diff options
-rw-r--r-- | drivers/dma/Kconfig | 10 | ||||
-rw-r--r-- | drivers/dma/Makefile | 1 | ||||
-rw-r--r-- | drivers/dma/edma.c | 671 | ||||
-rw-r--r-- | include/linux/edma.h | 29 |
4 files changed, 711 insertions, 0 deletions
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig index d06ea29..0351719 100644 --- a/drivers/dma/Kconfig +++ b/drivers/dma/Kconfig @@ -208,6 +208,16 @@ config SIRF_DMA help Enable support for the CSR SiRFprimaII DMA engine. +config TI_EDMA + tristate "TI EDMA support" + depends on ARCH_DAVINCI + select DMA_ENGINE + select DMA_VIRTUAL_CHANNELS + default n + help + Enable support for the TI EDMA controller. This DMA + engine is found on TI DaVinci and AM33xx parts. + config ARCH_HAS_ASYNC_TX_FIND_CHANNEL bool diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile index 4cf6b12..f5cf310 100644 --- a/drivers/dma/Makefile +++ b/drivers/dma/Makefile @@ -23,6 +23,7 @@ obj-$(CONFIG_IMX_DMA) += imx-dma.o obj-$(CONFIG_MXS_DMA) += mxs-dma.o obj-$(CONFIG_TIMB_DMA) += timb_dma.o obj-$(CONFIG_SIRF_DMA) += sirf-dma.o +obj-$(CONFIG_TI_EDMA) += edma.o obj-$(CONFIG_STE_DMA40) += ste_dma40.o ste_dma40_ll.o obj-$(CONFIG_TEGRA20_APB_DMA) += tegra20-apb-dma.o obj-$(CONFIG_PL330_DMA) += pl330.o diff --git a/drivers/dma/edma.c b/drivers/dma/edma.c new file mode 100644 index 0000000..05aea3c --- /dev/null +++ b/drivers/dma/edma.c @@ -0,0 +1,671 @@ +/* + * 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 <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/spinlock.h> + +#include <mach/edma.h> + +#include "dmaengine.h" +#include "virt-dma.h" + +/* + * This will go away when the private EDMA API is folded + * into this driver and the platform device(s) are + * instantiated in the arch code. We can only get away + * with this simplification because DA8XX may not be built + * in the same kernel image with other DaVinci parts. This + * avoids having to sprinkle dmaengine driver platform devices + * and data throughout all the existing board files. + */ +#ifdef CONFIG_ARCH_DAVINCI_DA8XX +#define EDMA_CTLRS 2 +#define EDMA_CHANS 32 +#else +#define EDMA_CTLRS 1 +#define EDMA_CHANS 64 +#endif /* CONFIG_ARCH_DAVINCI_DA8XX */ + +/* Max of 16 segments per channel to conserve PaRAM slots */ +#define MAX_NR_SG 16 +#define EDMA_MAX_SLOTS MAX_NR_SG +#define EDMA_DESCRIPTORS 16 + +struct edma_desc { + struct virt_dma_desc vdesc; + struct list_head node; + int absync; + int pset_nr; + struct edmacc_param 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]; + dma_addr_t addr; + int addr_width; + int maxburst; +}; + +struct edma_cc { + int ctlr; + struct dma_device dma_slave; + struct edma_chan slave_chans[EDMA_CHANS]; + int num_slave_chans; + int dummy_slot; +}; + +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 virt_dma_desc *vdesc = vchan_next_desc(&echan->vchan); + struct edma_desc *edesc; + int i; + + if (!vdesc) { + echan->edesc = NULL; + return; + } + + list_del(&vdesc->node); + + echan->edesc = edesc = to_edma_desc(&vdesc->tx); + + /* Write descriptor PaRAM set(s) */ + for (i = 0; i < edesc->pset_nr; i++) { + edma_write_slot(echan->slot[i], &edesc->pset[i]); + dev_dbg(echan->vchan.chan.device->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].opt, + edesc->pset[i].src, + edesc->pset[i].dst, + edesc->pset[i].a_b_cnt, + edesc->pset[i].ccnt, + edesc->pset[i].src_dst_bidx, + edesc->pset[i].src_dst_cidx, + edesc->pset[i].link_bcntrld); + /* Link