/* * TI EDMA DMA engine driver * * Copyright 2012 Texas Instruments * * 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 version 2. * * This program is distributed "as is" WITHOUT ANY WARRANTY of any * kind, whether express or implied; without even the implied warranty * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "dmaengine.h" #include "virt-dma.h" /* Offsets matching "struct edmacc_param" */ #define PARM_OPT 0x00 #define PARM_SRC 0x04 #define PARM_A_B_CNT 0x08 #define PARM_DST 0x0c #define PARM_SRC_DST_BIDX 0x10 #define PARM_LINK_BCNTRLD 0x14 #define PARM_SRC_DST_CIDX 0x18 #define PARM_CCNT 0x1c #define PARM_SIZE 0x20 /* Offsets for EDMA CC global channel registers and their shadows */ #define SH_ER 0x00 /* 64 bits */ #define SH_ECR 0x08 /* 64 bits */ #define SH_ESR 0x10 /* 64 bits */ #define SH_CER 0x18 /* 64 bits */ #define SH_EER 0x20 /* 64 bits */ #define SH_EECR 0x28 /* 64 bits */ #define SH_EESR 0x30 /* 64 bits */ #define SH_SER 0x38 /* 64 bits */ #define SH_SECR 0x40 /* 64 bits */ #define SH_IER 0x50 /* 64 bits */ #define SH_IECR 0x58 /* 64 bits */ #define SH_IESR 0x60 /* 64 bits */ #define SH_IPR 0x68 /* 64 bits */ #define SH_ICR 0x70 /* 64 bits */ #define SH_IEVAL 0x78 #define SH_QER 0x80 #define SH_QEER 0x84 #define SH_QEECR 0x88 #define SH_QEESR 0x8c #define SH_QSER 0x90 #define SH_QSECR 0x94 #define SH_SIZE 0x200 /* Offsets for EDMA CC global registers */ #define EDMA_REV 0x0000 #define EDMA_CCCFG 0x0004 #define EDMA_QCHMAP 0x0200 /* 8 registers */ #define EDMA_DMAQNUM 0x0240 /* 8 registers (4 on OMAP-L1xx) */ #define EDMA_QDMAQNUM 0x0260 #define EDMA_QUETCMAP 0x0280 #define EDMA_QUEPRI 0x0284 #define EDMA_EMR 0x0300 /* 64 bits */ #define EDMA_EMCR 0x0308 /* 64 bits */ #define EDMA_QEMR 0x0310 #define EDMA_QEMCR 0x0314 #define EDMA_CCERR 0x0318 #define EDMA_CCERRCLR 0x031c #define EDMA_EEVAL 0x0320 #define EDMA_DRAE 0x0340 /* 4 x 64 bits*/ #define EDMA_QRAE 0x0380 /* 4 registers */ #define EDMA_QUEEVTENTRY 0x0400 /* 2 x 16 registers */ #define EDMA_QSTAT 0x0600 /* 2 registers */ #define EDMA_QWMTHRA 0x0620 #define EDMA_QWMTHRB 0x0624 #define EDMA_CCSTAT 0x0640 #define EDMA_M 0x1000 /* global channel registers */ #define EDMA_ECR 0x1008 #define EDMA_ECRH 0x100C #define EDMA_SHADOW0 0x2000 /* 4 shadow regions */ #define EDMA_PARM 0x4000 /* PaRAM entries */ #define PARM_OFFSET(param_no) (EDMA_PARM + ((param_no) << 5)) #define EDMA_DCHMAP 0x0100 /* 64 registers */ /* CCCFG register */ #define GET_NUM_DMACH(x) (x & 0x7) /* bits 0-2 */ #define GET_NUM_PAENTRY(x) ((x & 0x7000) >> 12) /* bits 12-14 */ #define GET_NUM_EVQUE(x) ((x & 0x70000) >> 16) /* bits 16-18 */ #define GET_NUM_REGN(x) ((x & 0x300000) >> 20) /* bits 20-21 */ #define CHMAP_EXIST BIT(24) /* * Max of 20 segments per channel to conserve PaRAM slots * Also note that MAX_NR_SG should be atleast the no.of periods * that are required for ASoC, otherwise DMA prep calls will * fail. Today davinci-pcm is the only user of this driver and * requires atleast 17 slots, so we setup the default to 20. */ #define MAX_NR_SG 20 #define EDMA_MAX_SLOTS MAX_NR_SG #define EDMA_DESCRIPTORS 16 #define EDMA_CHANNEL_ANY -1 /* for edma_alloc_channel() */ #define EDMA_SLOT_ANY -1 /* for edma_alloc_slot() */ #define EDMA_CONT_PARAMS_ANY 1001 #define EDMA_CONT_PARAMS_FIXED_EXACT 1002 #define EDMA_CONT_PARAMS_FIXED_NOT_EXACT 1003 /* PaRAM slots are laid out like this */ struct edmacc_param { u32 opt; u32 src; u32 a_b_cnt; u32 dst; u32 src_dst_bidx; u32 link_bcntrld; u32 src_dst_cidx; u32 ccnt; } __packed; /* fields in edmacc_param.opt */ #define SAM BIT(0) #define DAM BIT(1) #define SYNCDIM BIT(2) #define STATIC BIT(3) #define EDMA_FWID (0x07 << 8) #define TCCMODE BIT(11) #define EDMA_TCC(t) ((t) << 12) #define TCINTEN BIT(20) #define ITCINTEN BIT(21) #define TCCHEN BIT(22) #define ITCCHEN BIT(23) /*ch_status parameter of callback function possible values*/ #define EDMA_DMA_COMPLETE 1 #define EDMA_DMA_CC_ERROR 2 #define EDMA_DMA_TC1_ERROR 3 #define EDMA_DMA_TC2_ERROR 4 struct edma_pset { u32 len; dma_addr_t addr; struct edmacc_param param; }; struct edma_desc { struct virt_dma_desc vdesc; struct list_head node; enum dma_transfer_direction direction; int cyclic; int absync; int pset_nr; struct edma_chan *echan; int processed; /* * The following 4 elements are used for residue accounting. * * - processed_stat: the number of SG elements we have traversed * so far to cover accounting. This is updated directly to processed * during edma_callback and is always <= processed, because processed * refers to the number of pending transfer (programmed to EDMA * controller), where as processed_stat tracks number of transfers * accounted for so far. * * - residue: The amount of bytes we have left to transfer for this desc * * - residue_stat: The residue in bytes of data we have covered * so far for accounting. This is updated directly to residue * during callbacks to keep it current. * * - sg_len: Tracks the length of the current intermediate transfer, * this is required to update the residue during intermediate transfer * completion callback. */ int processed_stat; u32 sg_len; u32 residue; u32 residue_stat; struct edma_pset pset[0]; }; struct edma_cc; struct edma_chan { struct virt_dma_chan vchan; struct list_head node; struct edma_desc *edesc; struct edma_cc *ecc; int ch_num; bool alloced; int slot[EDMA_MAX_SLOTS]; int missed; struct dma_slave_config cfg; }; struct edma_cc { struct device *dev; struct edma_soc_info *info; void __iomem *base; int id; /* eDMA3 resource information */ unsigned num_channels; unsigned num_region; unsigned num_slots; unsigned num_tc; enum dma_event_q default_queue; bool unused_chan_list_done; /* The edma_inuse bit for each PaRAM slot is clear unless the * channel is in use ... by ARM or DSP, for QDMA, or whatever. */ unsigned long *edma_inuse; /* The edma_unused bit for each channel is clear unless * it is not being used on this platform. It uses a bit * of SOC-specific initialization code. */ unsigned long *edma_unused; struct dma_interrupt_data { void (*callback)(unsigned channel, unsigned short ch_status, void *data); void *data; } *intr_data; struct dma_device dma_slave; struct edma_chan *slave_chans; int dummy_slot; }; /* dummy param set used to (re)initialize parameter RAM slots */ static const struct edmacc_param dummy_paramset = { .link_bcntrld = 0xffff, .ccnt = 1, }; static const struct of_device_id edma_of_ids[] = { { .compatible = "ti,edma3", }, {} }; static inline unsigned int edma_read(struct edma_cc *ecc, int offset) { return (unsigned int)__raw_readl(ecc->base + offset); } static inline void edma_write(struct edma_cc *ecc, int offset, int val) { __raw_writel(val, ecc->base + offset); } static inline void edma_modify(struct edma_cc *ecc, int offset, unsigned and, unsigned or) { unsigned val = edma_read(ecc, offset); val &= and; val |= or; edma_write(ecc, offset, val); } static inline void edma_and(struct edma_cc *ecc, int offset, unsigned and) { unsigned val = edma_read(ecc, offset); val &= and; edma_write(ecc, offset, val); } static inline void edma_or(struct edma_cc *ecc, int offset, unsigned or) { unsigned val = edma_read(ecc, offset); val |= or; edma_write(ecc, offset, val); } static inline unsigned int edma_read_array(struct edma_cc *ecc, int offset, int i) { return edma_read(ecc, offset + (i << 2)); } static inline void edma_write_array(struct edma_cc *ecc, int offset, int i, unsigned val) { edma_write(ecc, offset + (i << 2), val); } static inline void edma_modify_array(struct edma_cc *ecc, int offset, int i, unsigned and, unsigned or) { edma_modify(ecc, offset + (i << 2), and, or); } static inline void edma_or_array(struct edma_cc *ecc, int offset, int i, unsigned or) { edma_or(ecc, offset + (i << 2), or); } static inline void edma_or_array2(struct