Just like for the XDMAC, the SoCs that embed the HDMAC don't have any kind of GPU, and need to accelerate a few framebuffer-related operations through their DMA controller. However, unlike the XDMAC, the HDMAC doesn't have the memset capability built-in. That can be easily emulated though, by doing a transfer with a fixed adress on the variable that holds the value we want to set. Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx> --- Changes from v1: - Replaced the dma_alloc_coherent calls by a dma_pool drivers/dma/at_hdmac.c | 124 ++++++++++++++++++++++++++++++++++++++++++-- drivers/dma/at_hdmac_regs.h | 6 +++ 2 files changed, 127 insertions(+), 3 deletions(-) diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c index 59892126d175..44f4891b71ad 100644 --- a/drivers/dma/at_hdmac.c +++ b/drivers/dma/at_hdmac.c @@ -390,6 +390,7 @@ static void atc_chain_complete(struct at_dma_chan *atchan, struct at_desc *desc) { struct dma_async_tx_descriptor *txd = &desc->txd; + struct at_dma *atdma = to_at_dma(atchan->chan_common.device); dev_vdbg(chan2dev(&atchan->chan_common), "descriptor %u complete\n", txd->cookie); @@ -398,6 +399,13 @@ atc_chain_complete(struct at_dma_chan *atchan, struct at_desc *desc) if (!atc_chan_is_cyclic(atchan)) dma_cookie_complete(txd); + /* If the transfer was a memset, free our temporary buffer */ + if (desc->memset) { + dma_pool_free(atdma->memset_pool, desc->memset_vaddr, + desc->memset_paddr); + desc->memset = false; + } + /* move children to free_list */ list_splice_init(&desc->tx_list, &atchan->free_list); /* move myself to free_list */ @@ -820,6 +828,96 @@ err_desc_get: return NULL; } +/** + * atc_prep_dma_memset - prepare a memcpy operation + * @chan: the channel to prepare operation on + * @dest: operation virtual destination address + * @value: value to set memory buffer to + * @len: operation length + * @flags: tx descriptor status flags + */ +static struct dma_async_tx_descriptor * +atc_prep_dma_memset(struct dma_chan *chan, dma_addr_t dest, int value, + size_t len, unsigned long flags) +{ + struct at_dma_chan *atchan = to_at_dma_chan(chan); + struct at_dma *atdma = to_at_dma(chan->device); + struct at_desc *desc = NULL; + size_t xfer_count; + u32 ctrla; + u32 ctrlb; + + dev_vdbg(chan2dev(chan), "%s: d0x%x v0x%x l0x%zx f0x%lx\n", __func__, + dest, value, len, flags); + + if (unlikely(!len)) { + dev_dbg(chan2dev(chan), "%s: length is zero!\n", __func__); + return NULL; + } + + if (!is_dma_fill_aligned(chan->device, dest, 0, len)) { + dev_dbg(chan2dev(chan), "%s: buffer is not aligned\n", + __func__); + return NULL; + } + + xfer_count = len >> 2; + if (xfer_count > ATC_BTSIZE_MAX) { + dev_err(chan2dev(chan), "%s: buffer is too big\n", + __func__); + return NULL; + } + + ctrlb = ATC_DEFAULT_CTRLB | ATC_IEN + | ATC_SRC_ADDR_MODE_FIXED + | ATC_DST_ADDR_MODE_INCR + | ATC_FC_MEM2MEM; + + ctrla = ATC_SRC_WIDTH(2) | + ATC_DST_WIDTH(2); + + desc = atc_desc_get(atchan); + if (!desc) { + dev_err(chan2dev(chan), "%s: can't get a descriptor\n", + __func__); + return NULL; + } + + desc->memset_vaddr = dma_pool_alloc(atdma->memset_pool, GFP_ATOMIC, + &desc->memset_paddr); + if (!desc->memset_vaddr) { + dev_err(chan2dev(chan), "%s: couldn't allocate buffer\n", + __func__); + goto err_put_desc; + } + + *desc->memset_vaddr = value; + desc->memset = true; + + desc->lli.saddr = desc->memset_paddr; + desc->lli.daddr = dest; + desc->lli.ctrla = ctrla | xfer_count; + desc->lli.ctrlb = ctrlb; + + desc->txd.cookie = -EBUSY; + desc->len = len; + desc->total_len = len; + + /* set transfer width for the calculation of the residue */ + desc->tx_width = 2; + + /* set end-of-link on the descriptor */ + set_desc_eol(desc); + + desc->txd.flags = flags; + + return &desc->txd; + +err_put_desc: + atc_desc_put(atchan, desc); + return NULL; +} + /** * atc_prep_slave_sg - prepare descriptors for a DMA_SLAVE transaction @@ -1713,6 +1811,8 @@ static int __init at_dma_probe(struct platform_device *pdev) dma_cap_set(DMA_SG, at91sam9rl_config.cap_mask); dma_cap_set(DMA_INTERLEAVE, at91sam9g45_config.cap_mask); dma_cap_set(DMA_MEMCPY, at91sam9g45_config.cap_mask); + dma_cap_set(DMA_MEMSET, at91sam9g45_config.cap_mask); + dma_cap_set(DMA_PRIVATE, at91sam9g45_config.cap_mask); dma_cap_set(DMA_SLAVE, at91sam9g45_config.cap_mask); dma_cap_set(DMA_SG, at91sam9g45_config.cap_mask); @@ -1776,7 +1876,16 @@ static int __init at_dma_probe(struct platform_device *pdev) if (!atdma->dma_desc_pool) { dev_err(&pdev->dev, "No memory for descriptors dma pool\n"); err = -ENOMEM; - goto err_pool_create; + goto err_desc_pool_create; + } + + /* create a pool of consistent memory blocks for memset blocks */ + atdma->memset_pool = dma_pool_create("at_hdmac_memset_pool", + &pdev->dev, sizeof(int), 4, 0); + if (!atdma->memset_pool) { + dev_err(&pdev->dev, "No memory for memset dma pool\n"); + err = -ENOMEM; + goto err_memset_pool_create; } /* clear any pending interrupt */ @@ -1822,6 +1931,11 @@ static int __init at_dma_probe(struct platform_device *pdev) if (dma_has_cap(DMA_MEMCPY, atdma->dma_common.cap_mask)) atdma->dma_common.device_prep_dma_memcpy = atc_prep_dma_memcpy; + if (dma_has_cap(DMA_MEMSET, atdma->dma_common.cap_mask)) { + atdma->dma_common.device_prep_dma_memset = atc_prep_dma_memset; + atdma->dma_common.fill_align = DMAENGINE_ALIGN_4_BYTES; + } + if (dma_has_cap(DMA_SLAVE, atdma->dma_common.cap_mask)) { atdma->dma_common.device_prep_slave_sg = atc_prep_slave_sg; /* controller can do slave DMA: can trigger cyclic transfers */ @@ -1842,8 +1956,9 @@ static int __init at_dma_probe(struct platform_device *pdev) dma_writel(atdma, EN, AT_DMA_ENABLE); - dev_info(&pdev->dev, "Atmel AHB DMA Controller ( %s%s%s), %d channels\n", + dev_info(&pdev->dev, "Atmel AHB DMA Controller ( %s%s%s%s), %d channels\n", dma_has_cap(DMA_MEMCPY, atdma->dma_common.cap_mask) ? "cpy " : "", + dma_has_cap(DMA_MEMSET, atdma->dma_common.cap_mask) ? "set " : "", dma_has_cap(DMA_SLAVE, atdma->dma_common.cap_mask) ? "slave " : "", dma_has_cap(DMA_SG, atdma->dma_common.cap_mask) ? "sg-cpy " : "", plat_dat->nr_channels); @@ -1868,8 +1983,10 @@ static int __init at_dma_probe(struct platform_device *pdev) err_of_dma_controller_register: dma_async_device_unregister(&atdma->dma_common); + dma_pool_destroy(atdma->memset_pool); +err_memset_pool_create: dma_pool_destroy(atdma->dma_desc_pool); -err_pool_create: +err_desc_pool_create: free_irq(platform_get_irq(pdev, 0), atdma); err_irq: clk_disable_unprepare(atdma->clk); @@ -1894,6 +2011,7 @@ static int at_dma_remove(struct platform_device *pdev) at_dma_off(atdma); dma_async_device_unregister(&atdma->dma_common); + dma_pool_destroy(atdma->memset_pool); dma_pool_destroy(atdma->dma_desc_pool); free_irq(platform_get_irq(pdev, 0), atdma); diff --git a/drivers/dma/at_hdmac_regs.h b/drivers/dma/at_hdmac_regs.h index bc8d5ebedd19..a2283886dd87 100644 --- a/drivers/dma/at_hdmac_regs.h +++ b/drivers/dma/at_hdmac_regs.h @@ -201,6 +201,11 @@ struct at_desc { size_t boundary; size_t dst_hole; size_t src_hole; + + /* Memset temporary buffer */ + bool memset; + dma_addr_t memset_paddr; + int *memset_vaddr; }; static inline struct at_desc * @@ -331,6 +336,7 @@ struct at_dma { u8 all_chan_mask; struct dma_pool *dma_desc_pool; + struct dma_pool *memset_pool; /* AT THE END channels table */ struct at_dma_chan chan[0]; }; -- 2.4.5 -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html