[U-Boot] [PATCH 01/11] spi: davinci_spi: Convert to driver to adapt to DM

Simon Glass sjg at chromium.org
Wed Apr 20 16:40:35 CEST 2016


On 12 April 2016 at 05:33, Vignesh R <vigneshr at ti.com> wrote:
> Convert davinci_spi driver to comply with SPI DM framework.
>
> Signed-off-by: Vignesh R <vigneshr at ti.com>
> ---
>  drivers/spi/davinci_spi.c | 326 +++++++++++++++++++++++++++++++++-------------
>  1 file changed, 237 insertions(+), 89 deletions(-)
>
> diff --git a/drivers/spi/davinci_spi.c b/drivers/spi/davinci_spi.c
> index 0bd4f88926f1..838f9fb7fb27 100644
> --- a/drivers/spi/davinci_spi.c
> +++ b/drivers/spi/davinci_spi.c
> @@ -14,6 +14,7 @@
>  #include <malloc.h>
>  #include <asm/io.h>
>  #include <asm/arch/hardware.h>
> +#include <dm.h>
>
>  /* SPIGCR0 */
>  #define SPIGCR0_SPIENA_MASK    0x1
> @@ -51,6 +52,7 @@
>  /* SPIDEF */
>  #define SPIDEF_CSDEF0_MASK     BIT(0)
>
> +#ifndef CONFIG_DM_SPI
>  #define SPI0_BUS               0
>  #define SPI0_BASE              CONFIG_SYS_SPI_BASE
>  /*
> @@ -83,6 +85,9 @@
>  #define SPI2_NUM_CS            CONFIG_SYS_SPI2_NUM_CS
>  #define SPI2_BASE              CONFIG_SYS_SPI2_BASE
>  #endif
> +#endif
> +
> +DECLARE_GLOBAL_DATA_PTR;
>
>  /* davinci spi register set */
>  struct davinci_spi_regs {
> @@ -114,16 +119,17 @@ struct davinci_spi_regs {
>
>  /* davinci spi slave */
>  struct davinci_spi_slave {
> +#ifndef CONFIG_DM_SPI
>         struct spi_slave slave;
> +#endif
>         struct davinci_spi_regs *regs;
>         unsigned int freq;
> +       unsigned int mode;
> +       u8 num_cs;
> +       u8 cur_cs;
> +       bool half_duplex;

Comments on these?

