// SPDX-License-Identifier: GPL-2.0 /* * Renesas RZ/G2L DMA Controller Driver * * Based on imx-dma.c * * Copyright (C) 2021 Renesas Electronics Corp. * Copyright 2010 Sascha Hauer, Pengutronix * Copyright 2012 Javier Martin, Vista Silicon */ #include #include #include #include #include #include #include #include #include #include #include #include "../dmaengine.h" #include "../virt-dma.h" enum rz_dmac_prep_type { RZ_DMAC_DESC_MEMCPY, RZ_DMAC_DESC_SLAVE_SG, }; struct rz_lmdesc { u32 header; u32 sa; u32 da; u32 tb; u32 chcfg; u32 chitvl; u32 chext; u32 nxla; }; struct rz_dmac_desc { struct virt_dma_desc vd; dma_addr_t src; dma_addr_t dest; size_t len; struct list_head node; enum dma_transfer_direction direction; enum rz_dmac_prep_type type; /* For slave sg */ struct scatterlist *sg; unsigned int sgcount; }; #define to_rz_dmac_desc(d) container_of(d, struct rz_dmac_desc, vd) struct rz_dmac_chan { struct virt_dma_chan vc; void __iomem *ch_base; void __iomem *ch_cmn_base; unsigned int index; int irq; struct rz_dmac_desc *desc; int descs_allocated; enum dma_slave_buswidth src_word_size; enum dma_slave_buswidth dst_word_size; dma_addr_t src_per_address; dma_addr_t dst_per_address; u32 chcfg; u32 chctrl; int mid_rid; struct list_head ld_free; struct list_head ld_queue; struct list_head ld_active; struct { struct rz_lmdesc *base; struct rz_lmdesc *head; struct rz_lmdesc *tail; dma_addr_t base_dma; } lmdesc; }; #define to_rz_dmac_chan(c) container_of(c, struct rz_dmac_chan, vc.chan) struct rz_dmac { struct dma_device engine; struct device *dev; void __iomem *base; void __iomem *ext_base; unsigned int n_channels; struct rz_dmac_chan *channels; DECLARE_BITMAP(modules, 1024); }; #define to_rz_dmac(d) container_of(d, struct rz_dmac, engine) /* * ----------------------------------------------------------------------------- * Registers */ #define CHSTAT 0x0024 #define CHCTRL 0x0028 #define CHCFG 0x002c #define NXLA 0x0038 #define DCTRL 0x0000 #define EACH_CHANNEL_OFFSET 0x0040 #define CHANNEL_0_7_OFFSET 0x0000 #define CHANNEL_0_7_COMMON_BASE 0x0300 #define CHANNEL_8_15_OFFSET 0x0400 #define CHANNEL_8_15_COMMON_BASE 0x0700 #define CHSTAT_ER BIT(4) #define CHSTAT_EN BIT(0) #define CHCTRL_CLRINTMSK BIT(17) #define CHCTRL_CLRSUS BIT(9) #define CHCTRL_CLRTC BIT(6) #define CHCTRL_CLREND BIT(5) #define CHCTRL_CLRRQ BIT(4) #define CHCTRL_SWRST BIT(3) #define CHCTRL_STG BIT(2) #define CHCTRL_CLREN BIT(1) #define CHCTRL_SETEN BIT(0) #define CHCTRL_DEFAULT (CHCTRL_CLRINTMSK | CHCTRL_CLRSUS | \ CHCTRL_CLRTC | CHCTRL_CLREND | \ CHCTRL_CLRRQ | CHCTRL_SWRST | \ CHCTRL_CLREN) #define CHCFG_DMS BIT(31) #define CHCFG_DEM BIT(24) #define CHCFG_DAD BIT(21) #define CHCFG_SAD BIT(20) #define CHCFG_REQD BIT(3) #define CHCFG_SEL(bits) ((bits) & 0x07) #define CHCFG_MEM_COPY (0x80400008) #define CHCFG_FILL_DDS(a) (((a) << 16) & GENMASK(19, 16)) #define CHCFG_FILL_SDS(a) (((a) << 12) & GENMASK(15, 12)) #define CHCFG_FILL_TM(a) (((a) & BIT(5)) << 22) #define CHCFG_FILL_AM(a) (((a) & GENMASK(4, 2)) << 6) #define CHCFG_FILL_LVL(a) (((a) & BIT(1)) << 5) #define CHCFG_FILL_HIEN(a) (((a) & BIT(0)) << 5) #define MID_RID_MASK GENMASK(9, 0) #define CHCFG_MASK GENMASK(15, 10) #define CHCFG_DS_INVALID 0xFF #define DCTRL_LVINT BIT(1) #define DCTRL_PR BIT(0) #define DCTRL_DEFAULT (DCTRL_LVINT | DCTRL_PR) /* LINK MODE DESCRIPTOR */ #define HEADER_LV BIT(0) #define RZ_DMAC_MAX_CHAN_DESCRIPTORS 16 #define RZ_DMAC_MAX_CHANNELS 16 #define DMAC_NR_LMDESC 64 /* * ----------------------------------------------------------------------------- * Device access */ static void rz_dmac_writel(struct rz_dmac *dmac, unsigned int val, unsigned int offset) { writel(val, dmac->base + offset); } static void rz_dmac_ext_writel(struct rz_dmac *dmac, unsigned int val, unsigned int offset) { writel(val, dmac->ext_base + offset); } static u32 rz_dmac_ext_readl(struct rz_dmac *dmac, unsigned int offset) { return readl(dmac->ext_base + offset); } static void rz_dmac_ch_writel(struct rz_dmac_chan *channel, unsigned int val, unsigned int offset, int which) { if (which) writel(val, channel->ch_base + offset); else writel(val, channel->ch_cmn_base + offset); } static u32 rz_dmac_ch_readl(struct rz_dmac_chan *channel, unsigned int offset, int which) { if (which) return readl(channel->ch_base + offset); else return readl(channel->ch_cmn_base + offset); } /* * ----------------------------------------------------------------------------- * Initialization */ static void rz_lmdesc_setup(struct rz_dmac_chan *channel, struct rz_lmdesc *lmdesc) { u32 nxla; channel->lmdesc.base = lmdesc; channel->lmdesc.head = lmdesc; channel->lmdesc.tail = lmdesc; nxla = channel->lmdesc.base_dma; while (lmdesc < (channel->lmdesc.base + (DMAC_NR_LMDESC - 1))) { lmdesc->header = 0; nxla += sizeof(*lmdesc); lmdesc->nxla = nxla; lmdesc++; } lmdesc->header = 0; lmdesc->nxla = channel->lmdesc.base_dma; } /* * ----------------------------------------------------------------------------- * Descriptors preparation */ static void rz_dmac_lmdesc_recycle(struct rz_dmac_chan *channel) { struct rz_lmdesc *lmdesc = channel->lmdesc.head; while (!(lmdesc->header & HEADER_LV)) { lmdesc->header = 0; lmdesc++; if (lmdesc >= (channel->lmdesc.base + DMAC_NR_LMDESC)) lmdesc = channel->lmdesc.base; } channel->lmdesc.head = lmdesc; } static void rz_dmac_enable_hw(struct rz_dmac_chan *channel) { struct dma_chan *chan = &channel->vc.chan; struct rz_dmac *dmac = to_rz_dmac(chan->device); unsigned long flags; u32 nxla; u32 chctrl; u32 chstat; dev_dbg(dmac->dev, "%s channel %d\n", __func__, channel->index); local_irq_save(flags); rz_dmac_lmdesc_recycle(channel); nxla = channel->lmdesc.base_dma + (sizeof(struct rz_lmdesc) * (channel->lmdesc.head - channel->lmdesc.base)); chstat = rz_dmac_ch_readl(channel, CHSTAT, 1); if (!(chstat & CHSTAT_EN)) { chctrl = (channel->chctrl | CHCTRL_SETEN); rz_dmac_ch_writel(channel, nxla, NXLA, 1); rz_dmac_ch_writel(channel, channel->chcfg, CHCFG, 1); rz_dmac_ch_writel(channel, CHCTRL_SWRST, CHCTRL, 1); rz_dmac_ch_writel(channel, chctrl, CHCTRL, 1); } local_irq_restore(flags); } static void rz_dmac_disable_hw(struct rz_dmac_chan *channel) { struct dma_chan *chan = &channel->vc.chan; struct rz_dmac *dmac = to_rz_dmac(chan->device); unsigned long flags; dev_dbg(dmac->dev, "%s channel %d\n", __func__, channel->index); local_irq_save(flags); rz_dmac_ch_writel(channel, CHCTRL_DEFAULT, CHCTRL, 1); local_irq_restore(flags); } static void rz_dmac_set_dmars_register(struct rz_dmac *dmac, int nr, u32 dmars) { u32 dmars_offset = (nr / 2) * 4; u32 shift = (nr % 2) * 16; u32 dmars32; dmars32 = rz_dmac_ext_readl(dmac, dmars_offset); dmars32 &= ~(0xffff << shift); dmars32 |= dmars << shift; rz_dmac_ext_writel(dmac, dmars32, dmars_offset); } static void rz_dmac_prepare_desc_for_memcpy(struct rz_dmac_chan *channel) { struct dma_chan *chan = &channel->vc.chan; struct rz_dmac *dmac = to_rz_dmac(chan->device); struct rz_lmdesc *lmdesc = channel->lmdesc.base; struct rz_dmac_desc *d = channel->desc; u32 chcfg = CHCFG_MEM_COPY; lmdesc = channel->lmdesc.tail; /* prepare descriptor */ lmdesc->sa = d->src; lmdesc->da = d->dest; lmdesc->tb = d->len; lmdesc->chcfg = chcfg; lmdesc->chitvl = 0; lmdesc->chext = 0; lmdesc->header = HEADER_LV; rz_dmac_set_dmars_register(dmac, channel->index, 0); channel->chcfg = chcfg; channel->chctrl = CHCTRL_STG | CHCTRL_SETEN; } static void rz_dmac_prepare_descs_for_slave_sg(struct rz_dmac_chan *channel) { struct dma_chan *chan = &channel->vc.chan; struct rz_dmac *dmac = to_rz_dmac(chan->device); struct rz_dmac_desc *d = channel->desc; struct scatterlist *sg, *sgl = d->sg; struct rz_lmdesc *lmdesc; unsigned int i, sg_len = d->sgcount; channel->chcfg |= CHCFG_SEL(channel->index) | CHCFG_DEM | CHCFG_DMS; if (d->direction == DMA_DEV_TO_MEM) { channel->chcfg |= CHCFG_SAD; channel->chcfg &= ~CHCFG_REQD; } else { channel->chcfg |= CHCFG_DAD | CHCFG_REQD; } lmdesc = channel->lmdesc.tail; for (i = 0, sg = sgl; i < sg_len; i++, sg = sg_next(sg)) { if (d->direction == DMA_DEV_TO_MEM) { lmdesc->sa = channel->src_per_address; lmdesc->da = sg_dma_address(sg); } else { lmdesc->sa = sg_dma_address(sg); lmdesc->da = channel->dst_per_address; } lmdesc->tb = sg_dma_len(sg); lmdesc->chitvl = 0; lmdesc->chext = 0; if (i == (sg_len - 1)) { lmdesc->chcfg = (channel->chcfg & ~CHCFG_DEM); lmdesc->header = HEADER_LV; } else { lmdesc->chcfg = channel->chcfg; lmdesc->header = HEADER_LV; } if (++lmdesc >= (channel->lmdesc.base + DMAC_NR_LMDESC)) lmdesc = channel->lmdesc.base; } channel->lmdesc.tail = lmdesc; rz_dmac_set_dmars_register(dmac, channel->index, channel->mid_rid); channel->chctrl = CHCTRL_SETEN; } static int rz_dmac_xfer_desc(struct rz_dmac_chan *chan) { struct rz_dmac_desc *d = chan->desc; struct virt_dma_desc *vd; vd = vchan_next_desc(&chan->vc); if (!vd) return 0; list_del(&vd->node); switch (d->type) { case RZ_DMAC_DESC_MEMCPY: rz_dmac_prepare_desc_for_memcpy(chan); break; case RZ_DMAC_DESC_SLAVE_SG: rz_dmac_prepare_descs_for_slave_sg(chan); break; default: return -EINVAL; } rz_dmac_enable_hw(chan); return 0; } /* * ----------------------------------------------------------------------------- * DMA engine operations */ static int rz_dmac_alloc_chan_resources(struct dma_chan *chan) { struct rz_dmac_chan *channel = to_rz_dmac_chan(chan); while (channel->descs_allocated < RZ_DMAC_MAX_CHAN_DESCRIPTORS) { struct rz_dmac_desc *desc; desc = kzalloc(sizeof(*desc), GFP_KERNEL); if (!desc) break; list_add_tail(&desc->node, &channel->ld_free); channel->descs_allocated++; } if (!channel->descs_allocated) return -ENOMEM; return channel->descs_allocated; } static void rz_dmac_free_chan_resources(struct dma_chan *chan) { struct rz_dmac_chan *channel = to_rz_dmac_chan(chan); struct rz_dmac *dmac = to_rz_dmac(chan->device); struct rz_lmdesc *lmdesc = channel->lmdesc.base; struct rz_dmac_desc *desc, *_desc; unsigned long