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

Simon Glass
2016-04-20T14:40:35Z

On 12 April 2016 at 05:33, Vignesh R <vigneshr@ti.com> wrote:
> Convert davinci_spi driver to comply with SPI DM framework.
>
> Signed-off-by: Vignesh R <vigneshr@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