| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Andy Shevchenko | 3432 | 52.97% | 71 | 59.66% |
| Håvard Skinnemoen | 1508 | 23.28% | 1 | 0.84% |
| Viresh Kumar | 425 | 6.56% | 15 | 12.61% |
| Hans-Christian Noren Egtvedt | 376 | 5.80% | 1 | 0.84% |
| Christian Lamparter | 200 | 3.09% | 1 | 0.84% |
| Serge Semin | 176 | 2.72% | 5 | 4.20% |
| Måns Rullgård | 163 | 2.52% | 4 | 3.36% |
| Dan J Williams | 65 | 1.00% | 2 | 1.68% |
| Dave Jiang | 28 | 0.43% | 1 | 0.84% |
| Jamie Iles | 28 | 0.43% | 3 | 2.52% |
| Maxime Ripard | 25 | 0.39% | 1 | 0.84% |
| Arnd Bergmann | 24 | 0.37% | 2 | 1.68% |
| Russell King | 11 | 0.17% | 3 | 2.52% |
| Eugeniy Paltsev | 5 | 0.08% | 1 | 0.84% |
| Thierry Reding | 3 | 0.05% | 1 | 0.84% |
| Jarkko Nikula | 3 | 0.05% | 1 | 0.84% |
| Linus Walleij | 3 | 0.05% | 2 | 1.68% |
| Atsushi Nemoto | 1 | 0.02% | 1 | 0.84% |
| Barry Song | 1 | 0.02% | 1 | 0.84% |
| Jean Delvare | 1 | 0.02% | 1 | 0.84% |
| Kay Sievers | 1 | 0.02% | 1 | 0.84% |
| Total | 6479 | 119 |
// SPDX-License-Identifier: GPL-2.0 /* * Core driver for the Synopsys DesignWare DMA Controller * * Copyright (C) 2007-2008 Atmel Corporation * Copyright (C) 2010-2011 ST Microelectronics * Copyright (C) 2013 Intel Corporation */ #include <linux/bitops.h> #include <linux/delay.h> #include <linux/dmaengine.h> #include <linux/dma-mapping.h> #include <linux/dmapool.h> #include <linux/err.h> #include <linux/init.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/mm.h> #include <linux/module.h> #include <linux/slab.h> #include <linux/pm_runtime.h> #include "../dmaengine.h" #include "internal.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 been tested with the Atmel AT32AP7000, which does not * support descriptor writeback. */ /* The set of bus widths supported by the DMA controller */ #define DW_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) /*----------------------------------------------------------------------*/ static struct device *chan2dev(struct dma_chan *chan) { return &chan->dev->device; } static struct dw_desc *dwc_first_active(struct dw_dma_chan *dwc) { return to_dw_desc(dwc->active_list.next); } 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. */ list_add_tail(&desc->desc_node, &dwc->queue); spin_unlock_irqrestore(&dwc->lock, flags); dev_vdbg(chan2dev(tx->chan), "%s: queued %u\n", __func__, desc->txd.cookie); return cookie; } static struct dw_desc *dwc_desc_get(struct dw_dma_chan *dwc) { struct dw_dma *dw = to_dw_dma(dwc->chan.device); struct dw_desc *desc; dma_addr_t phys; desc = dma_pool_zalloc(dw->desc_pool, GFP_ATOMIC, &phys); if (!desc) return NULL; dwc->descs_allocated++; INIT_LIST_HEAD(&desc->tx_list); dma_async_tx_descriptor_init(&desc->txd, &dwc->chan); desc->txd.tx_submit = dwc_tx_submit; desc->txd.flags = DMA_CTRL_ACK; desc->txd.phys = phys; return desc; } static void dwc_desc_put(struct dw_dma_chan *dwc, struct dw_desc *desc) { struct dw_dma *dw = to_dw_dma(dwc->chan.device); struct dw_desc *child, *_next; if (unlikely(!desc)) return; list_for_each_entry_safe(child, _next, &desc->tx_list, desc_node) { list_del(&child->desc_node); dma_pool_free(dw->desc_pool, child, child->txd.phys); dwc->descs_allocated--; } dma_pool_free(dw->desc_pool, desc, desc->txd.phys); dwc->descs_allocated--; } static void dwc_initialize(struct dw_dma_chan *dwc) { struct dw_dma *dw = to_dw_dma(dwc->chan.device); dw->initialize_chan(dwc); /* Enable interrupts */ channel_set_bit(dw, MASK.XFER, dwc->mask); channel_set_bit(dw, MASK.ERROR, dwc->mask); } /*----------------------------------------------------------------------*/ 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 = lli_read(desc, ctllo) | DWC_CTLL_INT_EN; channel_writel(dwc, SAR, lli_read(desc, sar)); channel_writel(dwc, DAR, lli_read(desc, dar)); channel_writel(dwc, CTL_LO, ctllo); channel_writel(dwc, CTL_HI, lli_read(desc, 