>  };
>
> -static inline struct davinci_spi_slave *to_davinci_spi(struct spi_slave *slave)
> -{
> -       return container_of(slave, struct davinci_spi_slave, slave);
> -}
> -
>  /*
>   * This functions needs to act like a macro to avoid pipeline reloads in the
>   * loops below. Use always_inline. This gains us about 160KiB/s and the bloat
> @@ -144,15 +150,14 @@ static inline u32 davinci_spi_xfer_data(struct davinci_spi_slave *ds, u32 data)
>         return buf_reg_val;
>  }
>
> -static int davinci_spi_read(struct spi_slave *slave, unsigned int len,
> +static int davinci_spi_read(struct davinci_spi_slave *ds, unsigned int len,
>                             u8 *rxp, unsigned long flags)
>  {
> -       struct davinci_spi_slave *ds = to_davinci_spi(slave);
>         unsigned int data1_reg_val;
>
>         /* enable CS hold, CS[n] and clear the data bits */
>         data1_reg_val = ((1 << SPIDAT1_CSHOLD_SHIFT) |
> -                        (slave->cs << SPIDAT1_CSNR_SHIFT));
> +                        (ds->cur_cs << SPIDAT1_CSNR_SHIFT));
>
>         /* wait till TXFULL is deasserted */
>         while (readl(&ds->regs->buf) & SPIBUF_TXFULL_MASK)
> @@ -175,15 +180,14 @@ static int davinci_spi_read(struct spi_slave *slave, unsigned int len,
>         return 0;
>  }
>
> -static int davinci_spi_write(struct spi_slave *slave, unsigned int len,
> +static int davinci_spi_write(struct davinci_spi_slave *ds, unsigned int len,
>                              const u8 *txp, unsigned long flags)
>  {
> -       struct davinci_spi_slave *ds = to_davinci_spi(slave);
>         unsigned int data1_reg_val;
>
>         /* enable CS hold and clear the data bits */
>         data1_reg_val = ((1 << SPIDAT1_CSHOLD_SHIFT) |
> -                        (slave->cs << SPIDAT1_CSNR_SHIFT));
> +                        (ds->cur_cs << SPIDAT1_CSNR_SHIFT));
>
>         /* wait till TXFULL is deasserted */
>         while (readl(&ds->regs->buf) & SPIBUF_TXFULL_MASK)
> @@ -209,16 +213,15 @@ static int davinci_spi_write(struct spi_slave *slave, unsigned int len,
>         return 0;
>  }
>
> -#ifndef CONFIG_SPI_HALF_DUPLEX
> -static int davinci_spi_read_write(struct spi_slave *slave, unsigned int len,
> -                                 u8 *rxp, const u8 *txp, unsigned long flags)
> +static int davinci_spi_read_write(struct davinci_spi_slave *ds, unsigned
> +                                 int len, u8 *rxp, const u8 *txp,
> +                                 unsigned long flags)
>  {
> -       struct davinci_spi_slave *ds = to_davinci_spi(slave);
>         unsigned int data1_reg_val;
>
>         /* enable CS hold and clear the data bits */
>         data1_reg_val = ((1 << SPIDAT1_CSHOLD_SHIFT) |
> -                        (slave->cs << SPIDAT1_CSNR_SHIFT));
> +                        (ds->cur_cs << SPIDAT1_CSNR_SHIFT));
>
>         /* wait till TXFULL is deasserted */
>         while (readl(&ds->regs->buf) & SPIBUF_TXFULL_MASK)
> @@ -237,7 +240,115 @@ static int davinci_spi_read_write(struct spi_slave *slave, unsigned int len,
>
>         return 0;
>  }
> -#endif
> +
> +
> +static int __davinci_spi_claim_bus(struct davinci_spi_slave *ds, int cs)
> +{
> +       unsigned int mode = 0, scalar;
> +
> +       /* Enable the SPI hardware */
> +       writel(SPIGCR0_SPIRST_MASK, &ds->regs->gcr0);
> +       udelay(1000);
> +       writel(SPIGCR0_SPIENA_MASK, &ds->regs->gcr0);
> +
> +       /* Set master mode, powered up and not activated */
> +       writel(SPIGCR1_MASTER_MASK | SPIGCR1_CLKMOD_MASK, &ds->regs->gcr1);
> +
> +       /* CS, CLK, SIMO and SOMI are functional pins */
> +       writel(((1 << cs) | SPIPC0_CLKFUN_MASK |
> +               SPIPC0_DOFUN_MASK | SPIPC0_DIFUN_MASK), &ds->regs->pc0);
> +
> +       /* setup format */
> +       scalar = ((CONFIG_SYS_SPI_CLK / ds->freq) - 1) & 0xFF;
> +
> +       /*
> +        * Use following format:
> +        *   character length = 8,
> +        *   MSB shifted out first
> +        */
> +       if (ds->mode & SPI_CPOL)
> +               mode |= SPI_CPOL;
> +       if (!(ds->mode & SPI_CPHA))
> +               mode |= SPI_CPHA;
> +       writel(8 | (scalar << SPIFMT_PRESCALE_SHIFT) |
> +               (mode << SPIFMT_PHASE_SHIFT), &ds->regs->fmt0);
> +
> +       /*
> +        * Including a minor delay. No science here. Should be good even with
> +        * no delay
> +        */
> +       writel((50 << SPI_C2TDELAY_SHIFT) |
> +               (50 << SPI_T2CDELAY_SHIFT), &ds->regs->delay);
> +
> +       /* default chip select register */
> +       writel(SPIDEF_CSDEF0_MASK, &ds->regs->def);
> +
> +       /* no interrupts */
> +       writel(0, &ds->regs->int0);
> +       writel(0, &ds->regs->lvl);
> +
> +       /* enable SPI */
> +       writel((readl(&ds->regs->gcr1) | SPIGCR1_SPIENA_MASK), &ds->regs->gcr1);
> +
> +       return 0;
> +}
> +
> +static int __davinci_spi_release_bus(struct davinci_spi_slave *ds)
> +{
> +       /* Disable the SPI hardware */
> +       writel(SPIGCR0_SPIRST_MASK, &ds->regs->gcr0);
> +
> +       return 0;
> +}
> +
> +static int __davinci_spi_xfer(struct davinci_spi_slave *ds,
> +               unsigned int bitlen,  const void *dout, void *din,
