Hi, On 08/21/2015 02:20 AM, Marek Vasut wrote: > From: Graham Moore <grmoore@xxxxxxxxxxxxxxxxxxxxx> > > Add support for the Cadence QSPI controller. This controller is > present in the Altera SoCFPGA SoCs and this driver has been tested > on the Cyclone V SoC. can we add info about the modes supported/not supported like direct mode, indirect etc. > > Signed-off-by: Graham Moore <grmoore@xxxxxxxxxxxxxxxxxxxxx> > Signed-off-by: Marek Vasut <marex@xxxxxxx> > Cc: Alan Tull <atull@xxxxxxxxxxxxxxxxxxxxx> > Cc: Brian Norris <computersforpeace@xxxxxxxxx> > Cc: David Woodhouse <dwmw2@xxxxxxxxxxxxx> > Cc: Dinh Nguyen <dinguyen@xxxxxxxxxxxxxxxxxxxxx> > Cc: Graham Moore <grmoore@xxxxxxxxxxxxxxxxxxxxx> > Cc: Vikas MANOCHA <vikas.manocha@xxxxxx> > Cc: Yves Vandervennet <yvanderv@xxxxxxxxxxxxxxxxxxxxx> > Cc: devicetree@xxxxxxxxxxxxxxx > --- > drivers/mtd/spi-nor/Kconfig | 11 + > drivers/mtd/spi-nor/Makefile | 1 + > drivers/mtd/spi-nor/cadence-quadspi.c | 1260 +++++++++++++++++++++++++++++++++ > 3 files changed, 1272 insertions(+) > create mode 100644 drivers/mtd/spi-nor/cadence-quadspi.c > > V2: use NULL instead of modalias in spi_nor_scan call > V3: Use existing property is-decoded-cs instead of creating duplicate. > V4: Support Micron quad mode by snooping command stream for EVCR command > and subsequently configuring Cadence controller for quad mode. > V5: Clean up sparse and smatch complaints. Remove snooping of Micron > quad mode. Add comment on XIP mode bit and dummy clock cycles. Set > up SRAM partition at 1:1 during init. > V6: Remove dts patch that was included by mistake. Incorporate Vikas's > comments regarding fifo width, SRAM partition setting, and trigger > address. Trigger address was added as an unsigned int, as it is not > an IO resource per se, and does not need to be mapped. Also add > Marek Vasut's workaround for picking up OF properties on subnodes. > V7: - Perform coding-style cleanup and type fixes. Remove ugly QSPI_*() > macros and replace them with functions. Get rid of unused variables. > - Implement support for nor->set_protocol() to handle Quad-command, > this patch now depends on the following patch: > mtd: spi-nor: notify (Q)SPI controller about protocol change > - Replace that cqspi_fifo_read() disaster with plain old readsl() > and cqspi_fifo_write() tentacle horror with pretty writesl(). > - Remove CQSPI_SUPPORT_XIP_CHIPS, which is broken. > - Get rid of cqspi_find_chipselect() mess, instead just place the > struct cqspi_st and chipselect number into struct cqspi_flash_pdata > and set nor->priv to the struct cqspi_flash_pdata of that particular > chip. > - Replace the odd math in calculate_ticks_for_ns() with DIV_ROUND_UP(). > - Make variables const where applicable. > V8: - Implement a function to wait for bit being set/unset for a given > period of time and use it to replace the ad-hoc bits of code. > - Configure the write underflow watermark to be 1/8 if FIFO size. > - Extract out the SPI NOR flash probing code into separate function > to clearly mark what will soon be considered a boilerplate code. > - Repair the handling of mode bits, which caused instability in V7. > - Clean up the interrupt handling > - Fix Kconfig help text and make the patch depend on OF and COMPILE_TEST. > > diff --git a/drivers/mtd/spi-nor/Kconfig b/drivers/mtd/spi-nor/Kconfig > index 89bf4c1..ed253a2 100644 > --- a/drivers/mtd/spi-nor/Kconfig > +++ b/drivers/mtd/spi-nor/Kconfig > @@ -40,4 +40,15 @@ config SPI_NXP_SPIFI > Flash. Enable this option if you have a device with a SPIFI > controller and want to access the Flash as a mtd device. > > +config SPI_CADENCE_QUADSPI > + tristate "Cadence Quad SPI controller" > + depends on OF && COMPILE_TEST > + help > + Enable support for the Cadence Quad SPI Flash controller. > + > + Cadence QSPI is a specialized controller for connecting an SPI > + Flash over 1/2/4-bit wide bus. Enable this option if you have a > + device with a Cadence QSPI controller and want to access the > + Flash as an MTD device. > + > endif # MTD_SPI_NOR > diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile > index e53333e..446c6b9 100644 > --- a/drivers/mtd/spi-nor/Makefile > +++ b/drivers/mtd/spi-nor/Makefile > @@ -1,3 +1,4 @@ > obj-$(CONFIG_MTD_SPI_NOR) += spi-nor.o > +obj-$(CONFIG_SPI_CADENCE_QUADSPI) += cadence-quadspi.o > obj-$(CONFIG_SPI_FSL_QUADSPI) += fsl-quadspi.o > obj-$(CONFIG_SPI_NXP_SPIFI) += nxp-spifi.o > diff --git a/drivers/mtd/spi-nor/cadence-quadspi.c b/drivers/mtd/spi-nor/cadence-quadspi.c > new file mode 100644 > index 0000000..8e024b8 > --- /dev/null > +++ b/drivers/mtd/spi-nor/cadence-quadspi.c > @@ -0,0 +1,1260 @@ > +/* > + * Driver for Cadence QSPI Controller > + * > + * Copyright Altera Corporation (C) 2012-2014. All rights reserved. > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms and conditions of the GNU General Public License, > + * version 2, as published by the Free Software Foundation. > + * > + * This program is distributed in the hope it will be useful, but WITHOUT > + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for > + * more details. > + * > + * You should have received a copy of the GNU General Public License along with > + * this program. If not, see <http://www.gnu.org/licenses/>. > + */ > +#include <linux/clk.h> > +#include <linux/completion.h> > +#include <linux/delay.h> > +#include <linux/err.h> > +#include <linux/errno.h> > +#include <linux/interrupt.h> > +#include <linux/io.h> > +#include <linux/jiffies.h> > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/mtd/mtd.h> > +#include <linux/mtd/partitions.h> > +#include <linux/mtd/spi-nor.h> > +#include <linux/of_device.h> > +#include <linux/of.h> > +#include <linux/platform_device.h> > +#include <linux/sched.h> > +#include <linux/spi/spi.h> > +#include <linux/timer.h> > + > +#define CQSPI_NAME "cadence-qspi" > +#define CQSPI_MAX_CHIPSELECT 16 > + > +struct cqspi_st; > + > +struct cqspi_flash_pdata { > + struct mtd_info mtd; > + struct spi_nor nor; > + struct cqspi_st *cqspi; > + u32 clk_rate; > + u32 read_delay; > + u32 tshsl_ns; > + u32 tsd2d_ns; > + u32 tchsh_ns; > + u32 tslch_ns; > + u8 inst_width; > + u8 addr_width; > + u8 cs; > +}; > + > +struct cqspi_st { > + struct platform_device *pdev; > + > + struct clk *clk; > + unsigned int sclk; > + > + void __iomem *iobase; > + void __iomem *ahb_base; > + struct completion transfer_complete; > + > + int current_cs; > + unsigned long master_ref_clk_hz; > + bool is_decoded_cs; > + u32 fifo_depth; > + u32 fifo_width; > + u32 trigger_address; > + struct cqspi_flash_pdata f_pdata[CQSPI_MAX_CHIPSELECT]; > +}; [...] > +#define CQSPI_REG_CMDADDRESS 0x94 > +#define