From 3e1070bb4257f637414242a7116ec9bd50d07b5f Mon Sep 17 00:00:00 2001 From: Sia Jee Heng Date: Thu, 21 Jan 2021 13:56:39 +0800 Subject: [PATCH] dmaengine: dw-axi-dmac: Add Intel KeemBay AxiDMA BYTE and HALFWORD registers Add support for Intel KeemBay AxiDMA BYTE and HALFWORD registers programming. Intel KeemBay AxiDMA supports data transfer between device to memory and memory to device operations. This code is needed by I2C, I3C, I2S, SPI and UART which uses FIFO size of 8bits and 16bits to perform memory to device data transfer operation. 0-padding functionality is provided to avoid pre-processing of data on CPU. Signed-off-by: Sia Jee Heng Reviewed-by: Andy Shevchenko Reviewed-by: Eugeniy Paltsev Tested-by: Eugeniy Paltsev --- .../dma/dw-axi-dmac/dw-axi-dmac-platform.c | 27 +++++++++++++++++++ 1 file changed, 27 insertions(+) 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 e19369f9365a39..ea527b92e0fc18 100644 --- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c +++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c @@ -307,6 +307,30 @@ static void write_chan_llp(struct axi_dma_chan *chan, dma_addr_t adr) axi_chan_iowrite64(chan, CH_LLP, adr); } +static void dw_axi_dma_set_byte_halfword(struct axi_dma_chan *chan, bool set) +{ + u32 reg_width, offset, val; + + if (!chan->chip->apb_regs) { + dev_dbg(chan->chip->dev, "apb_regs not initialized\n"); + return; + } + + reg_width = __ffs(chan->config.dst_addr_width); + if (reg_width == DWAXIDMAC_TRANS_WIDTH_8) + offset = DMAC_APB_BYTE_WR_CH_EN; + else if (reg_width == DWAXIDMAC_TRANS_WIDTH_16) + offset = DMAC_APB_HALFWORD_WR_CH_EN; + + val = ioread32(chan->chip->apb_regs + offset); + + if (set) + val |= BIT(chan->id); + else + val &= ~BIT(chan->id); + + iowrite32(val, chan->chip->apb_regs + offset); +} /* Called in chan locked context */ static void axi_chan_block_xfer_start(struct axi_dma_chan *chan, struct axi_dma_desc *first) @@ -334,6 +358,7 @@ static void axi_chan_block_xfer_start(struct axi_dma_chan *chan, DWAXIDMAC_HS_SEL_HW << CH_CFG_H_HS_SEL_SRC_POS); switch (chan->direction) { case DMA_MEM_TO_DEV: + dw_axi_dma_set_byte_halfword(chan, true); reg |= (chan->config.device_fc ? DWAXIDMAC_TT_FC_MEM_TO_PER_DST : DWAXIDMAC_TT_FC_MEM_TO_PER_DMAC) @@ -1008,6 +1033,8 @@ static int dma_chan_terminate_all(struct dma_chan *dchan) if (chan->direction != DMA_MEM_TO_MEM) dw_axi_dma_set_hw_channel(chan->chip, chan->hw_handshake_num, false); + if (chan->direction == DMA_MEM_TO_DEV) + dw_axi_dma_set_byte_halfword(chan, false); spin_lock_irqsave(&chan->vc.lock, flags);