[PATCH v1 01/24] psci: Accessor for configured PSCI version
From: David Brazdil <hidden>
Date: 2020-11-09 11:32:49
Also in:
kvmarm, lkml
Subsystem:
power state coordination interface (psci), the rest · Maintainers:
Mark Rutland, Lorenzo Pieralisi, Linus Torvalds
The version of PSCI that the kernel should use to communicate with firmware is typically obtained from probing PSCI_VERSION. However, that doesn't work for PSCI v0.1 where the host gets the information from DT/ACPI, or if PSCI is not supported / was disabled. KVM's host PSCI proxy needs to be configured with the same version used by the host driver. Expose the PSCI version used by the host with a read-only accessor. Signed-off-by: David Brazdil <redacted> --- drivers/firmware/psci/psci.c | 11 +++++++++++ include/linux/psci.h | 8 ++++++++ 2 files changed, 19 insertions(+)
diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c
index 00af99b6f97c..bc1b2d60fdbf 100644
--- a/drivers/firmware/psci/psci.c
+++ b/drivers/firmware/psci/psci.c@@ -49,6 +49,13 @@ static int resident_cpu = -1; struct psci_operations psci_ops; static enum arm_smccc_conduit psci_conduit = SMCCC_CONDUIT_NONE; +static int driver_version = PSCI_VERSION(0, 0); + +int psci_driver_version(void) +{ + return driver_version; +} + bool psci_tos_resident_on(int cpu) { return cpu == resident_cpu;
@@ -461,6 +468,8 @@ static int __init psci_probe(void) return -EINVAL; } + driver_version = ver; + psci_0_2_set_functions(); psci_init_migrate();
@@ -514,6 +523,8 @@ static int __init psci_0_1_init(struct device_node *np) pr_info("Using PSCI v0.1 Function IDs from DT\n"); + driver_version = PSCI_VERSION(0, 1); + if (!of_property_read_u32(np, "cpu_suspend", &id)) { psci_function_id[PSCI_FN_CPU_SUSPEND] = id; psci_ops.cpu_suspend = psci_cpu_suspend;
diff --git a/include/linux/psci.h b/include/linux/psci.h
index 2a1bfb890e58..5b5dcf176aa6 100644
--- a/include/linux/psci.h
+++ b/include/linux/psci.h@@ -21,6 +21,14 @@ bool psci_power_state_is_valid(u32 state); int psci_set_osi_mode(bool enable); bool psci_has_osi_support(void); +/** + * The version of the PSCI specification followed by the driver. + * This is equivalent to calling PSCI_VERSION except: + * (a) it also works for PSCI v0.1, which does not support PSCI_VERSION, and + * (b) it is set to v0.0 if the PSCI driver was not initialized. + */ +int psci_driver_version(void); + struct psci_operations { u32 (*get_version)(void); int (*cpu_suspend)(u32 state, unsigned long entry_point);
--
2.29.2.222.g5d2a92d10f8-goog
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