[RFC PATCH 2/2] spi: Add support for Zynq Ultrascale+ MPSoC GQSPI controller
Ranjit Waghmode
ranjit.waghmode at xilinx.com
Wed May 20 00:27:51 PDT 2015
This patch adds support for GQSPI controller driver used by
Zynq Ultrascale+ MPSoC
Signed-off-by: Ranjit Waghmode <ranjit.waghmode at xilinx.com>
---
drivers/spi/Kconfig | 6 +
drivers/spi/Makefile | 1 +
drivers/spi/spi-zynqmp-gqspi.c | 1092 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 1099 insertions(+)
create mode 100644 drivers/spi/spi-zynqmp-gqspi.c
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 72b0590..4406a85 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -610,6 +610,12 @@ config SPI_XTENSA_XTFPGA
16 bit words in SPI mode 0, automatically asserting CS on transfer
start and deasserting on end.
+config SPI_ZYNQMP_GQSPI
+ tristate "Xilinx ZynqMP GQSPI controller"
+ depends on SPI_MASTER
+ help
+ Enables Xilinx GQSPI controller driver for Zynq UltraScale+ MPSoC.
+
config SPI_NUC900
tristate "Nuvoton NUC900 series SPI"
depends on ARCH_W90X900
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index d8cbf65..52db832 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -89,3 +89,4 @@ obj-$(CONFIG_SPI_TXX9) += spi-txx9.o
obj-$(CONFIG_SPI_XCOMM) += spi-xcomm.o
obj-$(CONFIG_SPI_XILINX) += spi-xilinx.o
obj-$(CONFIG_SPI_XTENSA_XTFPGA) += spi-xtensa-xtfpga.o
+obj-$(CONFIG_SPI_ZYNQMP_GQSPI) += spi-zynqmp-gqspi.o
diff --git a/drivers/spi/spi-zynqmp-gqspi.c b/drivers/spi/spi-zynqmp-gqspi.c
new file mode 100644
index 0000000..12ab885
--- /dev/null
+++ b/drivers/spi/spi-zynqmp-gqspi.c
@@ -0,0 +1,1092 @@
+/*
+ * Xilinx Zynq UltraScale+ MPSoC Quad-SPI (QSPI) controller driver
+ * (master mode only)
+ *
+ * Copyright (C) 2009 - 2015 Xilinx, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+#include <linux/spinlock.h>
+#include <linux/workqueue.h>
+
+/* Generic QSPI register offsets */
+#define GQSPI_CONFIG_OFST 0x00000100
+#define GQSPI_ISR_OFST 0x00000104
+#define GQSPI_IDR_OFST 0x0000010C
+#define GQSPI_IER_OFST 0x00000108
+#define GQSPI_IMASK_OFST 0x00000110
+#define GQSPI_EN_OFST 0x00000114
+#define GQSPI_TXD_OFST 0x0000011C
+#define GQSPI_RXD_OFST 0x00000120
+#define GQSPI_TX_THRESHOLD_OFST 0x00000128
+#define GQSPI_RX_THRESHOLD_OFST 0x0000012C
+#define GQSPI_LPBK_DLY_ADJ_OFST 0x00000138
+#define GQSPI_GEN_FIFO_OFST 0x00000140
+#define GQSPI_SEL_OFST 0x00000144
+#define GQSPI_GF_THRESHOLD_OFST 0x00000150
+#define GQSPI_FIFO_CTRL_OFST 0x0000014C
+#define GQSPI_QSPIDMA_DST_CTRL_OFST 0x0000080C
+#define GQSPI_QSPIDMA_DST_SIZE_OFST 0x00000804
+#define GQSPI_QSPIDMA_DST_STS_OFST 0x00000808
+#define GQSPI_QSPIDMA_DST_I_STS_OFST 0x00000814
+#define GQSPI_QSPIDMA_DST_I_EN_OFST 0x00000818
+#define GQSPI_QSPIDMA_DST_I_DIS_OFST 0x0000081C
+#define GQSPI_QSPIDMA_DST_I_MASK_OFST 0x00000820
+#define GQSPI_QSPIDMA_DST_ADDR_OFST 0x00000800
+#define GQSPI_QSPIDMA_DST_ADDR_MSB_OFST 0x00000828
+
+/* GQSPI register bit masks */
+#define GQSPI_SEL_MASK 0x00000001
+#define GQSPI_EN_MASK 0x00000001
+#define GQSPI_LPBK_DLY_ADJ_USE_LPBK_MASK 0x00000020
+#define GQSPI_ISR_WR_TO_CLR_MASK 0x00000002
+#define GQSPI_IDR_ALL_MASK 0x00000FBE
+#define GQSPI_CFG_MODE_EN_MASK 0xC0000000
+#define GQSPI_CFG_GEN_FIFO_START_MODE_MASK 0x20000000
+#define GQSPI_CFG_ENDIAN_MASK 0x04000000
+#define GQSPI_CFG_EN_POLL_TO_MASK 0x00100000
+#define GQSPI_CFG_WP_HOLD_MASK 0x00080000
+#define GQSPI_CFG_BAUD_RATE_DIV_MASK 0x00000038
+#define GQSPI_CFG_CLK_PHA_MASK 0x00000004
+#define GQSPI_CFG_CLK_POL_MASK 0x00000002
+#define GQSPI_CFG_START_GEN_FIFO_MASK 0x10000000
+#define GQSPI_GENFIFO_IMM_DATA_MASK 0x000000FF
+#define GQSPI_GENFIFO_DATA_XFER 0x00000100
+#define GQSPI_GENFIFO_EXP 0x00000200
+#define GQSPI_GENFIFO_MODE_SPI 0x00000400
+#define GQSPI_GENFIFO_MODE_DUALSPI 0x00000800
+#define GQSPI_GENFIFO_MODE_QUADSPI 0x00000C00
+#define GQSPI_GENFIFO_MODE_MASK 0x00000C00
+#define GQSPI_GENFIFO_CS_LOWER 0x00001000
+#define GQSPI_GENFIFO_CS_UPPER 0x00002000
+#define GQSPI_GENFIFO_BUS_LOWER 0x00004000
+#define GQSPI_GENFIFO_BUS_UPPER 0x00008000
+#define GQSPI_GENFIFO_BUS_BOTH 0x0000C000
+#define GQSPI_GENFIFO_BUS_MASK 0x0000C000
+#define GQSPI_GENFIFO_TX 0x00010000
+#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
