diff options
Diffstat (limited to 'drivers/dma/at_hdmac.c')
| -rw-r--r-- | drivers/dma/at_hdmac.c | 211 |
1 files changed, 149 insertions, 62 deletions
diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c index e923cda930f9..c787f38a186a 100644 --- a/drivers/dma/at_hdmac.c +++ b/drivers/dma/at_hdmac.c @@ -14,6 +14,7 @@ * found on AT91SAM9263. */ +#include <dt-bindings/dma/at91.h> #include <linux/clk.h> #include <linux/dmaengine.h> #include <linux/dma-mapping.h> @@ -54,6 +55,7 @@ MODULE_PARM_DESC(init_nr_desc_per_channel, /* prototypes */ static dma_cookie_t atc_tx_submit(struct dma_async_tx_descriptor *tx); +static void atc_issue_pending(struct dma_chan *chan); /*----------------------------------------------------------------------*/ @@ -230,6 +232,95 @@ static void atc_dostart(struct at_dma_chan *atchan, struct at_desc *first) vdbg_dump_regs(atchan); } +/* + * atc_get_current_descriptors - + * locate the descriptor which equal to physical address in DSCR + * @atchan: the channel we want to start + * @dscr_addr: physical descriptor address in DSCR + */ +static struct at_desc *atc_get_current_descriptors(struct at_dma_chan *atchan, + u32 dscr_addr) +{ + struct at_desc *desc, *_desc, *child, *desc_cur = NULL; + + list_for_each_entry_safe(desc, _desc, &atchan->active_list, desc_node) { + if (desc->lli.dscr == dscr_addr) { + desc_cur = desc; + break; + } + + list_for_each_entry(child, &desc->tx_list, desc_node) { + if (child->lli.dscr == dscr_addr) { + desc_cur = child; + break; + } + } + } + + return desc_cur; +} + +/* + * atc_get_bytes_left - + * Get the number of bytes residue in dma buffer, + * @chan: the channel we want to start + */ +static int atc_get_bytes_left(struct dma_chan *chan) +{ + struct at_dma_chan *atchan = to_at_dma_chan(chan); + struct at_dma *atdma = to_at_dma(chan->device); + int chan_id = atchan->chan_common.chan_id; + struct at_desc *desc_first = atc_first_active(atchan); + struct at_desc *desc_cur; + int ret = 0, count = 0; + + /* + * Initialize necessary values in the first time. + * remain_desc record remain desc length. + */ + if (atchan->remain_desc == 0) + /* First descriptor embedds the transaction length */ + atchan->remain_desc = desc_first->len; + + /* + * This happens when current descriptor transfer complete. + * The residual buffer size should reduce current descriptor length. + */ + if (unlikely(test_bit(ATC_IS_BTC, &atchan->status))) { + clear_bit(ATC_IS_BTC, &atchan->status); + desc_cur = atc_get_current_descriptors(atchan, + channel_readl(atchan, DSCR)); + if (!desc_cur) { + ret = -EINVAL; + goto out; + } + atchan->remain_desc -= (desc_cur->lli.ctrla & ATC_BTSIZE_MAX) + << (desc_first->tx_width); + if (atchan->remain_desc < 0) { + ret = -EINVAL; + goto out; + } else { + ret = atchan->remain_desc; + } + } else { + /* + * Get residual bytes when current + * descriptor transfer in progress. + */ + count = (channel_readl(atchan, CTRLA) & ATC_BTSIZE_MAX) + << (desc_first->tx_width); + ret = atchan->remain_desc - count; + } + /* + * Check fifo empty. + */ + if (!(dma_readl(atdma, CHSR) & AT_DMA_EMPT(chan_id))) + atc_issue_pending(chan); + +out: + return ret; +} + /** * atc_chain_complete - finish work for one transaction chain * @atchan: channel we work on @@ -327,37 +418,6 @@ static void atc_complete_all(struct at_dma_chan *atchan) } /** - * atc_cleanup_descriptors - cleanup up finished descriptors in active_list - * @atchan: channel to be cleaned up - * - * Called with atchan->lock held and bh disabled - */ -static void atc_cleanup_descriptors(struct at_dma_chan *atchan) -{ - struct at_desc *desc, *_desc; - struct at_desc *child; - - dev_vdbg(chan2dev(&atchan->chan_common), "cleanup descriptors\n"); - - list_for_each_entry_safe(desc, _desc, &atchan->active_list, desc_node) { - if (!