Re: [PATCH v9 0/8] Add endpoint driver for R-Car PCIe controller

[Lad, Prabhakar]

Hi Pavel,

On Thu, May 7, 2020 at 6:44 PM Pavel Machek <pavel@xxxxxx> wrote:
>
> Hi!
>
>
> > R-Car/RZ-G2x SoC's, this also extends the epf framework to handle multiple windows
> > supported by the controller for mapping PCI address locally.
> >
> > Note:
> > The cadence/rockchip/designware endpoint drivers are build tested only.
> >
> > Changes for v9 (Re-spun this series as there were minimal changes requested):
> ...
> > * Replaced mdelay(1) with usleep_range(1000, 1001) in rcar_pcie_ep_assert_intx()
>
> Are you sure that is good idea? You are requesting 1ms sleep time with 1us tolerance,
> I dont believe common systems can do that.
>
Agreed the systems cannot do that, but the main reason of replacing
mdelay(1) with usleep_range(1000, 1001) was since  pci_epc_raise_irq()
calls mutex_lock() and then this function rcar_pcie_ep_assert_intx(),
so we can assume this function also can sleep. And, according to
Documentation/timers/timers-howto.rst, we should use usleep_range()
instead of mdelay().

Cheers,
--Prabhakar



> Best regards,
>                                                                         Pavel
>
> --
> (english) http://www.livejournal.com/~pavelmachek
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