diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index 9d4b1cc..3758a0f 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -88,6 +88,14 @@ This enables support for the Freescale DSPI controller in master mode. VF610 platform uses the controller. +config SPI_ZYNQ_QSPI + tristate "Xilinx Zynq QSPI controller" + depends on ARCH_ZYNQ + depends on SPI_MEM + help + This enables support for the Zynq Quad SPI controller in master mode. + This controller only supports SPI memory interface. + endif endmenu diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index c5d2de7..75a89ef 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -11,3 +11,4 @@ obj-$(CONFIG_SPI_ATMEL_QUADSPI) += atmel-quadspi.o obj-$(CONFIG_DRIVER_SPI_OMAP3) += omap3_spi.o obj-$(CONFIG_DRIVER_SPI_DSPI) += dspi_spi.o +obj-$(CONFIG_SPI_ZYNQ_QSPI) += zynq_qspi.o diff --git a/drivers/spi/zynq_qspi.c b/drivers/spi/zynq_qspi.c new file mode 100644 index 0000000..d01e4a8 --- /dev/null +++ b/drivers/spi/zynq_qspi.c @@ -0,0 +1,612 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2019 Xilinx, Inc. + * + * Author: Naga Sureshkumar Relli + */ + +#include +#include +#include +#include +#include +#include +#include + +/* Register offset definitions */ +#define ZYNQ_QSPI_CONFIG_OFFSET 0x00 /* Configuration Register, RW */ +#define ZYNQ_QSPI_STATUS_OFFSET 0x04 /* Interrupt Status Register, RO */ +#define ZYNQ_QSPI_IEN_OFFSET 0x08 /* Interrupt Enable Register, WO */ +#define ZYNQ_QSPI_IDIS_OFFSET 0x0C /* Interrupt Disable Reg, WO */ +#define ZYNQ_QSPI_IMASK_OFFSET 0x10 /* Interrupt Enabled Mask Reg,RO */ +#define ZYNQ_QSPI_ENABLE_OFFSET 0x14 /* Enable/Disable Register, RW */ +#define ZYNQ_QSPI_DELAY_OFFSET 0x18 /* Delay Register, RW */ +#define ZYNQ_QSPI_TXD_00_00_OFFSET 0x1C /* Transmit 4-byte inst, WO */ +#define ZYNQ_QSPI_TXD_00_01_OFFSET 0x80 /* Transmit 1-byte inst, WO */ +#define ZYNQ_QSPI_TXD_00_10_OFFSET 0x84 /* Transmit 2-byte inst, WO */ +#define ZYNQ_QSPI_TXD_00_11_OFFSET 0x88 /* Transmit 3-byte inst, WO */ +#define ZYNQ_QSPI_RXD_OFFSET 0x20 /* Data Receive Register, RO */ +#define ZYNQ_QSPI_SIC_OFFSET 0x24 /* Slave Idle Count Register, RW */ +#define ZYNQ_QSPI_TX_THRESH_OFFSET 0x28 /* TX FIFO Watermark Reg, RW */ +#define ZYNQ_QSPI_RX_THRESH_OFFSET 0x2C /* RX FIFO Watermark Reg, RW */ +#define ZYNQ_QSPI_GPIO_OFFSET 0x30 /* GPIO Register, RW */ +#define ZYNQ_QSPI_LINEAR_CFG_OFFSET 0xA0 /* Linear Adapter Config Ref, RW */ +#define ZYNQ_QSPI_MOD_ID_OFFSET 0xFC /* Module ID Register, RO */ + +/* + * QSPI Configuration Register bit Masks + * + * This register contains various control bits that effect the operation + * of the QSPI controller + */ +#define ZYNQ_QSPI_CONFIG_IFMODE_MASK BIT(31) /* Flash Memory Interface */ +#define ZYNQ_QSPI_CONFIG_MANSRT_MASK BIT(16) /* Manual TX Start */ +#define