/* * Ingenic JZ4780 DMA controller * * Copyright (c) 2015 Imagination Technologies * Author: Alex Smith <alex@alex-smith.me.uk> * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the * Free Software Foundation; either version 2 of the License, or (at your * option) any later version. */ #include <linux/clk.h> #include <linux/dmapool.h> #include <linux/init.h> #include <linux/interrupt.h> #include <linux/module.h> #include <linux/of.h> #include <linux/of_dma.h> #include <linux/platform_device.h> #include <linux/slab.h> #include "dmaengine.h" #include "virt-dma.h" #define JZ_DMA_NR_CHANNELS 32 /* Global registers. */ #define JZ_DMA_REG_DMAC 0x1000 #define JZ_DMA_REG_DIRQP 0x1004 #define JZ_DMA_REG_DDR 0x1008 #define JZ_DMA_REG_DDRS 0x100c #define JZ_DMA_REG_DMACP 0x101c #define JZ_DMA_REG_DSIRQP 0x1020 #define JZ_DMA_REG_DSIRQM 0x1024 #define JZ_DMA_REG_DCIRQP 0x1028 #define JZ_DMA_REG_DCIRQM 0x102c /* Per-channel registers. */ #define JZ_DMA_REG_CHAN(n) (n * 0x20) #define JZ_DMA_REG_DSA(n) (0x00 + JZ_DMA_REG_CHAN(n)) #define JZ_DMA_REG_DTA(n) (0x04 + JZ_DMA_REG_CHAN(n)) #define JZ_DMA_REG_DTC(n) (0x08 + JZ_DMA_REG_CHAN(n)) #define JZ_DMA_REG_DRT(n) (0x0c + JZ_DMA_REG_CHAN(n)) #define JZ_DMA_REG_DCS(n) (0x10 + JZ_DMA_REG_CHAN(n)) #define JZ_DMA_REG_DCM(n) (0x14 + JZ_DMA_REG_CHAN(n)) #define JZ_DMA_REG_DDA(n) (0x18 + JZ_DMA_REG_CHAN(n)) #define JZ_DMA_REG_DSD(n) (0x1c + JZ_DMA_REG_CHAN(n)) #define JZ_DMA_DMAC_DMAE BIT(0) #define JZ_DMA_DMAC_AR BIT(2) #define JZ_DMA_DMAC_HLT BIT(3) #define JZ_DMA_DMAC_FMSC BIT(31) #define JZ_DMA_DRT_AUTO 0x8 #define JZ_DMA_DCS_CTE BIT(0) #define JZ_DMA_DCS_HLT BIT(2) #define JZ_DMA_DCS_TT BIT(3) #define JZ_DMA_DCS_AR BIT(4) #define JZ_DMA_DCS_DES8 BIT(30) #define JZ_DMA_DCM_LINK BIT(0) #define JZ_DMA_DCM_TIE BIT(1) #define JZ_DMA_DCM_STDE BIT(2) #define JZ_DMA_DCM_TSZ_SHIFT 8 #define JZ_DMA_DCM_TSZ_MASK (0x7 << JZ_DMA_DCM_TSZ_SHIFT) #define JZ_DMA_DCM_DP_SHIFT 12 #define JZ_DMA_DCM_SP_SHIFT 14 #define JZ_DMA_DCM_DAI BIT(22) #define JZ_DMA_DCM_SAI BIT(23) #define JZ_DMA_SIZE_4_BYTE 0x0 #define JZ_DMA_SIZE_1_BYTE 0x1 #define JZ_DMA_SIZE_2_BYTE 0x2 #define JZ_DMA_SIZE_16_BYTE 0x3 #define JZ_DMA_SIZE_32_BYTE 0x4 #define JZ_DMA_SIZE_64_BYTE 0x5 #define JZ_DMA_SIZE_128_BYTE 0x6 #define JZ_DMA_WIDTH_32_BIT 0x0 #define JZ_DMA_WIDTH_8_BIT 0x1 #define JZ_DMA_WIDTH_16_BIT 0x2 #define JZ_DMA_BUSWIDTHS (BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \ BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \ BIT(DMA_SLAVE_BUSWIDTH_4_BYTES)) /** * struct jz4780_dma_hwdesc - descriptor structure read by the DMA controller. * @dcm: value for the DCM (channel command) register * @dsa: source address * @dta: target address * @dtc: transfer count (number of blocks of the transfer size specified in DCM * to transfer) in the low 24 bits, offset of the next descriptor from the * descriptor base address in the upper 8 bits. * @sd: target/source stride difference (in stride transfer mode). * @drt: request type */ struct jz4780_dma_hwdesc { uint32_t dcm; uint32_t dsa; uint32_t dta; uint32_t dtc; uint32_t sd; uint32_t drt; uint32_t reserved[2]; }; /* Size of allocations for hardware descriptor blocks. */ #define JZ_DMA_DESC_BLOCK_SIZE PAGE_SIZE #define JZ_DMA_MAX_DESC \ (JZ_DMA_DESC_BLOCK_SIZE / sizeof(struct jz4780_dma_hwdesc)) struct jz4780_dma_desc { struct