778 строки
23 KiB
C
778 строки
23 KiB
C
// SPDX-License-Identifier: GPL-2.0+
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/*
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* Copyright (C) 2019 Xilinx, Inc.
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*
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* Author: Naga Sureshkumar Relli <nagasure@xilinx.com>
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*/
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#include <linux/clk.h>
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#include <linux/delay.h>
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#include <linux/interrupt.h>
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#include <linux/io.h>
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#include <linux/module.h>
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#include <linux/of_irq.h>
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#include <linux/of_address.h>
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#include <linux/platform_device.h>
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#include <linux/spi/spi.h>
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#include <linux/workqueue.h>
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#include <linux/spi/spi-mem.h>
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/* Register offset definitions */
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#define ZYNQ_QSPI_CONFIG_OFFSET 0x00 /* Configuration Register, RW */
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#define ZYNQ_QSPI_STATUS_OFFSET 0x04 /* Interrupt Status Register, RO */
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#define ZYNQ_QSPI_IEN_OFFSET 0x08 /* Interrupt Enable Register, WO */
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#define ZYNQ_QSPI_IDIS_OFFSET 0x0C /* Interrupt Disable Reg, WO */
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#define ZYNQ_QSPI_IMASK_OFFSET 0x10 /* Interrupt Enabled Mask Reg,RO */
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#define ZYNQ_QSPI_ENABLE_OFFSET 0x14 /* Enable/Disable Register, RW */
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#define ZYNQ_QSPI_DELAY_OFFSET 0x18 /* Delay Register, RW */
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#define ZYNQ_QSPI_TXD_00_00_OFFSET 0x1C /* Transmit 4-byte inst, WO */
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#define ZYNQ_QSPI_TXD_00_01_OFFSET 0x80 /* Transmit 1-byte inst, WO */
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#define ZYNQ_QSPI_TXD_00_10_OFFSET 0x84 /* Transmit 2-byte inst, WO */
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#define ZYNQ_QSPI_TXD_00_11_OFFSET 0x88 /* Transmit 3-byte inst, WO */
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#define ZYNQ_QSPI_RXD_OFFSET 0x20 /* Data Receive Register, RO */
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#define ZYNQ_QSPI_SIC_OFFSET 0x24 /* Slave Idle Count Register, RW */
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#define ZYNQ_QSPI_TX_THRESH_OFFSET 0x28 /* TX FIFO Watermark Reg, RW */
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#define ZYNQ_QSPI_RX_THRESH_OFFSET 0x2C /* RX FIFO Watermark Reg, RW */
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#define ZYNQ_QSPI_GPIO_OFFSET 0x30 /* GPIO Register, RW */
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#define ZYNQ_QSPI_LINEAR_CFG_OFFSET 0xA0 /* Linear Adapter Config Ref, RW */
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#define ZYNQ_QSPI_MOD_ID_OFFSET 0xFC /* Module ID Register, RO */
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/*
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* QSPI Configuration Register bit Masks
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*
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* This register contains various control bits that effect the operation
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* of the QSPI controller
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*/
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#define ZYNQ_QSPI_CONFIG_IFMODE_MASK BIT(31) /* Flash Memory Interface */
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#define ZYNQ_QSPI_CONFIG_MANSRT_MASK BIT(16) /* Manual TX Start */
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#define ZYNQ_QSPI_CONFIG_MANSRTEN_MASK BIT(15) /* Enable Manual TX Mode */
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#define ZYNQ_QSPI_CONFIG_SSFORCE_MASK BIT(14) /* Manual Chip Select */
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#define ZYNQ_QSPI_CONFIG_BDRATE_MASK GENMASK(5, 3) /* Baud Rate Mask */
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#define ZYNQ_QSPI_CONFIG_CPHA_MASK BIT(2) /* Clock Phase Control */
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#define ZYNQ_QSPI_CONFIG_CPOL_MASK BIT(1) /* Clock Polarity Control */
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#define ZYNQ_QSPI_CONFIG_FWIDTH_MASK GENMASK(7, 6) /* FIFO width */
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#define ZYNQ_QSPI_CONFIG_MSTREN_MASK BIT(0) /* Master Mode */
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/*
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* QSPI Configuration Register - Baud rate and slave select
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*
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* These are the values used in the calculation of baud rate divisor and
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* setting the slave select.
