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authorStephan Gerhold <stephan@gerhold.net>2021-12-01 16:05:02 +0300
committerBjorn Andersson <bjorn.andersson@linaro.org>2022-02-04 06:54:48 +0300
commit0ee30ace67e425ab83a1673bf51f50b577328cf9 (patch)
tree10bbf34432029298cd7cd660735d6f16d3522a73 /drivers/cpuidle
parent5cef9b48458dee48c62f61deca4d3df87b66b52b (diff)
downloadlinux-0ee30ace67e425ab83a1673bf51f50b577328cf9.tar.xz
cpuidle: qcom-spm: Check if any CPU is managed by SPM
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
Diffstat (limited to 'drivers/cpuidle')
-rw-r--r--drivers/cpuidle/cpuidle-qcom-spm.c20
1 files changed, 20 insertions, 0 deletions
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)) {