edma_cc *ecc, int offset, int i, int j, unsigned or) { edma_or(ecc, offset + ((i * 2 + j) << 2), or); } static inline void edma_write_array2(struct edma_cc *ecc, int offset, int i, int j, unsigned val) { edma_write(ecc, offset + ((i * 2 + j) << 2), val); } static inline unsigned int edma_shadow0_read(struct edma_cc *ecc, int offset) { return edma_read(ecc, EDMA_SHADOW0 + offset); } static inline unsigned int edma_shadow0_read_array(struct edma_cc *ecc, int offset, int i) { return edma_read(ecc, EDMA_SHADOW0 + offset + (i << 2)); } static inline void edma_shadow0_write(struct edma_cc *ecc, int offset, unsigned val) { edma_write(ecc, EDMA_SHADOW0 + offset, val); } static inline void edma_shadow0_write_array(struct edma_cc *ecc, int offset, int i, unsigned val) { edma_write(ecc, EDMA_SHADOW0 + offset + (i << 2), val); } static inline unsigned int edma_parm_read(struct edma_cc *ecc, int offset, int param_no) { return edma_read(ecc, EDMA_PARM + offset + (param_no << 5)); } static inline void edma_parm_write(struct edma_cc *ecc, int offset, int param_no, unsigned val) { edma_write(ecc, EDMA_PARM + offset + (param_no << 5), val); } static inline void edma_parm_modify(struct edma_cc *ecc, int offset, int param_no, unsigned and, unsigned or) { edma_modify(ecc, EDMA_PARM + offset + (param_no << 5), and, or); } static inline void edma_parm_and(struct edma_cc *ecc, int offset, int param_no, unsigned and) { edma_and(ecc, EDMA_PARM + offset + (param_no << 5), and); } static inline void edma_parm_or(struct edma_cc *ecc, int offset, int param_no, unsigned or) { edma_or(ecc, EDMA_PARM + offset + (param_no << 5), or); } static inline void set_bits(int offset, int len, unsigned long *p) { for (; len > 0; len--) set_bit(offset + (len - 1), p); } static inline void clear_bits(int offset, int len, unsigned long *p) { for (; len > 0; len--) clear_bit(offset + (len - 1), p); } static void edma_map_dmach_to_queue(struct edma_cc *ecc, unsigned ch_no, enum dma_event_q queue_no) { int bit = (ch_no & 0x7) * 4; /* default to low priority queue */ if (queue_no == EVENTQ_DEFAULT) queue_no = ecc->default_queue; queue_no &= 7; edma_modify_array(ecc, EDMA_DMAQNUM, (ch_no >> 3), ~(0x7 << bit), queue_no << bit); } static void edma_assign_priority_to_queue(struct edma_cc *ecc, int queue_no, int priority) { int bit = queue_no * 4; edma_modify(ecc, EDMA_QUEPRI, ~(0x7 << bit), ((priority & 0x7) << bit)); } static void edma_direct_dmach_to_param_mapping(struct edma_cc *ecc) { int i; for (i = 0; i < ecc->num_channels; i++) edma_write_array(ecc, EDMA_DCHMAP, i, (i << 5)); } static int prepare_unused_channel_list(struct device *dev, void *data) { struct platform_device *pdev = to_platform_device(dev); struct edma_cc *ecc = data; int dma_req_min = EDMA_CTLR_CHAN(ecc->id, 0); int dma_req_max = dma_req_min + ecc->num_channels; int i, count; struct of_phandle_args dma_spec; if (dev->of_node) { struct platform_device *dma_pdev; count = of_property_count_strings(dev->of_node, "dma-names"); if (count < 0) return 0; for (i = 0; i < count; i++) { if (of_parse_phandle_with_args(dev->of_node, "dmas", "#dma-cells", i, &dma_spec)) continue; if (!of_match_node(edma_of_ids, dma_spec.np)) { of_node_put(dma_spec.np); continue; } dma_pdev = of_find_device_by_node(dma_spec.np); if (&dma_pdev->dev != ecc->dev) continue; clear_bit(EDMA_CHAN_SLOT(dma_spec.args[0]), ecc->edma_unused); of_node_put(dma_spec.np); } return 0; } /* For non-OF case */ for (i = 0; i < pdev->num_resources; i++) { struct resource *res = &pdev->resource[i]; int dma_req; if (!(res->flags & IORESOURCE_DMA)) continue; dma_req = (int)res->start; if (dma_req >= dma_req_min && dma_req < dma_req_max) clear_bit(EDMA_CHAN_SLOT(pdev->resource[i].start), ecc->edma_unused); } return 0; } static void edma_setup_interrupt(struct edma_cc *ecc, unsigned lch, void (*callback)(unsigned channel, u16 ch_status, void *data), void *data) { lch = EDMA_CHAN_SLOT(lch); if (!callback) edma_shadow0_write_array(ecc, SH_IECR, lch >> 5, BIT(lch & 0x1f)); ecc->intr_data[lch].callback = callback; ecc->intr_data[lch].data = data; if (callback) { edma_shadow0_write_array(ecc, SH_ICR, lch >> 5, BIT(lch & 0x1f)); edma_shadow0_write_array(ecc, SH_IESR, lch >> 5, BIT(lch & 0x1f)); } } /* * paRAM management functions */ /** * edma_write_slot - write parameter RAM data for slot * @ecc: pointer to edma_cc struct * @slot: number of parameter RAM slot being modified * @param: data to be written into parameter RAM slot * * Use this to assign all parameters of a transfer at once. This * allows more efficient setup of transfers than issuing multiple * calls to set up those parameters in small pieces, and provides * complete control over all transfer options. */ static void edma_write_slot(struct edma_cc *ecc, unsigned slot, const struct edmacc_param *param) { slot = EDMA_CHAN_SLOT(slot); if (slot >= ecc->num_slots) return; memcpy_toio(ecc->base + PARM_OFFSET(slot), param, PARM_SIZE); } /** * edma_read_slot - read parameter RAM data from slot * @ecc: pointer to edma_cc struct * @slot: number of parameter RAM slot being copied * @param: where to store copy of parameter RAM data * * Use this to read data from a parameter RAM slot, perhaps to * save them as a template for later reuse. */ static void edma_read_slot(struct edma_cc *ecc, unsigned slot, struct edmacc_param *param) { slot = EDMA_CHAN_SLOT(slot); if (slot >= ecc->num_slots) return; memcpy_fromio(param, ecc->base + PARM_OFFSET(slot), PARM_SIZE); } /** * edma_alloc_slot - allocate DMA parameter RAM * @ecc: pointer to edma_cc struct * @slot: specific slot to allocate; negative for "any unused slot" * * This allocates a parameter RAM slot, initializing it to hold a * dummy transfer. Slots allocated using this routine have not been * mapped to a hardware DMA channel, and will normally be used by * linking to them from a slot associated with a DMA channel. * * Normal use is to pass EDMA_SLOT_ANY as the @slot, but specific * slots may be allocated on behalf of DSP firmware. * * Returns the number of the slot, else negative errno. */ static int edma_alloc_slot(struct edma_cc *ecc, int slot) { if (slot > 0) slot = EDMA_CHAN_SLOT(slot); if (slot < 0) { slot = ecc->num_channels; for (;;) { slot = find_next_zero_bit(ecc->edma_inuse, ecc->num_slots, slot); if (slot == ecc->num_slots) return -ENOMEM; if (!test_and_set_bit(slot, ecc->edma_inuse)) break; } } else if (slot < ecc->num_channels || slot >= ecc->num_slots) { return -EINVAL; } else if (test_and_set_bit(slot, ecc->edma_inuse)) { return -EBUSY; } edma_write_slot(ecc, slot, &dummy_paramset); return EDMA_CTLR_CHAN(ecc->id, slot); } /** * edma_free_slot - deallocate DMA parameter RAM * @ecc: pointer to edma_cc struct * @slot: parameter RAM slot returned from edma_alloc_slot() * * This deallocates the parameter RAM slot allocated by edma_alloc_slot(). * Callers are responsible for ensuring the slot is inactive, and will * not be activated. */ static void edma_free_slot(struct edma_cc *ecc, unsigned slot) { slot = EDMA_CHAN_SLOT(slot); if (slot < ecc->num_channels || slot >= ecc->num_slots) return; edma_write_slot(ecc, slot, &dummy_paramset); clear_bit(slot, ecc->edma_inuse); } /** * edma_link - link one parameter RAM slot to another * @ecc: pointer to edma_cc struct * @from: parameter RAM slot originating the link * @to: parameter RAM slot which is the link target * * The originating slot should not be part of any active DMA transfer. */ static void edma_link(struct edma_cc *ecc, unsigned from, unsigned to) { if (unlikely(EDMA_CTLR(from) != EDMA_CTLR(to))) dev_warn(ecc->dev, "Ignoring eDMA instance for linking\n"); from = EDMA_CHAN_SLOT(from); to = EDMA_CHAN_SLOT(to); if (from >= ecc->num_slots || to >= ecc->num_slots) return; edma_parm_modify(ecc, PARM_LINK_BCNTRLD, from, 