[U-Boot] [PATCH v4 30/33] rockchip: Add SPI driver

Jagan Teki
2015-08-28T04:42:59Z

Hi Simon,

On 24 August 2015 at 20:42, Simon Glass <sjg@chromium.org> wrote:
> Add a SPI driver for the Rockchip RK3288, using driver model. It should work
> for other Rockchip SoCs also.
>
> Signed-off-by: Simon Glass <sjg@chromium.org>
> ---
>
> Changes in v4:
> - Rename pinctrl.h to dm/pinctrl.h
>
> Changes in v3: None
> Changes in v2: None
>
> drivers/spi/Kconfig | 9 ++
> drivers/spi/Makefile | 1 +
> drivers/spi/rk_spi.c | 375 +++++++++++++++++++++++++++++++++++++++++++++++++++
> drivers/spi/rk_spi.h | 121 +++++++++++++++++
> 4 files changed, 506 insertions(+)
> create mode 100644 drivers/spi/rk_spi.c
> create mode 100644 drivers/spi/rk_spi.h
>
> diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
> index c84a7b7..87d6571 100644
> --- a/drivers/spi/Kconfig
> +++ b/drivers/spi/Kconfig
> @@ -58,6 +58,15 @@ config ICH_SPI
> access the SPI NOR flash on platforms embedding this Intel
> ICH IP core.
>
> +config ROCKCHIP_SPI
> + bool "Rockchip SPI driver"
> + depends on DM_SPI

It's already in DM_SPI if this is not required, please check.

> + help
> + Enable the Rockchip SPI driver, used to access SPI NOR flash and
> + other SPI peripherals (such as the Chrome OS EC) on Rockchip SoCs.
> + This uses driver model and requires a device tree binding to
> + operate.
> +
> config SANDBOX_SPI
> bool "Sandbox SPI driver"
> depends on SANDBOX && DM
> diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
> index ee88aa1..de241be 100644
> --- a/drivers/spi/Makefile
> +++ b/drivers/spi/Makefile
> @@ -39,6 +39,7 @@ obj-$(CONFIG_MPC8XXX_SPI) += mpc8xxx_spi.o
> obj-$(CONFIG_MXC_SPI) += mxc_spi.o
> obj-$(CONFIG_MXS_SPI) += mxs_spi.o
> obj-$(CONFIG_OMAP3_SPI) += omap3_spi.o
> +obj-$(CONFIG_ROCKCHIP_SPI) += rk_spi.o
> obj-$(CONFIG_SANDBOX_SPI) += sandbox_spi.o
> obj-$(CONFIG_SH_SPI) += sh_spi.o
> obj-$(CONFIG_SH_QSPI) += sh_qspi.o
> diff --git a/drivers/spi/rk_spi.c b/drivers/spi/rk_spi.c
> new file mode 100644
> index 0000000..3ddb9ab
> --- /dev/null
> +++ b/drivers/spi/rk_spi.c
> @@ -0,0 +1,375 @@
> +/*
> + * spi driver for rockchip
> + *
> + * (C) Copyright 2015 Google, Inc
> + *
> + * (C) Copyright 2008-2013 Rockchip Electronics
> + * Peter, Software Engineering, <superpeter.cai@gmail.com>.
> + *
> + * SPDX-License-Identifier: GPL-2.0+
> + */
> +
> +#include <common.h>
> +#include <clk.h>
> +#include <dm.h>
> +#include <errno.h>
> +#include <spi.h>
> +#include <asm/errno.h>
> +#include <asm/io.h>
> +#include <asm/arch/clock.h>
