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 <dbrazdil@xxxxxxxxxx>
---
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
_______________________________________________
kvmarm mailing list
kvmarm@xxxxxxxxxxxxxxxxxxxxx
https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
