--- zzzz-none-000/linux-3.10.107/drivers/dma/mpc512x_dma.c 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/drivers/dma/mpc512x_dma.c 2021-02-04 17:41:59.000000000 +0000 @@ -2,6 +2,7 @@ * Copyright (C) Freescale Semicondutor, Inc. 2007, 2008. * Copyright (C) Semihalf 2009 * Copyright (C) Ilya Yanok, Emcraft Systems 2010 + * Copyright (C) Alexander Popov, Promcontroller 2014 * * Written by Piotr Ziecik . Hardware description * (defines, structures and comments) was taken from MPC5121 DMA driver @@ -20,17 +21,23 @@ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. * - * 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., 59 - * Temple Place - Suite 330, Boston, MA 02111-1307, USA. - * * The full GNU General Public License is included in this distribution in the * file called COPYING. */ /* - * This is initial version of MPC5121 DMA driver. Only memory to memory - * transfers are supported (tested using dmatest module). + * MPC512x and MPC8308 DMA driver. It supports + * memory to memory data transfers (tested using dmatest module) and + * data transfers between memory and peripheral I/O memory + * by means of slave scatter/gather with these limitations: + * - chunked transfers (described by s/g lists with more than one item) + * are refused as long as proper support for scatter/gather is missing; + * - transfers on MPC8308 always start from software as this SoC appears + * not to have external request lines for peripheral flow control; + * - only peripheral devices with 4-byte FIFO access register are supported; + * - minimal memory <-> I/O memory transfer chunk is 4 bytes and consequently + * source and destination addresses must be 4-byte aligned + * and transfer size must be aligned on (4 * maxburst) boundary; */ #include @@ -39,7 +46,10 @@ #include #include #include +#include #include +#include +#include #include #include @@ -50,9 +60,17 @@ #define MPC_DMA_DESCRIPTORS 64 /* Macro definitions */ -#define MPC_DMA_CHANNELS 64 #define MPC_DMA_TCD_OFFSET 0x1000 +/* + * Maximum channel counts for individual hardware variants + * and the maximum channel count over all supported controllers, + * used for data structure size + */ +#define MPC8308_DMACHAN_MAX 16 +#define MPC512x_DMACHAN_MAX 64 +#define MPC_DMA_CHANNELS 64 + /* Arbitration mode of group and channel */ #define MPC_DMA_DMACR_EDCG (1 << 31) #define MPC_DMA_DMACR_ERGA (1 << 3) @@ -179,6 +197,7 @@ dma_addr_t tcd_paddr; int error; struct list_head node; + int will_access_peripheral; }; struct mpc_dma_chan { @@ -191,6 +210,12 @@ struct mpc_dma_tcd *tcd; dma_addr_t tcd_paddr; + /* Settings for access to peripheral FIFO */ + dma_addr_t src_per_paddr; + u32 src_tcd_nunits; + dma_addr_t dst_per_paddr; + u32 dst_tcd_nunits; + /* Lock for this structure */ spinlock_t lock; }; @@ -241,8 +266,23 @@ struct mpc_dma_desc *mdesc; int cid = mchan->chan.chan_id; - /* Move all queued descriptors to active list */ - list_splice_tail_init(&mchan->queued, &mchan->active); + while (!list_empty(&mchan->queued)) { + mdesc = list_first_entry(&mchan->queued, + struct mpc_dma_desc, node); + /* + * Grab either several mem-to-mem transfer descriptors + * or one peripheral transfer descriptor, + * don't mix mem-to-mem and peripheral transfer descriptors + * within the same 'active' list. + */ + if (mdesc->will_access_peripheral) { + if (list_empty(&mchan->active)) + list_move_tail(&mdesc->node, &mchan->active); + break; + } else { + list_move_tail(&mdesc->node, &mchan->active); + } + } /* Chain descriptors into one transaction */ list_for_each_entry(mdesc, &mchan->active, node) { @@ -268,7 +308,17 @@ if (first != prev) mdma->tcd[cid].e_sg = 1; - out_8(&mdma->regs->dmassrt, cid); + + if (mdma->is_mpc8308) { + /* MPC8308, no request lines, software