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); u8 lms = DWC_LLP_LMS(dwc->dws.m_master); unsigned long was_soft_llp; /* ASSERT: channel is idle */ if (dma_readl(dw, CH_EN) & dwc->mask) { dev_err(chan2dev(&dwc->chan), "%s: BUG: Attempted to start non-idle channel\n", __func__); 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); first->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 | lms); 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_dostart_first_queued(struct dw_dma_chan *dwc) { struct dw_desc *desc; if (list_empty(&dwc->queue)) return; list_move(dwc->queue.next, &dwc->active_list); desc = dwc_first_active(dwc); dev_vdbg(chan2dev(&dwc->chan), "%s: started %u\n", __func__, desc->txd.cookie); dwc_dostart(dwc, desc); } /*----------------------------------------------------------------------*/ static void dwc_descriptor_complete(struct dw_dma_chan *dwc, struct dw_desc *desc, bool callback_required) { struct dma_async_tx_descriptor *txd = &desc->txd; struct dw_desc *child; unsigned long flags; struct dmaengine_desc_callback cb; dev_vdbg(chan2dev(&dwc->chan), "descriptor %u complete\n", txd->cookie); spin_lock_irqsave(&dwc->lock, flags); dma_cookie_complete(txd); if (callback_required) dmaengine_desc_get_callback(txd, &cb); else memset(&cb, 0, sizeof(cb)); /* async_tx_ack */ list_for_each_entry(child, &desc->tx_list, desc_node) async_tx_ack(&child->txd); async_tx_ack(&desc->txd); dwc_desc_put(dwc, desc); spin_unlock_irqrestore(&dwc->lock, flags); dmaengine_desc_callback_invoke(&cb, NULL); } 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); dwc_dostart_first_queued(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) { struct dw_dma *dw = to_dw_dma(dwc->chan.device); u32 ctlhi = channel_readl(dwc, CTL_HI); u32 ctllo = channel_readl(dwc, CTL_LO); return dw->block2bytes(dwc, ctlhi, 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 residue to reflect last sent descriptor */ if (active == head->next) desc->residue -= desc->len; else desc->residue -= to_dw_desc(active->prev)->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); } spin_unlock_irqrestore(&dwc->lock, flags); dwc_complete_all(dw, dwc); return; } if (list_empty(&dwc->active_list)) { 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=%pad\n", __func__, &llp); list_for_each_entry_safe(desc, _desc, &dwc->active_list, desc_node) { /* Initial residue value */ desc->residue = desc->total_len; /* Check first descriptors addr */ if (desc->txd.phys == DWC_LLP_LOC(llp)) { spin_unlock_irqrestore(&dwc->lock, flags); return; } /* Check first descriptors llp */ if (lli_read(desc, llp) == llp) { /* This one is currently in progress */ desc->residue -= dwc_get_sent(dwc); spin_unlock_irqrestore(&dwc->lock, flags); return; } desc->residue -= desc->len; list_for_each_entry(child, &desc->tx_list, desc_node) { if (lli_read(child, llp) == llp) { /* Currently in progress */ desc->residue -= dwc_get_sent(dwc); spin_unlock_irqrestore(&dwc->lock, flags); return; } desc->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); dwc_dostart_first_queued(dwc); spin_unlock_irqrestore(&dwc->lock, flags); } static inline void dwc_dump_lli(struct dw_dma_chan *dwc, struct dw_desc *desc) { dev_crit(chan2dev(&dwc->chan), " desc: s0x%x d0x%x l0x%x c0x%x:%x\n", lli_read(desc, sar), lli_read(desc, dar), lli_read(desc, llp), lli_read(desc, ctlhi), lli_read(desc, 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); list_for_each_entry(child, &bad_desc->tx_list, desc_node) dwc_dump_lli(dwc, child); spin_unlock_irqrestore(&dwc->lock, flags); /* Pretend the descriptor completed successfully */ dwc_descriptor_complete(dwc, bad_desc, true); } 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; unsigned 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)) dev_vdbg(dw->dma.dev, "Cyclic xfer is not