to the previous slot if not the last set */ + if (i != (edesc->pset_nr - 1)) + edma_link(echan->slot[i], echan->slot[i+1]); + /* Final pset links to the dummy pset */ + else + edma_link(echan->slot[i], echan->ecc->dummy_slot); + } + + edma_start(echan->ch_num); +} + +static int edma_terminate_all(struct edma_chan *echan) +{ + 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) { + echan->edesc = NULL; + edma_stop(echan->ch_num); + } + + 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 edma_chan *echan, + struct dma_slave_config *config) +{ + if ((config->src_addr_width > DMA_SLAVE_BUSWIDTH_4_BYTES) || + (config->dst_addr_width > DMA_SLAVE_BUSWIDTH_4_BYTES)) + return -EINVAL; + + if (config->direction == DMA_MEM_TO_DEV) { + if (config->dst_addr) + echan->addr = config->dst_addr; + if (config->dst_addr_width) + echan->addr_width = config->dst_addr_width; + if (config->dst_maxburst) + echan->maxburst = config->dst_maxburst; + } else if (config->direction == DMA_DEV_TO_MEM) { + if (config->src_addr) + echan->addr = config->src_addr; + if (config->src_addr_width) + echan->addr_width = config->src_addr_width; + if (config->src_maxburst) + echan->maxburst = config->src_maxburst; + } + + return 0; +} + +static int edma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, + unsigned long arg) +{ + int ret = 0; + struct dma_slave_config *config; + struct edma_chan *echan = to_edma_chan(chan); + + switch (cmd) { + case DMA_TERMINATE_ALL: + edma_terminate_all(echan); + break; + case DMA_SLAVE_CONFIG: + config = (struct dma_slave_config *)arg; + ret = edma_slave_config(echan, config); + break; + default: + ret = -ENOSYS; + } + + return ret; +} + +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; + struct scatterlist *sg; + int i; + int acnt, bcnt, ccnt, src, dst, cidx; + int src_bidx, dst_bidx, src_cidx, dst_cidx; + + if (unlikely(!echan || !sgl || !sg_len)) + return NULL; + + if (echan->addr_width == DMA_SLAVE_BUSWIDTH_UNDEFINED) { + dev_err(dev, "Undefined slave buswidth\n"); + return NULL; + } + + if (sg_len > MAX_NR_SG) { + dev_err(dev, "Exceeded max SG segments %d > %d\n", + sg_len, MAX_NR_SG); + return NULL; + } + + edesc = kzalloc(sizeof(*edesc) + sg_len * + sizeof(edesc->pset[0]), GFP_ATOMIC); + if (!edesc) { + dev_dbg(dev, "Failed to allocate a descriptor\n"); + return NULL; + } + + edesc->pset_nr = sg_len; + + for_each_sg(sgl, sg, sg_len, i) { + /* Allocate a PaRAM slot, if needed */ + if (echan->slot[i] < 0) { + echan->slot[i] = + edma_alloc_slot(EDMA_CTLR(echan->ch_num), + EDMA_SLOT_ANY); + if (echan->slot[i] < 0) { + dev_err(dev, "Failed to allocate slot\n"); + return NULL; + } + } + + acnt = echan->addr_width; + + /* + * 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 (echan->maxburst == 1) { + edesc->absync = false; + ccnt = sg_dma_len(sg) / acnt / (SZ_64K - 1); + bcnt = sg_dma_len(sg) / acnt - ccnt * (SZ_64K - 1); + if (bcnt) + ccnt++; + else + bcnt = SZ_64K - 1; + cidx = acnt; + /* + * 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. + */ + } else { + edesc->absync = true; + bcnt = echan->maxburst; + ccnt = sg_dma_len(sg) / (acnt * bcnt); + if (ccnt > (SZ_64K - 1)) { + dev_err(dev, "Exceeded max SG segment size\n"); + return NULL; + } + cidx = acnt * bcnt; + } + + if (direction == DMA_MEM_TO_DEV) { + src = sg_dma_address(sg); + dst = echan->addr; + src_bidx = acnt; + src_cidx = cidx; + dst_bidx = 0; + dst_cidx = 0; + } else { + src = echan->addr; + dst = sg_dma_address(sg); + src_bidx = 0; + src_cidx = 0; + dst_bidx = acnt; + dst_cidx = cidx; + } + + edesc->pset[i].opt = EDMA_TCC(EDMA_CHAN_SLOT(echan->ch_num)); + /* Configure A or AB synchronized transfers */ + if (edesc->absync) + edesc->pset[i].opt |= SYNCDIM; + /* If this is the last set, enable completion interrupt flag */ + if (i == sg_len - 1) + edesc->pset[i].opt |= TCINTEN; + + edesc->pset[i].src = src; + edesc->pset[i].dst = dst; + + edesc->pset[i].src_dst_bidx = (dst_bidx << 16) | src_bidx; + edesc->pset[i].src_dst_cidx = (dst_cidx << 16) | src_cidx; + + edesc->pset[i].a_b_cnt = bcnt << 16 | acnt; + edesc->pset[i].ccnt = ccnt; + edesc->pset[i].link_bcntrld = 0xffffffff; + + } + + 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 device *dev = echan->vchan.chan.device->dev; + struct edma_desc *edesc; + unsigned long flags; + + /* Stop the channel */ + edma_stop(echan->ch_num); + + switch (ch_status) { + case DMA_COMPLETE: + dev_dbg(dev, "transfer complete on channel %d\n", ch_num); + + spin_lock_irqsave(&echan->vchan.lock, flags); + + edesc = echan->edesc; + if (edesc) { + edma_execute(echan); + vchan_cookie_complete(&edesc->vdesc); + } + + spin_unlock_irqrestore(&echan->vchan.lock, flags); + + break; + case DMA_CC_ERROR: + dev_dbg(dev, "transfer error on channel %d\n", ch_num); + break; + default: + break; + } +} + +/* 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->ch_num, edma_callback, + chan, 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_info(dev, "allocated channel for %u:%u\n", + EDMA_CTLR(echan->ch_num), EDMA_CHAN_SLOT(echan->ch_num)); + + return 0; + +err_wrong_chan: + edma_free_channel(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); + struct device *dev = chan->device->dev; + int i; + + /* Terminate transfers */ + edma_stop(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->slot[i]); + echan->slot[i] = -1; + } + } + + /* Free EDMA channel */ + if (echan->alloced) { + edma_free_channel(echan->ch_num); + echan->alloced = false; + } + + dev_info(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 size_t edma_desc_size(struct edma_desc *edesc) +{ + int i; + size_t size; + + if (edesc->absync) + for (size = i = 0; i < edesc->pset_nr; i++) + size += (edesc->pset[i].a_b_cnt & 0xffff) * + (edesc->pset[i].a_b_cnt >> 16) * + edesc->pset[i].ccnt; + else + size = (edesc->pset[0].a_b_cnt & 0xffff) * + (edesc->pset[0].a_b_cnt >> 16) + + (edesc->pset[0].a_b_cnt & 0xffff) * + (SZ_64K - 1) * edesc->pset[0].ccnt; + + return size; +} + +/* 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_SUCCESS || !txstate) + return ret; + + spin_lock_irqsave(&echan->vchan.lock, flags); + vdesc = vchan_find_desc(&echan->vchan, cookie); + if (vdesc) { + txstate->residue = edma_desc_size(to_edma_desc(&vdesc->tx)); + } else if (echan->edesc && echan->edesc->vdesc.tx.cookie == cookie) { + struct edma_desc *edesc = echan->edesc; + txstate->residue = edma_desc_size(edesc); + } else { + txstate->residue = 0; + } + 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 < EDMA_CHANS; i++) { + struct edma_chan *echan = &echans[i]; + echan->ch_num = EDMA_CTLR_CHAN(ecc->ctlr, 