[U-Boot] [PATCH] armv8: layerscape platform pcie link up state judgment strongly

[York Sun]

On 08/02/2017 07:58 PM, Bao Xiaowei wrote:
> modifiy the ls_pcie_link_up function, add the following three judging
> mechanisms:
> 
> detect state: return link down status;
> L0 state: return link up status;
> other state: delay about 100ms retrieve Status Returns the corresponding link
> status;

Please pay attention to your upper case and lower case in commit message.

What does the spec say about the timeout? Is 100ms the right time? If 
so, please put a comment in the source code.

> 
> Signed-off-by: Bao Xiaowei <xiaowei.bao at nxp.com>
> ---
>   drivers/pci/pcie_layerscape.c | 17 +++++++++++++----
>   1 file changed, 13 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/pci/pcie_layerscape.c b/drivers/pci/pcie_layerscape.c
> index 7565e2f..4446ac9 100644
> --- a/drivers/pci/pcie_layerscape.c
> +++ b/drivers/pci/pcie_layerscape.c
> @@ -65,13 +65,22 @@ static int ls_pcie_ltssm(struct ls_pcie *pcie)
>   
>   static int ls_pcie_link_up(struct ls_pcie *pcie)
>   {
> -	int ltssm;
> +	int ltssm, i;
>   
>   	ltssm = ls_pcie_ltssm(pcie);
> -	if (ltssm < LTSSM_PCIE_L0)
> +	if ((ltssm == 0) || (ltssm == 1))
>   		return 0;
> -
> -	return 1;
> +	else if (ltssm == LTSSM_PCIE_L0)
> +		return 1;
> +	else {
> +		for (i = 0; i < 100; i++) {
> +			udelay(1000);
> +			ltssm = ls_pcie_ltssm(pcie);
> +			if (ltssm == LTSSM_PCIE_L0)
> +				return 1;
> +		}
> +		return 0;
> +	}

A comment to summary the logic would be nice.

York