Alexander Shishkin a écrit :
> Matthieu CASTET <matthieu.castet@xxxxxxxxxx> writes:
>
>> Alexander Shishkin a crit :
>>> + ehci->regs = ci->hw_bank.cap +
>>> + HC_LENGTH(ehci, ehci_readl(ehci, &ehci->caps->hc_capbase));
>>> + ehci->hcs_params = ehci_readl(ehci, &ehci->caps->hcs_params);
>>> + ehci->has_hostpc = 1;
>>> + ehci->sbrn = 0x20;
>> Why do you set has_hostpc = 1 ?
>> This won't work with normal chipidea core ?
>
> ....because this way we get proper mode setting from ehci_reset on
> lpm-capable chipideas, see below.
>
>>> +
>>> + ret = hw_device_reset(ci, USBMODE_CM_HC);
>>> + if (ret)
>>> + goto rm_hcd;
>> Why do you need to do that ? ehci_reset will do it (with tdi_reset).
>
> Actually, it will only do that for non lpm-capable controllers, which
> have USBMODE register in the place where tdi_reset() expects it to
> be. On lpm-capable controllers, USBMODE is in fact where USBMODE_EX
> (from ehci-def.h) points to, so tdi_reset() sort of shoots at nothing in
> particular. Writes to the USBMODE location for such devices are silently
> ignored (maybe we need to tweak tdi_reset() to not do that anyway to be
> no a safe side, but that's another matter).
>
> However, ehci_reset() will still do the right thing if has_hostpc is
> set, so you're right, this reset call is actually not needed.
>
> Having said all that, it seems obvious that has_hostpc setting should
> depend on wheather we are lpm-capable or not. What do you think?
>
If has_hostpc is really chipidea with lpm I think we should :
- rename it to something understandable
- autodetect it like we does in udc (using HCCPARAMS). May be it could be
replaced with ehci_is_TDI(ehci) && HCC_LPM(hcc_params) ?
- fix tdi_reset and tdi_in_host_mode to use the correct register (USBMODE or
USBMODE_EX according to has_hostpc). May be we should move the code [1] in
tdi_reset ?
Is there a public datasheet to lpm chipidea controller ?
Matthieu
[1]
if (ehci->has_hostpc) {
ehci_writel(ehci, USBMODE_EX_HC | USBMODE_EX_VBPS,
(u32 __iomem *)(((u8 *)ehci->regs) + USBMODE_EX));
ehci_writel(ehci, TXFIFO_DEFAULT,
(u32 __iomem *)(((u8 *)ehci->regs) + TXFILLTUNING));
}
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