Add Slave and Cyclic mode support for Actions Semi Owl S900 SoC. The slave mode supports bus width of 4 bytes common for all peripherals and 1 byte specific for UART. The cyclic mode supports only block mode transfer. Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> --- drivers/dma/owl-dma.c | 273 ++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 266 insertions(+), 7 deletions(-) diff --git a/drivers/dma/owl-dma.c b/drivers/dma/owl-dma.c index 7812a6338acd..7f7b3e76bcf7 100644 --- a/drivers/dma/owl-dma.c +++ b/drivers/dma/owl-dma.c @@ -21,6 +21,7 @@ #include <linux/mm.h> #include <linux/module.h> #include <linux/of_device.h> +#include <linux/of_dma.h> #include <linux/slab.h> #include "virt-dma.h" @@ -165,6 +166,7 @@ struct owl_dma_lli { struct owl_dma_txd { struct virt_dma_desc vd; struct list_head lli_list; + bool cyclic; }; /** @@ -191,6 +193,8 @@ struct owl_dma_vchan { struct virt_dma_chan vc; struct owl_dma_pchan *pchan; struct owl_dma_txd *txd; + struct dma_slave_config cfg; + u8 drq; }; /** @@ -336,9 +340,11 @@ static struct owl_dma_lli *owl_dma_alloc_lli(struct owl_dma *od) static struct owl_dma_lli *owl_dma_add_lli(struct owl_dma_txd *txd, struct owl_dma_lli *prev, - struct owl_dma_lli *next) + struct owl_dma_lli *next, + bool is_cyclic) { - list_add_tail(&next->node, &txd->lli_list); + if (!is_cyclic) + list_add_tail(&next->node, &txd->lli_list); if (prev) { prev->hw.next_lli = next->phys; @@ -351,7 +357,9 @@ static struct owl_dma_lli *owl_dma_add_lli(struct owl_dma_txd *txd, static inline int owl_dma_cfg_lli(struct owl_dma_vchan *vchan, struct owl_dma_lli *lli, dma_addr_t src, dma_addr_t dst, - u32 len, enum dma_transfer_direction dir) + u32 len, enum dma_transfer_direction dir, + struct dma_slave_config *sconfig, + bool is_cyclic) { struct owl_dma_lli_hw *hw = &lli->hw; u32 mode; @@ -364,6 +372,26 @@ static inline int owl_dma_cfg_lli(struct owl_dma_vchan *vchan, OWL_DMA_MODE_DT_DCU | OWL_DMA_MODE_SAM_INC | OWL_DMA_MODE_DAM_INC; + break; + case DMA_MEM_TO_DEV: + mode |= OWL_DMA_MODE_TS(vchan->drq) + | OWL_DMA_MODE_ST_DCU | OWL_DMA_MODE_DT_DEV + | OWL_DMA_MODE_SAM_INC | OWL_DMA_MODE_DAM_CONST; + + /* Handle bus width for UART */ + if (sconfig->dst_addr_width == DMA_SLAVE_BUSWIDTH_1_BYTE) + mode |= OWL_DMA_MODE_NDDBW_8BIT; + + break; + case DMA_DEV_TO_MEM: + mode |= OWL_DMA_MODE_TS(vchan->drq) + | OWL_DMA_MODE_ST_DEV | OWL_DMA_MODE_DT_DCU + | OWL_DMA_MODE_SAM_CONST | OWL_DMA_MODE_DAM_INC; + + /* Handle bus width for UART */ + if (sconfig->src_addr_width == DMA_SLAVE_BUSWIDTH_1_BYTE) + mode |= OWL_DMA_MODE_NDDBW_8BIT; + break; default: return -EINVAL; @@ -381,7 +409,10 @@ static inline int owl_dma_cfg_lli(struct owl_dma_vchan *vchan, OWL_DMA_LLC_SAV_LOAD_NEXT | OWL_DMA_LLC_DAV_LOAD_NEXT); - hw->ctrlb = llc_hw_ctrlb(OWL_DMA_INTCTL_SUPER_BLOCK); + if (is_cyclic) + hw->ctrlb = llc_hw_ctrlb(OWL_DMA_INTCTL_BLOCK); + else + hw->ctrlb = llc_hw_ctrlb(OWL_DMA_INTCTL_SUPER_BLOCK); return 0; } @@ -443,6 +474,16 @@ static void owl_dma_terminate_pchan(struct owl_dma *od, spin_unlock_irqrestore(&od->lock, flags); } +static void owl_dma_pause_pchan(struct owl_dma_pchan *pchan) +{ + pchan_writel(pchan, 1, OWL_DMAX_PAUSE); +} + +static void owl_dma_resume_pchan(struct owl_dma_pchan *pchan) +{ + pchan_writel(pchan, 0, OWL_DMAX_PAUSE); +} + static int owl_dma_start_next_txd(struct owl_dma_vchan *vchan) { struct owl_dma *od = to_owl_dma(vchan->vc.chan.device); @@ -464,7 +505,10 @@ static int owl_dma_start_next_txd(struct owl_dma_vchan *vchan) lli = list_first_entry(&txd->lli_list, struct owl_dma_lli, node); - int_ctl = OWL_DMA_INTCTL_SUPER_BLOCK; + if (txd->cyclic) + int_ctl = OWL_DMA_INTCTL_BLOCK; + else + int_ctl = OWL_DMA_INTCTL_SUPER_BLOCK; pchan_writel(pchan, OWL_DMAX_MODE, OWL_DMA_MODE_LME); pchan_writel(pchan, OWL_DMAX_LINKLIST_CTL, @@ -627,6 +671,54 @@ static int owl_dma_terminate_all(struct dma_chan *chan) return 0; } +static int owl_dma_config(struct dma_chan *chan, + struct dma_slave_config *config) +{ + struct owl_dma_vchan *vchan = to_owl_vchan(chan); + + /* Reject definitely invalid configurations */ + if (config->src_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES || + config->dst_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES) + return -EINVAL; + + memcpy(&vchan->cfg, config, sizeof(struct dma_slave_config)); + + return 0; +} + +static int owl_dma_pause(struct dma_chan *chan) +{ + struct owl_dma_vchan *vchan = to_owl_vchan(chan); + unsigned long flags; + + spin_lock_irqsave(&vchan->vc.lock, flags); + + owl_dma_pause_pchan(vchan->pchan); + + spin_unlock_irqrestore(&vchan->vc.lock, flags); + + return 0; +} + +static int owl_dma_resume(struct dma_chan *chan) +{ + struct owl_dma_vchan *vchan = to_owl_vchan(chan); + unsigned long flags; + + if (!vchan->pchan && !vchan->txd) + return 0; + + dev_dbg(chan2dev(chan), "vchan %p: resume\n", &vchan->vc); + + spin_lock_irqsave(&vchan->vc.lock, flags); + + owl_dma_resume_pchan(vchan->pchan); + + spin_unlock_irqrestore(&vchan->vc.lock, flags); + + return 0; +} + static u32 owl_dma_getbytes_chan(struct owl_dma_vchan *vchan) { struct owl_dma_pchan *pchan; @@ -754,13 +846,14 @@ static struct dma_async_tx_descriptor bytes = min_t(size_t, (len - offset), OWL_DMA_FRAME_MAX_LENGTH); ret = owl_dma_cfg_lli(vchan, lli, src + offset, dst + offset, - bytes, DMA_MEM_TO_MEM); + bytes, DMA_MEM_TO_MEM, + &vchan->cfg, txd->cyclic); if (ret) { dev_warn(chan2dev(chan), "failed to config lli\n"); goto err_txd_free; } - prev = owl_dma_add_lli(txd, prev, lli); + prev = owl_dma_add_lli(txd, prev, lli, false); } return vchan_tx_prep(&vchan->vc, &txd->vd, flags); @@ -770,6 +863,133 @@ static struct dma_async_tx_descriptor return NULL; } +static struct dma_async_tx_descriptor + *owl_dma_prep_slave_sg(struct dma_chan *chan, + struct scatterlist *sgl, + unsigned int sg_len, + enum dma_transfer_direction dir, + unsigned long flags, void *context) +{ + struct owl_dma *od = to_owl_dma(chan->device); + struct owl_dma_vchan *vchan = to_owl_vchan(chan); + struct dma_slave_config *sconfig = &vchan->cfg; + struct owl_dma_txd *txd; + struct owl_dma_lli *lli, *prev = NULL; + struct scatterlist *sg; + dma_addr_t addr, src = 0, dst = 0; + size_t len; + int ret, i; + + txd = kzalloc(sizeof(*txd), GFP_NOWAIT); + if (!txd) + return NULL; + + INIT_LIST_HEAD(&txd->lli_list); + + for_each_sg(sgl, sg, sg_len, i) { + addr = sg_dma_address(sg); + len = sg_dma_len(sg); + + if (len > OWL_DMA_FRAME_MAX_LENGTH) { + dev_err(od->dma.dev, + "frame length exceeds max supported length"); + goto err_txd_free; + } + + lli = owl_dma_alloc_lli(od); + if (!lli) { + dev_err(chan2dev(chan), "failed to allocate lli"); + goto err_txd_free; + } + + if (dir == DMA_MEM_TO_DEV) { + src = addr; + dst = sconfig->dst_addr; + } else { + src = sconfig->src_addr; + dst = addr; + } + + ret = owl_dma_cfg_lli(vchan, lli, src, dst, len, dir, sconfig, + txd->cyclic); + if (ret) { + dev_warn(chan2dev(chan), "failed to config lli"); + goto err_txd_free; + } + + prev = owl_dma_add_lli(txd, prev, lli, false); + } + + return vchan_tx_prep(&vchan->vc, &txd->vd, flags); + +err_txd_free: + owl_dma_free_txd(od, txd); + + return NULL; +} + +static struct dma_async_tx_descriptor + *owl_prep_dma_cyclic(struct dma_chan *chan, + dma_addr_t buf_addr, size_t buf_len, + size_t period_len, + enum dma_transfer_direction dir, + unsigned long flags) +{ + struct owl_dma *od = to_owl_dma(chan->device); + struct owl_dma_vchan *vchan = to_owl_vchan(chan); + struct dma_slave_config *sconfig = &vchan->cfg; + struct owl_dma_txd *txd; + struct owl_dma_lli *lli, *prev = NULL, *first = NULL; + dma_addr_t src = 0, dst = 0; + unsigned int periods = buf_len / period_len; + int ret, i; + + txd = kzalloc(sizeof(*txd), GFP_NOWAIT); + if (!txd) + return NULL; + + INIT_LIST_HEAD(&txd->lli_list); + txd->cyclic = true; + + for (i = 0; i < periods; i++) { + lli = owl_dma_alloc_lli(od); + if (!lli) { + dev_warn(chan2dev(chan), "failed to allocate lli"); + goto err_txd_free; + } + + if (dir == DMA_MEM_TO_DEV) { + src = buf_addr + (period_len * i); + dst = sconfig->dst_addr; + } else if (dir == DMA_DEV_TO_MEM) { + src = sconfig->src_addr; + dst = buf_addr + (period_len * i); + } + + ret = owl_dma_cfg_lli(vchan, lli, src, dst, period_len, + dir, sconfig, txd->cyclic); + if (ret) { + dev_warn(chan2dev(chan), "failed to config lli"); + goto err_txd_free; + } + + if (!first) + first = lli; + + prev = owl_dma_add_lli(txd, prev, lli, false); + } + + /* close the cyclic list */ + owl_dma_add_lli(txd, prev, first, true); + + return vchan_tx_prep(&vchan->vc, &txd->vd, flags); + +err_txd_free: + owl_dma_free_txd(od, txd); + + return NULL; +} + static void owl_dma_free_chan_resources(struct dma_chan *chan) { struct owl_dma_vchan *vchan = to_owl_vchan(chan); @@ -790,6 +1010,27 @@ static inline void owl_dma_free(struct owl_dma *od) } } +static struct dma_chan *owl_dma_of_xlate(struct of_phandle_args *dma_spec, + struct of_dma *ofdma) +{ + struct owl_dma *od = ofdma->of_dma_data; + struct owl_dma_vchan *vchan; + struct dma_chan *chan; + u8 drq = dma_spec->args[0]; + + if (drq > od->nr_vchans) + return NULL; + + chan = dma_get_any_slave_channel(&od->dma); + if (!chan) + return NULL; + + vchan = to_owl_vchan(chan); + vchan->drq = drq; + + return chan; +} + static int owl_dma_probe(struct platform_device *pdev) { struct device_node *np = pdev->dev.of_node; @@ -833,12 +1074,19 @@ static int owl_dma_probe(struct platform_device *pdev) spin_lock_init(&od->lock); dma_cap_set(DMA_MEMCPY, od->dma.cap_mask); + dma_cap_set(DMA_SLAVE, od->dma.cap_mask); + dma_cap_set(DMA_CYCLIC, od->dma.cap_mask); od->dma.dev = &pdev->dev; od->dma.device_free_chan_resources = owl_dma_free_chan_resources; od->dma.device_tx_status = owl_dma_tx_status; od->dma.device_issue_pending = owl_dma_issue_pending; od->dma.device_prep_dma_memcpy = owl_dma_prep_memcpy; + od->dma.device_prep_slave_sg = owl_dma_prep_slave_sg; + od->dma.device_prep_dma_cyclic = owl_prep_dma_cyclic; + od->dma.device_config = owl_dma_config; + od->dma.device_pause = owl_dma_pause; + od->dma.device_resume = owl_dma_resume; od->dma.device_terminate_all = owl_dma_terminate_all; od->dma.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES); od->dma.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_4_BYTES); @@ -910,8 +1158,18 @@ static int owl_dma_probe(struct platform_device *pdev) goto err_pool_free; } + /* Device-tree DMA controller registration */ + ret = of_dma_controller_register(pdev->dev.of_node, + owl_dma_of_xlate, od); + if (ret) { + dev_err(&pdev->dev, "of_dma_controller_register failed\n"); + goto err_dma_unregister; + } + return 0; +err_dma_unregister: + dma_async_device_unregister(&od->dma); err_pool_free: clk_disable_unprepare(od->clk); dma_pool_destroy(od->lli_pool); @@ -923,6 +1181,7 @@ static int owl_dma_remove(struct platform_device *pdev) { struct owl_dma *od = platform_get_drvdata(pdev); + of_dma_controller_free(pdev->dev.of_node); dma_async_device_unregister(&od->dma); /* Mask all interrupts for this execution environment */ -- 2.17.1