> +               unsigned long flags)
> +{
> +       unsigned int len;
> +
> +       if (bitlen == 0)
> +               /* Finish any previously submitted transfers */
> +               goto out;
> +
> +       /*
> +        * It's not clear how non-8-bit-aligned transfers are supposed to be
> +        * represented as a stream of bytes...this is a limitation of
> +        * the current SPI interface - here we terminate on receiving such a
> +        * transfer request.
> +        */
> +       if (bitlen % 8) {
> +               /* Errors always terminate an ongoing transfer */
> +               flags |= SPI_XFER_END;
> +               goto out;
> +       }
> +
> +       len = bitlen / 8;
> +
> +       if (!dout)
> +               return davinci_spi_read(ds, len, din, flags);
> +       if (!din)
> +               return davinci_spi_write(ds, len, dout, flags);
> +       if (!ds->half_duplex)
> +               return davinci_spi_read_write(ds, len, din, dout, flags);
> +
> +       printf("SPI full duplex not supported\n");
> +       flags |= SPI_XFER_END;
> +
> +out:
> +       if (flags & SPI_XFER_END) {
> +               u8 dummy = 0;
> +               davinci_spi_write(ds, 1, &dummy, flags);
> +       }
> +       return 0;
> +}
> +
> +#ifndef CONFIG_DM_SPI
> +
> +static inline struct davinci_spi_slave *to_davinci_spi(struct spi_slave *slave)
> +{
> +       return container_of(slave, struct davinci_spi_slave, slave);
> +}
>
>  int spi_cs_is_valid(unsigned int bus, unsigned int cs)
>  {
> @@ -313,6 +424,7 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
>         }
>
>         ds->freq = max_hz;
> +       ds->mode = mode;
>
>         return &ds->slave;
>  }
> @@ -324,104 +436,140 @@ void spi_free_slave(struct spi_slave *slave)
>         free(ds);
>  }
>
> +int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
> +            const void *dout, void *din, unsigned long flags)
> +{
> +       struct davinci_spi_slave *ds = to_davinci_spi(slave);
> +
> +       ds->cur_cs = slave->cs;
> +
> +       return __davinci_spi_xfer(ds, bitlen, dout, din, flags);
> +}
> +
>  int spi_claim_bus(struct spi_slave *slave)
>  {
>         struct davinci_spi_slave *ds = to_davinci_spi(slave);
> -       unsigned int scalar;
>
> -       /* Enable the SPI hardware */
> -       writel(SPIGCR0_SPIRST_MASK, &ds->regs->gcr0);
> -       udelay(1000);
> -       writel(SPIGCR0_SPIENA_MASK, &ds->regs->gcr0);
> +#ifdef CONFIG_SPI_HALF_DUPLEX
> +       ds->half_duplex = true;
> +#else
> +       ds->half_duplex = false;
> +#endif
> +       return __davinci_spi_claim_bus(ds, ds->slave.cs);
> +}
>
> -       /* Set master mode, powered up and not activated */
> -       writel(SPIGCR1_MASTER_MASK | SPIGCR1_CLKMOD_MASK, &ds->regs->gcr1);
> +void spi_release_bus(struct spi_slave *slave)
> +{
> +       struct davinci_spi_slave *ds = to_davinci_spi(slave);
>
> -       /* CS, CLK, SIMO and SOMI are functional pins */
> -       writel(((1 << slave->cs) | SPIPC0_CLKFUN_MASK |
> -               SPIPC0_DOFUN_MASK | SPIPC0_DIFUN_MASK), &ds->regs->pc0);
> +       __davinci_spi_release_bus(ds);
> +}
>
> -       /* setup format */
> -       scalar = ((CONFIG_SYS_SPI_CLK / ds->freq) - 1) & 0xFF;
> +#else
> +static int davinci_spi_set_speed(struct udevice *bus, uint max_hz)
> +{
> +       struct davinci_spi_slave *ds = dev_get_priv(bus);
>
> -       /*
> -        * Use following format:
> -        *   character length = 8,
> -        *   clock signal delayed by half clk cycle,
> -        *   clock low in idle state - Mode 0,
> -        *   MSB shifted out first
> -        */
> -       writel(8 | (scalar << SPIFMT_PRESCALE_SHIFT) |
> -               (1 << SPIFMT_PHASE_SHIFT), &ds->regs->fmt0);
> +       debug("%s speed %u\n", __func__, max_hz);
> +       if (max_hz > CONFIG_SYS_SPI_CLK / 2)
> +               return -EINVAL;
>
> -       /*
> -        * Including a minor delay. No science here. Should be good even with
> -        * no delay
> -        */
> -       writel((50 << SPI_C2TDELAY_SHIFT) |
> -               (50 << SPI_T2CDELAY_SHIFT), &ds->regs->delay);
> +       ds->freq = max_hz;
>
> -       /* default chip select register */
> -       writel(SPIDEF_CSDEF0_MASK, &ds->regs->def);
> +       return 0;
> +}
>
> -       /* no interrupts */
> -       writel(0, &ds->regs->int0);
> -       writel(0, &ds->regs->lvl);
> +static int davinci_spi_set_mode(struct udevice *bus, uint mode)
> +{
> +       struct davinci_spi_slave *ds = dev_get_priv(bus);
>
> -       /* enable SPI */
> -       writel((readl(&ds->regs->gcr1) | SPIGCR1_SPIENA_MASK), &ds->regs->gcr1);
> +       debug("%s mode %u\n", __func__, mode);
> +       ds->mode = mode;
>
>         return 0;
>  }
>
> -void spi_release_bus(struct spi_slave *slave)
> +static int davinci_spi_claim_bus(struct udevice *dev)
>  {
> -       struct davinci_spi_slave *ds = to_davinci_spi(slave);
> +       struct dm_spi_slave_platdata *slave_plat =
> +               dev_get_parent_platdata(dev);
> +       struct udevice *bus = dev->parent;
> +       struct davinci_spi_slave *ds = dev_get_priv(bus);
> +
> +       if (slave_plat->cs >= ds->num_cs) {