ZYNQ_QSPI_CONFIG_MANSRTEN_MASK BIT(15) /* Enable Manual TX Mode */ +#define ZYNQ_QSPI_CONFIG_SSFORCE_MASK BIT(14) /* Manual Chip Select */ +#define ZYNQ_QSPI_CONFIG_BDRATE_MASK GENMASK(5, 3) /* Baud Rate Mask */ +#define ZYNQ_QSPI_CONFIG_CPHA_MASK BIT(2) /* Clock Phase Control */ +#define ZYNQ_QSPI_CONFIG_CPOL_MASK BIT(1) /* Clock Polarity Control */ +#define ZYNQ_QSPI_CONFIG_SSCTRL_MASK BIT(10) /* Slave Select Mask */ +#define ZYNQ_QSPI_CONFIG_FWIDTH_MASK GENMASK(7, 6) /* FIFO width */ +#define ZYNQ_QSPI_CONFIG_MSTREN_MASK BIT(0) /* Master Mode */ + +/* + * QSPI Configuration Register - Baud rate and slave select + * + * These are the values used in the calculation of baud rate divisor and + * setting the slave select. + */ +#define ZYNQ_QSPI_BAUD_DIV_MAX GENMASK(2, 0) /* Baud rate maximum */ +#define ZYNQ_QSPI_BAUD_DIV_SHIFT 3 /* Baud rate divisor shift in CR */ +#define ZYNQ_QSPI_SS_SHIFT 10 /* Slave Select field shift in CR */ + +/* + * QSPI Interrupt Registers bit Masks + * + * All the four interrupt registers (Status/Mask/Enable/Disable) have the same + * bit definitions. + */ +#define ZYNQ_QSPI_IXR_RX_OVERFLOW_MASK BIT(0) /* QSPI RX FIFO Overflow */ +#define ZYNQ_QSPI_IXR_TXNFULL_MASK BIT(2) /* QSPI TX FIFO Overflow */ +#define ZYNQ_QSPI_IXR_TXFULL_MASK BIT(3) /* QSPI TX FIFO is full */ +#define ZYNQ_QSPI_IXR_RXNEMTY_MASK BIT(4) /* QSPI RX FIFO Not Empty */ +#define ZYNQ_QSPI_IXR_RXF_FULL_MASK BIT(5) /* QSPI RX FIFO is full */ +#define ZYNQ_QSPI_IXR_TXF_UNDRFLOW_MASK BIT(6) /* QSPI TX FIFO Underflow */ +#define ZYNQ_QSPI_IXR_ALL_MASK (ZYNQ_QSPI_IXR_RX_OVERFLOW_MASK | \ + ZYNQ_QSPI_IXR_TXNFULL_MASK | \ + ZYNQ_QSPI_IXR_TXFULL_MASK | \ + ZYNQ_QSPI_IXR_RXNEMTY_MASK | \ + ZYNQ_QSPI_IXR_RXF_FULL_MASK | \ + ZYNQ_QSPI_IXR_TXF_UNDRFLOW_MASK) +#define ZYNQ_QSPI_IXR_RXTX_MASK (ZYNQ_QSPI_IXR_TXNFULL_MASK | \ + ZYNQ_QSPI_IXR_RXNEMTY_MASK) + +/* + * QSPI Enable Register bit Masks + * + * This register is used to enable or disable the QSPI controller + */ +#define ZYNQ_QSPI_ENABLE_ENABLE_MASK BIT(0) /* QSPI Enable Bit Mask */ + +/* + * QSPI Linear Configuration Register + * + * It is named Linear Configuration but it controls other modes when not in + * linear mode also. + */ +#define ZYNQ_QSPI_LCFG_TWO_MEM_MASK BIT(30) /* LQSPI Two memories Mask */ +#define ZYNQ_QSPI_LCFG_SEP_BUS_MASK BIT(29) /* LQSPI Separate bus Mask */ +#define ZYNQ_QSPI_LCFG_U_PAGE_MASK BIT(28) /* LQSPI Upper Page Mask */ + +#define ZYNQ_QSPI_LCFG_DUMMY_SHIFT 8 + +#define ZYNQ_QSPI_FAST_READ_QOUT_CODE 0x6B /* read instruction code */ +#define ZYNQ_QSPI_FIFO_DEPTH 63 /* FIFO depth in words */ +#define ZYNQ_QSPI_RX_THRESHOLD 32 /* Rx FIFO threshold level */ +#define ZYNQ_QSPI_TX_THRESHOLD 1 /* Tx FIFO threshold level */ + +/* + * The modebits configurable by the driver to make the SPI support