CQSPI_REG_CMDREADDATALOWER 0xA0 > +#define CQSPI_REG_CMDREADDATAUPPER 0xA4 > +#define CQSPI_REG_CMDWRITEDATALOWER 0xA8 > +#define CQSPI_REG_CMDWRITEDATAUPPER 0xAC > + > +/* Interrupt status bits */ > +#define CQSPI_REG_IRQ_MODE_ERR BIT(0) > +#define CQSPI_REG_IRQ_UNDERFLOW BIT(1) > +#define CQSPI_REG_IRQ_IND_COMP BIT(2) > +#define CQSPI_REG_IRQ_IND_RD_REJECT BIT(3) > +#define CQSPI_REG_IRQ_WR_PROTECTED_ERR BIT(4) > +#define CQSPI_REG_IRQ_ILLEGAL_AHB_ERR BIT(5) remove unused MACROs. > +#define CQSPI_REG_IRQ_WATERMARK BIT(6) > +#define CQSPI_REG_IRQ_IND_RD_OVERFLOW BIT(12) Correct this bit name to ..IND_RD_SRAM_FULL. > + > +#define CQSPI_IRQ_MASK_RD (CQSPI_REG_IRQ_WATERMARK | \ > + CQSPI_REG_IRQ_IND_RD_OVERFLOW | \ > + CQSPI_REG_IRQ_IND_COMP) > + > +#define CQSPI_IRQ_MASK_WR (CQSPI_REG_IRQ_IND_COMP | \ > + CQSPI_REG_IRQ_WATERMARK | \ > + CQSPI_REG_IRQ_UNDERFLOW) > + > +#define CQSPI_IRQ_STATUS_MASK 0x1FFFF > + > +static int cqspi_wait_for_bit(void __iomem *reg, const u32 mask, bool clear) > +{ > + unsigned long end = jiffies + msecs_to_jiffies(CQSPI_TIMEOUT_MS); > + u32 val; > + > + while (1) { > + val = readl(reg); > + if (clear) > + val = ~val; > + val &= mask; > + > + if (val == mask) > + return 0; > + > + if (time_after(jiffies, end)) > + return -ETIMEDOUT; > + } > +} > + > +static bool cqspi_is_idle(struct cqspi_st *cqspi) > +{ > + u32 reg = readl(cqspi->iobase + CQSPI_REG_CONFIG); > + > + return reg & (1 << CQSPI_REG_CONFIG_IDLE_LSB); > +} > + > +static u32 cqspi_get_rd_sram_level(struct cqspi_st *cqspi) > +{ > + u32 reg = readl(cqspi->iobase + CQSPI_REG_SDRAMLEVEL); > + > + reg >>= CQSPI_REG_SDRAMLEVEL_RD_LSB; > + return reg & CQSPI_REG_SDRAMLEVEL_RD_MASK; > +} > + > +static irqreturn_t cqspi_irq_handler(int this_irq, void *dev) > +{ > + struct cqspi_st *cqspi = dev; > + unsigned int irq_status; > + > + /* Read interrupt status */ no need of this comment. > + irq_status = readl(cqspi->iobase + CQSPI_REG_IRQSTATUS); > + > + /* Clear interrupt */ > + writel(irq_status, cqspi->iobase + CQSPI_REG_IRQSTATUS); > + > + irq_status &= CQSPI_IRQ_MASK_RD | CQSPI_IRQ_MASK_WR; > + > + if (irq_status) > + complete(&cqspi->transfer_complete); > + > + return IRQ_HANDLED; > +} > + > +static unsigned int cqspi_calc_rdreg(struct spi_nor *nor, const u8 opcode) > +{ > + unsigned int rdreg = 0; > + struct cqspi_flash_pdata *f_pdata = nor->priv; > + > + rdreg |= f_pdata->inst_width << CQSPI_REG_RD_INSTR_TYPE_INSTR_LSB; > + rdreg |= f_pdata->addr_width << CQSPI_REG_RD_INSTR_TYPE_ADDR_LSB; > + > + if (nor->flash_read == SPI_NOR_QUAD) > + rdreg |= CQSPI_INST_TYPE_QUAD > + << CQSPI_REG_RD_INSTR_TYPE_DATA_LSB; > + return rdreg; > +} > + > +static int cqspi_wait_idle(struct cqspi_st *cqspi) > +{ > + const unsigned int poll_idle_retry = 3; > + unsigned int count = 0; > + unsigned long timeout; > + > + timeout = jiffies + msecs_to_jiffies(CQSPI_TIMEOUT_MS); > + while (1) { > + /* > + * Read few times in succession to ensure the controller > + * is indeed idle, that is, the bit does not transition > + * low again. > + */ > + if (cqspi_is_idle(cqspi)) > + count++; > + else > + count = 0; > + > + if (count >= poll_idle_retry) > + return 0; why do we need to check it 3 times ? > > + > + if (time_after(jiffies, timeout)) { > + /* Timeout, in busy mode. */ > + dev_err(&cqspi->pdev->dev, > + "QSPI is still busy after %dms timeout.