From 2e65060e803e046fc9b5ed0107494a452424845e Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Wed, 27 Apr 2016 14:15:38 +0300 Subject: [PATCH] dmaengine: dw: revisit data_width property There several changes are done here: - Convert the property to be in bytes Besides that this is a common practice for such property, the use of a value in bytes much more convenient than handling the encoded one. - Rename data_width to data-width in the device tree bindings The change leaves the support for the old format as well just in case someone will use a newer kernel with an old device tree blob. - While here, replace dwc_fast_ffs() by __ffs() Signed-off-by: Andy Shevchenko Acked-by: Viresh Kumar Signed-off-by: Vinod Koul --- .../devicetree/bindings/dma/snps-dma.txt | 7 +++- arch/arc/boot/dts/abilis_tb10x.dtsi | 2 +- arch/arm/boot/dts/spear13xx.dtsi | 4 +- drivers/dma/dw/core.c | 42 +++++-------------- drivers/dma/dw/platform.c | 5 ++- include/linux/platform_data/dma-dw.h | 2 +- 6 files changed, 24 insertions(+), 38 deletions(-) diff --git a/Documentation/devicetree/bindings/dma/snps-dma.txt b/Documentation/devicetree/bindings/dma/snps-dma.txt index c99c1ffac199..0f5583293c9c 100644 --- a/Documentation/devicetree/bindings/dma/snps-dma.txt +++ b/Documentation/devicetree/bindings/dma/snps-dma.txt @@ -13,6 +13,11 @@ Required properties: - chan_priority: priority of channels. 0 (default): increase from chan 0->n, 1: increase from chan n->0 - block_size: Maximum block size supported by the controller +- data-width: Maximum data width supported by hardware per AHB master + (in bytes, power of 2) + + +Deprecated properties: - data_width: Maximum data width supported by hardware per AHB master (0 - 8bits, 1 - 16bits, ..., 5 - 256bits) @@ -38,7 +43,7 @@ Example: chan_allocation_order = <1>; chan_priority = <1>; block_size = <0xfff>; - data_width = <3 3>; + data-width = <8 8>; }; DMA clients connected to the Designware DMA controller must use the format diff --git a/arch/arc/boot/dts/abilis_tb10x.dtsi b/arch/arc/boot/dts/abilis_tb10x.dtsi index cfb5052239a1..2f53bedb0cde 100644 --- a/arch/arc/boot/dts/abilis_tb10x.dtsi +++ b/arch/arc/boot/dts/abilis_tb10x.dtsi @@ -112,7 +112,7 @@ chan_allocation_order = <0>; chan_priority = <1>; block_size = <0x7ff>; - data_width = <2>; + data-width = <4>; clocks = <&ahb_clk>; clock-names = "hclk"; }; diff --git a/arch/arm/boot/dts/spear13xx.dtsi b/arch/arm/boot/dts/spear13xx.dtsi index 14594ce8c18a..449acf0d8272 100644 --- a/arch/arm/boot/dts/spear13xx.dtsi +++ b/arch/arm/boot/dts/spear13xx.dtsi @@ -117,7 +117,7 @@ chan_priority = <1>; block_size = <0xfff>; dma-masters = <2>; - data_width = <3 3>; + data-width = <8 8>; }; dma@eb000000 { @@ -133,7 +133,7 @@ chan_allocation_order = <1>; chan_priority = <1>; block_size = <0xfff>; - data_width = <3 3>; + data-width = <8 8>; }; fsmc: flash@b0000000 { diff --git a/drivers/dma/dw/core.c b/drivers/dma/dw/core.c index 78522dcf3a7d..992da255b8e6 100644 --- a/drivers/dma/dw/core.c +++ b/drivers/dma/dw/core.c @@ -162,21 +162,6 @@ static void dwc_initialize(struct dw_dma_chan *dwc) /*----------------------------------------------------------------------*/ -static inline unsigned int dwc_fast_ffs(unsigned long long v) -{ - /* - * We can be a lot more clever here, but this should take care - * of the most common optimization. - */ - if (!(v & 7)) - return 3; - else if (!(v & 3)) - return 2; - else if (!