different + * data formats + */ +#define ZYNQ_QSPI_MODEBITS (SPI_CPOL | SPI_CPHA) + +/** + * struct zynq_qspi - Defines qspi driver instance + * @regs: Virtual address of the QSPI controller registers + * @refclk: Pointer to the peripheral clock + * @pclk: Pointer to the APB clock + * @irq: IRQ number + * @txbuf: Pointer to the TX buffer + * @rxbuf: Pointer to the RX buffer + * @tx_bytes: Number of bytes left to transfer + * @rx_bytes: Number of bytes left to receive + * @data_completion: completion structure + */ +struct zynq_qspi { + struct spi_controller ctlr; + struct device_d *dev; + void __iomem *regs; + struct clk *refclk; + struct clk *pclk; + int tx_bytes; + int rx_bytes; + u8 *txbuf; + u8 *rxbuf; +}; + +/* + * Inline functions for the QSPI controller read/write + */ +static inline u32 zynq_qspi_read(struct zynq_qspi *xqspi, u32 offset) +{ + return readl(xqspi->regs + offset); +} + +static inline void zynq_qspi_write(struct zynq_qspi *xqspi, u32 offset, u32 val) +{ + writel(val, xqspi->regs + offset); +} + +/** + * zynq_qspi_init_hw - Initialize the hardware + * @xqspi: Pointer to the zynq_qspi structure + * + * The default settings of the QSPI controller's configurable parameters on + * reset are + * - Master mode + * - Baud rate divisor is set to 2 + * - Tx threshold set to 1l Rx threshold set to 32 + * - Flash memory interface mode enabled + * - Size of the word to be transferred as 8 bit + * This function performs the following actions + * - Disable and clear all the interrupts + * - Enable manual slave select + * - Enable manual start + * - Deselect all the chip select lines + * - Set the size of the word to be transferred as 32 bit + * - Set the little endian mode of TX FIFO and + * - Enable the QSPI controller + */ +static void zynq_qspi_init_hw(struct zynq_qspi *xqspi) +{ + u32 config_reg; + + zynq_qspi_write(xqspi, ZYNQ_QSPI_ENABLE_OFFSET, 0); + zynq_qspi_write(xqspi, ZYNQ_QSPI_IDIS_OFFSET, ZYNQ_QSPI_IXR_ALL_MASK); + + /* Disable linear mode as the boot loader may have used it */ + zynq_qspi_write(xqspi, ZYNQ_QSPI_LINEAR_CFG_OFFSET, 0); + + /* Clear the RX FIFO */ + while (zynq_qspi_read(xqspi, ZYNQ_QSPI_STATUS_OFFSET) & + ZYNQ_QSPI_IXR_RXNEMTY_MASK) + zynq_qspi_read(xqspi, ZYNQ_QSPI_RXD_OFFSET); + + zynq_qspi_write(xqspi, ZYNQ_QSPI_STATUS_OFFSET, ZYNQ_QSPI_IXR_ALL_MASK); + config_reg = zynq_qspi_read(xqspi, ZYNQ_QSPI_CONFIG_OFFSET); + config_reg &= ~(ZYNQ_QSPI_CONFIG_MSTREN_MASK | + ZYNQ_QSPI_CONFIG_CPOL_MASK | + ZYNQ_QSPI_CONFIG_CPHA_MASK | + ZYNQ_QSPI_CONFIG_BDRATE_MASK | + ZYNQ_QSPI_CONFIG_SSFORCE_MASK | + ZYNQ_QSPI_CONFIG_MANSRTEN_MASK | + ZYNQ_QSPI_CONFIG_MANSRT_MASK); + config_reg |= (ZYNQ_QSPI_CONFIG_MSTREN_MASK | + ZYNQ_QSPI_CONFIG_SSFORCE_MASK | + ZYNQ_QSPI_CONFIG_FWIDTH_MASK | + ZYNQ_QSPI_CONFIG_IFMODE_MASK); + zynq_qspi_write(xqspi, ZYNQ_QSPI_CONFIG_OFFSET, config_reg); + + zynq_qspi_write(xqspi, ZYNQ_QSPI_RX_THRESH_OFFSET, + ZYNQ_QSPI_RX_THRESHOLD); + zynq_qspi_write(xqspi, ZYNQ_QSPI_TX_THRESH_OFFSET, + ZYNQ_QSPI_TX_THRESHOLD); + + zynq_qspi_write(xqspi, ZYNQ_QSPI_ENABLE_OFFSET, + ZYNQ_QSPI_ENABLE_ENABLE_MASK); +} + +/** + * zynq_qspi_rxfifo_op - Read 1..4 bytes from RxFIFO to RX buffer + * @xqspi: Pointer to the zynq_qspi structure + * @size: Number of bytes to be read (1..4) + */ +static void zynq_qspi_rxfifo_op(struct zynq_qspi *xqspi, unsigned int size) +{ + u32 data; + + data = zynq_qspi_read(xqspi, ZYNQ_QSPI_RXD_OFFSET); + + if (xqspi->rxbuf) { + memcpy(xqspi->rxbuf, ((u8 *)&data) + 4 - size, size); + xqspi->rxbuf += size; + } + + xqspi->rx_bytes -= size; + if (xqspi->rx_bytes < 0) + xqspi->rx_bytes = 0; +} + +/** + * zynq_qspi_txfifo_op - Write 1..4 bytes from TX buffer to TxFIFO + * @xqspi: Pointer to the zynq_qspi structure + * @size: Number of bytes to be written (1..4) + */ +static void zynq_qspi_txfifo_op(struct zynq_qspi *xqspi, unsigned int size) +{ + static const unsigned int offset[4] = { + ZYNQ_QSPI_TXD_00_01_OFFSET, ZYNQ_QSPI_TXD_00_10_OFFSET, + ZYNQ_QSPI_TXD_00_11_OFFSET, ZYNQ_QSPI_TXD_00_00_OFFSET }; + u32 data; + + if (xqspi->txbuf) { + data = 0xffffffff; + memcpy(&data, xqspi->txbuf, size); + xqspi->txbuf += size; + } else { + data = 0; + } + + xqspi->tx_bytes -= size; + zynq_qspi_write(xqspi, offset[size - 1], data); +} + +/** + * zynq_qspi_chipselect - Select or deselect the chip select line + * @spi: Pointer to the spi_device structure + * @assert: 1 for select or 0 for deselect the chip select line + */ +static void zynq_qspi_chipselect(struct spi_device *spi, bool assert) +{ + struct spi_controller *ctrl = spi->master; + struct zynq_qspi *xqspi = spi_controller_get_devdata(ctrl); + u32 config_reg; + + config_reg = zynq_qspi_read(xqspi, ZYNQ_QSPI_CONFIG_OFFSET); + if (assert) { + /* Select the slave */ + config_reg &= ~ZYNQ_QSPI_CONFIG_SSCTRL_MASK; + config_reg |= (((~(BIT(spi->chip_select))) << + ZYNQ_QSPI_SS_SHIFT) & + ZYNQ_QSPI_CONFIG_SSCTRL_MASK); + } else { + config_reg |= ZYNQ_QSPI_CONFIG_SSCTRL_MASK; + } + + zynq_qspi_write(xqspi, ZYNQ_QSPI_CONFIG_OFFSET, config_reg); +} + +/** + * zynq_qspi_config_op - Configure QSPI controller for specified transfer + * @xqspi: Pointer to the zynq_qspi structure + * @qspi: Pointer to the spi_device structure + * + * Sets the operational mode of QSPI controller for the next QSPI transfer and + * sets the requested clock frequency. + * + * Return: 0 on success and -EINVAL on invalid input parameter + * + * Note: If the requested frequency is not an exact match with what can be + * obtained using the prescalar value, the driver sets the clock frequency which + * is lower than the requested frequency (maximum