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*/
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#define ZYNQ_QSPI_CONFIG_BAUD_DIV_MAX GENMASK(2, 0) /* Baud rate maximum */
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#define ZYNQ_QSPI_CONFIG_BAUD_DIV_SHIFT 3 /* Baud rate divisor shift */
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#define ZYNQ_QSPI_CONFIG_PCS BIT(10) /* Peripheral Chip Select */
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/*
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* QSPI Interrupt Registers bit Masks
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*
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* All the four interrupt registers (Status/Mask/Enable/Disable) have the same
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* bit definitions.
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*/
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#define ZYNQ_QSPI_IXR_RX_OVERFLOW_MASK BIT(0) /* QSPI RX FIFO Overflow */
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#define ZYNQ_QSPI_IXR_TXNFULL_MASK BIT(2) /* QSPI TX FIFO Overflow */
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#define ZYNQ_QSPI_IXR_TXFULL_MASK BIT(3) /* QSPI TX FIFO is full */
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#define ZYNQ_QSPI_IXR_RXNEMTY_MASK BIT(4) /* QSPI RX FIFO Not Empty */
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#define ZYNQ_QSPI_IXR_RXF_FULL_MASK BIT(5) /* QSPI RX FIFO is full */
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#define ZYNQ_QSPI_IXR_TXF_UNDRFLOW_MASK BIT(6) /* QSPI TX FIFO Underflow */
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#define ZYNQ_QSPI_IXR_ALL_MASK (ZYNQ_QSPI_IXR_RX_OVERFLOW_MASK | \
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ZYNQ_QSPI_IXR_TXNFULL_MASK | \
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ZYNQ_QSPI_IXR_TXFULL_MASK | \
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ZYNQ_QSPI_IXR_RXNEMTY_MASK | \
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ZYNQ_QSPI_IXR_RXF_FULL_MASK | \
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ZYNQ_QSPI_IXR_TXF_UNDRFLOW_MASK)
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#define ZYNQ_QSPI_IXR_RXTX_MASK (ZYNQ_QSPI_IXR_TXNFULL_MASK | \
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ZYNQ_QSPI_IXR_RXNEMTY_MASK)
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/*
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* QSPI Enable Register bit Masks
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*
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* This register is used to enable or disable the QSPI controller
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*/
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#define ZYNQ_QSPI_ENABLE_ENABLE_MASK BIT(0) /* QSPI Enable Bit Mask */
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/*
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* QSPI Linear Configuration Register
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*
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* It is named Linear Configuration but it controls other modes when not in
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* linear mode also.
