diff options
| -rw-r--r-- | drivers/dma/Kconfig | 6 | ||||
| -rw-r--r-- | drivers/dma/Makefile | 1 | ||||
| -rw-r--r-- | drivers/dma/dma-jz4740.c | 433 |
3 files changed, 440 insertions, 0 deletions
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig index 146a1d864a71..f2b3f0315ea2 100644 --- a/drivers/dma/Kconfig +++ b/drivers/dma/Kconfig @@ -294,6 +294,12 @@ config MMP_PDMA help Support the MMP PDMA engine for PXA and MMP platfrom. +config DMA_JZ4740 + tristate "JZ4740 DMA support" + depends on MACH_JZ4740 + select DMA_ENGINE + select DMA_VIRTUAL_CHANNELS + config DMA_ENGINE bool diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile index 6e2a521fbbe3..5e0f2ef85614 100644 --- a/drivers/dma/Makefile +++ b/drivers/dma/Makefile @@ -38,3 +38,4 @@ obj-$(CONFIG_DMA_SA11X0) += sa11x0-dma.o obj-$(CONFIG_MMP_TDMA) += mmp_tdma.o obj-$(CONFIG_DMA_OMAP) += omap-dma.o obj-$(CONFIG_MMP_PDMA) += mmp_pdma.o +obj-$(CONFIG_DMA_JZ4740) += dma-jz4740.o diff --git a/drivers/dma/dma-jz4740.c b/drivers/dma/dma-jz4740.c new file mode 100644 index 000000000000..3d424341d8fe --- /dev/null +++ b/drivers/dma/dma-jz4740.c @@ -0,0 +1,433 @@ +/* + * Copyright (C) 2013, Lars-Peter Clausen <lars@metafoo.de> + * JZ4740 DMAC support + * + * 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. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 675 Mass Ave, Cambridge, MA 02139, USA. + * + */ + +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/spinlock.h> + +#include <asm/mach-jz4740/dma.h> + +#include "virt-dma.h" + +#define JZ_DMA_NR_CHANS 6 + +struct jz4740_dma_sg { + dma_addr_t addr; + unsigned int len; +}; + +struct jz4740_dma_desc { + struct virt_dma_desc vdesc; + + enum dma_transfer_direction direction; + bool cyclic; + + unsigned int num_sgs; + struct jz4740_dma_sg sg[]; +}; + +struct jz4740_dmaengine_chan { + struct virt_dma_chan vchan; + struct jz4740_dma_chan *jz_chan; + + dma_addr_t fifo_addr; + + struct jz4740_dma_desc *desc; + unsigned int next_sg; +}; + +struct jz4740_dma_dev { + struct dma_device ddev; + + struct jz4740_dmaengine_chan chan[JZ_DMA_NR_CHANS]; +}; + +static struct jz4740_dmaengine_chan *to_jz4740_dma_chan(struct dma_chan *c) +{ + return container_of(c, struct jz4740_dmaengine_chan, vchan.chan); +} + +static struct jz4740_dma_desc *to_jz4740_dma_desc(struct virt_dma_desc *vdesc) +{ + return container_of(vdesc, struct jz4740_dma_desc, vdesc); +} + +static struct jz4740_dma_desc *jz4740_dma_alloc_desc(unsigned int num_sgs) +{ + return kzalloc(sizeof(struct jz4740_dma_desc) + + sizeof(struct jz4740_dma_sg) * num_sgs, GFP_ATOMIC); +} + +static enum jz4740_dma_width jz4740_dma_width(enum dma_slave_buswidth width) +{ + switch (width) { + case DMA_SLAVE_BUSWIDTH_1_BYTE: + return JZ4740_DMA_WIDTH_8BIT; + case DMA_SLAVE_BUSWIDTH_2_BYTES: + return JZ4740_DMA_WIDTH_16BIT; + case DMA_SLAVE_BUSWIDTH_4_BYTES: + return JZ4740_DMA_WIDTH_32BIT; + default: + return JZ4740_DMA_WIDTH_32BIT; + } +} + +static enum jz4740_dma_transfer_size jz4740_dma_maxburst(u32 maxburst) +{ + if (maxburst <= 1) + return JZ4740_DMA_TRANSFER_SIZE_1BYTE; + else if (maxburst <= 3) + return JZ4740_DMA_TRANSFER_SIZE_2BYTE; + else if (maxburst <= 15) + return JZ4740_DMA_TRANSFER_SIZE_4BYTE; + else if (maxburst <= 31) + return JZ4740_DMA_TRANSFER_SIZE_16BYTE; + + return JZ4740_DMA_TRANSFER_SIZE_32BYTE; +} + +static int jz4740_dma_slave_config(struct dma_chan *c, + const struct dma_slave_config *config) +{ + struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c); + struct jz4740_dma_config jzcfg; + + switch (config->direction) { + case DMA_MEM_TO_DEV: + jzcfg.flags = JZ4740_DMA_SRC_AUTOINC; + jzcfg.transfer_size = jz4740_dma_maxburst(config->dst_maxburst); + chan->fifo_addr = config->dst_addr; + break; + case DMA_DEV_TO_MEM: + jzcfg.flags = JZ4740_DMA_DST_AUTOINC; + jzcfg.transfer_size = jz4740_dma_maxburst(config->src_maxburst); + chan->fifo_addr = config->src_addr; + break; + default: + return -EINVAL; + } + + + jzcfg.src_width = jz4740_dma_width(config->src_addr_width); + jzcfg.dst_width = jz4740_dma_width(config->dst_addr_width); + jzcfg.mode = JZ4740_DMA_MODE_SINGLE; + jzcfg.request_type = config->slave_id; + + jz4740_dma_configure(chan->jz_chan, &jzcfg); + + return 0; +} + +static int jz4740_dma_terminate_all(struct dma_chan *c) +{ + struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c); + unsigned long flags; + LIST_HEAD(head); + + spin_lock_irqsave(&chan->vchan.lock, flags); + jz4740_dma_disable(chan->jz_chan); + chan->desc = NULL; + vchan_get_all_descriptors(&chan->vchan, &head); + spin_unlock_irqrestore(&chan->vchan.lock, flags); + + vchan_dma_desc_free_list(&chan->vchan, &head); + + return 0; +} + +static int jz4740_dma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, + unsigned long arg) +{ + struct dma_slave_config *config = (struct dma_slave_config *)arg; + + switch (cmd) { + case DMA_SLAVE_CONFIG: + return jz4740_dma_slave_config(chan, config); + case DMA_TERMINATE_ALL: + return jz4740_dma_terminate_all(chan); + default: + return -ENOSYS; + } +} + +static int jz4740_dma_start_transfer(struct jz4740_dmaengine_chan *chan) +{ + dma_addr_t src_addr, dst_addr; + struct virt_dma_desc *vdesc; + struct jz4740_dma_sg *sg; + + jz4740_dma_disable(chan->jz_chan); + + if (!chan->desc) { + vdesc = vchan_next_desc(&chan->vchan); + if (!vdesc) + return 0; + chan->desc = to_jz4740_dma_desc(vdesc); + chan->next_sg = 0; + } + + if (chan->next_sg == chan->desc->num_sgs) + chan->next_sg = 0; + + sg = &chan->desc->sg[chan->next_sg]; + + if (chan->desc->direction == DMA_MEM_TO_DEV) { + src_addr = sg->addr; + dst_addr = chan->fifo_addr; + } else { + src_addr = chan->fifo_addr; + dst_addr = sg->addr; + } + jz4740_dma_set_src_addr(chan->jz_chan, src_addr); + jz4740_dma_set_dst_addr(chan->jz_chan, dst_addr); + jz4740_dma_set_transfer_count(chan->jz_chan, sg->len); + + chan->next_sg++; + + jz4740_dma_enable(chan->jz_chan); + + return 0; +} + +static void jz4740_dma_complete_cb(struct jz4740_dma_chan *jz_chan, int error, + void *devid) +{ + struct jz4740_dmaengine_chan *chan = devid; + + spin_lock(&chan->vchan.lock); + if (chan->desc) { + if (chan->desc && chan->desc->cyclic) { + vchan_cyclic_callback(&chan->desc->vdesc); + } else { + if (chan->next_sg == chan->desc->num_sgs) { + chan->desc = NULL; + vchan_cookie_complete(&chan->desc->vdesc); + } + } + } + jz4740_dma_start_transfer(chan); + spin_unlock(&chan->vchan.lock); +} + +static void jz4740_dma_issue_pending(struct dma_chan *c) +{ + struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c); + unsigned long flags; + + spin_lock_irqsave(&chan->vchan.lock, flags); + if (vchan_issue_pending(&chan->vchan) && !chan->desc) + jz4740_dma_start_transfer(chan); + spin_unlock_irqrestore(&chan->vchan.lock, flags); +} + +static struct dma_async_tx_descriptor *jz4740_dma_prep_slave_sg( + struct dma_chan *c, struct scatterlist *sgl, + unsigned int sg_len, enum dma_transfer_direction direction, + unsigned long flags, void *context) +{ + struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c); + struct jz4740_dma_desc *desc; + struct scatterlist *sg; + unsigned int i; + + desc = jz4740_dma_alloc_desc(sg_len); + if (!desc) + return NULL; + + for_each_sg(sgl, sg, sg_len, i) { + desc->sg[i].addr = sg_dma_address(sg); + desc->sg[i].len = sg_dma_len(sg); + } + + desc->num_sgs = sg_len; + desc->direction = direction; + desc->cyclic = false; + + return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags); +} + +static struct dma_async_tx_descriptor *jz4740_dma_prep_dma_cyclic( + struct dma_chan *c, dma_addr_t buf_addr, size_t buf_len, + size_t period_len, enum dma_transfer_direction direction, + unsigned long flags, void *context) +{ + struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c); + struct jz4740_dma_desc *desc; + unsigned int num_periods, i; + + if (buf_len % period_len) + return NULL; + + num_periods = buf_len / period_len; + + desc = jz4740_dma_alloc_desc(num_periods); + if (!desc) + return NULL; + + for (i = 0; i < num_periods; i++) { + desc->sg[i].addr = buf_addr; + desc->sg[i].len = period_len; + buf_addr += period_len; + } + + desc->num_sgs = num_periods; + desc->direction = direction; + desc->cyclic = true; + + return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags); +} + +static size_t jz4740_dma_desc_residue(struct jz4740_dmaengine_chan *chan, + struct jz4740_dma_desc *desc, unsigned int next_sg) +{ + size_t residue = 0; + unsigned int i; + + residue = 0; + + for (i = next_sg; i < desc->num_sgs; i++) + residue += desc->sg[i].len; + + if (next_sg != 0) + residue += jz4740_dma_get_residue(chan->jz_chan); + + return residue; +} + +static enum dma_status jz4740_dma_tx_status(struct dma_chan *c, + dma_cookie_t cookie, struct dma_tx_state *state) +{ + struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c); + struct virt_dma_desc *vdesc; + enum dma_status status; + unsigned long flags; + + status = dma_cookie_status(c, cookie, state); + if (status == DMA_SUCCESS || !state) + return status; + + spin_lock_irqsave(&chan->vchan.lock, flags); + vdesc = vchan_find_desc(&chan->vchan, cookie); + if (cookie == chan->desc->vdesc.tx.cookie) { + state->residue = jz4740_dma_desc_residue(chan, chan->desc, + chan->next_sg); + } else if (vdesc) { + state->residue = jz4740_dma_desc_residue(chan, + to_jz4740_dma_desc(vdesc), 0); + } else { + state->residue = 0; + } + spin_unlock_irqrestore(&chan->vchan.lock, flags); + + return status; +} + +static int jz4740_dma_alloc_chan_resources(struct dma_chan *c) +{ + struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c); + + chan->jz_chan = jz4740_dma_request(chan, NULL); + if (!chan->jz_chan) + return -EBUSY; + + jz4740_dma_set_complete_cb(chan->jz_chan, jz4740_dma_complete_cb); + + return 0; +} + +static void jz4740_dma_free_chan_resources(struct dma_chan *c) +{ + struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c); + + vchan_free_chan_resources(&chan->vchan); + jz4740_dma_free(chan->jz_chan); + chan->jz_chan = NULL; +} + +static void jz4740_dma_desc_free(struct virt_dma_desc *vdesc) +{ + kfree(container_of(vdesc, struct jz4740_dma_desc, vdesc)); +} + +static int jz4740_dma_probe(struct platform_device *pdev) +{ + struct jz4740_dmaengine_chan *chan; + struct jz4740_dma_dev *dmadev; + struct dma_device *dd; + unsigned int i; + int ret; + + dmadev = devm_kzalloc(&pdev->dev, sizeof(*dmadev), GFP_KERNEL); + if (!dmadev) + return -EINVAL; + + dd = &dmadev->ddev; + + dma_cap_set(DMA_SLAVE, dd->cap_mask); + dma_cap_set(DMA_CYCLIC, dd->cap_mask); + dd->device_alloc_chan_resources = jz4740_dma_alloc_chan_resources; + dd->device_free_chan_resources = jz4740_dma_free_chan_resources; + dd->device_tx_status = jz4740_dma_tx_status; + dd->device_issue_pending = jz4740_dma_issue_pending; + dd->device_prep_slave_sg = jz4740_dma_prep_slave_sg; + dd->device_prep_dma_cyclic = jz4740_dma_prep_dma_cyclic; + dd->device_control = jz4740_dma_control; + dd->dev = &pdev->dev; + dd->chancnt = JZ_DMA_NR_CHANS; + INIT_LIST_HEAD(&dd->channels); + + for (i = 0; i < dd->chancnt; i++) { + chan = &dmadev->chan[i]; + chan->vchan.desc_free = jz4740_dma_desc_free; + vchan_init(&chan->vchan, dd); + } + + ret = dma_async_device_register(dd); + if (ret) + return ret; + + platform_set_drvdata(pdev, dmadev); + + return 0; +} + +static int jz4740_dma_remove(struct platform_device *pdev) +{ + struct jz4740_dma_dev *dmadev = platform_get_drvdata(pdev); + + dma_async_device_unregister(&dmadev->ddev); + + return 0; +} + +static struct platform_driver jz4740_dma_driver = { + .probe = jz4740_dma_probe, + .remove = jz4740_dma_remove, + .driver = { + .name = "jz4740-dma", + .owner = THIS_MODULE, + }, +}; +module_platform_driver(jz4740_dma_driver); + +MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); +MODULE_DESCRIPTION("JZ4740 DMA driver"); +MODULE_LICENSE("GPLv2"); |