+#define GQSPI_ISR_RXEMPTY_MASK 0x00000800
+#define GQSPI_ISR_GENFIFOFULL_MASK 0x00000400
+#define GQSPI_ISR_GENFIFONOT_FULL_MASK 0x00000200
+#define GQSPI_ISR_TXEMPTY_MASK 0x00000100
+#define GQSPI_ISR_GENFIFOEMPTY_MASK 0x00000080
+#define GQSPI_ISR_RXFULL_MASK 0x00000020
+#define GQSPI_ISR_RXNEMPTY_MASK 0x00000010
+#define GQSPI_ISR_TXFULL_MASK 0x00000008
+#define GQSPI_ISR_TXNOT_FULL_MASK 0x00000004
+#define GQSPI_ISR_POLL_TIME_EXPIRE_MASK 0x00000002
+#define GQSPI_IER_TXNOT_FULL_MASK 0x00000004
+#define GQSPI_IER_RXEMPTY_MASK 0x00000800
+#define GQSPI_IER_POLL_TIME_EXPIRE_MASK 0x00000002
+#define GQSPI_IER_RXNEMPTY_MASK 0x00000010
+#define GQSPI_IER_GENFIFOEMPTY_MASK 0x00000080
+#define GQSPI_IER_TXEMPTY_MASK 0x00000100
+#define GQSPI_QSPIDMA_DST_INTR_ALL_MASK 0x000000FE
+#define GQSPI_QSPIDMA_DST_STS_WTC 0x0000E000
+#define GQSPI_CFG_MODE_EN_DMA_MASK 0x80000000
+#define GQSPI_ISR_IDR_MASK 0x00000994
+#define GQSPI_QSPIDMA_DST_I_EN_DONE_MASK 0x00000002
+#define GQSPI_QSPIDMA_DST_I_STS_DONE_MASK 0x00000002
+#define GQSPI_IRQ_MASK 0x00000980
+
+#define GQSPI_CFG_BAUD_RATE_DIV_SHIFT 3
+#define GQSPI_GENFIFO_CS_SETUP 0x4
+#define GQSPI_GENFIFO_CS_HOLD 0x3
+#define GQSPI_TXD_DEPTH 64
+#define GQSPI_RX_FIFO_THRESHOLD 32
+#define GQSPI_RX_FIFO_FILL (GQSPI_RX_FIFO_THRESHOLD * 4)
+#define GQSPI_TX_FIFO_THRESHOLD_RESET_VAL 32
+#define GQSPI_TX_FIFO_FILL (GQSPI_TXD_DEPTH -\
+ GQSPI_TX_FIFO_THRESHOLD_RESET_VAL)
+#define GQSPI_GEN_FIFO_THRESHOLD_RESET_VAL 0X10
+#define GQSPI_QSPIDMA_DST_CTRL_RESET_VAL 0x803FFA00
+#define GQSPI_SELECT_FLASH_CS_LOWER 0x1
+#define GQSPI_SELECT_FLASH_CS_UPPER 0x2
+#define GQSPI_SELECT_FLASH_CS_BOTH 0x3
+#define GQSPI_SELECT_FLASH_BUS_LOWER 0x1
+#define GQSPI_SELECT_FLASH_BUS_UPPER 0x2
+#define GQSPI_SELECT_FLASH_BUS_BOTH 0x3
+#define GQSPI_BAUD_DIV_MAX 7 /* Baud rate divisor maximum */
+#define GQSPI_BAUD_DIV_SHIFT 2 /* Baud rate divisor shift */
+#define GQSPI_SELECT_MODE_SPI 0x1
+#define GQSPI_SELECT_MODE_DUALSPI 0x2
+#define GQSPI_SELECT_MODE_QUADSPI 0x4
+#define GQSPI_DMA_UNALIGN 0x3
+#define GQSPI_DEFAULT_NUM_CS 1 /* Default number of chip selects */
+
+enum mode_type {GQSPI_MODE_IO, GQSPI_MODE_DMA};
+
+/**
+ * struct zynqmp_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
+ * @dev: Pointer to struct device
+ * @txbuf: Pointer to the TX buffer
+ * @rxbuf: Pointer to the RX buffer
+ * @bytes_to_transfer: Number of bytes left to transfer
+ * @bytes_to_receive: Number of bytes left to receive
+ * @genfifocs: Used for chip select
+ * @genfifobus: Used to select the upper or lower bus
+ * @dma_rx_bytes: Remaining bytes to receive by DMA mode
+ * @dma_addr: DMA address after mapping the kernel buffer
+ * @genfifoentry Used for storing the genfifoentry instruction.
+ * @mode: Defines the mode in which QSPI is operating
+ */
+struct zynqmp_qspi {
+ void __iomem *regs;
+ struct clk *refclk;
+ struct clk *pclk;
+ int irq;
+ struct device *dev;
+ const void *txbuf;
+ void *rxbuf;
+ int bytes_to_transfer;
+ int bytes_to_receive;
+ u32 genfifocs;
+ u32 genfifobus;
+ u32 dma_rx_bytes;
+ dma_addr_t dma_addr;
+ u32 genfifoentry;
+ enum mode_type mode;
+};
+
+/**
+ * zynqmp_gqspi_read: For GQSPI controller read operation
+ * @xqspi: Pointer to the zynqmp_qspi structure
+ * @offset: Offset from where to read
+ */
+static u32 zynqmp_gqspi_read(struct zynqmp_qspi *xqspi, u32 offset)
+{
+ return readl_relaxed(xqspi->regs + offset);
+}
+
+/**
+ * zynqmp_gqspi_write: For GQSPI controller write operation
+ * @xqspi: Pointer to the zynqmp_qspi structure
+ * @offset: Offset where to write
+ * @val: Value to be written
+ */
+static inline void zynqmp_gqspi_write(struct zynqmp_qspi *xqspi, u32 offset,
+ u32 val)
+{
+ writel_relaxed(val, (xqspi->regs + offset));
+}
+
+/**
+ * zynqmp_gqspi_selectflash: For selection of flash
+ * @instanceptr: Pointer to the zynqmp_qspi structure
+ * @flashcs: For chip select
+ * @flashbus: To check which bus is selected- upper or lower
+ */
+static void zynqmp_gqspi_selectflash(struct zynqmp_qspi *instanceptr,
+ u8 flashcs, u8 flashbus)
+{
+ /*
+ * Bus and CS lines selected here will be updated in the instance and
+ * used for subsequent GENFIFO entries during transfer.