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*/
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#define ZYNQ_QSPI_LCFG_TWO_MEM BIT(30) /* LQSPI Two memories */
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#define ZYNQ_QSPI_LCFG_SEP_BUS BIT(29) /* LQSPI Separate bus */
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#define ZYNQ_QSPI_LCFG_U_PAGE BIT(28) /* LQSPI Upper Page */
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#define ZYNQ_QSPI_LCFG_DUMMY_SHIFT 8
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#define ZYNQ_QSPI_FAST_READ_QOUT_CODE 0x6B /* read instruction code */
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#define ZYNQ_QSPI_FIFO_DEPTH 63 /* FIFO depth in words */
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#define ZYNQ_QSPI_RX_THRESHOLD 32 /* Rx FIFO threshold level */
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#define ZYNQ_QSPI_TX_THRESHOLD 1 /* Tx FIFO threshold level */
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/*
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* The modebits configurable by the driver to make the SPI support different
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* data formats
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*/
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#define ZYNQ_QSPI_MODEBITS (SPI_CPOL | SPI_CPHA)
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/* Maximum number of chip selects */
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#define ZYNQ_QSPI_MAX_NUM_CS 2
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/**
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* struct zynq_qspi - Defines qspi driver instance
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* @dev: Pointer to the this device's information
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* @regs: Virtual address of the QSPI controller registers
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* @refclk: Pointer to the peripheral clock
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* @pclk: Pointer to the APB clock
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* @irq: IRQ number
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* @txbuf: Pointer to the TX buffer
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* @rxbuf: Pointer to the RX buffer
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* @tx_bytes: Number of bytes left to transfer
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* @rx_bytes: Number of bytes left to receive
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* @data_completion: completion structure
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*/
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struct zynq_qspi {
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struct device *dev;
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void __iomem *regs;
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struct clk *refclk;
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struct clk *pclk;
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int irq;
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u8 *txbuf;
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u8 *rxbuf;
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int tx_bytes;
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int rx_bytes;
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struct completion data_completion;
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};
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/*
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* Inline functions for the QSPI controller read/write
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*/
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static inline u32 zynq_qspi_read(struct zynq_qspi *xqspi, u32 offset)
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{
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return readl_relaxed(xqspi->regs + offset);
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}
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static inline void zynq_qspi_write(struct zynq_qspi *xqspi, u32 offset,
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u32 val)
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{
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writel_relaxed(val, xqspi->regs + offset);
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}
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/**
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* zynq_qspi_init_hw - Initialize the hardware
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* @xqspi: Pointer to the zynq_qspi structure
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* @num_cs: Number of connected CS (to enable dual memories if needed)
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*
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* The default settings of the QSPI controller's configurable parameters on
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* reset are
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* - Master mode
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* - Baud rate divisor is set to 2
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* - Tx threshold set to 1l Rx threshold set to 32
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* - Flash memory interface mode enabled
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* - Size of the word to be transferred as 8 bit
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* This function performs the following actions
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* - Disable and clear all the interrupts
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* - Enable manual slave select
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* - Enable manual start
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* - Deselect all the chip select lines
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* - Set the size of the word to be transferred as 32 bit
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* - Set the little endian mode of TX FIFO and
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* - Enable the QSPI controller
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*/
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static void zynq_qspi_init_hw(struct zynq_qspi *xqspi, unsigned int num_cs)
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{
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u32 config_reg;
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zynq_qspi_write(xqspi, ZYNQ_QSPI_ENABLE_OFFSET, 0);
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zynq_qspi_write(xqspi, ZYNQ_QSPI_IDIS_OFFSET, ZYNQ_QSPI_IXR_ALL_MASK);
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/* Disable linear mode as the boot loader may have used it */
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config_reg = 0;
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/* At the same time, enable dual mode if more than 1 CS is available */
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if (num_cs > 1)
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config_reg |= ZYNQ_QSPI_LCFG_TWO_MEM;
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zynq_qspi_write(xqspi, ZYNQ_QSPI_LINEAR_CFG_OFFSET, config_reg);
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/* Clear the RX FIFO */
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while (zynq_qspi_read(xqspi, ZYNQ_QSPI_STATUS_OFFSET) &
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ZYNQ_QSPI_IXR_RXNEMTY_MASK)
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zynq_qspi_read(xqspi, ZYNQ_QSPI_RXD_OFFSET);
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zynq_qspi_write(xqspi, ZYNQ_QSPI_STATUS_OFFSET, ZYNQ_QSPI_IXR_ALL_MASK);
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config_reg = zynq_qspi_read(xqspi, ZYNQ_QSPI_CONFIG_OFFSET);
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config_reg &= ~(ZYNQ_QSPI_CONFIG_MSTREN_MASK |
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ZYNQ_QSPI_CONFIG_CPOL_MASK |
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ZYNQ_QSPI_CONFIG_CPHA_MASK |
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ZYNQ_QSPI_CONFIG_BDRATE_MASK |
