Re: [PATCH] drm/i915/rps: convert rps interface to struct drm_device

[Jani Nikula <jani.nikula@intel.com>]

On Thu, 23 Oct 2025, Tvrtko Ursulin <tursulin@ursulin.net> wrote:
> On 23/10/2025 09:55, Jani Nikula wrote:
>> On Thu, 23 Oct 2025, Tvrtko Ursulin <tursulin@ursulin.net> wrote:
>>> On 23/10/2025 08:45, Jani Nikula wrote:
>>>> Reduce the display dependency on struct drm_i915_private and i915_drv.h
>>>> by converting the rps interface to struct drm_device.
>>>>
>>>> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
>>>> ---
>>>>    .../gpu/drm/i915/display/intel_display_rps.c   | 12 +++++-------
>>>>    drivers/gpu/drm/i915/gt/intel_rps.c            | 18 ++++++++++++++++--
>>>>    drivers/gpu/drm/i915/gt/intel_rps.h            |  7 ++++---
>>>>    3 files changed, 25 insertions(+), 12 deletions(-)
>>>>
>>>> diff --git a/drivers/gpu/drm/i915/display/intel_display_rps.c b/drivers/gpu/drm/i915/display/intel_display_rps.c
>>>> index 82ea1ec482e4..8bf0f8cb6574 100644
>>>> --- a/drivers/gpu/drm/i915/display/intel_display_rps.c
>>>> +++ b/drivers/gpu/drm/i915/display/intel_display_rps.c
>>>> @@ -3,12 +3,14 @@
>>>>     * Copyright © 2023 Intel Corporation
>>>>     */
>>>>    
>>>> +#include <linux/dma-fence.h>
>>>> +
>>>>    #include <drm/drm_crtc.h>
>>>>    #include <drm/drm_vblank.h>
>>>>    
>>>>    #include "gt/intel_rps.h"
>>>> -#include "i915_drv.h"
>>>>    #include "i915_reg.h"
>>>> +#include "i915_request.h"
>>>>    #include "intel_display_core.h"
>>>>    #include "intel_display_irq.h"
>>>>    #include "intel_display_rps.h"
>>>> @@ -77,12 +79,10 @@ void intel_display_rps_mark_interactive(struct intel_display *display,
>>>>    					struct intel_atomic_state *state,
>>>>    					bool interactive)
>>>>    {
>>>> -	struct drm_i915_private *i915 = to_i915(display->drm);
>>>> -
>>>>    	if (state->rps_interactive == interactive)
>>>>    		return;
>>>>    
>>>> -	intel_rps_mark_interactive(&to_gt(i915)->rps, interactive);
>>>> +	intel_rps_mark_interactive(display->drm, interactive);
>>>>    	state->rps_interactive = interactive;
>>>>    }
>>>>    
>>>> @@ -102,7 +102,5 @@ void ilk_display_rps_disable(struct intel_display *display)
>>>>    
>>>>    void ilk_display_rps_irq_handler(struct intel_display *display)
>>>>    {
>>>> -	struct drm_i915_private *i915 = to_i915(display->drm);
>>>> -
>>>> -	gen5_rps_irq_handler(&to_gt(i915)->rps);
>>>> +	gen5_rps_irq_handler(display->drm);
>>>>    }
>>>> diff --git a/drivers/gpu/drm/i915/gt/intel_rps.c b/drivers/gpu/drm/i915/gt/intel_rps.c
>>>> index b01c837ab646..a2c502609d96 100644
>>>> --- a/drivers/gpu/drm/i915/gt/intel_rps.c
>>>> +++ b/drivers/gpu/drm/i915/gt/intel_rps.c
>>>> @@ -782,7 +782,7 @@ static void gen6_rps_set_thresholds(struct intel_rps *rps, u8 val)
>>>>    	mutex_unlock(&rps->power.mutex);
>>>>    }
>>>>    
>>>> -void intel_rps_mark_interactive(struct intel_rps *rps, bool interactive)
>>>> +static void _intel_rps_mark_interactive(struct intel_rps *rps, bool interactive)
>>>>    {
>>>>    	GT_TRACE(rps_to_gt(rps), "mark interactive: %s\n",
>>>>    		 str_yes_no(interactive));
>>>> @@ -798,6 +798,13 @@ void intel_rps_mark_interactive(struct intel_rps *rps, bool interactive)
>>>>    	mutex_unlock(&rps->power.mutex);
>>>>    }
>>>>    
>>>> +void intel_rps_mark_interactive(struct drm_device *drm, bool interactive)
>>>> +{
>>>> +	struct drm_i915_private *i915 = to_i915(drm);
>>>> +
>>>> +	_intel_rps_mark_interactive(&to_gt(i915)->rps, interactive);
>>>> +}
>>>> +
>>>>    static int gen6_rps_set(struct intel_rps *rps, u8 val)
>>>>    {
>>>>    	struct intel_uncore *uncore = rps_to_uncore(rps);
>>>> @@ -1953,7 +1960,7 @@ void gen6_rps_irq_handler(struct intel_rps *rps, u32 pm_iir)
>>>>    			"Command parser error, pm_iir 0x%08x\n", pm_iir);
>>>>    }
>>>>    
>>>> -void gen5_rps_irq_handler(struct intel_rps *rps)
>>>> +static void _gen5_rps_irq_handler(struct intel_rps *rps)
>>>>    {
>>>>    	struct intel_uncore *uncore = rps_to_uncore(rps);
>>>>    	u32 busy_up, busy_down, max_avg, min_avg;
>>>> @@ -1987,6 +1994,13 @@ void gen5_rps_irq_handler(struct intel_rps *rps)
>>>>    	spin_unlock(&mchdev_lock);
>>>>    }
>>>>    
>>>> +void gen5_rps_irq_handler(struct drm_device *drm)
>>>> +{
>>>> +	struct drm_i915_private *i915 = to_i915(drm);
>>>> +
>>>> +	_gen5_rps_irq_handler(&to_gt(i915)->rps);
>>>> +}
>>>> +
>>>>    void intel_rps_init_early(struct intel_rps *rps)
>>>>    {
>>>>    	mutex_init(&rps->lock);
>>>> diff --git a/drivers/gpu/drm/i915/gt/intel_rps.h b/drivers/gpu/drm/i915/gt/intel_rps.h
>>>> index 92fb01f5a452..c817a70fb3aa 100644
>>>> --- a/drivers/gpu/drm/i915/gt/intel_rps.h
>>>> +++ b/drivers/gpu/drm/i915/gt/intel_rps.h
>>>> @@ -9,8 +9,9 @@
>>>>    #include "intel_rps_types.h"
>>>>    #include "i915_reg_defs.h"
>>>>    
>>>> -struct i915_request;
>>>> +struct drm_device;
>>>>    struct drm_printer;
>>>> +struct i915_request;
>>>>    
>>>>    #define GT_FREQUENCY_MULTIPLIER 50
>>>>    #define GEN9_FREQ_SCALER 3
>>>> @@ -33,7 +34,7 @@ u32 intel_rps_get_boost_frequency(struct intel_rps *rps);
>>>>    int intel_rps_set_boost_frequency(struct intel_rps *rps, u32 freq);
>>>>    
>>>>    int intel_rps_set(struct intel_rps *rps, u8 val);
>>>> -void intel_rps_mark_interactive(struct intel_rps *rps, bool interactive);
>>>> +void intel_rps_mark_interactive(struct drm_device *drm, bool interactive);
>>>
>>> This one breaks the design a bit since RPS is supposed to be per GT. On
>>> the other hand intel_display_rps_mark_interactive is the only caller so
>>> if it only wants to care about the primary GT thats probably okay.
>>>
>>> Presumably you don't want a for_each_gt in the display code either.
>>>
>>> Would it work to put a helper which did it for you somewhere one level
>>> up from per gt (gt/) components? Sounds like for the end goal of proper
>>> abstraction that would be the way. Getting rid of the #ifdef from
>>> intel_display_rps.h and each driver would then implement the required
>>> hooks to do what they want.
>> 
>> See [1]. We might add display->parent->rps, and call the hooks via
>> that. But even so, they'll need interfaces that are independent of gt,
>> so something like the patch at hand will be needed. I don't particularly
>> care if the functions on i915 core side are in gt/ or somewhere else.
>
> Okay, but from my point of view intel_rps_mark_interactive() should 
> remain taking rps. This is the design of all components under gt/ and I 
> do not think we should break it for this case. So for me a new helper 
> somewhere one level above gt/ sounds like the way to go. That one is 
> then perfectly fine to operate on the device.

