| Message ID | 20210513132051.31465-1-ggherdovich@suse.cz (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | [v2] cpufreq: intel_pstate: Add Icelake servers support in no-HWP mode | expand |
Hi All, Can I on-board to this patch or do you want me to submit another? I want to add COMETLAKE (tested), as below: ... Doug On Thu, May 13, 2021 at 6:21 AM Giovanni Gherdovich <ggherdovich@suse.cz> wrote: > > Users may disable HWP in firmware, in which case intel_pstate wouldn't load > unless the CPU model is explicitly supported. > > Add ICELAKE_X to the list of CPUs that can register intel_pstate while not > advertising the HWP capability. Without this change, an ICELAKE_X in no-HWP > mode could only use the acpi_cpufreq frequency scaling driver. > > See also commit d8de7a44e11f ("cpufreq: intel_pstate: Add Skylake servers > support"). > > Signed-off-by: Giovanni Gherdovich <ggherdovich@suse.cz> > --- > This replaces https://lore.kernel.org/lkml/20210513075930.22657-1-ggherdovich@suse.cz > > drivers/cpufreq/intel_pstate.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c > index f0401064d7aa..28c9733e0dce 100644 > --- a/drivers/cpufreq/intel_pstate.c > +++ b/drivers/cpufreq/intel_pstate.c > @@ -2087,6 +2087,7 @@ static const struct x86_cpu_id intel_pstate_cpu_ids[] = { > X86_MATCH(ATOM_GOLDMONT, core_funcs), > X86_MATCH(ATOM_GOLDMONT_PLUS, core_funcs), > X86_MATCH(SKYLAKE_X, core_funcs), > + X86_MATCH(ICELAKE_X, core_funcs), + X86_MATCH(COMETLAKE, core_funcs), > {} > }; > MODULE_DEVICE_TABLE(x86cpu, intel_pstate_cpu_ids); > -- > 2.26.2 >
On Fri, 2021-05-14 at 08:31 -0700, Doug Smythies wrote: > Hi All, > > Can I on-board to this patch or do you want me to submit another? > I want to add COMETLAKE (tested), as below: > > ... Doug Hello Doug! Wait, why you don't want to use HWP? It's such a fantastic technology! :) I'm just teasing you. More seriously: when COMETLAKE is not in that list, can you confirm that if you go into the BIOS config at boot, and disable HWP from there, then intel_pstate does *not* load? Does it say "intel_pstate: CPU model not supported" in the dmesg log? The control may be somewhere around "power mangement" in the BIOS config, and may be called "Enable/disable Intel Speed Shift". I'm asking because I've just checked on two Dell laptops, one Skylake and the other Kabylake, and the menu is there in the BIOS config to disable HWP, but if I disable it... nothing happens. "lscpu" shows all the hwp flags as usual: # lscpu | grep Flags | tr ' ' '\n' | grep hwp hwp hwp_notify hwp_act_window hwp_epp and turbostat gives me: # turbostat -Summary -i 1 : 2>&1 | grep MSR_PM_ENABLE cpu0: MSR_PM_ENABLE: 0x00000001 (HWP) Which is to say, on the Intel client machines I have, the firmware doesn't seem to be able to hide HWP from the OS. Buggy BIOS? Maybe, the fact of the matter is, I wouldn't need to add, say, KABYLAKE to that list, based on my experience. The other side of the issue is that, from my understanding, the preferred/supported way to disable HWP is to boot with intel_pstate=no_hwp, and that list is a sort of "known exceptions" that people really can't live without (it's mostly server CPUs, and mostly because of unfortunate firmware defaults). Otherwise you'd see the entire intel-family.h file in there. Cheers, Giovanni > > On Thu, May 13, 2021 at 6:21 AM Giovanni Gherdovich <ggherdovich@suse.cz> wrote: > > Users may disable HWP in firmware, in which case intel_pstate wouldn't load > > unless the CPU model is explicitly supported. > > > > Add ICELAKE_X to the list of CPUs that can register intel_pstate while not > > advertising the HWP capability. Without this change, an ICELAKE_X in no-HWP > > mode could only use the acpi_cpufreq frequency scaling driver. > > > > See also commit d8de7a44e11f ("cpufreq: intel_pstate: Add Skylake servers > > support"). > > > > Signed-off-by: Giovanni Gherdovich <ggherdovich@suse.cz> > > --- > > This replaces https://lore.kernel.org/lkml/20210513075930.22657-1-ggherdovich@suse.cz > > > > drivers/cpufreq/intel_pstate.c | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c > > index f0401064d7aa..28c9733e0dce 100644 > > --- a/drivers/cpufreq/intel_pstate.c > > +++ b/drivers/cpufreq/intel_pstate.c > > @@ -2087,6 +2087,7 @@ static const struct x86_cpu_id intel_pstate_cpu_ids[] = { > > X86_MATCH(ATOM_GOLDMONT, core_funcs), > > X86_MATCH(ATOM_GOLDMONT_PLUS, core_funcs), > > X86_MATCH(SKYLAKE_X, core_funcs), > > + X86_MATCH(ICELAKE_X, core_funcs), > + X86_MATCH(COMETLAKE, core_funcs), > > {} > > }; > > MODULE_DEVICE_TABLE(x86cpu, intel_pstate_cpu_ids); > > -- > > 2.26.2 > >
On Fri, May 14, 2021 at 1:33 PM Giovanni Gherdovich <ggherdovich@suse.cz> wrote: > On Fri, 2021-05-14 at 08:31 -0700, Doug Smythies wrote: > > > Can I on-board to this patch or do you want me to submit another? > > I want to add COMETLAKE (tested), as below: > > > > ... Doug > > Hello Doug! Hi Giovanni, Thank you for your reply. > > Wait, why you don't want to use HWP? It's such a fantastic technology! > > :) I'm just teasing you. > > More seriously: > > when COMETLAKE is not in that list, can you confirm that if you go into the > BIOS config at boot, and disable HWP from there, then intel_pstate does *not* load? Yes, already tested before my original reply. > Does it say "intel_pstate: CPU model not supported" in the dmesg log? That I did not check, but if I boot now with an unmodified kernel 5.13-rc1 (i.e. without this patch): [ 0.369323] intel_pstate: CPU model not supported > The control may be somewhere around "power mangement" in the BIOS config, and > may be called "Enable/disable Intel Speed Shift". Yes. > I'm asking because I've just checked on two Dell laptops, one Skylake and the > other Kabylake, and the menu is there in the BIOS config to disable HWP, > but if I disable it... nothing happens. "lscpu" shows all the hwp flags as usual: Motherboard here is ASUS PRIME Z490-A. CPU: Intel(R) Core(TM) i5-10600K CPU @ 4.10GHz > # lscpu | grep Flags | tr ' ' '\n' | grep hwp > hwp > hwp_notify > hwp_act_window > hwp_epp Here, for some reason I have to do it this way (sudo) or your command doesn't work properly. Results herein confirmed by looking at the "Flags" output manually without filtering: intel_speed_shift = Disabled in BIOS: doug@s19:~$ sudo lscpu | tr ' ' '\n' | grep hwp doug@s19:~$ intel_speed_shift = Auto in BIOS $ sudo lscpu | tr ' ' '\n' | grep hwp hwp hwp_notify hwp_act_window hwp_epp > and turbostat gives me: > > # turbostat -Summary -i 1 : 2>&1 | grep MSR_PM_ENABLE > cpu0: MSR_PM_ENABLE: 0x00000001 (HWP) Here: intel_speed_shift = Disabled in BIOS: root@s19:/home/doug# /home/doug/temp-k-git/linux/tools/power/x86/turbostat/turbostat -Summary -i 1 : 2>&1 | grep MSR_PM_ENABLE root@s19:/home/doug# intel_speed_shift = Auto in BIOS (the default setting) root@s19:/home/doug# /home/doug/temp-k-git/linux/tools/power/x86/turbostat/turbostat -Summary -i 1 : 2>&1 | grep MSR_PM_ENABLE cpu0: MSR_PM_ENABLE: 0x00000001 (HWP) or with "intel_pstate=no_hwp" root@s19:/home/doug# /home/doug/temp-k-git/linux/tools/power/x86/turbostat/turbostat -Summary -i 1 : 2>&1 | grep MSR_PM_ENABLE cpu0: MSR_PM_ENABLE: 0x00000000 (No-HWP) > Which is to say, on the Intel client machines I have, the firmware doesn't > seem to be able to hide HWP from the OS. Buggy BIOS? Maybe, the fact of the > matter is, I wouldn't need to add, say, KABYLAKE to that list, based on my > experience. My experience (hardware) differs from yours with respect to this. > The other side of the issue is that, from my understanding, the > preferred/supported way to disable HWP is to boot with intel_pstate=no_hwp, > and that list is a sort of "known exceptions" that people really can't live > without (it's mostly server CPUs, and mostly because of unfortunate firmware > defaults). Otherwise you'd see the entire intel-family.h file in there. I'm not sure how to respond here. Yes, I'd expect to see a big list here, and in the recently added TCC Offset thermal stuff and in the recently added turbostat patches to deal with a TCC offset. I do not understand doing things partially only. But that is a bigger/broader subject than herein. That said, yes, "intel_pstate=no_hwp" is what I normally do. And my BIOS normally has "Intel Speed Shift = AUTO", which is the default. ... deleted the rest ... ... Doug
On Fri, 2021-05-14 at 22:33 +0200, Giovanni Gherdovich wrote: > On Fri, 2021-05-14 at 08:31 -0700, Doug Smythies wrote: > > Hi All, > > > > Can I on-board to this patch or do you want me to submit another? > > I want to add COMETLAKE (tested), as below: > > > > ... Doug > > Hello Doug! > > Wait, why you don't want to use HWP? It's such a fantastic > technology! > > :) I'm just teasing you. > > More seriously: > > when COMETLAKE is not in that list, can you confirm that if you go > into the > BIOS config at boot, and disable HWP from there, then intel_pstate > does *not* load? > > Does it say "intel_pstate: CPU model not supported" in the dmesg log? > > The control may be somewhere around "power mangement" in the BIOS > config, and > may be called "Enable/disable Intel Speed Shift". > > I'm asking because I've just checked on two Dell laptops, one Skylake > and the > other Kabylake, and the menu is there in the BIOS config to disable > HWP, > but if I disable it... nothing happens. "lscpu" shows all the hwp > flags as usual: > > # lscpu | grep Flags | tr ' ' '\n' | grep hwp > hwp > hwp_notify > hwp_act_window > hwp_epp > > and turbostat gives me: > > # turbostat -Summary -i 1 : 2>&1 | grep MSR_PM_ENABLE > cpu0: MSR_PM_ENABLE: 0x00000001 (HWP) > > Which is to say, on the Intel client machines I have, the firmware > doesn't > seem to be able to hide HWP from the OS. Buggy BIOS? Maybe, the fact > of the > matter is, I wouldn't need to add, say, KABYLAKE to that list, based > on my > experience. When you disable in BIOS on these systems, it just hides HWP control via ACPI CPC table. It doesn't disable HWP CPU feature. Thanks, Srinivas > > The other side of the issue is that, from my understanding, the > preferred/supported way to disable HWP is to boot with > intel_pstate=no_hwp, > and that list is a sort of "known exceptions" that people really > can't live > without (it's mostly server CPUs, and mostly because of unfortunate > firmware > defaults). Otherwise you'd see the entire intel-family.h file in > there. > > > Cheers, > Giovanni > > > > > On Thu, May 13, 2021 at 6:21 AM Giovanni Gherdovich < > > ggherdovich@suse.cz> wrote: > > > Users may disable HWP in firmware, in which case intel_pstate > > > wouldn't load > > > unless the CPU model is explicitly supported. > > > > > > Add ICELAKE_X to the list of CPUs that can register intel_pstate > > > while not > > > advertising the HWP capability. Without this change, an ICELAKE_X > > > in no-HWP > > > mode could only use the acpi_cpufreq frequency scaling driver. > > > > > > See also commit d8de7a44e11f ("cpufreq: intel_pstate: Add Skylake > > > servers > > > support"). > > > > > > Signed-off-by: Giovanni Gherdovich <ggherdovich@suse.cz> > > > --- > > > This replaces > > > https://lore.kernel.org/lkml/20210513075930.22657-1-ggherdovich@suse.cz > > > > > > drivers/cpufreq/intel_pstate.c | 1 + > > > 1 file changed, 1 insertion(+) > > > > > > diff --git a/drivers/cpufreq/intel_pstate.c > > > b/drivers/cpufreq/intel_pstate.c > > > index f0401064d7aa..28c9733e0dce 100644 > > > --- a/drivers/cpufreq/intel_pstate.c > > > +++ b/drivers/cpufreq/intel_pstate.c > > > @@ -2087,6 +2087,7 @@ static const struct x86_cpu_id > > > intel_pstate_cpu_ids[] = { > > > X86_MATCH(ATOM_GOLDMONT, core_funcs), > > > X86_MATCH(ATOM_GOLDMONT_PLUS, core_funcs), > > > X86_MATCH(SKYLAKE_X, core_funcs), > > > + X86_MATCH(ICELAKE_X, core_funcs), > > + X86_MATCH(COMETLAKE, core_funcs), > > > {} > > > }; > > > MODULE_DEVICE_TABLE(x86cpu, intel_pstate_cpu_ids); > > > -- > > > 2.26.2 > > > >
On Fri, May 14, 2021 at 5:31 PM Doug Smythies <dsmythies@telus.net> wrote: > > Hi All, > > Can I on-board to this patch or do you want me to submit another? Please send another one.