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ZYNQ_QSPI_CONFIG_SSFORCE_MASK |
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ZYNQ_QSPI_CONFIG_MANSRTEN_MASK |
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ZYNQ_QSPI_CONFIG_MANSRT_MASK);
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config_reg |= (ZYNQ_QSPI_CONFIG_MSTREN_MASK |
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ZYNQ_QSPI_CONFIG_SSFORCE_MASK |
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ZYNQ_QSPI_CONFIG_FWIDTH_MASK |
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ZYNQ_QSPI_CONFIG_IFMODE_MASK);
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zynq_qspi_write(xqspi, ZYNQ_QSPI_CONFIG_OFFSET, config_reg);
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zynq_qspi_write(xqspi, ZYNQ_QSPI_RX_THRESH_OFFSET,
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ZYNQ_QSPI_RX_THRESHOLD);
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zynq_qspi_write(xqspi, ZYNQ_QSPI_TX_THRESH_OFFSET,
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ZYNQ_QSPI_TX_THRESHOLD);
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zynq_qspi_write(xqspi, ZYNQ_QSPI_ENABLE_OFFSET,
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ZYNQ_QSPI_ENABLE_ENABLE_MASK);
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}
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static bool zynq_qspi_supports_op(struct spi_mem *mem,
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const struct spi_mem_op *op)
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{
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if (!spi_mem_default_supports_op(mem, op))
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return false;
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/*
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* The number of address bytes should be equal to or less than 3 bytes.
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*/
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if (op->addr.nbytes > 3)
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return false;
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return true;
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}
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/**
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* zynq_qspi_rxfifo_op - Read 1..4 bytes from RxFIFO to RX buffer
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* @xqspi: Pointer to the zynq_qspi structure
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* @size: Number of bytes to be read (1..4)
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*/
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static void zynq_qspi_rxfifo_op(struct zynq_qspi *xqspi, unsigned int size)
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{
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u32 data;
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data = zynq_qspi_read(xqspi, ZYNQ_QSPI_RXD_OFFSET);
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if (xqspi->rxbuf) {
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memcpy(xqspi->rxbuf, ((u8 *)&data) + 4 - size, size);
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xqspi->rxbuf += size;
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}
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xqspi->rx_bytes -= size;
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if (xqspi->rx_bytes < 0)
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xqspi->rx_bytes = 0;
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}
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/**
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* zynq_qspi_txfifo_op - Write 1..4 bytes from TX buffer to TxFIFO
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* @xqspi: Pointer to the zynq_qspi structure
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* @size: Number of bytes to be written (1..4)
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*/
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static void zynq_qspi_txfifo_op(struct zynq_qspi *xqspi, unsigned int size)
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{
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static const unsigned int offset[4] = {
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ZYNQ_QSPI_TXD_00_01_OFFSET, ZYNQ_QSPI_TXD_00_10_OFFSET,
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ZYNQ_QSPI_TXD_00_11_OFFSET, ZYNQ_QSPI_TXD_00_00_OFFSET };
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u32 data;
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if (xqspi->txbuf) {
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data = 0xffffffff;
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memcpy(&data, xqspi->txbuf, size);
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xqspi->txbuf += size;
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} else {
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data = 0;
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}
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xqspi->tx_bytes -= size;
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zynq_qspi_write(xqspi, offset[size - 1], data);
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}
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/**
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* zynq_qspi_chipselect - Select or deselect the chip select line
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* @spi: Pointer to the spi_device structure
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* @assert: 1 for select or 0 for deselect the chip select line
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*/
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static void zynq_qspi_chipselect(struct spi_device *spi, bool assert)
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{
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struct spi_controller *ctlr = spi->master;
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struct zynq_qspi *xqspi = spi_controller_get_devdata(ctlr);
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u32 config_reg;
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/* Select the lower (CS0) or upper (CS1) memory */
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if (ctlr->num_chipselect > 1) {
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config_reg = zynq_qspi_read(xqspi, ZYNQ_QSPI_LINEAR_CFG_OFFSET);
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if (!spi_get_chipselect(spi, 0))
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config_reg &= ~ZYNQ_QSPI_LCFG_U_PAGE;
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else
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config_reg |= ZYNQ_QSPI_LCFG_U_PAGE;
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zynq_qspi_write(xqspi, ZYNQ_QSPI_LINEAR_CFG_OFFSET, config_reg);
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}
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/* Ground the line to assert the CS */
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config_reg = zynq_qspi_read(xqspi, ZYNQ_QSPI_CONFIG_OFFSET);
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if (assert)
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config_reg &= ~ZYNQ_QSPI_CONFIG_PCS;
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else
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config_reg |= ZYNQ_QSPI_CONFIG_PCS;
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zynq_qspi_write(xqspi, ZYNQ_QSPI_CONFIG_OFFSET, config_reg);
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}
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/**
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* zynq_qspi_config_op - Configure QSPI controller for specified transfer
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* @xqspi: Pointer to the zynq_qspi structure
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* @spi: Pointer to the spi_device structure
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*
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* Sets the operational mode of QSPI controller for the next QSPI transfer and
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* sets the requested clock frequency.
