[U-Boot] [PATCH 4/6] mips: ath79: Add support for ungating USB and ethernet on qca953x

[Marek Vasut]

On 05/31/2016 10:50 AM, Piotr Dymacz wrote:
> Hello,
> 
> 2016-05-31 2:51 GMT+02:00 Marek Vasut <marex at denx.de>:
>> On 05/31/2016 02:35 AM, Wills Wang wrote:
> 
> [snip]
> 
>>>>>   +static int usb_reset_qca953x(void __iomem *reset_regs)
>>>>> +{
>>>>> +    void __iomem *pregs = map_physmem(AR71XX_PLL_BASE, AR71XX_PLL_SIZE,
>>>>> +                      MAP_NOCACHE);
>>>>> +
>>>>> +    clrsetbits_be32(pregs + QCA953X_PLL_SWITCH_CLOCK_CONTROL_REG,
>>>>> +            0xf00, 0x200);
>>
>> Do you know what these magic numbers mean ?
> 
> I can help here.
> 
> This register is common for (almost) all modern QC/A WiSOCs, with
> similar structure, at least for AR934x, QCA953x, QCA955x and QCA956x
> (please take a look at [1]).
> I have seen it (SDK, datasheets) under two different names:
> SWITCH_CLOCK_SPARE and SWITCH_CLOCK_CONTROL, on different addresses
> (offset +/- 1), depending on the SOC.
> 
> The bit field [8:11] is "USB_REFCLK_FREQ_SEL" and it's the same for
> all above SOCs. Value (dec) 2 is for 25 MHz, value 5 for 40 MHz.
> 
> I'm going to provide some patches for ath79 in future, which will make
> code more universal for all QC/A WiSOCs.

Oh, very cool, thanks!

-- 
Best regards,
Marek Vasut