\n", > + CQSPI_TIMEOUT_MS); > + return -ETIMEDOUT; > + } > + > + cpu_relax(); > + } > +} > + [...] > + > +static int cqspi_indirect_read_execute(struct spi_nor *nor, > + u8 *rxbuf, const unsigned n_rx) > +{ > + struct cqspi_flash_pdata *f_pdata = nor->priv; > + struct cqspi_st *cqspi = f_pdata->cqspi; > + void __iomem *reg_base = cqspi->iobase; > + void __iomem *ahb_base = cqspi->ahb_base; > + unsigned int remaining = n_rx; > + unsigned int bytes_to_read = 0; > + int ret = 0; > + > + writel(remaining, reg_base + CQSPI_REG_INDIRECTRDBYTES); > + > + /* Clear all interrupts. */ > + writel(CQSPI_IRQ_STATUS_MASK, reg_base + CQSPI_REG_IRQSTATUS); > + > + writel(CQSPI_IRQ_MASK_RD, reg_base + CQSPI_REG_IRQMASK); I think there is no need for separate masks for read & write. Use one mask & configure it once in the init rather than configuring each time for every read/write. Then in the ISR, take action as per the interrupt source: read/write/error condition etc. > + > + reinit_completion(&cqspi->transfer_complete); > + writel(CQSPI_REG_INDIRECTRD_START_MASK, > + reg_base + CQSPI_REG_INDIRECTRD); > + > + while (remaining > 0) { > + ret = wait_for_completion_timeout(&cqspi->transfer_complete, > + msecs_to_jiffies > + (CQSPI_READ_TIMEOUT_MS)); > + > + bytes_to_read = cqspi_get_rd_sram_level(cqspi); > + > + if (!ret && bytes_to_read == 0) { > + dev_err(nor->dev, "Indirect read timeout, no bytes\n"); > + ret = -ETIMEDOUT; > + goto failrd; > + } > + > + while (bytes_to_read != 0) { > + bytes_to_read *= cqspi->fifo_width; > + bytes_to_read = bytes_to_read > remaining ? > + remaining : bytes_to_read; > + readsl(ahb_base, rxbuf, DIV_ROUND_UP(bytes_to_read, 4)); > + rxbuf += bytes_to_read; > + remaining -= bytes_to_read; > + bytes_to_read = cqspi_get_rd_sram_level(cqspi); > + } > + } > + > + /* Check indirect done status */ > + ret = cqspi_wait_for_bit(reg_base + CQSPI_REG_INDIRECTRD, > + CQSPI_REG_INDIRECTRD_DONE_MASK, 0); > + if (ret) { > + dev_err(nor->dev, > + "Indirect read completion error (%i)\n", ret); > + goto failrd; > + } > + > + /* Disable interrupt */ > + writel(0, reg_base + CQSPI_REG_IRQMASK); > + > + /* Clear indirect completion status */ > + writel(CQSPI_REG_INDIRECTRD_DONE_MASK, reg_base + CQSPI_REG_INDIRECTRD); > + > + return 0; > + > +failrd: > + /* Disable interrupt */ > + writel(0, reg_base + CQSPI_REG_IRQMASK); > + > + /* Cancel the indirect read */ > + writel(CQSPI_REG_INDIRECTWR_CANCEL_MASK, > + reg_base + CQSPI_REG_INDIRECTRD); > + return ret; > +} > + > +static int cqspi_indirect_write_setup(struct spi_nor *nor, > + const unsigned int to_addr) > +{ > + unsigned int reg; > + struct cqspi_flash_pdata *f_pdata = nor->priv; > + struct cqspi_st *cqspi = f_pdata->cqspi; > + void __iomem *reg_base = cqspi->iobase; > + > + /* Set opcode. */ > + reg = nor->program_opcode << CQSPI_REG_WR_INSTR_OPCODE_LSB; > + writel(reg, reg_base + CQSPI_REG_WR_INSTR); > + reg = cqspi_calc_rdreg(nor, nor->program_opcode); > + writel(reg, reg_base + CQSPI_REG_RD_INSTR); > + > + writel(to_addr, reg_base + CQSPI_REG_INDIRECTWRSTARTADDR); > + > + reg = readl(reg_base + CQSPI_REG_SIZE); > + reg &= ~CQSPI_REG_SIZE_ADDRESS_MASK; > + reg |= (nor->addr_width - 1); > + writel(reg, reg_base + CQSPI_REG_SIZE); > + return 0; > +} > + > +static int cqspi_indirect_write_execute(struct spi_nor *nor, > + const u8 *txbuf, const unsigned n_tx) > +{ > + const unsigned int page_size = nor->page_size; > + struct cqspi_flash_pdata *f_pdata = nor->priv; > + struct cqspi_st *cqspi = f_pdata->cqspi; > + void __iomem *reg_base = cqspi->iobase; > + unsigned int remaining = n_tx; > + unsigned int write_bytes; > + int ret; > + > + writel(remaining, reg_base + CQSPI_REG_INDIRECTWRBYTES); > + > + /* Clear all interrupts. */ > + writel(CQSPI_IRQ_STATUS_MASK, reg_base + CQSPI_REG_IRQSTATUS); > + > + writel(CQSPI_IRQ_MASK_WR, reg_base + CQSPI_REG_IRQMASK); as above, no need for separate masks for read & write. Use one mask & configure it once in the init rather than configuring each time for every read/write. > + > + reinit_completion(&cqspi->transfer_complete); > + writel(CQSPI_REG_INDIRECTWR_START_MASK, > + reg_base + CQSPI_REG_INDIRECTWR); > + > + while (remaining > 0) { > + write_bytes = remaining > page_size ? page_size : remaining; > + writesl(cqspi->ahb_base, txbuf, DIV_ROUND_UP(write_bytes, 4)); > + > + ret = wait_for_completion_timeout(&cqspi->transfer_complete, > + msecs_to_jiffies > + (CQSPI_TIMEOUT_MS)); > + if (!ret) { > + dev_err(nor->dev, "Indirect write timeout\n"); > + ret = -ETIMEDOUT; > + goto failwr; > + } > + > + txbuf += write_bytes; > + remaining -= write_bytes; > + } > + > + /* Check indirect done status */ > + ret = cqspi_wait_for_bit(reg_base + CQSPI_REG_INDIRECTWR, > + CQSPI_REG_INDIRECTWR_DONE_MASK, 0); > + if (ret) { > + dev_err(nor->dev, > + "Indirect write completion error (%i)\n", ret); > + goto failwr; > + } > + > + /* Disable interrupt. */ > + writel(0, reg_base + CQSPI_REG_IRQMASK); > + > + /* Clear indirect completion status */ > + writel(CQSPI_REG_INDIRECTWR_DONE_MASK, reg_base + CQSPI_REG_INDIRECTWR); > + > + cqspi_wait_idle(cqspi); > + > + return 0; > + > +failwr: > + /* Disable interrupt. */ > + writel(0, reg_base + CQSPI_REG_IRQMASK); > + > + /* Cancel the indirect write */ > + writel(CQSPI_REG_INDIRECTWR_CANCEL_MASK, > + reg_base + CQSPI_REG_INDIRECTWR); > + return ret; > +} > + [...] > + > +static void cqspi_controller_enable(struct cqspi_st *cqspi) > +{ > + void __iomem *reg_base = cqspi->iobase; > + unsigned int reg; > + > + reg = readl(reg_base + CQSPI_REG_CONFIG); > + reg |= CQSPI_REG_CONFIG_ENABLE_MASK; > + writel(reg, reg_base + CQSPI_REG_CONFIG); > +} > + > +static void cqspi_controller_disable(struct cqspi_st *cqspi) > +{ > + void __iomem *reg_base = cqspi->iobase; > + unsigned int reg; > + > + reg = readl(reg_base + CQSPI_REG_CONFIG); > + reg &= ~CQSPI_REG_CONFIG_ENABLE_MASK; > + writel(reg, reg_base + CQSPI_REG_CONFIG); > +} two above function are almost same, we can have one function by adding one bool arg. > + > +static void cqspi_switch_cs(struct spi_nor *nor) > +{ > + struct cqspi_flash_pdata *f_pdata = nor->priv; > + struct cqspi_st *cqspi = f_pdata->cqspi; > + void __iomem *iobase = cqspi->iobase; > + unsigned int reg; > + > + cqspi_controller_disable(cqspi); > + > + /* configure page size and block size. */ > + reg = readl(iobase + CQSPI_REG_SIZE); > + reg &= ~(CQSPI_REG_SIZE_PAGE_MASK << CQSPI_REG_SIZE_PAGE_LSB); > + reg &= ~(CQSPI_REG_SIZE_BLOCK_MASK << CQSPI_REG_SIZE_BLOCK_LSB); > + reg &= ~CQSPI_REG_SIZE_ADDRESS_MASK; > + reg |= (nor->page_size << CQSPI_REG_SIZE_PAGE_LSB); > + reg |= (ilog2(nor->mtd->erasesize) << CQSPI_REG_SIZE_BLOCK_LSB); > + reg |= (nor->addr_width - 1); > + writel(reg, iobase + CQSPI_REG_SIZE); > + > + /* configure the chip select */ > + cqspi_chipselect(nor); > + > + cqspi_controller_enable(cqspi); > +} > + > +static int cqspi_prep(struct spi_nor *nor, enum spi_nor_ops ops) > +{ > + struct cqspi_flash_pdata *f_pdata = nor->priv; > + struct cqspi_st *cqspi = f_pdata->cqspi; > + const unsigned int sclk = f_pdata->clk_rate; > + > + /* Switch chip select. */ > + if (cqspi->current_cs != f_pdata->cs) { > + cqspi->current_cs = f_pdata->cs; > + cqspi_switch_cs(nor); > + } > + > + /* Setup baudrate divisor and delays */ > + if (cqspi->sclk != sclk) { > + cqspi->sclk = sclk; > + cqspi_controller_disable(cqspi); > + cqspi_config_baudrate_div(cqspi, sclk); > + cqspi_delay(nor, sclk); > + cqspi_readdata_capture(cqspi, 1, f_pdata->read_delay); > + cqspi_controller_enable(cqspi); > + } > + return 0; > +} > + > +static int cqspi_read_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len) > +{ > + int ret; > + > + cqspi_prep(nor, SPI_NOR_OPS_READ); > + > + ret = cqspi_command_read(nor, &opcode, 1, buf, len); > + return ret; > +} > + > +static int cqspi_write_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len, > + int write_enable) > +{ > + int ret = 0; > + > + cqspi_prep(nor, SPI_NOR_OPS_WRITE); > + > + ret = cqspi_command_write(nor, opcode, buf, len); > + return ret; > +} > + > +static int cqspi_of_get_flash_pdata(struct platform_device *pdev, > + struct cqspi_flash_pdata *f_pdata, > + struct device_node *np) > +{ > + if (of_property_read_u32(np, "cdns,read-delay", &f_pdata->read_delay)) { > + dev_err(&pdev->dev, "couldn't determine read-delay\n"); > + return -ENXIO; > + } > + > + if (of_property_read_u32(np, "cdns,tshsl-ns", &f_pdata->tshsl_ns)) { > + dev_err(&pdev->dev, "couldn't determine tshsl-ns\n"); > + return -ENXIO; > + } > + > + if (of_property_read_u32(np, "cdns,tsd2d-ns", &f_pdata->tsd2d_ns)) { > + dev_err(&pdev->dev, "couldn't determine tsd2d-ns\n"); > + return -ENXIO; > + } > + > + if (of_property_read_u32(np, "cdns,tchsh-ns", &f_pdata->tchsh_ns)) { > + dev_err(&pdev->dev, "couldn't determine tchsh-ns\n"); > + return -ENXIO; > + } > + > + if (of_property_read_u32(np, "cdns,tslch-ns", &f_pdata->tslch_ns)) { > + dev_err(&pdev->dev, "couldn't determine tslch-ns\n"); > + return -ENXIO; > + } > + > + if (of_property_read_u32(np, "spi-max-frequency", &f_pdata->clk_rate)) { > + dev_err(&pdev->dev, "couldn't determine spi-max-frequency\n"); > + return -ENXIO; > + } > + > + return 0; > +} > + > +static int cqspi_of_get_pdata(struct platform_device *pdev) > +{ > + struct device_node *np = pdev->dev.of_node; > + struct cqspi_st *cqspi = platform_get_drvdata(pdev); > + > + cqspi->is_decoded_cs = of_property_read_bool(np, "cdns,is-decoded-cs"); > + > + if (of_property_read_u32(np, "cdns,fifo-depth", &cqspi->fifo_depth)) { > + dev_err(&pdev->dev, "couldn't determine fifo-depth\n"); > + return -ENXIO; > + } > + > + if (of_property_read_u32(np, "cdns,fifo-width", &cqspi->fifo_width)) { > + dev_err(&pdev->dev, "couldn't determine fifo-width\n"); > + return -ENXIO; > + } > + > + if (of_property_read_u32(np, "cdns,trigger-address", > + &cqspi->trigger_address)) { > + dev_err(&pdev->dev, "couldn't determine trigger-address\n"); > + return -ENXIO; > + } > + > + return 