> +#include <asm/arch/periph.h>
> +#include <dm/pinctrl.h>
> +#include "rk_spi.h"
> +
> +DECLARE_GLOBAL_DATA_PTR;
> +
> +struct rockchip_spi_platdata {
> + enum periph_id periph_id;
> + struct udevice *pinctrl;
> + s32 frequency; /* Default clock frequency, -1 for none */
> + fdt_addr_t base;
> + uint deactivate_delay_us; /* Delay to wait after deactivate */
> +};
> +
> +struct rockchip_spi_priv {
> + struct rockchip_spi *regs;
> + struct udevice *clk_gpll;
> + unsigned int max_freq;
> + unsigned int mode;
> + enum periph_id periph_id; /* Peripheral ID for this device */
> + ulong last_transaction_us; /* Time of last transaction end */
> + u8 bits_per_word; /* max 16 bits per word */
> + u8 n_bytes;
> + unsigned int speed_hz;
> + unsigned int tmode;
> + uint input_rate;
> +};
> +
> +#define SPI_FIFO_DEPTH 32
> +
> +static void rkspi_dump_regs(struct rockchip_spi *regs)
> +{
> + debug("RK SPI registers:\n");
> + debug("=================================\n");
> + debug("ctrl0: \t\t0x%08x\n", readl(&regs->ctrlr0));
> + debug("ctrl1: \t\t0x%08x\n", readl(&regs->ctrlr1));
> + debug("ssienr: \t\t0x%08x\n", readl(&regs->enr));
> + debug("ser: \t\t0x%08x\n", readl(&regs->ser));
> + debug("baudr: \t\t0x%08x\n", readl(&regs->baudr));
> + debug("txftlr: \t\t0x%08x\n", readl(&regs->txftlr));
> + debug("rxftlr: \t\t0x%08x\n", readl(&regs->rxftlr));
> + debug("txflr: \t\t0x%08x\n", readl(&regs->txflr));
> + debug("rxflr: \t\t0x%08x\n", readl(&regs->rxflr));
> + debug("sr: \t\t0x%08x\n", readl(&regs->sr));
> + debug("imr: \t\t0x%08x\n", readl(&regs->imr));
> + debug("isr: \t\t0x%08x\n", readl(&regs->isr));
> + debug("dmacr: \t\t0x%08x\n", readl(&regs->dmacr));
> + debug("dmatdlr: \t0x%08x\n", readl(&regs->dmatdlr));
> + debug("dmardlr: \t0x%08x\n", readl(&regs->dmardlr));
> + debug("=================================\n");
> +}
> +
> +static void rkspi_enable_chip(struct rockchip_spi *regs, bool enable)
> +{
> + writel(enable ? 1 : 0, &regs->enr);
> +}
> +
> +static void rkspi_set_clk(struct rockchip_spi_priv *priv, uint speed)
> +{
> + uint clk_div;
> +
> + clk_div = priv->input_rate / speed;
> + clk_div = (clk_div + 1) & 0xfffe;
> + debug("spi speed %u, div %u\n", speed, clk_div);
> +
> + writel(clk_div, &priv->regs->baudr);
> +}
> +
> +static int rkspi_wait_till_not_busy(struct rockchip_spi *regs)
> +{
> + unsigned int delay = 1000;
> +
> + while (delay--) {
> + if (!(readl(&regs->sr) & SR_BUSY))
> + return 0;
> +
> + udelay(1);
> + }
> + debug("RK SPI: Status keeps busy for 1000us after a read/write!\n");
> +
> + return -ETIMEDOUT;
> +}