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; + } +} + +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_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_control = edma_control; + dma->dev = dev; + + INIT_LIST_HEAD(&dma->channels); +} + +static int __devinit edma_probe(struct platform_device *pdev) +{ + struct edma_cc *ecc; + int ret; + + ecc = devm_kzalloc(&pdev->dev, sizeof(*ecc), GFP_KERNEL); + if (!ecc) { + dev_err(&pdev->dev, "Can't allocate controller\n"); + return -ENOMEM; + } + + ecc->ctlr = pdev->id; + ecc->dummy_slot = edma_alloc_slot(ecc->ctlr, EDMA_SLOT_ANY); + if (ecc->dummy_slot < 0) { + dev_err(&pdev->dev, "Can't allocate PaRAM dummy slot\n"); + return -EIO; + } + + dma_cap_zero(ecc->dma_slave.cap_mask); + dma_cap_set(DMA_SLAVE, ecc->dma_slave.cap_mask); + + edma_dma_init(ecc, &ecc->dma_slave, &pdev->dev); + + edma_chan_init(ecc, &ecc->dma_slave, ecc->slave_chans); + + ret = dma_async_device_register(&ecc->dma_slave); + if (ret) + goto err_reg1; + + platform_set_drvdata(pdev, ecc); + + dev_info(&pdev->dev, "TI EDMA DMA engine driver\n"); + + return 0; + +err_reg1: + edma_free_slot(ecc->dummy_slot); + return ret; +} + +static int __devexit edma_remove(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct edma_cc *ecc = dev_get_drvdata(dev); + + dma_async_device_unregister(&ecc->dma_slave); + edma_free_slot(ecc->dummy_slot); + + return 0; +} + +static struct platform_driver edma_driver = { + .probe = edma_probe, + .remove = __devexit_p(edma_remove), + .driver = { + .name = "edma-dma-engine", + .owner = THIS_MODULE, + }, +}; + +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 struct platform_device *pdev0, *pdev1; + +static const struct platform_device_info edma_dev_info0 = { + .name = "edma-dma-engine", + .id = 0, + .dma_mask = DMA_BIT_MASK(32), +}; + +static const struct platform_device_info edma_dev_info1 = { + .name = "edma-dma-engine", + .id = 1, + .dma_mask = DMA_BIT_MASK(32), +}; + +static int edma_init(void) +{ + int ret = platform_driver_register(&edma_driver); + + if (ret == 0) { + pdev0 = platform_device_register_full(&edma_dev_info0); + if (IS_ERR(pdev0)) { + platform_driver_unregister(&edma_driver); + ret = PTR_ERR(pdev0); + goto out; + } + } + + if (EDMA_CTLRS == 2) { + pdev1 = platform_device_register_full(&edma_dev_info1); + if (IS_ERR(pdev1)) { + platform_driver_unregister(&edma_driver); + platform_device_unregister(pdev0); + ret = PTR_ERR(pdev1); + } + } + +out: + return ret; +} +subsys_initcall(edma_init); + +static void __exit edma_exit(void) +{ + platform_device_unregister(pdev0); + if (pdev1) + platform_device_unregister(pdev1); + platform_driver_unregister(&edma_driver); +} +module_exit(edma_exit); + +MODULE_AUTHOR("Matt Porter <mporter@ti.com>"); +MODULE_DESCRIPTION("TI EDMA DMA engine driver"); +MODULE_LICENSE("GPL v2"); diff --git a/include/linux/edma.h b/include/linux/edma.h new file mode 100644 index 0000000..a1307e7 --- /dev/null +++ b/include/linux/edma.h @@ -0,0 +1,29 @@ +/* + * 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. + */ +#ifndef __LINUX_EDMA_H +#define __LINUX_EDMA_H + +struct dma_chan; + +#if defined(CONFIG_TI_EDMA) || defined(CONFIG_TI_EDMA_MODULE) +bool edma_filter_fn(struct dma_chan *, void *); +#else +static inline bool edma_filter_fn(struct dma_chan *chan, void *param) +{ + return false; +} +#endif + +#endif |