2020-11-26 15:57:14

by David Brazdil

Subject: [PATCH v3 01/23] psci: Support psci_ops.get_version for v0.1

KVM's host PSCI SMC filter needs to be aware of the PSCI version of the
system but currently it is impossible to distinguish between v0.1 and
PSCI disabled because both have get_version == NULL.

Populate get_version for v0.1 with a function that returns a constant.

psci_opt.get_version is currently unused so this has no effect on
existing functionality.

Signed-off-by: David Brazdil <[email protected]>
---
drivers/firmware/psci/psci.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c
index 00af99b6f97c..213c68418a65 100644
--- a/drivers/firmware/psci/psci.c
+++ b/drivers/firmware/psci/psci.c
@@ -146,6 +146,11 @@ static int psci_to_linux_errno(int errno)
return -EINVAL;
}

+static u32 psci_get_version_0_1(void)
+{
+ return PSCI_VERSION(0, 1);
+}
+
static u32 psci_get_version(void)
{
return invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
@@ -514,6 +519,8 @@ static int __init psci_0_1_init(struct device_node *np)

pr_info("Using PSCI v0.1 Function IDs from DT\n");

+ psci_ops.get_version = psci_get_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;
--
2.29.2.454.gaff20da3a2-goog

2020-11-26 17:25:31

by Mark Rutland

Subject: Re: [PATCH v3 01/23] psci: Support psci_ops.get_version for v0.1

On Thu, Nov 26, 2020 at 03:53:59PM +0000, David Brazdil wrote:
> KVM's host PSCI SMC filter needs to be aware of the PSCI version of the
> system but currently it is impossible to distinguish between v0.1 and
> PSCI disabled because both have get_version == NULL.
>
> Populate get_version for v0.1 with a function that returns a constant.
>
> psci_opt.get_version is currently unused so this has no effect on
> existing functionality.
>
> Signed-off-by: David Brazdil <[email protected]>
> ---
> drivers/firmware/psci/psci.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c
> index 00af99b6f97c..213c68418a65 100644
> --- a/drivers/firmware/psci/psci.c
> +++ b/drivers/firmware/psci/psci.c
> @@ -146,6 +146,11 @@ static int psci_to_linux_errno(int errno)
> return -EINVAL;
> }
>
> +static u32 psci_get_version_0_1(void)
> +{
> + return PSCI_VERSION(0, 1);
> +}

Elsewhere in this file we've used a psci_${MAJOR}_${MINOR}_* naming
scheme.

To match that, I'd prefer we call this psci_0_1_get_version(), and
rename psci_get_version() to psci_0_2_get_version().

With that:

Acked-by: Mark Rutland <[email protected]>

Thanks,
Mark.

> +
> static u32 psci_get_version(void)
> {
> return invoke_psci_fn(PSCI_0_2_FN_PSCI_VERSION, 0, 0, 0);
> @@ -514,6 +519,8 @@ static int __init psci_0_1_init(struct device_node *np)
>
> pr_info("Using PSCI v0.1 Function IDs from DT\n");
>
> + psci_ops.get_version = psci_get_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;
> --
> 2.29.2.454.gaff20da3a2-goog
>