[U-Boot] [PATCH v3] nios2: convert nios2 cpu to driver model

Simon Glass sjg at chromium.org
Tue Sep 29 16:08:11 CEST 2015


Hi Thomas,

On 29 September 2015 at 06:15, Thomas Chou <thomas at wytron.com.tw> wrote:
> Convert nios2 cpu to driver model. The cpu parameters are
> extracted from device tree and saved to global data structure.
> We will use them to replace the custom_fpga.h .
>
> Signed-off-by: Thomas Chou <thomas at wytron.com.tw>
> ---
> v2
>   move cpu param setup to arch_cpu_init_dm, remove probe.
> v3
>   fix coding style as Marek suggested.
>   select CMD_CPU.
>
>  arch/Kconfig                         |  3 ++
>  arch/nios2/cpu/cpu.c                 | 75 ++++++++++++++++++++++++++++++++++--
>  arch/nios2/dts/3c120_devboard.dts    |  1 +
>  arch/nios2/include/asm/global_data.h |  8 ++++
>  configs/nios2-generic_defconfig      |  3 +-
>  5 files changed, 85 insertions(+), 5 deletions(-)

Looks good, a few minor comments below.

>
> diff --git a/arch/Kconfig b/arch/Kconfig
> index 207c778..9be1538 100644
> --- a/arch/Kconfig
> +++ b/arch/Kconfig
> @@ -64,6 +64,9 @@ config NIOS2
>         select HAVE_GENERIC_BOARD
>         select SYS_GENERIC_BOARD
>         select SUPPORT_OF_CONTROL
> +       select OF_CONTROL
> +       select DM
> +       select CPU
>
>  config OPENRISC
>         bool "OpenRISC architecture"
> diff --git a/arch/nios2/cpu/cpu.c b/arch/nios2/cpu/cpu.c
> index 39ae972..9e98742 100644
> --- a/arch/nios2/cpu/cpu.c
> +++ b/arch/nios2/cpu/cpu.c
> @@ -6,7 +6,9 @@
>   */
>
>  #include <common.h>
> -#include <asm/nios2.h>
> +#include <cpu.h>
> +#include <dm.h>
> +#include <errno.h>
>  #include <asm/cache.h>
>
>  DECLARE_GLOBAL_DATA_PTR;
> @@ -51,10 +53,77 @@ void dcache_disable(void)
>         flush_dcache(CONFIG_SYS_DCACHE_SIZE, CONFIG_SYS_DCACHELINE_SIZE);
>  }
>
> -int arch_cpu_init(void)
> +int arch_cpu_init_dm(void)
>  {
> -       gd->cpu_clk = CONFIG_SYS_CLK_FREQ;
> +       struct udevice *dev;
> +
> +       uclass_first_device(UCLASS_CPU, &dev);

Should check the error return too.

ret = uclass_first_device(...)
if (ret)
   return ret;

> +       if (!dev)
> +               return -ENODEV;
> +
> +       gd->cpu_clk = fdtdec_get_int(gd->fdt_blob, dev->of_offset,

This code should go in a probe() method in this driver. Then when the
device is probed (by your arch_cpu_init_dm() function this code will
be executed. The problem here is that you are looking at
dev->of_offset, which is the drivers's responsibility. I know this
code is in the same file, but this is not a driver method function.

You could make this briefer by declaring a few locals:

const void *blob = gd->fdt_blob;
int node = dev->of_offset;

> +               "clock-frequency", 0);
> +       gd->arch.dcache_line_size = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
> +               "dcache-line-size", 0);
> +       gd->arch.icache_line_size = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
> +               "icache-line-size", 0);
> +       gd->arch.dcache_size = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
> +               "dcache-size", 0);
> +       gd->arch.icache_size = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
> +               "icache-size", 0);
> +       gd->arch.reset_addr = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
> +               "altr,reset-addr", 0);
> +       gd->arch.exception_addr = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
> +               "altr,exception-addr", 0);
> +       gd->arch.has_mmu = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
> +               "altr,has-mmu", 0);

Should that be fdtdec_get_bool()? Also is there a device tree binding
file for these settings?

