Re: [PATCH v8 2/3] mtd: spi-nor: add rockchip serial flash controller driver

[Heiko Stuebner <heiko@sntech.de>]

Hi Andy,

Am Sonntag, 8. April 2018, 14:08:45 CEST schrieb Andy Yan:
> ping

We're in the middle of the merge-window right now, so I do guess
maintainers will possibly do other things than looking at new code.

But you might want to address the kbuild-robot issue and resend
in the meantime, as sometimes maintainers also tend to ignore patches
with open kbuild-robot issues.


Heiko

> 
> 2018-02-08 20:18 GMT+08:00 Andy Yan <andy.yan@rock-chips.com>:
> 
> > From: Shawn Lin <shawn.lin@rock-chips.com>
> >
> > Add Rockchip SFC(serial flash controller) driver.
> >
> > Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
> > Signed-off-by: Andy Yan <andy.yan@rock-chips.com>
> > Acked-by: Marek Vasut <marek.vasut@gmail.com>
> >
> > ---
> >
> > Changes in v8:
> > - remove unused macro SFC_CMD_TRAN_BYTES_MASK
> > - set max transfer length to 15.5KB
> > - remove unnecessary buffer align check
> > - remove the duplicate logic what spi-nor.c already does for spi_nor_write
> > - add spi_nor_erase, as the SFC should get the erase address.
> >
> > Changes in v7:
> > - correct the fifo status check in pio read/write mode.
> > - copy data from user buffer to dma buffer
> >
> > Changes in v6:
> > - fold in Andy's improvement for checking fifo level
> >   before pio read
> > - rename the controller to rv1108 since offically it's
> >   renamed and acked by Rob.
> > - use dma_coerce_mask_and_coherent suggested by Andy.
> >
> > Changes in v5:
> > - check if the buf is aligned to 32bit
> > - check if the buf for dma comes from vmalloc
> > - fix to use 1-1-n according to the current framework
> > - avoid bytes cnt overflow
> >
> > Changes in v4:
> > - use uppercase DMA for description
> > - simplify the code of get_if_type
> > - use dma_dir to simplify the code
> > - simplify the rockchip_sfc_do_rd_wr
> > - some minor improvements
> > - add reset controller when doing resume
> >
> > Changes in v3:
> > - use io{read32,write32}_rep to simplify the corner cases
> > - remove more unnecessary bit definitions
> > - some minor comment fixes and improvement
> > - fix wrong unregister function
> > - unify more code
> > - use nor to avoid constantly replicating the whole
> >   sfc->flash[sfc->num_chip].nor
> > - add email for MODULE_AUTHOR
> > - remove #if 1 --- #endif
> > - extract DMA code to imporve the code structure
> > - reset all when failing to do dma
> > - pass sfc to get_if_type
> > - rename sfc-no-dma to sfc-no-DMA
> >
> > Changes in v2:
> > - fix typos
> > - add some comment for buffer and others operations
> > - rename SFC_MAX_CHIP_NUM to MAX_CHIPSELECT_NUM
> > - use u8 for cs
> > - return -EINVAL for default case of get_if_type
> > - use readl_poll_*() to check timeout cases
> > - simplify and clarify some condition checks
> > - rework the bitshifts to simplify the code
> > - define SFC_CMD_DUMMY(x)
> > - fix ummap for dma read path and finish all the
> >   cache maintenance.
> > - rename to rockchip_sfc_chip_priv and embed struct spi_nor
> >   in it.
> > - add MODULE_AUTHOR
> > - add runtime PM and general PM support.
> > - Thanks for Marek's comments. Link:
> >   http://lists.infradead.org/pipermail/linux-mtd/2016-November/070321.html
> >
> >  MAINTAINERS                        |   9 +
> >  drivers/mtd/spi-nor/Kconfig        |   7 +
> >  drivers/mtd/spi-nor/Makefile       |   1 +
> >  drivers/mtd/spi-nor/rockchip-sfc.c | 942 ++++++++++++++++++++++++++++++
> > +++++++
> >  4 files changed, 959 insertions(+)
> >  create mode 100644 drivers/mtd/spi-nor/rockchip-sfc.c
> >
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index aa71ab52f..0718bc0 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -11704,6 +11704,15 @@ F:     drivers/gpio/gpio-bd9571mwv.c
> >  F:     include/linux/mfd/bd9571mwv.h
> >  F:     Documentation/devicetree/bindings/mfd/bd9571mwv.txt
> >
> > +ROCKCHIP SERIAL FLASH CONTROLLER DRIVER
> > +M:     Shawn Lin <shawn.lin@rock-chips.com>
> > +M:     Andy Yan <andy.yan@rock-chips.com>
> > +L:     linux-mtd@lists.infradead.org
> > +L:     linux-rockchip@lists.infradead.org
> > +S:     Maintained
> > +F:     Documentation/devicetree/bindings/mtd/rockchip-sfc.txt
> > +F:     drivers/mtd/spi-nor/rockchip-sfc.c
> > +
> >  ROSE NETWORK LAYER
> >  M:     Ralf Baechle <ralf@linux-mips.org>
> >  L:     linux-hams@vger.kernel.org
> > diff --git a/drivers/mtd/spi-nor/Kconfig b/drivers/mtd/spi-nor/Kconfig
> > index 89da88e..f2898ea 100644
> > --- a/drivers/mtd/spi-nor/Kconfig
> > +++ b/drivers/mtd/spi-nor/Kconfig
> > @@ -129,4 +129,11 @@ config SPI_STM32_QUADSPI
> >           This enables support for the STM32 Quad SPI controller.
> >           We only connect the NOR to this controller.
> >
> > +config SPI_ROCKCHIP_SFC
> > +       tristate "Rockchip Serial Flash Controller(SFC)"
> > +       depends on ARCH_ROCKCHIP || COMPILE_TEST
> > +       depends on HAS_IOMEM && HAS_DMA
> > +       help
> > +         This enables support for rockchip serial flash controller.
