diff options
| author | Dmitry Baryshkov <dmitry.baryshkov@linaro.org> | 2023-01-13 13:05:37 +0100 |
|---|---|---|
| committer | Bjorn Andersson <andersson@kernel.org> | 2023-01-19 05:50:00 +0100 |
| commit | b3b274bc9d3d7307308aeaf75f70731765ac999a (patch) | |
| tree | 8cc83a96da4ed0b4e114c9c6b1cfda61c53ff49f /drivers/clk | |
| parent | clk: qcom: cpu-8996: skip ACD init if the setup is valid (diff) | |
| download | linux-b3b274bc9d3d7307308aeaf75f70731765ac999a.tar.xz linux-b3b274bc9d3d7307308aeaf75f70731765ac999a.zip | |
clk: qcom: cpu-8996: simplify the cpu_clk_notifier_cb
- Do not use the Alt PLL completely. Switch to smux when necessary to
prevent overvolting
- Restore the parent in case the rate change aborts for some reason
- Do not duplicate resetting the parent in set_parent operation.
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230113120544.59320-8-dmitry.baryshkov@linaro.org
Diffstat (limited to 'drivers/clk')
| -rw-r--r-- | drivers/clk/qcom/clk-cpu-8996.c | 30 |
1 files changed, 19 insertions, 11 deletions
diff --git a/drivers/clk/qcom/clk-cpu-8996.c b/drivers/clk/qcom/clk-cpu-8996.c index 7e5246ca7e7f..cc7ece6a7702 100644 --- a/drivers/clk/qcom/clk-cpu-8996.c +++ b/drivers/clk/qcom/clk-cpu-8996.c @@ -506,27 +506,35 @@ static int cpu_clk_notifier_cb(struct notifier_block *nb, unsigned long event, { struct clk_cpu_8996_pmux *cpuclk = to_clk_cpu_8996_pmux_nb(nb); struct clk_notifier_data *cnd = data; - int ret; switch (event) { case PRE_RATE_CHANGE: - ret = clk_cpu_8996_pmux_set_parent(&cpuclk->clkr.hw, ALT_INDEX); qcom_cpu_clk_msm8996_acd_init(base); + + /* + * Avoid overvolting. clk_core_set_rate_nolock() walks from top + * to bottom, so it will change the rate of the PLL before + * chaging the parent of PMUX. This can result in pmux getting + * clocked twice the expected rate. + * + * Manually switch to PLL/2 here. + */ + if (cnd->new_rate < DIV_2_THRESHOLD && + cnd->old_rate > DIV_2_THRESHOLD) + clk_cpu_8996_pmux_set_parent(&cpuclk->clkr.hw, SMUX_INDEX); + break; - case POST_RATE_CHANGE: - if (cnd->new_rate < DIV_2_THRESHOLD) - ret = clk_cpu_8996_pmux_set_parent(&cpuclk->clkr.hw, - SMUX_INDEX); - else - ret = clk_cpu_8996_pmux_set_parent(&cpuclk->clkr.hw, - ACD_INDEX); + case ABORT_RATE_CHANGE: + /* Revert manual change */ + if (cnd->new_rate < DIV_2_THRESHOLD && + cnd->old_rate > DIV_2_THRESHOLD) + clk_cpu_8996_pmux_set_parent(&cpuclk->clkr.hw, ACD_INDEX); break; default: - ret = 0; break; } - return notifier_from_errno(ret); + return NOTIFY_OK; }; static int qcom_cpu_clk_msm8996_driver_probe(struct platform_device *pdev) |