2022-09-02 13:53:51

by Sudeep Holla

Subject: [PATCH v2 04/10] firmware: arm_ffa: Add support for querying FF-A features

Add support for FFA_FEATURES to discover properties supported at the
FF-A interface. This interface can be used to query:
- If an FF-A interface is implemented by the component at the higher EL,
- If an implemented FF-A interface also implements any optional features
described in its interface definition, and
- Any implementation details exported by an implemented FF-A interface
as described in its interface definition.

Signed-off-by: Sudeep Holla <[email protected]>
---
drivers/firmware/arm_ffa/driver.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)

diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c
index 04e7cbb1b9aa..81b8d578b6ea 100644
--- a/drivers/firmware/arm_ffa/driver.c
+++ b/drivers/firmware/arm_ffa/driver.c
@@ -571,6 +571,32 @@ static int ffa_memory_reclaim(u64 g_handle, u32 flags)
return 0;
}

+static int ffa_features(u32 func_feat_id, u32 input_props,
+ u32 *if_props_1, u32 *if_props_2)
+{
+ ffa_value_t id;
+
+ if (!ARM_SMCCC_IS_FAST_CALL(func_feat_id) && input_props) {
+ pr_err("%s: Invalid Parameters: %x, %x", __func__,
+ func_feat_id, input_props);
+ return ffa_to_linux_errno(FFA_RET_INVALID_PARAMETERS);
+ }
+
+ invoke_ffa_fn((ffa_value_t){
+ .a0 = FFA_FEATURES, .a1 = func_feat_id, .a2 = input_props,
+ }, &id);
+
+ if (id.a0 == FFA_ERROR)
+ return ffa_to_linux_errno((int)id.a2);
+
+ if (if_props_1)
+ *if_props_1 = id.a2;
+ if (if_props_2)
+ *if_props_2 = id.a3;
+
+ return 0;
+}
+
static u32 ffa_api_version_get(void)
{
return drv_info->version;
--
2.37.3

2022-09-07 12:55:20

by Jens Wiklander

Subject: Re: [PATCH v2 04/10] firmware: arm_ffa: Add support for querying FF-A features

On Fri, Sep 2, 2022 at 2:40 PM Sudeep Holla <[email protected]> wrote:
>
> Add support for FFA_FEATURES to discover properties supported at the
> FF-A interface. This interface can be used to query:
> - If an FF-A interface is implemented by the component at the higher EL,
> - If an implemented FF-A interface also implements any optional features
> described in its interface definition, and
> - Any implementation details exported by an implemented FF-A interface
> as described in its interface definition.
>
> Signed-off-by: Sudeep Holla <[email protected]>
> ---
> drivers/firmware/arm_ffa/driver.c | 26 ++++++++++++++++++++++++++
> 1 file changed, 26 insertions(+)

Reviewed-by: Jens Wiklander <[email protected]>

>
> diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c
> index 04e7cbb1b9aa..81b8d578b6ea 100644
> --- a/drivers/firmware/arm_ffa/driver.c
> +++ b/drivers/firmware/arm_ffa/driver.c
> @@ -571,6 +571,32 @@ static int ffa_memory_reclaim(u64 g_handle, u32 flags)
> return 0;
> }
>
> +static int ffa_features(u32 func_feat_id, u32 input_props,
> + u32 *if_props_1, u32 *if_props_2)
> +{
> + ffa_value_t id;
> +
> + if (!ARM_SMCCC_IS_FAST_CALL(func_feat_id) && input_props) {
> + pr_err("%s: Invalid Parameters: %x, %x", __func__,
> + func_feat_id, input_props);
> + return ffa_to_linux_errno(FFA_RET_INVALID_PARAMETERS);
> + }
> +
> + invoke_ffa_fn((ffa_value_t){
> + .a0 = FFA_FEATURES, .a1 = func_feat_id, .a2 = input_props,
> + }, &id);
> +
> + if (id.a0 == FFA_ERROR)
> + return ffa_to_linux_errno((int)id.a2);
> +
> + if (if_props_1)
> + *if_props_1 = id.a2;
> + if (if_props_2)
> + *if_props_2 = id.a3;
> +
> + return 0;
> +}
> +
> static u32 ffa_api_version_get(void)
> {
> return drv_info->version;
> --
> 2.37.3
>