> > +
> >  endif # MTD_SPI_NOR
> > diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile
> > index f4c61d2..c294156 100644
> > --- a/drivers/mtd/spi-nor/Makefile
> > +++ b/drivers/mtd/spi-nor/Makefile
> > @@ -11,3 +11,4 @@ obj-$(CONFIG_SPI_INTEL_SPI)   += intel-spi.o
> >  obj-$(CONFIG_SPI_INTEL_SPI_PCI)        += intel-spi-pci.o
> >  obj-$(CONFIG_SPI_INTEL_SPI_PLATFORM)   += intel-spi-platform.o
> >  obj-$(CONFIG_SPI_STM32_QUADSPI)        += stm32-quadspi.o
> > +obj-$(CONFIG_SPI_ROCKCHIP_SFC) += rockchip-sfc.o
> > diff --git a/drivers/mtd/spi-nor/rockchip-sfc.c b/drivers/mtd/spi-nor/
> > rockchip-sfc.c
> > new file mode 100644
> > index 0000000..6037101
> > --- /dev/null
> > +++ b/drivers/mtd/spi-nor/rockchip-sfc.c
> > @@ -0,0 +1,942 @@
> > +/*
> > + * Rockchip Serial Flash Controller Driver
> > + *
> > + * Copyright (c) 2017, Rockchip Inc.
> > + * Author: Shawn Lin <shawn.lin@rock-chips.com>
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License as published by
> > + * the Free Software Foundation; either version 2 of the License, or
> > + * (at your option) any later version.
> > + *
> > + * This program is distributed in the hope that 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/bitops.h>
> > +#include <linux/clk.h>
> > +#include <linux/completion.h>
> > +#include <linux/dma-mapping.h>
> > +#include <linux/iopoll.h>
> > +#include <linux/mm.h>
> > +#include <linux/module.h>
> > +#include <linux/mtd/mtd.h>
> > +#include <linux/mtd/spi-nor.h>
> > +#include <linux/of.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/pm_runtime.h>
> > +#include <linux/slab.h>
> > +
> > +/* System control */
> > +#define SFC_CTRL                       0x0
> > +#define  SFC_CTRL_COMMON_BITS_1                0x0
> > +#define  SFC_CTRL_COMMON_BITS_2                0x1
> > +#define  SFC_CTRL_COMMON_BITS_4                0x2
> > +#define  SFC_CTRL_DATA_BITS_SHIFT      12
> > +#define  SFC_CTRL_ADDR_BITS_SHIFT      10
> > +#define  SFC_CTRL_CMD_BITS_SHIFT       8
> > +#define  SFC_CTRL_PHASE_SEL_NEGETIVE   BIT(1)
> > +
> > +/* Interrupt mask */
> > +#define SFC_IMR                                0x4
> > +#define  SFC_IMR_RX_FULL               BIT(0)
> > +#define  SFC_IMR_RX_UFLOW              BIT(1)
> > +#define  SFC_IMR_TX_OFLOW              BIT(2)
> > +#define  SFC_IMR_TX_EMPTY              BIT(3)
> > +#define  SFC_IMR_TRAN_FINISH           BIT(4)
> > +#define  SFC_IMR_BUS_ERR               BIT(5)
> > +#define  SFC_IMR_NSPI_ERR              BIT(6)
> > +#define  SFC_IMR_DMA                   BIT(7)
> > +
> > +/* Interrupt clear */
> > +#define SFC_ICLR                       0x8
> > +#define  SFC_ICLR_RX_FULL              BIT(0)
> > +#define  SFC_ICLR_RX_UFLOW             BIT(1)
> > +#define  SFC_ICLR_TX_OFLOW             BIT(2)
> > +#define  SFC_ICLR_TX_EMPTY             BIT(3)
> > +#define  SFC_ICLR_TRAN_FINISH          BIT(4)
> > +#define  SFC_ICLR_BUS_ERR              BIT(5)
> > +#define  SFC_ICLR_NSPI_ERR             BIT(6)
> > +#define  SFC_ICLR_DMA                  BIT(7)
> > +
> > +/* FIFO threshold level */
> > +#define SFC_FTLR                       0xc
> > +#define  SFC_FTLR_TX_SHIFT             0
> > +#define  SFC_FTLR_TX_MASK              0x1f
> > +#define  SFC_FTLR_RX_SHIFT             8
> > +#define  SFC_FTLR_RX_MASK              0x1f
> > +
> > +/* Reset FSM and FIFO */
> > +#define SFC_RCVR                       0x10
> > +#define  SFC_RCVR_RESET                        BIT(0)
> > +
> > +/* Enhanced mode */
> > +#define SFC_AX                         0x14
> > +
> > +/* Address Bit number */
> > +#define SFC_ABIT                       0x18
> > +
> > +/* Interrupt status */
> > +#define SFC_ISR                                0x1c
> > +#define  SFC_ISR_RX_FULL_SHIFT         BIT(0)
> > +#define  SFC_ISR_RX_UFLOW_SHIFT                BIT(1)
> > +#define  SFC_ISR_TX_OFLOW_SHIFT                BIT(2)
> > +#define  SFC_ISR_TX_EMPTY_SHIFT                BIT(3)
> > +#define  SFC_ISR_TX_FINISH_SHIFT       BIT(4)
> > +#define  SFC_ISR_BUS_ERR_SHIFT         BIT(5)
> > +#define  SFC_ISR_NSPI_ERR_SHIFT                BIT(6)
> > +#define  SFC_ISR_DMA_SHIFT             BIT(7)
> > +
> > +/* FIFO status */
> > +#define SFC_FSR                                0x20
> > +#define  SFC_FSR_TX_IS_FULL            BIT(0)
> > +#define  SFC_FSR_TX_IS_EMPTY           BIT(1)
> > +#define  SFC_FSR_RX_IS_EMPTY           BIT(2)
> > +#define  SFC_FSR_RX_IS_FULL            BIT(3)
> > +#define  SFC_FSR_TXLV_MASK             GENMASK(12, 8)
> > +#define  SFC_FSR_TXLV_SHIFT            8
> > +#define  SFC_FSR_RXLV_MASK             GENMASK(20, 16)
> > +#define  SFC_FSR_RXLV_SHIFT            16
> > +