+ */
+ /* Choose slave select line */
+ switch (flashcs) {
+ case GQSPI_SELECT_FLASH_CS_BOTH:
+ instanceptr->genfifocs = GQSPI_GENFIFO_CS_LOWER |
+ GQSPI_GENFIFO_CS_UPPER;
+ break;
+ case GQSPI_SELECT_FLASH_CS_UPPER:
+ instanceptr->genfifocs = GQSPI_GENFIFO_CS_UPPER;
+ break;
+ case GQSPI_SELECT_FLASH_CS_LOWER:
+ default:
+ instanceptr->genfifocs = GQSPI_GENFIFO_CS_LOWER;
+ }
+
+ /* Choose bus */
+ switch (flashbus) {
+ case GQSPI_SELECT_FLASH_BUS_BOTH:
+ instanceptr->genfifobus = GQSPI_GENFIFO_BUS_LOWER |
+ GQSPI_GENFIFO_BUS_UPPER;
+ break;
+ case GQSPI_SELECT_FLASH_BUS_UPPER:
+ instanceptr->genfifobus = GQSPI_GENFIFO_BUS_UPPER;
+ break;
+ case GQSPI_SELECT_FLASH_BUS_LOWER:
+ default:
+ instanceptr->genfifobus = GQSPI_GENFIFO_BUS_LOWER;
+ }
+}
+
+/**
+ * zynqmp_qspi_init_hw: Initialize the hardware
+ * @xqspi: Pointer to the zynqmp_qspi structure
+ *
+ * The default settings of the QSPI controller's configurable parameters on
+ * reset are
+ * - Master mode
+ * - TX threshold set to 1
+ * - RX threshold set to 1
+ * - Flash memory interface mode enabled
+ * 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 little endian mode of TX FIFO and
+ * - Enable the QSPI controller
+ */
+static void zynqmp_qspi_init_hw(struct zynqmp_qspi *xqspi)
+{
+ u32 config_reg;
+
+ /* Select the GQSPI mode */
+ zynqmp_gqspi_write(xqspi, GQSPI_SEL_OFST, GQSPI_SEL_MASK);
+ /* Clear and disable interrupts */
+ zynqmp_gqspi_write(xqspi, GQSPI_ISR_OFST,
+ zynqmp_gqspi_read(xqspi, GQSPI_ISR_OFST) |
+ GQSPI_ISR_WR_TO_CLR_MASK);
+ /* Clear the DMA STS */
+ zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_I_STS_OFST,
+ zynqmp_gqspi_read(xqspi,
+ GQSPI_QSPIDMA_DST_I_STS_OFST));
+ zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_STS_OFST,
+ zynqmp_gqspi_read(xqspi,
+ GQSPI_QSPIDMA_DST_STS_OFST) |
+ GQSPI_QSPIDMA_DST_STS_WTC);
+ zynqmp_gqspi_write(xqspi, GQSPI_IDR_OFST, GQSPI_IDR_ALL_MASK);
+ zynqmp_gqspi_write(xqspi,
+ GQSPI_QSPIDMA_DST_I_DIS_OFST,
+ GQSPI_QSPIDMA_DST_INTR_ALL_MASK);
+ /* Disable the GQSPI */
+ zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0);
+ config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
+ config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
+ /* Manual start */
+ config_reg |= GQSPI_CFG_GEN_FIFO_START_MODE_MASK;
+ /* Little endian by default */
+ config_reg &= ~GQSPI_CFG_ENDIAN_MASK;
+ /* Disable poll time out */
+ config_reg &= ~GQSPI_CFG_EN_POLL_TO_MASK;
+ /* Set hold bit */
+ config_reg |= GQSPI_CFG_WP_HOLD_MASK;
+ /* Clear pre-scalar by default */
+ config_reg &= ~GQSPI_CFG_BAUD_RATE_DIV_MASK;
+ /* CPHA 0 */
+ config_reg &= ~GQSPI_CFG_CLK_PHA_MASK;
+ /* CPOL 0 */
+ config_reg &= ~GQSPI_CFG_CLK_POL_MASK;
+ zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
+
+ /* Clear the TX and RX FIFO */
+ zynqmp_gqspi_write(xqspi, GQSPI_FIFO_CTRL_OFST,
+ GQSPI_FIFO_CTRL_RST_RX_FIFO_MASK |
+ GQSPI_FIFO_CTRL_RST_TX_FIFO_MASK |
+ GQSPI_FIFO_CTRL_RST_GEN_FIFO_MASK);
+ /* Set by default to allow for high frequencies */
+ zynqmp_gqspi_write(xqspi, GQSPI_LPBK_DLY_ADJ_OFST,
+ zynqmp_gqspi_read(xqspi, GQSPI_LPBK_DLY_ADJ_OFST) |
+ GQSPI_LPBK_DLY_ADJ_USE_LPBK_MASK);
+ /* Reset thresholds */
+ zynqmp_gqspi_write(xqspi, GQSPI_TX_THRESHOLD_OFST,
+ GQSPI_TX_FIFO_THRESHOLD_RESET_VAL);
+ zynqmp_gqspi_write(xqspi, GQSPI_RX_THRESHOLD_OFST,
+ GQSPI_RX_FIFO_THRESHOLD);
+ zynqmp_gqspi_write(xqspi, GQSPI_GF_THRESHOLD_OFST,
+ GQSPI_GEN_FIFO_THRESHOLD_RESET_VAL);
+ zynqmp_gqspi_selectflash(xqspi,
+ GQSPI_SELECT_FLASH_CS_LOWER,
+ GQSPI_SELECT_FLASH_BUS_LOWER);
+ /* Initialize DMA */
+ zynqmp_gqspi_write(xqspi,
+ GQSPI_QSPIDMA_DST_CTRL_OFST,
+ GQSPI_QSPIDMA_DST_CTRL_RESET_VAL);
+
+ /* Enable the GQSPI */
+ zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, GQSPI_EN_MASK);
+}
+
+/**
+ * zynqmp_qspi_copy_read_data: Copy data to RX buffer
+ * @xqspi: Pointer to the zynqmp_qspi structure
+ * @data: The 32 bit variable where data is stored
+ * @size: Number of bytes to be copied from data to RX buffer
+ */
+static void zynqmp_qspi_copy_read_data(struct zynqmp_qspi *xqspi,
+ u32 data, u8 size)
+{
+ memcpy(xqspi->rxbuf, ((u8 *) &data), size);
+ xqspi->rxbuf += size;
+ xqspi->bytes_to_receive -= size;
+}
+
+/**
+ * zynqmp_prepare_transfer_hardware: Prepares hardware for transfer.
