From: "André Draszik" <andre.draszik@linaro.org> To: peter.griffin@linaro.org, robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org Cc: linux-kernel@vger.kernel.org, kernel-team@android.com, tudor.ambarus@linaro.org, willmcvicker@google.com, semen.protsenko@linaro.org, alim.akhtar@samsung.com, s.nawrocki@samsung.com, tomasz.figa@gmail.com, cw00.choi@samsung.com, mturquette@baylibre.com, sboyd@kernel.org, linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-clk@vger.kernel.org, devicetree@vger.kernel.org Subject: [PATCH 5/5] clk: samsung: gs101: don't mark non-essential clocks as critical Date: Sat, 27 Jan 2024 00:35:54 +0000 [thread overview] Message-ID: <20240127003607.501086-6-andre.draszik@linaro.org> (raw) In-Reply-To: <20240127003607.501086-1-andre.draszik@linaro.org> The peric0_top1_ipclk_0 and peric0_top1_pclk_0 are the clocks going to peric0/uart_usi, with pclk being the bus clock. Without pclk running, any bus access will hang. Unfortunately, in commit d97b6c902a40 ("arm64: dts: exynos: gs101: update USI UART to use peric0 clocks") the gs101 DT ended up specifying an incorrect pclkk in the respective node and instead the two clocks here were marked as critical. We have fixed the gs101 DT and can therefore drop this incorrect work-around here, the uart driver will claim these clocks as needed. Note that this commit has the side-effect of causing earlycon to stop to work sometime into the boot for two reasons: * peric0_top1_ipclk_0 requires its parent gout_cmu_peric0_ip to be running, but because earlycon doesn't deal with clocks that parent will be disabled when none of the other drivers that actually deal with clocks correctly require it to be running and the real serial driver (which does deal with clocks) hasn't taken over yet * hand-over between earlycon and serial driver appears to be fragile and clocks get enabled and disabled a few times, which also causes register access to hang while earlycon is still active Nonetheless we shouldn't keep these clocks running unconditionally just for earlycon. Clocks should be disabled where possible. If earlycon is required in the future, e.g. for debug, this commit can simply be reverted (locally!). Fixes: 893f133a040b ("clk: samsung: gs101: add support for cmu_peric0") Signed-off-by: André Draszik <andre.draszik@linaro.org> --- drivers/clk/samsung/clk-gs101.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/clk/samsung/clk-gs101.c b/drivers/clk/samsung/clk-gs101.c index 61bb0dcf84ee..5c338ac9231c 100644 --- a/drivers/clk/samsung/clk-gs101.c +++ b/drivers/clk/samsung/clk-gs101.c @@ -2982,20 +2982,18 @@ static const struct samsung_gate_clock peric0_gate_clks[] __initconst = { "gout_peric0_peric0_top0_pclk_9", "mout_peric0_bus_user", CLK_CON_GAT_GOUT_BLK_PERIC0_UID_PERIC0_TOP0_IPCLKPORT_PCLK_9, 21, 0, 0), - /* Disabling this clock makes the system hang. Mark the clock as critical. */ GATE(CLK_GOUT_PERIC0_PERIC0_TOP1_IPCLK_0, "gout_peric0_peric0_top1_ipclk_0", "dout_peric0_usi0_uart", CLK_CON_GAT_GOUT_BLK_PERIC0_UID_PERIC0_TOP1_IPCLKPORT_IPCLK_0, - 21, CLK_IS_CRITICAL, 0), + 21, 0, 0), GATE(CLK_GOUT_PERIC0_PERIC0_TOP1_IPCLK_2, "gout_peric0_peric0_top1_ipclk_2", "dout_peric0_usi14_usi", CLK_CON_GAT_GOUT_BLK_PERIC0_UID_PERIC0_TOP1_IPCLKPORT_IPCLK_2, 21, 0, 0), - /* Disabling this clock makes the system hang. Mark the clock as critical. */ GATE(CLK_GOUT_PERIC0_PERIC0_TOP1_PCLK_0, "gout_peric0_peric0_top1_pclk_0", "mout_peric0_bus_user", CLK_CON_GAT_GOUT_BLK_PERIC0_UID_PERIC0_TOP1_IPCLKPORT_PCLK_0, - 21, CLK_IS_CRITICAL, 0), + 21, 0, 0), GATE(CLK_GOUT_PERIC0_PERIC0_TOP1_PCLK_2, "gout_peric0_peric0_top1_pclk_2", "mout_peric0_bus_user", CLK_CON_GAT_GOUT_BLK_PERIC0_UID_PERIC0_TOP1_IPCLKPORT_PCLK_2, -- 2.43.0.429.g432eaa2c6b-goog