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*
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* Return: 0 on success and -EINVAL on invalid input parameter
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*
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* Note: If the requested frequency is not an exact match with what can be
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* obtained using the prescalar value, the driver sets the clock frequency which
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* is lower than the requested frequency (maximum lower) for the transfer. If
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* the requested frequency is higher or lower than that is supported by the QSPI
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* controller the driver will set the highest or lowest frequency supported by
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* controller.
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*/
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static int zynq_qspi_config_op(struct zynq_qspi *xqspi, struct spi_device *spi)
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{
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u32 config_reg, baud_rate_val = 0;
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/*
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* Set the clock frequency
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* The baud rate divisor is not a direct mapping to the value written
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* into the configuration register (config_reg[5:3])
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* i.e. 000 - divide by 2
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* 001 - divide by 4
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* ----------------
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* 111 - divide by 256
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*/
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while ((baud_rate_val < ZYNQ_QSPI_CONFIG_BAUD_DIV_MAX) &&
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(clk_get_rate(xqspi->refclk) / (2 << baud_rate_val)) >
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spi->max_speed_hz)
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baud_rate_val++;
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config_reg = zynq_qspi_read(xqspi, ZYNQ_QSPI_CONFIG_OFFSET);
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/* Set the QSPI clock phase and clock polarity */
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config_reg &= (~ZYNQ_QSPI_CONFIG_CPHA_MASK) &
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(~ZYNQ_QSPI_CONFIG_CPOL_MASK);
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if (spi->mode & SPI_CPHA)
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config_reg |= ZYNQ_QSPI_CONFIG_CPHA_MASK;
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if (spi->mode & SPI_CPOL)
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config_reg |= ZYNQ_QSPI_CONFIG_CPOL_MASK;
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config_reg &= ~ZYNQ_QSPI_CONFIG_BDRATE_MASK;
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config_reg |= (baud_rate_val << ZYNQ_QSPI_CONFIG_BAUD_DIV_SHIFT);
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zynq_qspi_write(xqspi, ZYNQ_QSPI_CONFIG_OFFSET, config_reg);
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return 0;
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}
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/**
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* zynq_qspi_setup_op - Configure the QSPI controller
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* @spi: Pointer to the spi_device structure
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*
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* Sets the operational mode of QSPI controller for the next QSPI transfer, baud
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* rate and divisor value to setup the requested qspi clock.
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*
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* Return: 0 on success and error value on failure
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*/
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static int zynq_qspi_setup_op(struct spi_device *spi)
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{
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struct spi_controller *ctlr = spi->master;
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struct zynq_qspi *qspi = spi_controller_get_devdata(ctlr);
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if (ctlr->busy)
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return -EBUSY;
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clk_enable(qspi->refclk);
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clk_enable(qspi->pclk);
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zynq_qspi_write(qspi, ZYNQ_QSPI_ENABLE_OFFSET,
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ZYNQ_QSPI_ENABLE_ENABLE_MASK);
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return 0;
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}
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/**
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* zynq_qspi_write_op - Fills the TX FIFO with as many bytes as possible
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* @xqspi: Pointer to the zynq_qspi structure
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* @txcount: Maximum number of words to write
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* @txempty: Indicates that TxFIFO is empty
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*/
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static void zynq_qspi_write_op(struct zynq_qspi *xqspi, int txcount,
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bool txempty)
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{
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int count, len, k;
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len = xqspi->tx_bytes;
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if (len && len < 4) {
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/*
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* We must empty the TxFIFO between accesses to TXD0,
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* TXD1, TXD2, TXD3.
