely be due to a configuration error by the user. */ if (unlikely(status_err & dwc->mask) || unlikely(status_xfer & dwc->mask)) { int i; dev_err(chan2dev(&dwc->chan), "cyclic DMA unexpected %s " "interrupt, stopping DMA transfer\n", status_xfer ? "xfer" : "error"); spin_lock_irqsave(&dwc->lock, flags); dwc_dump_chan_regs(dwc); dwc_chan_disable(dw, dwc); /* Make sure DMA does not restart by loading a new list */ channel_writel(dwc, LLP, 0); channel_writel(dwc, CTL_LO, 0); channel_writel(dwc, CTL_HI, 0); dma_writel(dw, CLEAR.ERROR, dwc->mask); dma_writel(dw, CLEAR.XFER, dwc->mask); for (i = 0; i < dwc->cdesc->periods; i++) dwc_dump_lli(dwc, &dwc->cdesc->desc[i]->lli); spin_unlock_irqrestore(&dwc->lock, flags); } } /* ------------------------------------------------------------------------- */ static void dw_dma_tasklet(unsigned long data) { struct dw_dma *dw = (struct dw_dma *)data; struct dw_dma_chan *dwc; u32 status_xfer; u32 status_err; int i; status_xfer = dma_readl(dw, RAW.XFER); status_err = dma_readl(dw, RAW.ERROR); dev_vdbg(dw->dma.dev, "%s: status_err=%x\n", __func__, status_err); for (i = 0; i < dw->dma.chancnt; i++) { dwc = &dw->chan[i]; if (test_bit(DW_DMA_IS_CYCLIC, &dwc->flags)) dwc_handle_cyclic(dw, dwc, status_err, status_xfer); else if (status_err & (1 << i)) dwc_handle_error(dw, dwc); else if (status_xfer & (1 << i)) dwc_scan_descriptors(dw, dwc); } /* * Re-enable interrupts. */ channel_set_bit(dw, MASK.XFER, dw->all_chan_mask); channel_set_bit(dw, MASK.ERROR, dw->all_chan_mask); } static irqreturn_t dw_dma_interrupt(int irq, void *dev_id) { struct dw_dma *dw = dev_id; u32 status; dev_vdbg(dw->dma.dev, "%s: status=0x%x\n", __func__, dma_readl(dw, STATUS_INT)); /* * Just disable the interrupts. We'll turn them back on in the * softirq handler. */ channel_clear_bit(dw, MASK.XFER, dw->all_chan_mask); channel_clear_bit(dw, MASK.ERROR, dw->all_chan_mask); status = dma_readl(dw, STATUS_INT); if (status) { dev_err(dw->dma.dev, "BUG: Unexpected interrupts pending: 0x%x\n", status); /* Try to recover */ channel_clear_bit(dw, MASK.XFER, (1 << 8) - 1); channel_clear_bit(dw, MASK.SRC_TRAN, (1 << 8) - 1); channel_clear_bit(dw, MASK.DST_TRAN, (1 << 8) - 1); channel_clear_bit(dw, MASK.ERROR, (1 << 8) - 1); } tasklet_schedule(&dw->tasklet); return IRQ_HANDLED; } /*----------------------------------------------------------------------*/ static dma_cookie_t dwc_tx_submit(struct dma_async_tx_descriptor *tx) { struct dw_desc *desc = txd_to_dw_desc(tx); struct dw_dma_chan *dwc = to_dw_dma_chan(tx->chan); dma_cookie_t cookie; unsigned long flags; spin_lock_irqsave(&dwc->lock, flags); cookie = dma_cookie_assign(tx); /* * REVISIT: We should attempt to chain as many descriptors as * possible, perhaps even appending to those already submitted * for DMA. But this is hard to do in a race-free manner. */ if (list_empty(&dwc->active_list)) { dev_vdbg(chan2dev(tx->chan), "%s: started %u\n", __func__, desc->txd.cookie); list_add_tail(&desc->desc_node, &dwc->active_list); dwc_dostart(dwc, dwc_first_active(dwc)); } else { dev_vdbg(chan2dev(tx->chan), "%s: queued %u\n", __func__, desc->txd.cookie); list_add_tail(&desc->desc_node, &dwc->queue); } spin_unlock_irqrestore(&dwc->lock, flags); return cookie; } static struct dma_async_tx_descriptor * dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, size_t len, unsigned long flags) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); struct dw_dma *dw = to_dw_dma(chan->device); struct dw_desc *desc; struct dw_desc *first; struct dw_desc *prev; size_t xfer_count; size_t offset; unsigned int src_width; unsigned int dst_width; unsigned int data_width; u32 ctllo; dev_vdbg(chan2dev(chan), "%s: d0x%llx s0x%llx l0x%zx f0x%lx\n", __func__, (unsigned long long)dest, (unsigned long long)src, len, flags); if (unlikely(!len)) { dev_dbg(chan2dev(chan), "%s: length is zero!