+ * @master: Pointer to the spi_master structure which provides
+ * information about the controller.
+ *
+ * This function enables SPI master controller.
+ *
+ * Return: Always 0
+ */
+static int zynqmp_prepare_transfer_hardware(struct spi_master *master)
+{
+ struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
+
+ clk_enable(xqspi->refclk);
+ clk_enable(xqspi->pclk);
+ zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, GQSPI_EN_MASK);
+ return 0;
+}
+
+/**
+ * zynqmp_unprepare_transfer_hardware: Relaxes hardware after transfer
+ * @master: Pointer to the spi_master structure which provides
+ * information about the controller.
+ *
+ * This function disables the SPI master controller.
+ *
+ * Return: Always 0
+ */
+static int zynqmp_unprepare_transfer_hardware(struct spi_master *master)
+{
+ struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
+
+ zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0);
+ clk_disable(xqspi->refclk);
+ clk_disable(xqspi->pclk);
+ return 0;
+}
+
+/**
+ * zynqmp_qspi_chipselect: Select or deselect the chip select line
+ * @qspi: Pointer to the spi_device structure
+ * @is_high: Select(0) or deselect (1) the chip select line
+ */
+static void zynqmp_qspi_chipselect(struct spi_device *qspi, bool is_high)
+{
+ struct zynqmp_qspi *xqspi = spi_master_get_devdata(qspi->master);
+ u32 genfifoentry = 0x0, statusreg, timeout;
+
+ genfifoentry |= GQSPI_GENFIFO_MODE_SPI;
+ genfifoentry |= xqspi->genfifobus;
+
+ if (!is_high) {
+ genfifoentry |= xqspi->genfifocs;
+ genfifoentry |= GQSPI_GENFIFO_CS_SETUP;
+ } else {
+ genfifoentry |= GQSPI_GENFIFO_CS_HOLD;
+ }
+
+ zynqmp_gqspi_write(xqspi, GQSPI_GEN_FIFO_OFST, genfifoentry);
+
+ if (is_high) {
+ /* Manually start the generic FIFO command */
+ zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
+ zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) |
+ GQSPI_CFG_START_GEN_FIFO_MASK);
+ timeout = 10000;
+ /* Wait until the generic FIFO command is empty */
+ do {
+ statusreg = zynqmp_gqspi_read(xqspi, GQSPI_ISR_OFST);
+ timeout--;
+ } while (!(statusreg &
+ GQSPI_ISR_GENFIFOEMPTY_MASK) &&
+ (statusreg & GQSPI_ISR_TXEMPTY_MASK) && timeout);
+ if (!timeout)
+ dev_err(xqspi->dev, "Chip select timed out\n");
+ }
+}
+
+/**
+ * zynqmp_qspi_setup_transfer: Configure QSPI controller for specified
+ * transfer
+ * @qspi: Pointer to the spi_device structure
+ * @transfer: Pointer to the spi_transfer structure which provides
+ * information about next transfer setup parameters
+ *
+ * Sets the operational mode of QSPI controller for the next QSPI transfer and
+ * sets the requested clock frequency.
+ *
+ * Return: Always 0
+ *
+ * Note:
+ * If the requested frequency is not an exact match with what can be
+ * obtained using the pre-scalar 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 zynqmp_qspi_setup_transfer(struct spi_device *qspi,
+ struct spi_transfer *transfer)
+{
+ struct zynqmp_qspi *xqspi = spi_master_get_devdata(qspi->master);
+ u32 config_reg, req_hz, baud_rate_val = 0;
+
+ if (transfer)
+ req_hz = transfer->speed_hz;
+ else
+ req_hz = qspi->max_speed_hz;
+
+ /* Set the clock frequency */
+ /* If req_hz == 0, default to lowest speed */
+ while ((baud_rate_val < GQSPI_BAUD_DIV_MAX) &&
+ (clk_get_rate(xqspi->refclk) /
+ (GQSPI_BAUD_DIV_SHIFT << baud_rate_val)) > req_hz)
+ baud_rate_val++;
+
+ config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
+
+ /* Set the QSPI clock phase and clock polarity */
+ config_reg &= (~GQSPI_CFG_CLK_PHA_MASK) & (~GQSPI_CFG_CLK_POL_MASK);
+
+ if (qspi->mode & SPI_CPHA)
+ config_reg |= GQSPI_CFG_CLK_PHA_MASK;
+ if (qspi->mode & SPI_CPOL)
+ config_reg |= GQSPI_CFG_CLK_POL_MASK;
+
+ config_reg &= ~GQSPI_CFG_BAUD_RATE_DIV_MASK;
+ config_reg |= (baud_rate_val << GQSPI_CFG_BAUD_RATE_DIV_SHIFT);
+ zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
+ return 0;
+}
+
+/**
+ * zynqmp_qspi_setup: Configure the QSPI controller
+ * @qspi: Pointer to the spi_device structure
+ *
+ * Sets the operational mode of QSPI controller for the next QSPI transfer,
+ * baud rate and divisor value to setup the requested qspi clock.
