Re: [PATCH v2 1/2] drm/xe: Make read_perf_limit_reasons globally accessible

[Rodrigo Vivi <rodrigo.vivi@intel.com>]

On Wed, Feb 14, 2024 at 12:21:36PM -0800, John Harrison wrote:
> On 2/14/2024 05:54, Rodrigo Vivi wrote:
> > On Tue, Feb 13, 2024 at 06:12:11PM -0800, John Harrison wrote:
> > > On 2/13/2024 07:22, Rodrigo Vivi wrote:
> > > > On Mon, Feb 12, 2024 at 04:34:25PM -0800, John.C.Harrison@Intel.com wrote:
> > > > > From: John Harrison <John.C.Harrison@Intel.com>
> > > > > 
> > > > > Other driver code beyond the sysfs interface wants to know about
> > > > > throttling. So move the query function out of sysfs.
> > > > > 
> > > > > Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
> > > > > ---
> > > > >    drivers/gpu/drm/xe/xe_gt_freq.c           | 15 +++++++++++
> > > > >    drivers/gpu/drm/xe/xe_gt_freq.h           |  4 +++
> > > > >    drivers/gpu/drm/xe/xe_gt_throttle_sysfs.c | 31 ++++++++---------------
> > > > >    3 files changed, 29 insertions(+), 21 deletions(-)
> > > > > 
> > > > > diff --git a/drivers/gpu/drm/xe/xe_gt_freq.c b/drivers/gpu/drm/xe/xe_gt_freq.c
> > > > > index e5b0f4ecdbe8..51645a24009e 100644
> > > > > --- a/drivers/gpu/drm/xe/xe_gt_freq.c
> > > > > +++ b/drivers/gpu/drm/xe/xe_gt_freq.c
> > > > > @@ -11,7 +11,10 @@
> > > > >    #include <drm/drm_managed.h>
> > > > >    #include <drm/drm_print.h>
> > > > > +#include "regs/xe_gt_regs.h"
> > > > >    #include "xe_device_types.h"
> > > > > +#include "xe_mmio.h"
> > > > > +#include "xe_gt.h"
> > > > >    #include "xe_gt_sysfs.h"
> > > > >    #include "xe_gt_throttle_sysfs.h"
> > > > >    #include "xe_guc_pc.h"
> > > > > @@ -220,3 +223,15 @@ void xe_gt_freq_init(struct xe_gt *gt)
> > > > >    	xe_gt_throttle_sysfs_init(gt);
> > > > >    }
> > > > > +
> > > > > +u32 xe_read_perf_limit_reasons(struct xe_gt *gt)
> > > > > +{
> > > > > +	u32 reg;
> > > > > +
> > > > > +	if (xe_gt_is_media_type(gt))
> > > > > +		reg = xe_mmio_read32(gt, MTL_MEDIA_PERF_LIMIT_REASONS);
> > > > > +	else
> > > > > +		reg = xe_mmio_read32(gt, GT0_PERF_LIMIT_REASONS);
> > > > > +
> > > > > +	return reg;
> > > > > +}
> > > > > diff --git a/drivers/gpu/drm/xe/xe_gt_freq.h b/drivers/gpu/drm/xe/xe_gt_freq.h
> > > > > index f3fe3c90491a..89be518b4967 100644
> > > > > --- a/drivers/gpu/drm/xe/xe_gt_freq.h
> > > > > +++ b/drivers/gpu/drm/xe/xe_gt_freq.h
> > > > > @@ -6,8 +6,12 @@
> > > > >    #ifndef _XE_GT_FREQ_H_
> > > > >    #define _XE_GT_FREQ_H_
> > > > > +#include <linux/types.h>
> > > > > +
> > > > >    struct xe_gt;
> > > > >    void xe_gt_freq_init(struct xe_gt *gt);
> > > > > +u32 xe_read_perf_limit_reasons(struct xe_gt *gt);
> > > > this component is xe_gt_freq, not xe_ nor xe_read or xe_read_perf.
> > > > Please use the right namespace prefixes.
> > > Argh! Forgot to update that.
> > > 
> > > > But besides the namespace, I don't believe that these limits
> > > > belong to xe_gt_freq anyway... why are you taking that from the
> > > > throttle reasons and moving here?
> > > > 
> > > > What about removing the 'sysfs' name from the xe_gt_throttle
> > > > component and making that to export a function
> > > > xe_gt_throttle_get_limit_reasons(struct xe_gt *gt)
> > > > ?
> > > Because that seems like a lot of unnecessary churn. The intention is to
> > > simply add the throttle register to debug prints so that CI bug reports can
> > > be triaged more effectively. Re-writing the entire sysfs file to split it up
> > > into multiple units is not worth the effort when all that is required is to
> > > export the function to read a register.
> > No, that's not what I meant... I don't believe we need to split the file.
> > just remove the 'sysfs' portion of the name of the component itself,
> > so we have a component responsible for providing throttle information, either
> > with direct exposing the sysfs and also with the exported functions that can
> > be accessed by any other component that might make usage of the throttle
> > information.
> Still not sure I follow. You mean rename the files to xe_gt_throttle.[ch]
> and rename the exported init function to xe_gt_throttle_init() but don't
> change anything else? Leave all the sysfs code in the single file? And have
> xe_gt_throttle_init() as just a stub wrapper around a static
> gt_throttle_sysfs_init() or keep it as a single level init function that is
> generically named but only does sysfs initialisation?