0xffff0000, PARM_OFFSET(to)); } /** * edma_get_position - returns the current transfer point * @ecc: pointer to edma_cc struct * @slot: parameter RAM slot being examined * @dst: true selects the dest position, false the source * * Returns the position of the current active slot */ static dma_addr_t edma_get_position(struct edma_cc *ecc, unsigned slot, bool dst) { u32 offs; slot = EDMA_CHAN_SLOT(slot); offs = PARM_OFFSET(slot); offs += dst ? PARM_DST : PARM_SRC; return edma_read(ecc, offs); } /*-----------------------------------------------------------------------*/ /** * edma_start - start dma on a channel * @ecc: pointer to edma_cc struct * @channel: channel being activated * * Channels with event associations will be triggered by their hardware * events, and channels without such associations will be triggered by * software. (At this writing there is no interface for using software * triggers except with channels that don't support hardware triggers.) * * Returns zero on success, else negative errno. */ static int edma_start(struct edma_cc *ecc, unsigned channel) { if (ecc->id != EDMA_CTLR(channel)) { dev_err(ecc->dev, "%s: ID mismatch for eDMA%d: %d\n", __func__, ecc->id, EDMA_CTLR(channel)); return -EINVAL; } channel = EDMA_CHAN_SLOT(channel); if (channel < ecc->num_channels) { int j = channel >> 5; unsigned int mask = BIT(channel & 0x1f); /* EDMA channels without event association */ if (test_bit(channel, ecc->edma_unused)) { dev_dbg(ecc->dev, "ESR%d %08x\n", j, edma_shadow0_read_array(ecc, SH_ESR, j)); edma_shadow0_write_array(ecc, SH_ESR, j, mask); return 0; } /* EDMA channel with event association */ dev_dbg(ecc->dev, "ER%d %08x\n", j, edma_shadow0_read_array(ecc, SH_ER, j)); /* Clear any pending event or error */ edma_write_array(ecc, EDMA_ECR, j, mask); edma_write_array(ecc, EDMA_EMCR, j, mask); /* Clear any SER */ edma_shadow0_write_array(ecc, SH_SECR, j, mask); edma_shadow0_write_array(ecc, SH_EESR, j, mask); dev_dbg(ecc->dev, "EER%d %08x\n", j, edma_shadow0_read_array(ecc, SH_EER, j)); return 0; } return -EINVAL; } /** * edma_stop - stops dma on the channel passed * @ecc: pointer to edma_cc struct * @channel: channel being deactivated * * When @lch is a channel, any active transfer is paused and * all pending hardware events are cleared. The current transfer * may not be resumed, and the channel's Parameter RAM should be * reinitialized before being reused. */ static void edma_stop(struct edma_cc *ecc, unsigned channel) { if (ecc->id != EDMA_CTLR(channel)) { dev_err(ecc->dev, "%s: ID mismatch for eDMA%d: %d\n", __func__, ecc->id, EDMA_CTLR(channel)); return; } channel = EDMA_CHAN_SLOT(channel); if (channel < ecc->num_channels) { int j = channel >> 5; unsigned int mask = BIT(channel & 0x1f); edma_shadow0_write_array(ecc, SH_EECR, j, mask); edma_shadow0_write_array(ecc, SH_ECR, j, mask); edma_shadow0_write_array(ecc, SH_SECR, j, mask); edma_write_array(ecc, EDMA_EMCR, j, mask); /* clear possibly pending completion interrupt */ edma_shadow0_write_array(ecc, SH_ICR, j, mask); dev_dbg(ecc->dev, "EER%d %08x\n", j, edma_shadow0_read_array(ecc, SH_EER, j)); /* REVISIT: consider guarding against inappropriate event * chaining by overwriting with dummy_paramset. */ } } /** * edma_pause - pause dma on a channel * @ecc: pointer to edma_cc struct * @channel: on which edma_start() has been called * * This temporarily disables EDMA hardware events on the specified channel, * preventing them from triggering new transfers on its behalf */ static void edma_pause(struct edma_cc *ecc, unsigned channel) { if (ecc->id != EDMA_CTLR(channel)) { dev_err(ecc->dev, "%s: ID mismatch for eDMA%d: %d\n", __func__, ecc->id, EDMA_CTLR(channel)); return; } channel = EDMA_CHAN_SLOT(channel); if (channel < ecc->num_channels) { unsigned int mask = BIT(channel & 0x1f); edma_shadow0_write_array(ecc, SH_EECR, channel >> 5, mask); } } /** * edma_resume - resumes dma on a paused channel * @ecc: pointer to edma_cc struct * @channel: on which edma_pause() has been called * * This re-enables EDMA hardware events on the specified channel. */ static void edma_resume(struct edma_cc *ecc, unsigned channel) { if (ecc->id != EDMA_CTLR(channel)) { dev_err(ecc->dev, "%s: ID mismatch for eDMA%d: %d\n", __func__, ecc->id, EDMA_CTLR(channel)); return; } channel = EDMA_CHAN_SLOT(channel); if (channel < ecc->num_channels) { unsigned int mask = BIT(channel & 0x1f); edma_shadow0_write_array(ecc, SH_EESR, channel >> 5, mask); } } static int edma_trigger_channel(struct edma_cc *ecc, unsigned channel) { unsigned int mask; if (ecc->id != EDMA_CTLR(channel)) { dev_err(ecc->dev, "%s: ID mismatch for eDMA%d: %d\n", __func__, ecc->id, EDMA_CTLR(channel)); return -EINVAL; } channel = EDMA_CHAN_SLOT(channel); mask = BIT(channel & 0x1f); edma_shadow0_write_array(ecc, SH_ESR, (channel >> 5), mask); dev_dbg(ecc->dev, "ESR%d %08x\n", (channel >> 5), edma_shadow0_read_array(ecc, SH_ESR, (channel >> 5))); return 0; } /****************************************************************************** * * It cleans ParamEntry qand bring back EDMA to initial state if media has * been removed before EDMA has finished.It is usedful for removable media. * Arguments: * ch_no - channel no * * Return: zero on success, or corresponding error no on failure * * FIXME this should not be needed ... edma_stop() should suffice. * *****************************************************************************/ static void edma_clean_channel(struct edma_cc *ecc, unsigned channel) { if (ecc->id != EDMA_CTLR(channel)) { dev_err(ecc->dev, "%s: ID mismatch for eDMA%d: %d\n", __func__, ecc->id, EDMA_CTLR(channel)); return; } channel = EDMA_CHAN_SLOT(channel); if (channel < ecc->num_channels) { int j = (channel >> 5); unsigned int mask = BIT(channel & 0x1f); dev_dbg(ecc->dev, "EMR%d %08x\n", j, edma_read_array(ecc, EDMA_EMR, j)); edma_shadow0_write_array(ecc, SH_ECR, j, mask); /* Clear the corresponding EMR bits */ edma_write_array(ecc, EDMA_EMCR, j, mask); /* Clear any SER */ edma_shadow0_write_array(ecc, SH_SECR, j, mask); edma_write(ecc, EDMA_CCERRCLR, BIT(16) | BIT(1) | BIT(0)); } } /** * edma_alloc_channel - allocate DMA channel and paired parameter RAM * @ecc: pointer to edma_cc struct * @channel: specific channel to allocate; negative for "any unmapped channel" * @callback: optional; to be issued on DMA completion or errors * @data: passed to callback * @eventq_no: an EVENTQ_* constant, used to choose which Transfer * Controller (TC) executes requests using this channel. Use * EVENTQ_DEFAULT unless you really need a high priority queue. * * This allocates a DMA channel and its associated parameter RAM slot. * The parameter RAM is initialized to hold a dummy transfer. * * Normal use is to pass a specific channel number as @channel, to make * use of hardware events mapped to that channel. When the channel will * be used only for software triggering or event chaining, channels not * mapped to hardware events (or mapped to unused events) are preferable. * * DMA transfers start from a channel using edma_start(), or by * chaining. When the transfer described in that channel's parameter RAM * slot completes, that slot's data may be reloaded through a link. * * DMA errors are only reported to the @callback associated with the * channel driving that transfer, but transfer completion callbacks can * be sent to another channel under control of the TCC field in * the option word of the transfer's parameter RAM set. Drivers must not * use DMA transfer completion callbacks for channels they did not allocate. * (The same applies to TCC codes used in transfer chaining.) * * Returns the number of the channel, else negative errno. */ static int edma_alloc_channel(struct edma_cc *ecc, int channel, void (*callback)(unsigned