I just made some comments about, this busy loop and debug prints,
pleas look at [1] it once if you missed.

[1] https://patchwork.ozlabs.org/patch/487873/

> +
> +static void spi_cs_activate(struct rockchip_spi *regs, uint cs)
> +{
> + debug("activate cs%u\n", cs);
> + writel(1 << cs, &regs->ser);
> +}
> +
> +static void spi_cs_deactivate(struct rockchip_spi *regs, uint cs)
> +{
> + debug("deactivate cs%u\n", cs);
> + writel(0, &regs->ser);
> +}
> +
> +static int rockchip_spi_ofdata_to_platdata(struct udevice *bus)
> +{
> + struct rockchip_spi_platdata *plat = bus->platdata;
> + const void *blob = gd->fdt_blob;
> + int node = bus->of_offset;
> + int ret;
> +
> + plat->base = dev_get_addr(bus);
> + ret = uclass_get_device(UCLASS_PINCTRL, 0, &plat->pinctrl);
> + if (ret)
> + return ret;
> + ret = pinctrl_get_periph_id(plat->pinctrl, bus);
> +
> + if (ret < 0) {
> + debug("%s: Could not get peripheral ID for %s: %d\n", __func__,
> + bus->name, ret);
> + return -FDT_ERR_NOTFOUND;
> + }
> + plat->periph_id = ret;
> +
> + plat->frequency = fdtdec_get_int(blob, node, "spi-max-frequency",
> + 50000000);
> + plat->deactivate_delay_us = fdtdec_get_int(blob, node,
> + "spi-deactivate-delay", 0);
> + debug("%s: base=%x, periph_id=%d, max-frequency=%d, deactivate_delay=%d\n",
> + __func__, plat->base, plat->periph_id, plat->frequency,
> + plat->deactivate_delay_us);
> +
> + return 0;
> +}
> +
> +static int rockchip_spi_probe(struct udevice *bus)
> +{
> + struct rockchip_spi_platdata *plat = dev_get_platdata(bus);
> + struct rockchip_spi_priv *priv = dev_get_priv(bus);
> + int ret;
> +
> + debug("%s: probe\n", __func__);
> + priv->regs = (struct rockchip_spi *)plat->base;
> +
> + priv->last_transaction_us = timer_get_us();
> + priv->max_freq = plat->frequency;
> + priv->periph_id = plat->periph_id;
> + ret = uclass_get_device(UCLASS_CLK, CLK_GENERAL, &priv->clk_gpll);
> + if (ret) {
> + debug("%s: Failed to find CLK_GENERAL: %d\n", __func__, ret);
> + return ret;
> + }
> +
> + /*
> + * Use 99 MHz as our clock since it divides nicely into 594 MHz which
> + * is the assumed speed for CLK_GENERAL.
> + */
> + ret = clk_set_periph_rate(priv->clk_gpll, plat->periph_id, 99000000);
> + if (ret < 0) {
> + debug("%s: Failed to set clock: %d\n", __func__, ret);
> + return ret;
> + }
> + priv->input_rate = ret;
> + debug("%s: rate = %u\n", __func__, priv->input_rate);
> + priv->bits_per_word = 8;
> + priv->tmode = TMOD_TR; /* Tx & Rx */
> +
> + return 0;
> +}
> +
> +static int rockchip_spi_claim_bus(struct udevice *dev)
> +{
> + struct udevice *bus = dev->parent;
> + struct rockchip_spi_platdata *plat = dev_get_platdata(bus);
> + struct rockchip_spi_priv *priv = dev_get_priv(bus);
> + struct rockchip_spi *regs = priv->regs;
> + struct dm_spi_slave_platdata *slave_plat = dev_get_parent_platdata(dev);
> + u8 spi_dfs, spi_tf;
> + uint ctrlr0;
> + int ret;
> +
> + /* Disable the SPI hardware */
> + rkspi_enable_chip(regs, 0);
> +
> + switch (priv->bits_per_word) {
> + case 8:
> + priv->n_bytes = 1;
> + spi_dfs = DFS_8BIT;
> + spi_tf = HALF_WORD_OFF;
> + break;
> + case 16:
> + priv->n_bytes = 2;
> + spi_dfs = DFS_16BIT;
> + spi_tf = HALF_WORD_ON;
> + break;
> + default:
> + debug("%s: unsupported bits: %dbits\n", __func__,
> + priv->bits_per_word);
> + return -EPROTONOSUPPORT;
> + }
> +
> + rkspi_set_clk(priv, priv->speed_hz);
> +
> + /* Operation Mode */
> + ctrlr0 = OMOD_MASTER << OMOD_SHIFT;
> +
> + /* Data Frame Size */
> + ctrlr0 |= spi_dfs & DFS_MASK << DFS_SHIFT;
> +
> + /* set SPI mode 0..3 */
> + if (priv->mode & SPI_CPOL)