On Mon, 2021-05-17 at 17:26 +0200, Rafael J. Wysocki wrote: > On Fri, May 14, 2021 at 5:31 PM Doug Smythies <dsmythies@telus.net> wrote: > > Hi All, > > > > Can I on-board to this patch or do you want me to submit another? > > Please send another one. Hello Rafael, Doug, I can resend a series with two patches, one adding ICELAKE_X and the second adding COMETLAKE to the intel_pstate_cpu_ids array. I'll prepare it. Giovanni
On Tue, May 18, 2021 at 4:33 AM Giovanni Gherdovich <ggherdovich@suse.cz> wrote: > On Mon, 2021-05-17 at 17:26 +0200, Rafael J. Wysocki wrote: > > On Fri, May 14, 2021 at 5:31 PM Doug Smythies <dsmythies@telus.net> wrote: > > > Hi All, > > > > > > Can I on-board to this patch or do you want me to submit another? > > > > Please send another one. > > Hello Rafael, Doug, > > I can resend a series with two patches, one adding ICELAKE_X and the > second adding COMETLAKE to the intel_pstate_cpu_ids array. > I'll prepare it. That is very nice of you. Thanks. ... Doug
Hi all, Recent ASUS BIOS updates have changed the default system response for this old thread, rendering "intel_pstate=no_hwp" useless. It also raises a question: If BIOS has forced HWP, then how do we prevent the acpi-cpufreq driver from being used? Read on. On Fri, May 14, 2021 at 3:12 PM Doug Smythies <dsmythies@telus.net> wrote: > > On Fri, May 14, 2021 at 1:33 PM Giovanni Gherdovich <ggherdovich@suse.cz> wrote: > > On Fri, 2021-05-14 at 08:31 -0700, Doug Smythies wrote: ... > > > > when COMETLAKE is not in that list, can you confirm that if you go into the > > BIOS config at boot, and disable HWP from there, then intel_pstate does *not* load? > > Yes, already tested before my original reply. > > > Does it say "intel_pstate: CPU model not supported" in the dmesg log? > > That I did not check, but if I boot now with an unmodified kernel > 5.13-rc1 (i.e. without this patch): > > [ 0.369323] intel_pstate: CPU model not supported > > > The control may be somewhere around "power mangement" in the BIOS config, and > > may be called "Enable/disable Intel Speed Shift". > > Yes. > > > I'm asking because I've just checked on two Dell laptops, one Skylake and the > > other Kabylake, and the menu is there in the BIOS config to disable HWP, > > but if I disable it... nothing happens. "lscpu" shows all the hwp flags as usual: > > Motherboard here is ASUS PRIME Z490-A. > CPU: Intel(R) Core(TM) i5-10600K CPU @ 4.10GHz > > > # lscpu | grep Flags | tr ' ' '\n' | grep hwp > > hwp > > hwp_notify > > hwp_act_window > > hwp_epp > > Here, for some reason I have to do it this way (sudo) or your command > doesn't work properly. Results herein confirmed by looking at the > "Flags" output manually without filtering: > > intel_speed_shift = Disabled in BIOS: > > doug@s19:~$ sudo lscpu | tr ' ' '\n' | grep hwp > doug@s19:~$ > > intel_speed_shift = Auto in BIOS > > $ sudo lscpu | tr ' ' '\n' | grep hwp > hwp > hwp_notify > hwp_act_window > hwp_epp > > > and turbostat gives me: > > > > # turbostat -Summary -i 1 : 2>&1 | grep MSR_PM_ENABLE > > cpu0: MSR_PM_ENABLE: 0x00000001 (HWP) > > Here: > > intel_speed_shift = Disabled in BIOS: > > root@s19:/home/doug# > /home/doug/temp-k-git/linux/tools/power/x86/turbostat/turbostat > -Summary -i 1 : 2>&1 | grep MSR_PM_ENABLE > root@s19:/home/doug# > > intel_speed_shift = Auto in BIOS (the default setting) > > root@s19:/home/doug# > /home/doug/temp-k-git/linux/tools/power/x86/turbostat/turbostat > -Summary -i 1 : 2>&1 | grep MSR_PM_ENABLE > cpu0: MSR_PM_ENABLE: 0x00000001 (HWP) > > or with "intel_pstate=no_hwp" > > root@s19:/home/doug# > /home/doug/temp-k-git/linux/tools/power/x86/turbostat/turbostat > -Summary -i 1 : 2>&1 | grep MSR_PM_ENABLE > cpu0: MSR_PM_ENABLE: 0x00000000 (No-HWP) > > > Which is to say, on the Intel client machines I have, the firmware doesn't > > seem to be able to hide HWP from the OS. Buggy BIOS? Maybe, the fact of the > > matter is, I wouldn't need to add, say, KABYLAKE to that list, based on my > > experience. > > My experience (hardware) differs from yours with respect to this. > > > The other side of the issue is that, from my understanding, the > > preferred/supported way to disable HWP is to boot with intel_pstate=no_hwp, Previous correspondence was with BIOS version 1003. There have been 3 BIOS releases since then (at least that I know of), 2103, 2201, 2301, and all of them have changed the behaviour of the "Auto" setting for Intel Speed Shift Technology BIOS setting, forcing it on upon transfer of control to the OS. Where with "intel_pstate=no_hwp" one used to get 0 for MSR_PM_ENABLE (0x770) they now get 1. That was for my ASUS Z490-P Motherboard. For my ASUS Z390-A Motherboard (actually a windows 10 computer now), with an older BIOS, things still work properly for "intel_pstate=no_hwp", and while there is a newer BIOS, I will not install it as it is also not possible to rollback. I have had an escalation in progress with ASUS about this for about a month, and while they have been responsive we have communications/language issues and have yet to even agree that there is an issue. I have been working with this incomplete patch: diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index bb4549959b11..7dcc51ee56ea 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -3347,17 +3347,27 @@ device_initcall(intel_pstate_init); static int __init intel_pstate_setup(char *str) { + /* The following needs to be conditional on CPUID with EAX 6 */ + /* CPUID.06H:EAX[bit 7], which I do not know how to do. */ + /* Avoid doing checking and printing multiple times, */ + /* which I do not know why it does. */ + if(!force_load){ + if(intel_pstate_hwp_is_enabled()){ + pr_info("HWP enabled by BIOS\n"); + force_load = 1; + } + } if (!str) return -EINVAL; - if (!strcmp(str, "disable")) + if (!strcmp(str, "disable") && !force_load) no_load = 1; - else if (!strcmp(str, "active")) + if (!strcmp(str, "active") && !no_load) default_driver = &intel_pstate; else if (!strcmp(str, "passive")) default_driver = &intel_cpufreq; - if (!strcmp(str, "no_hwp")) { + if (!strcmp(str, "no_hwp") && !force_load) { pr_info("HWP disabled\n"); no_hwp = 1; } Which has troubles when HWP has been disabled by BIOS, but otherwise works well. HWP Disabled by BIOS: doug@s19:~$ sudo dmesg | grep intel_pstate [sudo] password for doug: [ 0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-5.14.0-ipstate4 root=UUID=0ac356c1-caa9-4c2e-8229-4408bd998dbd ro ipv6.disable=1 consoleblank=314 intel_pstate=active intel_pstate=no_hwp msr.allow_writes=on cpuidle.governor=teo [ 0.000000] intel_pstate_setup+0x24/0x151 [ 0.000000] intel_pstate_setup+0x24/0x151 [ 0.000000] intel_pstate: HWP disabled [ 0.051278] Kernel command line: BOOT_IMAGE=/boot/vmlinuz-5.14.0-ipstate4 root=UUID=0ac356c1-caa9-4c2e-8229-4408bd998dbd ro ipv6.disable=1 consoleblank=314 intel_pstate=active intel_pstate=no_hwp msr.allow_writes=on cpuidle.governor=teo [ 0.393236] intel_pstate: Intel P-state driver initializing HWP force enabled by BIOS, which is the only other option with the newer BIOS: doug@s19:~$ sudo dmesg | grep intel_pstate [sudo] password for doug: [ 0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-5.14.0-ipstate4 root=UUID=0ac356c1-caa9-4c2e-8229-4408bd998dbd ro ipv6.disable=1 consoleblank=314 intel_pstate=active intel_pstate=no_hwp msr.allow_writes=on cpuidle.governor=teo [ 0.000000] intel_pstate: HWP enabled by BIOS [ 0.049205] Kernel command line: BOOT_IMAGE=/boot/vmlinuz-5.14.0-ipstate4 root=UUID=0ac356c1-caa9-4c2e-8229-4408bd998dbd ro ipv6.disable=1 consoleblank=314 intel_pstate=active intel_pstate=no_hwp msr.allow_writes=on cpuidle.governor=teo [ 0.370662] intel_pstate: Intel P-state driver initializing [ 0.371590] intel_pstate: HWP enabled HWP forced by BIOS, disable intel_pstate: doug@s19:~$ sudo dmesg | grep intel_pstate [ 0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-5.14.0-ipstate4 root=UUID=0ac356c1-caa9-4c2e-8229-4408bd998dbd ro ipv6.disable=1 consoleblank=300 intel_pstate=disable msr.allow_writes=on cpuidle.governor=teo [ 0.000000] intel_pstate: HWP enabled by BIOS [ 0.049133] Kernel command line: BOOT_IMAGE=/boot/vmlinuz-5.14.0-ipstate4 root=UUID=0ac356c1-caa9-4c2e-8229-4408bd998dbd ro ipv6.disable=1 consoleblank=300 intel_pstate=disable msr.allow_writes=on cpuidle.governor=teo [ 0.370519] intel_pstate: Intel P-state driver initializing [ 0.371451] intel_pstate: HWP enabled doug@s19:~$ cat /sys/devices/system/cpu/cpu5/cpufreq/scaling_driver intel_pstate HWP forced by BIOS, disable intel_pstate:, unpatched kernel 5.14: doug@s19:~$ sudo dmesg | grep intel_pstate [ 0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-5.14.0-stock root=UUID=0ac356c1-caa9-4c2e-8229-4408bd998dbd ro ipv6.disable=1 consoleblank=300 intel_pstate=disable msr.allow_writes=on cpuidle.governor=teo [ 0.049108] Kernel command line: BOOT_IMAGE=/boot/vmlinuz-5.14.0-stock root=UUID=0ac356c1-caa9-4c2e-8229-4408bd998dbd ro ipv6.disable=1 consoleblank=300 intel_pstate=disable msr.allow_writes=on cpuidle.governor=teo doug@s19:~$ cat /sys/devices/system/cpu/cpu5/cpufreq/scaling_driver acpi-cpufreq doug@s19:~$ sudo rdmsr 0x770 1 Observe the driver ended up as acpi-cpufreq, but with HWP enabled. ... Doug
Hi Doug, On Tue, 2021-09-07 at 08:45 -0700, Doug Smythies wrote: > Hi all, > > Recent ASUS BIOS updates have changed the default system > response for this old thread, rendering "intel_pstate=no_hwp" > useless. > > It also raises a question: If BIOS has forced HWP, then how do we > prevent the acpi-cpufreq driver from being used? Read on. Does BIOS has option to enable Intel speed shift with no legacy support? Then this option will not populate ACPI _PSS table. > > On Fri, May 14, 2021 at 3:12 PM Doug Smythies <dsmythies@telus.net> > wrote: > > > > On Fri, May 14, 2021 at 1:33 PM Giovanni Gherdovich < > > ggherdovich@suse.cz> wrote: > > > On Fri, 2021-05-14 at 08:31 -0700, Doug Smythies wrote: > ... > > > > > > when COMETLAKE is not in that list, can you confirm that if you > > > go into the > > > BIOS config at boot, and disable HWP from there, then > > > intel_pstate does *not* load? > > > > Yes, already tested before my original reply. > > > > > Does it say "intel_pstate: CPU model not supported" in the dmesg > > > log? > > > > That I did not check, but if I boot now with an unmodified kernel > > 5.13-rc1 (i.e. without this patch): > > > > [ 0.369323] intel_pstate: CPU model not supported > > > > > The control may be somewhere around "power mangement" in the BIOS > > > config, and > > > may be called "Enable/disable Intel Speed Shift". > > > > Yes. > > > > > I'm asking because I've just checked on two Dell laptops, one > > > Skylake and the > > > other Kabylake, and the menu is there in the BIOS config to > > > disable HWP, > > > but if I disable it... nothing happens. "lscpu" shows all the hwp > > > flags as usual: > > > > Motherboard here is ASUS PRIME Z490-A. > > CPU: Intel(R) Core(TM) i5-10600K CPU @ 4.10GHz > > > > > # lscpu | grep Flags | tr ' ' '\n' | grep hwp > > > hwp > > > hwp_notify > > > hwp_act_window > > > hwp_epp > > > > Here, for some reason I have to do it this way (sudo) or your > > command > > doesn't work properly. Results herein confirmed by looking at the > > "Flags" output manually without filtering: > > > > intel_speed_shift = Disabled in BIOS: > > > > doug@s19:~$ sudo lscpu | tr ' ' '\n' | grep hwp > > doug@s19:~$ > > > > intel_speed_shift = Auto in BIOS > > > > $ sudo lscpu | tr ' ' '\n' | grep hwp > > hwp > > hwp_notify > > hwp_act_window > > hwp_epp > > > > > and turbostat gives me: > > > > > > # turbostat -Summary -i 1 : 2>&1 | grep MSR_PM_ENABLE > > > cpu0: MSR_PM_ENABLE: 0x00000001 (HWP) > > > > Here: > > > > intel_speed_shift = Disabled in BIOS: > > > > root@s19:/home/doug# > > /home/doug/temp-k-git/linux/tools/power/x86/turbostat/turbostat > > -Summary -i 1 : 2>&1 | grep MSR_PM_ENABLE > > root@s19:/home/doug# > > > > intel_speed_shift = Auto in BIOS (the default setting) > > > > root@s19:/home/doug# > > /home/doug/temp-k-git/linux/tools/power/x86/turbostat/turbostat > > -Summary -i 1 : 2>&1 | grep MSR_PM_ENABLE > > cpu0: MSR_PM_ENABLE: 0x00000001 (HWP) > > > > or with "intel_pstate=no_hwp" > > > > root@s19:/home/doug# > > /home/doug/temp-k-git/linux/tools/power/x86/turbostat/turbostat > > -Summary -i 1 : 2>&1 | grep MSR_PM_ENABLE > > cpu0: MSR_PM_ENABLE: 0x00000000 (No-HWP) > > > > > Which is to say, on the Intel client machines I have, the > > > firmware doesn't > > > seem to be able to hide HWP from the OS. Buggy BIOS? Maybe, the > > > fact of the > > > matter is, I wouldn't need to add, say, KABYLAKE to that list, > > > based on my > > > experience. > > > > My experience (hardware) differs from yours with respect to this. > > > > > The other side of the issue is that, from my understanding, the > > > preferred/supported way to disable HWP is to boot with > > > intel_pstate=no_hwp, > > Previous correspondence was with BIOS version 1003. There have been 3 > BIOS > releases since then (at least that I know of), 2103, 2201, 2301, and > all of them > have changed the behaviour of the "Auto" setting for Intel Speed > Shift > Technology BIOS setting, forcing it on upon transfer of control to > the OS. > > Where with "intel_pstate=no_hwp" one used to get 0 for MSR_PM_ENABLE > (0x770) they now get 1. So they are forcing Out of band OOB mode. Does bit 8 or 18 in MSR 0x1aa is set? Thanks, Srinivas > > That was for my ASUS Z490-P Motherboard. > For my ASUS Z390-A Motherboard (actually a windows 10 computer now), > with an older BIOS, things still work properly for > "intel_pstate=no_hwp", and > while there is a newer BIOS, I will not install it as it is also not > possible to > rollback. > > I have had an escalation in progress with ASUS about this for about a > month, > and while they have been responsive we have communications/language > issues and have yet to even agree that there is an issue. > > I have been working with this incomplete patch: > > diff --git a/drivers/cpufreq/intel_pstate.c > b/drivers/cpufreq/intel_pstate.c > index bb4549959b11..7dcc51ee56ea 100644 > --- a/drivers/cpufreq/intel_pstate.c > +++ b/drivers/cpufreq/intel_pstate.c > @@ -3347,17 +3347,27 @@ device_initcall(intel_pstate_init); > > static int __init intel_pstate_setup(char *str) > { > + /* The following needs to be conditional on CPUID with EAX 6 > */ > + /* CPUID.06H:EAX[bit 7], which I do not know how to do. */ > + /* Avoid doing checking and printing multiple times, */ > + /* which I do not know why it does. */ > + if(!force_load){ > + if(intel_pstate_hwp_is_enabled()){ > + pr_info("HWP enabled by BIOS\n"); > + force_load = 1; > + } > + } > if (!str) > return -EINVAL; > > - if (!strcmp(str, "disable")) > + if (!strcmp(str, "disable") && !force_load) > no_load = 1; > - else if (!strcmp(str, "active")) > + if (!strcmp(str, "active") && !no_load) > default_driver = &intel_pstate; > else if (!strcmp(str, "passive")) > default_driver = &intel_cpufreq; > > - if (!strcmp(str, "no_hwp")) { > + if (!strcmp(str, "no_hwp") && !force_load) { > pr_info("HWP disabled\n"); > no_hwp = 1; > } > > Which has troubles when HWP has been disabled by BIOS, but otherwise > works well. > > HWP Disabled by BIOS: > > doug@s19:~$ sudo dmesg | grep intel_pstate > [sudo] password for doug: > [ 0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-5.14.0-ipstate4 > root=UUID=0ac356c1-caa9-4c2e-8229-4408bd998dbd ro ipv6.disable=1 > consoleblank=314 intel_pstate=active intel_pstate=no_hwp > msr.allow_writes=on cpuidle.governor=teo > [ 0.000000] intel_pstate_setup+0x24/0x151 > [ 0.000000] intel_pstate_setup+0x24/0x151 > [ 0.000000] intel_pstate: HWP disabled > [ 0.051278] Kernel command line: > BOOT_IMAGE=/boot/vmlinuz-5.14.0-ipstate4 > root=UUID=0ac356c1-caa9-4c2e-8229-4408bd998dbd ro ipv6.disable=1 > consoleblank=314 intel_pstate=active intel_pstate=no_hwp > msr.allow_writes=on cpuidle.governor=teo > [ 0.393236] intel_pstate: Intel P-state driver initializing > > HWP force enabled by BIOS, which is the only other option with the > newer BIOS: > > doug@s19:~$ sudo dmesg | grep intel_pstate > [sudo] password for doug: > [ 0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-5.14.0-ipstate4 > root=UUID=0ac356c1-caa9-4c2e-8229-4408bd998dbd ro ipv6.disable=1 > consoleblank=314 intel_pstate=active intel_pstate=no_hwp > msr.allow_writes=on cpuidle.governor=teo > [ 0.000000] intel_pstate: HWP enabled by BIOS > [ 0.049205] Kernel command line: > BOOT_IMAGE=/boot/vmlinuz-5.14.0-ipstate4 > root=UUID=0ac356c1-caa9-4c2e-8229-4408bd998dbd ro ipv6.disable=1 > consoleblank=314 intel_pstate=active intel_pstate=no_hwp > msr.allow_writes=on cpuidle.governor=teo > [ 0.370662] intel_pstate: Intel P-state driver initializing > [ 0.371590] intel_pstate: HWP enabled > > HWP forced by BIOS, disable intel_pstate: > > doug@s19:~$ sudo dmesg | grep intel_pstate > [ 0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-5.14.0-ipstate4 > root=UUID=0ac356c1-caa9-4c2e-8229-4408bd998dbd ro ipv6.disable=1 > consoleblank=300 intel_pstate=disable msr.allow_writes=on > cpuidle.governor=teo > [ 0.000000] intel_pstate: HWP enabled by BIOS > [ 0.049133] Kernel command line: > BOOT_IMAGE=/boot/vmlinuz-5.14.0-ipstate4 > root=UUID=0ac356c1-caa9-4c2e-8229-4408bd998dbd