+ *
+ * Return: 0 Always
+ */
+static int zynqmp_qspi_setup(struct spi_device *qspi)
+{
+ if (qspi->master->busy)
+ return -EBUSY;
+ return zynqmp_qspi_setup_transfer(qspi, NULL);
+}
+
+/**
+ * zynqmp_qspi_filltxfifo: Fills the TX FIFO as long as there is room in
+ * the FIFO or the bytes required to be
+ * transmitted.
+ * @xqspi: Pointer to the zynqmp_qspi structure
+ * @size: Number of bytes to be copied from TX buffer to TX FIFO
+ */
+static void zynqmp_qspi_filltxfifo(struct zynqmp_qspi *xqspi, int size)
+{
+ u32 count = 0;
+
+ while ((xqspi->bytes_to_transfer > 0) && (count < size)) {
+ writel(*((u32 *) xqspi->txbuf), xqspi->regs + GQSPI_TXD_OFST);
+ if (xqspi->bytes_to_transfer >= 4) {
+ xqspi->txbuf += 4;
+ xqspi->bytes_to_transfer -= 4;
+ } else {
+ xqspi->txbuf += xqspi->bytes_to_transfer;
+ xqspi->bytes_to_transfer = 0;
+ }
+ count++;
+ }
+}
+
+/**
+ * zynqmp_qspi_readrxfifo: Fills the RX FIFO as long as there is room in
+ * the FIFO.
+ * @xqspi: Pointer to the zynqmp_qspi structure
+ * @size: Number of bytes to be copied from RX buffer to RX FIFO
+ */
+static void zynqmp_qspi_readrxfifo(struct zynqmp_qspi *xqspi, u32 size)
+{
+ int count = 0;
+ u32 data;
+
+ while ((count < size) && (xqspi->bytes_to_receive > 0)) {
+ if (xqspi->bytes_to_receive >= 4) {
+ (*(u32 *) xqspi->rxbuf) =
+ readl(xqspi->regs + GQSPI_RXD_OFST);
+ xqspi->rxbuf += 4;
+ xqspi->bytes_to_receive -= 4;
+ count += 4;
+ } else {
+ data = readl(xqspi->regs + GQSPI_RXD_OFST);
+ count += xqspi->bytes_to_receive;
+ zynqmp_qspi_copy_read_data(xqspi, data,
+ xqspi->bytes_to_receive);
+ xqspi->bytes_to_receive = 0;
+ }
+ }
+}
+
+/**
+ * zynqmp_process_dma_irq: Handler for DMA done interrupt of QSPI
+ * controller
+ * @xqspi: zynqmp_qspi instance pointer
+ *
+ * This function handles DMA interrupt only.
+ */
+static void zynqmp_process_dma_irq(struct zynqmp_qspi *xqspi)
+{
+ u32 config_reg, genfifoentry;
+
+ dma_unmap_single(xqspi->dev, xqspi->dma_addr,
+ xqspi->dma_rx_bytes, DMA_FROM_DEVICE);
+ xqspi->rxbuf += xqspi->dma_rx_bytes;
+ xqspi->bytes_to_receive -= xqspi->dma_rx_bytes;
+ xqspi->dma_rx_bytes = 0;
+
+ /* Disabling the DMA interrupts */
+ writel(GQSPI_QSPIDMA_DST_I_EN_DONE_MASK,
+ xqspi->regs + GQSPI_QSPIDMA_DST_I_DIS_OFST);
+
+ if (xqspi->bytes_to_receive > 0) {
+ /* Switch to IO mode,for remaining bytes to receive */
+ config_reg = readl(xqspi->regs + GQSPI_CONFIG_OFST);
+ config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
+ writel(config_reg, xqspi->regs + GQSPI_CONFIG_OFST);
+
+ /* Initiate the transfer of remaining bytes */
+ genfifoentry = xqspi->genfifoentry;
+ genfifoentry |= xqspi->bytes_to_receive;
+ writel(genfifoentry,
+ xqspi->regs + GQSPI_GEN_FIFO_OFST);
+
+ /* Dummy generic FIFO entry */
+ writel(0x0, xqspi->regs + GQSPI_GEN_FIFO_OFST);
+
+ /* Manual start */
+ zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
+ (readl(xqspi->regs + GQSPI_CONFIG_OFST) |
+ GQSPI_CFG_START_GEN_FIFO_MASK));
+
+ /* Enable the RX interrupts for IO mode */
+ zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
+ GQSPI_IER_GENFIFOEMPTY_MASK |
+ GQSPI_IER_RXNEMPTY_MASK |
+ GQSPI_IER_RXEMPTY_MASK);
+ }
+}
+
+/**
+ * zynqmp_qspi_irq: Interrupt service routine of the QSPI controller
+ * @irq: IRQ number
+ * @dev_id: Pointer to the xqspi structure
+ *
+ * This function handles TX empty only.
+ * On TX empty interrupt this function reads the received data from RX FIFO
+ * and fills the TX FIFO if there is any data remaining to be transferred.
+ *
+ * Return: IRQ_HANDLED when interrupt is handled
+ * IRQ_NONE otherwise.
