[U-Boot] [PATCH v2] nios2: convert nios2 cpu to driver model

[Marek Vasut <marex@denx.de>]

On Tuesday, September 29, 2015 at 03:28:01 AM, Thomas Chou 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@wytron.com.tw>

Hi!

Minor nitpicks below.

> ---
> v2
>   move cpu param setup to arch_cpu_init_dm, remove probe.
> 
>  arch/Kconfig                         |  3 ++
>  arch/nios2/cpu/cpu.c                 | 76
> ++++++++++++++++++++++++++++++++++-- arch/nios2/dts/3c120_devboard.dts   
> |  1 +
>  arch/nios2/include/asm/global_data.h |  8 ++++
>  configs/nios2-generic_defconfig      |  2 -
>  5 files changed, 85 insertions(+), 5 deletions(-)
> 
> 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

What's this CONFIG_CPU for please ?

>  config OPENRISC
>  	bool "OpenRISC architecture"
> diff --git a/arch/nios2/cpu/cpu.c b/arch/nios2/cpu/cpu.c
> index 39ae972..88984e2 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 +53,78 @@ 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);
> +	if (!dev)
> +		return -ENODEV;
> +
> +	gd->cpu_clk = fdtdec_get_int(gd->fdt_blob, 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);

Shouldn't there be some sort of return value checking here ?

> +	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);

I'd add parenthesis around the bitshifts, for the sake of clarity.
Also, please put the ORR operator@the end of the line.

> +	return 0;
> +}

Thanks a lot :)