Unverified Commit 9b32c86e authored by Sean Anderson's avatar Sean Anderson Committed by Mark Brown
Browse files

spi: zynqmp-gqspi: Clean up fillgenfifo 



This function does a lot more work (assigning things multiple times,
masking unnecessarily, comparing to zero, using superfluous parentheses)
than it needs to. This makes it difficult to understand and modify.
Clean it up. No functional change intended.

Signed-off-by: default avatarSean Anderson <sean.anderson@linux.dev>
Link: https://patch.msgid.link/20250116224130.2684544-5-sean.anderson@linux.dev


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent d2ead60d

drivers/spi/spi-zynqmp-gqspi.c

+28 −50
Original line number Diff line number Diff line
@@ -82,7 +82,6 @@ 
#define GQSPI_GENFIFO_RX			0x00020000

#define GQSPI_GENFIFO_STRIPE			0x00040000

#define GQSPI_GENFIFO_POLL			0x00080000

#define GQSPI_GENFIFO_EXP_START			0x00000100

#define GQSPI_FIFO_CTRL_RST_RX_FIFO_MASK	0x00000004

#define GQSPI_FIFO_CTRL_RST_TX_FIFO_MASK	0x00000002

#define GQSPI_FIFO_CTRL_RST_GEN_FIFO_MASK	0x00000001
@@ -672,71 +671,50 @@ static void zynqmp_qspi_readrxfifo(struct zynqmp_qspi *xqspi, u32 size) 
static void zynqmp_qspi_fillgenfifo(struct zynqmp_qspi *xqspi, u8 nbits,

				    u32 genfifoentry)

{

	u32 transfer_len = 0;

	u32 transfer_len, tempcount, exponent;

	u8 imm_data;



	if (xqspi->txbuf) {

		genfifoentry &= ~GQSPI_GENFIFO_RX;

		genfifoentry |= GQSPI_GENFIFO_DATA_XFER;

		genfifoentry |= GQSPI_GENFIFO_TX;

		transfer_len = xqspi->bytes_to_transfer;

	} else if (xqspi->rxbuf) {

		genfifoentry &= ~GQSPI_GENFIFO_TX;

	genfifoentry |= GQSPI_GENFIFO_DATA_XFER;

	if (xqspi->rxbuf) {

		genfifoentry |= GQSPI_GENFIFO_RX;

		if (xqspi->mode == GQSPI_MODE_DMA)

			transfer_len = xqspi->dma_rx_bytes;

		else

			transfer_len = xqspi->bytes_to_receive;

	} else {

		/* Sending dummy circles here */

		genfifoentry &= ~(GQSPI_GENFIFO_TX | GQSPI_GENFIFO_RX);

		genfifoentry |= GQSPI_GENFIFO_DATA_XFER;

		transfer_len = xqspi->bytes_to_transfer;

	}



	if (xqspi->txbuf)

		genfifoentry |= GQSPI_GENFIFO_TX;



	genfifoentry |= zynqmp_qspi_selectspimode(xqspi, nbits);

	xqspi->genfifoentry = genfifoentry;

	dev_dbg(xqspi->dev, "genfifo %05x transfer_len %u\n",

		genfifoentry, transfer_len);



	if ((transfer_len) < GQSPI_GENFIFO_IMM_DATA_MASK) {

		genfifoentry &= ~GQSPI_GENFIFO_IMM_DATA_MASK;

		genfifoentry |= transfer_len;

		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, genfifoentry);

	} else {

		int tempcount = transfer_len;

		u32 exponent = 8;	/* 2^8 = 256 */

		u8 imm_data = tempcount & 0xFF;



		tempcount &= ~(tempcount & 0xFF);

		/* Immediate entry */

		if (tempcount != 0) {

	/* Exponent entries */

	imm_data = transfer_len;

	tempcount = transfer_len >> 8;

	exponent = 8;

	genfifoentry |= GQSPI_GENFIFO_EXP;

			while (tempcount != 0) {

				if (tempcount & GQSPI_GENFIFO_EXP_START) {

					genfifoentry &=

						~GQSPI_GENFIFO_IMM_DATA_MASK;

					genfifoentry |= exponent;

					zynqmp_gqspi_write(xqspi,

							   GQSPI_GEN_FIFO_OFST,

							   genfifoentry);

				}

				tempcount = tempcount >> 1;

	while (tempcount) {

		if (tempcount & 1)

			zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST,

					   genfifoentry | exponent);

		tempcount >>= 1;

		exponent++;

	}

		}

		if (imm_data != 0) {



	/* Immediate entry */

	genfifoentry &= ~GQSPI_GENFIFO_EXP;

			genfifoentry &= ~GQSPI_GENFIFO_IMM_DATA_MASK;

			genfifoentry |= (u8)(imm_data & 0xFF);

	if (imm_data)

		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST,

					   genfifoentry);

		}

	}

	if (xqspi->mode == GQSPI_MODE_IO && xqspi->rxbuf) {

				   genfifoentry | imm_data);



	/* Dummy generic FIFO entry */

		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, 0x0);

	}

	if (xqspi->mode == GQSPI_MODE_IO && xqspi->rxbuf)

		zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, 0);

}



/**