+ */
+static irqreturn_t zynqmp_qspi_irq(int irq, void *dev_id)
+{
+ struct spi_master *master = dev_id;
+ struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
+ int ret = IRQ_NONE;
+ u32 status, mask, dma_status = 0;
+
+ status = readl(xqspi->regs + GQSPI_ISR_OFST);
+ writel(status, xqspi->regs + GQSPI_ISR_OFST);
+ mask = (status & ~(readl(xqspi->regs + GQSPI_IMASK_OFST)));
+
+ /* Read and clear DMA status */
+ if (xqspi->mode == GQSPI_MODE_DMA) {
+ dma_status = readl(xqspi->regs + GQSPI_QSPIDMA_DST_I_STS_OFST);
+ writel(dma_status, xqspi->regs + GQSPI_QSPIDMA_DST_I_STS_OFST);
+ }
+
+ if (mask & GQSPI_ISR_TXNOT_FULL_MASK) {
+ zynqmp_qspi_filltxfifo(xqspi, GQSPI_TX_FIFO_FILL);
+ ret = IRQ_HANDLED;
+ }
+
+ if (dma_status & GQSPI_QSPIDMA_DST_I_STS_DONE_MASK) {
+ zynqmp_process_dma_irq(xqspi);
+ ret = IRQ_HANDLED;
+ } else if (!(mask & GQSPI_IER_RXEMPTY_MASK) &&
+ (mask & GQSPI_IER_GENFIFOEMPTY_MASK)) {
+ zynqmp_qspi_readrxfifo(xqspi, GQSPI_RX_FIFO_FILL);
+ ret = IRQ_HANDLED;
+ }
+
+ if ((xqspi->bytes_to_receive == 0) && (xqspi->bytes_to_transfer == 0)
+ && ((status & GQSPI_IRQ_MASK) == GQSPI_IRQ_MASK)) {
+ writel(GQSPI_ISR_IDR_MASK, xqspi->regs + GQSPI_IDR_OFST);
+ spi_finalize_current_transfer(master);
+ ret = IRQ_HANDLED;
+ }
+ return ret;
+}
+
+/**
+ * zynqmp_qspi_selectspimode: Selects SPI mode - x1 or x2 or x4.
+ * @spimode: spimode - SPI or DUAL or QUAD.
+ * Return: Mask to set desired SPI mode in GENFIFO entry.
+ */
+static inline u32 zynqmp_qspi_selectspimode(u8 spimode)
+{
+ u32 mask;
+
+ switch (spimode) {
+ case GQSPI_SELECT_MODE_DUALSPI:
+ mask = GQSPI_GENFIFO_MODE_DUALSPI;
+ break;
+ case GQSPI_SELECT_MODE_QUADSPI:
+ mask = GQSPI_GENFIFO_MODE_QUADSPI;
+ break;
+ case GQSPI_SELECT_MODE_SPI:
+ default:
+ mask = GQSPI_GENFIFO_MODE_SPI;
+ }
+
+ return mask;
+}
+
+/**
+ * zynq_qspi_setuprxdma: This function sets up the RX DMA operation
+ * @xqspi: xqspi is a pointer to the GQSPI instance.
+ */
+static void zynq_qspi_setuprxdma(struct zynqmp_qspi *xqspi)
+{
+ u32 rx_bytes, rx_rem, config_reg;
+ dma_addr_t addr;
+ u64 dma_align = (u64)(uintptr_t)xqspi->rxbuf;
+
+ if ((xqspi->bytes_to_receive < 8) ||
+ ((dma_align & GQSPI_DMA_UNALIGN) != 0x0)) {
+ /* Setting to IO mode */
+ config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
+ config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
+ zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
+ xqspi->mode = GQSPI_MODE_IO;
+ xqspi->dma_rx_bytes = 0;
+ return;
+ }
+
+ rx_rem = xqspi->bytes_to_receive % 4;
+ rx_bytes = (xqspi->bytes_to_receive - rx_rem);
+
+ addr = dma_map_single(xqspi->dev, (void *)xqspi->rxbuf,
+ rx_bytes, DMA_FROM_DEVICE);
+ if (dma_mapping_error(xqspi->dev, addr))
+ dev_err(xqspi->dev, "ERR:rxdma:memory not mapped\n");
+
+ xqspi->dma_rx_bytes = rx_bytes;
+ xqspi->dma_addr = addr;
+ zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_ADDR_OFST,
+ (u32)(addr & 0xffffffff));
+ addr = ((addr >> 16) >> 16);
+ zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_ADDR_MSB_OFST,
+ ((u32)addr) & 0xfff);
+
+ /* Enabling the DMA mode */
+ config_reg = zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST);
+ config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
+ config_reg |= GQSPI_CFG_MODE_EN_DMA_MASK;
+ zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST, config_reg);
+
+ /* Switch to DMA mode */
+ xqspi->mode = GQSPI_MODE_DMA;
+
+ /* Write the number of bytes to transfer */
+ zynqmp_gqspi_write(xqspi, GQSPI_QSPIDMA_DST_SIZE_OFST, rx_bytes);
+}
+
+/**
+ * zynqmp_qspi_txrxsetup: This function checks the TX/RX buffers in
+ * the transfer and sets up the GENFIFO entries,
+ * TX FIFO as required.
+ * @xqspi: xqspi is a pointer to the GQSPI instance.
+ * @transfer: It is a pointer to the structure containing transfer data.
