Hi Marek,
On Mon, Mar 19, 2018 at 10:53 AM, Marek Vasut <marek.vasut@xxxxxxxxx> wrote:
> On 03/19/2018 09:38 AM, Simon Horman wrote:
>> On Sun, Mar 18, 2018 at 11:52:52AM +0100, Marek Vasut wrote:
>>> The data link active signal usually takes ~20 uSec to be asserted,
>>> poll the bit more often to avoid useless delays in this function.
>>>
>>> Signed-off-by: Marek Vasut <marek.vasut+renesas@xxxxxxxxx>
>>> Cc: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
>>> Cc: Phil Edworthy <phil.edworthy@xxxxxxxxxxx>
>>> Cc: Simon Horman <horms+renesas@xxxxxxxxxxxx>
>>> Cc: Wolfram Sang <wsa@xxxxxxxxxxxxx>
>>> Cc: linux-renesas-soc@xxxxxxxxxxxxxxx
>>
>> Unless my eyes deceive me this seems to be quite a lot (100x) more often,
>> but so be it.
>
> It's just a higher frequency to avoid slowdown when bringing the link up.
No it isn't: you replaced a sleep by a delay, thus making it blocking.
So this can spin for up to 50 ms (+ overhead)?
>>> --- a/drivers/pci/host/pcie-rcar.c
>>> +++ b/drivers/pci/host/pcie-rcar.c
>>> @@ -528,13 +528,13 @@ static void phy_write_reg(struct rcar_pcie *pcie,
>>>
>>> static int rcar_pcie_wait_for_dl(struct rcar_pcie *pcie)
>>> {
>>> - unsigned int timeout = 10;
>>> + unsigned int timeout = 10000;
>>>
>>> while (timeout--) {
>>> if ((rcar_pci_read_reg(pcie, PCIETSTR) & DATA_LINK_ACTIVE))
>>> return 0;
>>>
>>> - msleep(5);
>>> + udelay(5);
>>> }
>>>
>>> return -ETIMEDOUT;
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
