From beeaa103eecc7a132682c40867f0ef70655383a5 Mon Sep 17 00:00:00 2001 From: Nicolas Ferre Date: Wed, 14 Mar 2012 12:41:43 +0100 Subject: dmaengine: at_hdmac: add slave config operation This patch introduces DMA_SLAVE_CONFIG to at_hdmac Atmel DMA driver. It is needed to fix a regression in the use of atmel-mci.c driver on Atmel AT91 platforms brouth by e2b35f3: "dmaengine/dw_dmac: Fix dw_dmac user drivers to adapt to slave_config changes" We remove some parts of the private structure "at_dma_slave" and use the information provided by "struct dma_slave_config": source/destination peripheral registers and access width. AT_DMA_SLAVE_WIDTH_* values used previously are not needed anymore as we now use the standard ones. Although some conversion functions are needed to match register expected values. Some AT91 sub-architecture specific files are slightly touched by this patch but it cannot be split because it can break compilation. Signed-off-by: Nicolas Ferre Signed-off-by: Vinod Koul --- drivers/dma/at_hdmac.c | 56 ++++++++++++++++++++++++++++++++++----------- drivers/dma/at_hdmac_regs.h | 32 ++++++++++++++++++++++++++ 2 files changed, 75 insertions(+), 13 deletions(-) (limited to 'drivers/dma') diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c index f24b16e455fd..7aa58d204892 100644 --- a/drivers/dma/at_hdmac.c +++ b/drivers/dma/at_hdmac.c @@ -648,6 +648,7 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, { struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_dma_slave *atslave = chan->private; + struct dma_slave_config *sconfig = &atchan->dma_sconfig; struct at_desc *first = NULL; struct at_desc *prev = NULL; u32 ctrla; @@ -669,19 +670,18 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, return NULL; } - reg_width = atslave->reg_width; - ctrla = ATC_DEFAULT_CTRLA | atslave->ctrla; ctrlb = ATC_IEN; switch (direction) { case DMA_MEM_TO_DEV: + reg_width = convert_buswidth(sconfig->dst_addr_width); ctrla |= ATC_DST_WIDTH(reg_width); ctrlb |= ATC_DST_ADDR_MODE_FIXED | ATC_SRC_ADDR_MODE_INCR | ATC_FC_MEM2PER | ATC_SIF(AT_DMA_MEM_IF) | ATC_DIF(AT_DMA_PER_IF); - reg = atslave->tx_reg; + reg = sconfig->dst_addr; for_each_sg(sgl, sg, sg_len, i) { struct at_desc *desc; u32 len; @@ -709,13 +709,14 @@ atc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, } break; case DMA_DEV_TO_MEM: + reg_width = convert_buswidth(sconfig->src_addr_width); ctrla |= ATC_SRC_WIDTH(reg_width); ctrlb |= ATC_DST_ADDR_MODE_INCR | ATC_SRC_ADDR_MODE_FIXED | ATC_FC_PER2MEM | ATC_SIF(AT_DMA_PER_IF) | ATC_DIF(AT_DMA_MEM_IF); - reg = atslave->rx_reg; + reg = sconfig->src_addr; for_each_sg(sgl, sg, sg_len, i) { struct at_desc *desc; u32 len; @@ -791,12 +792,15 @@ err_out: * atc_dma_cyclic_fill_desc - Fill one period decriptor */ static int -atc_dma_cyclic_fill_desc(struct at_dma_slave *atslave, struct at_desc *desc, +atc_dma_cyclic_fill_desc(struct dma_chan *chan, struct at_desc *desc, unsigned int period_index, dma_addr_t buf_addr, - size_t period_len, enum dma_transfer_direction direction) + unsigned int reg_width, size_t period_len, + enum dma_transfer_direction direction) { - u32 ctrla; - unsigned int reg_width = atslave->reg_width; + struct at_dma_chan *atchan = to_at_dma_chan(chan); + struct at_dma_slave *atslave = chan->private; + struct dma_slave_config *sconfig = &atchan->dma_sconfig; + u32 ctrla; /* prepare common CRTLA value */ ctrla = ATC_DEFAULT_CTRLA | atslave->ctrla @@ -807,7 +811,7 @@ atc_dma_cyclic_fill_desc(struct at_dma_slave *atslave, struct at_desc *desc, switch (direction) { case DMA_MEM_TO_DEV: desc->lli.saddr = buf_addr + (period_len * period_index); - desc->lli.daddr = atslave->tx_reg; + desc->lli.daddr = sconfig->dst_addr; desc->lli.ctrla = ctrla; desc->lli.ctrlb = ATC_DST_ADDR_MODE_FIXED | ATC_SRC_ADDR_MODE_INCR @@ -817,7 +821,7 @@ atc_dma_cyclic_fill_desc(struct at_dma_slave *atslave, struct at_desc *desc, break; case DMA_DEV_TO_MEM: - desc->lli.saddr = atslave->rx_reg; + desc->lli.saddr = sconfig->src_addr; desc->lli.daddr = buf_addr + (period_len * period_index); desc->lli.ctrla = ctrla; desc->lli.ctrlb = ATC_DST_ADDR_MODE_INCR @@ -850,9 +854,11 @@ atc_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len, { struct at_dma_chan *atchan = to_at_dma_chan(chan); struct at_dma_slave *atslave = chan->private; + struct dma_slave_config *sconfig = &atchan->dma_sconfig; struct at_desc *first = NULL; struct at_desc *prev = NULL; unsigned long was_cyclic; + unsigned int reg_width; unsigned int periods = buf_len / period_len; unsigned int i; @@ -872,8 +878,13 @@ atc_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len, return NULL; } + if (sconfig->direction == DMA_MEM_TO_DEV) + reg_width = convert_buswidth(sconfig->dst_addr_width); + else + reg_width = convert_buswidth(sconfig->src_addr_width); + /* Check for too big/unaligned periods and unaligned DMA buffer */ - if (atc_dma_cyclic_check_values(atslave->reg_width, buf_addr, + if (atc_dma_cyclic_check_values(reg_width, buf_addr, period_len, direction)) goto err_out; @@ -885,8 +896,8 @@ atc_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len, if (!desc) goto err_desc_get; - if (atc_dma_cyclic_fill_desc(atslave, desc, i, buf_addr, - period_len, direction)) + if (atc_dma_cyclic_fill_desc(chan, desc, i, buf_addr, + reg_width, period_len, direction)) goto err_desc_get; atc_desc_chain(&first, &prev, desc); @@ -909,6 +920,23 @@ err_out: return NULL; } +static int set_runtime_config(struct dma_chan *chan, + struct dma_slave_config *sconfig) +{ + struct at_dma_chan *atchan = to_at_dma_chan(chan); + + /* Check if it is chan is configured for slave transfers */ + if (!chan->private) + return -EINVAL; + + memcpy(&atchan->dma_sconfig, sconfig, sizeof(*sconfig)); + + convert_burst(&atchan->dma_sconfig.src_maxburst); + convert_burst(&atchan->dma_sconfig.dst_maxburst); + + return 0; +} + static int atc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, unsigned long arg) @@ -969,6 +997,8 @@ static int atc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, clear_bit(ATC_IS_CYCLIC, &atchan->status); spin_unlock_irqrestore(&atchan->lock, flags); + } else if (cmd == DMA_SLAVE_CONFIG) { + return set_runtime_config(chan, (struct dma_slave_config *)arg); } else { return -ENXIO; } diff --git a/drivers/dma/at_hdmac_regs.h b/drivers/dma/at_hdmac_regs.h index 08fd8a0ae797..897a8bcaec90 100644 --- a/drivers/dma/at_hdmac_regs.h +++ b/drivers/dma/at_hdmac_regs.h @@ -207,6 +207,7 @@ enum atc_status { * @save_cfg: configuration register that is saved on suspend/resume cycle * @save_dscr: for cyclic operations, preserve next descriptor address in * the cyclic list on suspend/resume cycle + * @dma_sconfig: configuration for slave transfers, passed via DMA_SLAVE_CONFIG * @lock: serializes enqueue/dequeue operations to descriptors lists * @active_list: list of descriptors dmaengine is being running on * @queue: list of descriptors ready to be submitted to engine @@ -222,6 +223,7 @@ struct at_dma_chan { struct tasklet_struct tasklet; u32 save_cfg; u32 save_dscr; + struct dma_slave_config dma_sconfig; spinlock_t lock; @@ -243,6 +245,36 @@ static inline struct at_dma_chan *to_at_dma_chan(struct dma_chan *dchan) return container_of(dchan, struct at_dma_chan, chan_common); } +/* + * Fix sconfig's burst size according to at_hdmac. We need to convert them as: + * 1 -> 0, 4 -> 1, 8 -> 2, 16 -> 3, 32 -> 4, 64 -> 5, 128 -> 6, 256 -> 7. + * + * This can be done by finding most significant bit set. + */ +static inline void convert_burst(u32 *maxburst) +{ + if (*maxburst > 1) + *maxburst = fls(*maxburst) - 2; + else + *maxburst = 0; +} + +/* + * Fix sconfig's bus width according to at_hdmac. + * 1 byte -> 0, 2 bytes -> 1, 4 bytes -> 2. + */ +static inline u8 convert_buswidth(enum dma_slave_buswidth addr_width) +{ + switch (addr_width) { + case DMA_SLAVE_BUSWIDTH_2_BYTES: + return 1; + case DMA_SLAVE_BUSWIDTH_4_BYTES: + return 2; + default: + /* For 1 byte width or fallback */ + return 0; + } +} /*-- Controller ------------------------------------------------------*/ -- cgit v1.2.3-59-g8ed1b