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*/
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if (txempty)
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zynq_qspi_txfifo_op(xqspi, len);
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return;
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}
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count = len / 4;
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if (count > txcount)
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count = txcount;
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if (xqspi->txbuf) {
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iowrite32_rep(xqspi->regs + ZYNQ_QSPI_TXD_00_00_OFFSET,
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xqspi->txbuf, count);
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xqspi->txbuf += count * 4;
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} else {
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for (k = 0; k < count; k++)
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writel_relaxed(0, xqspi->regs +
|
|
ZYNQ_QSPI_TXD_00_00_OFFSET);
|
|
}
|
|
|
|
xqspi->tx_bytes -= count * 4;
|
|
}
|
|
|
|
/**
|
|
* 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 / 4;
|
|
if (count > rxcount)
|
|
count = rxcount;
|
|
if (xqspi->rxbuf) {
|
|
ioread32_rep(xqspi->regs + ZYNQ_QSPI_RXD_OFFSET,
|
|
xqspi->rxbuf, count);
|
|
xqspi->rxbuf += count * 4;
|
|
} else {
|
|
for (k = 0; k < count; k++)
|
|
readl_relaxed(xqspi->regs + ZYNQ_QSPI_RXD_OFFSET);
|
|
}
|
|
xqspi->rx_bytes -= count * 4;
|
|
len -= count * 4;
|
|
|
|
if (len && len < 4 && count < rxcount)
|
|
zynq_qspi_rxfifo_op(xqspi, len);
|
|
}
|
|
|
|
/**
|
|
* zynq_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 zynq_qspi_irq(int irq, void *dev_id)
|
|
{
|
|
u32 intr_status;
|
|
bool txempty;
|
|
struct zynq_qspi *xqspi = (struct zynq_qspi *)dev_id;
|
|
|
|
intr_status = zynq_qspi_read(xqspi, ZYNQ_QSPI_STATUS_OFFSET);
|
|
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 transfer and receive is completed then only send
|
|
* complete signal.
|
|
*/
|
|
if (!xqspi->rx_bytes) {
|
|
zynq_qspi_write(xqspi,
|
|
ZYNQ_QSPI_IDIS_OFFSET,
|
|
ZYNQ_QSPI_IXR_RXTX_MASK);
|
|
complete(&xqspi->data_completion);
|
|
}
|
|
}
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
return IRQ_NONE;
|
|
}
|
|
|
|
/**
|
|
* 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 err = 0, 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) {
|
|
reinit_completion(&xqspi->data_completion);
|
|
xqspi->txbuf = (u8 *)&op->cmd.opcode;
|
|
xqspi->rxbuf = NULL;
|
|
xqspi->tx_bytes = op->cmd.nbytes;
|
|
xqspi->rx_bytes = op->cmd.nbytes;
|
|
zynq_qspi_write_op(xqspi, ZYNQ_QSPI_FIFO_DEPTH, true);
|
|