channel, u16 ch_status, void *data), void *data, enum dma_event_q eventq_no) { unsigned done = 0; int ret = 0; if (!ecc->unused_chan_list_done) { /* * Scan all the platform devices to find out the EDMA channels * used and clear them in the unused list, making the rest * available for ARM usage. */ ret = bus_for_each_dev(&platform_bus_type, NULL, ecc, prepare_unused_channel_list); if (ret < 0) return ret; ecc->unused_chan_list_done = true; } if (channel >= 0) { if (ecc->id != EDMA_CTLR(channel)) { dev_err(ecc->dev, "%s: ID mismatch for eDMA%d: %d\n", __func__, ecc->id, EDMA_CTLR(channel)); return -EINVAL; } channel = EDMA_CHAN_SLOT(channel); } if (channel < 0) { channel = 0; for (;;) { channel = find_next_bit(ecc->edma_unused, ecc->num_channels, channel); if (channel == ecc->num_channels) break; if (!test_and_set_bit(channel, ecc->edma_inuse)) { done = 1; break; } channel++; } if (!done) return -ENOMEM; } else if (channel >= ecc->num_channels) { return -EINVAL; } else if (test_and_set_bit(channel, ecc->edma_inuse)) { return -EBUSY; } /* ensure access through shadow region 0 */ edma_or_array2(ecc, EDMA_DRAE, 0, channel >> 5, BIT(channel & 0x1f)); /* ensure no events are pending */ edma_stop(ecc, EDMA_CTLR_CHAN(ecc->id, channel)); edma_write_slot(ecc, channel, &dummy_paramset); if (callback) edma_setup_interrupt(ecc, EDMA_CTLR_CHAN(ecc->id, channel), callback, data); edma_map_dmach_to_queue(ecc, channel, eventq_no); return EDMA_CTLR_CHAN(ecc->id, channel); } /** * edma_free_channel - deallocate DMA channel * @ecc: pointer to edma_cc struct * @channel: dma channel returned from edma_alloc_channel() * * This deallocates the DMA channel and associated parameter RAM slot * allocated by edma_alloc_channel(). * * Callers are responsible for ensuring the channel is inactive, and * will not be reactivated by linking, chaining, or software calls to * edma_start(). */ static void edma_free_channel(struct edma_cc *ecc, unsigned channel) { if (ecc->id != EDMA_CTLR(channel)) { dev_err(ecc->dev, "%s: ID mismatch for eDMA%d: %d\n", __func__, ecc->id, EDMA_CTLR(channel)); return; } channel = EDMA_CHAN_SLOT(channel); if (channel >= ecc->num_channels) return; edma_setup_interrupt(ecc, channel, NULL, NULL); /* REVISIT should probably take out of shadow region 0 */ edma_write_slot(ecc, channel, &dummy_paramset); clear_bit(channel, ecc->edma_inuse); } /* * edma_assign_channel_eventq - move given channel to desired eventq * Arguments: * channel - channel number * eventq_no - queue to move the channel * * Can be used to move a channel to a selected event queue. */ static void edma_assign_channel_eventq(struct edma_cc *ecc, unsigned channel, enum dma_event_q eventq_no) { if (ecc->id != EDMA_CTLR(channel)) { dev_err(ecc->dev, "%s: ID mismatch for eDMA%d: %d\n", __func__, ecc->id, EDMA_CTLR(channel)); return; } channel = EDMA_CHAN_SLOT(channel); if (channel >= ecc->num_channels) return; /* default to low priority queue */ if (eventq_no == EVENTQ_DEFAULT) eventq_no = ecc->default_queue; if (eventq_no >= ecc->num_tc) return; edma_map_dmach_to_queue(ecc, channel, eventq_no); } static irqreturn_t dma_irq_handler(int irq, void *data) { struct edma_cc *ecc = data; int ctlr; u32 sh_ier; u32 sh_ipr; u32 bank; ctlr = ecc->id; if (ctlr < 0) return IRQ_NONE; dev_dbg(ecc->dev, "dma_irq_handler\n"); sh_ipr = edma_shadow0_read_array(ecc, SH_IPR, 0); if (!sh_ipr) { sh_ipr = edma_shadow0_read_array(ecc, SH_IPR, 1); if (!sh_ipr) return IRQ_NONE; sh_ier = edma_shadow0_read_array(ecc, SH_IER, 1); bank = 1; } else { sh_ier = edma_shadow0_read_array(ecc, SH_IER, 0); bank = 0; } do { u32 slot; u32 channel; dev_dbg(ecc->dev, "IPR%d %08x\n", bank, sh_ipr); slot = __ffs(sh_ipr); sh_ipr &= ~(BIT(slot)); if (sh_ier & BIT(slot)) { channel = (bank << 5) | slot; /* Clear the corresponding IPR bits */ edma_shadow0_write_array(ecc, SH_ICR, bank, BIT(slot)); if (ecc->intr_data[channel].callback) ecc->intr_data[channel].callback( EDMA_CTLR_CHAN(ctlr, channel), EDMA_DMA_COMPLETE, ecc->intr_data[channel].data); } } while (sh_ipr); edma_shadow0_write(ecc, SH_IEVAL, 1); return IRQ_HANDLED; } /****************************************************************************** * * DMA error interrupt handler * *****************************************************************************/ static irqreturn_t dma_ccerr_handler(int irq, void *data) { struct edma_cc *ecc = data; int i; int ctlr; unsigned int cnt = 0; ctlr = ecc->id; if (ctlr < 0) return IRQ_NONE; dev_dbg(ecc->dev, "dma_ccerr_handler\n"); if ((edma_read_array(ecc, EDMA_EMR, 0) == 0) && (edma_read_array(ecc, EDMA_EMR, 1) == 0) && (edma_read(ecc, EDMA_QEMR) == 0) && (edma_read(ecc, EDMA_CCERR) == 0)) return IRQ_NONE; while (1) { int j = -1; if (edma_read_array(ecc, EDMA_EMR, 0)) j = 0; else if (edma_read_array(ecc, EDMA_EMR, 1)) j = 1; if (j >= 0) { dev_dbg(ecc->dev, "EMR%d %08x\n", j, edma_read_array(ecc, EDMA_EMR, j)); for (i = 0; i < 32; i++) { int k = (j << 5) + i; if (edma_read_array(ecc, EDMA_EMR, j) & BIT(i)) { /* Clear the corresponding EMR bits */ edma_write_array(ecc, EDMA_EMCR, j, BIT(i)); /* Clear any SER */ edma_shadow0_write_array(ecc, SH_SECR, j, BIT(i)); if (ecc->intr_data[k].callback) { ecc->intr_data[k].callback( EDMA_CTLR_CHAN(ctlr, k), EDMA_DMA_CC_ERROR, ecc->intr_data[k].data); } } } } else if (edma_read(ecc, EDMA_QEMR)) { dev_dbg(ecc->dev, "QEMR %02x\n", edma_read(ecc, EDMA_QEMR)); for (i = 0; i < 8; i++) { if (edma_read(ecc, EDMA_QEMR) & BIT(i)) { /* Clear the corresponding IPR bits */ edma_write(ecc, EDMA_QEMCR, BIT(i)); edma_shadow0_write(ecc, SH_QSECR, BIT(i)); /* NOTE: not reported!! */ } } } else if (edma_read(ecc, EDMA_CCERR)) { dev_dbg(ecc->dev, "CCERR %08x\n", edma_read(ecc, EDMA_CCERR)); /* FIXME: CCERR.BIT(16) ignored! much better * to just write CCERRCLR with CCERR value... */ for (i = 0; i < 8; i++) { if (edma_read(ecc, EDMA_CCERR) & BIT(i)) { /* Clear the corresponding IPR bits */ edma_write(ecc, EDMA_CCERRCLR, BIT(i)); /* NOTE: not reported!! */ } } } if ((edma_read_array(ecc, EDMA_EMR, 0) == 0) && (edma_read_array(ecc, EDMA_EMR, 1) == 0) && (edma_read(ecc, EDMA_QEMR) == 0) && (edma_read(ecc, EDMA_CCERR) == 0)) break; cnt++; if (cnt > 10) break; } edma_write(ecc, EDMA_EEVAL, 1); return IRQ_HANDLED; } static inline struct edma_cc *to_edma_cc(struct dma_device *d) { return container_of(d, struct edma_cc, dma_slave); } static inline struct edma_chan *to_edma_chan(struct dma_chan *c) { return container_of(c, struct edma_chan, vchan.chan); } static inline struct edma_desc *to_edma_desc(struct dma_async_tx_descriptor *tx) { return container_of(tx, struct edma_desc, vdesc.tx); } static void edma_desc_free(struct virt_dma_desc *vdesc) { kfree(container_of(vdesc, struct edma_desc, vdesc)); } /* Dispatch a queued descriptor to the controller (caller holds lock) */ static void edma_execute(struct edma_chan *echan) { struct edma_cc *ecc = echan->ecc; struct virt_dma_desc *vdesc; struct edma_desc *edesc; struct device *dev = echan->vchan.chan.device->dev; int i, j, left, nslots; if (!echan->edesc) { /* Setup is needed for the first transfer */ vdesc = vchan_next_desc(&echan->vchan); if (!vdesc) return; list_del(&vdesc->node); echan->edesc = to_edma_desc(&vdesc->tx); } edesc = echan->edesc; /* Find out how many left */ left = edesc->pset_nr - edesc->processed; nslots = min(MAX_NR_SG, left); edesc->sg_len = 0; /* Write descriptor PaRAM set(s) */ for (i = 0; i < nslots; i++) { j = i + edesc->processed; edma_write_slot(ecc, echan->slot[i], &edesc->pset[j].param); edesc->sg_len += edesc->pset[j].len; dev_vdbg(dev, "\n