[PATCH v8 5/5] arm64: dts: qcom: msm8998: reserve potentially inaccessible clocks
From: <hidden>
Date: 2022-02-20 21:23:36
Also in:
linux-arm-msm, linux-clk
Subsystem:
arm/qualcomm mailing list, arm/qualcomm support, the rest · Maintainers:
Bjorn Andersson, Konrad Dybcio, Linus Torvalds
From: Michael Srba <redacted> With the gcc driver now being more complete and describing clocks which might not always be write-accessible to the OS, conservatively specify all such clocks as protected in the SoC dts. The board dts - or even user-supplied dts - can override this property to reflect the actual configuration. Signed-off-by: Michael Srba <redacted> --- CHANGES: - v2: add this patch - v3: fix missing Signed-off-by - v4: add a proper explanation as per review, (hopefully) fix the subject and commit message - v5: none - v6: none - v7: none - v8: none --- arch/arm64/boot/dts/qcom/msm8998.dtsi | 15 +++++++++++++++ 1 file changed, 15 insertions(+)
diff --git a/arch/arm64/boot/dts/qcom/msm8998.dtsi b/arch/arm64/boot/dts/qcom/msm8998.dtsi
index f273bc1ff629..16dccf9d881e 100644
--- a/arch/arm64/boot/dts/qcom/msm8998.dtsi
+++ b/arch/arm64/boot/dts/qcom/msm8998.dtsi@@ -863,6 +863,21 @@ gcc: clock-controller@100000 { clock-names = "xo", "sleep_clk"; clocks = <&xo>, <&sleep_clk>; + + /* + * The hypervisor typically configures the memory region where these clocks + * reside as read-only for the HLOS. If the HLOS tried to enable or disable + * these clocks on a device with such configuration (e.g. because they are + * enabled but unused during boot-up), the device will most likely decide + * to reboot. + * In light of that, we are conservative here and we list all such clocks + * as protected. The board dts (or a user-supplied dts) can override the + * list of protected clocks if it differs from the norm, and it is in fact + * desired for the HLOS to manage these clocks + */ + protected-clocks = <AGGRE2_SNOC_NORTH_AXI>, + <SSC_XO>, + <SSC_CNOC_AHBS_CLK>; }; rpm_msg_ram: sram@778000 {
--
2.34.1