\n", __func__); return NULL; } dwc->direction = DMA_MEM_TO_MEM; data_width = min_t(unsigned int, dw->data_width[dwc->src_master], dw->data_width[dwc->dst_master]); src_width = dst_width = min_t(unsigned int, data_width, dwc_fast_fls(src | dest | len)); ctllo = DWC_DEFAULT_CTLLO(chan) | DWC_CTLL_DST_WIDTH(dst_width) | DWC_CTLL_SRC_WIDTH(src_width) | DWC_CTLL_DST_INC | DWC_CTLL_SRC_INC | DWC_CTLL_FC_M2M; prev = first = NULL; for (offset = 0; offset < len; offset += xfer_count << src_width) { xfer_count = min_t(size_t, (len - offset) >> src_width, dwc->block_size); desc = dwc_desc_get(dwc); if (!desc) goto err_desc_get; desc->lli.sar = src + offset; desc->lli.dar = dest + offset; desc->lli.ctllo = ctllo; desc->lli.ctlhi = xfer_count; desc->len = xfer_count << src_width; if (!first) { first = desc; } else { prev->lli.llp = desc->txd.phys; list_add_tail(&desc->desc_node, &first->tx_list); } prev = desc; } if (flags & DMA_PREP_INTERRUPT) /* Trigger interrupt after last block */ prev->lli.ctllo |= DWC_CTLL_INT_EN; prev->lli.llp = 0; first->txd.flags = flags; first->total_len = len; return &first->txd; err_desc_get: dwc_desc_put(dwc, first); return NULL; } static struct dma_async_tx_descriptor * dwc_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 dw_dma_chan *dwc = to_dw_dma_chan(chan); struct dw_dma *dw = to_dw_dma(chan->device); struct dma_slave_config *sconfig = &dwc->dma_sconfig; struct dw_desc *prev; struct dw_desc *first; u32 ctllo; dma_addr_t reg; unsigned int reg_width; unsigned int mem_width; unsigned int data_width; unsigned int i; struct scatterlist *sg; size_t total_len = 0; dev_vdbg(chan2dev(chan), "%s\n", __func__); if (unlikely(!is_slave_direction(direction) || !sg_len)) return NULL; dwc->direction = direction; prev = first = NULL; switch (direction) { case DMA_MEM_TO_DEV: reg_width = __fls(sconfig->dst_addr_width); reg = sconfig->dst_addr; ctllo = (DWC_DEFAULT_CTLLO(chan) | DWC_CTLL_DST_WIDTH(reg_width) | DWC_CTLL_DST_FIX | DWC_CTLL_SRC_INC); ctllo |= sconfig->device_fc ? DWC_CTLL_FC(DW_DMA_FC_P_M2P) : DWC_CTLL_FC(DW_DMA_FC_D_M2P); data_width = dw->data_width[dwc->src_master]; for_each_sg(sgl, sg, sg_len, i) { struct dw_desc *desc; u32 len, dlen, mem; mem = sg_dma_address(sg); len = sg_dma_len(sg); mem_width = min_t(unsigned int, data_width, dwc_fast_fls(mem | len)); slave_sg_todev_fill_desc: desc = dwc_desc_get(dwc); if (!desc) { dev_err(chan2dev(chan), "not enough descriptors available\n"); goto err_desc_get; } desc->lli.sar = mem; desc->lli.dar = reg; desc->lli.ctllo = ctllo | DWC_CTLL_SRC_WIDTH(mem_width); if ((len >> mem_width) > dwc->block_size) { dlen = dwc->block_size << mem_width; mem += dlen; len -= dlen; } else { dlen = len; len = 0; } desc->lli.ctlhi = dlen >> mem_width; desc->len = dlen; if (!first) { first = desc; } else { prev->lli.llp = desc->txd.phys; list_add_tail(&desc->desc_node, &first->tx_list); } prev = desc; total_len += dlen; if (len) goto slave_sg_todev_fill_desc; } break; case DMA_DEV_TO_MEM: reg_width = __fls(sconfig->src_addr_width); reg = sconfig->src_addr; ctllo = (DWC_DEFAULT_CTLLO(chan) | DWC_CTLL_SRC_WIDTH(reg_width) | DWC_CTLL_DST_INC | DWC_CTLL_SRC_FIX); ctllo |= sconfig->device_fc ? DWC_CTLL_FC(DW_DMA_FC_P_P2M) : DWC_CTLL_FC(DW_DMA_FC_D_P2M); data_width = dw->data_width[dwc->dst_master]; for_each_sg(sgl, sg, sg_len, i) { struct dw_desc *desc; u32 len, dlen, mem; mem = sg_dma_address(sg); len = sg_dma_len(sg); mem_width = min_t(unsigned int, data_width, dwc_fast_fls(mem | len)); slave_sg_fromdev_fill_desc: desc = dwc_desc_get(dwc); if (!desc) { dev_err(chan2dev(chan), "not enough descriptors available\n"); goto err_desc_get; } desc->lli.sar = reg; desc->lli.dar = mem; desc->lli.ctllo = ctllo | DWC_CTLL_DST_WIDTH(mem_width); if ((len >> reg_width) > dwc->block_size) { dlen = dwc->block_size << reg_width; mem += dlen; len -= dlen; } else { dlen = len; len = 0; } desc->lli.ctlhi = dlen >> reg_width; desc->len = dlen; if (!first) { first = desc; } else { prev->lli.llp = desc->txd.phys; list_add_tail(&desc->desc_node, &first->tx_list); } prev = desc; total_len += dlen; if (len) goto slave_sg_fromdev_fill_desc; } break; default: return NULL; } if (flags & DMA_PREP_INTERRUPT) /* Trigger interrupt after last block */ prev->lli.ctllo |= DWC_CTLL_INT_EN; prev->lli.llp = 0; first->total_len = total_len; return &first->txd; err_desc_get: dwc_desc_put(dwc, first); return NULL; } /* * Fix sconfig's burst size according to dw_dmac. We need to convert them as: * 1 -> 0, 4 -> 1, 8 -> 2, 16 -> 3. * * NOTE: burst size 2 is not supported by controller. * * This can be done by finding least significant bit set: n & (n - 1) */ static inline void convert_burst(u32 *maxburst) { if (*maxburst > 1) *maxburst = fls(*maxburst) - 2; else *maxburst = 0; } static int set_runtime_config(struct dma_chan *chan, struct dma_slave_config *sconfig) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); /* Check if chan will be configured for slave transfers */ if (!is_slave_direction(sconfig->direction)) return -EINVAL; memcpy(&dwc->dma_sconfig, sconfig, sizeof(*sconfig)); dwc->direction = sconfig->direction; /* Take the request line from slave_id member */ if (dwc->request_line == ~0) dwc->request_line = sconfig->slave_id; convert_burst(&dwc->dma_sconfig.src_maxburst); convert_burst(&dwc->dma_sconfig.dst_maxburst); return 0; } static inline void dwc_chan_pause(struct dw_dma_chan *dwc) { u32 cfglo = channel_readl(dwc, CFG_LO); unsigned int count = 20; /* timeout iterations */ channel_writel(dwc, CFG_LO, cfglo | DWC_CFGL_CH_SUSP); while (!(channel_readl(dwc, CFG_LO) & DWC_CFGL_FIFO_EMPTY) && count--) udelay(2); dwc->paused = true; } static inline void dwc_chan_resume(struct dw_dma_chan *dwc) { u32 cfglo = channel_readl(dwc, CFG_LO); channel_writel(dwc, CFG_LO, cfglo & ~DWC_CFGL_CH_SUSP); dwc->paused = false; } static int dwc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, unsigned long arg) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); struct dw_dma *dw = to_dw_dma(chan->device); struct dw_desc *desc, *_desc; unsigned long flags; LIST_HEAD(list); if (cmd == DMA_PAUSE) { spin_lock_irqsave(&dwc->lock, flags); dwc_chan_pause(dwc); spin_unlock_irqrestore(&dwc->lock, flags); } else if (cmd == DMA_RESUME) { if (!dwc->paused) return 0; spin_lock_irqsave(&dwc->lock, flags); dwc_chan_resume(dwc); spin_unlock_irqrestore(&dwc->lock, flags); } else if (cmd == DMA_TERMINATE_ALL) { spin_lock_irqsave(&dwc->lock, flags); clear_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags); dwc_chan_disable(dw, dwc); dwc_chan_resume(dwc); /* active_list entries will end up before queued entries */ list_splice_init(&dwc->queue, &list); list_splice_init(&dwc->active_list, &list); spin_unlock_irqrestore(&dwc->lock, flags); /* Flush all pending and queued descriptors */ list_for_each_entry_safe(desc, _desc, &list, desc_node) dwc_descriptor_complete(dwc, desc, false); } else if (cmd == DMA_SLAVE_CONFIG) { return set_runtime_config(chan, (struct dma_slave_config *)arg); } else { return -ENXIO; } return 0; } static inline u32 dwc_get_residue(struct dw_dma_chan *dwc) { unsigned long flags; u32 residue; spin_lock_irqsave(&dwc->lock, flags); residue = dwc->residue; if (test_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags) && residue) residue -= dwc_get_sent(dwc); spin_unlock_irqrestore(&dwc->lock, flags); return residue; } static enum dma_status dwc_tx_status(struct dma_chan *chan, dma_cookie_t cookie, struct dma_tx_state *txstate) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); enum dma_status ret; ret = dma_cookie_status(chan, cookie, txstate); if (ret != DMA_SUCCESS) { dwc_scan_descriptors(to_dw_dma(chan->device), dwc); ret = dma_cookie_status(chan, cookie, txstate); } if (ret != DMA_SUCCESS) dma_set_residue(txstate, dwc_get_residue(dwc)); if (dwc->paused) return DMA_PAUSED; return ret; } static void dwc_issue_pending(struct dma_chan *chan) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); if (!list_empty(&dwc->queue)) dwc_scan_descriptors(to_dw_dma(chan->device), dwc); } static int dwc_alloc_chan_resources(struct dma_chan *chan) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); struct dw_dma *dw = to_dw_dma(chan->device); struct dw_desc *desc; int i; unsigned long flags; dev_vdbg(chan2dev(chan), "%s\n", __func__); /* ASSERT: channel is idle */ if (dma_readl(dw, CH_EN) & dwc->mask) { dev_dbg(chan2dev(chan), "DMA channel not idle?