flags; unsigned int i; spin_lock_irqsave(&channel->vc.lock, flags); for (i = 0; i < DMAC_NR_LMDESC; i++) lmdesc[i].header = 0; rz_dmac_disable_hw(channel); list_splice_tail_init(&channel->ld_active, &channel->ld_free); list_splice_tail_init(&channel->ld_queue, &channel->ld_free); if (channel->mid_rid >= 0) { clear_bit(channel->mid_rid, dmac->modules); channel->mid_rid = -EINVAL; } spin_unlock_irqrestore(&channel->vc.lock, flags); list_for_each_entry_safe(desc, _desc, &channel->ld_free, node) { kfree(desc); channel->descs_allocated--; } INIT_LIST_HEAD(&channel->ld_free); vchan_free_chan_resources(&channel->vc); } static struct dma_async_tx_descriptor * rz_dmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, size_t len, unsigned long flags) { struct rz_dmac_chan *channel = to_rz_dmac_chan(chan); struct rz_dmac *dmac = to_rz_dmac(chan->device); struct rz_dmac_desc *desc; dev_dbg(dmac->dev, "%s channel: %d src=0x%pad dst=0x%pad len=%zu\n", __func__, channel->index, &src, &dest, len); if (list_empty(&channel->ld_free)) return NULL; desc = list_first_entry(&channel->ld_free, struct rz_dmac_desc, node); desc->type = RZ_DMAC_DESC_MEMCPY; desc->src = src; desc->dest = dest; desc->len = len; desc->direction = DMA_MEM_TO_MEM; list_move_tail(channel->ld_free.next, &channel->ld_queue); return vchan_tx_prep(&channel->vc, &desc->vd, flags); } static struct dma_async_tx_descriptor * rz_dmac_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 rz_dmac_chan *channel = to_rz_dmac_chan(chan); struct rz_dmac_desc *desc; struct scatterlist *sg; int dma_length = 0; int i = 0; if (list_empty(&channel->ld_free)) return NULL; desc = list_first_entry(&channel->ld_free, struct rz_dmac_desc, node); for_each_sg(sgl, sg, sg_len, i) { dma_length += sg_dma_len(sg); } desc->type = RZ_DMAC_DESC_SLAVE_SG; desc->sg = sgl; desc->sgcount = sg_len; desc->len = dma_length; desc->direction = direction; if (direction == DMA_DEV_TO_MEM) desc->src = channel->src_per_address; else desc->dest = channel->dst_per_address; list_move_tail(channel->ld_free.next, &channel->ld_queue); return vchan_tx_prep(&channel->vc, &desc->vd, flags); } static int rz_dmac_terminate_all(struct dma_chan *chan) { struct rz_dmac_chan *channel = to_rz_dmac_chan(chan); unsigned long flags; LIST_HEAD(head); rz_dmac_disable_hw(channel); spin_lock_irqsave(&channel->vc.lock, flags); list_splice_tail_init(&channel->ld_active, &channel->ld_free); list_splice_tail_init(&channel->ld_queue, &channel->ld_free); spin_unlock_irqrestore(&channel->vc.lock, flags); vchan_get_all_descriptors(&channel->vc, &head); vchan_dma_desc_free_list(&channel->vc, &head); return 0; } static void rz_dmac_issue_pending(struct dma_chan *chan) { struct rz_dmac_chan *channel = to_rz_dmac_chan(chan); struct rz_dmac *dmac = to_rz_dmac(chan->device); struct rz_dmac_desc *desc; unsigned long flags; spin_lock_irqsave(&channel->vc.lock, flags); if (!list_empty(&channel->ld_queue)) { desc = list_first_entry(&channel->ld_queue, struct rz_dmac_desc, node); channel->desc = desc; if (vchan_issue_pending(&channel->vc)) { if (rz_dmac_xfer_desc(channel) < 0) dev_warn(dmac->dev, "ch: %d couldn't issue DMA xfer\n", channel->index); else list_move_tail(channel->ld_queue.next, &channel->ld_active); } } spin_unlock_irqrestore(&channel->vc.lock, flags); } static