> +       gd->arch.io_region_base = gd->arch.has_mmu ? 0xe0000000 : 0x8000000;
>         gd->ram_size = CONFIG_SYS_SDRAM_SIZE;
>
>         return 0;
>  }
> +
> +static int altera_nios2_get_desc(struct udevice *dev, char *buf, int size)
> +{
> +       const char *cpu_name = "Nios-II";
> +
> +       if (size < strlen(cpu_name))
> +               return -ENOSPC;
> +       strcpy(buf, cpu_name);
> +
> +       return 0;
> +}
> +
> +static int altera_nios2_get_info(struct udevice *dev, struct cpu_info *info)
> +{
> +       info->cpu_freq = gd->cpu_clk;
> +       info->features = (1 << CPU_FEAT_L1_CACHE) |
> +               (gd->arch.has_mmu ? (1 << CPU_FEAT_MMU) : 0);
> +
> +       return 0;
> +}
> +
> +static int altera_nios2_get_count(struct udevice *dev)
> +{
> +       return 1;
> +}
> +
> +static const struct cpu_ops altera_nios2_ops = {
> +       .get_desc       = altera_nios2_get_desc,
> +       .get_info       = altera_nios2_get_info,
> +       .get_count      = altera_nios2_get_count,
> +};
> +
> +static const struct udevice_id altera_nios2_ids[] = {
> +       { .compatible = "altr,nios2-1.0" },
> +       { .compatible = "altr,nios2-1.1" },
> +       { }
> +};
> +
> +U_BOOT_DRIVER(altera_nios2) = {
> +       .name           = "altera_nios2",
> +       .id             = UCLASS_CPU,
> +       .of_match       = altera_nios2_ids,
> +       .ops            = &altera_nios2_ops,
> +       .flags          = DM_FLAG_PRE_RELOC,
> +};
> diff --git a/arch/nios2/dts/3c120_devboard.dts b/arch/nios2/dts/3c120_devboard.dts
> index 781a652..2e2956f 100644
> --- a/arch/nios2/dts/3c120_devboard.dts
> +++ b/arch/nios2/dts/3c120_devboard.dts
> @@ -41,6 +41,7 @@
>                         altr,exception-addr = <0xd0000020>;
>                         altr,has-initda = <1>;
>                         altr,has-mmu = <1>;
> +                       u-boot,dm-pre-reloc;
>                 };
>         };
>
> diff --git a/arch/nios2/include/asm/global_data.h b/arch/nios2/include/asm/global_data.h
> index 580b019..ee5180b 100644
> --- a/arch/nios2/include/asm/global_data.h
> +++ b/arch/nios2/include/asm/global_data.h
> @@ -9,6 +9,14 @@
>
>  /* Architecture-specific global data */
>  struct arch_global_data {
> +       u32 dcache_line_size;
> +       u32 icache_line_size;
> +       u32 dcache_size;
> +       u32 icache_size;
> +       u32 reset_addr;
> +       u32 exception_addr;
> +       int has_mmu;
> +       u32 io_region_base;
>  };
>
>  #include <asm-generic/global_data.h>
> diff --git a/configs/nios2-generic_defconfig b/configs/nios2-generic_defconfig
> index ad72272..707ee33 100644
> --- a/configs/nios2-generic_defconfig
> +++ b/configs/nios2-generic_defconfig
> @@ -4,6 +4,7 @@ CONFIG_DM_GPIO=y
>  CONFIG_TARGET_NIOS2_GENERIC=y
>  CONFIG_DEFAULT_DEVICE_TREE="3c120_devboard"
>  CONFIG_HUSH_PARSER=y
> +CONFIG_CMD_CPU=y
>  # CONFIG_CMD_BOOTD is not set
>  # CONFIG_CMD_IMLS is not set
>  # CONFIG_CMD_XIMG is not set
> @@ -13,9 +14,7 @@ CONFIG_HUSH_PARSER=y
>  CONFIG_CMD_DHCP=y
>  # CONFIG_CMD_NFS is not set
>  CONFIG_CMD_PING=y
> -CONFIG_OF_CONTROL=y
>  CONFIG_NET_RANDOM_ETHADDR=y
> -CONFIG_DM=y
>  CONFIG_ALTERA_PIO=y
>  CONFIG_ALTERA_JTAG_UART=y
>  CONFIG_ALTERA_JTAG_UART_BYPASS=y
> --
> 2.1.4
>

Regards,
Simon


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