> > +/* FSM status */
> > +#define SFC_SR                         0x24
> > +#define  SFC_SR_IS_IDLE                        0x0
> > +#define  SFC_SR_IS_BUSY                        0x1
> > +
> > +/* Raw interrupt status */
> > +#define SFC_RISR                       0x28
> > +#define  SFC_RISR_RX_FULL              BIT(0)
> > +#define  SFC_RISR_RX_UNDERFLOW         BIT(1)
> > +#define  SFC_RISR_TX_OVERFLOW          BIT(2)
> > +#define  SFC_RISR_TX_EMPTY             BIT(3)
> > +#define  SFC_RISR_TRAN_FINISH          BIT(4)
> > +#define  SFC_RISR_BUS_ERR              BIT(5)
> > +#define  SFC_RISR_NSPI_ERR             BIT(6)
> > +#define  SFC_RISR_DMA                  BIT(7)
> > +
> > +/* Master trigger */
> > +#define SFC_DMA_TRIGGER                        0x80
> > +
> > +/* Src or Dst addr for master */
> > +#define SFC_DMA_ADDR                   0x84
> > +
> > +/* Command */
> > +#define SFC_CMD                                0x100
> > +#define  SFC_CMD_IDX_SHIFT             0
> > +#define  SFC_CMD_DUMMY_SHIFT           8
> > +#define  SFC_CMD_DIR_RD                        0
> > +#define  SFC_CMD_DIR_WR                        1
> > +#define  SFC_CMD_DIR_SHIFT             12
> > +#define  SFC_CMD_ADDR_ZERO             (0x0 << 14)
> > +#define  SFC_CMD_ADDR_24BITS           (0x1 << 14)
> > +#define  SFC_CMD_ADDR_32BITS           (0x2 << 14)
> > +#define  SFC_CMD_ADDR_FRS              (0x3 << 14)
> > +#define  SFC_CMD_TRAN_BYTES_SHIFT      16
> > +#define  SFC_CMD_CS_SHIFT              30
> > +
> > +/* Address */
> > +#define SFC_ADDR                       0x104
> > +
> > +/* Data */
> > +#define SFC_DATA                       0x108
> > +
> > +#define SFC_MAX_CHIPSELECT_NUM         4
> > +
> > +/* The SFC can transfer max 16KB - 1 at one time
> > + * we set it to 15.5KB here for alignment.
> > + */
> > +#define SFC_MAX_TRANS_BYTES            (512 * 31)
> > +
> > +#define SFC_CMD_DUMMY(x) \
> > +       ((x) << SFC_CMD_DUMMY_SHIFT)
> > +
> > +enum rockchip_sfc_iftype {
> > +       IF_TYPE_STD,
> > +       IF_TYPE_DUAL,
> > +       IF_TYPE_QUAD,
> > +};
> > +
> > +struct rockchip_sfc;
> > +struct rockchip_sfc_chip_priv {
> > +       u8 cs;
> > +       u32 clk_rate;
> > +       struct spi_nor nor;
> > +       struct rockchip_sfc *sfc;
> > +};
> > +
> > +struct rockchip_sfc {
> > +       struct device *dev;
> > +       struct mutex lock;
> > +       void __iomem *regbase;
> > +       struct clk *hclk;
> > +       struct clk *clk;
> > +       /* virtual mapped addr for dma_buffer */
> > +       void *buffer;
> > +       dma_addr_t dma_buffer;
> > +       struct completion cp;
> > +       struct rockchip_sfc_chip_priv flash[SFC_MAX_CHIPSELECT_NUM];
> > +       u32 num_chip;
> > +       bool use_dma;
> > +};
> > +
> > +static int get_if_type(struct rockchip_sfc *sfc, enum spi_nor_protocol
> > proto)
> > +{
> > +       if (proto == SNOR_PROTO_1_1_2)
> > +               return IF_TYPE_DUAL;
> > +       else if (proto == SNOR_PROTO_1_1_4)
> > +               return IF_TYPE_QUAD;
> > +       else if (proto == SNOR_PROTO_1_1_1)
> > +               return IF_TYPE_STD;
> > +
> > +       dev_err(sfc->dev, "unsupported SPI read mode\n");
> > +
> > +       return -EINVAL;
> > +}
> > +
> > +static int rockchip_sfc_reset(struct rockchip_sfc *sfc)
> > +{
> > +       int err;
> > +       u32 status;
> > +
> > +       writel_relaxed(SFC_RCVR_RESET, sfc->regbase + SFC_RCVR);
> > +
> > +       err = readl_poll_timeout(sfc->regbase + SFC_RCVR, status,
> > +                                !(status & SFC_RCVR_RESET), 20,
> > +                                jiffies_to_usecs(HZ));
> > +       if (err)
> > +               dev_err(sfc->dev, "SFC reset never finished\n");
> > +
> > +       /* Still need to clear the masked interrupt from RISR */
> > +       writel_relaxed(SFC_ICLR_RX_FULL | SFC_ICLR_RX_UFLOW |
> > +                      SFC_ICLR_TX_OFLOW | SFC_ICLR_TX_EMPTY |
> > +                      SFC_ICLR_TRAN_FINISH | SFC_ICLR_BUS_ERR |
> > +                      SFC_ICLR_NSPI_ERR | SFC_ICLR_DMA,
> > +                      sfc->regbase + SFC_ICLR);
> > +
> > +       dev_info(sfc->dev, "reset\n");
> > +
> > +       return err;
> > +}
> > +
> > +static int rockchip_sfc_init(struct rockchip_sfc *sfc)
> > +{
> > +       int err;
> > +
> > +       err = rockchip_sfc_reset(sfc);
> > +       if (err)
> > +               return err;
> > +
> > +       /* Mask all eight interrupts */
> > +       writel_relaxed(0xff, sfc->regbase + SFC_IMR);
> > +
> > +       writel_relaxed(SFC_CTRL_PHASE_SEL_NEGETIVE, sfc->regbase +
> > SFC_CTRL);
> > +
> > +       return 0;
> > +}
> > +
> > +static int rockchip_sfc_prep(struct spi_nor *nor, enum spi_nor_ops ops)
