| Message ID | 1499272696-28751-4-git-send-email-ego@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On Wed, 5 Jul 2017 22:08:14 +0530 "Gautham R. Shenoy" <ego@linux.vnet.ibm.com> wrote: > From: "Gautham R. Shenoy" <ego@linux.vnet.ibm.com> > > 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 <ego@linux.vnet.ibm.com> > --- > 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 <npiggin@gmail.com>
Hi Nicholas, On Fri, Jul 07, 2017 at 01:06:46AM +1000, Nicholas Piggin wrote: > On Wed, 5 Jul 2017 22:08:14 +0530 > "Gautham R. Shenoy" <ego@linux.vnet.ibm.com> wrote: > > > From: "Gautham R. Shenoy" <ego@linux.vnet.ibm.com> > > > > 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 <ego@linux.vnet.ibm.com> > > --- > > 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. And that's what I thought, but on checking the assembly code, I found that pnv_fastsleep_workaround_at_exit is executed on POWER9. Will fix this! > > Reviewed-by: Nicholas Piggin <npiggin@gmail.com> > -- Thanks and Regards gautham.
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); - } 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); - } pnv_alloc_idle_core_states(); @@ -899,9 +923,6 @@ static int __init pnv_init_idle_states(void) } } - if (supported_cpuidle_states & OPAL_PM_NAP_ENABLED) - ppc_md.power_save = power7_idle; - out: return 0; }