From: Martin Blumenstingl <martin.blumenstingl@googlemail.com> To: linux-clk@vger.kernel.org, sboyd@kernel.org Cc: linux-arm-kernel@lists.infradead.org, knaerzche@gmail.com, mturquette@baylibre.com, Martin Blumenstingl <martin.blumenstingl@googlemail.com> Subject: [PATCH clk-fixes v1 1/2] clk: composite: Also consider .determine_rate for rate + mux composites Date: Sat, 16 Oct 2021 12:50:21 +0200 [thread overview] Message-ID: <20211016105022.303413-2-martin.blumenstingl@googlemail.com> (raw) In-Reply-To: <20211016105022.303413-1-martin.blumenstingl@googlemail.com> Commit 69a00fb3d69706 ("clk: divider: Implement and wire up .determine_rate by default") switches clk_divider_ops to implement .determine_rate by default. This breaks composite clocks with multiple parents because clk-composite.c does not use the special handling for mux + divider combinations anymore (that was restricted to rate clocks which only implement .round_rate, but not .determine_rate). Alex reports: This breaks lot of clocks for Rockchip which intensively uses composites, i.e. those clocks will always stay at the initial parent, which in some cases is the XTAL clock and I strongly guess it is the same for other platforms, which use composite clocks having more than one parent (e.g. mediatek, ti ...) Example (RK3399) clk_sdio is set (initialized) with XTAL (24 MHz) as parent in u-boot. It will always stay at this parent, even if the mmc driver sets a rate of 200 MHz (fails, as the nature of things), which should switch it to any of its possible parent PLLs defined in mux_pll_src_cpll_gpll_npll_ppll_upll_24m_p (see clk-rk3399.c) - which never happens. Restore the original behavior by changing the priority of the conditions inside clk-composite.c. Now the special rate + mux case (with rate_ops having a .round_rate - which is still the case for the default clk_divider_ops) is preferred over rate_ops which have .determine_rate defined (and not further considering the mux). Fixes: 69a00fb3d69706 ("clk: divider: Implement and wire up .determine_rate by default") Reported-by: Alex Bee <knaerzche@gmail.com> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> --- drivers/clk/clk-composite.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/clk/clk-composite.c b/drivers/clk/clk-composite.c index c7b97fb0051b..ba8d4d8cf8dd 100644 --- a/drivers/clk/clk-composite.c +++ b/drivers/clk/clk-composite.c @@ -58,11 +58,8 @@ static int clk_composite_determine_rate(struct clk_hw *hw, long rate; int i; - if (rate_hw && rate_ops && rate_ops->determine_rate) { - __clk_hw_set_clk(rate_hw, hw); - return rate_ops->determine_rate(rate_hw, req); - } else if (rate_hw && rate_ops && rate_ops->round_rate && - mux_hw && mux_ops && mux_ops->set_parent) { + if (rate_hw && rate_ops && rate_ops->round_rate && + mux_hw && mux_ops && mux_ops->set_parent) { req->best_parent_hw = NULL; if (clk_hw_get_flags(hw) & CLK_SET_RATE_NO_REPARENT) { @@ -107,6 +104,9 @@ static int clk_composite_determine_rate(struct clk_hw *hw, req->rate = best_rate; return 0; + } else if (rate_hw && rate_ops && rate_ops->determine_rate) { + __clk_hw_set_clk(rate_hw, hw); + return rate_ops->determine_rate(rate_hw, req); } else if (mux_hw && mux_ops && mux_ops->determine_rate) { __clk_hw_set_clk(mux_hw, hw); return mux_ops->determine_rate(mux_hw, req); -- 2.33.1
WARNING: multiple messages have this Message-ID (diff)