+ * @genfifoentry: genfifoentry is pointer to the variable in which
+ * GENFIFO mask is returned to calling function
+ */
+static void zynqmp_qspi_txrxsetup(struct zynqmp_qspi *xqspi,
+ struct spi_transfer *transfer,
+ u32 *genfifoentry)
+{
+ u32 config_reg;
+
+ /* Transmit */
+ if ((xqspi->txbuf != NULL) && (xqspi->rxbuf == NULL)) {
+ /* Setup data to be TXed */
+ *genfifoentry &= ~GQSPI_GENFIFO_RX;
+ *genfifoentry |= GQSPI_GENFIFO_DATA_XFER;
+ *genfifoentry |= GQSPI_GENFIFO_TX;
+ *genfifoentry |= zynqmp_qspi_selectspimode(transfer->tx_nbits);
+ xqspi->bytes_to_transfer = transfer->len;
+ if (xqspi->mode == GQSPI_MODE_DMA) {
+ config_reg = zynqmp_gqspi_read(xqspi,
+ GQSPI_CONFIG_OFST);
+ config_reg &= ~GQSPI_CFG_MODE_EN_MASK;
+ zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
+ config_reg);
+ xqspi->mode = GQSPI_MODE_IO;
+ }
+ zynqmp_qspi_filltxfifo(xqspi, GQSPI_TXD_DEPTH);
+ /* Discard RX data */
+ xqspi->bytes_to_receive = 0;
+ } else if ((xqspi->txbuf == NULL) && (xqspi->rxbuf != NULL)) {
+ /* Receive */
+
+ /* TX auto fill */
+ *genfifoentry &= ~GQSPI_GENFIFO_TX;
+ /* Setup RX */
+ *genfifoentry |= GQSPI_GENFIFO_DATA_XFER;
+ *genfifoentry |= GQSPI_GENFIFO_RX;
+ *genfifoentry |= zynqmp_qspi_selectspimode(transfer->rx_nbits);
+ xqspi->bytes_to_transfer = 0;
+ xqspi->bytes_to_receive = transfer->len;
+ zynq_qspi_setuprxdma(xqspi);
+ }
+}
+
+/**
+ * zynqmp_qspi_start_transfer: Initiates the QSPI transfer
+ * @master: Pointer to the spi_master structure which provides
+ * information about the controller.
+ * @qspi: Pointer to the spi_device structure
+ * @transfer: Pointer to the spi_transfer structure which provide information
+ * about next transfer parameters
+ *
+ * This function fills the TX FIFO, starts the QSPI transfer, and waits for the
+ * transfer to be completed.
+ *
+ * Return: Number of bytes transferred in the last transfer
+ */
+static int zynqmp_qspi_start_transfer(struct spi_master *master,
+ struct spi_device *qspi,
+ struct spi_transfer *transfer)
+{
+ struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
+ u32 genfifoentry = 0x0, transfer_len;
+
+ xqspi->txbuf = transfer->tx_buf;
+ xqspi->rxbuf = transfer->rx_buf;
+
+ genfifoentry |= xqspi->genfifocs;
+ genfifoentry |= xqspi->genfifobus;
+
+ zynqmp_qspi_txrxsetup(xqspi, transfer, &genfifoentry);
+
+ if (xqspi->mode == GQSPI_MODE_DMA)
+ transfer_len = xqspi->dma_rx_bytes;
+ else
+ transfer_len = transfer->len;
+
+ xqspi->genfifoentry = genfifoentry;
+ 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 */
+ 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;
+ exponent++;
+ }
+ }
+ if (imm_data != 0) {
+ genfifoentry &= ~GQSPI_GENFIFO_EXP;
+ genfifoentry &= ~GQSPI_GENFIFO_IMM_DATA_MASK;
+ genfifoentry |= (u8) (imm_data & 0xFF);
+ zynqmp_gqspi_write(xqspi,
+ GQSPI_GEN_FIFO_OFST, genfifoentry);
+ }
+ }
+
+ if ((xqspi->mode == GQSPI_MODE_IO) &&
+ (xqspi->rxbuf != NULL)) {
+ /* Dummy generic FIFO entry */
+ writel(0x0, xqspi->regs + GQSPI_GEN_FIFO_OFST);
+ }
+
+ /* Since we are using manual mode */
+ zynqmp_gqspi_write(xqspi, GQSPI_CONFIG_OFST,
+ zynqmp_gqspi_read(xqspi, GQSPI_CONFIG_OFST) |
+ GQSPI_CFG_START_GEN_FIFO_MASK);
+
+ if (xqspi->txbuf != NULL)
+ /* Enable interrupts for TX */
+ zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
+ GQSPI_IER_TXEMPTY_MASK |
+ GQSPI_IER_GENFIFOEMPTY_MASK |
+ GQSPI_IER_TXNOT_FULL_MASK);
+
+ if (xqspi->rxbuf != NULL) {
+ /* Enable interrupts for RX */
+ if (xqspi->mode == GQSPI_MODE_DMA) {
+ /* Enable DMA interrupts */
+ zynqmp_gqspi_write(xqspi,
+ GQSPI_QSPIDMA_DST_I_EN_OFST,
+ GQSPI_QSPIDMA_DST_I_EN_DONE_MASK);
+ } else {
+ zynqmp_gqspi_write(xqspi, GQSPI_IER_OFST,
+ GQSPI_IER_GENFIFOEMPTY_MASK |
+ GQSPI_IER_RXNEMPTY_MASK |
+ GQSPI_IER_RXEMPTY_MASK);
+ }
+ }
+
+ return transfer->len;
+}
+
+/**
+ * zynqmp_qspi_suspend: Suspend method for the QSPI driver
+ * @_dev: Address of the platform_device structure
+ *
+ * This function stops the QSPI driver queue and disables the QSPI controller
+ *
+ * Return: Always 0
+ */
+static int __maybe_unused zynqmp_qspi_suspend(struct device *dev)
+{
+ struct platform_device *pdev = container_of(dev,
+ struct platform_device,
+ dev);
+ struct spi_master *master = platform_get_drvdata(pdev);
+
+ spi_master_suspend(master);
+
+ zynqmp_unprepare_transfer_hardware(master);
+
+ return 0;
+}
+
+/**
+ * zynqmp_qspi_resume: Resume method for the QSPI driver
+ * @dev: Address of the platform_device structure
+ *
+ * The function starts the QSPI driver queue and initializes the QSPI
+ * controller
+ *
+ * Return: 0 on success and error value on error
+ */
+static int __maybe_unused zynqmp_qspi_resume(struct device *dev)
+{
+ struct platform_device *pdev = container_of(dev,
+ struct platform_device,
+ dev);
+ struct spi_master *master = platform_get_drvdata(pdev);
+ struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
+ int ret = 0;
+
+ ret = clk_enable(xqspi->pclk);
+ if (ret) {
+ dev_err(dev, "Cannot enable APB clock.\n");
+ return ret;
+ }
+
+ ret = clk_enable(xqspi->refclk);
+ if (ret) {
+ dev_err(dev, "Cannot enable device clock.\n");
+ clk_disable(xqspi->pclk);
+ return ret;
+ }
+
+ spi_master_resume(master);
+
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(zynqmp_qspi_dev_pm_ops, zynqmp_qspi_suspend,
+ zynqmp_qspi_resume);
+
+/**
+ * zynqmp_qspi_probe: Probe method for the QSPI driver
+ * @pdev: Pointer to the platform_device structure
+ *
+ * This function initializes the driver data structures and the hardware.
