From: Stephan Gerhold stephan@gerhold.net
[ Upstream commit 0ee30ace67e425ab83a1673bf51f50b577328cf9 ]
At the moment, the "qcom-spm-cpuidle" platform device is always created, even if none of the CPUs is actually managed by the SPM. On non-qcom platforms this will result in infinite probe-deferral due to the failing qcom_scm_is_available() call.
To avoid this, look through the CPU DT nodes and check if there is actually any CPU managed by a SPM (as indicated by the qcom,saw property). It should also be available because e.g. MSM8916 has qcom,saw defined but it's typically not enabled with ARM64/PSCI firmwares.
This is needed in preparation of a follow-up change that calls qcom_scm_set_warm_boot_addr() a single time before registering any cpuidle drivers. Otherwise this call might be made even on devices that have this driver enabled but actually make use of PSCI.
Fixes: 60f3692b5f0b ("cpuidle: qcom_spm: Detach state machine from main SPM handling") Reported-by: Marek Szyprowski m.szyprowski@samsung.com Link: https://lore.kernel.org/r/86e3e09f-a8d7-3dff-3fc6-ddd7d30c5d78@samsung.com/ Signed-off-by: Stephan Gerhold stephan@gerhold.net Tested-by: Marek Szyprowski m.szyprowski@samsung.com Acked-by: Daniel Lezcano daniel.lezcano@linaro.org Signed-off-by: Bjorn Andersson bjorn.andersson@linaro.org Link: https://lore.kernel.org/r/20211201130505.257379-2-stephan@gerhold.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/cpuidle/cpuidle-qcom-spm.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+)
diff --git a/drivers/cpuidle/cpuidle-qcom-spm.c b/drivers/cpuidle/cpuidle-qcom-spm.c index 01e77913a414..5f27dcc6c110 100644 --- a/drivers/cpuidle/cpuidle-qcom-spm.c +++ b/drivers/cpuidle/cpuidle-qcom-spm.c @@ -155,6 +155,22 @@ static struct platform_driver spm_cpuidle_driver = { }, };
+static bool __init qcom_spm_find_any_cpu(void) +{ + struct device_node *cpu_node, *saw_node; + + for_each_of_cpu_node(cpu_node) { + saw_node = of_parse_phandle(cpu_node, "qcom,saw", 0); + if (of_device_is_available(saw_node)) { + of_node_put(saw_node); + of_node_put(cpu_node); + return true; + } + of_node_put(saw_node); + } + return false; +} + static int __init qcom_spm_cpuidle_init(void) { struct platform_device *pdev; @@ -164,6 +180,10 @@ static int __init qcom_spm_cpuidle_init(void) if (ret) return ret;
+ /* Make sure there is actually any CPU managed by the SPM */ + if (!qcom_spm_find_any_cpu()) + return 0; + pdev = platform_device_register_simple("qcom-spm-cpuidle", -1, NULL, 0); if (IS_ERR(pdev)) {