Add DMA Controller driver for RZ/G2L SoC. Based on the work done by Chris Brandt for RZ/A DMA driver. Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx> Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx> --- v3->v4: * Incorporated Vinod and Geert's review comments. v2->v3: * No change v1->v2: * Started using virtual DMAC. v1: * https://patchwork.kernel.org/project/linux-renesas-soc/patch/20210611113642.18457-4-biju.das.jz@xxxxxxxxxxxxxx/ --- drivers/dma/sh/Kconfig | 9 + drivers/dma/sh/Makefile | 1 + drivers/dma/sh/rz-dmac.c | 929 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 939 insertions(+) create mode 100644 drivers/dma/sh/rz-dmac.c diff --git a/drivers/dma/sh/Kconfig b/drivers/dma/sh/Kconfig index 13437323a85b..1942b0fa9291 100644 --- a/drivers/dma/sh/Kconfig +++ b/drivers/dma/sh/Kconfig @@ -47,3 +47,12 @@ config RENESAS_USB_DMAC help This driver supports the USB-DMA controller found in the Renesas SoCs. + +config RZ_DMAC + tristate "Renesas RZ/G2L Controller" + depends on ARCH_R9A07G044 || COMPILE_TEST + select RENESAS_DMA + select DMA_VIRTUAL_CHANNELS + help + This driver supports the general purpose DMA controller found in the + Renesas RZ/G2L SoC variants. diff --git a/drivers/dma/sh/Makefile b/drivers/dma/sh/Makefile index abdf10341725..360ab6d25e76 100644 --- a/drivers/dma/sh/Makefile +++ b/drivers/dma/sh/Makefile @@ -15,3 +15,4 @@ obj-$(CONFIG_SH_DMAE) += shdma.o obj-$(CONFIG_RCAR_DMAC) += rcar-dmac.o obj-$(CONFIG_RENESAS_USB_DMAC) += usb-dmac.o +obj-$(CONFIG_RZ_DMAC) += rz-dmac.o diff --git a/drivers/dma/sh/rz-dmac.c b/drivers/dma/sh/rz-dmac.c new file mode 100644 index 000000000000..60ba4fa7d0c7 --- /dev/null +++ b/drivers/dma/sh/rz-dmac.c @@ -0,0 +1,929 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Renesas RZ/G2L Controller Driver + * + * Based on imx-dma.c + * + * Copyright (C) 2021 Renesas Electronics Corp. + * Copyright 2010 Sascha Hauer, Pengutronix <s.hauer@xxxxxxxxxxxxxx> + * Copyright 2012 Javier Martin, Vista Silicon <javier.martin@xxxxxxxxxxxxxxxxx> + */ + +#include <linux/dma-mapping.h> +#include <linux/dmaengine.h> +#include <linux/interrupt.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_dma.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/spinlock.h> + +#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; + int valid; + 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_SEL(bits) ((bits) & 0x07) +#define CHCFG_MEM_COPY (0x80400008) + +#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; + channel->lmdesc.valid = 0; + 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; + channel->lmdesc.valid--; + 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; + else + channel->chcfg |= CHCFG_DAD; + + 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%llx dst=0x%llx len=%ld\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 scatterlist *sg; + int i, dma_length = 0; + struct rz_dmac_desc *desc; + + 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); + LIST_HEAD(head); + + 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); + 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 int rz_dmac_config(struct dma_chan *chan, + struct dma_slave_config *config) +{ + struct rz_dmac_chan *channel = to_rz_dmac_chan(chan); + u32 *ch_cfg; + + 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; + + if (config->peripheral_config) { + ch_cfg = config->peripheral_config; + channel->chcfg = *ch_cfg; + } + + 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); + spin_unlock_irqrestore(&channel->vc.lock, flags); + vchan_cookie_complete(&desc->vd); + + spin_lock_irqsave(&channel->vc.lock, flags); + 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; + + channel->mid_rid = dma_spec->args[0]; + + return !test_and_set_bit(dma_spec->args[0], 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 <biju.das.jz@xxxxxxxxxxxxxx>"); +MODULE_LICENSE("GPL v2"); -- 2.17.1
