[U-Boot] [PATCH] serial-arc: switch to DM

Simon Glass sjg at chromium.org
Sat Apr 4 01:15:08 CEST 2015


Hi Alexey,

On 31 March 2015 at 04:18, Alexey Brodkin <Alexey.Brodkin at synopsys.com> wrote:
>
> Now when all infrastructure in ARC is ready for it let's switch ARC UART
> to driver model.
>
> Signed-off-by: Alexey Brodkin <abrodkin at synopsys.com>
> Cc: Masahiro Yamada <yamada.masahiro at socionext.com>
> Cc: Simon Glass <sjg at chromium.org>
> ---
>  arch/Kconfig                   |   1 +
>  arch/arc/dts/Makefile          |  11 +++++
>  arch/arc/dts/arcangel4.dts     |  24 ++++++++++
>  arch/arc/dts/skeleton.dtsi     |  13 ++++++
>  configs/arcangel4-be_defconfig |   5 ++
>  configs/arcangel4_defconfig    |   5 ++
>  drivers/serial/serial_arc.c    | 102 ++++++++++++++++++++++++++++-------------
>  7 files changed, 129 insertions(+), 32 deletions(-)
>  create mode 100644 arch/arc/dts/Makefile
>  create mode 100644 arch/arc/dts/arcangel4.dts
>  create mode 100644 arch/arc/dts/skeleton.dtsi
>
> diff --git a/arch/Kconfig b/arch/Kconfig
> index ca617e7..2ca5305 100644
> --- a/arch/Kconfig
> +++ b/arch/Kconfig
> @@ -14,6 +14,7 @@ config ARC
>         select HAVE_PRIVATE_LIBGCC
>         select HAVE_GENERIC_BOARD
>         select SYS_GENERIC_BOARD
> +       select SUPPORT_OF_CONTROL
>
>  config ARM
>         bool "ARM architecture"
> diff --git a/arch/arc/dts/Makefile b/arch/arc/dts/Makefile
> new file mode 100644
> index 0000000..a155311
> --- /dev/null
> +++ b/arch/arc/dts/Makefile
> @@ -0,0 +1,11 @@
> +dtb-$(CONFIG_TARGET_ARCANGEL4) +=  arcangel4.dtb
> +
> +targets += $(dtb-y)
> +
> +DTC_FLAGS += -R 4 -p 0x1000
> +
> +PHONY += dtbs
> +dtbs: $(addprefix $(obj)/, $(dtb-y))
> +       @:
> +
> +clean-files := *.dtb
> diff --git a/arch/arc/dts/arcangel4.dts b/arch/arc/dts/arcangel4.dts
> new file mode 100644
> index 0000000..bfcb9d8
> --- /dev/null
> +++ b/arch/arc/dts/arcangel4.dts
> @@ -0,0 +1,24 @@
> +/*
> + * Copyright (C) 2015 Synopsys, Inc. (www.synopsys.com)
> + *
> + * SPDX-License-Identifier:    GPL-2.0+
> + */
> +/dts-v1/;
> +
> +#include "skeleton.dtsi"
> +
> +/ {
> +       #address-cells = <1>;
> +       #size-cells = <1>;
> +
> +       aliases {
> +               console = &arcuart0;
> +       };
> +
> +       arcuart0: serial at 0xc0fc1000 {
> +               compatible = "snps,arc-uart";
> +               reg = <0xc0fc1000 0x100>;
> +               clock-frequency = <80000000>;
> +       };
> +
> +};
> diff --git a/arch/arc/dts/skeleton.dtsi b/arch/arc/dts/skeleton.dtsi
> new file mode 100644
> index 0000000..b41d241
> --- /dev/null
> +++ b/arch/arc/dts/skeleton.dtsi
> @@ -0,0 +1,13 @@
> +/*
> + * Skeleton device tree; the bare minimum needed to boot; just include and
> + * add a compatible value.  The bootloader will typically populate the memory
> + * node.
> + */
> +
> +/ {
> +       #address-cells = <1>;
> +       #size-cells = <1>;
> +       chosen { };