virt_dma_desc vdesc; struct jz4780_dma_hwdesc *desc; dma_addr_t desc_phys; unsigned int count; enum dma_transaction_type type; uint32_t status; }; struct jz4780_dma_chan { struct virt_dma_chan vchan; unsigned int id; struct dma_pool *desc_pool; uint32_t transfer_type; uint32_t transfer_shift; struct dma_slave_config config; struct jz4780_dma_desc *desc; unsigned int curr_hwdesc; }; struct jz4780_dma_dev { struct dma_device dma_device; void __iomem *base; struct clk *clk; unsigned int irq; uint32_t chan_reserved; struct jz4780_dma_chan chan[JZ_DMA_NR_CHANNELS]; }; struct jz4780_dma_filter_data { struct device_node *of_node; uint32_t transfer_type; int channel; }; static inline struct jz4780_dma_chan *to_jz4780_dma_chan(struct dma_chan *chan) { return container_of(chan, struct jz4780_dma_chan, vchan.chan); } static inline struct jz4780_dma_desc *to_jz4780_dma_desc( struct virt_dma_desc *vdesc) { return container_of(vdesc, struct jz4780_dma_desc, vdesc); } static inline struct jz4780_dma_dev *jz4780_dma_chan_parent( struct jz4780_dma_chan *jzchan) { return container_of(jzchan->vchan.chan.device, struct jz4780_dma_dev, dma_device); } static inline uint32_t jz4780_dma_readl(struct jz4780_dma_dev *jzdma, unsigned int reg) { return readl(jzdma->base + reg); } static inline void jz4780_dma_writel(struct jz4780_dma_dev *jzdma, unsigned int reg, uint32_t val) { writel(val, jzdma->base + reg); } static struct jz4780_dma_desc *jz4780_dma_desc_alloc( struct jz4780_dma_chan *jzchan, unsigned int count, enum dma_transaction_type type) { struct jz4780_dma_desc *desc; if (count > JZ_DMA_MAX_DESC) return NULL; desc = kzalloc(sizeof(*desc), GFP_NOWAIT); if (!desc) return NULL; desc->desc = dma_pool_alloc(jzchan->desc_pool, GFP_NOWAIT, &desc->desc_phys); if (!desc->desc) { kfree(desc); return NULL; } desc->count = count; desc->type = type; return desc; } static void jz4780_dma_desc_free(struct virt_dma_desc *vdesc) { struct jz4780_dma_desc *desc = to_jz4780_dma_desc(vdesc); struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(vdesc->tx.chan); dma_pool_free(jzchan->desc_pool, desc->desc, desc->desc_phys); kfree(desc); } static uint32_t jz4780_dma_transfer_size(unsigned long val, uint32_t *shift) { int ord = ffs(val) - 1; /* * 8 byte transfer sizes unsupported so fall back on 4. If it's larger * than the maximum, just limit it. It is perfectly safe to fall back * in this way since we won't exceed the maximum burst size supported * by the device, the only effect is reduced efficiency. This is better * than refusing to perform the request at all. */ if (ord == 3) ord = 2; else if (ord > 7) ord = 7; *shift = ord; switch (ord) { case 0: return JZ_DMA_SIZE_1_BYTE; case 1: return JZ_DMA_SIZE_2_BYTE; case 2: return JZ_DMA_SIZE_4_BYTE; case 4: return JZ_DMA_SIZE_16_BYTE; case 5: return JZ_DMA_SIZE_32_BYTE; case 6: return JZ_DMA_SIZE_64_BYTE; default: return JZ_DMA_SIZE_128_BYTE; } } static int jz4780_dma_setup_hwdesc(struct jz4780_dma_chan *jzchan, struct jz4780_dma_hwdesc *desc, dma_addr_t addr, size_t len, enum dma_transfer_direction direction) { struct dma_slave_config *config = &jzchan->config; uint32_t width, maxburst, tsz; if (direction == DMA_MEM_TO_DEV) { desc->dcm = JZ_DMA_DCM_SAI; desc->dsa = addr; desc->dta = config->dst_addr; desc->drt = jzchan->transfer_type; width = config->dst_addr_width; maxburst = config->dst_maxburst; } else { desc->dcm = JZ_DMA_DCM_DAI; desc->dsa = config->src_addr; desc->dta = addr; desc->drt = jzchan->transfer_type; width = config->src_addr_width; maxburst = config->src_maxburst; } /* * This calculates the maximum transfer size that can be used with the * given address, length, width and maximum burst size. The address * must be aligned to the transfer size, the total length must be * divisible by the transfer size, and we must not use more than the * maximum burst specified by the user. */ tsz = jz4780_dma_transfer_size(addr | len | (width * maxburst), &jzchan->transfer_shift); switch (width) { case DMA_SLAVE_BUSWIDTH_1_BYTE: case DMA_SLAVE_BUSWIDTH_2_BYTES: break; case DMA_SLAVE_BUSWIDTH_4_BYTES: width = JZ_DMA_WIDTH_32_BIT; break; default: return -EINVAL; } desc->dcm |= tsz << JZ_DMA_DCM_TSZ_SHIFT; desc->dcm |= width << JZ_DMA_DCM_SP_SHIFT; desc->dcm |= width << JZ_DMA_DCM_DP_SHIFT; desc->dtc = len >> jzchan->transfer_shift; return 0; } static struct dma_async_tx_descriptor *jz4780_dma_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 jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); struct jz4780_dma_desc *desc; unsigned int i; int err; desc = jz4780_dma_desc_alloc(jzchan, sg_len, DMA_SLAVE); if (!desc) return NULL; for (i = 0; i < sg_len; i++) { err = jz4780_dma_setup_hwdesc(jzchan, &desc->desc[i], sg_dma_address(&sgl[i]), sg_dma_len(&sgl[i]), direction); if (err < 0) { jz4780_dma_desc_free(&jzchan->desc->vdesc); return NULL; } desc->desc[i].dcm |= JZ_DMA_DCM_TIE; if (i != (sg_len - 1)) { /* Automatically proceeed to the next descriptor. */ desc->desc[i].dcm |= JZ_DMA_DCM_LINK; /* * The upper 8 bits of the DTC field in the descriptor * must be set to (offset from descriptor base of next * descriptor >> 4). */ desc->desc[i].dtc |= (((i + 1) * sizeof(*desc->desc)) >> 4) << 24; } } return vchan_tx_prep(&jzchan->vchan, &desc->vdesc, flags); } static struct dma_async_tx_descriptor *jz4780_dma_prep_dma_cyclic( struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len, size_t period_len, enum dma_transfer_direction direction, unsigned long flags) { struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); struct jz4780_dma_desc *desc; unsigned int periods, i; int err; if (buf_len % period_len) return NULL; periods = buf_len / period_len; desc = jz4780_dma_desc_alloc(jzchan, periods, DMA_CYCLIC); if (!desc) return NULL; for (i = 0; i < periods; i++) { err = jz4780_dma_setup_hwdesc(jzchan, &desc->desc[i], buf_addr, period_len, direction); if (err < 0) { jz4780_dma_desc_free(&jzchan->desc->vdesc); return NULL; } buf_addr += period_len; /* * Set the link bit to indicate that the controller should * automatically proceed to the next descriptor. In * jz4780_dma_begin(), this will be cleared if we need to issue * an interrupt after each period. */ desc->desc[i].dcm |= JZ_DMA_DCM_TIE | JZ_DMA_DCM_LINK; /* * The upper 8 bits of the DTC field in the descriptor must be * set to (offset from descriptor base of next descriptor >> 4). * If this is the last descriptor, link it back to the first, * i.e. leave offset set to 0, otherwise point to the next one. */ if (i != (periods - 1)) { desc->desc[i].dtc |= (((i + 1) * sizeof(*desc->desc)) >> 4) << 24; } } return vchan_tx_prep(&jzchan->vchan, &desc->vdesc, flags); } static