ro ipv6.disable=1 > consoleblank=300 intel_pstate=disable msr.allow_writes=on > cpuidle.governor=teo > [ 0.370519] intel_pstate: Intel P-state driver initializing > [ 0.371451] intel_pstate: HWP enabled > doug@s19:~$ cat /sys/devices/system/cpu/cpu5/cpufreq/scaling_driver > intel_pstate > > HWP forced by BIOS, disable intel_pstate:, unpatched kernel 5.14: > > doug@s19:~$ sudo dmesg | grep intel_pstate > [ 0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-5.14.0-stock > root=UUID=0ac356c1-caa9-4c2e-8229-4408bd998dbd ro ipv6.disable=1 > consoleblank=300 intel_pstate=disable msr.allow_writes=on > cpuidle.governor=teo > [ 0.049108] Kernel command line: > BOOT_IMAGE=/boot/vmlinuz-5.14.0-stock > root=UUID=0ac356c1-caa9-4c2e-8229-4408bd998dbd ro ipv6.disable=1 > consoleblank=300 intel_pstate=disable msr.allow_writes=on > cpuidle.governor=teo > doug@s19:~$ cat /sys/devices/system/cpu/cpu5/cpufreq/scaling_driver > acpi-cpufreq > doug@s19:~$ sudo rdmsr 0x770 > 1 > > Observe the driver ended up as acpi-cpufreq, but with HWP enabled. > > ... Doug
Hi Srinivas, Thank you for your reply. On Tue, Sep 7, 2021 at 9:01 AM Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> wrote: > On Tue, 2021-09-07 at 08:45 -0700, Doug Smythies wrote: >> > > Recent ASUS BIOS updates have changed the default system > > response for this old thread, rendering "intel_pstate=no_hwp" > > useless. > > > > It also raises a question: If BIOS has forced HWP, then how do we > > prevent the acpi-cpufreq driver from being used? Read on. > > Does BIOS has option to enable Intel speed shift with no legacy > support? > Then this option will not populate ACPI _PSS table. The option is there no matter what. I have tried every variation of legacy or no legacy that I can find. Currently: Current boot mode: UEFI Firmware mode SecureBoot: disabled > > > > > On Fri, May 14, 2021 at 3:12 PM Doug Smythies <dsmythies@telus.net> > > wrote: > > > > > > On Fri, May 14, 2021 at 1:33 PM Giovanni Gherdovich < > > > ggherdovich@suse.cz> wrote: > > > > On Fri, 2021-05-14 at 08:31 -0700, Doug Smythies wrote: > > ... > > > > ... > > Previous correspondence was with BIOS version 1003. There have been 3 > > BIOS > > releases since then (at least that I know of), 2103, 2201, 2301, and > > all of them > > have changed the behaviour of the "Auto" setting for Intel Speed > > Shift > > Technology BIOS setting, forcing it on upon transfer of control to > > the OS. > > > > Where with "intel_pstate=no_hwp" one used to get 0 for MSR_PM_ENABLE > > (0x770) they now get 1. > > So they are forcing Out of band OOB mode. > Does bit 8 or 18 in MSR 0x1aa is set? No. Here is the output from my msr reader/decoder program. Kernel 5.14 (unpatched). intel_pstate=disable BIOS setting "Auto" for Intel Speed Shift, Driver: acpi-cpufreq doug@s19:~$ sudo c/msr-decoder How many CPUs?: 12 8.) 0x198: IA32_PERF_STATUS : CPU 0-11 : 45 : 45 : 45 : 45 : 45 : 45 : 45 : 45 : 45 : 45 : 45 : 45 : B.) 0x770: IA32_PM_ENABLE: 1 : HWP enable 1.) 0x19C: IA32_THERM_STATUS: 88450000 2.) 0x1AA: MSR_MISC_PWR_MGMT: 401CC0 EIST enabled Coordination enabled OOB Bit 8 reset OOB Bit 18 reset 3.) 0x1B1: IA32_PACKAGE_THERM_STATUS: 88410000 4.) 0x64F: MSR_CORE_PERF_LIMIT_REASONS: 0 A.) 0x1FC: MSR_POWER_CTL: 3C005D : C1E disable : EEO disable : RHO disable 5.) 0x771: IA32_HWP_CAPABILITIES (performance): 10B2930 : high 48 : guaranteed 41 : efficient 11 : lowest 1 6.) 0x774: IA32_HWP_REQUEST: CPU 0-11 : raw: 80003001 : 80003001 : 80003001 : 80003001 : 80003001 : 80003001 : 80003001 : 80003001 : 80003001 : 80003001 : 80003001 : 80003001 : min: 1 : 1 : 1 : 1 : 1 : 1 : 1 : 1 : 1 : 1 : 1 : 1 : max: 48 : 48 : 48 : 48 : 48 : 48 : 48 : 48 : 48 : 48 : 48 : 48 : des: 0 : 0 : 0 : 0 : 0 : 0 : 0 : 0 : 0 : 0 : 0 : 0 : epp: 128 : 128 : 128 : 128 : 128 : 128 : 128 : 128 : 128 : 128 : 128 : 128 : act: 0 : 0 : 0 : 0 : 0 : 0 : 0 : 0 : 0 : 0 : 0 : 0 : 7.) 0x777: IA32_HWP_STATUS: 0 : high 0 : guaranteed 0 : efficient 0 : lowest 0 ... ... Doug
On Tue, 2021-09-07 at 13:16 -0700, Doug Smythies wrote: > Hi Srinivas, Thank you for your reply. > > On Tue, Sep 7, 2021 at 9:01 AM Srinivas Pandruvada > <srinivas.pandruvada@linux.intel.com> wrote: > > On Tue, 2021-09-07 at 08:45 -0700, Doug Smythies wrote: > > > > > > Recent ASUS BIOS updates have changed the default system > > > response for this old thread, rendering "intel_pstate=no_hwp" > > > useless. > > > > > > It also raises a question: If BIOS has forced HWP, then how do we > > > prevent the acpi-cpufreq driver from being used? Read on. > > > > Does BIOS has option to enable Intel speed shift with no legacy > > support? > > Then this option will not populate ACPI _PSS table. > > The option is there no matter what. > I have tried every variation of legacy or no legacy that > I can find. Currently: > Current boot mode: UEFI Firmware mode > SecureBoot: disabled > > > > > > > > > On Fri, May 14, 2021 at 3:12 PM Doug Smythies < > > > dsmythies@telus.net> > > > wrote: > > > > > > > > On Fri, May 14, 2021 at 1:33 PM Giovanni Gherdovich < > > > > ggherdovich@suse.cz> wrote: > > > > > On Fri, 2021-05-14 at 08:31 -0700, Doug Smythies wrote: > > > ... > > > > > > ... > > > Previous correspondence was with BIOS version 1003. There have > > > been 3 > > > BIOS > > > releases since then (at least that I know of), 2103, 2201, 2301, > > > and > > > all of them > > > have changed the behaviour of the "Auto" setting for Intel Speed > > > Shift > > > Technology BIOS setting, forcing it on upon transfer of control > > > to > > > the OS. > > > > > > Where with "intel_pstate=no_hwp" one used to get 0 for > > > MSR_PM_ENABLE > > > (0x770) they now get 1. > > > > So they are forcing Out of band OOB mode. > > Does bit 8 or 18 in MSR 0x1aa is set? > > No. So there is no legacy path. I think you are working with their support. In HWP mode does setting scaling min/max frequency has any impact? Thanks, Srinivas > > Here is the output from my msr reader/decoder program. > Kernel 5.14 (unpatched). > intel_pstate=disable > BIOS setting "Auto" for Intel Speed Shift, > Driver: acpi-cpufreq > > doug@s19:~$ sudo c/msr-decoder > How many CPUs?: 12 > 8.) 