From: Srinivas Pandruvada Date: Mon, 5 May 2025 20:27:22 +0000 (-0700) Subject: platform/x86: ISST: Do Not Restore SST MSRs on CPU Online Operation X-Git-Url: http://git.monstr.eu/?a=commitdiff_plain;h=c935ddfe65da020f5896fa58746fc7a57a876df3;p=linux-2.6-microblaze.git platform/x86: ISST: Do Not Restore SST MSRs on CPU Online Operation During CPU offline/online operations, the hardware retains MSR settings. Even if all CPUs are offlined, the package does not lose its MSR settings. Therefore, it is unnecessary to restore MSRs which are modified during the online operation, and this extra step can be removed. Signed-off-by: Srinivas Pandruvada Link: https://lore.kernel.org/r/20250505202722.1048675-1-srinivas.pandruvada@linux.intel.com Reviewed-by: Ilpo Järvinen Signed-off-by: Ilpo Järvinen --- diff --git a/drivers/platform/x86/intel/speed_select_if/isst_if_common.c b/drivers/platform/x86/intel/speed_select_if/isst_if_common.c index 31239a93dd71..3c4198ce17f2 100644 --- a/drivers/platform/x86/intel/speed_select_if/isst_if_common.c +++ b/drivers/platform/x86/intel/speed_select_if/isst_if_common.c @@ -198,25 +198,6 @@ void isst_resume_common(void) } EXPORT_SYMBOL_GPL(isst_resume_common); -static void isst_restore_msr_local(int cpu) -{ - struct isst_cmd *sst_cmd; - int i; - - mutex_lock(&isst_hash_lock); - for (i = 0; i < ARRAY_SIZE(punit_msr_white_list); ++i) { - if (!punit_msr_white_list[i]) - break; - - hash_for_each_possible(isst_hash, sst_cmd, hnode, - punit_msr_white_list[i]) { - if (!sst_cmd->mbox_cmd_type && sst_cmd->cpu == cpu) - wrmsrl_safe(sst_cmd->cmd, sst_cmd->data); - } - } - mutex_unlock(&isst_hash_lock); -} - /** * isst_if_mbox_cmd_invalid() - Check invalid mailbox commands * @cmd: Pointer to the command structure to verify. @@ -434,8 +415,6 @@ static int isst_if_cpu_online(unsigned int cpu) set_punit_id: isst_cpu_info[cpu].punit_cpu_id = data; - isst_restore_msr_local(cpu); - return 0; }