zynq_qspi_write(xqspi, ZYNQ_QSPI_IEN_OFFSET,
|
|
ZYNQ_QSPI_IXR_RXTX_MASK);
|
|
if (!wait_for_completion_timeout(&xqspi->data_completion,
|
|
msecs_to_jiffies(1000)))
|
|
err = -ETIMEDOUT;
|
|
}
|
|
|
|
if (op->addr.nbytes) {
|
|
for (i = 0; i < op->addr.nbytes; i++) {
|
|
xqspi->txbuf[i] = op->addr.val >>
|
|
(8 * (op->addr.nbytes - i - 1));
|
|
}
|
|
|
|
reinit_completion(&xqspi->data_completion);
|
|
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);
|
|
zynq_qspi_write(xqspi, ZYNQ_QSPI_IEN_OFFSET,
|
|
ZYNQ_QSPI_IXR_RXTX_MASK);
|
|
if (!wait_for_completion_timeout(&xqspi->data_completion,
|
|
msecs_to_jiffies(1000)))
|
|
err = -ETIMEDOUT;
|
|
}
|
|
|
|
if (op->dummy.nbytes) {
|
|
tmpbuf = kzalloc(op->dummy.nbytes, GFP_KERNEL);
|
|
if (!tmpbuf)
|
|
return -ENOMEM;
|
|
|
|
memset(tmpbuf, 0xff, op->dummy.nbytes);
|
|
reinit_completion(&xqspi->data_completion);
|
|
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);
|
|
zynq_qspi_write(xqspi, ZYNQ_QSPI_IEN_OFFSET,
|
|
ZYNQ_QSPI_IXR_RXTX_MASK);
|
|
if (!wait_for_completion_timeout(&xqspi->data_completion,
|
|
msecs_to_jiffies(1000)))
|
|
err = -ETIMEDOUT;
|
|
|
|
kfree(tmpbuf);
|
|
}
|
|
|
|
if (op->data.nbytes) {
|
|
reinit_completion(&xqspi->data_completion);
|
|
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);
|
|
zynq_qspi_write(xqspi, ZYNQ_QSPI_IEN_OFFSET,
|
|
ZYNQ_QSPI_IXR_RXTX_MASK);
|
|
if (!wait_for_completion_timeout(&xqspi->data_completion,
|
|
msecs_to_jiffies(1000)))
|
|
err = -ETIMEDOUT;
|
|
}
|
|
zynq_qspi_chipselect(mem->spi, false);
|
|
|
|
return err;
|
|
}
|
|
|
|
static const struct spi_controller_mem_ops zynq_qspi_mem_ops = {
|
|
.supports_op = zynq_qspi_supports_op,
|
|
.exec_op = zynq_qspi_exec_mem_op,
|
|
};
|
|
|
|
/**
|
|
* zynq_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 zynq_qspi_probe(struct platform_device *pdev)
|
|
{
|
|
int ret = 0;
|
|
struct spi_controller *ctlr;
|
|
struct device *dev = &pdev->dev;
|
|
struct device_node *np = dev->of_node;
|
|
struct zynq_qspi *xqspi;
|
|
u32 num_cs;
|
|
|
|
ctlr = spi_alloc_master(&pdev->dev, sizeof(*xqspi));
|
|
if (!ctlr)
|
|
return -ENOMEM;
|
|
|
|
xqspi = spi_controller_get_devdata(ctlr);
|
|
xqspi->dev = dev;
|
|
platform_set_drvdata(pdev, xqspi);
|
|
xqspi->regs = devm_platform_ioremap_resource(pdev, 0);
|
|
if (IS_ERR(xqspi->regs)) {
|
|
ret = PTR_ERR(xqspi->regs);
|
|
goto remove_master;
|
|
}
|
|
|
|
xqspi->pclk = devm_clk_get(&pdev->dev, "pclk");
|
|
if (IS_ERR(xqspi->pclk)) {
|
|
dev_err(&pdev->dev, "pclk clock not found.\n");
|
|
ret = PTR_ERR(xqspi->pclk);
|
|
goto remove_master;
|
|
}
|
|
|
|
init_completion(&xqspi->data_completion);
|
|
|
|
xqspi->refclk = devm_clk_get(&pdev->dev, "ref_clk");
|
|
if (IS_ERR(xqspi->refclk)) {
|
|
