From 9a8fa00dad3c7b260071f2f220cfb00505372c40 Mon Sep 17 00:00:00 2001 From: Maulik Shah Date: Mon, 3 Jul 2023 14:25:53 +0530 Subject: [PATCH 1/2] cpuidle: dt_idle_genpd: Add helper function to remove genpd topology Genpd parent and child domain topology created using dt_idle_pd_init_topology() needs to be removed during error cases. Add new helper function dt_idle_pd_remove_topology() for same. Cc: stable@vger.kernel.org Reviewed-by: Ulf Hanssson Signed-off-by: Maulik Shah Signed-off-by: Ulf Hansson --- drivers/cpuidle/dt_idle_genpd.c | 24 ++++++++++++++++++++++++ drivers/cpuidle/dt_idle_genpd.h | 7 +++++++ 2 files changed, 31 insertions(+) diff --git a/drivers/cpuidle/dt_idle_genpd.c b/drivers/cpuidle/dt_idle_genpd.c index b37165514d4e..1af63c189039 100644 --- a/drivers/cpuidle/dt_idle_genpd.c +++ b/drivers/cpuidle/dt_idle_genpd.c @@ -152,6 +152,30 @@ int dt_idle_pd_init_topology(struct device_node *np) return 0; } +int dt_idle_pd_remove_topology(struct device_node *np) +{ + struct device_node *node; + struct of_phandle_args child, parent; + int ret; + + for_each_child_of_node(np, node) { + if (of_parse_phandle_with_args(node, "power-domains", + "#power-domain-cells", 0, &parent)) + continue; + + child.np = node; + child.args_count = 0; + ret = of_genpd_remove_subdomain(&parent, &child); + of_node_put(parent.np); + if (ret) { + of_node_put(node); + return ret; + } + } + + return 0; +} + struct device *dt_idle_attach_cpu(int cpu, const char *name) { struct device *dev; diff --git a/drivers/cpuidle/dt_idle_genpd.h b/drivers/cpuidle/dt_idle_genpd.h index a95483d08a02..3be1f70f55b5 100644 --- a/drivers/cpuidle/dt_idle_genpd.h +++ b/drivers/cpuidle/dt_idle_genpd.h @@ -14,6 +14,8 @@ struct generic_pm_domain *dt_idle_pd_alloc(struct device_node *np, int dt_idle_pd_init_topology(struct device_node *np); +int dt_idle_pd_remove_topology(struct device_node *np); + struct device *dt_idle_attach_cpu(int cpu, const char *name); void dt_idle_detach_cpu(struct device *dev); @@ -36,6 +38,11 @@ static inline int dt_idle_pd_init_topology(struct device_node *np) return 0; } +static inline int dt_idle_pd_remove_topology(struct device_node *np) +{ + return 0; +} + static inline struct device *dt_idle_attach_cpu(int cpu, const char *name) { return NULL; From 12acb348fa4528a4203edf1cce7a3be2c9af2279 Mon Sep 17 00:00:00 2001 From: Maulik Shah Date: Mon, 3 Jul 2023 14:25:54 +0530 Subject: [PATCH 2/2] cpuidle: psci: Move enabling OSI mode after power domains creation A switch from OSI to PC mode is only possible if all CPUs other than the calling one are OFF, either through a call to CPU_OFF or not yet booted. Currently OSI mode is enabled before power domains are created. In cases where CPUidle states are not using hierarchical CPU topology the bail out path tries to switch back to PC mode which gets denied by firmware since other CPUs are online at this point and creates inconsistent state as firmware is in OSI mode and Linux in PC mode. This change moves enabling OSI mode after power domains are created, this would makes sure that hierarchical CPU topology is used before switching firmware to OSI mode. Cc: stable@vger.kernel.org Fixes: 70c179b49870 ("cpuidle: psci: Allow PM domain to be initialized even if no OSI mode") Signed-off-by: Maulik Shah Reviewed-by: Ulf Hansson Signed-off-by: Ulf Hansson --- drivers/cpuidle/cpuidle-psci-domain.c | 39 +++++++++------------------ 1 file changed, 13 insertions(+), 26 deletions(-) diff --git a/drivers/cpuidle/cpuidle-psci-domain.c b/drivers/cpuidle/cpuidle-psci-domain.c index c2d6d9c3c930..b88af1262f1a 100644 --- a/drivers/cpuidle/cpuidle-psci-domain.c +++ b/drivers/cpuidle/cpuidle-psci-domain.c @@ -120,20 +120,6 @@ static void psci_pd_remove(void) } } -static bool psci_pd_try_set_osi_mode(void) -{ - int ret; - - if (!psci_has_osi_support()) - return false; - - ret = psci_set_osi_mode(true); - if (ret) - return false; - - return true; -} - static void psci_cpuidle_domain_sync_state(struct device *dev) { /* @@ -152,15 +138,12 @@ static int psci_cpuidle_domain_probe(struct platform_device *pdev) { struct device_node *np = pdev->dev.of_node; struct device_node *node; - bool use_osi; + bool use_osi = psci_has_osi_support(); int ret = 0, pd_count = 0; if (!np) return -ENODEV; - /* If OSI mode is supported, let's try to enable it. */ - use_osi = psci_pd_try_set_osi_mode(); - /* * Parse child nodes for the "#power-domain-cells" property and * initialize a genpd/genpd-of-provider pair when it's found. @@ -170,33 +153,37 @@ static int psci_cpuidle_domain_probe(struct platform_device *pdev) continue; ret = psci_pd_init(node, use_osi); - if (ret) - goto put_node; + if (ret) { + of_node_put(node); + goto exit; + } pd_count++; } /* Bail out if not using the hierarchical CPU topology. */ if (!pd_count) - goto no_pd; + return 0; /* Link genpd masters/subdomains to model the CPU topology. */ ret = dt_idle_pd_init_topology(np); if (ret) goto remove_pd; + /* let's try to enable OSI. */ + ret = psci_set_osi_mode(use_osi); + if (ret) + goto remove_pd; + pr_info("Initialized CPU PM domain topology using %s mode\n", use_osi ? "OSI" : "PC"); return 0; -put_node: - of_node_put(node); remove_pd: + dt_idle_pd_remove_topology(np); psci_pd_remove(); +exit: pr_err("failed to create CPU PM domains ret=%d\n", ret); -no_pd: - if (use_osi) - psci_set_osi_mode(false); return ret; }