0; > +} > + > +static void cqspi_controller_init(struct cqspi_st *cqspi) > +{ > + cqspi_controller_disable(cqspi); > + > + /* Configure the remap address register, no remap */ > + writel(0, cqspi->iobase + CQSPI_REG_REMAP); > + > + /* Disable all interrupts. */ > + writel(0, cqspi->iobase + CQSPI_REG_IRQMASK); > + > + /* Configure the SRAM split to 1:1 . */ The comment is rightly using "SRAM" but the variable name "fifo_depth" is misleading, change it to sram_depth. > + writel(cqspi->fifo_depth / 2, cqspi->iobase + CQSPI_REG_SRAMPARTITION); > + > + /* Load indirect trigger address. */ remove this comment & review other comments of this function. I would remove at least first two comments also of the routine. > + writel(cqspi->trigger_address, > + cqspi->iobase + CQSPI_REG_INDIRECTTRIGGER); > + > + /* Program read watermark -- 1/2 of the FIFO. */ > + writel(cqspi->fifo_depth * cqspi->fifo_width / 2, > + cqspi->iobase + CQSPI_REG_INDIRECTRDWATERMARK); > + /* Program write watermark -- 1/8 of the FIFO. */ > + writel(cqspi->fifo_depth * cqspi->fifo_width / 8, > + cqspi->iobase + CQSPI_REG_INDIRECTWRWATERMARK); > + > + cqspi_controller_enable(cqspi); > +} > + > +static int cqspi_setup_flash(struct cqspi_st *cqspi, struct device_node *np) > +{ > + struct platform_device *pdev = cqspi->pdev; > + struct device *dev = &pdev->dev; > + struct mtd_part_parser_data ppdata; > + struct cqspi_flash_pdata *f_pdata; > + struct spi_nor *nor; > + struct mtd_info *mtd; > + unsigned int cs; > + int i, ret; > + > + /* Get flash device data */ > + for_each_available_child_of_node(dev->of_node, np) { > + if (of_property_read_u32(np, "reg", &cs)) { > + dev_err(dev, "Couldn't determine chip select.\n"); > + goto err; > + } > + > + if (cs > CQSPI_MAX_CHIPSELECT) { > + dev_err(dev, "Chip select %d out of range.\n", cs); > + goto err; > + } > + > + f_pdata = &cqspi->f_pdata[cs]; > + f_pdata->cqspi = cqspi; > + f_pdata->cs = cs; > + > + ret = cqspi_of_get_flash_pdata(pdev, f_pdata, np); > + if (ret) > + goto err; > + > + nor = &f_pdata->nor; > + mtd = &f_pdata->mtd; > + > + mtd->priv = nor; > + > + nor->mtd = mtd; > + nor->dev = dev; > + nor->dn = np; > + nor->priv = f_pdata; > + > + nor->read_reg = cqspi_read_reg; > + nor->write_reg = cqspi_write_reg; > + nor->read = cqspi_read; > + nor->write = cqspi_write; > + nor->erase = cqspi_erase; > + nor->prepare = cqspi_prep; > + nor->set_protocol = cqspi_set_protocol; > + > + ret = spi_nor_scan(nor, NULL, SPI_NOR_QUAD); > + if (ret) > + goto err; > + > + ppdata.of_node = np; > + ret = mtd_device_parse_register(mtd, NULL, &ppdata, NULL, 0); > + if (ret) > + goto err; > + } > + > + return 0; > + > +err: > + for (i = 0; i < CQSPI_MAX_CHIPSELECT; i++) > + if (cqspi->f_pdata[i].mtd.name) > + mtd_device_unregister(&cqspi->f_pdata[i].mtd); > + return ret; > +} > + > +static int cqspi_probe(struct platform_device *pdev) > +{ > + struct device_node *np = pdev->dev.of_node; > + struct device *dev = &pdev->dev; > + struct cqspi_st *cqspi; > + struct resource *res; > + struct resource *res_ahb; > + int ret; > + int irq; > + > + cqspi = devm_kzalloc(dev, sizeof(*cqspi), GFP_KERNEL); > + if (!cqspi) > + return -ENOMEM; > + > + cqspi->pdev = pdev; > + platform_set_drvdata(pdev, cqspi); > + > + /* Obtain configuration from OF. */ > + ret = cqspi_of_get_pdata(pdev); > + if (ret) { > + dev_err(dev, "Cannot get mandatory OF data.