What is going on here? Why would these be different?

> +               printf("Invalid SPI chipselect\n");
> +               return -EINVAL;
> +       }
> +       ds->half_duplex = slave_plat->mode & SPI_PREAMBLE;
>
> -       /* Disable the SPI hardware */
> -       writel(SPIGCR0_SPIRST_MASK, &ds->regs->gcr0);
> +       return __davinci_spi_claim_bus(ds, slave_plat->cs);
>  }
>
> -int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
> -            const void *dout, void *din, unsigned long flags)
> +static int davinci_spi_release_bus(struct udevice *dev)
>  {
> -       unsigned int len;
> +       struct davinci_spi_slave *ds = dev_get_priv(dev->parent);
>
> -       if (bitlen == 0)
> -               /* Finish any previously submitted transfers */
> -               goto out;
> +       return __davinci_spi_release_bus(ds);
> +}
>
> -       /*
> -        * It's not clear how non-8-bit-aligned transfers are supposed to be
> -        * represented as a stream of bytes...this is a limitation of
> -        * the current SPI interface - here we terminate on receiving such a
> -        * transfer request.
> -        */
> -       if (bitlen % 8) {
> -               /* Errors always terminate an ongoing transfer */
> -               flags |= SPI_XFER_END;
> -               goto out;
> +static int davinci_spi_xfer(struct udevice *dev, unsigned int bitlen,
> +                           const void *dout, void *din,
> +                           unsigned long flags)
> +{
> +       struct dm_spi_slave_platdata *slave =
> +               dev_get_parent_platdata(dev);
> +       struct udevice *bus = dev->parent;
> +       struct davinci_spi_slave *ds = dev_get_priv(bus);
> +
> +       if (slave->cs >= ds->num_cs) {
> +               printf("Invalid SPI chipselect\n");
> +               return -EINVAL;
>         }
> +       ds->cur_cs = slave->cs;
>
> -       len = bitlen / 8;
> +       return __davinci_spi_xfer(ds, bitlen, dout, din, flags);
> +}
>
> -       if (!dout)
> -               return davinci_spi_read(slave, len, din, flags);
> -       else if (!din)
> -               return davinci_spi_write(slave, len, dout, flags);
> -#ifndef CONFIG_SPI_HALF_DUPLEX
> -       else
> -               return davinci_spi_read_write(slave, len, din, dout, flags);
> -#else
> -       printf("SPI full duplex transaction requested with "
> -              "CONFIG_SPI_HALF_DUPLEX defined.\n");
> -       flags |= SPI_XFER_END;
> -#endif
> +static int davinci_spi_probe(struct udevice *bus)
> +{
> +       /* Nothing to do */
> +       return 0;
> +}
> +
> +static int davinci_ofdata_to_platadata(struct udevice *bus)
> +{
> +       struct davinci_spi_slave *ds = dev_get_priv(bus);
> +       const void *blob = gd->fdt_blob;
> +       int node = bus->of_offset;
> +
> +       ds->regs = map_physmem(dev_get_addr(bus),
> +                       sizeof(struct davinci_spi_regs), MAP_NOCACHE);

