This is a note to let you know that I've just added the patch titled clk: qcom: Allow constant ratio freq tables for rcg to the 4.19-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: clk-qcom-allow-constant-ratio-freq-tables-for-rcg.patch and it can be found in the queue-4.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 906b35355220846461effe62c884d9043892cfb4 Author: Jeffrey Hugo <jeffrey.l.hugo@xxxxxxxxx> Date: Thu Oct 31 11:57:15 2019 -0700 clk: qcom: Allow constant ratio freq tables for rcg [ Upstream commit efd164b5520afd6fb2883b68e0d408a7de29c491 ] Some RCGs (the gfx_3d_src_clk in msm8998 for example) are basically just some constant ratio from the input across the entire frequency range. It would be great if we could specify the frequency table as a single entry constant ratio instead of a long list, ie: { .src = P_GPUPLL0_OUT_EVEN, .pre_div = 3 }, { } So, lets support that. We need to fix a corner case in qcom_find_freq() where if the freq table is non-null, but has no frequencies, we end up returning an "entry" before the table array, which is bad. Then, we need ignore the freq from the table, and instead base everything on the requested freq. Suggested-by: Stephen Boyd <sboyd@xxxxxxxxxx> Signed-off-by: Jeffrey Hugo <jeffrey.l.hugo@xxxxxxxxx> Link: https://lkml.kernel.org/r/20191031185715.15504-1-jeffrey.l.hugo@xxxxxxxxx Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/clk/qcom/clk-rcg2.c b/drivers/clk/qcom/clk-rcg2.c index 52208d4165f4..51b2388d80ac 100644 --- a/drivers/clk/qcom/clk-rcg2.c +++ b/drivers/clk/qcom/clk-rcg2.c @@ -206,6 +206,8 @@ static int _freq_tbl_determine_rate(struct clk_hw *hw, const struct freq_tbl *f, if (clk_flags & CLK_SET_RATE_PARENT) { rate = f->freq; if (f->pre_div) { + if (!rate) + rate = req->rate; rate /= 2; rate *= f->pre_div + 1; } diff --git a/drivers/clk/qcom/common.c b/drivers/clk/qcom/common.c index db9b2471ac40..bfb6d6065a90 100644 --- a/drivers/clk/qcom/common.c +++ b/drivers/clk/qcom/common.c @@ -29,6 +29,9 @@ struct freq_tbl *qcom_find_freq(const struct freq_tbl *f, unsigned long rate) if (!f) return NULL; + if (!f->freq) + return f; + for (; f->freq; f++) if (rate <= f->freq) return f;