Re: [PATCH v11 11/40] arm64/sme: Identify supported SME vector lengths at boot

On Mon, Feb 07, 2022 at 03:20:40PM +0000, Mark Brown wrote:

@@ -977,6 +984,14 @@ void __init init_cpu_features(struct cpuinfo_arm64 *info) vec_init_vq_map(ARM64_VEC_SVE); }

• if (id_aa64pfr1_sme(info->reg_id_aa64pfr1)) {

• init_cpu_ftr_reg(SYS_SMCR_EL1, info->reg_smcr);
  

• if (IS_ENABLED(CONFIG_ARM64_SME)) {
  

• 	sme_kernel_enable(NULL);
  

• 	vec_init_vq_map(ARM64_VEC_SME);
  

• }
  

• }

Why do we need to call sme_kernel_enable() here? It's called again later via the cpufeature framework. I guess you need the CPACR_EL1 setup but we don't seem to do this for SVE.