From: Martin Blumenstingl <martin.blumenstingl@googlemail.com> To: linux-clk@vger.kernel.org, sboyd@kernel.org Cc: linux-arm-kernel@lists.infradead.org, knaerzche@gmail.com, mturquette@baylibre.com, Martin Blumenstingl <martin.blumenstingl@googlemail.com> Subject: [PATCH clk-fixes v1 1/2] clk: composite: Also consider .determine_rate for rate + mux composites Date: Sat, 16 Oct 2021 12:50:21 +0200 [thread overview] Message-ID: <20211016105022.303413-2-martin.blumenstingl@googlemail.com> (raw) In-Reply-To: <20211016105022.303413-1-martin.blumenstingl@googlemail.com> Commit 69a00fb3d69706 ("clk: divider: Implement and wire up .determine_rate by default") switches clk_divider_ops to implement .determine_rate by default. This breaks composite clocks with multiple parents because clk-composite.c does not use the special handling for mux + divider combinations anymore (that was restricted to rate clocks which only implement .round_rate, but not .determine_rate). Alex reports: This breaks lot of clocks for Rockchip which intensively uses composites, i.e. those clocks will always stay at the initial parent, which in some cases is the XTAL clock and I strongly guess it is the same for other platforms, which use composite clocks having more than one parent (e.g. mediatek, ti ...) Example (RK3399) clk_sdio is set (initialized) with XTAL (24 MHz) as parent in u-boot. It will always stay at this parent, even if the mmc driver sets a rate of 200 MHz (fails, as the nature of things), which should switch it to any of its possible parent PLLs defined in mux_pll_src_cpll_gpll_npll_ppll_upll_24m_p (see clk-rk3399.c) - which never happens. Restore the original behavior by changing the priority of the conditions inside clk-composite.c. Now the special rate + mux case (with rate_ops having a .round_rate - which is still the case for the default clk_divider_ops) is preferred over rate_ops which have .determine_rate defined (and not further considering the mux). Fixes: 69a00fb3d69706 ("clk: divider: Implement and wire up .determine_rate by default") Reported-by: Alex Bee <knaerzche@gmail.com> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> --- drivers/clk/clk-composite.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/clk/clk-composite.c b/drivers/clk/clk-composite.c index c7b97fb0051b..ba8d4d8cf8dd 100644 --- a/drivers/clk/clk-composite.c +++ b/drivers/clk/clk-composite.c @@ -58,11 +58,8 @@ static int clk_composite_determine_rate(struct clk_hw *hw, long rate; int i; - if (rate_hw && rate_ops && rate_ops->determine_rate) { - __clk_hw_set_clk(rate_hw, hw); - return rate_ops->determine_rate(rate_hw, req); - } else if (rate_hw && rate_ops && rate_ops->round_rate && - mux_hw && mux_ops && mux_ops->set_parent) { + if (rate_hw && rate_ops && rate_ops->round_rate && + mux_hw && mux_ops && mux_ops->set_parent) { req->best_parent_hw = NULL; if (clk_hw_get_flags(hw) & CLK_SET_RATE_NO_REPARENT) { @@ -107,6 +104,9 @@ static int clk_composite_determine_rate(struct clk_hw *hw, req->rate = best_rate; return 0; + } else if (rate_hw && rate_ops && rate_ops->determine_rate) { + __clk_hw_set_clk(rate_hw, hw); + return rate_ops->determine_rate(rate_hw, req); } else if (mux_hw && mux_ops && mux_ops->determine_rate) { __clk_hw_set_clk(mux_hw, hw); return mux_ops->determine_rate(mux_hw, req); -- 2.33.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2021-10-16 10:50 UTC|newest] Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-10-16 10:50 [PATCH clk-fixes v1 0/2] Fix clk-composite to support .determine_rate Martin Blumenstingl 2021-10-16 10:50 ` Martin Blumenstingl 2021-10-16 10:50 ` Martin Blumenstingl [this message] 2021-10-16 10:50 ` [PATCH clk-fixes v1 1/2] clk: composite: Also consider .determine_rate for rate + mux composites Martin Blumenstingl 2021-10-18 20:01 ` Stephen Boyd 2021-10-18 20:01 ` Stephen Boyd 2021-10-27 22:47 ` Alex Bee 2021-10-27 22:47 ` Alex Bee 2021-10-29 6:43 ` Stephen Boyd 2021-10-29 6:43 ` Stephen Boyd 2021-10-16 10:50 ` [PATCH clk-fixes v1 2/2] clk: composite: Use rate_ops.determine_rate when also a mux is available Martin Blumenstingl 2021-10-16 10:50 ` Martin Blumenstingl 2021-10-18 20:01 ` Stephen Boyd 2021-10-18 20:01 ` Stephen Boyd 2021-10-16 11:50 ` [PATCH clk-fixes v1 0/2] Fix clk-composite to support .determine_rate Alex Bee 2021-10-16 11:50 ` Alex Bee 2021-10-17 16:15 ` Chen-Yu Tsai 2021-10-17 16:15 ` Chen-Yu Tsai
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