From 32286e2793858a8491c2276b2754e9850467bb6b Mon Sep 17 00:00:00 2001 From: Pandith N Date: Mon, 2 Aug 2021 11:24:52 +0530 Subject: [PATCH] dmaengine: dw-axi-dmac: Remove free slot check algorithm in dw_axi_dma_set_hw_channel Removed free slot check algorithm in dw_axi_dma_set_hw_channel. For 8 DMA channels, use respective handshake slot in DMA_HS_SEL APB register. For every channel, an dedicated slot is provided in hardware handshake register AXIDMA_CTRL_DMA_HS_SEL_n. Peripheral source number is programmed in respective channel slots. Signed-off-by: Pandith N Tested-by: Pan Kris Link: https://lore.kernel.org/r/20210802055454.15192-2-pandith.n@intel.com Signed-off-by: Vinod Koul --- .../dma/dw-axi-dmac/dw-axi-dmac-platform.c | 49 +++++++------------ drivers/dma/dw-axi-dmac/dw-axi-dmac.h | 2 + 2 files changed, 21 insertions(+), 30 deletions(-) diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c index d9e4ac3edb4e..c3bb2b4820a3 100644 --- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c +++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c @@ -470,18 +470,13 @@ static void dma_chan_free_chan_resources(struct dma_chan *dchan) pm_runtime_put(chan->chip->dev); } -static void dw_axi_dma_set_hw_channel(struct axi_dma_chip *chip, - u32 handshake_num, bool set) +static void dw_axi_dma_set_hw_channel(struct axi_dma_chan *chan, bool set) { - unsigned long start = 0; - unsigned long reg_value; - unsigned long reg_mask; - unsigned long reg_set; - unsigned long mask; - unsigned long val; + struct axi_dma_chip *chip = chan->chip; + unsigned long reg_value, val; if (!chip->apb_regs) { - dev_dbg(chip->dev, "apb_regs not initialized\n"); + dev_err(chip->dev, "apb_regs not initialized\n"); return; } @@ -490,26 +485,22 @@ static void dw_axi_dma_set_hw_channel(struct axi_dma_chip *chip, * Lock the DMA channel by assign a handshake number to the channel. * Unlock the DMA channel by assign 0x3F to the channel. */ - if (set) { - reg_set = UNUSED_CHANNEL; - val = handshake_num; - } else { - reg_set = handshake_num; + if (set) + val = chan->hw_handshake_num; + else val = UNUSED_CHANNEL; - } reg_value = lo_hi_readq(chip->apb_regs + DMAC_APB_HW_HS_SEL_0); - for_each_set_clump8(start, reg_mask, ®_value, 64) { - if (reg_mask == reg_set) { - mask = GENMASK_ULL(start + 7, start); - reg_value &= ~mask; - reg_value |= rol64(val, start); - lo_hi_writeq(reg_value, - chip->apb_regs + DMAC_APB_HW_HS_SEL_0); - break; - } - } + /* Channel is already allocated, set handshake as per channel ID */ + /* 64 bit write should handle for 8 channels */ + + reg_value &= ~(DMA_APB_HS_SEL_MASK << + (chan->id * DMA_APB_HS_SEL_BIT_SIZE)); + reg_value |= (val << (chan->id * DMA_APB_HS_SEL_BIT_SIZE)); + lo_hi_writeq(reg_value, chip->apb_regs + DMAC_APB_HW_HS_SEL_0); + + return; } /* @@ -742,7 +733,7 @@ dw_axi_dma_chan_prep_cyclic(struct dma_chan *dchan, dma_addr_t dma_addr, llp = hw_desc->llp; } while (total_segments); - dw_axi_dma_set_hw_channel(chan->chip, chan->hw_handshake_num, true); + dw_axi_dma_set_hw_channel(chan, true); return vchan_tx_prep(&chan->vc, &desc->vd, flags); @@ -822,7 +813,7 @@ dw_axi_dma_chan_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl, llp = hw_desc->llp; } while (num_sgs); - dw_axi_dma_set_hw_channel(chan->chip, chan->hw_handshake_num, true); + dw_axi_dma_set_hw_channel(chan, true); return vchan_tx_prep(&chan->vc, &desc->vd, flags); @@ -1098,8 +1089,7 @@ static int dma_chan_terminate_all(struct dma_chan *dchan) "%s failed to stop\n", axi_chan_name(chan)); if (chan->direction != DMA_MEM_TO_MEM) - dw_axi_dma_set_hw_channel(chan->chip, - chan->hw_handshake_num, false); + dw_axi_dma_set_hw_channel(chan, false); if (chan->direction == DMA_MEM_TO_DEV) dw_axi_dma_set_byte_halfword(chan, false); @@ -1365,7 +1355,6 @@ static int dw_probe(struct platform_device *pdev) if (ret) return ret; - INIT_LIST_HEAD(&dw->dma.channels); for (i = 0; i < hdata->nr_channels; i++) { struct axi_dma_chan *chan = &dw->chan[i]; diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac.h b/drivers/dma/dw-axi-dmac/dw-axi-dmac.h index b69897887c76..358f553cafe9 100644 --- a/drivers/dma/dw-axi-dmac/dw-axi-dmac.h +++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac.h @@ -184,6 +184,8 @@ static inline struct axi_dma_chan *dchan_to_axi_dma_chan(struct dma_chan *dchan) #define DMAC_APB_HALFWORD_WR_CH_EN 0x020 /* DMAC Halfword write enables */ #define UNUSED_CHANNEL 0x3F /* Set unused DMA channel to 0x3F */ +#define DMA_APB_HS_SEL_BIT_SIZE 0x08 /* HW handshake bits per channel */ +#define DMA_APB_HS_SEL_MASK 0xFF /* HW handshake select masks */ #define MAX_BLOCK_SIZE 0x1000 /* 1024 blocks * 4 bytes data width */ /* DMAC_CFG */