[U-Boot] [PATCH v4] spi: Add support SH Quad SPI driver

Jagan Teki
2013-10-03T19:45:55Z

Hi Nobuhiro Iwamatsu,

I have send your patch for v4.
Eliminated few checks see on change log:

Please fix below comments and try to apply the same on u-boot-spi.git
repo with master-probe branch.

On Fri, Oct 4, 2013 at 1:04 AM, Jagannadha Sutradharudu Teki
<jagannadha.sutradharudu-teki@xilinx.com> wrote:
> From: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
>
> This patch adds a driver for Renesas SoC's Quad SPI bus.
> This supports with 8 bits per transfer to use with SPI flash.
>
> Signed-off-by: Kouei Abe <kouei.abe.cp@renesas.com>
> Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
> Signed-off-by: Jagannadha Sutradharudu Teki <jaganna@xilinx.com>
> ---
>
> Changes for v4:
> - Added tabs
> - Added comments
> - Added sh_qspi_init()
> Changes for v3:
> - Change Queued to Quad.
> - Remove path of file from file header.
> - Use read* and write* directly instead of sh_qspi_write* sh_qspi_read*.
> - Change driver format.
> Changes for v2:
> - "SH QSPI" to "SH QSPI (Queued SPI)".
> - Remove magic number.
>
> drivers/spi/Makefile | 1 +
> drivers/spi/sh_qspi.c | 248 ++++++++++++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 249 insertions(+)
> create mode 100644 drivers/spi/sh_qspi.c
>
> diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
> index 91d24ce..c44f851 100644
> --- a/drivers/spi/Makefile
> +++ b/drivers/spi/Makefile
> @@ -33,6 +33,7 @@ COBJS-$(CONFIG_OC_TINY_SPI) += oc_tiny_spi.o
> COBJS-$(CONFIG_OMAP3_SPI) += omap3_spi.o
> COBJS-$(CONFIG_SOFT_SPI) += soft_spi.o
> COBJS-$(CONFIG_SH_SPI) += sh_spi.o
> +COBJS-$(CONFIG_SH_QSPI) += sh_qspi.o
> COBJS-$(CONFIG_FSL_ESPI) += fsl_espi.o
> COBJS-$(CONFIG_FDT_SPI) += fdt_spi.o
> COBJS-$(CONFIG_TEGRA20_SFLASH) += tegra20_sflash.o
> diff --git a/drivers/spi/sh_qspi.c b/drivers/spi/sh_qspi.c
> new file mode 100644
> index 0000000..6872142
> --- /dev/null
> +++ b/drivers/spi/sh_qspi.c
> @@ -0,0 +1,248 @@
> +/*
> + * SH QSPI (Quad SPI) driver
> + *
> + * Copyright (C) 2013 Renesas Electronics Corporation
> + * Copyright (C) 2013 Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
> + *
> + * SPDX-License-Identifier: GPL-2.0
> + */
> +
> +#include <common.h>
> +#include <malloc.h>
> +#include <spi.h>
> +#include <asm/io.h>
> +
> +/* SH QSPI register bit masks <REG>_<BIT> */
> +#define SPCR_MSTR 0x08
> +#define SPCR_SPE 0x40
> +#define SPSR_SPRFF 0x80
> +#define SPSR_SPTEF 0x20