\n"); return -EIO; } dma_cookie_init(chan); /* * NOTE: some controllers may have additional features that we * need to initialize here, like "scatter-gather" (which * doesn't mean what you think it means), and status writeback. */ dwc_set_masters(dwc); spin_lock_irqsave(&dwc->lock, flags); i = dwc->descs_allocated; while (dwc->descs_allocated < NR_DESCS_PER_CHANNEL) { dma_addr_t phys; spin_unlock_irqrestore(&dwc->lock, flags); desc = dma_pool_alloc(dw->desc_pool, GFP_ATOMIC, &phys); if (!desc) goto err_desc_alloc; memset(desc, 0, sizeof(struct dw_desc)); INIT_LIST_HEAD(&desc->tx_list); dma_async_tx_descriptor_init(&desc->txd, chan); desc->txd.tx_submit = dwc_tx_submit; desc->txd.flags = DMA_CTRL_ACK; desc->txd.phys = phys; dwc_desc_put(dwc, desc); spin_lock_irqsave(&dwc->lock, flags); i = ++dwc->descs_allocated; } spin_unlock_irqrestore(&dwc->lock, flags); dev_dbg(chan2dev(chan), "%s: allocated %d descriptors\n", __func__, i); return i; err_desc_alloc: dev_info(chan2dev(chan), "only allocated %d descriptors\n", i); return i; } static void dwc_free_chan_resources(struct dma_chan *chan) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); struct dw_dma *dw = to_dw_dma(chan->device); struct dw_desc *desc, *_desc; unsigned long flags; LIST_HEAD(list); dev_dbg(chan2dev(chan), "%s: descs allocated=%u\n", __func__, dwc->descs_allocated); /* ASSERT: channel is idle */ BUG_ON(!list_empty(&dwc->active_list)); BUG_ON(!list_empty(&dwc->queue)); BUG_ON(dma_readl(to_dw_dma(chan->device), CH_EN) & dwc->mask); spin_lock_irqsave(&dwc->lock, flags); list_splice_init(&dwc->free_list, &list); dwc->descs_allocated = 0; dwc->initialized = false; dwc->request_line = ~0; /* Disable interrupts */ channel_clear_bit(dw, MASK.XFER, dwc->mask); channel_clear_bit(dw, MASK.ERROR, dwc->mask); spin_unlock_irqrestore(&dwc->lock, flags); list_for_each_entry_safe(desc, _desc, &list, desc_node) { dev_vdbg(chan2dev(chan), " freeing descriptor %p\n", desc); dma_pool_free(dw->desc_pool, desc, desc->txd.phys); } dev_vdbg(chan2dev(chan), "%s: done\n", __func__); } /*----------------------------------------------------------------------*/ struct dw_dma_of_filter_args { struct dw_dma *dw; unsigned int req; unsigned int src; unsigned int dst; }; static bool dw_dma_of_filter(struct dma_chan *chan, void *param) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); struct dw_dma_of_filter_args *fargs = param; /* Ensure the device matches our channel */ if (chan->device != &fargs->dw->dma) return false; dwc->request_line = fargs->req; dwc->src_master = fargs->src; dwc->dst_master = fargs->dst; return true; } static struct dma_chan *dw_dma_of_xlate(struct of_phandle_args *dma_spec, struct of_dma *ofdma) { struct dw_dma *dw = ofdma->of_dma_data; struct dw_dma_of_filter_args fargs = { .dw = dw, }; dma_cap_mask_t cap; if (dma_spec->args_count != 3) return NULL; fargs.req = dma_spec->args[0]; fargs.src = dma_spec->args[1]; fargs.dst = dma_spec->args[2]; if (WARN_ON(fargs.req >= DW_DMA_MAX_NR_REQUESTS || fargs.src >= dw->nr_masters || fargs.dst >= dw->nr_masters)) return NULL; dma_cap_zero(cap); dma_cap_set(DMA_SLAVE, cap); /* TODO: there should be a simpler way to do this */ return dma_request_channel(cap, dw_dma_of_filter, &fargs); } #ifdef CONFIG_ACPI static bool dw_dma_acpi_filter(struct dma_chan *chan, void *param) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); struct acpi_dma_spec *dma_spec = param; if (chan->device->dev != dma_spec->dev || chan->chan_id != dma_spec->chan_id) return false; dwc->request_line = dma_spec->slave_id; dwc->src_master = dwc_get_sms(NULL); dwc->dst_master = dwc_get_dms(NULL); return true; } static void dw_dma_acpi_controller_register(struct dw_dma *dw) { struct