struct dma_async_tx_descriptor *jz4780_dma_prep_dma_memcpy( struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, size_t len, unsigned long flags) { struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); struct jz4780_dma_desc *desc; uint32_t tsz; desc = jz4780_dma_desc_alloc(jzchan, 1, DMA_MEMCPY); if (!desc) return NULL; tsz = jz4780_dma_transfer_size(dest | src | len, &jzchan->transfer_shift); desc->desc[0].dsa = src; desc->desc[0].dta = dest; desc->desc[0].drt = JZ_DMA_DRT_AUTO; desc->desc[0].dcm = JZ_DMA_DCM_TIE | JZ_DMA_DCM_SAI | JZ_DMA_DCM_DAI | tsz << JZ_DMA_DCM_TSZ_SHIFT | JZ_DMA_WIDTH_32_BIT << JZ_DMA_DCM_SP_SHIFT | JZ_DMA_WIDTH_32_BIT << JZ_DMA_DCM_DP_SHIFT; desc->desc[0].dtc = len >> jzchan->transfer_shift; return vchan_tx_prep(&jzchan->vchan, &desc->vdesc, flags); } static void jz4780_dma_begin(struct jz4780_dma_chan *jzchan) { struct jz4780_dma_dev *jzdma = jz4780_dma_chan_parent(jzchan); struct virt_dma_desc *vdesc; unsigned int i; dma_addr_t desc_phys; if (!jzchan->desc) { vdesc = vchan_next_desc(&jzchan->vchan); if (!vdesc) return; list_del(&vdesc->node); jzchan->desc = to_jz4780_dma_desc(vdesc); jzchan->curr_hwdesc = 0; if (jzchan->desc->type == DMA_CYCLIC && vdesc->tx.callback) { /* * The DMA controller doesn't support triggering an * interrupt after processing each descriptor, only * after processing an entire terminated list of * descriptors. For a cyclic DMA setup the list of * descriptors is not terminated so we can never get an * interrupt. * * If the user requested a callback for a cyclic DMA * setup then we workaround this hardware limitation * here by degrading to a set of unlinked descriptors * which we will submit in sequence in response to the * completion of processing the previous descriptor. */ for (i = 0; i < jzchan->desc->count; i++) jzchan->desc->desc[i].dcm &= ~JZ_DMA_DCM_LINK; } } else { /* * There is an existing transfer, therefore this must be one * for which we unlinked the descriptors above. Advance to the * next one in the list. */ jzchan->curr_hwdesc = (jzchan->curr_hwdesc + 1) % jzchan->desc->count; } /* Use 8-word descriptors. */ jz4780_dma_writel(jzdma, JZ_DMA_REG_DCS(jzchan->id), JZ_DMA_DCS_DES8); /* Write descriptor address and initiate descriptor fetch. */ desc_phys = jzchan->desc->desc_phys + (jzchan->curr_hwdesc * sizeof(*jzchan->desc->desc)); jz4780_dma_writel(jzdma, JZ_DMA_REG_DDA(jzchan->id), desc_phys); jz4780_dma_writel(jzdma, JZ_DMA_REG_DDRS, BIT(jzchan->id)); /* Enable the channel. */ jz4780_dma_writel(jzdma, JZ_DMA_REG_DCS(jzchan->id), JZ_DMA_DCS_DES8 | JZ_DMA_DCS_CTE); } static void jz4780_dma_issue_pending(struct dma_chan *chan) { struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); unsigned long flags; spin_lock_irqsave(&jzchan->vchan.lock, flags); if (vchan_issue_pending(&jzchan->vchan) && !jzchan->desc) jz4780_dma_begin(jzchan); spin_unlock_irqrestore(&jzchan->vchan.lock, flags); } static int jz4780_dma_terminate_all(struct dma_chan *chan) { struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); struct jz4780_dma_dev *jzdma = jz4780_dma_chan_parent(jzchan); unsigned long flags; LIST_HEAD(head); spin_lock_irqsave(&jzchan->vchan.lock, flags); /* Clear the DMA status and stop the transfer. */ jz4780_dma_writel(jzdma, JZ_DMA_REG_DCS(jzchan->id), 0); if (jzchan->desc) { jz4780_dma_desc_free(&jzchan->desc->vdesc); jzchan->desc = NULL; } vchan_get_all_descriptors(&jzchan->vchan, &head); spin_unlock_irqrestore(&jzchan->vchan.lock, flags); vchan_dma_desc_free_list(&jzchan->vchan, &head); return 0; } static int jz4780_dma_config(struct dma_chan *chan, struct dma_slave_config *config) { struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); if ((config->src_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES) || (config->dst_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES)) return -EINVAL; /* Copy the reset of the slave configuration, it is used later. */ memcpy(&jzchan->config, config, sizeof(jzchan->config)); return 0; } static size_t jz4780_dma_desc_residue(struct jz4780_dma_chan *jzchan, struct jz4780_dma_desc *desc, unsigned int next_sg) { struct jz4780_dma_dev *jzdma = jz4780_dma_chan_parent(jzchan); unsigned int residue, count; unsigned int i; residue = 0; for (i = next_sg; i < desc->count; i++) residue += desc->desc[i].dtc << jzchan->transfer_shift; if (next_sg != 0) { count = jz4780_dma_readl(jzdma, JZ_DMA_REG_DTC(jzchan->id)); residue += count << jzchan->transfer_shift; } return residue; } static enum dma_status jz4780_dma_tx_status(struct dma_chan *chan, dma_cookie_t cookie, struct dma_tx_state *txstate) { struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); struct virt_dma_desc *vdesc; enum dma_status status; unsigned long flags; status = dma_cookie_status(chan, cookie, txstate); if ((status == DMA_COMPLETE) || (txstate == NULL)) return status; spin_lock_irqsave(&jzchan->vchan.lock, flags); vdesc = vchan_find_desc(&jzchan->vchan, cookie); if (vdesc) { /* On the issued list, so hasn't been processed yet */ txstate->residue = jz4780_dma_desc_residue(jzchan, to_jz4780_dma_desc(vdesc), 0); } else if (cookie == jzchan->desc->vdesc.tx.cookie) { txstate->residue = jz4780_dma_desc_residue(jzchan, jzchan->desc, (jzchan->curr_hwdesc + 1) % jzchan->desc->count); } else txstate->residue = 0; if (vdesc && jzchan->desc && vdesc == &jzchan->desc->vdesc && jzchan->desc->status & (JZ_DMA_DCS_AR | JZ_DMA_DCS_HLT)) status = DMA_ERROR; spin_unlock_irqrestore(&jzchan->vchan.lock, flags); return status; } static void jz4780_dma_chan_irq(struct jz4780_dma_dev *jzdma, struct jz4780_dma_chan *jzchan) { uint32_t dcs; spin_lock(&jzchan->vchan.lock); dcs = jz4780_dma_readl(jzdma, JZ_DMA_REG_DCS(jzchan->id)); jz4780_dma_writel(jzdma, JZ_DMA_REG_DCS(jzchan->id), 0); if (dcs & JZ_DMA_DCS_AR) { dev_warn(&jzchan->vchan.chan.dev->device, "address error (DCS=0x%x)\n", dcs); } if (dcs & JZ_DMA_DCS_HLT) { dev_warn(&jzchan->vchan.chan.dev->device, "channel halt (DCS=0x%x)\n", dcs); } if (jzchan->desc) { jzchan->desc->status = dcs; if ((dcs & (JZ_DMA_DCS_AR | JZ_DMA_DCS_HLT)) == 0) { if (jzchan->desc->type == DMA_CYCLIC) { vchan_cyclic_callback(&jzchan->desc->vdesc); } else { vchan_cookie_complete(&jzchan->desc->vdesc); jzchan->desc = NULL; } jz4780_dma_begin(jzchan); } } else { dev_err(&jzchan->vchan.chan.dev->device, "channel IRQ with no active transfer\n"); } spin_unlock(&jzchan->vchan.lock); } static irqreturn_t jz4780_dma_irq_handler(int irq, void *data) { struct jz4780_dma_dev *jzdma = data; uint32_t pending, dmac; int i; pending = jz4780_dma_readl(jzdma, JZ_DMA_REG_DIRQP); for (i = 0; i < JZ_DMA_NR_CHANNELS; i++) { if (!