(v & 1)) - return 1; - return 0; -} - static inline void dwc_dump_chan_regs(struct dw_dma_chan *dwc) { dev_err(chan2dev(&dwc->chan), @@ -677,11 +662,12 @@ dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, struct dw_desc *prev; size_t xfer_count; size_t offset; + u8 m_master = dwc->m_master; unsigned int src_width; unsigned int dst_width; - unsigned int data_width; + unsigned int data_width = dw->data_width[m_master]; u32 ctllo; - u8 lms = DWC_LLP_LMS(dwc->m_master); + u8 lms = DWC_LLP_LMS(m_master); dev_vdbg(chan2dev(chan), "%s: d%pad s%pad l0x%zx f0x%lx\n", __func__, @@ -694,10 +680,7 @@ dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, dwc->direction = DMA_MEM_TO_MEM; - data_width = dw->data_width[dwc->m_master]; - - src_width = dst_width = min_t(unsigned int, data_width, - dwc_fast_ffs(src | dest | len)); + src_width = dst_width = __ffs(data_width | src | dest | len); ctllo = DWC_DEFAULT_CTLLO(chan) | DWC_CTLL_DST_WIDTH(dst_width) @@ -757,11 +740,12 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, struct dw_desc *prev; struct dw_desc *first; u32 ctllo; - u8 lms = DWC_LLP_LMS(dwc->m_master); + u8 m_master = dwc->m_master; + u8 lms = DWC_LLP_LMS(m_master); dma_addr_t reg; unsigned int reg_width; unsigned int mem_width; - unsigned int data_width; + unsigned int data_width = dw->data_width[m_master]; unsigned int i; struct scatterlist *sg; size_t total_len = 0; @@ -787,8 +771,6 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, ctllo |= sconfig->device_fc ? DWC_CTLL_FC(DW_DMA_FC_P_M2P) : DWC_CTLL_FC(DW_DMA_FC_D_M2P); - data_width = dw->data_width[dwc->m_master]; - for_each_sg(sgl, sg, sg_len, i) { struct dw_desc *desc; u32 len, dlen, mem; @@ -796,8 +778,7 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, mem = sg_dma_address(sg); len = sg_dma_len(sg); - mem_width = min_t(unsigned int, - data_width, dwc_fast_ffs(mem | len)); + mem_width = __ffs(data_width | mem | len); slave_sg_todev_fill_desc: desc = dwc_desc_get(dwc); @@ -843,8 +824,6 @@ slave_sg_todev_fill_desc: ctllo |= sconfig->device_fc ? DWC_CTLL_FC(DW_DMA_FC_P_P2M) : DWC_CTLL_FC(DW_DMA_FC_D_P2M); - data_width = dw->data_width[dwc->m_master]; - for_each_sg(sgl, sg, sg_len, i) { struct dw_desc *desc; u32 len, dlen, mem; @@ -852,8 +831,7 @@ slave_sg_todev_fill_desc: mem = sg_dma_address(sg); len = sg_dma_len(sg); - mem_width = min_t(unsigned int, - data_width, dwc_fast_ffs(mem | len)); + mem_width = __ffs(data_width | mem | len); slave_sg_fromdev_fill_desc: desc = dwc_desc_get(dwc); @@ -1500,7 +1478,7 @@ int dw_dma_probe(struct dw_dma_chip *chip, struct dw_dma_platform_data *pdata) pdata->nr_masters = (dw_params >> DW_PARAMS_NR_MASTER & 3) + 1; for (i = 0; i < pdata->nr_masters; i++) { pdata->data_width[i] = - (dw_params >> DW_PARAMS_DATA_WIDTH(i) & 3) + 2; + 4 << (dw_params >> DW_PARAMS_DATA_WIDTH(i) & 3); } max_blk_size = dma_readl(dw, MAX_BLK_SIZE); diff --git a/drivers/dma/dw/platform.c b/drivers/dma/dw/platform.c index e65ebe5ab88f..2420fb7267bc 100644 --- a/drivers/dma/dw/platform.c +++ b/drivers/dma/dw/platform.c @@ -138,9 +138,12 @@ dw_dma_parse_dt(struct platform_device *pdev) if (!of_property_read_u32(np, "block_size", &tmp)) pdata->block_size = tmp; - if (!of_property_read_u32_array(np, "data_width", arr, nr_masters)) { + if (!of_property_read_u32_array(np, "data-width", arr, nr_masters)) { for (tmp = 0; tmp < nr_masters; tmp++) pdata->data_width[tmp] = arr[tmp]; + } else if (!of_property_read_u32_array(np, "data_width", arr, nr_masters)) { + for (tmp = 0; tmp < nr_masters; tmp++) + pdata->data_width[tmp] = BIT(arr[tmp] & 0x07); } return pdata; diff --git a/include/linux/platform_data/dma-dw.h b/include/linux/platform_data/dma-dw.h index b881b978e486..ad768111c350 100644 --- a/include/linux/platform_data/dma-dw.h +++ b/include/linux/platform_data/dma-dw.h @@ -43,7 +43,7 @@ struct dw_dma_slave { * @block_size: Maximum block size supported by the controller * @nr_masters: Number of AHB masters supported by the controller * @data_width: Maximum data width supported by hardware per AHB master - * (0 - 8bits, 1 - 16bits, ..., 5 - 256bits) + * (in bytes, power of 2) */ struct dw_dma_platform_data { unsigned int nr_channels; -- 2.20.1