initiated start */ + out_8(&mdma->regs->dmassrt, cid); + } else if (first->will_access_peripheral) { + /* Peripherals involved, start by external request signal */ + out_8(&mdma->regs->dmaserq, cid); + } else { + /* Memory to memory transfer, software initiated start */ + out_8(&mdma->regs->dmassrt, cid); + } } /* Handle interrupt on one half of DMA controller (32 channels) */ @@ -556,15 +606,7 @@ mpc_dma_tx_status(struct dma_chan *chan, dma_cookie_t cookie, struct dma_tx_state *txstate) { - struct mpc_dma_chan *mchan = dma_chan_to_mpc_dma_chan(chan); - enum dma_status ret; - unsigned long flags; - - spin_lock_irqsave(&mchan->lock, flags); - ret = dma_cookie_status(chan, cookie, txstate); - spin_unlock_irqrestore(&mchan->lock, flags); - - return ret; + return dma_cookie_status(chan, cookie, txstate); } /* Prepare descriptor for memory to memory copy */ @@ -594,6 +636,7 @@ } mdesc->error = 0; + mdesc->will_access_peripheral = 0; tcd = mdesc->tcd; /* Prepare Transfer Control Descriptor for this transaction */ @@ -641,6 +684,183 @@ return &mdesc->desc; } +static struct dma_async_tx_descriptor * +mpc_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 mpc_dma *mdma = dma_chan_to_mpc_dma(chan); + struct mpc_dma_chan *mchan = dma_chan_to_mpc_dma_chan(chan); + struct mpc_dma_desc *mdesc = NULL; + dma_addr_t per_paddr; + u32 tcd_nunits; + struct mpc_dma_tcd *tcd; + unsigned long iflags; + struct scatterlist *sg; + size_t len; + int iter, i; + + /* Currently there is no proper support for scatter/gather */ + if (sg_len != 1) + return NULL; + + if (!is_slave_direction(direction)) + return NULL; + + for_each_sg(sgl, sg, sg_len, i) { + spin_lock_irqsave(&mchan->lock, iflags); + + mdesc = list_first_entry(&mchan->free, + struct mpc_dma_desc, node); + if (!mdesc) { + spin_unlock_irqrestore(&mchan->lock, iflags); + /* Try to free completed descriptors */ + mpc_dma_process_completed(mdma); + return NULL; + } + + list_del(&mdesc->node); + + if (direction == DMA_DEV_TO_MEM) { + per_paddr = mchan->src_per_paddr; + tcd_nunits = mchan->src_tcd_nunits; + } else { + per_paddr = mchan->dst_per_paddr; + tcd_nunits = mchan->dst_tcd_nunits; + } + + spin_unlock_irqrestore(&mchan->lock, iflags); + + if (per_paddr == 0 || tcd_nunits == 0) + goto err_prep; + + mdesc->error = 0; + mdesc->will_access_peripheral = 1; + + /* Prepare Transfer Control Descriptor for this transaction */ + tcd = mdesc->tcd; + + memset(tcd, 0, sizeof(struct mpc_dma_tcd)); + + if (!IS_ALIGNED(sg_dma_address(sg), 4)) + goto err_prep; + + if (direction == DMA_DEV_TO_MEM) { + tcd->saddr = per_paddr; + tcd->daddr = sg_dma_address(sg); + tcd->soff = 0; + tcd->doff = 4; + } else { + tcd->saddr = sg_dma_address(sg); + tcd->daddr = per_paddr; + tcd->soff = 4; + tcd->doff = 0; + } + + tcd->ssize = MPC_DMA_TSIZE_4; + tcd->dsize = MPC_DMA_TSIZE_4; + + len = sg_dma_len(sg); + tcd->nbytes = tcd_nunits * 4; + if (!IS_ALIGNED(len, tcd->nbytes)) + goto err_prep; + + iter = len / tcd->nbytes; + if (iter >= 1 << 15) { + /* len is too big */ + goto err_prep; + } + /* citer_linkch contains the high bits of iter */ + tcd->biter = iter & 0x1ff; + tcd->biter_linkch = iter >> 9; + tcd->citer = tcd->biter; + tcd->citer_linkch = tcd->biter_linkch; + + tcd->e_sg = 0; + tcd->d_req = 1; + + /* Place descriptor in prepared list */ + spin_lock_irqsave(&mchan->lock, iflags); + list_add_tail(&mdesc->node, &mchan->prepared); + spin_unlock_irqrestore(&mchan->lock, iflags); + } + + return &mdesc->desc; + +err_prep: + /* Put the descriptor back */ + spin_lock_irqsave(&mchan->lock, iflags); + list_add_tail(&mdesc->node, &mchan->free); + spin_unlock_irqrestore(&mchan->lock, iflags); + + return NULL; +} + +static int mpc_dma_device_config(struct dma_chan *chan, + struct