[U-Boot] [U-Boot, v2, 16/18] clk: rockchip: Add rk322x gamc clock support

[David.Wu]

Hi Philipp,

在 2017/11/26 22:50, Philipp Tomsich 写道:
> 
> On Thu, 9 Nov 2017, David Wu wrote:
> 
>> Assuming mac_clk is fed by an external clock, set clk_rmii_src
>> clock select control register from IO for rgmii interface.
>>
>> Signed-off-by: David Wu <david.wu at rock-chips.com>
>> Acked-by: Philipp Tomsich <philipp.tomsich at theobroma-systems.com>
> 
> Reviewed-by: Philipp Tomsich <philipp.tomsich at theobroma-systems.com>
> 
> See below for requested changes.
> 
>> ---
>>
>> Changes in v2:
>> - New patch
>>
>> drivers/clk/rockchip/clk_rk322x.c | 13 +++++++++++++
>> 1 file changed, 13 insertions(+)
>>
>> diff --git a/drivers/clk/rockchip/clk_rk322x.c 
>> b/drivers/clk/rockchip/clk_rk322x.c
>> index e87267d..5fd27cd 100644
>> --- a/drivers/clk/rockchip/clk_rk322x.c
>> +++ b/drivers/clk/rockchip/clk_rk322x.c
>> @@ -239,6 +239,16 @@ static ulong rockchip_mmc_get_clk(struct 
>> rk322x_cru *cru, uint clk_general_rate,
>>     return DIV_TO_RATE(src_rate, div) / 2;
>> }
>>
>> +static int rk322x_mac_set_clk(struct rk322x_cru *cru,
>> +                  int periph, uint freq)
>> +{
>> +    /* Assuming mac_clk is fed by an external clock */
>> +    rk_clrsetreg(&cru->cru_clksel_con[5], BIT(5),
>> +             BIT(5));
> 
> Please use a symbolic constant for BIT(5).
> 
> If this is the input/output selection for the MAC clk and covered by 
> 'clock_in_out = "input";' in the DTS, then the DTS should be consulted 
> before assuming a specific setting here.
> 

Yes, I think so, but not do it now;
If it is "input", then actually do not need to set clk rate, as long as 
the direction of setting clk, clk rate rely on external clock input may 
originate from PHY.
If it is "output", then also need to set clk rate.

There has been the interface of setting clock rate currently, but not 
set the direction. Can we in the GMAC driver directly set cru registers 
of mac_clk direction through the dts property of "clk_in_out", otherwise 
need clk framework to provide a set of directional interface like 
setting the parent of mac_clk.

>> +
>> +    return 0;
>> +}
>> +
>> static ulong rockchip_mmc_set_clk(struct rk322x_cru *cru, uint 
>> clk_general_rate,
>>                   int periph, uint freq)
>> {
>> @@ -352,6 +362,9 @@ static ulong rk322x_clk_set_rate(struct clk *clk, 
>> ulong rate)
>>     case CLK_DDR:
>>         new_rate = rk322x_ddr_set_clk(priv->cru, rate);
>>         break;
>> +    case SCLK_MAC:
>> +        new_rate = rk322x_mac_set_clk(priv->cru, clk->id, rate);
>> +        break;
>>     default:
>>         return -ENOENT;
>>     }
>>
> 
> 
>