[U-Boot] [PATCH v2] mmc/dwmmc: modify FIFO threshold only if value explicitly set

[Jaehoon Chung <jh80.chung@samsung.com>]

Acked-by: Jaehoon Chung <jh80.chung@samsung.com>

On 11/27/2013 10:00 PM, Alexey Brodkin wrote:
> If platform provides "host->fifoth_val" it will be used for
> initialization of DWMCI_FIFOTH register. Otherwise default value will be
> used.
> 
> This implementation allows:
>  * escape unclear and recursive calculations that are currently in use
>  * use whatever custom value for DWMCI_FIFOTH initialization if any
> particular SoC requires it
> 
> Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
> 
> Cc: Mischa Jonker <mjonker@synopsys.com>
> Cc: Alim Akhtar <alim.akhtar@samsung.com>
> Cc: Rajeshwari Shinde <rajeshwari.s@samsung.com>
> Cc: Jaehoon Chung <jh80.chung@samsung.com>
> Cc: Amar <amarendra.xt@samsung.com>
> Cc: Kyungmin Park <kyungmin.park@samsung.com>
> Cc: Minkyu Kang <mk7.kang@samsung.com>
> Cc: Simon Glass <sjg@chromium.org>
> Cc: Pantelis Antoniou <panto@antoniou-consulting.com>
> Cc: Andy Fleming <afleming@freescale.com>
> ---
>  drivers/mmc/dw_mmc.c | 9 ++-------
>  1 file changed, 2 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/mmc/dw_mmc.c b/drivers/mmc/dw_mmc.c
> index 1e0f72b..a47e02c 100644
> --- a/drivers/mmc/dw_mmc.c
> +++ b/drivers/mmc/dw_mmc.c
> @@ -300,7 +300,6 @@ static void dwmci_set_ios(struct mmc *mmc)
>  static int dwmci_init(struct mmc *mmc)
>  {
>  	struct dwmci_host *host = (struct dwmci_host *)mmc->priv;
> -	u32 fifo_size;
>  
>  	if (host->quirks & DWMCI_QUIRK_DISABLE_SMU) {
>  		dwmci_writel(host, EMMCP_MPSBEGIN0, 0);
> @@ -330,13 +329,9 @@ static int dwmci_init(struct mmc *mmc)
>  	dwmci_writel(host, DWMCI_IDINTEN, 0);
>  	dwmci_writel(host, DWMCI_BMOD, 1);
>  
> -	if (!host->fifoth_val) {
> -		fifo_size = dwmci_readl(host, DWMCI_FIFOTH);
> -		fifo_size = ((fifo_size & RX_WMARK_MASK) >> RX_WMARK_SHIFT) + 1;
> -		host->fifoth_val = MSIZE(0x2) | RX_WMARK(fifo_size / 2 - 1) |
> -			TX_WMARK(fifo_size / 2);
> +	if (host->fifoth_val) {
> +		dwmci_writel(host, DWMCI_FIFOTH, host->fifoth_val);
>  	}
> -	dwmci_writel(host, DWMCI_FIFOTH, host->fifoth_val);
>  
>  	dwmci_writel(host, DWMCI_CLKENA, 0);
>  	dwmci_writel(host, DWMCI_CLKSRC, 0);
>