> +#define SPPCR_IO3FV 0x04
> +#define SPPCR_IO2FV 0x02
> +#define SPPCR_IO1FV 0x01
> +#define SPBDCR_RXBC0 (1 << 0)
> +#define SPCMD_SCKDEN (1 << 15)
> +#define SPCMD_SLNDEN (1 << 14)
> +#define SPCMD_SPNDEN (1 << 13)
> +#define SPCMD_SSLKP (1 << 7)
> +#define SPCMD_BRDV0 (1 << 2)
> +#define SPCMD_INIT1 SPCMD_SCKDEN | SPCMD_SLNDEN | \
> + SPCMD_SPNDEN | SPCMD_SSLKP | \
> + SPCMD_BRDV0
> +#define SPCMD_INIT2 SPCMD_SPNDEN | SPCMD_SSLKP | \
> + SPCMD_BRDV0
> +#define SPBFCR_TXRST (1 << 7)
> +#define SPBFCR_RXRST (1 << 6)
> +
> +/* SH QSPI register set */
> +struct sh_qspi_regs {
> + unsigned char spcr;
> + unsigned char sslp;
> + unsigned char sppcr;
> + unsigned char spsr;
> + unsigned long spdr;
> + unsigned char spscr;
> + unsigned char spssr;
> + unsigned char spbr;
> + unsigned char spdcr;
> + unsigned char spckd;
> + unsigned char sslnd;
> + unsigned char spnd;
> + unsigned char dummy0;
> + unsigned short spcmd0;
> + unsigned short spcmd1;
> + unsigned short spcmd2;
> + unsigned short spcmd3;
> + unsigned char spbfcr;
> + unsigned char dummy1;
> + unsigned short spbdcr;
> + unsigned long spbmul0;
> + unsigned long spbmul1;
> + unsigned long spbmul2;
> + unsigned long spbmul3;
> +};
> +
> +struct sh_qspi_slave {
> + struct spi_slave slave;
> + struct sh_qspi_regs *regs;
> +};
> +
> +static inline struct sh_qspi_slave *to_sh_qspi(struct spi_slave *slave)
> +{
> + return container_of(slave, struct sh_qspi_slave, slave);
> +}
> +
> +static void sh_qspi_init(struct sh_qspi_slave *ss)
> +{
> + /* QSPI initialize */
> + writeb(SPCR_MSTR, &ss->regs->spcr);
> + writeb(0x00, &ss->regs->sslp);
> + writeb(SPPCR_IO3FV|SPPCR_IO2FV, &ss->regs->sppcr);
> +
> + /* Set bit rate. See 58.3.8 Quad Serial Peripheral Interface */
> + writeb(0x01, &ss->regs->spbr);
> +
> + writeb(0x00, &ss->regs->spdcr);
> + writeb(0x00, &ss->regs->spckd);
> + writeb(0x00, &ss->regs->sslnd);
> + writeb(0x00, &ss->regs->spnd);
> + writew(SPCMD_INIT1, &ss->regs->spcmd0);
> + writew(SPCMD_INIT2, &ss->regs->spcmd0);
> + writeb(SPBFCR_TXRST|SPBFCR_RXRST, &ss->regs->spbfcr);
> + writeb(0x00, &ss->regs->spbfcr);
> + writeb(0x00, &ss->regs->spscr);
> + writeb(SPCR_SPE|SPCR_MSTR, &ss->regs->spcr);
> +}
> +
> +static int sh_qspi_xfer(struct sh_qspi_slave *ss, unsigned char *tdata,
> + unsigned char *rdata, unsigned long flags)
> +{
> + while (!(readb(&ss->regs->spsr) & SPSR_SPTEF)) {
> + if (ctrlc())
Looks like you are trying for error check - Just add a print