> +       aliases { };
> +       memory { device_type = "memory"; reg = <0 0>; };
> +};
> diff --git a/configs/arcangel4-be_defconfig b/configs/arcangel4-be_defconfig
> index 990c74a..36ea6be 100644
> --- a/configs/arcangel4-be_defconfig
> +++ b/configs/arcangel4-be_defconfig
> @@ -1,5 +1,10 @@
>  CONFIG_ARC=y
>  CONFIG_CPU_BIG_ENDIAN=y
>  CONFIG_TARGET_ARCANGEL4=y
> +CONFIG_DM=y
> +CONFIG_DM_SERIAL=y
> +CONFIG_DEFAULT_DEVICE_TREE="arcangel4"
>  CONFIG_SYS_TEXT_BASE=0x81000000
>  CONFIG_SYS_CLK_FREQ=70000000
> +CONFIG_OF_CONTROL=y
> +CONFIG_OF_EMBED=y
> diff --git a/configs/arcangel4_defconfig b/configs/arcangel4_defconfig
> index fbc0ffe..75a91c8 100644
> --- a/configs/arcangel4_defconfig
> +++ b/configs/arcangel4_defconfig
> @@ -1,4 +1,9 @@
>  CONFIG_ARC=y
>  CONFIG_TARGET_ARCANGEL4=y
> +CONFIG_DM=y
> +CONFIG_DM_SERIAL=y
> +CONFIG_DEFAULT_DEVICE_TREE="arcangel4"
>  CONFIG_SYS_TEXT_BASE=0x81000000
>  CONFIG_SYS_CLK_FREQ=70000000
> +CONFIG_OF_CONTROL=y
> +CONFIG_OF_EMBED=y
> diff --git a/drivers/serial/serial_arc.c b/drivers/serial/serial_arc.c
> index 0ee8ce5..54e596c 100644
> --- a/drivers/serial/serial_arc.c
> +++ b/drivers/serial/serial_arc.c
> @@ -8,6 +8,7 @@
>   */
>
>  #include <common.h>
> +#include <dm.h>
>  #include <serial.h>
>
>  DECLARE_GLOBAL_DATA_PTR;
> @@ -23,21 +24,23 @@ struct arc_serial_regs {
>         unsigned int baudh;
>  };
>
> +
> +struct arc_serial_platdata {
> +       struct arc_serial_regs *reg;
> +       unsigned int uartclk;
> +};
> +
>  /* Bit definitions of STATUS register */
>  #define UART_RXEMPTY           (1 << 5)
>  #define UART_OVERFLOW_ERR      (1 << 1)
>  #define UART_TXEMPTY           (1 << 7)
>
> -struct arc_serial_regs *regs = (struct arc_serial_regs *)CONFIG_ARC_UART_BASE;
> -
> -static void arc_serial_setbrg(void)
> +static int arc_serial_setbrg(struct udevice *dev, int baudrate)
>  {
> -       int arc_console_baud;
> +       struct arc_serial_platdata *plat = dev->platdata;
> +       struct arc_serial_regs *const regs = plat->reg;
> +       int arc_console_baud = gd->cpu_clk / (baudrate * 4) - 1;
>
> -       if (!gd->baudrate)
> -               gd->baudrate = CONFIG_BAUDRATE;
> -
> -       arc_console_baud = gd->cpu_clk / (gd->baudrate * 4) - 1;
>         writeb(arc_console_baud & 0xff, &regs->baudl);
>
>  #ifdef CONFIG_ARC
> @@ -56,33 +59,49 @@ static void arc_serial_setbrg(void)
>  #else
>         writeb((arc_console_baud & 0xff00) >> 8, &regs->baudh);
>  #endif
> -}
>
> -static int arc_serial_init(void)
> -{
> -       serial_setbrg();
>         return 0;
>  }
>
> -static void arc_serial_putc(const char c)
> +static int arc_serial_putc(struct udevice *dev, const char c)
>  {
> +       struct arc_serial_platdata *plat = dev->platdata;
> +       struct arc_serial_regs *const regs = plat->reg;
> +
>         if (c == '\n')
> -               arc_serial_putc('\r');
> +               arc_serial_putc(dev, '\r');

