[U-Boot] [PATCH 4/8] sunxi: add bank detection code to H3 DRAM initialization code

[André Przywara]

On 11/03/17 16:19, Icenowy Zheng wrote:
> Some DDR2 DRAM have only four banks, not eight.
> 
> Add code to detect this situation.
> 
> Signed-off-by: Icenowy Zheng <icenowy at aosc.xyz>

Reviewed-by: Andre Przywara <andre.przywara at arm.com>

Thanks,
Andre.

> ---
>  arch/arm/mach-sunxi/dram_sunxi_dw.c | 19 +++++++++++++++----
>  1 file changed, 15 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/arm/mach-sunxi/dram_sunxi_dw.c b/arch/arm/mach-sunxi/dram_sunxi_dw.c
> index b08998c0d1..bb4457d2b8 100644
> --- a/arch/arm/mach-sunxi/dram_sunxi_dw.c
> +++ b/arch/arm/mach-sunxi/dram_sunxi_dw.c
> @@ -31,6 +31,7 @@ struct dram_para {
>  	u8 bus_full_width;
>  	u8 dual_rank;
>  	u8 row_bits;
> +	u8 bank_bits;
>  	const u8 dx_read_delays[NR_OF_BYTE_LANES][LINES_PER_BYTE_LANE];
>  	const u8 dx_write_delays[NR_OF_BYTE_LANES][LINES_PER_BYTE_LANE];
>  	const u8 ac_delays[31];
> @@ -367,7 +368,7 @@ static void mctl_set_cr(struct dram_para *para)
>  			(struct sunxi_mctl_com_reg *)SUNXI_DRAM_COM_BASE;
>  
>  	writel(MCTL_CR_BL8 | MCTL_CR_2T | MCTL_CR_DDR3 | MCTL_CR_INTERLEAVED |
> -	       MCTL_CR_EIGHT_BANKS |
> +	       (para->bank_bits == 3 ? MCTL_CR_EIGHT_BANKS : MCTL_CR_FOUR_BANKS) |
>  	       MCTL_CR_BUS_FULL_WIDTH(para->bus_full_width) |
>  	       (para->dual_rank ? MCTL_CR_DUAL_RANK : MCTL_CR_SINGLE_RANK) |
>  	       MCTL_CR_PAGE_SIZE(para->page_size) |
> @@ -575,10 +576,19 @@ static void mctl_auto_detect_dram_size(struct dram_para *para)
>  	/* detect row address bits */
>  	para->page_size = 512;
>  	para->row_bits = 16;
> +	para->bank_bits = 2;
>  	mctl_set_cr(para);
>  
>  	for (para->row_bits = 11; para->row_bits < 16; para->row_bits++)
> -		if (mctl_mem_matches((1 << (para->row_bits + 3)) * para->page_size))
> +		if (mctl_mem_matches((1 << (para->row_bits + para->bank_bits)) * para->page_size))
> +			break;
> +
> +	/* detect bank address bits */
> +	para->bank_bits = 3;
> +	mctl_set_cr(para);
> +
> +	for (para->bank_bits = 2; para->bank_bits < 3; para->bank_bits++)
> +		if (mctl_mem_matches((1 << para->bank_bits) * para->page_size))
>  			break;
>  
>  	/* detect page size */
> @@ -640,6 +650,7 @@ unsigned long sunxi_dram_init(void)
>  		.dual_rank = 0,
>  		.bus_full_width = 1,
>  		.row_bits = 15,
> +		.bank_bits = 3,
>  		.page_size = 4096,
>  
>  #if defined(CONFIG_MACH_SUN8I_H3)
> @@ -689,6 +700,6 @@ unsigned long sunxi_dram_init(void)
>  	mctl_auto_detect_dram_size(&para);
>  	mctl_set_cr(&para);
>  
> -	return (1UL << (para.row_bits + 3)) * para.page_size *
> -						(para.dual_rank ? 2 : 1);
> +	return (1UL << (para.row_bits + para.bank_bits)) * para.page_size *
> +	       (para.dual_rank ? 2 : 1);
>  }
>