lower) for the transfer. If + * the requested frequency is higher or lower than that is supported by the QSPI + * controller the driver will set the highest or lowest frequency supported by + * controller. + */ +static int zynq_qspi_config_op(struct zynq_qspi *xqspi, struct spi_device *spi) +{ + u32 config_reg, baud_rate_val = 0; + + /* + * Set the clock frequency + * The baud rate divisor is not a direct mapping to the value written + * into the configuration register (config_reg[5:3]) + * i.e. 000 - divide by 2 + * 001 - divide by 4 + * ---------------- + * 111 - divide by 256 + */ + while ((baud_rate_val < ZYNQ_QSPI_BAUD_DIV_MAX) && + (clk_get_rate(xqspi->refclk) / (2 << baud_rate_val)) > + spi->max_speed_hz) + baud_rate_val++; + + config_reg = zynq_qspi_read(xqspi, ZYNQ_QSPI_CONFIG_OFFSET); + + /* Set the QSPI clock phase and clock polarity */ + config_reg &= (~ZYNQ_QSPI_CONFIG_CPHA_MASK) & + (~ZYNQ_QSPI_CONFIG_CPOL_MASK); + if (spi->mode & SPI_CPHA) + config_reg |= ZYNQ_QSPI_CONFIG_CPHA_MASK; + if (spi->mode & SPI_CPOL) + config_reg |= ZYNQ_QSPI_CONFIG_CPOL_MASK; + + config_reg &= ~ZYNQ_QSPI_CONFIG_BDRATE_MASK; + config_reg |= (baud_rate_val << ZYNQ_QSPI_BAUD_DIV_SHIFT); + zynq_qspi_write(xqspi, ZYNQ_QSPI_CONFIG_OFFSET, config_reg); + + return 0; +} + +static int zynq_qspi_setup_op(struct spi_device *spi) +{ + struct spi_controller *ctrl = spi->master; + struct zynq_qspi *xqspi = spi_controller_get_devdata(ctrl); + + zynq_qspi_write(xqspi, ZYNQ_QSPI_ENABLE_OFFSET, + ZYNQ_QSPI_ENABLE_ENABLE_MASK); + + return 0; +} + +/** + * zynq_qspi_write_op - Fills the TX FIFO with as many bytes as possible + * @xqspi: Pointer to the zynq_qspi structure + * @txcount: Maximum number of words to write + * @txempty: Indicates that TxFIFO is empty + */ +static void zynq_qspi_write_op(struct zynq_qspi *xqspi, int txcount, + bool txempty) +{ + int count, len, k; + + len = xqspi->tx_bytes; + if (len && len < sizeof(u32)) { + /* + * We must empty the TxFIFO between accesses to TXD0, + * TXD1, TXD2, TXD3. + */ + if (txempty) + zynq_qspi_txfifo_op(xqspi, len); + + return; + } + + count = len / sizeof(u32); + if (count > txcount) + count = txcount; + + if (xqspi->txbuf) { + u32 *buf = (u32 *)xqspi->txbuf; + for (k = 0; k < count; k++, buf++) + zynq_qspi_write(xqspi, ZYNQ_QSPI_TXD_00_00_OFFSET, *buf); + xqspi->txbuf += count * sizeof(u32); + } else { + for (k = 0; k < count; k++) + zynq_qspi_write(xqspi, ZYNQ_QSPI_TXD_00_00_OFFSET, 0); + } + + xqspi->tx_bytes -= count * sizeof(u32); +} + +/** + * zynq_qspi_read_op - Drains the RX FIFO by as many bytes as possible + * @xqspi: Pointer to the zynq_qspi structure + * @rxcount: Maximum number of words to read + */ +static void zynq_qspi_read_op(struct zynq_qspi *xqspi, int rxcount) +{ + int count, len, k; + + len = xqspi->rx_bytes - xqspi->tx_bytes; + count = len / sizeof(u32); + if (count > rxcount) + count = rxcount; + if (xqspi->rxbuf) { + u32 *buf = (u32 *)xqspi->rxbuf; + for (k = 0; k < count; k++, buf++) + *buf = zynq_qspi_read(xqspi, ZYNQ_QSPI_RXD_OFFSET); + xqspi->rxbuf += count * sizeof(u32); + } else { + for (k = 0; k < count; k++) + zynq_qspi_read(xqspi, ZYNQ_QSPI_RXD_OFFSET); + } + xqspi->rx_bytes -= count * sizeof(u32); + len -= count * sizeof(u32); + + if (len && len < 4 && count < rxcount) + zynq_qspi_rxfifo_op(xqspi, len); +} + +static int zynq_qspi_poll_irq(struct zynq_qspi *xqspi) +{ + u32 intr_status; + bool txempty; + int ret; + + for (;;) { + ret = readl_poll_timeout(xqspi->regs + ZYNQ_QSPI_STATUS_OFFSET, + intr_status, intr_status, + 100 * USEC_PER_MSEC); + if (ret) + return ret; + + zynq_qspi_write(xqspi, ZYNQ_QSPI_STATUS_OFFSET, intr_status); + + if ((intr_status & ZYNQ_QSPI_IXR_TXNFULL_MASK) || + (intr_status & ZYNQ_QSPI_IXR_RXNEMTY_MASK)) { + /* + * This bit is set when Tx FIFO has < THRESHOLD entries. + * We have the THRESHOLD value set to 1, + * so this bit indicates Tx FIFO is empty. + */ + txempty = !!(intr_status & ZYNQ_QSPI_IXR_TXNFULL_MASK); + /* Read out the data from the RX FIFO */ + zynq_qspi_read_op(xqspi, ZYNQ_QSPI_RX_THRESHOLD); + if (xqspi->tx_bytes) { + /* There is more data to send */ + zynq_qspi_write_op(xqspi, ZYNQ_QSPI_RX_THRESHOLD, + txempty); + } else if (!xqspi->rx_bytes){ + /* No more RX or TX bytes -> transfer done */ + return 0; + } + } + } +} + +/** + * zynq_qspi_exec_mem_op() - Initiates the QSPI transfer + * @mem: the SPI memory + * @op: the memory operation to execute + * + * Executes a memory operation. + * + * This function first selects the chip and starts the memory operation. + * + * Return: 0 in case of success, a negative error code otherwise. + */ +static int zynq_qspi_exec_mem_op(struct spi_mem *mem, + const struct spi_mem_op *op) +{ + struct zynq_qspi *xqspi = spi_controller_get_devdata(mem->spi->master); + int ret, i; + u8 *tmpbuf; + + dev_dbg(xqspi->dev, "cmd:%#x mode:%d.%d.%d.%d\n", + op->cmd.opcode, op->cmd.buswidth, op->addr.buswidth, + op->dummy.buswidth, op->data.buswidth); + + zynq_qspi_chipselect(mem->spi, true); + zynq_qspi_config_op(xqspi, mem->spi); + + if (op->cmd.opcode) { + xqspi->txbuf = (u8 *)&op->cmd.opcode; + xqspi->rxbuf = NULL; + xqspi->tx_bytes = sizeof(op->cmd.opcode); + xqspi->rx_bytes = sizeof(op->cmd.opcode); + zynq_qspi_write_op(xqspi, ZYNQ_QSPI_FIFO_DEPTH, true); + ret = zynq_qspi_poll_irq(xqspi); + if (ret) + return ret; + } + + if (op->addr.nbytes) { + for (i = 0; i < op->addr.nbytes; i++) { + xqspi->txbuf[i] = op->addr.val >> + (8 * (op->addr.nbytes - i - 1)); + } + + xqspi->rxbuf = NULL; + xqspi->tx_bytes = op->addr.nbytes; + xqspi->rx_bytes = op->addr.nbytes; + zynq_qspi_write_op(xqspi, ZYNQ_QSPI_FIFO_DEPTH, true); + ret = zynq_qspi_poll_irq(xqspi); + if (ret) + return ret; + } + + if (op->dummy.nbytes) { + tmpbuf = kzalloc(op->dummy.nbytes, GFP_KERNEL); + memset(tmpbuf, 0xff, op->dummy.nbytes); + xqspi->txbuf = tmpbuf; + xqspi->rxbuf = NULL; + xqspi->tx_bytes = op->dummy.nbytes; + xqspi->rx_bytes = op->dummy.nbytes; + zynq_qspi_write_op(xqspi, ZYNQ_QSPI_FIFO_DEPTH, true); + ret = zynq_qspi_poll_irq(xqspi); + kfree(tmpbuf); + if (ret) + return ret; + } + + if (op->data.nbytes) { + if (op->data.dir == SPI_MEM_DATA_OUT) { + xqspi->txbuf = (u8 *)op->data.buf.out; + xqspi->tx_bytes = op->data.nbytes; + xqspi->rxbuf = NULL; + xqspi->rx_bytes = op->data.nbytes; + } else { + xqspi->txbuf = NULL; + xqspi->rxbuf = (u8 *)op->data.buf.in; + xqspi->rx_bytes = op->data.nbytes; + xqspi->tx_bytes = op->data.nbytes; + } + + zynq_qspi_write_op(xqspi, ZYNQ_QSPI_FIFO_DEPTH, true); + ret = zynq_qspi_poll_irq(xqspi); + if (ret) + return ret; + } + + zynq_qspi_chipselect(mem->spi, false); + + return 0; +} + +static const struct spi_controller_mem_ops zynq_qspi_mem_ops = { + .exec_op = zynq_qspi_exec_mem_op, +}; + +static int zynq_qspi_probe(struct device_d *dev) +{ + struct device_node *np = dev->device_node; + struct spi_controller *ctlr; + struct zynq_qspi *xqspi; + struct resource *iores; + u32 num_cs; + int ret; + + xqspi = xzalloc(sizeof(*xqspi)); + + ctlr = &xqspi->ctlr; + xqspi->dev = dev; + + iores = dev_request_mem_resource(dev, 0); + if (IS_ERR(iores)) + return PTR_ERR(iores); + xqspi->regs = IOMEM(iores->start); + + xqspi->pclk = clk_get(dev, "pclk"); + if (IS_ERR_OR_NULL(xqspi->pclk)) { + dev_err(dev, "pclk clock not found.\n"); + return PTR_ERR(xqspi->pclk); + } + + xqspi->refclk = clk_get(dev, "ref_clk"); + if (IS_ERR_OR_NULL(xqspi->refclk)) { + dev_err(dev, "ref_clk clock not found.\n"); + return PTR_ERR(xqspi->refclk); + } + + ret = clk_enable(xqspi->pclk); + if (ret) { + dev_err(dev, "Unable to enable APB clock.\n"); + return ret; + } + + ret = clk_enable(xqspi->refclk); + if (ret) { + dev_err(dev, "Unable to enable device clock.\n"); + return ret; + } + + /* QSPI controller initializations */ + zynq_qspi_init_hw(xqspi); + + if (of_property_read_u32(np, "num-cs", &num_cs)) + ctlr->num_chipselect = 1; + else + ctlr->num_chipselect = num_cs; + + ctlr->dev = dev; + ctlr->mem_ops = &zynq_qspi_mem_ops; + ctlr->setup = zynq_qspi_setup_op; + + spi_controller_set_devdata(ctlr, xqspi); + + return spi_register_controller(ctlr); +} + +static const struct of_device_id zynq_qspi_of_match[] = { + { .compatible = "xlnx,zynq-qspi-1.0", }, + { /* end of table */ } +}; + +static struct driver_d zynq_qspi_driver = { + .name = "zynq-qspi", + .probe = zynq_qspi_probe, + .of_compatible = DRV_OF_COMPAT(zynq_qspi_of_match), +}; +device_platform_driver(zynq_qspi_driver);