0x198: IA32_PERF_STATUS : CPU 0-11 : 45 : 45 : 45 : 45 : > 45 : 45 : 45 : 45 : 45 : 45 : 45 : 45 : > B.) 0x770: IA32_PM_ENABLE: 1 : HWP enable > 1.) 0x19C: IA32_THERM_STATUS: 88450000 > 2.) 0x1AA: MSR_MISC_PWR_MGMT: 401CC0 EIST enabled Coordination > enabled > OOB Bit 8 reset OOB Bit 18 reset > 3.) 0x1B1: IA32_PACKAGE_THERM_STATUS: 88410000 > 4.) 0x64F: MSR_CORE_PERF_LIMIT_REASONS: 0 > A.) 0x1FC: MSR_POWER_CTL: 3C005D : C1E disable : EEO disable : RHO > disable > 5.) 0x771: IA32_HWP_CAPABILITIES (performance): 10B2930 : high 48 : > guaranteed 41 : efficient 11 : lowest 1 > 6.) 0x774: IA32_HWP_REQUEST: CPU 0-11 : > raw: 80003001 : 80003001 : 80003001 : 80003001 : 80003001 : > 80003001 : 80003001 : 80003001 : 80003001 : 80003001 : 80003001 : > 80003001 : > min: 1 : 1 : 1 : 1 : 1 : > 1 : 1 : 1 : 1 : 1 : 1 : 1 : > max: 48 : 48 : 48 : 48 : 48 : > 48 : 48 : 48 : 48 : 48 : 48 : 48 > : > des: 0 : 0 : 0 : 0 : 0 : > 0 : 0 : 0 : 0 : 0 : 0 : 0 : > epp: 128 : 128 : 128 : 128 : 128 : > 128 : 128 : 128 : 128 : 128 : 128 : 128 > : > act: 0 : 0 : 0 : 0 : 0 : > 0 : 0 : 0 : 0 : 0 : 0 : 0 : > 7.) 0x777: IA32_HWP_STATUS: 0 : high 0 : guaranteed 0 : efficient 0 : > lowest 0 > > ... > > ... Doug
On Tue, Sep 7, 2021 at 7:04 PM Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> wrote: > > On Tue, 2021-09-07 at 13:16 -0700, Doug Smythies wrote: > > Hi Srinivas, Thank you for your reply. > > > > On Tue, Sep 7, 2021 at 9:01 AM Srinivas Pandruvada > > <srinivas.pandruvada@linux.intel.com> wrote: > > > On Tue, 2021-09-07 at 08:45 -0700, Doug Smythies wrote: > > > > > > > > Recent ASUS BIOS updates have changed the default system > > > > response for this old thread, rendering "intel_pstate=no_hwp" > > > > useless. > > > > > > > > It also raises a question: If BIOS has forced HWP, then how do we > > > > prevent the acpi-cpufreq driver from being used? Read on. > > > > > > Does BIOS has option to enable Intel speed shift with no legacy > > > support? > > > Then this option will not populate ACPI _PSS table. > > > > The option is there no matter what. > > I have tried every variation of legacy or no legacy that > > I can find. Currently: > > Current boot mode: UEFI Firmware mode > > SecureBoot: disabled > > > > > > > > > > > > > On Fri, May 14, 2021 at 3:12 PM Doug Smythies < > > > > dsmythies@telus.net> > > > > wrote: > > > > > > > > > > On Fri, May 14, 2021 at 1:33 PM Giovanni Gherdovich < > > > > > ggherdovich@suse.cz> wrote: > > > > > > On Fri, 2021-05-14 at 08:31 -0700, Doug Smythies wrote: > > > > ... > > > > > > > > ... > > > > Previous correspondence was with BIOS version 1003. There have > > > > been 3 > > > > BIOS > > > > releases since then (at least that I know of), 2103, 2201, 2301, > > > > and > > > > all of them > > > > have changed the behaviour of the "Auto" setting for Intel Speed > > > > Shift > > > > Technology BIOS setting, forcing it on upon transfer of control > > > > to > > > > the OS. > > > > > > > > Where with "intel_pstate=no_hwp" one used to get 0 for > > > > MSR_PM_ENABLE > > > > (0x770) they now get 1. > > > > > > So they are forcing Out of band OOB mode. > > > Does bit 8 or 18 in MSR 0x1aa is set? > > > > No. > > So there is no legacy path. I think you are working with their support. Yes, for almost a month now, with very little to show for it. We'll see what happens. I did get a message this afternoon: "Our GTSD is debugging the issue,. When they have the result, they will directly update you." > In HWP mode does setting scaling min/max frequency has any impact? No. I wouldn't have expected it to, as the system is confused as to who is in charge. The acpi-cpufreq driver thinks it is in charge, but HWP thinks it is. The intel_pstate driver works fine. ... Doug > > Thanks, > Srinivas > > > > > Here is the output from my msr reader/decoder program. > > Kernel 5.14 (unpatched). > > intel_pstate=disable > > BIOS setting "Auto" for Intel Speed Shift, > > Driver: acpi-cpufreq > > > > doug@s19:~$ sudo c/msr-decoder > > How many CPUs?: 12 > > 8.) 0x198: IA32_PERF_STATUS : CPU 0-11 : 45 : 45 : 45 : 45 : > > 45 : 45 : 45 : 45 : 45 : 45 : 45 : 45 : > > B.) 0x770: IA32_PM_ENABLE: 1 : HWP enable > > 1.) 0x19C: IA32_THERM_STATUS: 88450000 > > 2.) 0x1AA: MSR_MISC_PWR_MGMT: 401CC0 EIST enabled Coordination > > enabled > > OOB Bit 8 reset OOB Bit 18 reset > > 3.) 0x1B1: IA32_PACKAGE_THERM_STATUS: 88410000 > > 4.) 0x64F: MSR_CORE_PERF_LIMIT_REASONS: 0 > > A.) 0x1FC: MSR_POWER_CTL: 3C005D : C1E disable : EEO disable : RHO > > disable > > 5.) 0x771: IA32_HWP_CAPABILITIES (performance): 10B2930 : high 48 : > > guaranteed 41 : efficient 11 : lowest 1 > > 6.) 0x774: IA32_HWP_REQUEST: CPU 0-11 : > > raw: 80003001 : 80003001 : 80003001 : 80003001 : 80003001 : > > 80003001 : 80003001 : 80003001 : 80003001 : 80003001 : 80003001 : > > 80003001 : > > min: 1 : 1 : 1 : 1 : 1 : > > 1 : 1 : 1 : 1 : 1 : 1 : 1 : > > max: 48 : 48 : 48 : 48 : 48 : > > 48 : 48 : 48 : 48 : 48 : 48 : 48 > > : > > des: 0 : 0 : 0 : 0 : 0 : > > 0 : 0 : 0 : 0 : 0 : 0 : 0 : > > epp: 128 : 128 : 128 : 128 : 128 : > > 128 : 128 : 128 : 128 : 128 : 128 : 128 > > : > > act: 0 : 0 : 0 : 0 : 0 : > > 0 : 0 : 0 : 0 : 0 : 0 : 0 : > > 7.) 0x777: IA32_HWP_STATUS: 0 : high 0 : guaranteed 0 : efficient 0 : > > lowest 0 > > > > ... > > > > ... Doug > >