> > +{
> > +       struct rockchip_sfc_chip_priv *priv = nor->priv;
> > +       struct rockchip_sfc *sfc = priv->sfc;
> > +       int ret;
> > +
> > +       mutex_lock(&sfc->lock);
> > +       pm_runtime_get_sync(sfc->dev);
> > +
> > +       ret = clk_set_rate(sfc->clk, priv->clk_rate);
> > +       if (ret)
> > +               goto out;
> > +
> > +       ret = clk_prepare_enable(sfc->clk);
> > +       if (ret)
> > +               goto out;
> > +
> > +       return 0;
> > +
> > +out:
> > +       mutex_unlock(&sfc->lock);
> > +       return ret;
> > +}
> > +
> > +static void rockchip_sfc_unprep(struct spi_nor *nor, enum spi_nor_ops ops)
> > +{
> > +       struct rockchip_sfc_chip_priv *priv = nor->priv;
> > +       struct rockchip_sfc *sfc = priv->sfc;
> > +
> > +       clk_disable_unprepare(sfc->clk);
> > +       mutex_unlock(&sfc->lock);
> > +       pm_runtime_mark_last_busy(sfc->dev);
> > +       pm_runtime_put_autosuspend(sfc->dev);
> > +}
> > +
> > +static inline int rockchip_sfc_get_fifo_level(struct rockchip_sfc *sfc,
> > int wr)
> > +{
> > +       u32 fsr = readl_relaxed(sfc->regbase + SFC_FSR);
> > +       int level;
> > +
> > +       if (wr)
> > +               level = (fsr & SFC_FSR_TXLV_MASK) >> SFC_FSR_TXLV_SHIFT;
> > +       else
> > +               level = (fsr & SFC_FSR_RXLV_MASK) >> SFC_FSR_RXLV_SHIFT;
> > +
> > +       return level;
> > +}
> > +
> > +static int rockchip_sfc_wait_fifo_ready(struct rockchip_sfc *sfc, int
> > wr, u32 timeout)
> > +{
> > +       unsigned long deadline = jiffies + timeout;
> > +       int level;
> > +
> > +       while (!(level = rockchip_sfc_get_fifo_level(sfc, wr))) {
> > +               if (time_after_eq(jiffies, deadline)) {
> > +                       dev_warn(sfc->dev, "%s fifo timeout\n", wr ?
> > "write" : "read");
> > +                       return -ETIMEDOUT;
> > +               }
> > +               udelay(1);
> > +       }
> > +
> > +       return level;
> > +}
> > +
> > +/* The SFC_CTRL register is a global control register,
> > + * when the controller is in busy state(SFC_SR),
> > + * SFC_CTRL cannot be set.
> > + */
> > +static void rockchip_sfc_wait_idle(struct rockchip_sfc *sfc, u32
> > timeout_us)
> > +{
> > +       u32 status;
> > +       int ret;
> > +
> > +       ret = readl_poll_timeout(sfc->regbase + SFC_SR, status,
> > +                               !(status & SFC_SR_IS_BUSY),
> > +                               20, timeout_us);
> > +       if (ret) {
> > +               dev_err(sfc->dev, "wait sfc idle timeout\n");
> > +               rockchip_sfc_reset(sfc);
> > +       }
> > +}
> > +
> > +static void rockchip_sfc_setup_ctrl(struct rockchip_sfc *sfc)
> > +{
> > +       u32 reg;
> > +
> > +       reg = IF_TYPE_STD << SFC_CTRL_DATA_BITS_SHIFT;
> > +       reg |= IF_TYPE_STD << SFC_CTRL_ADDR_BITS_SHIFT;
> > +       reg |= IF_TYPE_STD << SFC_CTRL_CMD_BITS_SHIFT;
> > +       reg |= SFC_CTRL_PHASE_SEL_NEGETIVE;
> > +
> > +       rockchip_sfc_wait_idle(sfc, 10000);
> > +
> > +       writel_relaxed(reg, sfc->regbase + SFC_CTRL);
> > +}
> > +static int rockchip_sfc_op_reg(struct spi_nor *nor,
> > +                              u8 opcode, int len, u8 optype)
> > +{
> > +       struct rockchip_sfc_chip_priv *priv = nor->priv;
> > +       struct rockchip_sfc *sfc = priv->sfc;
> > +       u32 reg;
> > +
> > +       rockchip_sfc_setup_ctrl(sfc);
> > +
> > +       reg = opcode << SFC_CMD_IDX_SHIFT;
> > +       reg |= len << SFC_CMD_TRAN_BYTES_SHIFT;
> > +       reg |= priv->cs << SFC_CMD_CS_SHIFT;
> > +       reg |= optype << SFC_CMD_DIR_SHIFT;
> > +       writel_relaxed(reg, sfc->regbase + SFC_CMD);
> > +
> > +       return 0;
> > +}
> > +
> > +static int rockchip_sfc_write_fifo(struct rockchip_sfc *sfc, u8 *buf, int
> > len)
> > +{
> > +       u8 bytes = len & 0x3;
> > +       u32 dwords;
> > +       int tx_level;
> > +       u32 write_words;
> > +       u32 tmp = 0;
> > +
> > +       if (len >= 4) {
> > +               dwords = len >> 2;
> > +               while (dwords) {
> > +                       tx_level = rockchip_sfc_wait_fifo_ready(sfc,
> > SFC_CMD_DIR_WR, HZ);
> > +                       if (tx_level < 0)
> > +                               return tx_level;
> > +                       write_words = min_t(u32, tx_level, dwords);
> > +                       iowrite32_rep(sfc->regbase + SFC_DATA, buf,
> > write_words);
> > +                       buf += write_words << 2;
> > +                       dwords -= write_words;
> > +               }
> > +       }
> > +
> > +       /* write the rest non word aligned bytes */
> > +       if (bytes) {
> > +               tx_level = rockchip_sfc_wait_fifo_ready(sfc,
