From: Michael Srba <michael.srba@xxxxxxxxx>
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 <Michael.Srba@xxxxxxxxx>
---
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
---
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