(pending & (1<<i))) continue; jz4780_dma_chan_irq(jzdma, &jzdma->chan[i]); } /* Clear halt and address error status of all channels. */ dmac = jz4780_dma_readl(jzdma, JZ_DMA_REG_DMAC); dmac &= ~(JZ_DMA_DMAC_HLT | JZ_DMA_DMAC_AR); jz4780_dma_writel(jzdma, JZ_DMA_REG_DMAC, dmac); /* Clear interrupt pending status. */ jz4780_dma_writel(jzdma, JZ_DMA_REG_DIRQP, 0); return IRQ_HANDLED; } static int jz4780_dma_alloc_chan_resources(struct dma_chan *chan) { struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); jzchan->desc_pool = dma_pool_create(dev_name(&chan->dev->device), chan->device->dev, JZ_DMA_DESC_BLOCK_SIZE, PAGE_SIZE, 0); if (!jzchan->desc_pool) { dev_err(&chan->dev->device, "failed to allocate descriptor pool\n"); return -ENOMEM; } return 0; } static void jz4780_dma_free_chan_resources(struct dma_chan *chan) { struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); vchan_free_chan_resources(&jzchan->vchan); dma_pool_destroy(jzchan->desc_pool); jzchan->desc_pool = NULL; } static bool jz4780_dma_filter_fn(struct dma_chan *chan, void *param) { struct jz4780_dma_chan *jzchan = to_jz4780_dma_chan(chan); struct jz4780_dma_dev *jzdma = jz4780_dma_chan_parent(jzchan); struct jz4780_dma_filter_data *data = param; if (jzdma->dma_device.dev->of_node != data->of_node) return false; if (data->channel > -1) { if (data->channel != jzchan->id) return false; } else if (jzdma->chan_reserved & BIT(jzchan->id)) { return false; } jzchan->transfer_type = data->transfer_type; return true; } static struct dma_chan *jz4780_of_dma_xlate(struct of_phandle_args *dma_spec, struct of_dma *ofdma) { struct jz4780_dma_dev *jzdma = ofdma->of_dma_data; dma_cap_mask_t mask = jzdma->dma_device.cap_mask; struct jz4780_dma_filter_data data; if (dma_spec->args_count != 2) return NULL; data.of_node = ofdma->of_node; data.transfer_type = dma_spec->args[0]; data.channel = dma_spec->args[1]; if (data.channel > -1) { if (data.channel >= JZ_DMA_NR_CHANNELS) { dev_err(jzdma->dma_device.dev, "device requested non-existent channel %u\n", data.channel); return NULL; } /* Can only select a channel marked as reserved. */ if (!(jzdma->chan_reserved & BIT(data.channel))) { dev_err(jzdma->dma_device.dev, "device requested unreserved channel %u\n", data.channel); return NULL; } jzdma->chan[data.channel].transfer_type = data.transfer_type; return dma_get_slave_channel( &jzdma->chan[data.channel].vchan.chan); } else { return dma_request_channel(mask, jz4780_dma_filter_fn, &data); } } static int jz4780_dma_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct jz4780_dma_dev *jzdma; struct jz4780_dma_chan *jzchan; struct dma_device *dd; struct resource *res; int i, ret; jzdma = devm_kzalloc(dev, sizeof(*jzdma), GFP_KERNEL); if (!jzdma) return -ENOMEM; platform_set_drvdata(pdev, jzdma); res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) { dev_err(dev, "failed to get I/O memory\n"); return -EINVAL; } jzdma->base = devm_ioremap_resource(dev, res); if (IS_ERR(jzdma->base)) return PTR_ERR(jzdma->base); ret = platform_get_irq(pdev, 0); if (ret < 0) { dev_err(dev, "failed to get IRQ: %d\n", ret); return ret; } jzdma->irq = ret; ret = request_irq(jzdma->irq, jz4780_dma_irq_handler, 0, dev_name(dev), jzdma); if (ret) { dev_err(dev, "failed to request IRQ %u!