> > SFC_CMD_DIR_WR, HZ);
> > +               if (tx_level < 0)
> > +                       return tx_level;
> > +               memcpy(&tmp, buf, bytes);
> > +               writel_relaxed(tmp, sfc->regbase + SFC_DATA);
> > +       }
> > +
> > +       return len;
> > +}
> > +
> > +static int rockchip_sfc_read_fifo(struct rockchip_sfc *sfc, u8 *buf, int
> > len)
> > +{
> > +       u8 bytes = len & 0x3;
> > +       u32 dwords;
> > +       u8 read_words;
> > +       int rx_level;
> > +       int tmp;
> > +
> > +       /* word aligned access only */
> > +       if (len >= 4) {
> > +               dwords = len >> 2;
> > +               while (dwords) {
> > +                       rx_level = rockchip_sfc_wait_fifo_ready(sfc,
> > SFC_CMD_DIR_RD, HZ);
> > +                       if (rx_level < 0)
> > +                               return rx_level;
> > +                       read_words = min_t(u32, rx_level, dwords);
> > +                       ioread32_rep(sfc->regbase + SFC_DATA, buf,
> > read_words);
> > +                       buf += read_words << 2;
> > +                       dwords -= read_words;
> > +               }
> > +       }
> > +
> > +       /* read the rest non word aligned bytes */
> > +       if (bytes) {
> > +               rx_level = rockchip_sfc_wait_fifo_ready(sfc,
> > SFC_CMD_DIR_RD, HZ);
> > +               if (rx_level < 0)
> > +                       return rx_level;
> > +               tmp = readl_relaxed(sfc->regbase + SFC_DATA);
> > +               memcpy(buf, &tmp, bytes);
> > +       }
> > +
> > +       return len;
> > +}
> > +
> > +static int rockchip_sfc_read_reg(struct spi_nor *nor, u8 opcode,
> > +                                u8 *buf, int len)
> > +{
> > +       struct rockchip_sfc_chip_priv *priv = nor->priv;
> > +       struct rockchip_sfc *sfc = priv->sfc;
> > +       int ret;
> > +       int trans;
> > +
> > +       trans = min_t(int, len, SFC_MAX_TRANS_BYTES);
> > +       ret = rockchip_sfc_op_reg(nor, opcode, trans, SFC_CMD_DIR_RD);
> > +       if (ret)
> > +               return ret;
> > +
> > +       ret = rockchip_sfc_read_fifo(sfc, buf, trans);
> > +       if (ret < 0)
> > +               return ret;
> > +
> > +       return 0;
> > +}
> > +
> > +static int rockchip_sfc_write_reg(struct spi_nor *nor, u8 opcode,
> > +                                 u8 *buf, int len)
> > +{
> > +       struct rockchip_sfc_chip_priv *priv = nor->priv;
> > +       struct rockchip_sfc *sfc = priv->sfc;
> > +       int ret;
> > +
> > +       ret = rockchip_sfc_op_reg(nor, opcode, len, SFC_CMD_DIR_WR);
> > +       if (ret)
> > +               return ret;
> > +       ret = rockchip_sfc_write_fifo(sfc, buf, len);
> > +       if (ret < 0)
> > +               return ret;
> > +
> > +       return 0;
> > +}
> > +
> > +static int rockchip_sfc_erase(struct spi_nor *nor, loff_t offs)
> > +{
> > +       struct rockchip_sfc_chip_priv *priv = nor->priv;
> > +       struct rockchip_sfc *sfc = priv->sfc;
> > +       u32 reg;
> > +
> > +       rockchip_sfc_setup_ctrl(sfc);
> > +
> > +       reg = nor->erase_opcode << SFC_CMD_IDX_SHIFT;
> > +       reg |= (nor->addr_width == 4) ?
> > +               SFC_CMD_ADDR_32BITS : SFC_CMD_ADDR_24BITS;
> > +       reg |= priv->cs << SFC_CMD_CS_SHIFT;
> > +       reg |= SFC_CMD_DIR_WR << SFC_CMD_DIR_SHIFT;
> > +
> > +       writel_relaxed(reg, sfc->regbase + SFC_CMD);
> > +
> > +       writel_relaxed(offs, sfc->regbase + SFC_ADDR);
> > +
> > +       return 0;
> > +}
> > +
> > +static int rockchip_sfc_setup_transfer(struct spi_nor *nor,
> > +                                              loff_t from_to,
> > +                                              size_t len, u8 op_type)
> > +{
> > +       struct rockchip_sfc_chip_priv *priv = nor->priv;
> > +       struct rockchip_sfc *sfc = priv->sfc;
> > +       u8 if_type = IF_TYPE_STD;
> > +       u32 reg;
> > +
> > +       if (op_type == SFC_CMD_DIR_RD)
> > +               if_type = get_if_type(sfc, nor->read_proto);
> > +
> > +       rockchip_sfc_wait_idle(sfc, 10000);
> > +
> > +       writel_relaxed((if_type << SFC_CTRL_DATA_BITS_SHIFT) |
> > +                      (IF_TYPE_STD << SFC_CTRL_ADDR_BITS_SHIFT) |
> > +                      (IF_TYPE_STD << SFC_CTRL_CMD_BITS_SHIFT) |
> > +                      SFC_CTRL_PHASE_SEL_NEGETIVE,
> > +                      sfc->regbase + SFC_CTRL);
> > +
> > +       if (op_type == SFC_CMD_DIR_WR)
> > +               reg = nor->program_opcode << SFC_CMD_IDX_SHIFT;
> > +       else
> > +               reg = nor->read_opcode << SFC_CMD_IDX_SHIFT;
> > +
> > +       reg |= op_type << SFC_CMD_DIR_SHIFT;
> > +       reg |= (nor->addr_width == 4) ?