+ *
+ * Return: 0 on success and error value on failure
+ */
+static int zynqmp_qspi_probe(struct platform_device *pdev)
+{
+ int ret = 0;
+ struct spi_master *master;
+ struct zynqmp_qspi *xqspi;
+ struct resource *res;
+ struct device *dev = &pdev->dev;
+ u32 num_cs;
+
+ master = spi_alloc_master(&pdev->dev, sizeof(*xqspi));
+ if (!master)
+ return -ENOMEM;
+
+ xqspi = spi_master_get_devdata(master);
+ master->dev.of_node = pdev->dev.of_node;
+ platform_set_drvdata(pdev, master);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ xqspi->regs = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(xqspi->regs)) {
+ ret = PTR_ERR(xqspi->regs);
+ goto remove_master;
+ }
+
+ xqspi->dev = dev;
+ xqspi->pclk = devm_clk_get(&pdev->dev, "pclk");
+ if (IS_ERR(xqspi->pclk)) {
+ dev_err(dev, "pclk clock not found.\n");
+ ret = PTR_ERR(xqspi->pclk);
+ goto remove_master;
+ }
+
+ xqspi->refclk = devm_clk_get(&pdev->dev, "ref_clk");
+ if (IS_ERR(xqspi->refclk)) {
+ dev_err(dev, "ref_clk clock not found.\n");
+ ret = PTR_ERR(xqspi->refclk);
+ goto remove_master;
+ }
+
+ ret = clk_prepare_enable(xqspi->pclk);
+ if (ret) {
+ dev_err(dev, "Unable to enable APB clock.\n");
+ goto remove_master;
+ }
+
+ ret = clk_prepare_enable(xqspi->refclk);
+ if (ret) {
+ dev_err(dev, "Unable to enable device clock.\n");
+ goto clk_dis_pclk;
+ }
+
+ /* QSPI controller initializations */
+ zynqmp_qspi_init_hw(xqspi);
+
+ xqspi->irq = platform_get_irq(pdev, 0);
+ if (xqspi->irq <= 0) {
+ ret = -ENXIO;
+ dev_err(dev, "irq resource not found\n");
+ goto remove_master;
+ }
+ ret = devm_request_irq(&pdev->dev, xqspi->irq, zynqmp_qspi_irq,
+ 0, pdev->name, master);
+ if (ret != 0) {
+ ret = -ENXIO;
+ dev_err(dev, "request_irq failed\n");
+ goto remove_master;
+ }
+
+ ret = of_property_read_u32(pdev->dev.of_node, "num-cs", &num_cs);
+ if (ret < 0)
+ master->num_chipselect = GQSPI_DEFAULT_NUM_CS;
+ else
+ master->num_chipselect = num_cs;
+
+ master->setup = zynqmp_qspi_setup;
+ master->set_cs = zynqmp_qspi_chipselect;
+ master->transfer_one = zynqmp_qspi_start_transfer;
+ master->prepare_transfer_hardware = zynqmp_prepare_transfer_hardware;
+ master->unprepare_transfer_hardware =
+ zynqmp_unprepare_transfer_hardware;
+ master->max_speed_hz = clk_get_rate(xqspi->refclk) / 2;
+ master->bits_per_word_mask = SPI_BPW_MASK(8);
+ master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_RX_DUAL | SPI_RX_QUAD |
+ SPI_TX_DUAL | SPI_TX_QUAD;
+
+ if (master->dev.parent == NULL)
+ master->dev.parent = &master->dev;
+
+ ret = spi_register_master(master);
+ if (ret)
+ goto clk_dis_all;
+
+ return 0;
+
+clk_dis_all:
+ clk_disable_unprepare(xqspi->refclk);
+clk_dis_pclk:
+ clk_disable_unprepare(xqspi->pclk);
+remove_master:
+ spi_master_put(master);
+
+ return ret;
+}
+
+/**
+ * zynqmp_qspi_remove: Remove method for the QSPI driver
+ * @pdev: Pointer to the platform_device structure
+ *
+ * This function is called if a device is physically removed from the system or
+ * if the driver module is being unloaded. It frees all resources allocated to
+ * the device.
+ *
+ * Return: 0 Always
+ */
+static int zynqmp_qspi_remove(struct platform_device *pdev)
+{
+ struct spi_master *master = platform_get_drvdata(pdev);
+ struct zynqmp_qspi *xqspi = spi_master_get_devdata(master);
+
+ zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0);
+ clk_disable_unprepare(xqspi->refclk);
+ clk_disable_unprepare(xqspi->pclk);
+
+ spi_unregister_master(master);
+
+ return 0;
+}
+
+static const struct of_device_id zynqmp_qspi_of_match[] = {
+ { .compatible = "xlnx,zynqmp-qspi-1.0", },
+ { /* End of table */ }
+};
+
+MODULE_DEVICE_TABLE(of, zynqmp_qspi_of_match);
+
+static struct platform_driver zynqmp_qspi_driver = {
+ .probe = zynqmp_qspi_probe,
+ .remove = zynqmp_qspi_remove,
+ .driver = {
+ .name = "zynqmp-qspi",
+ .of_match_table = zynqmp_qspi_of_match,
+ .pm = &zynqmp_qspi_dev_pm_ops,
+ },
+};
+
+module_platform_driver(zynqmp_qspi_driver);
+
+MODULE_AUTHOR("Xilinx, Inc.");
+MODULE_DESCRIPTION("Xilinx Zynqmp QSPI driver");
+MODULE_LICENSE("GPL");
--
2.1.2
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