On Tue, Sep 7, 2021 at 8:43 PM Doug Smythies <dsmythies@telus.net> wrote: > On Tue, Sep 7, 2021 at 7:04 PM Srinivas Pandruvada > <srinivas.pandruvada@linux.intel.com> wrote: > > On Tue, 2021-09-07 at 13:16 -0700, Doug Smythies wrote: > > > On Tue, Sep 7, 2021 at 9:01 AM Srinivas Pandruvada > > > <srinivas.pandruvada@linux.intel.com> wrote: > > > > On Tue, 2021-09-07 at 08:45 -0700, Doug Smythies wrote: > > > > > > > > > > Recent ASUS BIOS updates have changed the default system > > > > > response for this old thread, rendering "intel_pstate=no_hwp" > > > > > useless. > > > > > > > > > > It also raises a question: If BIOS has forced HWP, then how do we > > > > > prevent the acpi-cpufreq driver from being used? Read on. > > > > > > > > Does BIOS has option to enable Intel speed shift with no legacy > > > > support? > > > > Then this option will not populate ACPI _PSS table. > > > > > > The option is there no matter what. > > > I have tried every variation of legacy or no legacy that > > > I can find. Currently: > > > Current boot mode: UEFI Firmware mode > > > SecureBoot: disabled > > > > > > > > > > > > > > > > > On Fri, May 14, 2021 at 3:12 PM Doug Smythies < > > > > > dsmythies@telus.net> > > > > > wrote: > > > > > > > > > > > > On Fri, May 14, 2021 at 1:33 PM Giovanni Gherdovich < > > > > > > ggherdovich@suse.cz> wrote: > > > > > > > On Fri, 2021-05-14 at 08:31 -0700, Doug Smythies wrote: > > > > > ... > > > > > > > > > > ... > > > > > Previous correspondence was with BIOS version 1003. There have > > > > > been 3 BIOS > > > > > releases since then (at least that I know of), 2103, 2201, 2301, > > > > > and all of them have changed the behaviour > > > > > of the "Auto" setting for Intel Speed Shift > > > > > Technology BIOS setting, forcing it on upon transfer of control > > > > > to the OS. > > > > > > > > > > Where with "intel_pstate=no_hwp" one used to get 0 for > > > > > MSR_PM_ENABLE > > > > > (0x770) they now get 1. > > > > > > > > So they are forcing Out of band OOB mode. > > > > Does bit 8 or 18 in MSR 0x1aa is set? > > > > > > No. > > > > So there is no legacy path. I think you are working with their support. > > Yes, for almost a month now, with very little to show for it. > We'll see what happens. I did get a message this afternoon: > > "Our GTSD is debugging the issue,. > When they have the result, they will directly update you." > > > In HWP mode does setting scaling min/max frequency has any impact? > > No. I wouldn't have expected it to, as the system is confused as to who > is in charge. The acpi-cpufreq driver thinks it is in charge, but HWP > thinks it is. > > The intel_pstate driver works fine. Hi Srinivas, I heard back from ASUS, and they now confirm that they did change the behaviour of the "Auto" setting in BIOS version 2103. They say they did it to fix an issue with ITB3.0, which I assume means Intel Turbo Boost 3.0. I'll copy and paste the relevant portion of the email below: " I am in direct contact with the engineers. Here is the result from their test: In BIOS 2103,the “Auto” setting transfers control to the OS with HWP available and enabled. This is side effect to fix ITBM3.0 not work after HWP enabled. We can remove this patch, but ITBM3.0 will not work when HWP enabled" Are you familiar with this issue? I want the original behaviour of the "Auto" setting, as it is the only way for control to go to the OS with HWP available but disabled. ... Doug
On Tue, 2021-09-14 at 11:41 -0700, Doug Smythies wrote: > On Tue, Sep 7, 2021 at 8:43 PM Doug Smythies <dsmythies@telus.net> > wrote: > > [...] > > The intel_pstate driver works fine. > > Hi Srinivas, Hi Doug, > > I heard back from ASUS, and they now confirm that they > did change the behaviour of the "Auto" setting in BIOS > version 2103. They say they did it to fix an issue with > ITB3.0, which I assume means Intel Turbo Boost 3.0. > I'll copy and paste the relevant portion of the email > below: > > " I am in direct contact with the engineers. > Here is the result from their test: > > In BIOS 2103,the “Auto” setting transfers control to > the OS with HWP available and enabled. > > This is side effect to fix ITBM3.0 not work after HWP enabled. > We can remove this patch, but ITBM3.0 will not work when HWP enabled" > > Are you familiar with this issue? No. I think they mean that they need to expose ACPI CPPC information. It is possible they only expose ACPI CPPC information when HWP feature is available. But not sure why it requires HWP enable also. We (on Linux) depend on ACPI CPPC for turbo 3.0, but don't require HWP to be enabled by default. Thanks, Srinivas > > I want the original behaviour of the "Auto" setting, as it is > the only way for control to go to the OS with HWP > available but disabled. > > ... Doug
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index f0401064d7aa..28c9733e0dce 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -2087,6 +2087,7 @@ static const struct x86_cpu_id intel_pstate_cpu_ids[] = { X86_MATCH(ATOM_GOLDMONT, core_funcs), X86_MATCH(ATOM_GOLDMONT_PLUS, core_funcs), X86_MATCH(SKYLAKE_X, core_funcs), + X86_MATCH(ICELAKE_X, core_funcs), {} }; MODULE_DEVICE_TABLE(x86cpu, intel_pstate_cpu_ids);
Users may disable HWP in firmware, in which case intel_pstate wouldn't load unless the CPU model is explicitly supported. Add ICELAKE_X to the list of CPUs that can register intel_pstate while not advertising the HWP capability. Without this change, an ICELAKE_X in no-HWP mode could only use the acpi_cpufreq frequency scaling driver. See also commit d8de7a44e11f ("cpufreq: intel_pstate: Add Skylake servers support"). Signed-off-by: Giovanni Gherdovich <ggherdovich@suse.cz> --- This replaces https://lore.kernel.org/lkml/20210513075930.22657-1-ggherdovich@suse.cz drivers/cpufreq/intel_pstate.c | 1 + 1 file changed, 1 insertion(+)