> > +               SFC_CMD_ADDR_32BITS : SFC_CMD_ADDR_24BITS;
> > +
> > +       reg |= priv->cs << SFC_CMD_CS_SHIFT;
> > +       reg |= len << SFC_CMD_TRAN_BYTES_SHIFT;
> > +
> > +       if (op_type == SFC_CMD_DIR_RD)
> > +               reg |= SFC_CMD_DUMMY(nor->read_dummy);
> > +
> > +       writel_relaxed(reg, sfc->regbase + SFC_CMD);
> > +       writel_relaxed(from_to, sfc->regbase + SFC_ADDR);
> > +
> > +       return 0;
> > +}
> > +
> > +static int rockchip_sfc_do_dma_transfer(struct spi_nor *nor, loff_t
> > from_to,
> > +                                       dma_addr_t dma_buf, size_t len,
> > +                                       u8 op_type)
> > +{
> > +       struct rockchip_sfc_chip_priv *priv = nor->priv;
> > +       struct rockchip_sfc *sfc = priv->sfc;
> > +       u32 reg;
> > +       int err = 0;
> > +
> > +       init_completion(&sfc->cp);
> > +
> > +       writel_relaxed(SFC_ICLR_RX_FULL | SFC_ICLR_RX_UFLOW |
> > +                      SFC_ICLR_TX_OFLOW | SFC_ICLR_TX_EMPTY |
> > +                      SFC_ICLR_TRAN_FINISH | SFC_ICLR_BUS_ERR |
> > +                      SFC_ICLR_NSPI_ERR | SFC_ICLR_DMA,
> > +                      sfc->regbase + SFC_ICLR);
> > +
> > +       /* Enable transfer complete interrupt */
> > +       reg = readl_relaxed(sfc->regbase + SFC_IMR);
> > +       reg &= ~SFC_IMR_TRAN_FINISH;
> > +       writel_relaxed(reg, sfc->regbase + SFC_IMR);
> > +
> > +       err = rockchip_sfc_setup_transfer(nor, from_to, len, op_type);
> > +       if (err < 0)
> > +               return err;
> > +
> > +       writel_relaxed(dma_buf, sfc->regbase + SFC_DMA_ADDR);
> > +
> > +       /*
> > +        * Start dma but note that the sfc->dma_buffer is derived from
> > +        * dmam_alloc_coherent so we don't actually need any sync
> > operations
> > +        * for coherent dma memory.
> > +        */
> > +       writel_relaxed(0x1, sfc->regbase + SFC_DMA_TRIGGER);
> > +
> > +       /* Wait for the interrupt. */
> > +       if (!wait_for_completion_timeout(&sfc->cp,
> > msecs_to_jiffies(2000))) {
> > +               dev_err(sfc->dev, "DMA wait for transfer finish
> > timeout\n");
> > +               err = -ETIMEDOUT;
> > +       }
> > +
> > +       writel_relaxed(SFC_ICLR_RX_FULL | SFC_ICLR_RX_UFLOW |
> > +                      SFC_ICLR_TX_OFLOW | SFC_ICLR_TX_EMPTY |
> > +                      SFC_ICLR_TRAN_FINISH | SFC_ICLR_BUS_ERR |
> > +                      SFC_ICLR_NSPI_ERR | SFC_ICLR_DMA,
> > +                      sfc->regbase + SFC_ICLR);
> > +       /* Disable transfer finish interrupt */
> > +       reg = readl_relaxed(sfc->regbase + SFC_IMR);
> > +       reg |= SFC_IMR_TRAN_FINISH;
> > +       writel_relaxed(reg, sfc->regbase + SFC_IMR);
> > +
> > +       if (err) {
> > +               rockchip_sfc_reset(sfc);
> > +               return err;
> > +       }
> > +
> > +       return 0;
> > +}
> > +
> > +static inline int rockchip_sfc_pio_write(struct rockchip_sfc *sfc, u_char
> > *buf,
> > +                                        size_t len)
> > +{
> > +       return rockchip_sfc_write_fifo(sfc, buf, len);
> > +}
> > +
> > +static inline int rockchip_sfc_pio_read(struct rockchip_sfc *sfc, u_char
> > *buf,
> > +                                       size_t len)
> > +{
> > +       return rockchip_sfc_read_fifo(sfc, buf, len);
> > +}
> > +
> > +static int rockchip_sfc_pio_transfer(struct spi_nor *nor, loff_t from_to,
> > +                                    size_t len, u_char *buf, u8 op_type)
> > +{
> > +       struct rockchip_sfc_chip_priv *priv = nor->priv;
> > +       struct rockchip_sfc *sfc = priv->sfc;
> > +       size_t trans;
> > +       int ret;
> > +
> > +       trans = min_t(size_t, SFC_MAX_TRANS_BYTES, len);
> > +       ret = rockchip_sfc_setup_transfer(nor, from_to, trans, op_type);
> > +       if (ret < 0)
> > +               return ret;
> > +
> > +       if (op_type == SFC_CMD_DIR_WR)
> > +               ret = rockchip_sfc_pio_write(sfc, buf, trans);
> > +       else
> > +               ret = rockchip_sfc_pio_read(sfc, buf, trans);
> > +
> > +       return ret;
> > +}
> > +
> > +static int rockchip_sfc_dma_transfer(struct spi_nor *nor, loff_t from_to,
> > +                                    size_t len, u_char *buf, u8 op_type)
> > +{
> > +       struct rockchip_sfc_chip_priv *priv = nor->priv;
> > +       struct rockchip_sfc *sfc = priv->sfc;
> > +       size_t trans;
> > +       int ret;
> > +
> > +       trans = min_t(size_t, SFC_MAX_TRANS_BYTES, len);
> > +
> > +       if (op_type == SFC_CMD_DIR_WR)
> > +               memcpy(sfc->buffer, buf, trans);
> > +
> > +       ret = rockchip_sfc_do_dma_transfer(nor, from_to, sfc->dma_buffer,
> > +                                          trans, op_type);
> > +       if (ret) {
> > +               dev_warn(nor->dev, "DMA timeout\n");
> > +               return ret;
> > +       }
> > +
> > +       if (op_type == SFC_CMD_DIR_RD)
> > +               memcpy(buf, sfc->buffer, trans);
> > +
> > +       return trans;
> > +}
> > +
> > +static ssize_t rockchip_sfc_do_rd_wr(struct spi_nor *nor, loff_t from_to,
> > +                                    size_t len, u_char *buf, u32 op_type)
> > +{
> > +       struct rockchip_sfc_chip_priv *priv = nor->priv;
