[PATCH 1/8] imx8mm: Fix USB reg addresses for i.MX8MM

[Marek Vasut]

On 7/4/21 5:35 PM, Fabio Estevam wrote:
> Hi Marek,

Hi,

> On Sat, Jul 3, 2021 at 10:04 PM Marek Vasut <marex at denx.de> wrote:
> 
>>> Retrieving the USB base addresses from DT would be preferred, yes, but
>>> the current code does not do that.
>>
>> I implemented exactly that in mx6_parse_dt_addrs() , see:
>> 4dcfa3bcbcb ("usb: ehci-mx6: Parse USB PHY and MISC offsets from DT")
> 
> We are talking about USB_BASE_ADDR, right?

All of the addresses used by the driver, I am trying hard to get rid of 
all that hard-coding in the driver. They should be parsed out of DT.

> imx6/imx7/imxrt provide the USB_BASE_ADDR as define.

That's only because they still need to be fully converted, someone needs 
to write the PHY driver for those. For MX8M, the NOP PHY driver is used.

> If we remove the imx6 definition from arch/arm/include/asm/arch-mx6/imx-regs.h
> the ehci-mx6: driver fails to build.
> 
> I didn't want to change ehci-mx6 in this aspect, so that's why I used
> Frieder's patch that passes
> USB_BASE_ADDR via define for i.MX8MM too.
> 
> Is this an acceptable solution?

No, let's not do that, because that exactly un-does the attempt to get 
rid of these hard-coded addresses. Please parse the address out of DT. 
And if you run into something which might still need hard-coded 
addresses, please fix it.

The ehci-mx6 is bad, let's not make it worse, lets fix it instead.

>>> Without providing these defines:
>>>
>>> drivers/usb/host/ehci-mx6.c:254:62: error: ‘USB_BASE_ADDR’ undeclared
>>> (first use in this function); did you mean ‘SRC_BASE_ADDR’?
>>>     254 |  struct usbnc_regs *usbnc = (struct usbnc_regs
>>> *)(uintptr_t)(USB_BASE_ADDR +
>>
>> I suspect you need CONFIG_PHY for mx8m .
> 
> CONFIG_PHY is already selected by imx8mm_evk_defconfig.

USBNC is iMX7 specific , so you cannot hit that error on iMX8M, there is 
#elif defined(CONFIG_MX7) around it.