device *dev = dw->dma.dev; struct acpi_dma_filter_info *info; int ret; info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL); if (!info) return; dma_cap_zero(info->dma_cap); dma_cap_set(DMA_SLAVE, info->dma_cap); info->filter_fn = dw_dma_acpi_filter; ret = devm_acpi_dma_controller_register(dev, acpi_dma_simple_xlate, info); if (ret) dev_err(dev, "could not register acpi_dma_controller\n"); } #else /* !CONFIG_ACPI */ static inline void dw_dma_acpi_controller_register(struct dw_dma *dw) {} #endif /* !CONFIG_ACPI */ /* --------------------- Cyclic DMA API extensions -------------------- */ /** * dw_dma_cyclic_start - start the cyclic DMA transfer * @chan: the DMA channel to start * * Must be called with soft interrupts disabled. Returns zero on success or * -errno on failure. */ int dw_dma_cyclic_start(struct dma_chan *chan) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); struct dw_dma *dw = to_dw_dma(dwc->chan.device); unsigned long flags; if (!test_bit(DW_DMA_IS_CYCLIC, &dwc->flags)) { dev_err(chan2dev(&dwc->chan), "missing prep for cyclic DMA\n"); return -ENODEV; } spin_lock_irqsave(&dwc->lock, flags); /* Assert channel is idle */ if (dma_readl(dw, CH_EN) & dwc->mask) { dev_err(chan2dev(&dwc->chan), "BUG: Attempted to start non-idle channel\n"); dwc_dump_chan_regs(dwc); spin_unlock_irqrestore(&dwc->lock, flags); return -EBUSY; } dma_writel(dw, CLEAR.ERROR, dwc->mask); dma_writel(dw, CLEAR.XFER, dwc->mask); /* Setup DMAC channel registers */ channel_writel(dwc, LLP, dwc->cdesc->desc[0]->txd.phys); channel_writel(dwc, CTL_LO, DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN); channel_writel(dwc, CTL_HI, 0); channel_set_bit(dw, CH_EN, dwc->mask); spin_unlock_irqrestore(&dwc->lock, flags); return 0; } EXPORT_SYMBOL(dw_dma_cyclic_start); /** * dw_dma_cyclic_stop - stop the cyclic DMA transfer * @chan: the DMA channel to stop * * Must be called with soft interrupts disabled. */ void dw_dma_cyclic_stop(struct dma_chan *chan) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); struct dw_dma *dw = to_dw_dma(dwc->chan.device); unsigned long flags; spin_lock_irqsave(&dwc->lock, flags); dwc_chan_disable(dw, dwc); spin_unlock_irqrestore(&dwc->lock, flags); } EXPORT_SYMBOL(dw_dma_cyclic_stop); /** * dw_dma_cyclic_prep - 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 * * Must be called before trying to start the transfer. Returns a valid struct * dw_cyclic_desc if successful or an ERR_PTR(-errno) if not successful. */ struct dw_cyclic_desc *dw_dma_cyclic_prep(struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len, size_t period_len, enum dma_transfer_direction direction) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); struct dma_slave_config *sconfig = &dwc->dma_sconfig; struct dw_cyclic_desc *cdesc; struct dw_cyclic_desc *retval = NULL; struct dw_desc *desc; struct dw_desc *last = NULL; unsigned long was_cyclic; unsigned int reg_width; unsigned int periods; unsigned int i; unsigned long flags; spin_lock_irqsave(&dwc->lock, flags); if (dwc->nollp) { spin_unlock_irqrestore(&dwc->lock, flags); dev_dbg(chan2dev(&dwc->chan), "channel doesn't support LLP transfers\n"); return ERR_PTR(-EINVAL); } if (!list_empty(&dwc->queue) || !list_empty(&dwc->active_list)) { spin_unlock_irqrestore(&dwc->lock, flags); dev_dbg(chan2dev(&dwc->chan), "queue and/or active list are not empty\n"); return ERR_PTR(-EBUSY); } was_cyclic = test_and_set_bit(DW_DMA_IS_CYCLIC, &dwc->flags); spin_unlock_irqrestore(&dwc->lock, flags); if (was_cyclic) { dev_dbg(chan2dev(&dwc->chan), "channel already prepared for cyclic DMA\n"); return ERR_PTR(-EBUSY); } retval = ERR_PTR(-EINVAL); if (unlikely(!is_slave_direction(direction))) goto out_err; dwc->direction = direction; if (direction == DMA_MEM_TO_DEV) reg_width = __ffs(sconfig->dst_addr_width); else reg_width = __ffs(sconfig->src_addr_width); periods = buf_len / period_len; /* Check for too big/unaligned periods and unaligned DMA buffer. */ if (period_len > (dwc->block_size << reg_width)) goto