ipq40xx: fix apss cpu overclocking spam
authorChristian Lamparter <chunkeey@gmail.com>
Sun, 11 Mar 2018 15:42:29 +0000 (16:42 +0100)
committerMathias Kresin <dev@kresin.me>
Wed, 14 Mar 2018 18:04:51 +0000 (19:04 +0100)
commita44d435c1dc14ffdfb9b533b32eecd23178af151
tree5846e33ae169c379fdb24d7a5a7272022bcae010
parent1b906723ebea2319ba428ae708867273805ddd43
ipq40xx: fix apss cpu overclocking spam

There's an interaction issue between the clk changes:"
clk: qcom: ipq4019: Add the apss cpu pll divider clock node
clk: qcom: ipq4019: remove fixed clocks and add pll clocks
" and the cpufreq-dt.

cpufreq-dt is now spamming the kernel-log with the following:

[ 1099.190658] cpu cpu0: dev_pm_opp_set_rate: failed to find current OPP
for freq 761142857 (-34)

This only happens on certain devices like the Compex WPJ428
and AVM FritzBox!4040. However, other devices like the Asus
RT-AC58U and Meraki MR33 work just fine.

The issue stem from the fact that all higher CPU-Clocks
are achieved by switching the clock-parent to the P_DDRPLLAPSS
(ddrpllapss). Which is set by Qualcomm's proprietary bootcode
as part of the DDR calibration.

For example, the FB4040 uses 256 MiB Nanya NT5CC128M16IP clocked
at round 533 MHz (ddrpllsdcc = 190285714 Hz).

whereas the 128 MiB Nanya NT5CC64M16GP-DI in the ASUS RT-AC58U is
clocked at a slightly higher 537 MHz ( ddrpllsdcc = 192000000 Hz).

Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
target/linux/ipq40xx/patches-4.14/017-qcom-ipq4019-add-cpu-operating-points-for-cpufreq-su.patch
target/linux/ipq40xx/patches-4.14/900-clk-fix.patch [new file with mode: 0644]