pset[%d]:\n" " chnum\t%d\n" " slot\t%d\n" " opt\t%08x\n" " src\t%08x\n" " dst\t%08x\n" " abcnt\t%08x\n" " ccnt\t%08x\n" " bidx\t%08x\n" " cidx\t%08x\n" " lkrld\t%08x\n", j, echan->ch_num, echan->slot[i], edesc->pset[j].param.opt, edesc->pset[j].param.src, edesc->pset[j].param.dst, edesc->pset[j].param.a_b_cnt, edesc->pset[j].param.ccnt, edesc->pset[j].param.src_dst_bidx, edesc->pset[j].param.src_dst_cidx, edesc->pset[j].param.link_bcntrld); /* Link to the previous slot if not the last set */ if (i != (nslots - 1)) edma_link(ecc, echan->slot[i], echan->slot[i + 1]); } edesc->processed += nslots; /* * If this is either the last set in a set of SG-list transactions * then setup a link to the dummy slot, this results in all future * events being absorbed and that's OK because we're done */ if (edesc->processed == edesc->pset_nr) { if (edesc->cyclic) edma_link(ecc, echan->slot[nslots - 1], echan->slot[1]); else edma_link(ecc, echan->slot[nslots - 1], echan->ecc->dummy_slot); } if (echan->missed) { /* * This happens due to setup times between intermediate * transfers in long SG lists which have to be broken up into * transfers of MAX_NR_SG */ dev_dbg(dev, "missed event on channel %d\n", echan->ch_num); edma_clean_channel(ecc, echan->ch_num); edma_stop(ecc, echan->ch_num); edma_start(ecc, echan->ch_num); edma_trigger_channel(ecc, echan->ch_num); echan->missed = 0; } else if (edesc->processed <= MAX_NR_SG) { dev_dbg(dev, "first transfer starting on channel %d\n", echan->ch_num); edma_start(ecc, echan->ch_num); } else { dev_dbg(dev, "chan: %d: completed %d elements, resuming\n", echan->ch_num, edesc->processed); edma_resume(ecc, echan->ch_num); } } static int edma_terminate_all(struct dma_chan *chan) { struct edma_chan *echan = to_edma_chan(chan); unsigned long flags; LIST_HEAD(head); spin_lock_irqsave(&echan->vchan.lock, flags); /* * Stop DMA activity: we assume the callback will not be called * after edma_dma() returns (even if it does, it will see * echan->edesc is NULL and exit.) */ if (echan->edesc) { edma_stop(echan->ecc, echan->ch_num); /* Move the cyclic channel back to default queue */ if (echan->edesc->cyclic) edma_assign_channel_eventq(echan->ecc, echan->ch_num, EVENTQ_DEFAULT); /* * free the running request descriptor * since it is not in any of the vdesc lists */ edma_desc_free(&echan->edesc->vdesc); echan->edesc = NULL; } vchan_get_all_descriptors(&echan->vchan, &head); spin_unlock_irqrestore(&echan->vchan.lock, flags); vchan_dma_desc_free_list(&echan->vchan, &head); return 0; } static int edma_slave_config(struct dma_chan *chan, struct dma_slave_config *cfg) { struct edma_chan *echan = to_edma_chan(chan); if (cfg->src_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES || cfg->dst_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES) return -EINVAL; memcpy(&echan->cfg, cfg, sizeof(echan->cfg)); return 0; } static int edma_dma_pause(struct dma_chan *chan) { struct edma_chan *echan = to_edma_chan(chan); if (!echan->edesc) return -EINVAL; edma_pause(echan->ecc, echan->ch_num); return 0; } static int edma_dma_resume(struct dma_chan *chan) { struct edma_chan *echan = to_edma_chan(chan); edma_resume(echan->ecc, echan->ch_num); return 0; } /* * A PaRAM set configuration abstraction used by other modes * @chan: Channel who's PaRAM set we're configuring * @pset: PaRAM set to initialize and setup. * @src_addr: Source address of the DMA * @dst_addr: Destination address of the DMA * @burst: In units of dev_width, how much to send * @dev_width: How much is the dev_width * @dma_length: Total length of the DMA transfer * @direction: Direction of the transfer */ static int edma_config_pset(struct dma_chan *chan, struct edma_pset *epset, dma_addr_t src_addr, dma_addr_t dst_addr, u32 burst, enum dma_slave_buswidth dev_width, unsigned int dma_length, enum dma_transfer_direction direction) { struct edma_chan *echan = to_edma_chan(chan); struct device *dev = chan->device->dev; struct edmacc_param *param = &epset->param; int acnt, bcnt, ccnt, cidx; int src_bidx, dst_bidx, src_cidx, dst_cidx; int absync; acnt = dev_width; /* src/dst_maxburst == 0 is the same case as src/dst_maxburst == 1 */ if (!burst) burst = 1; /* * If the maxburst is equal to the fifo width, use * A-synced transfers. This allows for large contiguous * buffer transfers using only one PaRAM set. */ if (burst == 1) { /* * For the A-sync case, bcnt and ccnt are the remainder * and quotient respectively of the division of: * (dma_length / acnt) by (SZ_64K -1). This is so * that in case bcnt over flows, we have ccnt to use. * Note: In A-sync tranfer only, bcntrld is used, but it * only applies for sg_dma_len(sg) >= SZ_64K. * In this case, the best way adopted is- bccnt for the * first frame will be the remainder below. Then for * every successive frame, bcnt will be SZ_64K-1. This * is assured as bcntrld = 0xffff in end of function. */ absync = false; ccnt = dma_length / acnt / (SZ_64K - 1); bcnt = dma_length / acnt - ccnt * (SZ_64K - 1); /* * If bcnt is non-zero, we have a remainder and hence an * extra frame to transfer, so increment ccnt. */ if (bcnt) ccnt++; else bcnt = SZ_64K - 1; cidx = acnt; } else { /* * If maxburst is greater than the fifo address_width, * use AB-synced transfers where A count is the fifo * address_width and B count is the maxburst. In this * case, we are limited to transfers of C count frames * of (address_width * maxburst) where C count is limited * to SZ_64K-1. This places an upper bound on the length * of an SG segment that can be handled. */ absync = true; bcnt = burst; ccnt = dma_length / (acnt * bcnt); if (ccnt > (SZ_64K - 1)) { dev_err(dev, "Exceeded max SG segment size\n"); return -EINVAL; } cidx = acnt * bcnt; } epset->len = dma_length; if (direction == DMA_MEM_TO_DEV) { src_bidx = acnt; src_cidx = cidx; dst_bidx = 0; dst_cidx = 0; epset->addr = src_addr; } else if (direction == DMA_DEV_TO_MEM) { src_bidx = 0; src_cidx = 0; dst_bidx = acnt; dst_cidx = cidx; epset->addr = dst_addr; } else if (direction == DMA_MEM_TO_MEM) { src_bidx = acnt; src_cidx = cidx; dst_bidx = acnt; dst_cidx = cidx; } else { dev_err(dev, "%s: direction not implemented yet\n", __func__); return -EINVAL; } param->opt = EDMA_TCC(EDMA_CHAN_SLOT(echan->ch_num)); /* Configure A or AB synchronized transfers */ if (absync) param->opt |= SYNCDIM; param->src = src_addr; param->dst = dst_addr; param->src_dst_bidx = (dst_bidx << 16) | src_bidx; param->src_dst_cidx = (dst_cidx << 16) | src_cidx; param->a_b_cnt = bcnt << 16 | acnt; param->ccnt = ccnt; /* * Only time when (bcntrld) auto reload is required is for * A-sync case, and in this case, a requirement of reload value * of SZ_64K-1 only is assured. 'link' is initially set to NULL * and then later will be populated by edma_execute. */ param->link_bcntrld = 0xffffffff; return absync; } static struct dma_async_tx_descriptor *edma_prep_slave_sg( struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len, enum dma_transfer_direction direction, unsigned long tx_flags, void *context) { struct edma_chan *echan = to_edma_chan(chan); struct device *dev = chan->device->dev; struct edma_desc *edesc; dma_addr_t src_addr = 0, dst_addr = 0; enum dma_slave_buswidth dev_width; u32 burst; struct scatterlist *sg; int i, nslots, ret; if (unlikely(!echan || !sgl || !sg_len)) return NULL; if (direction == DMA_DEV_TO_MEM) { src_addr = echan->cfg.src_addr; dev_width = echan->cfg.src_addr_width; burst = echan->cfg.src_maxburst; } else if (direction == DMA_MEM_TO_DEV) { dst_addr = echan->cfg.dst_addr; dev_width = echan->cfg.dst_addr_width; burst = echan->cfg.dst_maxburst; } else { dev_err(dev, "%s: bad direction: %d\n", __func__, direction); return NULL; } if (dev_width == DMA_SLAVE_BUSWIDTH_UNDEFINED) { dev_err(dev, "%s: Undefined slave buswidth\n", __func__); return NULL; } edesc = kzalloc(sizeof(*edesc) + sg_len * sizeof(edesc->pset[0]), GFP_ATOMIC); if (!edesc) { dev_err(dev, "%s: Failed to allocate a descriptor\n", __func__); return NULL; } edesc->pset_nr = sg_len; edesc->residue = 0; edesc->direction = direction; edesc->echan = echan; /* Allocate a PaRAM slot, if needed */ nslots = min_t(unsigned, MAX_NR_SG, sg_len); for (i = 0; i < nslots; i++) { if (echan->slot[i] < 0) { echan->slot[i] = edma_alloc_slot(echan->ecc, EDMA_SLOT_ANY); if (echan->slot[i] < 0) { kfree(edesc); dev_err(dev, "%s: Failed to allocate slot\n", __func__); return NULL; } } } /* Configure PaRAM sets for each SG */ for_each_sg(sgl, sg, sg_len, i) { /* Get address for each SG */ if (direction == DMA_DEV_TO_MEM) dst_addr = sg_dma_address(sg); else src_addr = sg_dma_address(sg); ret = edma_config_pset(chan, &edesc->pset[i], src_addr, dst_addr, burst, dev_width, sg_dma_len(sg), direction); if (ret < 0) { kfree(edesc); return NULL; } edesc->absync = ret; edesc->residue += sg_dma_len(sg); /* If this is the last in a current SG set of transactions, enable interrupts so that next set is processed */ if (!