I mean something like this:
https://paste.centos.org/view/d3d2cc77

> 
> John.
> 
> > > John.
> > > 
> > > 
> > > > Thanks,
> > > > Rodrigo.
> > > > 
> > > > > +
> > > > >    #endif
> > > > > diff --git a/drivers/gpu/drm/xe/xe_gt_throttle_sysfs.c b/drivers/gpu/drm/xe/xe_gt_throttle_sysfs.c
> > > > > index 63d640591a52..89d9f89962ad 100644
> > > > > --- a/drivers/gpu/drm/xe/xe_gt_throttle_sysfs.c
> > > > > +++ b/drivers/gpu/drm/xe/xe_gt_throttle_sysfs.c
> > > > > @@ -8,6 +8,7 @@
> > > > >    #include <regs/xe_gt_regs.h>
> > > > >    #include "xe_device.h"
> > > > >    #include "xe_gt.h"
> > > > > +#include "xe_gt_freq.h"
> > > > >    #include "xe_gt_sysfs.h"
> > > > >    #include "xe_gt_throttle_sysfs.h"
> > > > >    #include "xe_mmio.h"
> > > > > @@ -34,77 +35,65 @@ dev_to_gt(struct device *dev)
> > > > >    	return kobj_to_gt(dev->kobj.parent);
> > > > >    }
> > > > > -static u32 read_perf_limit_reasons(struct xe_gt *gt)
> > > > > -{
> > > > > -	u32 reg;
> > > > > -
> > > > > -	if (xe_gt_is_media_type(gt))
> > > > > -		reg = xe_mmio_read32(gt, MTL_MEDIA_PERF_LIMIT_REASONS);
> > > > > -	else
> > > > > -		reg = xe_mmio_read32(gt, GT0_PERF_LIMIT_REASONS);
> > > > > -
> > > > > -	return reg;
> > > > > -}
> > > > > -
> > > > >    static u32 read_status(struct xe_gt *gt)
> > > > >    {
> > > > > -	u32 status = read_perf_limit_reasons(gt) & GT0_PERF_LIMIT_REASONS_MASK;
> > > > > +	u32 status = xe_read_perf_limit_reasons(gt) & GT0_PERF_LIMIT_REASONS_MASK;
> > > > >    	return status;
> > > > >    }
> > > > >    static u32 read_reason_pl1(struct xe_gt *gt)
> > > > >    {
> > > > > -	u32 pl1 = read_perf_limit_reasons(gt) & POWER_LIMIT_1_MASK;
> > > > > +	u32 pl1 = xe_read_perf_limit_reasons(gt) & POWER_LIMIT_1_MASK;
> > > > >    	return pl1;
> > > > >    }
> > > > >    static u32 read_reason_pl2(struct xe_gt *gt)
> > > > >    {
> > > > > -	u32 pl2 = read_perf_limit_reasons(gt) & POWER_LIMIT_2_MASK;
> > > > > +	u32 pl2 = xe_read_perf_limit_reasons(gt) & POWER_LIMIT_2_MASK;
> > > > >    	return pl2;
> > > > >    }
> > > > >    static u32 read_reason_pl4(struct xe_gt *gt)
> > > > >    {
> > > > > -	u32 pl4 = read_perf_limit_reasons(gt) & POWER_LIMIT_4_MASK;
> > > > > +	u32 pl4 = xe_read_perf_limit_reasons(gt) & POWER_LIMIT_4_MASK;
> > > > >    	return pl4;
> > > > >    }
> > > > >    static u32 read_reason_thermal(struct xe_gt *gt)
> > > > >    {
> > > > > -	u32 thermal = read_perf_limit_reasons(gt) & THERMAL_LIMIT_MASK;
> > > > > +	u32 thermal = xe_read_perf_limit_reasons(gt) & THERMAL_LIMIT_MASK;
> > > > >    	return thermal;
> > > > >    }
> > > > >    static u32 read_reason_prochot(struct xe_gt *gt)
> > > > >    {
> > > > > -	u32 prochot = read_perf_limit_reasons(gt) & PROCHOT_MASK;
> > > > > +	u32 prochot = xe_read_perf_limit_reasons(gt) & PROCHOT_MASK;
> > > > >    	return prochot;
> > > > >    }
> > > > >    static u32 read_reason_ratl(struct xe_gt *gt)
> > > > >    {
> > > > > -	u32 ratl = read_perf_limit_reasons(gt) & RATL_MASK;
> > > > > +	u32 ratl = xe_read_perf_limit_reasons(gt) & RATL_MASK;
> > > > >    	return ratl;
> > > > >    }
> > > > >    static u32 read_reason_vr_thermalert(struct xe_gt *gt)
> > > > >    {
> > > > > -	u32 thermalert = read_perf_limit_reasons(gt) & VR_THERMALERT_MASK;
> > > > > +	u32 thermalert = xe_read_perf_limit_reasons(gt) & VR_THERMALERT_MASK;
> > > > >    	return thermalert;
> > > > >    }
> > > > >    static u32 read_reason_vr_tdc(struct xe_gt *gt)
> > > > >    {
> > > > > -	u32 tdc = read_perf_limit_reasons(gt) & VR_TDC_MASK;
> > > > > +	u32 tdc = xe_read_perf_limit_reasons(gt) & VR_TDC_MASK;
> > > > >    	return tdc;
> > > > >    }
> > > > > -- 
> > > > > 2.43.0
> > > > > 
>