[U-Boot] [PATCH] FSL PCI: Configure PCIe reference ratio

[York Sun]

On 09/12/2017 10:56 AM, Joakim Tjernlund wrote:
> Most FSL PCIe controllers expects 333 MHz PCI reference clock.
> This clock is derived from the CCB but in many cases the ref.
> clock is not 333 MHz and a divisor needs to be configured.
> 
> This adds PEX_CCB_DIV #define which can be defined for each
> type of CPU/platform.
> 
> Signed-off-by: Joakim Tjernlund <joakim.tjernlund at infinera.com>
> ---
>   drivers/pci/fsl_pci_init.c | 6 ++++++
>   1 file changed, 6 insertions(+)
> 
> diff --git a/drivers/pci/fsl_pci_init.c b/drivers/pci/fsl_pci_init.c
> index 52792dcd59..4d00b3f26c 100644
> --- a/drivers/pci/fsl_pci_init.c
> +++ b/drivers/pci/fsl_pci_init.c
> @@ -322,6 +322,12 @@ void fsl_pci_init(struct pci_controller *hose, struct fsl_pci_info *pci_info)
>   
>   	pci_setup_indirect(hose, cfg_addr, cfg_data);
>   
> +#ifdef PEX_CCB_DIV
> +	/* Configure the PCIE controller core clock ratio */
> +	pci_hose_write_config_dword(hose, dev, 0x440,
> +				    ((gd->bus_clk / 1000000) *
> +				     (16 / PEX_CCB_DIV)) / 333);
> +#endif
>   	block_rev = in_be32(&pci->block_rev1);
>   	if (PEX_IP_BLK_REV_2_2 <= block_rev) {
>   		pi = &pci->pit[2];	/* 0xDC0 */
> 

Mingkai,

Do you ack this change? This presumes the PCIe clock derives from CCB 
bus clock.

York