Can you add a dev_map_physmem() to do this in one step?

> +       ds->num_cs = fdtdec_get_int(blob, node, "num-cs", 4);
>
> -out:
> -       if (flags & SPI_XFER_END) {
> -               u8 dummy = 0;
> -               davinci_spi_write(slave, 1, &dummy, flags);
> -       }
>         return 0;
>  }
> +
> +static const struct dm_spi_ops davinci_spi_ops = {
> +       .claim_bus      = davinci_spi_claim_bus,
> +       .release_bus    = davinci_spi_release_bus,
> +       .xfer           = davinci_spi_xfer,
> +       .set_speed      = davinci_spi_set_speed,
> +       .set_mode       = davinci_spi_set_mode,
> +};
> +
> +static const struct udevice_id davinci_spi_ids[] = {
> +       { .compatible = "ti,keystone-spi" },
> +       { .compatible = "ti,dm6441-spi" },
> +       { }
> +};
> +
> +U_BOOT_DRIVER(davinci_spi) = {
> +       .name = "davinci_spi",
> +       .id = UCLASS_SPI,
> +       .of_match = davinci_spi_ids,
> +       .ops = &davinci_spi_ops,
> +       .ofdata_to_platdata = davinci_ofdata_to_platadata,
> +       .priv_auto_alloc_size = sizeof(struct davinci_spi_slave),
> +       .probe = davinci_spi_probe,
> +};
> +#endif
> --
> 2.8.1
>

Regards,
Simon


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