implemented\n"); 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; /* Check if we have any interrupt from the DMAC which is not in use */ if (!dw->in_use) return IRQ_NONE; status = dma_readl(dw, STATUS_INT); dev_vdbg(dw->dma.dev, "%s: status=0x%x\n", __func__, status); /* Check if we have any interrupt from the DMAC */ if (!status) return IRQ_NONE; /* * 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.BLOCK, 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.BLOCK, (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 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; u8 m_master = dwc->dws.m_master; unsigned int src_width; unsigned int dst_width; unsigned int data_width = dw->pdata->data_width[m_master]; u32 ctllo, ctlhi; u8 lms = DWC_LLP_LMS(m_master); dev_vdbg(chan2dev(chan), "%s: d%pad s%pad l0x%zx f0x%lx\n", __func__, &dest, &src, len, flags); if (unlikely(!len)) { dev_dbg(chan2dev(chan), "%s: length is zero!\n", __func__); return NULL; } dwc->direction = DMA_MEM_TO_MEM; src_width = dst_width = __ffs(data_width | src | dest | len); ctllo = dw->prepare_ctllo(dwc) | 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) { desc = dwc_desc_get(dwc); if (!desc) goto err_desc_get; ctlhi = dw->bytes2block(dwc, len - offset, src_width, &xfer_count); lli_write(desc, sar, src + offset); lli_write(desc, dar, dest + offset); lli_write(desc, ctllo, ctllo); lli_write(desc, ctlhi, ctlhi); desc->len = xfer_count; if (!first) { first = desc; } else { lli_write(prev, llp, desc->txd.phys | lms); list_add_tail(&desc->desc_node, &first->tx_list); } prev = desc; } if (flags & DMA_PREP_INTERRUPT) /* Trigger interrupt after last block */ lli_set(prev, ctllo, DWC_CTLL_INT_EN); prev->lli.llp = 0; lli_clear(prev, ctllo, DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN); 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, ctlhi; u8 m_master = dwc->dws.m_master; u8 lms = DWC_LLP_LMS(m_master); dma_addr_t reg; unsigned int reg_width; unsigned int mem_width; unsigned int data_width = dw->pdata->data_width[m_master]; 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 = __ffs(sconfig->dst_addr_width); reg = sconfig->dst_addr; ctllo = dw->prepare_ctllo(dwc) | 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); for_each_sg(sgl, sg, sg_len, i) { struct dw_desc *desc; u32 len, mem; size_t dlen; mem = sg_dma_address(sg); len = sg_dma_len(sg); mem_width = __ffs(data_width | mem | len); slave_sg_todev_fill_desc: desc = dwc_desc_get(dwc); if (!desc) goto err_desc_get; ctlhi = dw->bytes2block(dwc, len, mem_width, &dlen); lli_write(desc, sar, mem); lli_write(desc, dar, reg); lli_write(desc, ctlhi, ctlhi); lli_write(desc, ctllo, ctllo | DWC_CTLL_SRC_WIDTH(mem_width)); desc->len = dlen; if (!first) { first = desc; } else { lli_write(prev, llp, desc->txd.phys | lms); list_add_tail(&desc->desc_node, &first->tx_list); } prev = desc; mem += dlen; len -= dlen; total_len += dlen; if (len) goto slave_sg_todev_fill_desc; } break; case DMA_DEV_TO_MEM: reg_width = __ffs(sconfig->src_addr_width); reg = sconfig->src_addr; ctllo = dw->prepare_ctllo(dwc) | 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); for_each_sg(sgl, sg, sg_len, i) { struct dw_desc *desc; u32 len, mem; size_t dlen; mem = sg_dma_address(sg); len = sg_dma_len(sg); slave_sg_fromdev_fill_desc: desc = dwc_desc_get(dwc); if (!desc) goto err_desc_get; ctlhi = dw->bytes2block(dwc, len, reg_width, &dlen); lli_write(desc, sar, reg); lli_write(desc, dar, mem); lli_write(desc, ctlhi, ctlhi); mem_width = __ffs(data_width | mem | dlen); lli_write(desc, ctllo, ctllo | DWC_CTLL_DST_WIDTH(mem_width)); desc->len = dlen; if (!first) { first = desc; } else { lli_write(prev, llp, desc->txd.phys | lms); list_add_tail(&desc->desc_node, &first->tx_list); } prev = desc; mem += dlen; len -= dlen; 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 */ lli_set(prev, ctllo, DWC_CTLL_INT_EN); prev->lli.llp = 0; lli_clear(prev, ctllo, DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN); first->total_len = total_len; return &first->txd; err_desc_get: dev_err(chan2dev(chan), "not enough descriptors available. Direction %d\n", direction); dwc_desc_put(dwc, first); return NULL; } bool dw_dma_filter(struct dma_chan *chan, void *param) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); struct dw_dma_slave *dws = param; if (dws->dma_dev != chan->device->dev) return false; /* We have to copy data since dws can be temporary storage */ memcpy(&dwc->dws, dws, sizeof(struct dw_dma_slave)); return true; } EXPORT_SYMBOL_GPL(dw_dma_filter); static int dwc_config(struct dma_chan *chan, struct dma_slave_config *sconfig) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); struct dw_dma *dw = to_dw_dma(chan->device); memcpy(&dwc->dma_sconfig, sconfig, sizeof(*sconfig)); dwc->dma_sconfig.src_maxburst = clamp(dwc->dma_sconfig.src_maxburst, 0U, dwc->max_burst); dwc->dma_sconfig.dst_maxburst = clamp(dwc->dma_sconfig.dst_maxburst, 0U, dwc->max_burst); dw->encode_maxburst(dwc, &dwc->dma_sconfig.src_maxburst); dw->encode_maxburst(dwc, &dwc->dma_sconfig.dst_maxburst); return 0; } static void dwc_chan_pause(struct dw_dma_chan *dwc, bool drain) { struct dw_dma *dw = to_dw_dma(dwc->chan.device); unsigned int count = 20; /* timeout iterations */ dw->suspend_chan(dwc, drain); while (!(channel_readl(dwc, CFG_LO) & DWC_CFGL_FIFO_EMPTY) && count--) udelay(2); set_bit(DW_DMA_IS_PAUSED, &dwc->flags); } static int dwc_pause(struct dma_chan *chan) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); unsigned long flags; spin_lock_irqsave(&dwc->lock, flags); dwc_chan_pause(dwc, false); spin_unlock_irqrestore(&dwc->lock, flags); return 0; } static inline void dwc_chan_resume(struct dw_dma_chan *dwc, bool drain) { struct dw_dma *dw = to_dw_dma(dwc->chan.device); dw->resume_chan(dwc, drain); clear_bit(DW_DMA_IS_PAUSED, &dwc->flags); } static int dwc_resume(struct dma_chan *chan) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); unsigned long flags; spin_lock_irqsave(&dwc->lock, flags); if (test_bit(DW_DMA_IS_PAUSED, &dwc->flags)) dwc_chan_resume(dwc, false); spin_unlock_irqrestore(&dwc->lock, flags); return 0; } static int dwc_terminate_all(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); spin_lock_irqsave(&dwc->lock, flags); clear_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags); dwc_chan_pause(dwc, true); dwc_chan_disable(dw, dwc); dwc_chan_resume(dwc, true); /* 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); return 0; } static struct dw_desc *dwc_find_desc(struct dw_dma_chan *dwc, dma_cookie_t c) { struct dw_desc *desc; list_for_each_entry(desc, &dwc->active_list, desc_node) if (desc->txd.cookie == c) return desc; return NULL; } static u32 dwc_get_residue(struct dw_dma_chan *dwc, dma_cookie_t cookie) { struct dw_desc *desc; unsigned long flags; u32 residue; spin_lock_irqsave(&dwc->lock, flags); desc = dwc_find_desc(dwc, cookie); if (desc) { if (desc == dwc_first_active(dwc)) { residue = desc->residue; if (test_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags) && residue) residue -= dwc_get_sent(dwc); } else { residue = desc->total_len; } } else { residue = 0; } 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_COMPLETE) return ret; dwc_scan_descriptors(to_dw_dma(chan->device), dwc); ret = dma_cookie_status(chan, cookie, txstate); if (ret == DMA_COMPLETE) return ret; dma_set_residue(txstate, dwc_get_residue(dwc, cookie)); if (test_bit(DW_DMA_IS_PAUSED, &dwc->flags) && ret == DMA_IN_PROGRESS) return DMA_PAUSED; return ret; } static void dwc_issue_pending(struct dma_chan *chan) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); unsigned long flags; spin_lock_irqsave(&dwc->lock, flags); if (list_empty(&dwc->active_list)) dwc_dostart_first_queued(dwc); spin_unlock_irqrestore(&dwc->lock, flags); } /*----------------------------------------------------------------------*/ void do_dw_dma_off(struct dw_dma *dw) { dma_writel(dw, CFG, 0); channel_clear_bit(dw, MASK.XFER, dw->all_chan_mask); channel_clear_bit(dw, MASK.BLOCK, 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(); } void do_dw_dma_on(struct dw_dma *dw) { dma_writel(dw, CFG, DW_CFG_DMA_EN); } 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); 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. */ /* * We need controller-specific data to set up slave transfers. */ if (chan->private && !dw_dma_filter(chan, chan->private)) { dev_warn(chan2dev(chan), "Wrong controller-specific data\n"); return -EINVAL; } /* Enable controller here if needed */ if (!dw->in_use) do_dw_dma_on(dw); dw->in_use |= dwc->mask; return 0; } 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); unsigned long flags; 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); /* Clear custom channel configuration */ memset(&dwc->dws, 0, sizeof(struct dw_dma_slave)); /* Disable interrupts */ channel_clear_bit(dw, MASK.XFER, dwc->mask); channel_clear_bit(dw, MASK.BLOCK, dwc->mask); channel_clear_bit(dw, MASK.ERROR, dwc->mask); spin_unlock_irqrestore(&dwc->lock, flags); /* Disable controller in case it was a last user */ dw->in_use &= ~dwc->mask; if (!dw->in_use) do_dw_dma_off(dw); dev_vdbg(chan2dev(chan), "%s: done\n", __func__); } static void dwc_caps(struct dma_chan *chan, struct dma_slave_caps *caps) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); caps->max_burst = dwc->max_burst; /* * It might be crucial for some devices to have the hardware * accelerated multi-block transfers supported, aka LLPs in DW DMAC * notation. So if LLPs are supported then max_sg_burst is set to * zero which means unlimited number of SG entries can be handled in a * single DMA transaction, otherwise it's just one SG entry. */ if (dwc->nollp) caps->max_sg_burst = 1; else caps->max_sg_burst = 0; } int do_dma_probe(struct dw_dma_chip *chip) { struct dw_dma *dw = chip->dw; struct dw_dma_platform_data *pdata; bool autocfg = false; unsigned int dw_params; unsigned int i; int err; dw->pdata = devm_kzalloc(chip->dev, sizeof(*dw->pdata), GFP_KERNEL); if (!dw->pdata) return -ENOMEM; dw->regs = chip->regs; pm_runtime_get_sync(chip->dev); if (!chip->pdata) { dw_params = dma_readl(dw, DW_PARAMS); dev_dbg(chip->dev, "DW_PARAMS: 0x%08x\n", dw_params); autocfg = dw_params >> DW_PARAMS_EN & 1; if (!autocfg) { err = -EINVAL; goto err_pdata; } /* Reassign the platform data pointer */ pdata = dw->pdata; /* Get hardware configuration parameters */ pdata->nr_channels = (dw_params >> DW_PARAMS_NR_CHAN & 7) + 1; pdata->nr_masters = (dw_params >> DW_PARAMS_NR_MASTER & 3) + 1; for (i = 0; i < pdata->nr_masters; i++) { pdata->data_width[i] = 4 << (dw_params >> DW_PARAMS_DATA_WIDTH(i) & 3); } pdata->block_size = dma_readl(dw, MAX_BLK_SIZE); /* Fill platform data with the default values */ pdata->chan_allocation_order = CHAN_ALLOCATION_ASCENDING; pdata->chan_priority = CHAN_PRIORITY_ASCENDING; } else if (chip->pdata->nr_channels > DW_DMA_MAX_NR_CHANNELS) { err = -EINVAL; goto err_pdata; } else { memcpy(dw->pdata, chip->pdata, sizeof(*dw->pdata)); /* Reassign the platform data pointer */ pdata = dw->pdata; } dw->chan = devm_kcalloc(chip->dev, pdata->nr_channels, sizeof(*dw->chan), GFP_KERNEL); if (!dw->chan) { err = -ENOMEM; goto err_pdata; } /* Calculate all channel mask before DMA setup */ dw->all_chan_mask = (1 << pdata->nr_channels) - 1; /* Force dma off, just in case */ dw->disable(dw); /* Device and instance ID for IRQ and DMA pool */ dw->set_device_name(dw, chip->id); /* Create a pool of consistent memory blocks for hardware descriptors */ dw->desc_pool = dmam_pool_create(dw->name, chip->dev, sizeof(struct dw_desc), 4, 0); if (!dw->desc_pool) { dev_err(chip->dev, "No memory for descriptors dma pool\n"); err = -ENOMEM; goto err_pdata; } tasklet_init(&dw->tasklet, dw_dma_tasklet, (unsigned long)dw); err = request_irq(chip->irq, dw_dma_interrupt, IRQF_SHARED, dw->name, dw); if (err) goto err_pdata; INIT_LIST_HEAD(&dw->dma.channels); for (i = 0; i < pdata->nr_channels; i++) { struct dw_dma_chan *dwc = &dw->chan[i]; 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 = pdata->nr_channels - i - 1; 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); channel_clear_bit(dw, CH_EN, dwc->mask); dwc->direction = DMA_TRANS_NONE; /* Hardware configuration */ if (autocfg) { unsigned int r = DW_DMA_MAX_NR_CHANNELS - i - 1; void __iomem *addr = &__dw_regs(dw)->DWC_PARAMS[r]; unsigned int dwc_params = readl(addr); dev_dbg(chip->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 << ((pdata->block_size >> 4 * i) & 0xf)) - 1; /* * According to the DW DMA databook the true scatter- * gether LLPs aren't available if either multi-block * config is disabled (CHx_MULTI_BLK_EN == 0) or the * LLP register is hard-coded to zeros * (CHx_HC_LLP == 1). */ dwc->nollp = (dwc_params >> DWC_PARAMS_MBLK_EN & 0x1) == 0 || (dwc_params >> DWC_PARAMS_HC_LLP & 0x1) == 1; dwc->max_burst = (0x4 << (dwc_params >> DWC_PARAMS_MSIZE & 0x7)); } else { dwc->block_size = pdata->block_size; dwc->nollp = !pdata->multi_block[i]; dwc->max_burst = pdata->max_burst[i] ?: DW_DMA_MAX_BURST; } } /* 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); /* Set capabilities */ dma_cap_set(DMA_SLAVE, dw->dma.cap_mask); dma_cap_set(DMA_PRIVATE, dw->dma.cap_mask); dma_cap_set(DMA_MEMCPY, dw->dma.cap_mask); dw->dma.dev = chip->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_caps = dwc_caps; dw->dma.device_config = dwc_config; dw->dma.device_pause = dwc_pause; dw->dma.device_resume = dwc_resume; dw->dma.device_terminate_all = dwc_terminate_all; dw->dma.device_tx_status = dwc_tx_status; dw->dma.device_issue_pending = dwc_issue_pending; /* DMA capabilities */ dw->dma.min_burst = DW_DMA_MIN_BURST; dw->dma.max_burst = DW_DMA_MAX_BURST; dw->dma.src_addr_widths = DW_DMA_BUSWIDTHS; dw->dma.dst_addr_widths = DW_DMA_BUSWIDTHS; dw->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV) | BIT(DMA_MEM_TO_MEM); dw->dma.residue_granularity = DMA_RESIDUE_GRANULARITY_BURST; /* * For now there is no hardware with non uniform maximum block size * across all of the device channels, so we set the maximum segment * size as the block size found for the very first channel. */ dma_set_max_seg_size(dw->dma.dev, dw->chan[0].block_size); err = dma_async_device_register(&dw->dma); if (err) goto err_dma_register; dev_info(chip->dev, "DesignWare DMA Controller, %d channels\n", pdata->nr_channels); pm_runtime_put_sync_suspend(chip->dev); return 0; err_dma_register: free_irq(chip->irq, dw); err_pdata: pm_runtime_put_sync_suspend(chip->dev); return err; } int do_dma_remove(struct dw_dma_chip *chip) { struct dw_dma *dw = chip->dw; struct dw_dma_chan *dwc, *_dwc; pm_runtime_get_sync(chip->dev); do_dw_dma_off(dw); dma_async_device_unregister(&dw->dma); free_irq(chip->irq, dw); 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); } pm_runtime_put_sync_suspend(chip->dev); return 0; } int do_dw_dma_disable(struct dw_dma_chip *chip) { struct dw_dma *dw = chip->dw; dw->disable(dw); return 0; } EXPORT_SYMBOL_GPL(do_dw_dma_disable); int do_dw_dma_enable(struct dw_dma_chip *chip) { struct dw_dma *dw = chip->dw; dw->enable(dw); return 0; } EXPORT_SYMBOL_GPL(do_dw_dma_enable); MODULE_LICENSE("GPL v2"); MODULE_DESCRIPTION("Synopsys DesignWare DMA Controller core driver"); MODULE_AUTHOR("Haavard Skinnemoen (Atmel)"); MODULE_AUTHOR("Viresh Kumar <vireshk@kernel.org>");
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