[U-Boot] [PATCH v5 29/41] rockchip: Add SPI driver
Simon Glass
sjg at chromium.org
Wed Sep 2 03:03:58 CEST 2015
Hi Jagan,
On 31 August 2015 at 23:23, Jagan Teki <jteki at openedev.com> wrote:
> On 31 August 2015 at 04:25, Simon Glass <sjg at 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 at chromium.org>
>> ---
>>
>> Changes in v5:
>> - Drop unnecessary 'depends on DM_SPI' in Kconfig
>> - Tidy up rkspi_dump_regs() debug output
>> - Tidy up the delay in rkspi_wait_till_not_busy()
>>
>> Changes in v4:
>> - Rename pinctrl.h to dm/pinctrl.h
>>
>> Changes in v3: None
>> Changes in v2: None
>>
>> drivers/spi/Kconfig | 8 ++
>> drivers/spi/Makefile | 1 +
>> drivers/spi/rk_spi.c | 372 +++++++++++++++++++++++++++++++++++++++++++++++++++
>> drivers/spi/rk_spi.h | 121 +++++++++++++++++
>> 4 files changed, 502 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..8e04fce 100644
>> --- a/drivers/spi/Kconfig
>> +++ b/drivers/spi/Kconfig
>> @@ -58,6 +58,14 @@ config ICH_SPI
>> access the SPI NOR flash on platforms embedding this Intel
>> ICH IP core.
>>
>> +config ROCKCHIP_SPI
>> + bool "Rockchip SPI driver"
>> + 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..46b1a37
>> --- /dev/null
>> +++ b/drivers/spi/rk_spi.c
>> @@ -0,0 +1,372 @@
>> +/*
>> + * spi driver for rockchip
>> + *
>> + * (C) Copyright 2015 Google, Inc
>> + *
>> + * (C) Copyright 2008-2013 Rockchip Electronics
>> + * Peter, Software Engineering, <superpeter.cai at 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"
>
> Please move the header file data here
I would prefer to keep the declarations separate. They are not needed
in order to understand this code, and in fact just clutter it up. This
pattern is used widely in U-Boot and Linux.
>
>> +
>> +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("ctrl0: \t\t0x%08x\n", readl(®s->ctrlr0));
>> + debug("ctrl1: \t\t0x%08x\n", readl(®s->ctrlr1));
>> + debug("ssienr: \t\t0x%08x\n", readl(®s->enr));
>> + debug("ser: \t\t0x%08x\n", readl(®s->ser));
>> + debug("baudr: \t\t0x%08x\n", readl(®s->baudr));
>> + debug("txftlr: \t\t0x%08x\n", readl(®s->txftlr));
>> + debug("rxftlr: \t\t0x%08x\n", readl(®s->rxftlr));
>> + debug("txflr: \t\t0x%08x\n", readl(®s->txflr));
>> + debug("rxflr: \t\t0x%08x\n", readl(®s->rxflr));
>> + debug("sr: \t\t0x%08x\n", readl(®s->sr));
>> + debug("imr: \t\t0x%08x\n", readl(®s->imr));
>> + debug("isr: \t\t0x%08x\n", readl(®s->isr));
>> + debug("dmacr: \t\t0x%08x\n", readl(®s->dmacr));
>> + debug("dmatdlr: \t0x%08x\n", readl(®s->dmatdlr));
>> + debug("dmardlr: \t0x%08x\n", readl(®s->dmardlr));
>> +}
>> +
>> +static void rkspi_enable_chip(struct rockchip_spi *regs, bool enable)
>> +{
>> + writel(enable ? 1 : 0, ®s->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;
>
> Define a clk divisor macro.
OK done.
>
>> + 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 long start;
>> +
>> + start = get_timer(0);
>> + while (readl(®s->sr) & SR_BUSY) {
>> + if (get_timer(start) > 1000) {
>
> Define macro similar to CONFIG_SYS_ROCKCHIP_SPI_WAIT
OK done
>
>> + debug("RK SPI: Status keeps busy for 1000us after a read/write!\n");
>> + return -ETIMEDOUT;
>> + }
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static void spi_cs_activate(struct rockchip_spi *regs, uint cs)
>> +{
>> + debug("activate cs%u\n", cs);
>> + writel(1 << cs, ®s->ser);
>> +}
>> +
>> +static void spi_cs_deactivate(struct rockchip_spi *regs, uint cs)
>> +{
>> + debug("deactivate cs%u\n", cs);
>> + writel(0, ®s->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, ®s->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);
>
> if (0) is really needed?
I'll change it to use #ifdef above.
>
>> +
>> + /* 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, ®s->ctrlr1);
>> + rkspi_enable_chip(regs, true);
>> +
>> + toread = todo;
>> + towrite = todo;
>> + while (toread || towrite) {
>> + u32 status = readl(®s->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)
>
> Comment or macro for this numerical.
OK done.
>
>> + 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,
>> +};
[snip]
Regards,
Simon
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