In the driver model case this is done in the uclass.
>
>         while (!(readb(&regs->status) & UART_TXEMPTY))
>                 ;
>
>         writeb(c, &regs->data);
> +
> +       return 0;
>  }
>
> -static int arc_serial_tstc(void)
> +static int arc_serial_tstc(struct arc_serial_regs *const regs)
>  {
>         return !(readb(&regs->status) & UART_RXEMPTY);
>  }
>
> -static int arc_serial_getc(void)
> +static int arc_serial_pending(struct udevice *dev, bool input)
> +{
> +       struct arc_serial_platdata *plat = dev->platdata;
> +       struct arc_serial_regs *const regs = plat->reg;
> +       uint32_t status = readb(&regs->status);
> +
> +       if (input)
> +               return status & UART_RXEMPTY ? 0 : 1;
> +       else
> +               return status & UART_TXEMPTY ? 0 : 1;
> +}
> +
> +static int arc_serial_getc(struct udevice *dev)
>  {
> -       while (!arc_serial_tstc())
> +       struct arc_serial_platdata *plat = dev->platdata;
> +       struct arc_serial_regs *const regs = plat->reg;
> +
> +       while (!arc_serial_tstc(regs))
>                 ;

This should return -EAGAIN and should not have a loop here.

>
>         /* Check for overflow errors */
> @@ -92,23 +111,42 @@ static int arc_serial_getc(void)
>         return readb(&regs->data) & 0xFF;
>  }
>
> -static struct serial_device arc_serial_drv = {
> -       .name   = "arc_serial",
> -       .start  = arc_serial_init,
> -       .stop   = NULL,
> -       .setbrg = arc_serial_setbrg,
> -       .putc   = arc_serial_putc,
> -       .puts   = default_serial_puts,
> -       .getc   = arc_serial_getc,
> -       .tstc   = arc_serial_tstc,
> -};
> -
> -void arc_serial_initialize(void)
> +static int arc_serial_probe(struct udevice *dev)
>  {
> -       serial_register(&arc_serial_drv);
> +       return 0;
>  }
>
> -__weak struct serial_device *default_serial_console(void)
> +static const struct dm_serial_ops arc_serial_ops = {
> +       .putc = arc_serial_putc,
> +       .pending = arc_serial_pending,
> +       .getc = arc_serial_getc,
> +       .setbrg = arc_serial_setbrg,
> +};
> +
> +static const struct udevice_id arc_serial_ids[] = {
> +       { .compatible = "snps,arc-uart" },
> +       { }
> +};
> +
> +static int arc_serial_ofdata_to_platdata(struct udevice *dev)
>  {
> -       return &arc_serial_drv;
> +       struct arc_serial_platdata *plat = dev_get_platdata(dev);
> +       DECLARE_GLOBAL_DATA_PTR;
> +
> +       plat->reg = (struct arc_serial_regs *)fdtdec_get_addr(gd->fdt_blob,
> +                                                       dev->of_offset, "reg");
> +       plat->uartclk = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
> +                                      "clock-frequency", 0);
> +
> +       return 0;
>  }
> +
> +U_BOOT_DRIVER(serial_arc) = {
> +       .name   = "serial_arc",
> +       .id     = UCLASS_SERIAL,
> +       .of_match = arc_serial_ids,
> +       .ofdata_to_platdata = arc_serial_ofdata_to_platdata,
> +       .probe = arc_serial_probe,
> +       .ops    = &arc_serial_ops,
> +       .flags = DM_FLAG_PRE_RELOC,
> +};
> --
> 2.1.0
>

Regards,
Simon


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