Merge remote-tracking branch 'spi/for-5.8' into spi-linus

{

	u16 imr = 0, dma_ctrl = 0;

	/*

	 * Having a Rx DMA channel serviced with higher priority than a Tx DMA

	 * channel might not be enough to provide a well balanced DMA-based

	 * SPI transfer interface. There might still be moments when the Tx DMA

	 * channel is occasionally handled faster than the Rx DMA channel.

	 * That in its turn will eventually cause the SPI Rx FIFO overflow if

	 * SPI bus speed is high enough to fill the SPI Rx FIFO in before it's

	 * cleared by the Rx DMA channel. In order to fix the problem the Tx

	 * DMA activity is intentionally slowed down by limiting the SPI Tx

	 * FIFO depth with a value twice bigger than the Tx burst length

	 * calculated earlier by the dw_spi_dma_maxburst_init() method.

	 */

	dw_writel(dws, DW_SPI_DMARDLR, dws->rxburst - 1);

	dw_writel(dws, DW_SPI_DMATDLR, dws->fifo_len - dws->txburst);

	dw_writel(dws, DW_SPI_DMATDLR, dws->txburst);

	if (xfer->tx_buf)

		dma_ctrl |= SPI_DMA_TDMAE;