In order to have a more coherent DW AHB DMA slave configuration method let's simplify the source and destination channel max-burst calculation procedure: 1. Create the max-burst verification method as it has been just done for the memory and peripheral address widths. Thus the DWC DMA slave config method will turn to a set of the verification methods execution. 2. Since both the generic DW AHB DMA and Intel DMA32 engines support the power-of-2 bursts only, then the specified by the client driver max-burst values can be converted to being power-of-2 right in the max-burst verification method. 3. Since max-burst encoded value is required on the CTL_LO fields calculation stage, the encode_maxburst() callback can be easily dropped from the dw_dma structure meanwhile the encoding procedure will be executed right in the CTL_LO register value calculation. Thus the update will provide the next positive effects: the internal DMA-slave config structure will contain only the real DMA-transfer config value, which will be encoded to the DMA-controller register fields only when it's required on the buffer mapping; the redundant encode_maxburst() callback will be dropped simplifying the internal HW-abstraction API; DWC-config method will look more readable executing the verification functions one-by-one. Signed-off-by: Serge Semin <fancer.lancer@xxxxxxxxx> --- drivers/dma/dw/core.c | 26 +++++++++++++++++--------- drivers/dma/dw/dw.c | 23 +++++++++++------------ drivers/dma/dw/idma32.c | 15 +++++++-------- drivers/dma/dw/regs.h | 1 - 4 files changed, 35 insertions(+), 30 deletions(-) diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c index 61e026310dd8..8b4ecd137ae2 100644 --- a/drivers/dma/dw/core.c +++ b/drivers/dma/dw/core.c @@ -779,6 +779,21 @@ bool dw_dma_filter(struct dma_chan *chan, void *param) } EXPORT_SYMBOL_GPL(dw_dma_filter); +static void dwc_verify_maxburst(struct dma_chan *chan) +{ + struct dw_dma_chan *dwc = to_dw_dma_chan(chan); + + dwc->dma_sconfig.src_maxburst = + clamp(dwc->dma_sconfig.src_maxburst, 1U, dwc->max_burst); + dwc->dma_sconfig.dst_maxburst = + clamp(dwc->dma_sconfig.dst_maxburst, 1U, dwc->max_burst); + + dwc->dma_sconfig.src_maxburst = + rounddown_pow_of_two(dwc->dma_sconfig.src_maxburst); + dwc->dma_sconfig.dst_maxburst = + rounddown_pow_of_two(dwc->dma_sconfig.dst_maxburst); +} + static int dwc_verify_p_buswidth(struct dma_chan *chan) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); @@ -828,7 +843,7 @@ static int dwc_verify_m_buswidth(struct dma_chan *chan) dwc->dma_sconfig.src_addr_width = mem_width; } else if (dwc->dma_sconfig.direction == DMA_DEV_TO_MEM) { reg_width = dwc->dma_sconfig.src_addr_width; - reg_burst = rounddown_pow_of_two(dwc->dma_sconfig.src_maxburst); + reg_burst = dwc->dma_sconfig.src_maxburst; dwc->dma_sconfig.dst_addr_width = min(mem_width, reg_width * reg_burst); } @@ -839,15 +854,11 @@ static int dwc_verify_m_buswidth(struct dma_chan *chan) static int dwc_config(struct dma_chan *chan, struct dma_slave_config *sconfig) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); - struct dw_dma *dw = to_dw_dma(chan->device); int err; memcpy(&dwc->dma_sconfig, sconfig, sizeof(*sconfig)); - dwc->dma_sconfig.src_maxburst = - clamp(dwc->dma_sconfig.src_maxburst, 1U, dwc->max_burst); - dwc->dma_sconfig.dst_maxburst = - clamp(dwc->dma_sconfig.dst_maxburst, 1U, dwc->max_burst); + dwc_verify_maxburst(chan); err = dwc_verify_p_buswidth(chan); if (err) @@ -857,9 +868,6 @@ static int dwc_config(struct dma_chan *chan, struct dma_slave_config *sconfig) if (err) return err; - dw->encode_maxburst(dwc, &dwc->dma_sconfig.src_maxburst); - dw->encode_maxburst(dwc, &dwc->dma_sconfig.dst_maxburst); - return 0; } diff --git a/drivers/dma/dw/dw.c b/drivers/dma/dw/dw.c index c65438d1f1ff..c52333646edd 100644 --- a/drivers/dma/dw/dw.c +++ b/drivers/dma/dw/dw.c @@ -64,6 +64,15 @@ static size_t dw_dma_block2bytes(struct dw_dma_chan *dwc, u32 block, u32 width) return DWC_CTLH_BLOCK_TS(block) << width; } +static inline u8 dw_dma_encode_maxburst(u32 maxburst) +{ + /* + * Fix burst size according to dw_dmac. We need to convert them as: + * 1 -> 0, 4 -> 1, 8 -> 2, 16 -> 3. + */ + return maxburst > 1 ? fls(maxburst) - 2 : 0; +} + static u32 dw_dma_prepare_ctllo(struct dw_dma_chan *dwc) { struct dma_slave_config *sconfig = &dwc->dma_sconfig; @@ -73,10 +82,10 @@ static u32 dw_dma_prepare_ctllo(struct dw_dma_chan *dwc) sms = dwc->dws.m_master; smsize = 0; dms = dwc->dws.p_master; - dmsize = sconfig->dst_maxburst; + dmsize = dw_dma_encode_maxburst(sconfig->dst_maxburst); } else if (dwc->direction == DMA_DEV_TO_MEM) { sms = dwc->dws.p_master; - smsize = sconfig->src_maxburst; + smsize = dw_dma_encode_maxburst(sconfig->src_maxburst); dms = dwc->dws.m_master; dmsize = 0; } else /* DMA_MEM_TO_MEM */ { @@ -91,15 +100,6 @@ static u32 dw_dma_prepare_ctllo(struct dw_dma_chan *dwc) DWC_CTLL_DMS(dms) | DWC_CTLL_SMS(sms); } -static void dw_dma_encode_maxburst(struct dw_dma_chan *dwc, u32 *maxburst) -{ - /* - * Fix burst size according to dw_dmac. We need to convert them as: - * 1 -> 0, 4 -> 1, 8 -> 2, 16 -> 3. - */ - *maxburst = *maxburst > 1 ? fls(*maxburst) - 2 : 0; -} - static void dw_dma_set_device_name(struct dw_dma *dw, int id) { snprintf(dw->name, sizeof(dw->name), "dw:dmac%d", id); @@ -128,7 +128,6 @@ int dw_dma_probe(struct dw_dma_chip *chip) dw->suspend_chan = dw_dma_suspend_chan; dw->resume_chan = dw_dma_resume_chan; dw->prepare_ctllo = dw_dma_prepare_ctllo; - dw->encode_maxburst = dw_dma_encode_maxburst; dw->bytes2block = dw_dma_bytes2block; dw->block2bytes = dw_dma_block2bytes; diff --git a/drivers/dma/dw/idma32.c b/drivers/dma/dw/idma32.c index 3a1b12517655..428aba9fc2db 100644 --- a/drivers/dma/dw/idma32.c +++ b/drivers/dma/dw/idma32.c @@ -199,6 +199,11 @@ static size_t idma32_block2bytes(struct dw_dma_chan *dwc, u32 block, u32 width) return IDMA32C_CTLH_BLOCK_TS(block); } +static inline u32 idma32_encode_maxburst(u32 maxburst) +{ + return maxburst > 1 ? fls(maxburst) - 1 : 0; +} + static u32 idma32_prepare_ctllo(struct dw_dma_chan *dwc) { struct dma_slave_config *sconfig = &dwc->dma_sconfig; @@ -206,9 +211,9 @@ static u32 idma32_prepare_ctllo(struct dw_dma_chan *dwc) if (dwc->direction == DMA_MEM_TO_DEV) { smsize = 0; - dmsize = sconfig->dst_maxburst; + dmsize = idma32_encode_maxburst(sconfig->dst_maxburst); } else if (dwc->direction == DMA_DEV_TO_MEM) { - smsize = sconfig->src_maxburst; + smsize = idma32_encode_maxburst(sconfig->src_maxburst); dmsize = 0; } else /* DMA_MEM_TO_MEM */ { smsize = 0; @@ -219,11 +224,6 @@ static u32 idma32_prepare_ctllo(struct dw_dma_chan *dwc) DWC_CTLL_DST_MSIZE(dmsize) | DWC_CTLL_SRC_MSIZE(smsize); } -static void idma32_encode_maxburst(struct dw_dma_chan *dwc, u32 *maxburst) -{ - *maxburst = *maxburst > 1 ? fls(*maxburst) - 1 : 0; -} - static void idma32_set_device_name(struct dw_dma *dw, int id) { snprintf(dw->name, sizeof(dw->name), "idma32:dmac%d", id); @@ -280,7 +280,6 @@ int idma32_dma_probe(struct dw_dma_chip *chip) dw->suspend_chan = idma32_suspend_chan; dw->resume_chan = idma32_resume_chan; dw->prepare_ctllo = idma32_prepare_ctllo; - dw->encode_maxburst = idma32_encode_maxburst; dw->bytes2block = idma32_bytes2block; dw->block2bytes = idma32_block2bytes; diff --git a/drivers/dma/dw/regs.h b/drivers/dma/dw/regs.h index 76654bd13c1a..5969d9cc8d7a 100644 --- a/drivers/dma/dw/regs.h +++ b/drivers/dma/dw/regs.h @@ -327,7 +327,6 @@ struct dw_dma { void (*suspend_chan)(struct dw_dma_chan *dwc, bool drain); void (*resume_chan)(struct dw_dma_chan *dwc, bool drain); u32 (*prepare_ctllo)(struct dw_dma_chan *dwc); - void (*encode_maxburst)(struct dw_dma_chan *dwc, u32 *maxburst); u32 (*bytes2block)(struct dw_dma_chan *dwc, size_t bytes, unsigned int width, size_t *len); size_t (*block2bytes)(struct dw_dma_chan *dwc, u32 block, u32 width); -- 2.43.0