> > +       struct rockchip_sfc *sfc = priv->sfc;
> > +
> > +       /* DMA can only handle word anligned transfer chunks */
> > +       if (likely(sfc->use_dma) && !(len & 0x3))
> > +               return rockchip_sfc_dma_transfer(nor, from_to, len, buf,
> > op_type);
> > +       else
> > +               return rockchip_sfc_pio_transfer(nor, from_to, len,
> > +                                                (u_char *)buf, op_type);
> > +}
> > +
> > +static ssize_t rockchip_sfc_read(struct spi_nor *nor, loff_t from,
> > +                                size_t len, u_char *read_buf)
> > +{
> > +       return rockchip_sfc_do_rd_wr(nor, from, len,
> > +                                    read_buf, SFC_CMD_DIR_RD);
> > +}
> > +
> > +static ssize_t rockchip_sfc_write(struct spi_nor *nor, loff_t to,
> > +                                 size_t len, const u_char *write_buf)
> > +{
> > +       return rockchip_sfc_do_rd_wr(nor, to, len,
> > +                                    (u_char *)write_buf,
> > +                                    SFC_CMD_DIR_WR);
> > +}
> > +
> > +static int rockchip_sfc_register(struct device_node *np,
> > +                                struct rockchip_sfc *sfc)
> > +{
> > +       const struct spi_nor_hwcaps hwcaps = {
> > +               .mask = SNOR_HWCAPS_READ |
> > +                       SNOR_HWCAPS_READ_FAST |
> > +                       SNOR_HWCAPS_READ_1_1_2 |
> > +                       SNOR_HWCAPS_READ_1_1_4 |
> > +                       SNOR_HWCAPS_PP,
> > +       };
> > +       struct device *dev = sfc->dev;
> > +       struct mtd_info *mtd;
> > +       struct spi_nor *nor;
> > +       int ret;
> > +
> > +       nor = &sfc->flash[sfc->num_chip].nor;
> > +       nor->dev = dev;
> > +       spi_nor_set_flash_node(nor, np);
> > +
> > +       ret = of_property_read_u8(np, "reg", &sfc->flash[sfc->num_chip].cs)
> > ;
> > +       if (ret) {
> > +               dev_err(dev, "No reg property for %s\n",
> > +                       np->full_name);
> > +               return ret;
> > +       }
> > +
> > +       ret = of_property_read_u32(np, "spi-max-frequency",
> > +                                  &sfc->flash[sfc->num_chip].clk_rate);
> > +       if (ret) {
> > +               dev_err(dev, "No spi-max-frequency property for %s\n",
> > +                       np->full_name);
> > +               return ret;
> > +       }
> > +
> > +       sfc->flash[sfc->num_chip].sfc = sfc;
> > +       nor->priv = &sfc->flash[sfc->num_chip];
> > +
> > +       nor->prepare = rockchip_sfc_prep;
> > +       nor->unprepare = rockchip_sfc_unprep;
> > +       nor->read_reg = rockchip_sfc_read_reg;
> > +       nor->write_reg = rockchip_sfc_write_reg;
> > +       nor->read = rockchip_sfc_read;
> > +       nor->write = rockchip_sfc_write;
> > +       nor->erase = rockchip_sfc_erase;
> > +       ret = spi_nor_scan(nor, NULL, &hwcaps);
> > +       if (ret)
> > +               return ret;
> > +
> > +       mtd = &nor->mtd;
> > +       mtd->name = np->name;
> > +       ret = mtd_device_register(mtd, NULL, 0);
> > +       if (ret)
> > +               return ret;
> > +
> > +       sfc->num_chip++;
> > +       return 0;
> > +}
> > +
> > +static void rockchip_sfc_unregister_all(struct rockchip_sfc *sfc)
> > +{
> > +       int i;
> > +
> > +       for (i = 0; i < sfc->num_chip; i++)
> > +               mtd_device_unregister(&sfc->flash[i].nor.mtd);
> > +}
> > +
> > +static int rockchip_sfc_register_all(struct rockchip_sfc *sfc)
> > +{
> > +       struct device *dev = sfc->dev;
> > +       struct device_node *np;
> > +       int ret;
> > +
> > +       for_each_available_child_of_node(dev->of_node, np) {
> > +               ret = rockchip_sfc_register(np, sfc);
> > +               if (ret)
> > +                       goto fail;
> > +
> > +               if (sfc->num_chip == SFC_MAX_CHIPSELECT_NUM) {
> > +                       dev_warn(dev, "Exceeds the max cs limitation\n");
> > +                       break;
> > +               }
> > +       }
> > +
> > +       return 0;
> > +
> > +fail:
> > +       dev_err(dev, "Failed to register all chips\n");
> > +       /* Unregister all the _registered_ nor flash */
> > +       rockchip_sfc_unregister_all(sfc);
> > +       return ret;
> > +}
> > +
> > +static irqreturn_t rockchip_sfc_irq_handler(int irq, void *dev_id)
> > +{
> > +       struct rockchip_sfc *sfc = dev_id;
> > +       u32 reg;
> > +
> > +       reg = readl_relaxed(sfc->regbase + SFC_RISR);
> > +
> > +       /* Clear interrupt */
> > +       writel_relaxed(reg, sfc->regbase + SFC_ICLR);
> > +
> > +       if (reg & SFC_RISR_TRAN_FINISH)
> > +               complete(&sfc->cp);
> > +
> > +       return IRQ_HANDLED;
> > +}
> > +
> > +static int rockchip_sfc_probe(struct platform_device *pdev)
> > +{
> > +       struct device *dev = &pdev->dev;
> > +       struct resource *res;
> > +       struct rockchip_sfc *sfc;
> > +       int ret;
> > +
> > +       sfc = devm_kzalloc(dev, sizeof(*sfc), GFP_KERNEL);
> > +       if (!sfc)
> > +               return -ENOMEM;
> > +
> > +       platform_set_drvdata(pdev, sfc);
> > +       sfc->dev = dev;
> > +
> > +       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > +       sfc->regbase = devm_ioremap_resource(dev, res);