((i+1) % MAX_NR_SG)) edesc->pset[i].param.opt |= TCINTEN; /* If this is the last set, enable completion interrupt flag */ if (i == sg_len - 1) edesc->pset[i].param.opt |= TCINTEN; } edesc->residue_stat = edesc->residue; return vchan_tx_prep(&echan->vchan, &edesc->vdesc, tx_flags); } static struct dma_async_tx_descriptor *edma_prep_dma_memcpy( struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, size_t len, unsigned long tx_flags) { int ret; struct edma_desc *edesc; struct device *dev = chan->device->dev; struct edma_chan *echan = to_edma_chan(chan); if (unlikely(!echan || !len)) return NULL; edesc = kzalloc(sizeof(*edesc) + sizeof(edesc->pset[0]), GFP_ATOMIC); if (!edesc) { dev_dbg(dev, "Failed to allocate a descriptor\n"); return NULL; } edesc->pset_nr = 1; ret = edma_config_pset(chan, &edesc->pset[0], src, dest, 1, DMA_SLAVE_BUSWIDTH_4_BYTES, len, DMA_MEM_TO_MEM); if (ret < 0) return NULL; edesc->absync = ret; /* * Enable intermediate transfer chaining to re-trigger channel * on completion of every TR, and enable transfer-completion * interrupt on completion of the whole transfer. */ edesc->pset[0].param.opt |= ITCCHEN; edesc->pset[0].param.opt |= TCINTEN; return vchan_tx_prep(&echan->vchan, &edesc->vdesc, tx_flags); } static struct dma_async_tx_descriptor *edma_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 tx_flags) { struct edma_chan *echan = to_edma_chan(chan); struct device *dev = chan->device->dev; struct edma_desc *edesc; dma_addr_t src_addr, dst_addr; enum dma_slave_buswidth dev_width; u32 burst; int i, ret, nslots; if (unlikely(!echan || !buf_len || !period_len)) return NULL; if (direction == DMA_DEV_TO_MEM) { src_addr = echan->cfg.src_addr; dst_addr = buf_addr; dev_width = echan->cfg.src_addr_width; burst = echan->cfg.src_maxburst; } else if (direction == DMA_MEM_TO_DEV) { src_addr = buf_addr; dst_addr = echan->cfg.dst_addr; dev_width = echan->cfg.dst_addr_width; burst = echan->cfg.dst_maxburst; } else { dev_err(dev, "%s: bad direction: %d\n", __func__, direction); return NULL; } if (dev_width == DMA_SLAVE_BUSWIDTH_UNDEFINED) { dev_err(dev, "%s: Undefined slave buswidth\n", __func__); return NULL; } if (unlikely(buf_len % period_len)) { dev_err(dev, "Period should be multiple of Buffer length\n"); return NULL; } nslots = (buf_len / period_len) + 1; /* * Cyclic DMA users such as audio cannot tolerate delays introduced * by cases where the number of periods is more than the maximum * number of SGs the EDMA driver can handle at a time. For DMA types * such as Slave SGs, such delays are tolerable and synchronized, * but the synchronization is difficult to achieve with Cyclic and * cannot be guaranteed, so we error out early. */ if (nslots > MAX_NR_SG) return NULL; edesc = kzalloc(sizeof(*edesc) + nslots * sizeof(edesc->pset[0]), GFP_ATOMIC); if (!edesc) { dev_err(dev, "%s: Failed to allocate a descriptor\n", __func__); return NULL; } edesc->cyclic = 1; edesc->pset_nr = nslots; edesc->residue = edesc->residue_stat = buf_len; edesc->direction = direction; edesc->echan = echan; dev_dbg(dev, "%s: channel=%d nslots=%d period_len=%zu buf_len=%zu\n", __func__, echan->ch_num, nslots, period_len, buf_len); for (i = 0; i < nslots; i++) { /* Allocate a PaRAM slot, if needed */ if (echan->slot[i] < 0) { echan->slot[i] = edma_alloc_slot(echan->ecc, EDMA_SLOT_ANY); if (echan->slot[i] < 0) { kfree(edesc); dev_err(dev, "%s: Failed to allocate slot\n", __func__); return NULL; } } if (i == nslots - 1) { memcpy(&edesc->pset[i], &edesc->pset[0], sizeof(edesc->pset[0])); break; } ret = edma_config_pset(chan, &edesc->pset[i], src_addr, dst_addr, burst, dev_width, period_len, direction); if (ret < 0) { kfree(edesc); return NULL; } if (direction == DMA_DEV_TO_MEM) dst_addr += period_len; else src_addr += period_len; dev_vdbg(dev, "%s: Configure period %d of buf:\n", __func__, i); dev_vdbg(dev, "\n pset[%d]:\n" " chnum\t%d\n" " slot\t%d\n" " opt\t%08x\n" " src\t%08x\n" " dst\t%08x\n" " abcnt\t%08x\n" " ccnt\t%08x\n" " bidx\t%08x\n" " cidx\t%08x\n" " lkrld\t%08x\n", i, echan->ch_num, echan->slot[i], edesc->pset[i].param.opt, edesc->pset[i].param.src, edesc->pset[i].param.dst, edesc->pset[i].param.a_b_cnt, edesc->pset[i].param.ccnt, edesc->pset[i].param.src_dst_bidx, edesc->pset[i].param.src_dst_cidx, edesc->pset[i].param.link_bcntrld); edesc->absync = ret; /* * Enable period interrupt only if it is requested */ if (tx_flags & DMA_PREP_INTERRUPT) edesc->pset[i].param.opt |= TCINTEN; } /* Place the cyclic channel to highest priority queue */ edma_assign_channel_eventq(echan->ecc, echan->ch_num, EVENTQ_0); return vchan_tx_prep(&echan->vchan, &edesc->vdesc, tx_flags); } static void edma_callback(unsigned ch_num, u16 ch_status, void *data) { struct edma_chan *echan = data; struct edma_cc *ecc = echan->ecc; struct device *dev = echan->vchan.chan.device->dev; struct edma_desc *edesc; struct edmacc_param p; edesc = echan->edesc; spin_lock(&echan->vchan.lock); switch (ch_status) { case EDMA_DMA_COMPLETE: if (edesc) { if (edesc->cyclic) { vchan_cyclic_callback(&edesc->vdesc); goto out; } else if (edesc->processed == edesc->pset_nr) { dev_dbg(dev, "Transfer completed on channel %d\n", ch_num); edesc->residue = 0; edma_stop(ecc, echan->ch_num); vchan_cookie_complete(&edesc->vdesc); echan->edesc = NULL; } else { dev_dbg(dev, "Sub transfer completed on channel %d\n", ch_num); edma_pause(ecc, echan->ch_num); /* Update statistics for tx_status */ edesc->residue -= edesc->sg_len; edesc->residue_stat = edesc->residue; edesc->processed_stat = edesc->processed; } edma_execute(echan); } break; case EDMA_DMA_CC_ERROR: edma_read_slot(ecc, echan->slot[0], &p); /* * Issue later based on missed flag which will be sure * to happen as: * (1) we finished transmitting an intermediate slot and * edma_execute is coming up. * (2) or we finished current transfer and issue will * call edma_execute. * * Important note: issuing can be dangerous here and * lead to some nasty recursion when we are in a NULL * slot. So we avoid doing so and set the missed flag. */ if (p.a_b_cnt == 0 && p.ccnt == 0) { dev_dbg(dev, "Error on null slot, setting miss\n"); echan->missed = 1; } else { /* * The slot is already programmed but the event got * missed, so its safe to issue it here. */ dev_dbg(dev, "Missed event, TRIGGERING\n"); edma_clean_channel(ecc, echan->ch_num); edma_stop(ecc, echan->ch_num); edma_start(ecc, echan->ch_num); edma_trigger_channel(ecc, echan->ch_num); } break; default: break; } out: spin_unlock(&echan->vchan.lock); } /* Alloc channel resources */ static int edma_alloc_chan_resources(struct dma_chan *chan) { struct edma_chan *echan = to_edma_chan(chan); struct device *dev = chan->device->dev; int ret; int a_ch_num; LIST_HEAD(descs); a_ch_num = edma_alloc_channel(echan->ecc, echan->ch_num, edma_callback, echan, EVENTQ_DEFAULT); if (a_ch_num < 0) { ret = -ENODEV; goto