(desc->lli.ctrla & ATC_DONE)) - /* This one is currently in progress */ - return; - - list_for_each_entry(child, &desc->tx_list, desc_node) - if (!(child->lli.ctrla & ATC_DONE)) - /* Currently in progress */ - return; - - /* - * No descriptors so far seem to be in progress, i.e. - * this chain must be done. - */ - atc_chain_complete(atchan, desc); - } -} - -/** * atc_advance_work - at the end of a transaction, move forward * @atchan: channel where the transaction ended * @@ -496,6 +556,8 @@ static irqreturn_t at_dma_interrupt(int irq, void *dev_id) /* Give information to tasklet */ set_bit(ATC_IS_ERROR, &atchan->status); } + if (pending & AT_DMA_BTC(i)) + set_bit(ATC_IS_BTC, &atchan->status); tasklet_schedule(&atchan->tasklet); ret = IRQ_HANDLED; } @@ -615,6 +677,7 @@ atc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, /* First descriptor of the chain embedds additional information */ first->txd.cookie = -EBUSY; first->len = len; + first->tx_width = src_width; /* set end-of-link to the last link descriptor of list*/ set_desc_eol(desc); @@ -761,6 +824,7 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, /* First descriptor of the chain embedds additional information */ first->txd.cookie = -EBUSY; first->len = total_len; + first->tx_width = reg_width; /* first link descriptor of list is responsible of flags */ first->txd.flags = flags; /* client is in control of this ack */ @@ -919,6 +983,7 @@ atc_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len, /* First descriptor of the chain embedds additional information */ first->txd.cookie = -EBUSY; first->len = buf_len; + first->tx_width = reg_width; return &first->txd; @@ -1032,34 +1097,36 @@ atc_tx_status(struct dma_chan *chan, struct dma_tx_state *txstate) { struct at_dma_chan *atchan = to_at_dma_chan(chan); - dma_cookie_t last_used; - dma_cookie_t last_complete; unsigned long flags; enum dma_status ret; - - spin_lock_irqsave(&atchan->lock, flags); + int bytes = 0; ret = dma_cookie_status(chan, cookie, txstate); - if (ret != DMA_SUCCESS) { - atc_cleanup_descriptors(atchan); + if (ret == DMA_SUCCESS) + return ret; + /* + * There's no point calculating the residue if there's + * no txstate to store the value. + */ + if (!txstate) + return DMA_ERROR; - ret = dma_cookie_status(chan, cookie, txstate); - } + spin_lock_irqsave(&atchan->lock, flags); - last_complete = chan->completed_cookie; - last_used = chan->cookie; + /* Get number of bytes left in the active transactions */ + bytes = atc_get_bytes_left(chan); spin_unlock_irqrestore(&atchan->lock, flags); - if (ret != DMA_SUCCESS) - dma_set_residue(txstate, atc_first_active(atchan)->len); - - if (atc_chan_is_paused(atchan)) - ret = DMA_PAUSED; + if (unlikely(bytes < 0)) { + dev_vdbg(chan2dev(chan), "get residual bytes error\n"); + return DMA_ERROR; + } else { + dma_set_residue(txstate, bytes); + } - dev_vdbg(chan2dev(chan), "tx_status %d: cookie = %d (d%d, u%d)\n", - ret, cookie, last_complete ? last_complete : 0, - last_used ? last_used : 0); + dev_vdbg(chan2dev(chan), "tx_status %d: cookie = %d residue = %d\n", + ret, cookie, bytes); return ret; } @@ -1120,7 +1187,7 @@ static int atc_alloc_chan_resources(struct dma_chan *chan) */ BUG_ON(!atslave->dma_dev || atslave->dma_dev != atdma->dma_common.dev); - /* if cfg configuration specified take it instad of default */ + /* if cfg configuration specified take it instead of default */ if (atslave->cfg) cfg = atslave->cfg; } @@ -1143,6 +1210,7 @@ static int atc_alloc_chan_resources(struct dma_chan *chan) spin_lock_irqsave(&atchan->lock, flags); atchan->descs_allocated = i; + atchan->remain_desc = 0; list_splice(&tmp_list, &atchan->free_list); dma_cookie_init(chan); spin_unlock_irqrestore(&atchan->lock, flags); @@ -1185,6 +1253,7 @@ static void atc_free_chan_resources(struct dma_chan *chan) list_splice_init(&atchan->free_list, &list); atchan->descs_allocated = 0; atchan->status = 0; + atchan->remain_desc = 0; dev_vdbg(chan2dev(chan), "free_chan_resources: done\n"); } @@ -1223,14 +1292,31 @@ static struct dma_chan *at_dma_xlate(struct of_phandle_args *dma_spec, atslave = devm_kzalloc(&dmac_pdev->dev, sizeof(*atslave), GFP_KERNEL); if (!atslave) return NULL; + + atslave->cfg = ATC_DST_H2SEL_HW | ATC_SRC_H2SEL_HW; /* * We can fill both SRC_PER and DST_PER, one of these fields will be * ignored depending on DMA transfer direction. */ - per_id = dma_spec->args[1]; - atslave->cfg = ATC_FIFOCFG_HALFFIFO | ATC_DST_H2SEL_HW - | ATC_SRC_H2SEL_HW | ATC_DST_PER(per_id) - | ATC_SRC_PER(per_id); + per_id = dma_spec->args[1] & AT91_DMA_CFG_PER_ID_MASK; + atslave->cfg |= ATC_DST_PER_MSB(per_id) | ATC_DST_PER(per_id) + | ATC_SRC_PER_MSB(per_id) | ATC_SRC_PER(per_id); + /* + * We have to translate the value we get from the device tree since + * the half FIFO configuration value had to be 0 to keep backward + * compatibility. + */ + switch (dma_spec->args[1] & AT91_DMA_CFG_FIFOCFG_MASK) { + case AT91_DMA_CFG_FIFOCFG_ALAP: + atslave->cfg |= ATC_FIFOCFG_LARGESTBURST; + break; + case AT91_DMA_CFG_FIFOCFG_ASAP: + atslave->cfg |= ATC_FIFOCFG_ENOUGHSPACE; + break; + case AT91_DMA_CFG_FIFOCFG_HALF: + default: + atslave->cfg |= ATC_FIFOCFG_HALFFIFO; + } atslave->dma_dev = &dmac_pdev->dev; chan = dma_request_channel(mask, at_dma_filter, atslave); @@ -1374,7 +1460,9 @@ static int __init at_dma_probe(struct platform_device *pdev) err = PTR_ERR(atdma->clk); goto err_clk; } - clk_enable(atdma->clk); + err = clk_prepare_enable(atdma->clk); + if (err) + goto err_clk_prepare; /* force dma off, just in case */ at_dma_off(atdma); @@ -1472,10 +1560,10 @@ err_of_dma_controller_register: dma_async_device_unregister(&atdma->dma_common); dma_pool_destroy(atdma->dma_desc_pool); err_pool_create: - platform_set_drvdata(pdev, NULL); free_irq(platform_get_irq(pdev, 0), atdma); err_irq: - clk_disable(atdma->clk); + clk_disable_unprepare(atdma->clk); +err_clk_prepare: clk_put(atdma->clk); err_clk: iounmap(atdma->regs); @@ -1497,7 +1585,6 @@ static int at_dma_remove(struct platform_device *pdev) dma_async_device_unregister(&atdma->dma_common); dma_pool_destroy(atdma->dma_desc_pool); - platform_set_drvdata(pdev, NULL); free_irq(platform_get_irq(pdev, 0), atdma); list_for_each_entry_safe(chan, _chan, &atdma->dma_common.channels, @@ -1512,7 +1599,7 @@ static int at_dma_remove(struct platform_device *pdev) list_del(&chan->device_node); } - clk_disable(atdma->clk); + clk_disable_unprepare(atdma->clk); clk_put(atdma->clk); iounmap(atdma->regs); @@ -1531,7 +1618,7 @@ static void at_dma_shutdown(struct platform_device *pdev) struct at_dma *atdma = platform_get_drvdata(pdev); at_dma_off(platform_get_drvdata(pdev)); - clk_disable(atdma->clk); + clk_disable_unprepare(atdma->clk); } static int at_dma_prepare(struct device *dev) @@ -1588,7 +1675,7 @@ static int at_dma_suspend_noirq(struct device *dev) /* disable DMA controller */ at_dma_off(atdma); - clk_disable(atdma->clk); + clk_disable_unprepare(atdma->clk); return 0; } @@ -1618,7 +1705,7 @@ static int at_dma_resume_noirq(struct device *dev) struct dma_chan *chan, *_chan; /* bring back DMA controller */ - clk_enable(atdma->clk); + clk_prepare_enable(atdma->clk); dma_writel(atdma, EN, AT_DMA_ENABLE); /* clear any pending interrupt */ |