> > +       if (IS_ERR(sfc->regbase))
> > +               return PTR_ERR(sfc->regbase);
> > +
> > +       sfc->clk = devm_clk_get(&pdev->dev, "sfc");
> > +       if (IS_ERR(sfc->clk)) {
> > +               dev_err(&pdev->dev, "Failed to get sfc interface clk\n");
> > +               return PTR_ERR(sfc->clk);
> > +       }
> > +
> > +       sfc->hclk = devm_clk_get(&pdev->dev, "hsfc");
> > +       if (IS_ERR(sfc->hclk)) {
> > +               dev_err(&pdev->dev, "Failed to get sfc ahp clk\n");
> > +               return PTR_ERR(sfc->hclk);
> > +       }
> > +
> > +       ret = dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(32));
> > +       if (ret) {
> > +               dev_warn(dev, "Unable to set dma mask\n");
> > +               return ret;
> > +       }
> > +
> > +       sfc->buffer = dmam_alloc_coherent(dev, SFC_MAX_TRANS_BYTES,
> > +                                         &sfc->dma_buffer,
> > +                                         GFP_KERNEL);
> > +       if (!sfc->buffer)
> > +               return -ENOMEM;
> > +
> > +       mutex_init(&sfc->lock);
> > +
> > +       ret = clk_prepare_enable(sfc->hclk);
> > +       if (ret) {
> > +               dev_err(&pdev->dev, "Failed to enable hclk\n");
> > +               goto err_hclk;
> > +       }
> > +
> > +       ret = clk_prepare_enable(sfc->clk);
> > +       if (ret) {
> > +               dev_err(&pdev->dev, "Failed to enable clk\n");
> > +               goto err_clk;
> > +       }
> > +
> > +       sfc->use_dma = !of_property_read_bool(sfc->dev->of_node,
> > +                                             "rockchip,sfc-no-dma");
> > +
> > +       /* Find the irq */
> > +       ret = platform_get_irq(pdev, 0);
> > +       if (ret < 0) {
> > +               dev_err(dev, "Failed to get the irq\n");
> > +               goto err_irq;
> > +       }
> > +
> > +       ret = devm_request_irq(dev, ret, rockchip_sfc_irq_handler,
> > +                              0, pdev->name, sfc);
> > +       if (ret) {
> > +               dev_err(dev, "Failed to request irq\n");
> > +               goto err_irq;
> > +       }
> > +
> > +       sfc->num_chip = 0;
> > +       ret = rockchip_sfc_init(sfc);
> > +       if (ret)
> > +               goto err_irq;
> > +
> > +       pm_runtime_get_noresume(&pdev->dev);
> > +       pm_runtime_set_active(&pdev->dev);
> > +       pm_runtime_enable(&pdev->dev);
> > +       pm_runtime_set_autosuspend_delay(&pdev->dev, 50);
> > +       pm_runtime_use_autosuspend(&pdev->dev);
> > +
> > +       ret = rockchip_sfc_register_all(sfc);
> > +       if (ret)
> > +               goto err_register;
> > +
> > +       clk_disable_unprepare(sfc->clk);
> > +       pm_runtime_put_autosuspend(&pdev->dev);
> > +
> > +       return 0;
> > +
> > +err_register:
> > +       pm_runtime_disable(&pdev->dev);
> > +       pm_runtime_set_suspended(&pdev->dev);
> > +       pm_runtime_put_noidle(&pdev->dev);
> > +err_irq:
> > +       clk_disable_unprepare(sfc->clk);
> > +err_clk:
> > +       clk_disable_unprepare(sfc->hclk);
> > +err_hclk:
> > +       mutex_destroy(&sfc->lock);
> > +       return ret;
> > +}
> > +
> > +static int rockchip_sfc_remove(struct platform_device *pdev)
> > +{
> > +       struct rockchip_sfc *sfc = platform_get_drvdata(pdev);
> > +
> > +       pm_runtime_get_sync(&pdev->dev);
> > +       pm_runtime_disable(&pdev->dev);
> > +       pm_runtime_put_noidle(&pdev->dev);
> > +
> > +       rockchip_sfc_unregister_all(sfc);
> > +       mutex_destroy(&sfc->lock);
> > +       clk_disable_unprepare(sfc->clk);
> > +       clk_disable_unprepare(sfc->hclk);
> > +       return 0;
> > +}
> > +
> > +#ifdef CONFIG_PM
> > +int rockchip_sfc_runtime_suspend(struct device *dev)
> > +{
> > +       struct rockchip_sfc *sfc = dev_get_drvdata(dev);
> > +
> > +       clk_disable_unprepare(sfc->hclk);
> > +       return 0;
> > +}
> > +
> > +int rockchip_sfc_runtime_resume(struct device *dev)
> > +{
> > +       struct rockchip_sfc *sfc = dev_get_drvdata(dev);
> > +
> > +       clk_prepare_enable(sfc->hclk);
> > +       return rockchip_sfc_reset(sfc);
> > +}
> > +#endif /* CONFIG_PM */
> > +
> > +static const struct of_device_id rockchip_sfc_dt_ids[] = {
> > +       { .compatible = "rockchip,sfc"},
> > +       { /* sentinel */ }
> > +};
> > +MODULE_DEVICE_TABLE(of, rockchip_sfc_dt_ids);
> > +
> > +static const struct dev_pm_ops rockchip_sfc_dev_pm_ops = {
> > +       SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
> > +                               pm_runtime_force_resume)
> > +       SET_RUNTIME_PM_OPS(rockchip_sfc_runtime_suspend,
> > +                          rockchip_sfc_runtime_resume, NULL)
> > +};
> > +
> > +static struct platform_driver rockchip_sfc_driver = {
> > +       .driver = {
> > +               .name   = "rockchip-sfc",
> > +               .of_match_table = rockchip_sfc_dt_ids,
> > +               .pm = &rockchip_sfc_dev_pm_ops,
> > +       },
> > +       .probe  = rockchip_sfc_probe,
> > +       .remove = rockchip_sfc_remove,
> > +};
> > +module_platform_driver(rockchip_sfc_driver);
> > +
> > +MODULE_LICENSE("GPL v2");
> > +MODULE_DESCRIPTION("Rockchip Serial Flash Controller Driver");
> > +MODULE_AUTHOR("Shawn Lin <shawn.lin@rock-chips.com>");
> > --
> > 2.7.4
> >
> >
> >
>