u8 rz_dmac_ds_to_val_mapping(enum dma_slave_buswidth ds) { u8 i; const enum dma_slave_buswidth ds_lut[] = { DMA_SLAVE_BUSWIDTH_1_BYTE, DMA_SLAVE_BUSWIDTH_2_BYTES, DMA_SLAVE_BUSWIDTH_4_BYTES, DMA_SLAVE_BUSWIDTH_8_BYTES, DMA_SLAVE_BUSWIDTH_16_BYTES, DMA_SLAVE_BUSWIDTH_32_BYTES, DMA_SLAVE_BUSWIDTH_64_BYTES, DMA_SLAVE_BUSWIDTH_128_BYTES, }; for (i = 0; i < ARRAY_SIZE(ds_lut); i++) { if (ds_lut[i] == ds) return i; } return CHCFG_DS_INVALID; } static int rz_dmac_config(struct dma_chan *chan, struct dma_slave_config *config) { struct rz_dmac_chan *channel = to_rz_dmac_chan(chan); u32 val; channel->src_per_address = config->src_addr; channel->src_word_size = config->src_addr_width; channel->dst_per_address = config->dst_addr; channel->dst_word_size = config->dst_addr_width; val = rz_dmac_ds_to_val_mapping(config->dst_addr_width); if (val == CHCFG_DS_INVALID) return -EINVAL; channel->chcfg |= CHCFG_FILL_DDS(val); val = rz_dmac_ds_to_val_mapping(config->src_addr_width); if (val == CHCFG_DS_INVALID) return -EINVAL; channel->chcfg |= CHCFG_FILL_SDS(val); return 0; } static void rz_dmac_virt_desc_free(struct virt_dma_desc *vd) { /* * Place holder * Descriptor allocation is done during alloc_chan_resources and * get freed during free_chan_resources. * list is used to manage the descriptors and avoid any memory * allocation/free during DMA read/write. */ } /* * ----------------------------------------------------------------------------- * IRQ handling */ static void rz_dmac_irq_handle_channel(struct rz_dmac_chan *channel) { struct dma_chan *chan = &channel->vc.chan; struct rz_dmac *dmac = to_rz_dmac(chan->device); u32 chstat, chctrl; chstat = rz_dmac_ch_readl(channel, CHSTAT, 1); if (chstat & CHSTAT_ER) { dev_err(dmac->dev, "DMAC err CHSTAT_%d = %08X\n", channel->index, chstat); rz_dmac_ch_writel(channel, CHCTRL_DEFAULT, CHCTRL, 1); goto done; } chctrl = rz_dmac_ch_readl(channel, CHCTRL, 1); rz_dmac_ch_writel(channel, chctrl | CHCTRL_CLREND, CHCTRL, 1); done: return; } static irqreturn_t rz_dmac_irq_handler(int irq, void *dev_id) { struct rz_dmac_chan *channel = dev_id; if (channel) { rz_dmac_irq_handle_channel(channel); return IRQ_WAKE_THREAD; } /* handle DMAERR irq */ return IRQ_HANDLED; } static irqreturn_t rz_dmac_irq_handler_thread(int irq, void *dev_id) { struct rz_dmac_chan *channel = dev_id; struct rz_dmac_desc *desc = NULL; unsigned long flags; spin_lock_irqsave(&channel->vc.lock, flags); if (list_empty(&channel->ld_active)) { /* Someone might have called terminate all */ goto out; } desc = list_first_entry(&channel->ld_active, struct rz_dmac_desc, node); vchan_cookie_complete(&desc->vd); list_move_tail(channel->ld_active.next, &channel->ld_free); if (!list_empty(&channel->ld_queue)) { desc = list_first_entry(&channel->ld_queue, struct rz_dmac_desc, node); channel->desc = desc; if (rz_dmac_xfer_desc(channel) == 0) list_move_tail(channel->ld_queue.next, &channel->ld_active); } out: spin_unlock_irqrestore(&channel->vc.lock, flags); return IRQ_HANDLED; } /* * ----------------------------------------------------------------------------- * OF xlate and channel filter */ static bool rz_dmac_chan_filter(struct dma_chan *chan, void *arg) { struct rz_dmac_chan *channel = to_rz_dmac_chan(chan); struct rz_dmac *dmac = to_rz_dmac(chan->device); struct