WARNING: multiple messages have this Message-ID (diff)
From: "André Draszik" <andre.draszik@linaro.org> To: peter.griffin@linaro.org, robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org Cc: linux-kernel@vger.kernel.org, kernel-team@android.com, tudor.ambarus@linaro.org, willmcvicker@google.com, semen.protsenko@linaro.org, alim.akhtar@samsung.com, s.nawrocki@samsung.com, tomasz.figa@gmail.com, cw00.choi@samsung.com, mturquette@baylibre.com, sboyd@kernel.org, linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-clk@vger.kernel.org, devicetree@vger.kernel.org Subject: [PATCH 5/5] clk: samsung: gs101: don't mark non-essential clocks as critical Date: Sat, 27 Jan 2024 00:35:54 +0000 [thread overview] Message-ID: <20240127003607.501086-6-andre.draszik@linaro.org> (raw) In-Reply-To: <20240127003607.501086-1-andre.draszik@linaro.org> The peric0_top1_ipclk_0 and peric0_top1_pclk_0 are the clocks going to peric0/uart_usi, with pclk being the bus clock. Without pclk running, any bus access will hang. Unfortunately, in commit d97b6c902a40 ("arm64: dts: exynos: gs101: update USI UART to use peric0 clocks") the gs101 DT ended up specifying an incorrect pclkk in the respective node and instead the two clocks here were marked as critical. We have fixed the gs101 DT and can therefore drop this incorrect work-around here, the uart driver will claim these clocks as needed. Note that this commit has the side-effect of causing earlycon to stop to work sometime into the boot for two reasons: * peric0_top1_ipclk_0 requires its parent gout_cmu_peric0_ip to be running, but because earlycon doesn't deal with clocks that parent will be disabled when none of the other drivers that actually deal with clocks correctly require it to be running and the real serial driver (which does deal with clocks) hasn't taken over yet * hand-over between earlycon and serial driver appears to be fragile and clocks get enabled and disabled a few times, which also causes register access to hang while earlycon is still active Nonetheless we shouldn't keep these clocks running unconditionally just for earlycon. Clocks should be disabled where possible. If earlycon is required in the future, e.g. for debug, this commit can simply be reverted (locally!). Fixes: 893f133a040b ("clk: samsung: gs101: add support for cmu_peric0") Signed-off-by: André Draszik <andre.draszik@linaro.org> --- drivers/clk/samsung/clk-gs101.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/clk/samsung/clk-gs101.c b/drivers/clk/samsung/clk-gs101.c index 61bb0dcf84ee..5c338ac9231c 100644 --- a/drivers/clk/samsung/clk-gs101.c +++ b/drivers/clk/samsung/clk-gs101.c @@ -2982,20 +2982,18 @@ static const struct samsung_gate_clock peric0_gate_clks[] __initconst = { "gout_peric0_peric0_top0_pclk_9", "mout_peric0_bus_user", CLK_CON_GAT_GOUT_BLK_PERIC0_UID_PERIC0_TOP0_IPCLKPORT_PCLK_9, 21, 0, 0), - /* Disabling this clock makes the system hang. Mark the clock as critical. */ GATE(CLK_GOUT_PERIC0_PERIC0_TOP1_IPCLK_0, "gout_peric0_peric0_top1_ipclk_0", "dout_peric0_usi0_uart", CLK_CON_GAT_GOUT_BLK_PERIC0_UID_PERIC0_TOP1_IPCLKPORT_IPCLK_0, - 21, CLK_IS_CRITICAL, 0), + 21, 0, 0), GATE(CLK_GOUT_PERIC0_PERIC0_TOP1_IPCLK_2, "gout_peric0_peric0_top1_ipclk_2", "dout_peric0_usi14_usi", CLK_CON_GAT_GOUT_BLK_PERIC0_UID_PERIC0_TOP1_IPCLKPORT_IPCLK_2, 21, 0, 0), - /* Disabling this clock makes the system hang. Mark the clock as critical. */ GATE(CLK_GOUT_PERIC0_PERIC0_TOP1_PCLK_0, "gout_peric0_peric0_top1_pclk_0", "mout_peric0_bus_user", CLK_CON_GAT_GOUT_BLK_PERIC0_UID_PERIC0_TOP1_IPCLKPORT_PCLK_0, - 21, CLK_IS_CRITICAL, 0), + 21, 0, 0), GATE(CLK_GOUT_PERIC0_PERIC0_TOP1_PCLK_2, "gout_peric0_peric0_top1_pclk_2", "mout_peric0_bus_user", CLK_CON_GAT_GOUT_BLK_PERIC0_UID_PERIC0_TOP1_IPCLKPORT_PCLK_2, -- 2.43.0.429.g432eaa2c6b-goog _______________________________________________ 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:[~2024-01-27 0:37 UTC|newest] Thread overview: 56+ messages / expand[flat|nested] mbox.gz Atom feed top 2024-01-27 0:35 gs101 oriole: peripheral block 0 (peric0) fixes André Draszik 2024-01-27 0:35 ` André Draszik 2024-01-27 0:35 ` [PATCH 1/5] clk: samsung: gs101: gpio_peric0_pclk needs to be kept on André Draszik 2024-01-27 0:35 ` André Draszik 2024-01-27 3:06 ` Sam Protsenko 2024-01-27 3:06 ` Sam Protsenko 2024-01-27 3:51 ` Tudor Ambarus 2024-01-27 3:51 ` Tudor Ambarus 2024-01-29 12:54 ` Peter Griffin 2024-01-29 12:54 ` Peter Griffin 2024-01-27 0:35 ` [PATCH 2/5] arm64: dts: exynos: gs101: fix usi8 default mode André Draszik 2024-01-27 0:35 ` André Draszik 2024-01-27 3:05 ` Sam Protsenko 2024-01-27 3:05 ` Sam Protsenko 2024-01-27 3:48 ` Tudor Ambarus 2024-01-27 3:48 ` Tudor Ambarus 2024-01-29 9:48 ` Peter Griffin 2024-01-29 9:48 ` Peter Griffin 2024-01-27 0:35 ` [PATCH 3/5] arm64: dts: exynos: gs101: use correct clocks for usi8 André Draszik 2024-01-27 0:35 ` André Draszik 2024-01-27 3:22 ` Sam Protsenko 2024-01-27 3:22 ` Sam Protsenko 2024-01-27 4:00 ` Tudor Ambarus 2024-01-27 4:00 ` Tudor Ambarus 2024-01-29 16:33 ` Tudor Ambarus 2024-01-29 16:33 ` Tudor Ambarus 2024-01-29 14:01 ` André Draszik 2024-01-29 14:01 ` André Draszik 2024-01-27 0:35 ` [PATCH 4/5] arm64: dts: exynos: gs101: use correct clocks for usi_uart André Draszik 2024-01-27 0:35 ` André Draszik 2024-01-27 1:37 ` André Draszik 2024-01-27 1:37 ` André Draszik 2024-01-27 3:23 ` Sam Protsenko 2024-01-27 3:23 ` Sam Protsenko 2024-01-27 4:03 ` Tudor Ambarus 2024-01-27 4:03 ` Tudor Ambarus 2024-01-29 16:39 ` Tudor Ambarus 2024-01-29 16:39 ` Tudor Ambarus 2024-01-27 0:35 ` André Draszik [this message] 2024-01-27 0:35 ` [PATCH 5/5] clk: samsung: gs101: don't mark non-essential clocks as critical André Draszik 2024-01-27 1:38 ` André Draszik 2024-01-27 1:38 ` André Draszik 2024-01-27 3:30 ` Sam Protsenko 2024-01-27 3:30 ` Sam Protsenko 2024-01-29 14:37 ` André Draszik 2024-01-29 14:37 ` André Draszik 2024-01-29 19:16 ` Sam Protsenko 2024-01-29 19:16 ` Sam Protsenko 2024-01-30 9:31 ` André Draszik 2024-01-30 9:31 ` André Draszik 2024-01-30 9:39 ` Tudor Ambarus 2024-01-30 9:39 ` Tudor Ambarus 2024-01-29 16:44 ` Tudor Ambarus 2024-01-29 16:44 ` Tudor Ambarus 2024-01-27 3:01 ` gs101 oriole: peripheral block 0 (peric0) fixes Sam Protsenko 2024-01-27 3:01 ` Sam Protsenko
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20240127003607.501086-6-andre.draszik@linaro.org \ --to=andre.draszik@linaro.org \ --cc=alim.akhtar@samsung.com \ --cc=conor+dt@kernel.org \ --cc=cw00.choi@samsung.com \ --cc=devicetree@vger.kernel.org \ --cc=kernel-team@android.com \ --cc=krzysztof.kozlowski+dt@linaro.org \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=linux-clk@vger.kernel.org \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-samsung-soc@vger.kernel.org \ --cc=mturquette@baylibre.com \ --cc=peter.griffin@linaro.org \ --cc=robh+dt@kernel.org \ --cc=s.nawrocki@samsung.com \ --cc=sboyd@kernel.org \ --cc=semen.protsenko@linaro.org \ --cc=tomasz.figa@gmail.com \ --cc=tudor.ambarus@linaro.org \ --cc=willmcvicker@google.com \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.