[U-Boot] [PATCH] kirkwood: implement kw_sdram_bs_set()

[Albert ARIBAUD <albert.u.boot@aribaud.net>]

Hi Gerlando,

On Fri, 29 Jun 2012 13:37:54 +0200, Gerlando Falauto
<gerlando.falauto@keymile.com> wrote:
> Some boards might be equipped with different SDRAM configurations.
> When that is the case, CPU CS Window Size Register (CS[0]n Size)
> should be set to the biggest value through board.cfg file; then its
> value can be fixed at runtime according to the detected SDRAM size.
> 
> Therefore, implement kw_sdram_bs_set(), to be called for instance
> within board_early_init_f().
> 
> Signed-off-by: Gerlando Falauto <gerlando.falauto@keymile.com>
> Cc: Marek Vasut <marex@denx.de>
> Cc: Prafulla Wadaskar <prafulla@marvell.com>
> Cc: Wolfgang Denk <wd@denx.de>
> Cc: Valentin Longchamp <valentin.longchamp@keymile.com>
> Cc: Holger Brunck <holger.brunck@keymile.com>
> ---
>  arch/arm/cpu/arm926ejs/kirkwood/dram.c   |   28
> ++++++++++++++++++++++++++-- arch/arm/include/asm/arch-kirkwood/cpu.h
> |    2 ++ 2 files changed, 28 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm/cpu/arm926ejs/kirkwood/dram.c
> b/arch/arm/cpu/arm926ejs/kirkwood/dram.c index 2441554..e5409f1 100644
> --- a/arch/arm/cpu/arm926ejs/kirkwood/dram.c
> +++ b/arch/arm/cpu/arm926ejs/kirkwood/dram.c
> @@ -28,8 +28,15 @@
>  
>  DECLARE_GLOBAL_DATA_PTR;
>  
> -#define KW_REG_CPUCS_WIN_BAR(x)		(KW_REGISTER(0x1500)
> + (x * 0x08)) -#define KW_REG_CPUCS_WIN_SZ(x)
> (KW_REGISTER(0x1504) + (x * 0x08)) +/* Kirkwood memory registers */
> +#define KW_REG_CPUCS_WIN_BAR(x)		(KW_REGISTER(0x1500)
> + ((x) * 0x08)) +#define KW_REG_CPUCS_WIN_SZ(x)
> (KW_REGISTER(0x1504) + ((x) * 0x08)) +
> +#define KW_REG_CPUCS_WIN_ENABLE		(1 << 0)
> +#define KW_REG_CPUCS_WIN_WR_PROTECT	(1 << 1)
> +#define KW_REG_CPUCS_WIN_WIN0_CS(x)	(((x) & 0x3) << 2)
> +#define KW_REG_CPUCS_WIN_SIZE(x)	(((x) & 0xff) << 24)
> +
>  /*
>   * kw_sdram_bar - reads SDRAM Base Address Register
>   */
> @@ -60,6 +67,23 @@ u32 kw_sdram_bs(enum memory_bank bank)
>  	return result;
>  }
>  
> +/*
> + * kw_sdram_bs_set - writes SDRAM Bank size
> + */
> +void kw_sdram_bs_set(enum memory_bank bank, u32 size)
> +{
> +	/* Read current register value */
> +	u32 reg = readl(KW_REG_CPUCS_WIN_SZ(bank));
> +
> +	/* Clear window size */
> +	reg &= ~KW_REG_CPUCS_WIN_SIZE(0xFF);
> +
> +	/* Set new window size */
> +	reg |= KW_REG_CPUCS_WIN_SIZE((size - 1) >> 24);
> +
> +	writel(reg, KW_REG_CPUCS_WIN_SZ(bank));
> +}
> +
>  #ifndef CONFIG_SYS_BOARD_DRAM_INIT
>  int dram_init(void)
>  {
> diff --git a/arch/arm/include/asm/arch-kirkwood/cpu.h
> b/arch/arm/include/asm/arch-kirkwood/cpu.h index d28c51a..807154e
> 100644 --- a/arch/arm/include/asm/arch-kirkwood/cpu.h
> +++ b/arch/arm/include/asm/arch-kirkwood/cpu.h
> @@ -159,6 +159,8 @@ void reset_cpu(unsigned long ignored);
>  unsigned char get_random_hex(void);
>  unsigned int kw_sdram_bar(enum memory_bank bank);
>  unsigned int kw_sdram_bs(enum memory_bank bank);
> +void kw_sdram_bs_set(enum memory_bank bank, u32 size);
> +
>  int kw_config_adr_windows(void);
>  void kw_config_gpio(unsigned int gpp0_oe_val, unsigned int
> gpp1_oe_val, unsigned int gpp0_oe, unsigned int gpp1_oe);

I don't like isolated patches that seem to create dead code. I know
here it is not the goal, of course; so why not submit a two-patch
series, providing both the new code *and* a use for it?

Amicalement,
-- 
Albert.