dma_slave_config *cfg) +{ + struct mpc_dma_chan *mchan = dma_chan_to_mpc_dma_chan(chan); + unsigned long flags; + + /* + * Software constraints: + * - only transfers between a peripheral device and + * memory are supported; + * - only peripheral devices with 4-byte FIFO access register + * are supported; + * - minimal transfer chunk is 4 bytes and consequently + * source and destination addresses must be 4-byte aligned + * and transfer size must be aligned on (4 * maxburst) + * boundary; + * - during the transfer RAM address is being incremented by + * the size of minimal transfer chunk; + * - peripheral port's address is constant during the transfer. + */ + + if (cfg->src_addr_width != DMA_SLAVE_BUSWIDTH_4_BYTES || + cfg->dst_addr_width != DMA_SLAVE_BUSWIDTH_4_BYTES || + !IS_ALIGNED(cfg->src_addr, 4) || + !IS_ALIGNED(cfg->dst_addr, 4)) { + return -EINVAL; + } + + spin_lock_irqsave(&mchan->lock, flags); + + mchan->src_per_paddr = cfg->src_addr; + mchan->src_tcd_nunits = cfg->src_maxburst; + mchan->dst_per_paddr = cfg->dst_addr; + mchan->dst_tcd_nunits = cfg->dst_maxburst; + + /* Apply defaults */ + if (mchan->src_tcd_nunits == 0) + mchan->src_tcd_nunits = 1; + if (mchan->dst_tcd_nunits == 0) + mchan->dst_tcd_nunits = 1; + + spin_unlock_irqrestore(&mchan->lock, flags); + + return 0; +} + +static int mpc_dma_device_terminate_all(struct dma_chan *chan) +{ + struct mpc_dma_chan *mchan = dma_chan_to_mpc_dma_chan(chan); + struct mpc_dma *mdma = dma_chan_to_mpc_dma(chan); + unsigned long flags; + + /* Disable channel requests */ + spin_lock_irqsave(&mchan->lock, flags); + + out_8(&mdma->regs->dmacerq, chan->chan_id); + list_splice_tail_init(&mchan->prepared, &mchan->free); + list_splice_tail_init(&mchan->queued, &mchan->free); + list_splice_tail_init(&mchan->active, &mchan->free); + + spin_unlock_irqrestore(&mchan->lock, flags); + + return 0; +} + static int mpc_dma_probe(struct platform_device *op) { struct device_node *dn = op->dev.of_node; @@ -651,17 +871,20 @@ struct resource res; ulong regs_start, regs_size; int retval, i; + u8 chancnt; mdma = devm_kzalloc(dev, sizeof(struct mpc_dma), GFP_KERNEL); if (!mdma) { dev_err(dev, "Memory exhausted!\n"); - return -ENOMEM; + retval = -ENOMEM; + goto err; } mdma->irq = irq_of_parse_and_map(dn, 0); if (mdma->irq == NO_IRQ) { dev_err(dev, "Error mapping IRQ!\n"); - return -EINVAL; + retval = -EINVAL; + goto err; } if (of_device_is_compatible(dn, "fsl,mpc8308-dma")) { @@ -669,14 +892,15 @@ mdma->irq2 = irq_of_parse_and_map(dn, 1); if (mdma->irq2 == NO_IRQ) { dev_err(dev, "Error mapping IRQ!\n"); - return -EINVAL; + retval = -EINVAL; + goto err_dispose1; } } retval = of_address_to_resource(dn, 0, &res); if (retval) { dev_err(dev, "Error parsing memory region!\n"); - return retval; + goto err_dispose2; } regs_start = res.start; @@ -684,31 +908,34 @@ if (!devm_request_mem_region(dev, regs_start, regs_size, DRV_NAME)) { dev_err(dev, "Error requesting memory region!\n"); - return -EBUSY; + retval = -EBUSY; + goto err_dispose2; } mdma->regs = devm_ioremap(dev, regs_start, regs_size); if (!mdma->regs) { dev_err(dev, "Error mapping memory region!\n"); - return -ENOMEM; + retval = -ENOMEM; + goto err_dispose2; } mdma->tcd = (struct mpc_dma_tcd *)((u8 *)(mdma->regs) + MPC_DMA_TCD_OFFSET); - retval = devm_request_irq(dev, mdma->irq, &mpc_dma_irq, 0, DRV_NAME, - mdma); + retval = request_irq(mdma->irq, &mpc_dma_irq, 0, DRV_NAME, mdma); if (retval) { dev_err(dev, "Error requesting IRQ!\n"); - return -EINVAL; + retval = -EINVAL; + goto err_dispose2; } if (mdma->is_mpc8308) { - retval = devm_request_irq(dev, mdma->irq2, &mpc_dma_irq, 0, - DRV_NAME, mdma); + retval = request_irq(mdma->irq2, &mpc_dma_irq, 0, + DRV_NAME, mdma); if (retval) { dev_err(dev, "Error requesting IRQ2!