dev_err(&pdev->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(&pdev->dev, "Unable to enable APB clock.\n");
|
|
goto remove_master;
|
|
}
|
|
|
|
ret = clk_prepare_enable(xqspi->refclk);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "Unable to enable device clock.\n");
|
|
goto clk_dis_pclk;
|
|
}
|
|
|
|
xqspi->irq = platform_get_irq(pdev, 0);
|
|
if (xqspi->irq < 0) {
|
|
ret = xqspi->irq;
|
|
goto clk_dis_all;
|
|
}
|
|
ret = devm_request_irq(&pdev->dev, xqspi->irq, zynq_qspi_irq,
|
|
0, pdev->name, xqspi);
|
|
if (ret != 0) {
|
|
ret = -ENXIO;
|
|
dev_err(&pdev->dev, "request_irq failed\n");
|
|
goto clk_dis_all;
|
|
}
|
|
|
|
ret = of_property_read_u32(np, "num-cs",
|
|
&num_cs);
|
|
if (ret < 0) {
|
|
ctlr->num_chipselect = 1;
|
|
} else if (num_cs > ZYNQ_QSPI_MAX_NUM_CS) {
|
|
ret = -EINVAL;
|
|
dev_err(&pdev->dev, "only 2 chip selects are available\n");
|
|
goto clk_dis_all;
|
|
} else {
|
|
ctlr->num_chipselect = num_cs;
|
|
}
|
|
|
|
ctlr->mode_bits = SPI_RX_DUAL | SPI_RX_QUAD |
|
|
SPI_TX_DUAL | SPI_TX_QUAD;
|
|
ctlr->mem_ops = &zynq_qspi_mem_ops;
|
|
ctlr->setup = zynq_qspi_setup_op;
|
|
ctlr->max_speed_hz = clk_get_rate(xqspi->refclk) / 2;
|
|
ctlr->dev.of_node = np;
|
|
|
|
/* QSPI controller initializations */
|
|
zynq_qspi_init_hw(xqspi, ctlr->num_chipselect);
|
|
|
|
ret = devm_spi_register_controller(&pdev->dev, ctlr);
|
|
if (ret) {
|
|
dev_err(&pdev->dev, "spi_register_master failed\n");
|
|
goto clk_dis_all;
|
|
}
|
|
|
|
return ret;
|
|
|
|
clk_dis_all:
|
|
clk_disable_unprepare(xqspi->refclk);
|
|
clk_dis_pclk:
|
|
clk_disable_unprepare(xqspi->pclk);
|
|
remove_master:
|
|
spi_controller_put(ctlr);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* zynq_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 on success and error value on failure
|
|
*/
|
|
static void zynq_qspi_remove(struct platform_device *pdev)
|
|
{
|
|
struct zynq_qspi *xqspi = platform_get_drvdata(pdev);
|
|
|
|
zynq_qspi_write(xqspi, ZYNQ_QSPI_ENABLE_OFFSET, 0);
|
|
|
|
clk_disable_unprepare(xqspi->refclk);
|
|
clk_disable_unprepare(xqspi->pclk);
|
|
}
|
|
|
|
static const struct of_device_id zynq_qspi_of_match[] = {
|
|
{ .compatible = "xlnx,zynq-qspi-1.0", },
|
|
{ /* end of table */ }
|
|
};
|
|
|
|
MODULE_DEVICE_TABLE(of, zynq_qspi_of_match);
|
|
|
|
/*
|
|
* zynq_qspi_driver - This structure defines the QSPI platform driver
|
|
*/
|
|
static struct platform_driver zynq_qspi_driver = {
|
|
.probe = zynq_qspi_probe,
|
|
.remove_new = zynq_qspi_remove,
|
|
.driver = {
|
|
.name = "zynq-qspi",
|
|
.of_match_table = zynq_qspi_of_match,
|
|
},
|
|
};
|
|
|
|
module_platform_driver(zynq_qspi_driver);
|
|
|
|
MODULE_AUTHOR("Xilinx, Inc.");
|
|
MODULE_DESCRIPTION("Xilinx Zynq QSPI driver");
|
|
MODULE_LICENSE("GPL");
|