\n", jzdma->irq); return ret; } jzdma->clk = devm_clk_get(dev, NULL); if (IS_ERR(jzdma->clk)) { dev_err(dev, "failed to get clock\n"); ret = PTR_ERR(jzdma->clk); goto err_free_irq; } clk_prepare_enable(jzdma->clk); /* Property is optional, if it doesn't exist the value will remain 0. */ of_property_read_u32_index(dev->of_node, "ingenic,reserved-channels", 0, &jzdma->chan_reserved); dd = &jzdma->dma_device; dma_cap_set(DMA_MEMCPY, dd->cap_mask); dma_cap_set(DMA_SLAVE, dd->cap_mask); dma_cap_set(DMA_CYCLIC, dd->cap_mask); dd->dev = dev; dd->copy_align = DMAENGINE_ALIGN_4_BYTES; dd->device_alloc_chan_resources = jz4780_dma_alloc_chan_resources; dd->device_free_chan_resources = jz4780_dma_free_chan_resources; dd->device_prep_slave_sg = jz4780_dma_prep_slave_sg; dd->device_prep_dma_cyclic = jz4780_dma_prep_dma_cyclic; dd->device_prep_dma_memcpy = jz4780_dma_prep_dma_memcpy; dd->device_config = jz4780_dma_config; dd->device_terminate_all = jz4780_dma_terminate_all; dd->device_tx_status = jz4780_dma_tx_status; dd->device_issue_pending = jz4780_dma_issue_pending; dd->src_addr_widths = JZ_DMA_BUSWIDTHS; dd->dst_addr_widths = JZ_DMA_BUSWIDTHS; dd->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); dd->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST; /* * Enable DMA controller, mark all channels as not programmable. * Also set the FMSC bit - it increases MSC performance, so it makes * little sense not to enable it. */ jz4780_dma_writel(jzdma, JZ_DMA_REG_DMAC, JZ_DMA_DMAC_DMAE | JZ_DMA_DMAC_FMSC); jz4780_dma_writel(jzdma, JZ_DMA_REG_DMACP, 0); INIT_LIST_HEAD(&dd->channels); for (i = 0; i < JZ_DMA_NR_CHANNELS; i++) { jzchan = &jzdma->chan[i]; jzchan->id = i; vchan_init(&jzchan->vchan, dd); jzchan->vchan.desc_free = jz4780_dma_desc_free; } ret = dma_async_device_register(dd); if (ret) { dev_err(dev, "failed to register device\n"); goto err_disable_clk; } /* Register with OF DMA helpers. */ ret = of_dma_controller_register(dev->of_node, jz4780_of_dma_xlate, jzdma); if (ret) { dev_err(dev, "failed to register OF DMA controller\n"); goto err_unregister_dev; } dev_info(dev, "JZ4780 DMA controller initialised\n"); return 0; err_unregister_dev: dma_async_device_unregister(dd); err_disable_clk: clk_disable_unprepare(jzdma->clk); err_free_irq: free_irq(jzdma->irq, jzdma); return ret; } static int jz4780_dma_remove(struct platform_device *pdev) { struct jz4780_dma_dev *jzdma = platform_get_drvdata(pdev); int i; of_dma_controller_free(pdev->dev.of_node); free_irq(jzdma->irq, jzdma); for (i = 0; i < JZ_DMA_NR_CHANNELS; i++) tasklet_kill(&jzdma->chan[i].vchan.task); dma_async_device_unregister(&jzdma->dma_device); return 0; } static const struct of_device_id jz4780_dma_dt_match[] = { { .compatible = "ingenic,jz4780-dma", .data = NULL }, {}, }; MODULE_DEVICE_TABLE(of, jz4780_dma_dt_match); static struct platform_driver jz4780_dma_driver = { .probe = jz4780_dma_probe, .remove = jz4780_dma_remove, .driver = { .name = "jz4780-dma", .of_match_table = of_match_ptr(jz4780_dma_dt_match), }, }; static int __init jz4780_dma_init(void) { return platform_driver_register(&jz4780_dma_driver); } subsys_initcall(jz4780_dma_init); static void __exit jz4780_dma_exit(void) { platform_driver_unregister(&jz4780_dma_driver); } module_exit(jz4780_dma_exit); MODULE_AUTHOR("Alex Smith <alex@alex-smith.me.uk>"); MODULE_DESCRIPTION("Ingenic JZ4780 DMA controller driver"); MODULE_LICENSE("GPL");