out_err; if (unlikely(period_len & ((1 << reg_width) - 1))) goto out_err; if (unlikely(buf_addr & ((1 << reg_width) - 1))) goto out_err; retval = ERR_PTR(-ENOMEM); if (periods > NR_DESCS_PER_CHANNEL) goto out_err; cdesc = kzalloc(sizeof(struct dw_cyclic_desc), GFP_KERNEL); if (!cdesc) goto out_err; cdesc->desc = kzalloc(sizeof(struct dw_desc *) * periods, GFP_KERNEL); if (!cdesc->desc) goto out_err_alloc; for (i = 0; i < periods; i++) { desc = dwc_desc_get(dwc); if (!desc) goto out_err_desc_get; switch (direction) { case DMA_MEM_TO_DEV: desc->lli.dar = sconfig->dst_addr; desc->lli.sar = buf_addr + (period_len * i); desc->lli.ctllo = (DWC_DEFAULT_CTLLO(chan) | DWC_CTLL_DST_WIDTH(reg_width) | DWC_CTLL_SRC_WIDTH(reg_width) | DWC_CTLL_DST_FIX | DWC_CTLL_SRC_INC | DWC_CTLL_INT_EN); desc->lli.ctllo |= sconfig->device_fc ? DWC_CTLL_FC(DW_DMA_FC_P_M2P) : DWC_CTLL_FC(DW_DMA_FC_D_M2P); break; case DMA_DEV_TO_MEM: desc->lli.dar = buf_addr + (period_len * i); desc->lli.sar = sconfig->src_addr; desc->lli.ctllo = (DWC_DEFAULT_CTLLO(chan) | DWC_CTLL_SRC_WIDTH(reg_width) | DWC_CTLL_DST_WIDTH(reg_width) | DWC_CTLL_DST_INC | DWC_CTLL_SRC_FIX | DWC_CTLL_INT_EN); desc->lli.ctllo |= sconfig->device_fc ? DWC_CTLL_FC(DW_DMA_FC_P_P2M) : DWC_CTLL_FC(DW_DMA_FC_D_P2M); break; default: break; } desc->lli.ctlhi = (period_len >> reg_width); cdesc->desc[i] = desc; if (last) last->lli.llp = desc->txd.phys; last = desc; } /* Let's make a cyclic list */ last->lli.llp = cdesc->desc[0]->txd.phys; dev_dbg(chan2dev(&dwc->chan), "cyclic prepared buf 0x%llx len %zu " "period %zu periods %d\n", (unsigned long long)buf_addr, buf_len, period_len, periods); cdesc->periods = periods; dwc->cdesc = cdesc; return cdesc; out_err_desc_get: while (i--) dwc_desc_put(dwc, cdesc->desc[i]); out_err_alloc: kfree(cdesc); out_err: clear_bit(DW_DMA_IS_CYCLIC, &dwc->flags); return (struct dw_cyclic_desc *)retval; } EXPORT_SYMBOL(dw_dma_cyclic_prep); /** * dw_dma_cyclic_free - free a prepared cyclic DMA transfer * @chan: the DMA channel to free */ void dw_dma_cyclic_free(struct dma_chan *chan) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); struct dw_dma *dw = to_dw_dma(dwc->chan.device); struct dw_cyclic_desc *cdesc = dwc->cdesc; int i; unsigned long flags; dev_dbg(chan2dev(&dwc->chan), "%s\n", __func__); if (!cdesc) return; spin_lock_irqsave(&dwc->lock, flags); dwc_chan_disable(dw, dwc); dma_writel(dw, CLEAR.ERROR, dwc->mask); dma_writel(dw, CLEAR.XFER, dwc->mask); spin_unlock_irqrestore(&dwc->lock, flags); for (i = 0; i < cdesc->periods; i++) dwc_desc_put(dwc, cdesc->desc[i]); kfree(cdesc->desc); kfree(cdesc); clear_bit(DW_DMA_IS_CYCLIC, &dwc->flags); } EXPORT_SYMBOL(dw_dma_cyclic_free); /*----------------------------------------------------------------------*/ static void dw_dma_off(struct dw_dma *dw) { int i; dma_writel(dw, CFG, 0); channel_clear_bit(dw, MASK.XFER, dw->all_chan_mask); channel_clear_bit(dw, MASK.SRC_TRAN, dw->all_chan_mask); channel_clear_bit(dw, MASK.DST_TRAN, dw->all_chan_mask); channel_clear_bit(dw, MASK.ERROR, dw->all_chan_mask); while (dma_readl(dw, CFG) & DW_CFG_DMA_EN) cpu_relax(); for (i = 0; i < dw->dma.chancnt; i++) dw->chan[i].initialized = false; } #ifdef CONFIG_OF static struct dw_dma_platform_data * dw_dma_parse_dt(struct platform_device *pdev) { struct device_node *np = pdev->dev.of_node; struct dw_dma_platform_data *pdata; u32 tmp, arr[4]; if (!np) { dev_err(&pdev->dev, "Missing DT data\n"); return NULL; } pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); if (!pdata) return NULL; if (of_property_read_u32(np, "dma-channels", &pdata->nr_channels)) return NULL; if (of_property_read_bool(np, "is_private")) pdata->is_private = true; if (!of_property_read_u32(np, "chan_allocation_order", &tmp)) pdata->chan_allocation_order = (unsigned char)tmp; if (!of_property_read_u32(np, "chan_priority", &tmp)) pdata->chan_priority = tmp; if (!of_property_read_u32(np, "block_size", &tmp)) pdata->block_size = tmp; if (!of_property_read_u32(np, "dma-masters", &tmp)) { if (tmp > 4) return NULL; pdata->nr_masters = tmp; } if (!of_property_read_u32_array(np, "data_width", arr, pdata->nr_masters)) for (tmp = 0; tmp < pdata->nr_masters; tmp++) pdata->data_width[tmp] = arr[tmp]; return pdata; } #else static inline struct dw_dma_platform_data * dw_dma_parse_dt(struct platform_device *pdev) { return NULL; } #endif static int dw_probe(struct platform_device *pdev) { struct dw_dma_platform_data *pdata; struct resource *io; struct dw_dma *dw; size_t size; void __iomem *regs; bool autocfg; unsigned int dw_params; unsigned int nr_channels; unsigned int max_blk_size = 0; int irq; int err; int i; io = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!io) return -EINVAL; irq = platform_get_irq(pdev, 0); if (irq < 0) return irq; regs = devm_ioremap_resource(&pdev->dev, io); if (IS_ERR(regs)) return PTR_ERR(regs); /* Apply default dma_mask if needed */ if (!pdev->dev.dma_mask) { pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask; pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32); } dw_params = dma_read_byaddr(regs, DW_PARAMS); autocfg = dw_params >> DW_PARAMS_EN & 0x1; dev_dbg(&pdev->dev, "DW_PARAMS: 0x%08x\n", dw_params); pdata = dev_get_platdata(&pdev->dev); if (!pdata) pdata = dw_dma_parse_dt(pdev); if (!pdata && autocfg) { pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); if (!pdata) return -ENOMEM; /* Fill platform data with the default values */ pdata->is_private = true; pdata->chan_allocation_order = CHAN_ALLOCATION_ASCENDING; pdata->chan_priority = CHAN_PRIORITY_ASCENDING; } else if (!pdata || pdata->nr_channels > DW_DMA_MAX_NR_CHANNELS) return -EINVAL; if (autocfg) nr_channels = (dw_params >> DW_PARAMS_NR_CHAN & 0x7) + 1; else nr_channels = pdata->nr_channels; size = sizeof(struct dw_dma) + nr_channels * sizeof(struct dw_dma_chan); dw = devm_kzalloc(&pdev->dev, size, GFP_KERNEL); if (!dw) return -ENOMEM; dw->clk = devm_clk_get(&pdev->dev, "hclk"); if (IS_ERR(dw->clk)) return PTR_ERR(dw->clk); clk_prepare_enable(dw->clk); dw->regs = regs; /* Get hardware configuration parameters */ if (autocfg) { max_blk_size = dma_readl(dw, MAX_BLK_SIZE); dw->nr_masters = (dw_params >> DW_PARAMS_NR_MASTER & 3) + 1; for (i = 0; i < dw->nr_masters; i++) { dw->data_width[i] = (dw_params >> DW_PARAMS_DATA_WIDTH(i) & 3) + 2; } } else { dw->nr_masters = pdata->nr_masters; memcpy(dw->data_width, pdata->data_width, 4); } /* Calculate all channel mask before DMA setup */ dw->all_chan_mask = (1 << nr_channels) - 1; /* Force dma off, just in case */ dw_dma_off(dw); /* Disable BLOCK interrupts as well */ channel_clear_bit(dw, MASK.BLOCK, dw->all_chan_mask); err = devm_request_irq(&pdev->dev, irq, dw_dma_interrupt, 0, "dw_dmac", dw); if (err) return err; platform_set_drvdata(pdev, dw); /* Create a pool of consistent memory blocks for hardware descriptors */ dw->desc_pool = dmam_pool_create("dw_dmac_desc_pool", &pdev->dev, sizeof(struct dw_desc), 4, 0); if (!dw->desc_pool) { dev_err(&pdev->dev, "No memory for descriptors dma pool\n"); return -ENOMEM; } tasklet_init(&dw->tasklet, dw_dma_tasklet, (unsigned long)dw); INIT_LIST_HEAD(&dw->dma.channels); for (i = 0; i < nr_channels; i++) { struct dw_dma_chan *dwc = &dw->chan[i]; int r = nr_channels - i - 1; dwc->chan.device = &dw->dma; dma_cookie_init(&dwc->chan); if (pdata->chan_allocation_order == CHAN_ALLOCATION_ASCENDING) list_add_tail(&dwc->chan.device_node, &dw->dma.channels); else list_add(&dwc->chan.device_node, &dw->dma.channels); /* 7 is highest priority & 0 is lowest. */ if (pdata->chan_priority == CHAN_PRIORITY_ASCENDING) dwc->priority = r; else dwc->priority = i; dwc->ch_regs = &__dw_regs(dw)->CHAN[i]; spin_lock_init(&dwc->lock); dwc->mask = 1 << i; INIT_LIST_HEAD(&dwc->active_list); INIT_LIST_HEAD(&dwc->queue); INIT_LIST_HEAD(&dwc->free_list); channel_clear_bit(dw, CH_EN, dwc->mask); dwc->direction = DMA_TRANS_NONE; dwc->request_line = ~0; /* Hardware configuration */ if (autocfg) { unsigned int dwc_params; dwc_params = dma_read_byaddr(regs + r * sizeof(u32), DWC_PARAMS); dev_dbg(&pdev->dev, "DWC_PARAMS[%d]: 0x%08x\n", i, dwc_params); /* Decode maximum block size for given channel. The * stored 4 bit value represents blocks from 0x00 for 3 * up to 0x0a for 4095. */ dwc->block_size = (4 << ((max_blk_size >> 4 * i) & 0xf)) - 1; dwc->nollp = (dwc_params >> DWC_PARAMS_MBLK_EN & 0x1) == 0; } else { dwc->block_size = pdata->block_size; /* Check if channel supports multi block transfer */ channel_writel(dwc, LLP, 0xfffffffc); dwc->nollp = (channel_readl(dwc, LLP) & 0xfffffffc) == 0; channel_writel(dwc, LLP, 0); } } /* Clear all interrupts on all channels. */ dma_writel(dw, CLEAR.XFER, dw->all_chan_mask); dma_writel(dw, CLEAR.BLOCK, dw->all_chan_mask); dma_writel(dw, CLEAR.SRC_TRAN, dw->all_chan_mask); dma_writel(dw, CLEAR.DST_TRAN, dw->all_chan_mask); dma_writel(dw, CLEAR.ERROR, dw->all_chan_mask); dma_cap_set(DMA_MEMCPY, dw->dma.cap_mask); dma_cap_set(DMA_SLAVE, dw->dma.cap_mask); if (pdata->is_private) dma_cap_set(DMA_PRIVATE, dw->dma.cap_mask); dw->dma.dev = &pdev->dev; dw->dma.device_alloc_chan_resources = dwc_alloc_chan_resources; dw->dma.device_free_chan_resources = dwc_free_chan_resources; dw->dma.device_prep_dma_memcpy = dwc_prep_dma_memcpy; dw->dma.device_prep_slave_sg = dwc_prep_slave_sg; dw->dma.device_control = dwc_control; dw->dma.device_tx_status = dwc_tx_status; dw->dma.device_issue_pending = dwc_issue_pending; dma_writel(dw, CFG, DW_CFG_DMA_EN); dev_info(&pdev->dev, "DesignWare DMA Controller, %d channels\n", nr_channels); dma_async_device_register(&dw->dma); if (pdev->dev.of_node) { err = of_dma_controller_register(pdev->dev.of_node, dw_dma_of_xlate, dw); if (err) dev_err(&pdev->dev, "could not register of_dma_controller\n"); } if (ACPI_HANDLE(&pdev->dev)) dw_dma_acpi_controller_register(dw); return 0; } static int dw_remove(struct platform_device *pdev) { struct dw_dma *dw = platform_get_drvdata(pdev); struct dw_dma_chan *dwc, *_dwc; if (pdev->dev.of_node) of_dma_controller_free(pdev->dev.of_node); dw_dma_off(dw); dma_async_device_unregister(&dw->dma); tasklet_kill(&dw->tasklet); list_for_each_entry_safe(dwc, _dwc, &dw->dma.channels, chan.device_node) { list_del(&dwc->chan.device_node); channel_clear_bit(dw, CH_EN, dwc->mask); } return 0; } static void dw_shutdown(struct platform_device *pdev) { struct dw_dma *dw = platform_get_drvdata(pdev); dw_dma_off(dw); clk_disable_unprepare(dw->clk); } static int dw_suspend_noirq(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct dw_dma *dw = platform_get_drvdata(pdev); dw_dma_off(dw); clk_disable_unprepare(dw->clk); return 0; } static int dw_resume_noirq(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct dw_dma *dw = platform_get_drvdata(pdev); clk_prepare_enable(dw->clk); dma_writel(dw, CFG, DW_CFG_DMA_EN); return 0; } static const struct dev_pm_ops dw_dev_pm_ops = { .suspend_noirq = dw_suspend_noirq, .resume_noirq = dw_resume_noirq, .freeze_noirq = dw_suspend_noirq, .thaw_noirq = dw_resume_noirq, .restore_noirq = dw_resume_noirq, .poweroff_noirq = dw_suspend_noirq, }; #ifdef CONFIG_OF static const struct of_device_id dw_dma_of_id_table[] = { { .compatible = "snps,dma-spear1340" }, {} }; MODULE_DEVICE_TABLE(of, dw_dma_of_id_table); #endif #ifdef CONFIG_ACPI static const struct acpi_device_id dw_dma_acpi_id_table[] = { { "INTL9C60", 0 }, { } }; #endif static struct platform_driver dw_driver = { .probe = dw_probe, .remove = dw_remove, .shutdown = dw_shutdown, .driver = { .name = "dw_dmac", .pm = &dw_dev_pm_ops, .of_match_table = of_match_ptr(dw_dma_of_id_table), .acpi_match_table = ACPI_PTR(dw_dma_acpi_id_table), }, }; static int __init dw_init(void) { return platform_driver_register(&dw_driver); } subsys_initcall(dw_init); static void __exit dw_exit(void) { platform_driver_unregister(&dw_driver); } module_exit(dw_exit); MODULE_LICENSE("GPL v2"); MODULE_DESCRIPTION("Synopsys DesignWare DMA Controller driver"); MODULE_AUTHOR("Haavard Skinnemoen (Atmel)"); MODULE_AUTHOR("Viresh Kumar ");