Okay.

> Pull out existing 
> intel_display_rps_mark_interactive() out from display and rename to 
> something like intel_display_mark_interactive(). As a first step. Xe can 
> stub it out in compat headers rather than #ifdefs in the display code.

intel_display_rps_mark_interactive() needs to remain in display, because
it handles display structures. struct drm_device is the abstraction
between display and i915 core.

Looks like the whole thing is going to have to wait for [1] to land, and
we'll add the function pointers there, which will then have some
functions that do exactly the same thing as the wrappers I added here
do, but will have to find a new location for them somewhere in i915 core
that is not gt/.


BR,
Jani.

>
> Regards,
>
> Tvrtko
>> [1] https://lore.kernel.org/r/20251022085548.876150-2-jouni.hogander@intel.com
>> 
>>>
>>> Regards,
>>>
>>> Tvrtko
>>>>    int intel_gpu_freq(struct intel_rps *rps, int val);
>>>>    int intel_freq_opcode(struct intel_rps *rps, int val);
>>>> @@ -64,7 +65,7 @@ bool rps_read_mask_mmio(struct intel_rps *rps, i915_reg_t reg32, u32 mask);
>>>>    
>>>>    void gen6_rps_frequency_dump(struct intel_rps *rps, struct drm_printer *p);
>>>>    
>>>> -void gen5_rps_irq_handler(struct intel_rps *rps);
>>>> +void gen5_rps_irq_handler(struct drm_device *drm);
>>>>    void gen6_rps_irq_handler(struct intel_rps *rps, u32 pm_iir);
>>>>    void gen11_rps_irq_handler(struct intel_rps *rps, u32 pm_iir);
>>>>    
>>>
>> 
>

-- 
Jani Nikula, Intel