To ensure successful builds when CONFIG_IMX_SCMI_CPU_DRV is not enabled,
this patch adds static inline stub implementations for the following
functions:

  - scmi_imx_cpu_start()
  - scmi_imx_cpu_started()
  - scmi_imx_cpu_reset_vector_set()

These stubs return -EOPNOTSUPP to indicate that the functionality is not
supported in the current configuration. This avoids potential build or
link errors in code that conditionally calls these functions based on
feature availability.

Fixes: 1055faa5d660 ("firmware: imx: Add i.MX95 SCMI CPU driver")
Signed-off-by: Peng Fan <peng.fan@nxp.com>
---
 include/linux/firmware/imx/sm.h | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/include/linux/firmware/imx/sm.h b/include/linux/firmware/imx/sm.h
index f2a72177bb37c1d46145a60710e3809641e0f5a2..a33b45027356751f4b8ad9b9136f0dd302a82520 100644
--- a/include/linux/firmware/imx/sm.h
+++ b/include/linux/firmware/imx/sm.h
@@ -41,10 +41,28 @@ static inline int scmi_imx_misc_ctrl_set(u32 id, u32 val)
 }
 #endif
 
+#if IS_ENABLED(CONFIG_IMX_SCMI_CPU_DRV)
 int scmi_imx_cpu_start(u32 cpuid, bool start);
 int scmi_imx_cpu_started(u32 cpuid, bool *started);
 int scmi_imx_cpu_reset_vector_set(u32 cpuid, u64 vector, bool start, bool boot,
 				  bool resume);
+#else
+static inline int scmi_imx_cpu_start(u32 cpuid, bool start)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int scmi_imx_cpu_started(u32 cpuid, bool *started)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int scmi_imx_cpu_reset_vector_set(u32 cpuid, u64 vector, bool start,
+						bool boot, bool resume)
+{
+	return -EOPNOTSUPP;
+}
+#endif
 
 enum scmi_imx_lmm_op {
 	SCMI_IMX_LMM_BOOT,

-- 
2.37.1

On Thu, Aug 07, 2025 at 09:47:44AM +0800, Peng Fan wrote:
> To ensure successful builds when CONFIG_IMX_SCMI_CPU_DRV is not enabled,
> this patch adds static inline stub implementations for the following
> functions:
> 
>   - scmi_imx_cpu_start()
>   - scmi_imx_cpu_started()
>   - scmi_imx_cpu_reset_vector_set()
> 
> These stubs return -EOPNOTSUPP to indicate that the functionality is not
> supported in the current configuration. This avoids potential build or
> link errors in code that conditionally calls these functions based on
> feature availability.
> 
> Fixes: 1055faa5d660 ("firmware: imx: Add i.MX95 SCMI CPU driver")
> Signed-off-by: Peng Fan <peng.fan@nxp.com>
> ---
>  include/linux/firmware/imx/sm.h | 18 ++++++++++++++++++
>  1 file changed, 18 insertions(+)
> 
> diff --git a/include/linux/firmware/imx/sm.h b/include/linux/firmware/imx/sm.h
> index f2a72177bb37c1d46145a60710e3809641e0f5a2..a33b45027356751f4b8ad9b9136f0dd302a82520 100644
> --- a/include/linux/firmware/imx/sm.h
> +++ b/include/linux/firmware/imx/sm.h
> @@ -41,10 +41,28 @@ static inline int scmi_imx_misc_ctrl_set(u32 id, u32 val)
>  }
>  #endif
>  
> +#if IS_ENABLED(CONFIG_IMX_SCMI_CPU_DRV)
>  int scmi_imx_cpu_start(u32 cpuid, bool start);
>  int scmi_imx_cpu_started(u32 cpuid, bool *started);
>  int scmi_imx_cpu_reset_vector_set(u32 cpuid, u64 vector, bool start, bool boot,
>  				  bool resume);
> +#else
> +static inline int scmi_imx_cpu_start(u32 cpuid, bool start)
> +{
> +	return -EOPNOTSUPP;
> +}
> +
> +static inline int scmi_imx_cpu_started(u32 cpuid, bool *started)
> +{
> +	return -EOPNOTSUPP;
> +}
> +
> +static inline int scmi_imx_cpu_reset_vector_set(u32 cpuid, u64 vector, bool start,
> +						bool boot, bool resume)
> +{
> +	return -EOPNOTSUPP;
> +}
> +#endif

LGTM.

Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>

Thanks,
Cristian