lkml.org 
[lkml]   [2024]   [Jan]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v5 5/5] PCI: qcom: Add OPP support to scale performance state of power domain
On 08-01-24, 18:49, Krishna Chaitanya Chundru wrote:
> We calculate ICC BW voting based up on PCIe speed and PCIe width.
>
> Right now we are adding the opp table based up on PCIe speed.
>
> Each PCIe controller can support multiple lane configurations like x1, x2,
> x4, x8, x16 based up on controller capability.
>
> So for each GEN speed we need  up to 5 entries in OPP table. This will make
> OPP table very long.
>
> It is best to calculate the ICC BW voting in the driver itself and apply
> them through ICC driver.

I see. Are the lane configurations fixed for a platform ? I mean, do you change
those configurations at runtime or is that something that never changes, but the
driver can end up getting used on a hardware that supports any one of them ?

If they are fixed (second case), then you can use dev_pm_opp_set_prop_name() to
make that easier for you. With that you will only need 5 OPP entries, but each
of them will have five values of bw:

bw-x1, bw-x2, .... and you can select one of them during initialization.

--
viresh

\
 
 \ /
  Last update: 2024-01-10 12:51    [W:0.060 / U:0.736 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site