of_phandle_args *dma_spec = arg; u32 ch_cfg; channel->mid_rid = dma_spec->args[0] & MID_RID_MASK; ch_cfg = (dma_spec->args[0] & CHCFG_MASK) >> 10; channel->chcfg = CHCFG_FILL_TM(ch_cfg) | CHCFG_FILL_AM(ch_cfg) | CHCFG_FILL_LVL(ch_cfg) | CHCFG_FILL_HIEN(ch_cfg); return !test_and_set_bit(channel->mid_rid, dmac->modules); } static struct dma_chan *rz_dmac_of_xlate(struct of_phandle_args *dma_spec, struct of_dma *ofdma) { dma_cap_mask_t mask; if (dma_spec->args_count != 1) return NULL; /* Only slave DMA channels can be allocated via DT */ dma_cap_zero(mask); dma_cap_set(DMA_SLAVE, mask); return dma_request_channel(mask, rz_dmac_chan_filter, dma_spec); } /* * ----------------------------------------------------------------------------- * Probe and remove */ static int rz_dmac_chan_probe(struct rz_dmac *dmac, struct rz_dmac_chan *channel, unsigned int index) { struct platform_device *pdev = to_platform_device(dmac->dev); struct rz_lmdesc *lmdesc; char pdev_irqname[5]; char *irqname; int ret; channel->index = index; channel->mid_rid = -EINVAL; /* Request the channel interrupt. */ sprintf(pdev_irqname, "ch%u", index); channel->irq = platform_get_irq_byname(pdev, pdev_irqname); if (channel->irq < 0) return channel->irq; irqname = devm_kasprintf(dmac->dev, GFP_KERNEL, "%s:%u", dev_name(dmac->dev), index); if (!irqname) return -ENOMEM; ret = devm_request_threaded_irq(dmac->dev, channel->irq, rz_dmac_irq_handler, rz_dmac_irq_handler_thread, 0, irqname, channel); if (ret) { dev_err(dmac->dev, "failed to request IRQ %u (%d)\n", channel->irq, ret); return ret; } /* Set io base address for each channel */ if (index < 8) { channel->ch_base = dmac->base + CHANNEL_0_7_OFFSET + EACH_CHANNEL_OFFSET * index; channel->ch_cmn_base = dmac->base + CHANNEL_0_7_COMMON_BASE; } else { channel->ch_base = dmac->base + CHANNEL_8_15_OFFSET + EACH_CHANNEL_OFFSET * (index - 8); channel->ch_cmn_base = dmac->base + CHANNEL_8_15_COMMON_BASE; } /* Allocate descriptors */ lmdesc = dma_alloc_coherent(&pdev->dev, sizeof(struct rz_lmdesc) * DMAC_NR_LMDESC, &channel->lmdesc.base_dma, GFP_KERNEL); if (!lmdesc) { dev_err(&pdev->dev, "Can't allocate memory (lmdesc)\n"); return -ENOMEM; } rz_lmdesc_setup(channel, lmdesc); /* Initialize register for each channel */ rz_dmac_ch_writel(channel, CHCTRL_DEFAULT, CHCTRL, 1); channel->vc.desc_free = rz_dmac_virt_desc_free; vchan_init(&channel->vc, &dmac->engine); INIT_LIST_HEAD(&channel->ld_queue); INIT_LIST_HEAD(&channel->ld_free); INIT_LIST_HEAD(&channel->ld_active); return 0; } static int rz_dmac_parse_of(struct device *dev, struct rz_dmac *dmac) { struct device_node *np = dev->of_node; int ret; ret = of_property_read_u32(np, "dma-channels", &dmac->n_channels); if (ret < 0) { dev_err(dev, "unable to read dma-channels property\n"); return ret; } if (!dmac->n_channels || dmac->n_channels > RZ_DMAC_MAX_CHANNELS) { dev_err(dev, "invalid number of channels %u\n", dmac->n_channels); return -EINVAL; } return 0; } static int rz_dmac_probe(struct platform_device *pdev) { const char *irqname = "error"; struct dma_device *engine; struct rz_dmac *dmac; int channel_num; unsigned int i; int ret; int irq; dmac = devm_kzalloc(&pdev->dev, sizeof(*dmac), GFP_KERNEL); if (!dmac) return -ENOMEM; dmac->dev = &pdev->dev; platform_set_drvdata(pdev, dmac); ret = rz_dmac_parse_of(&pdev->dev, dmac); if (ret < 0) return ret; dmac->channels = devm_kcalloc(&pdev->dev, dmac->n_channels, sizeof(*dmac->channels), GFP_KERNEL); if (!dmac->channels) return -ENOMEM; /* Request resources */ dmac->base = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(dmac->base)) return PTR_ERR(dmac->base); dmac->ext_base = devm_platform_ioremap_resource(pdev, 1); if (IS_ERR(dmac->ext_base)) return PTR_ERR(dmac->ext_base); /* Register interrupt handler for error */ irq = platform_get_irq_byname(pdev, irqname); if (irq < 0) return irq; ret = devm_request_irq(&pdev->dev, irq, rz_dmac_irq_handler, 0, irqname, NULL); if (ret) { dev_err(&pdev->dev, "failed to request IRQ %u (%d)\n", irq, ret); return ret; } /* Initialize the channels. */ INIT_LIST_HEAD(&dmac->engine.channels); for (i = 0; i < dmac->n_channels; i++) { ret = rz_dmac_chan_probe(dmac, &dmac->channels[i], i); if (ret < 0) goto err; } /* Register the DMAC as a DMA provider for DT. */ ret = of_dma_controller_register(pdev->dev.of_node, rz_dmac_of_xlate, NULL); if (ret < 0) goto err; /* Register the DMA engine device. */ engine = &dmac->engine; dma_cap_set(DMA_SLAVE, engine->cap_mask); dma_cap_set(DMA_MEMCPY, engine->cap_mask); rz_dmac_writel(dmac, DCTRL_DEFAULT, CHANNEL_0_7_COMMON_BASE + DCTRL); rz_dmac_writel(dmac, DCTRL_DEFAULT, CHANNEL_8_15_COMMON_BASE + DCTRL); engine->dev = &pdev->dev; engine->device_alloc_chan_resources = rz_dmac_alloc_chan_resources; engine->device_free_chan_resources = rz_dmac_free_chan_resources; engine->device_tx_status = dma_cookie_status; engine->device_prep_slave_sg = rz_dmac_prep_slave_sg; engine->device_prep_dma_memcpy = rz_dmac_prep_dma_memcpy; engine->device_config = rz_dmac_config; engine->device_terminate_all = rz_dmac_terminate_all; engine->device_issue_pending = rz_dmac_issue_pending; engine->copy_align = DMAENGINE_ALIGN_1_BYTE; dma_set_max_seg_size(engine->dev, U32_MAX); ret = dma_async_device_register(engine); if (ret < 0) { dev_err(&pdev->dev, "unable to register\n"); goto dma_register_err; } return 0; dma_register_err: of_dma_controller_free(pdev->dev.of_node); err: channel_num = i ? i - 1 : 0; for (i = 0; i < channel_num; i++) { struct rz_dmac_chan *channel = &dmac->channels[i]; dma_free_coherent(NULL, sizeof(struct rz_lmdesc) * DMAC_NR_LMDESC, channel->lmdesc.base, channel->lmdesc.base_dma); } return ret; } static int rz_dmac_remove(struct platform_device *pdev) { struct rz_dmac *dmac = platform_get_drvdata(pdev); unsigned int i; for (i = 0; i < dmac->n_channels; i++) { struct rz_dmac_chan *channel = &dmac->channels[i]; dma_free_coherent(NULL, sizeof(struct rz_lmdesc) * DMAC_NR_LMDESC, channel->lmdesc.base, channel->lmdesc.base_dma); } of_dma_controller_free(pdev->dev.of_node); dma_async_device_unregister(&dmac->engine); return 0; } static const struct of_device_id of_rz_dmac_match[] = { { .compatible = "renesas,rz-dmac", }, { /* Sentinel */ } }; MODULE_DEVICE_TABLE(of, of_rz_dmac_match); static struct platform_driver rz_dmac_driver = { .driver = { .name = "rz-dmac", .of_match_table = of_rz_dmac_match, }, .probe = rz_dmac_probe, .remove = rz_dmac_remove, }; module_platform_driver(rz_dmac_driver); MODULE_DESCRIPTION("Renesas RZ/G2L DMA Controller Driver"); MODULE_AUTHOR("Biju Das "); MODULE_LICENSE("GPL v2");