err_no_chan; } if (a_ch_num != echan->ch_num) { dev_err(dev, "failed to allocate requested channel %u:%u\n", EDMA_CTLR(echan->ch_num), EDMA_CHAN_SLOT(echan->ch_num)); ret = -ENODEV; goto err_wrong_chan; } echan->alloced = true; echan->slot[0] = echan->ch_num; dev_dbg(dev, "allocated channel %d for %u:%u\n", echan->ch_num, EDMA_CTLR(echan->ch_num), EDMA_CHAN_SLOT(echan->ch_num)); return 0; err_wrong_chan: edma_free_channel(echan->ecc, a_ch_num); err_no_chan: return ret; } /* Free channel resources */ static void edma_free_chan_resources(struct dma_chan *chan) { struct edma_chan *echan = to_edma_chan(chan); int i; /* Terminate transfers */ edma_stop(echan->ecc, echan->ch_num); vchan_free_chan_resources(&echan->vchan); /* Free EDMA PaRAM slots */ for (i = 1; i < EDMA_MAX_SLOTS; i++) { if (echan->slot[i] >= 0) { edma_free_slot(echan->ecc, echan->slot[i]); echan->slot[i] = -1; } } /* Free EDMA channel */ if (echan->alloced) { edma_free_channel(echan->ecc, echan->ch_num); echan->alloced = false; } dev_dbg(chan->device->dev, "freeing channel for %u\n", echan->ch_num); } /* Send pending descriptor to hardware */ static void edma_issue_pending(struct dma_chan *chan) { struct edma_chan *echan = to_edma_chan(chan); unsigned long flags; spin_lock_irqsave(&echan->vchan.lock, flags); if (vchan_issue_pending(&echan->vchan) && !echan->edesc) edma_execute(echan); spin_unlock_irqrestore(&echan->vchan.lock, flags); } static u32 edma_residue(struct edma_desc *edesc) { bool dst = edesc->direction == DMA_DEV_TO_MEM; struct edma_pset *pset = edesc->pset; dma_addr_t done, pos; int i; /* * We always read the dst/src position from the first RamPar * pset. That's the one which is active now. */ pos = edma_get_position(edesc->echan->ecc, edesc->echan->slot[0], dst); /* * Cyclic is simple. Just subtract pset[0].addr from pos. * * We never update edesc->residue in the cyclic case, so we * can tell the remaining room to the end of the circular * buffer. */ if (edesc->cyclic) { done = pos - pset->addr; edesc->residue_stat = edesc->residue - done; return edesc->residue_stat; } /* * For SG operation we catch up with the last processed * status. */ pset += edesc->processed_stat; for (i = edesc->processed_stat; i < edesc->processed; i++, pset++) { /* * If we are inside this pset address range, we know * this is the active one. Get the current delta and * stop walking the psets. */ if (pos >= pset->addr && pos < pset->addr + pset->len) return edesc->residue_stat - (pos - pset->addr); /* Otherwise mark it done and update residue_stat. */ edesc->processed_stat++; edesc->residue_stat -= pset->len; } return edesc->residue_stat; } /* Check request completion status */ static enum dma_status edma_tx_status(struct dma_chan *chan, dma_cookie_t cookie, struct dma_tx_state *txstate) { struct edma_chan *echan = to_edma_chan(chan); struct virt_dma_desc *vdesc; enum dma_status ret; unsigned long flags; ret = dma_cookie_status(chan, cookie, txstate); if (ret == DMA_COMPLETE || !txstate) return ret; spin_lock_irqsave(&echan->vchan.lock, flags); if (echan->edesc && echan->edesc->vdesc.tx.cookie == cookie) txstate->residue = edma_residue(echan->edesc); else if ((vdesc = vchan_find_desc(&echan->vchan, cookie))) txstate->residue = to_edma_desc(&vdesc->tx)->residue; spin_unlock_irqrestore(&echan->vchan.lock, flags); return ret; } static void __init edma_chan_init(struct edma_cc *ecc, struct dma_device *dma, struct edma_chan *echans) { int i, j; for (i = 0; i < ecc->num_channels; i++) { struct edma_chan *echan = &echans[i]; echan->ch_num = EDMA_CTLR_CHAN(ecc->id, i); echan->ecc = ecc; echan->vchan.desc_free = edma_desc_free; vchan_init(&echan->vchan, dma); INIT_LIST_HEAD(&echan->node); for (j = 0; j < EDMA_MAX_SLOTS; j++) echan->slot[j] = -1; } } #define EDMA_DMA_BUSWIDTHS (BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \ BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \ BIT(DMA_SLAVE_BUSWIDTH_3_BYTES) | \ BIT(DMA_SLAVE_BUSWIDTH_4_BYTES)) static void edma_dma_init(struct edma_cc *ecc, struct dma_device *dma, struct device *dev) { dma->device_prep_slave_sg = edma_prep_slave_sg; dma->device_prep_dma_cyclic = edma_prep_dma_cyclic; dma->device_prep_dma_memcpy = edma_prep_dma_memcpy; dma->device_alloc_chan_resources = edma_alloc_chan_resources; dma->device_free_chan_resources = edma_free_chan_resources; dma->device_issue_pending = edma_issue_pending; dma->device_tx_status = edma_tx_status; dma->device_config = edma_slave_config; dma->device_pause = edma_dma_pause; dma->device_resume = edma_dma_resume; dma->device_terminate_all = edma_terminate_all; dma->src_addr_widths = EDMA_DMA_BUSWIDTHS; dma->dst_addr_widths = EDMA_DMA_BUSWIDTHS; dma->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); dma->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST; dma->dev = dev; /* * code using dma memcpy must make sure alignment of * length is at dma->copy_align boundary. */ dma->copy_align = DMAENGINE_ALIGN_4_BYTES; INIT_LIST_HEAD(&dma->channels); } static int edma_setup_from_hw(struct device *dev, struct edma_soc_info *pdata, struct edma_cc *ecc) { int i; u32 value, cccfg; s8 (*queue_priority_map)[2]; /* Decode the eDMA3 configuration from CCCFG register */ cccfg = edma_read(ecc, EDMA_CCCFG); value = GET_NUM_REGN(cccfg); ecc->num_region = BIT(value); value = GET_NUM_DMACH(cccfg); ecc->num_channels = BIT(value + 1); value = GET_NUM_PAENTRY(cccfg); ecc->num_slots = BIT(value + 4); value = GET_NUM_EVQUE(cccfg); ecc->num_tc = value + 1; dev_dbg(dev, "eDMA3 CC HW configuration (cccfg: 0x%08x):\n", cccfg); dev_dbg(dev, "num_region: %u\n", ecc->num_region); dev_dbg(dev, "num_channels: %u\n", ecc->num_channels); dev_dbg(dev, "num_slots: %u\n", ecc->num_slots); dev_dbg(dev, "num_tc: %u\n", ecc->num_tc); /* Nothing need to be done if queue priority is provided */ if (pdata->queue_priority_mapping) return 0; /* * Configure TC/queue priority as follows: * Q0 - priority 0 * Q1 - priority 1 * Q2 - priority 2 * ... * The meaning of priority numbers: 0 highest priority, 7 lowest * priority. So Q0 is the highest priority queue and the last queue has * the lowest priority. */ queue_priority_map = devm_kcalloc(dev, ecc->num_tc + 1, sizeof(s8), GFP_KERNEL); if (!queue_priority_map) return -ENOMEM; for (i = 0; i < ecc->num_tc; i++) { queue_priority_map[i][0] = i; queue_priority_map[i][1] = i; } queue_priority_map[i][0] = -1; queue_priority_map[i][1] = -1; pdata->queue_priority_mapping = queue_priority_map; /* Default queue has the lowest priority */ pdata->default_queue = i - 1; return 0; } #if IS_ENABLED(CONFIG_OF) static int edma_xbar_event_map(struct device *dev, struct edma_soc_info *pdata, size_t sz) { const char pname[] = "ti,edma-xbar-event-map"; struct resource res; void __iomem *xbar; s16 (*xbar_chans)[2]; size_t nelm = sz / sizeof(s16); u32 shift, offset, mux; int ret, i; xbar_chans = devm_kcalloc(dev, nelm + 2, sizeof(s16), GFP_KERNEL); if (!xbar_chans) return -ENOMEM; ret = of_address_to_resource(dev->of_node, 1, &res); if (ret) return -ENOMEM; xbar = devm_ioremap(dev, res.start, resource_size(&res)); if (!xbar) return -ENOMEM; ret = of_property_read_u16_array(dev->of_node, pname, (u16 *)xbar_chans, nelm); if (ret) return -EIO; /* Invalidate last entry for the other user of this mess */ nelm >>= 1; xbar_chans[nelm][0] = -1; xbar_chans[nelm][1] = -1; for (i = 0; i < nelm; i++) { shift = (xbar_chans[i][1] & 0x03) << 3; offset = xbar_chans[i][1] & 0xfffffffc; mux = readl(xbar + offset); mux &= ~(0xff << shift); mux |= xbar_chans[i][0] << shift; writel(mux, (xbar + offset)); } pdata->xbar_chans = (const s16 (*)[2]) xbar_chans; return 0; } static int edma_of_parse_dt(struct device *dev, struct edma_soc_info *pdata) { int ret = 0; struct property *prop; size_t sz; struct edma_rsv_info *rsv_info; rsv_info = devm_kzalloc(dev, sizeof(struct edma_rsv_info), GFP_KERNEL); if (!rsv_info) return -ENOMEM; pdata->rsv = rsv_info; prop = of_find_property(dev->of_node, "ti,edma-xbar-event-map", &sz); if (prop) ret = edma_xbar_event_map(dev, pdata, sz); return ret; } static struct edma_soc_info *edma_setup_info_from_dt(struct device *dev) { struct edma_soc_info *info; int ret; info = devm_kzalloc(dev, sizeof(struct edma_soc_info), GFP_KERNEL); if (!info) return ERR_PTR(-ENOMEM); ret = edma_of_parse_dt(dev, info); if (ret) return ERR_PTR(ret); return info; } #else static struct edma_soc_info *edma_setup_info_from_dt(struct device *dev) { return ERR_PTR(-EINVAL); } #endif static int edma_probe(struct platform_device *pdev) { struct edma_soc_info *info = pdev->dev.platform_data; s8 (*queue_priority_mapping)[2]; int i, off, ln; const s16 (*rsv_chans)[2]; const s16 (*rsv_slots)[2]; const s16 (*xbar_chans)[2]; int irq; char *irq_name; struct resource *mem; struct device_node *node = pdev->dev.of_node; struct device *dev = &pdev->dev; struct edma_cc *ecc; int ret; if (node) { info = edma_setup_info_from_dt(dev); if (IS_ERR(info)) { dev_err(dev, "failed to get DT data\n"); return PTR_ERR(info); } } if (!info) return -ENODEV; pm_runtime_enable(dev); ret = pm_runtime_get_sync(dev); if (ret < 0) { dev_err(dev, "pm_runtime_get_sync() failed\n"); return ret; } ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32)); if (ret) return ret; ecc = devm_kzalloc(dev, sizeof(*ecc), GFP_KERNEL); if (!ecc) { dev_err(dev, "Can't allocate controller\n"); return -ENOMEM; } ecc->dev = dev; ecc->id = pdev->id; /* When booting with DT the pdev->id is -1 */ if (ecc->id < 0) ecc->id = 0; mem = platform_get_resource_byname(pdev, IORESOURCE_MEM, "edma3_cc"); if (!mem) { dev_dbg(dev, "mem resource not found, using index 0\n"); mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!mem) { dev_err(dev, "no mem resource?\n"); return -ENODEV; } } ecc->base = devm_ioremap_resource(dev, mem); if (IS_ERR(ecc->base)) return PTR_ERR(ecc->base); platform_set_drvdata(pdev, ecc); /* Get eDMA3 configuration from IP */ ret = edma_setup_from_hw(dev, info, ecc); if (ret) return ret; /* Allocate memory based on the information we got from the IP */ ecc->slave_chans = devm_kcalloc(dev, ecc->num_channels, sizeof(*ecc->slave_chans), GFP_KERNEL); if (!ecc->slave_chans) return -ENOMEM; ecc->intr_data = devm_kcalloc(dev, ecc->num_channels, sizeof(*ecc->intr_data), GFP_KERNEL); if (!ecc->intr_data) return -ENOMEM; ecc->edma_unused = devm_kcalloc(dev, BITS_TO_LONGS(ecc->num_channels), sizeof(unsigned long), GFP_KERNEL); if (!ecc->edma_unused) return -ENOMEM; ecc->edma_inuse = devm_kcalloc(dev, BITS_TO_LONGS(ecc->num_slots), sizeof(unsigned long), GFP_KERNEL); if (!ecc->edma_inuse) return -ENOMEM; ecc->default_queue = info->default_queue; for (i = 0; i < ecc->num_slots; i++) edma_write_slot(ecc, i, &dummy_paramset); /* Mark all channels as unused */ memset(ecc->edma_unused, 0xff, sizeof(ecc->edma_unused)); if (info->rsv) { /* Clear the reserved channels in unused list */ rsv_chans = info->rsv->rsv_chans; if (rsv_chans) { for (i = 0; rsv_chans[i][0] != -1; i++) { off = rsv_chans[i][0]; ln = rsv_chans[i][1]; clear_bits(off, ln, ecc->edma_unused); } } /* Set the reserved slots in inuse list */ rsv_slots = info->rsv->rsv_slots; if (rsv_slots) { for (i = 0; rsv_slots[i][0] != -1; i++) { off = rsv_slots[i][0]; ln = rsv_slots[i][1]; set_bits(off, ln, ecc->edma_inuse); } } } /* Clear the xbar mapped channels in unused list */ xbar_chans = info->xbar_chans; if (xbar_chans) { for (i = 0; xbar_chans[i][1] != -1; i++) { off = xbar_chans[i][1]; clear_bits(off, 1, ecc->edma_unused); } } irq = platform_get_irq_byname(pdev, "edma3_ccint"); if (irq < 0 && node) irq = irq_of_parse_and_map(node, 0); if (irq >= 0) { irq_name = devm_kasprintf(dev, GFP_KERNEL, "%s_ccint", dev_name(dev)); ret = devm_request_irq(dev, irq, dma_irq_handler, 0, irq_name, ecc); if (ret) { dev_err(dev, "CCINT (%d) failed --> %d\n", irq, ret); return ret; } } irq = platform_get_irq_byname(pdev, "edma3_ccerrint"); if (irq < 0 && node) irq = irq_of_parse_and_map(node, 2); if (irq >= 0) { irq_name = devm_kasprintf(dev, GFP_KERNEL, "%s_ccerrint", dev_name(dev)); ret = devm_request_irq(dev, irq, dma_ccerr_handler, 0, irq_name, ecc); if (ret) { dev_err(dev, "CCERRINT (%d) failed --> %d\n", irq, ret); return ret; } } for (i = 0; i < ecc->num_channels; i++) edma_map_dmach_to_queue(ecc, i, info->default_queue); queue_priority_mapping = info->queue_priority_mapping; /* Event queue priority mapping */ for (i = 0; queue_priority_mapping[i][0] != -1; i++) edma_assign_priority_to_queue(ecc, queue_priority_mapping[i][0], queue_priority_mapping[i][1]); /* Map the channel to param entry if channel mapping logic exist */ if (edma_read(ecc, EDMA_CCCFG) & CHMAP_EXIST) edma_direct_dmach_to_param_mapping(ecc); for (i = 0; i < ecc->num_region; i++) { edma_write_array2(ecc, EDMA_DRAE, i, 0, 0x0); edma_write_array2(ecc, EDMA_DRAE, i, 1, 0x0); edma_write_array(ecc, EDMA_QRAE, i, 0x0); } ecc->info = info; ecc->dummy_slot = edma_alloc_slot(ecc, EDMA_SLOT_ANY); if (ecc->dummy_slot < 0) { dev_err(dev, "Can't allocate PaRAM dummy slot\n"); return ecc->dummy_slot; } dma_cap_zero(ecc->dma_slave.cap_mask); dma_cap_set(DMA_SLAVE, ecc->dma_slave.cap_mask); dma_cap_set(DMA_CYCLIC, ecc->dma_slave.cap_mask); dma_cap_set(DMA_MEMCPY, ecc->dma_slave.cap_mask); edma_dma_init(ecc, &ecc->dma_slave, dev); edma_chan_init(ecc, &ecc->dma_slave, ecc->slave_chans); ret = dma_async_device_register(&ecc->dma_slave); if (ret) goto err_reg1; if (node) of_dma_controller_register(node, of_dma_xlate_by_chan_id, &ecc->dma_slave); dev_info(dev, "TI EDMA DMA engine driver\n"); return 0; err_reg1: edma_free_slot(ecc, ecc->dummy_slot); return ret; } static int edma_remove(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct edma_cc *ecc = dev_get_drvdata(dev); if (dev->of_node) of_dma_controller_free(dev->of_node); dma_async_device_unregister(&ecc->dma_slave); edma_free_slot(ecc, ecc->dummy_slot); return 0; } #ifdef CONFIG_PM_SLEEP static int edma_pm_resume(struct device *dev) { struct edma_cc *ecc = dev_get_drvdata(dev); int i; s8 (*queue_priority_mapping)[2]; queue_priority_mapping = ecc->info->queue_priority_mapping; /* Event queue priority mapping */ for (i = 0; queue_priority_mapping[i][0] != -1; i++) edma_assign_priority_to_queue(ecc, queue_priority_mapping[i][0], queue_priority_mapping[i][1]); /* Map the channel to param entry if channel mapping logic */ if (edma_read(ecc, EDMA_CCCFG) & CHMAP_EXIST) edma_direct_dmach_to_param_mapping(ecc); for (i = 0; i < ecc->num_channels; i++) { if (test_bit(i, ecc->edma_inuse)) { /* ensure access through shadow region 0 */ edma_or_array2(ecc, EDMA_DRAE, 0, i >> 5, BIT(i & 0x1f)); edma_setup_interrupt(ecc, EDMA_CTLR_CHAN(ecc->id, i), ecc->intr_data[i].callback, ecc->intr_data[i].data); } } return 0; } #endif static const struct dev_pm_ops edma_pm_ops = { SET_LATE_SYSTEM_SLEEP_PM_OPS(NULL, edma_pm_resume) }; static struct platform_driver edma_driver = { .probe = edma_probe, .remove = edma_remove, .driver = { .name = "edma", .pm = &edma_pm_ops, .of_match_table = edma_of_ids, }, }; bool edma_filter_fn(struct dma_chan *chan, void *param) { if (chan->device->dev->driver == &edma_driver.driver) { struct edma_chan *echan = to_edma_chan(chan); unsigned ch_req = *(unsigned *)param; return ch_req == echan->ch_num; } return false; } EXPORT_SYMBOL(edma_filter_fn); static int edma_init(void) { return platform_driver_register(&edma_driver); } subsys_initcall(edma_init); static void __exit edma_exit(void) { platform_driver_unregister(&edma_driver); } module_exit(edma_exit); MODULE_AUTHOR("Matt Porter "); MODULE_DESCRIPTION("TI EDMA DMA engine driver"); MODULE_LICENSE("GPL v2");