Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752531AbdGFPHD (ORCPT ); Thu, 6 Jul 2017 11:07:03 -0400 Received: from mail-pg0-f67.google.com ([74.125.83.67]:33686 "EHLO mail-pg0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751861AbdGFPHB (ORCPT ); Thu, 6 Jul 2017 11:07:01 -0400 Date: Fri, 7 Jul 2017 01:06:46 +1000 From: Nicholas Piggin To: "Gautham R. Shenoy" Cc: Michael Ellerman , Michael Neuling , Vaidyanathan Srinivasan , Shilpasri G Bhat , "Rafael J. Wysocki" , Akshay Adiga , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org Subject: Re: [PATCH 3/5] powernv:idle: Define idle init function for power8 Message-ID: <20170707010646.0157d251@roar.ozlabs.ibm.com> In-Reply-To: <1499272696-28751-4-git-send-email-ego@linux.vnet.ibm.com> References: <1499272696-28751-1-git-send-email-ego@linux.vnet.ibm.com> <1499272696-28751-4-git-send-email-ego@linux.vnet.ibm.com> Organization: IBM X-Mailer: Claws Mail 3.14.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3233 Lines: 97 On Wed, 5 Jul 2017 22:08:14 +0530 "Gautham R. Shenoy" wrote: > From: "Gautham R. Shenoy" > > In this patch we define a new function named pnv_power8_idle_init(). > > We move the following code from pnv_init_idle_states() into this newly > defined function. > a) That patches out pnv_fastsleep_workaround_at_entry/exit when > no states with OPAL_PM_SLEEP_ENABLED_ER1 are present. > b) Creating a sysfs control to choose how the workaround has to be > applied when a OPAL_PM_SLEEP_ENABLED_ER1 state is present. > c) Set ppc_md.power_save to power7_idle when OPAL_PM_NAP_ENABLED is > present. > > With this, all the power8 specific initializations are in one place. > > Signed-off-by: Gautham R. Shenoy > --- > arch/powerpc/platforms/powernv/idle.c | 59 ++++++++++++++++++++++++----------- > 1 file changed, 40 insertions(+), 19 deletions(-) > > diff --git a/arch/powerpc/platforms/powernv/idle.c b/arch/powerpc/platforms/powernv/idle.c > index a5990d9..c400ff9 100644 > --- a/arch/powerpc/platforms/powernv/idle.c > +++ b/arch/powerpc/platforms/powernv/idle.c > @@ -564,6 +564,44 @@ static void __init pnv_power9_idle_init(void) > pnv_first_deep_stop_state); > } > > + > +static void __init pnv_power8_idle_init(void) > +{ > + int i; > + bool has_nap = false; > + bool has_sleep_er1 = false; > + int dt_idle_states = pnv_idle.nr_states; > + > + for (i = 0; i < dt_idle_states; i++) { > + struct pnv_idle_state *state = &pnv_idle.states[i]; > + > + if (state->flags & OPAL_PM_NAP_ENABLED) > + has_nap = true; > + if (state->flags & OPAL_PM_SLEEP_ENABLED_ER1) > + has_sleep_er1 = true; > + } > + > + if (!has_sleep_er1) { > + patch_instruction( > + (unsigned int *)pnv_fastsleep_workaround_at_entry, > + PPC_INST_NOP); > + patch_instruction( > + (unsigned int *)pnv_fastsleep_workaround_at_exit, > + PPC_INST_NOP); > + } else { > + /* > + * OPAL_PM_SLEEP_ENABLED_ER1 is set. It indicates that > + * workaround is needed to use fastsleep. Provide sysfs > + * control to choose how this workaround has to be applied. > + */ > + device_create_file(cpu_subsys.dev_root, > + &dev_attr_fastsleep_workaround_applyonce); > + } > + > + if (has_nap) > + ppc_md.power_save = power7_idle; > +} > + > /* > * Returns 0 if prop1_len == prop2_len. Else returns -1 > */ > @@ -837,6 +875,8 @@ static int __init pnv_probe_idle_states(void) > > if (cpu_has_feature(CPU_FTR_ARCH_300)) > pnv_power9_idle_init(); > + else > + pnv_power8_idle_init(); > > for (i = 0; i < dt_idle_states; i++) { > if (!pnv_idle.states[i].valid) > @@ -858,22 +898,6 @@ static int __init pnv_init_idle_states(void) > if (pnv_probe_idle_states()) > goto out; > > - if (!(supported_cpuidle_states & OPAL_PM_SLEEP_ENABLED_ER1)) { > - patch_instruction( > - (unsigned int *)pnv_fastsleep_workaround_at_entry, > - PPC_INST_NOP); > - patch_instruction( > - (unsigned int *)pnv_fastsleep_workaround_at_exit, > - PPC_INST_NOP); So previously this would run on POWER9 and patch out those branches. But POWER9 never runs that code, so no problem. Good cleanup. Reviewed-by: Nicholas Piggin