> + ctrlr0 |= SCOL_HIGH << SCOL_SHIFT;
> + if (priv->mode & SPI_CPHA)
> + ctrlr0 |= SCPH_TOGSTA << SCPH_SHIFT;
> +
> + /* Chip Select Mode */
> + ctrlr0 |= CSM_KEEP << CSM_SHIFT;
> +
> + /* SSN to Sclk_out delay */
> + ctrlr0 |= SSN_DELAY_ONE << SSN_DELAY_SHIFT;
> +
> + /* Serial Endian Mode */
> + ctrlr0 |= SEM_LITTLE << SEM_SHIFT;
> +
> + /* First Bit Mode */
> + ctrlr0 |= FBM_MSB << FBM_SHIFT;
> +
> + /* Byte and Halfword Transform */
> + ctrlr0 |= (spi_tf & HALF_WORD_MASK) << HALF_WORD_TX_SHIFT;
> +
> + /* Rxd Sample Delay */
> + ctrlr0 |= 0 << RXDSD_SHIFT;
> +
> + /* Frame Format */
> + ctrlr0 |= FRF_SPI << FRF_SHIFT;
> +
> + /* Tx and Rx mode */
> + ctrlr0 |= (priv->tmode & TMOD_MASK) << TMOD_SHIFT;
> +
> + writel(ctrlr0, &regs->ctrlr0);
> +
> + ret = pinctrl_request(plat->pinctrl, priv->periph_id, slave_plat->cs);
> + if (ret) {
> + debug("%s: Cannot request pinctrl: %d\n", __func__, ret);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int rockchip_spi_release_bus(struct udevice *dev)
> +{
> + return 0;
> +}
> +
> +static int rockchip_spi_xfer(struct udevice *dev, unsigned int bitlen,
> + const void *dout, void *din, unsigned long flags)
> +{
> + struct udevice *bus = dev->parent;
> + struct rockchip_spi_priv *priv = dev_get_priv(bus);
> + struct rockchip_spi *regs = priv->regs;
> + struct dm_spi_slave_platdata *slave_plat = dev_get_parent_platdata(dev);
> + int len = bitlen >> 3;
> + const u8 *out = dout;
> + u8 *in = din;
> + int toread, towrite;
> + int ret;
> +
> + debug("%s: dout=%p, din=%p, len=%x, flags=%lx\n", __func__, dout, din,
> + len, flags);
> + if (0)
> + rkspi_dump_regs(regs);
> +
> + /* Assert CS before transfer */
> + if (flags & SPI_XFER_BEGIN)
> + spi_cs_activate(regs, slave_plat->cs);
> +
> + while (len > 0) {
> + int todo = min(len, 0xffff);
> +
> + rkspi_enable_chip(regs, true);
> + writel(todo - 1, &regs->ctrlr1);
> + rkspi_enable_chip(regs, true);
> +
> + toread = todo;
> + towrite = todo;
> + while (toread || towrite) {
> + u32 status = readl(&regs->sr);
> +
> + if (towrite && !(status & SR_TF_FULL)) {
> + writel(out ? *out++ : 0, regs->txdr);
> + towrite--;
> + }
> + if (toread && !(status & SR_RF_EMPT)) {
> + u32 byte = readl(regs->rxdr);
> +
> + if (in)
> + *in++ = byte;
> + toread--;
> + }
> + }
> + ret = rkspi_wait_till_not_busy(regs);
> + if (ret)
> + break;
> + len -= todo;
> + }
> +
> + /* Deassert CS after transfer */
> + if (flags & SPI_XFER_END)
> + spi_cs_deactivate(regs, slave_plat->cs);
> +
> + rkspi_enable_chip(regs, false);
> +
> + return ret;
> +}
> +
> +static int rockchip_spi_set_speed(struct udevice *bus, uint speed)
> +{
> + struct rockchip_spi_priv *priv = dev_get_priv(bus);
> +
> + if (speed > 48000000)
> + return -EINVAL;
> + if (speed > priv->max_freq)
> + speed = priv->max_freq;
> + priv->speed_hz = speed;
> +
> + return 0;
> +}
> +
> +static int rockchip_spi_set_mode(struct udevice *bus, uint mode)
> +{
> + struct rockchip_spi_priv *priv = dev_get_priv(bus);
> +
> + priv->mode = mode;
> +
> + return 0;
> +}
> +
> +static const struct dm_spi_ops rockchip_spi_ops = {
> + .claim_bus = rockchip_spi_claim_bus,
> + .release_bus = rockchip_spi_release_bus,
> + .xfer = rockchip_spi_xfer,
> + .set_speed = rockchip_spi_set_speed,
> + .set_mode = rockchip_spi_set_mode,
> + /*
> + * cs_info is not needed, since we require all chip selects to be
> + * in the device tree explicitly
> + */
> +};
> +
> +static const struct udevice_id rockchip_spi_ids[] = {
> + { .compatible = "rockchip,rk3288-spi" },
> + { }
> +};
> +
> +U_BOOT_DRIVER(rockchip_spi) = {
> + .name = "rockchip_spi",