\n"); > + return -ENODEV; > + } > + > + /* Obtain QSPI clock. */ > + cqspi->clk = devm_clk_get(dev, NULL); > + if (IS_ERR(cqspi->clk)) { > + dev_err(dev, "Cannot claim QSPI clock.\n"); > + return PTR_ERR(cqspi->clk); > + } > + > + cqspi->master_ref_clk_hz = clk_get_rate(cqspi->clk); > + > + /* Obtain and remap controller address. */ > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + cqspi->iobase = devm_ioremap_resource(dev, res); > + if (IS_ERR(cqspi->iobase)) { > + dev_err(dev, "Cannot remap controller address.\n"); > + return PTR_ERR(cqspi->iobase); > + } > + > + /* Obtain and remap AHB address. */ > + res_ahb = platform_get_resource(pdev, IORESOURCE_MEM, 1); > + cqspi->ahb_base = devm_ioremap_resource(dev, res_ahb); > + if (IS_ERR(cqspi->ahb_base)) { > + dev_err(dev, "Cannot remap AHB address.\n"); > + return PTR_ERR(cqspi->ahb_base); > + } > + > + init_completion(&cqspi->transfer_complete); > + > + /* Obtain IRQ line. */ > + irq = platform_get_irq(pdev, 0); > + if (irq < 0) { > + dev_err(dev, "Cannot obtain IRQ.\n"); > + return -ENXIO; > + } > + > + ret = devm_request_irq(dev, irq, cqspi_irq_handler, 0, > + pdev->name, cqspi); > + if (ret) { > + dev_err(dev, "Cannot request IRQ.\n"); > + return ret; > + } > + > + cqspi_wait_idle(cqspi); why do we need it here ? Cheers, Vikas > + cqspi_controller_init(cqspi); > + cqspi->current_cs = -1; > + cqspi->sclk = 0; > + > + ret = cqspi_setup_flash(cqspi, np); > + if (ret) { > + dev_err(dev, "Cadence QSPI NOR probe failed %d\n", ret); > + cqspi_controller_disable(cqspi); > + } > + > + return ret; > +} > + > +static int cqspi_remove(struct platform_device *pdev) > +{ > + struct cqspi_st *cqspi = platform_get_drvdata(pdev); > + int i; > + > + cqspi_controller_disable(cqspi); > + > + for (i = 0; i < CQSPI_MAX_CHIPSELECT; i++) > + if (cqspi->f_pdata[i].mtd.name) > + mtd_device_unregister(&cqspi->f_pdata[i].mtd); > + > + return 0; > +} > + > +#ifdef CONFIG_PM_SLEEP > +static int cqspi_suspend(struct device *dev) > +{ > + struct cqspi_st *cqspi = dev_get_drvdata(dev); > + > + cqspi_controller_disable(cqspi); > + return 0; > +} > + > +static int cqspi_resume(struct device *dev) > +{ > + struct cqspi_st *cqspi = dev_get_drvdata(dev); > + > + cqspi_controller_enable(cqspi); > + return 0; > +} > + > +static const struct dev_pm_ops cqspi__dev_pm_ops = { > + .suspend = cqspi_suspend, > + .resume = cqspi_resume, > +}; > + > +#define CQSPI_DEV_PM_OPS (&cqspi__dev_pm_ops) > +#else > +#define CQSPI_DEV_PM_OPS NULL > +#endif > + > +static struct of_device_id const cqspi_dt_ids[] = { > + {.compatible = "cdns,qspi-nor",}, > + { /* end of table */ } > +}; > + > +MODULE_DEVICE_TABLE(of, cqspi_dt_ids); > + > +static struct platform_driver cqspi_platform_driver = { > + .probe = cqspi_probe, > + .remove = cqspi_remove, > + .driver = { > + .name = CQSPI_NAME, > + .pm = CQSPI_DEV_PM_OPS, > + .of_match_table = cqspi_dt_ids, > + }, > +}; > + > +module_platform_driver(cqspi_platform_driver); > + > +MODULE_DESCRIPTION("Cadence QSPI Controller Driver"); > +MODULE_LICENSE("GPL v2"); > +MODULE_ALIAS("platform:" CQSPI_NAME); > +MODULE_AUTHOR("Ley Foon Tan <lftan@xxxxxxxxxx>"); > +MODULE_AUTHOR("Graham Moore <grmoore@xxxxxxxxxxxxxxxxxxxxx>"); > -- > 2.1.4 > > . > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