\n"); - return -EINVAL; + retval = -EINVAL; + goto err_free1; } } @@ -716,20 +943,25 @@ dma = &mdma->dma; dma->dev = dev; - if (!mdma->is_mpc8308) - dma->chancnt = MPC_DMA_CHANNELS; - else - dma->chancnt = 16; /* MPC8308 DMA has only 16 channels */ dma->device_alloc_chan_resources = mpc_dma_alloc_chan_resources; dma->device_free_chan_resources = mpc_dma_free_chan_resources; dma->device_issue_pending = mpc_dma_issue_pending; dma->device_tx_status = mpc_dma_tx_status; dma->device_prep_dma_memcpy = mpc_dma_prep_memcpy; + dma->device_prep_slave_sg = mpc_dma_prep_slave_sg; + dma->device_config = mpc_dma_device_config; + dma->device_terminate_all = mpc_dma_device_terminate_all; INIT_LIST_HEAD(&dma->channels); dma_cap_set(DMA_MEMCPY, dma->cap_mask); + dma_cap_set(DMA_SLAVE, dma->cap_mask); + + if (mdma->is_mpc8308) + chancnt = MPC8308_DMACHAN_MAX; + else + chancnt = MPC512x_DMACHAN_MAX; - for (i = 0; i < dma->chancnt; i++) { + for (i = 0; i < chancnt; i++) { mchan = &mdma->channels[i]; mchan->chan.device = dma; @@ -753,7 +985,19 @@ * - Round-robin group arbitration, * - Round-robin channel arbitration. */ - if (!mdma->is_mpc8308) { + if (mdma->is_mpc8308) { + /* MPC8308 has 16 channels and lacks some registers */ + out_be32(&mdma->regs->dmacr, MPC_DMA_DMACR_ERCA); + + /* enable snooping */ + out_be32(&mdma->regs->dmagpor, MPC_DMA_DMAGPOR_SNOOP_ENABLE); + /* Disable error interrupts */ + out_be32(&mdma->regs->dmaeeil, 0); + + /* Clear interrupts status */ + out_be32(&mdma->regs->dmaintl, 0xFFFF); + out_be32(&mdma->regs->dmaerrl, 0xFFFF); + } else { out_be32(&mdma->regs->dmacr, MPC_DMA_DMACR_EDCG | MPC_DMA_DMACR_ERGA | MPC_DMA_DMACR_ERCA); @@ -774,28 +1018,35 @@ /* Route interrupts to IPIC */ out_be32(&mdma->regs->dmaihsa, 0); out_be32(&mdma->regs->dmailsa, 0); - } else { - /* MPC8308 has 16 channels and lacks some registers */ - out_be32(&mdma->regs->dmacr, MPC_DMA_DMACR_ERCA); - - /* enable snooping */ - out_be32(&mdma->regs->dmagpor, MPC_DMA_DMAGPOR_SNOOP_ENABLE); - /* Disable error interrupts */ - out_be32(&mdma->regs->dmaeeil, 0); - - /* Clear interrupts status */ - out_be32(&mdma->regs->dmaintl, 0xFFFF); - out_be32(&mdma->regs->dmaerrl, 0xFFFF); } /* Register DMA engine */ dev_set_drvdata(dev, mdma); retval = dma_async_device_register(dma); - if (retval) { - devm_free_irq(dev, mdma->irq, mdma); - irq_dispose_mapping(mdma->irq); + if (retval) + goto err_free2; + + /* Register with OF helpers for DMA lookups (nonfatal) */ + if (dev->of_node) { + retval = of_dma_controller_register(dev->of_node, + of_dma_xlate_by_chan_id, mdma); + if (retval) + dev_warn(dev, "Could not register for OF lookup\n"); } + return 0; + +err_free2: + if (mdma->is_mpc8308) + free_irq(mdma->irq2, mdma); +err_free1: + free_irq(mdma->irq, mdma); +err_dispose2: + if (mdma->is_mpc8308) + irq_dispose_mapping(mdma->irq2); +err_dispose1: + irq_dispose_mapping(mdma->irq); +err: return retval; } @@ -804,24 +1055,31 @@ struct device *dev = &op->dev; struct mpc_dma *mdma = dev_get_drvdata(dev); + if (dev->of_node) + of_dma_controller_free(dev->of_node); dma_async_device_unregister(&mdma->dma); - devm_free_irq(dev, mdma->irq, mdma); + if (mdma->is_mpc8308) { + free_irq(mdma->irq2, mdma); + irq_dispose_mapping(mdma->irq2); + } + free_irq(mdma->irq, mdma); irq_dispose_mapping(mdma->irq); return 0; } -static struct of_device_id mpc_dma_match[] = { +static const struct of_device_id mpc_dma_match[] = { { .compatible = "fsl,mpc5121-dma", }, + { .compatible = "fsl,mpc8308-dma", }, {}, }; +MODULE_DEVICE_TABLE(of, mpc_dma_match); static struct platform_driver mpc_dma_driver = { .probe = mpc_dma_probe, .remove = mpc_dma_remove, .driver = { .name = DRV_NAME, - .owner = THIS_MODULE, .of_match_table = mpc_dma_match, }, };