> + .id = UCLASS_SPI,
> + .of_match = rockchip_spi_ids,
> + .ops = &rockchip_spi_ops,
> + .ofdata_to_platdata = rockchip_spi_ofdata_to_platdata,
> + .platdata_auto_alloc_size = sizeof(struct rockchip_spi_platdata),
> + .priv_auto_alloc_size = sizeof(struct rockchip_spi_priv),
> + .probe = rockchip_spi_probe,
> +};
> diff --git a/drivers/spi/rk_spi.h b/drivers/spi/rk_spi.h
> new file mode 100644
> index 0000000..bfb1739
> --- /dev/null
> +++ b/drivers/spi/rk_spi.h
> @@ -0,0 +1,121 @@
> +/*
> + * SPI driver for rockchip
> + *
> + * (C) Copyright 2015 Google, Inc
> + *
> + * (C) Copyright 2008-2013 Rockchip Electronics
> + * Peter, Software Engineering, <superpeter.cai@gmail.com>.
> + *
> + * SPDX-License-Identifier: GPL-2.0+
> + */
> +
> +#ifndef __RK_SPI_H
> +#define __RK_SPI_H
> +
> +struct rockchip_spi {
> + u32 ctrlr0;
> + u32 ctrlr1;
> + u32 enr;
> + u32 ser;
> + u32 baudr;
> + u32 txftlr;
> + u32 rxftlr;
> + u32 txflr;
> + u32 rxflr;
> + u32 sr;
> + u32 ipr;
> + u32 imr;
> + u32 isr;
> + u32 risr;
> + u32 icr;
> + u32 dmacr;
> + u32 dmatdlr;
> + u32 dmardlr; /* 0x44 */
> + u32 reserved[0xef];
> + u32 txdr[0x100]; /* 0x400 */
> + u32 rxdr[0x100]; /* 0x800 */
> +};
> +
> +/* CTRLR0 */
> +enum {
> + DFS_SHIFT = 0, /* Data Frame Size */
> + DFS_MASK = 3,
> + DFS_4BIT = 0,
> + DFS_8BIT,
> + DFS_16BIT,
> + DFS_RESV,
> +
> + CFS_SHIFT = 2, /* Control Frame Size */
> + CFS_MASK = 0xf,
> +
> + SCPH_SHIFT = 6, /* Serial Clock Phase */
> + SCPH_MASK = 1,
> + SCPH_TOGMID = 0, /* SCLK toggles in middle of first data bit */
> + SCPH_TOGSTA, /* SCLK toggles at start of first data bit */
> +
> + SCOL_SHIFT = 7, /* Serial Clock Polarity */
> + SCOL_MASK = 1,
> + SCOL_LOW = 0, /* Inactive state of serial clock is low */
> + SCOL_HIGH, /* Inactive state of serial clock is high */
> +
> + CSM_SHIFT = 8, /* Chip Select Mode */
> + CSM_MASK = 0x3,
> + CSM_KEEP = 0, /* ss_n stays low after each frame */
> + CSM_HALF, /* ss_n high for half sclk_out cycles */
> + CSM_ONE, /* ss_n high for one sclk_out cycle */
> + CSM_RESV,
> +
> + SSN_DELAY_SHIFT = 10, /* SSN to Sclk_out delay */
> + SSN_DELAY_MASK = 1,
> + SSN_DELAY_HALF = 0, /* 1/2 sclk_out cycle */
> + SSN_DELAY_ONE = 1, /* 1 sclk_out cycle */
> +
> + SEM_SHIFT = 11, /* Serial Endian Mode */
> + SEM_MASK = 1,
> + SEM_LITTLE = 0, /* little endian */
> + SEM_BIG, /* big endian */
> +
> + FBM_SHIFT = 12, /* First Bit Mode */
> + FBM_MASK = 1,
> + FBM_MSB = 0, /* first bit is MSB */
> + FBM_LSB, /* first bit in LSB */
> +
> + HALF_WORD_TX_SHIFT = 13, /* Byte and Halfword Transform */
> + HALF_WORD_MASK = 1,
> + HALF_WORD_ON = 0, /* apb 16bit write/read, spi 8bit write/read */
> + HALF_WORD_OFF, /* apb 8bit write/read, spi 8bit write/read */
> +
> + RXDSD_SHIFT = 14, /* Rxd Sample Delay, in cycles */
> + RXDSD_MASK = 3,
> +
> + FRF_SHIFT = 16, /* Frame Format */
> + FRF_MASK = 3,
> + FRF_SPI = 0, /* Motorola SPI */
> + FRF_SSP, /* Texas Instruments SSP*/
> + FRF_MICROWIRE, /* National Semiconductors Microwire */
> + FRF_RESV,
> +
> + TMOD_SHIFT = 18, /* Transfer Mode */
> + TMOD_MASK = 3,
> + TMOD_TR = 0, /* xmit & recv */
> + TMOD_TO, /* xmit only */
> + TMOD_RO, /* recv only */
> + TMOD_RESV,
> +
> + OMOD_SHIFT = 20, /* Operation Mode */
> + OMOD_MASK = 1,
> + OMOD_MASTER = 0, /* Master Mode */
> + OMOD_SLAVE, /* Slave Mode */
> +};
> +
> +/* SR */
> +enum {
> + SR_MASK = 0x7f,
> + SR_BUSY = 1 << 0,
> + SR_TF_FULL = 1 << 1,
> + SR_TF_EMPT = 1 << 2,
> + SR_RF_EMPT = 1 << 3,
> + SR_RF_FULL = 1 << 4,
> +};
> +
> +#endif /* __RK_SPI_H */
> --
> 2.5.0.457.gab17608

thanks!
--
Jagan | openedev.