> + return 1;
> + udelay(10);
> + }
> +
> + writeb(*tdata, (unsigned char *)(&ss->regs->spdr));
> +
> + while ((readw(&ss->regs->spbdcr) != SPBDCR_RXBC0)) {
> + int i = 100;
> +
> + if (ctrlc())
same as above.

> + return 1;
> + while (i--)
> + ;
> + }
> +
> + while (!(readb(&ss->regs->spsr) & SPSR_SPRFF)) {
> + if (ctrlc())
> + return 1;
same as above.

> + udelay(10);
> + }
> +
> + *rdata = readb((unsigned char *)(&ss->regs->spdr));
> +
> + return 0;
> +}
> +
> +int spi_cs_is_valid(unsigned int bus, unsigned int cs)
> +{
> + return 1;
> +}
> +
> +void spi_cs_activate(struct spi_slave *slave)
> +{
> +}
> +
> +void spi_cs_deactivate(struct spi_slave *slave)
> +{
> +}
> +
> +void spi_init(void)
> +{
> + /* nothing to do */
> +}
> +
> +struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
> + unsigned int max_hz, unsigned int mode)
> +{
> + struct sh_qspi_slave *ss;
> +
> + if (!spi_cs_is_valid(bus, cs))
> + return NULL;
> +
> + ss = spi_alloc_slave(struct sh_qspi_slave, bus, cs);
> + if (!ss) {
> + printf("SPI_error: Fail to allocate sh_qspi_slave\n");
> + return NULL;
> + }
> +
> + ss->regs = (struct sh_qspi_regs *)CONFIG_SH_QSPI_BASE;
> +
> + /* Init SH QSPI */
> + sh_qspi_init(ss);
> +
> + return &ss->slave;
> +}
> +
> +void spi_free_slave(struct spi_slave *slave)
> +{
> + struct sh_qspi_slave *spi = to_sh_qspi(slave);
> +
> + free(spi);
> +}
> +
> +int spi_claim_bus(struct spi_slave *slave)
> +{
> + return 0;
> +}
> +
> +void spi_release_bus(struct spi_slave *slave)
> +{
> +}
> +
> +int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
> + void *din, unsigned long flags)
> +{
> + struct sh_qspi_slave *ss = to_sh_qspi(slave);
> + unsigned long nbyte;
> + int ret = 0;
> + unsigned char *tdata, *rdata, dtdata = 0, drdata;
> +
> + if (dout == NULL && din == NULL) {
> + if (flags & SPI_XFER_END)
> + writeb(SPCR_MSTR, &ss->regs->spcr);
> + return 0;
> + }
> +
> + if (bitlen % 8) {
> + printf("%s: bitlen is not 8bit alined %d", __func__, bitlen);
> + return 1;
> + }
> +
> + nbyte = bitlen / 8;
> +

------TAG+
> + if (flags & SPI_XFER_BEGIN) {
> + unsigned long *spbmul0 = &ss->regs->spbmul0;
> + writeb(SPCR_MSTR, &ss->regs->spcr);
> +
> + writew(SPCMD_INIT1, &ss->regs->spcmd0);
> +
> + if (flags & SPI_XFER_END)
> + writel(nbyte, spbmul0);
> + else
> + /* Set 1048576 byte */
> + writel(0x100000, spbmul0);
> +
> + writeb(SPBFCR_TXRST|SPBFCR_RXRST, &ss->regs->spbfcr);
> + writeb(0x00, &ss->regs->spbfcr);
> + writeb(0x00, &ss->regs->spscr);
> + writeb(SPCR_SPE|SPCR_MSTR, &ss->regs->spcr);
> + }
---TAG-

TAG+ .. TAG- code should be part of spi_cs_activate() func..please adjust

> +
> + if (dout != NULL)
> + tdata = (unsigned char *)dout;
> + else
> + tdata = &dtdata;
> +
> + if (din != NULL)
> + rdata = din;
> + else
> + rdata = &drdata;
> +
> + while (nbyte > 0) {

TAG+
> + ret = sh_qspi_xfer(ss, tdata, rdata, flags);
> + if (ret)
> + break;
> + if (dout != NULL)
> + tdata++;
> + if (din != NULL)
> + rdata++;
> + nbyte--;
TAG-

Can you try to write the all code in this function- I think no need to
write extra sh_qspi_xfer()
try to optimize more.. see driver/spi/zynq_spi.c

> + }
> +
> + if (flags & SPI_XFER_END)
> + writeb(SPCR_MSTR, &ss->regs->spcr);

This should be part of spi_cs_deactivate().

--
Thanks,
Jagan.
--------
Jagannadha Sutradharudu Teki,
E: jagannadh.teki at gmail.com, P: +91-9676773388
Engineer - System Software Hacker
U-boot - SPI Custodian and Zynq APSOC
Ln: http://www.linkedin.com/in/jaganteki