Re: [Intel-gfx] [PATCH 1/1] drm/i915/mtl: Enable Idle Messaging for GSC CS

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

On Tue, Nov 15, 2022 at 07:14:40PM +0530, Badal Nilawar wrote:
> From: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
> 
> By defaut idle mesaging is disabled for GSC CS so to unblock RC6
> entry on media tile idle messaging need to be enabled.
> 
> v2:
>  - Fix review comments (Vinay)
>  - Set GSC idle hysterisis to 5 us (Badal)

btw, no need for the cover letter in single/standalone patches.
This history here is enough.

> 
> Bspec: 71496
> 
> Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
> Signed-off-by: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
> Signed-off-by: Badal Nilawar <badal.nilawar@intel.com>
> ---
>  drivers/gpu/drm/i915/gt/intel_engine_pm.c | 18 ++++++++++++++++++
>  drivers/gpu/drm/i915/gt/intel_gt_regs.h   |  4 ++++
>  2 files changed, 22 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/gt/intel_engine_pm.c b/drivers/gpu/drm/i915/gt/intel_engine_pm.c
> index b0a4a2dbe3ee..5522885b2db0 100644
> --- a/drivers/gpu/drm/i915/gt/intel_engine_pm.c
> +++ b/drivers/gpu/drm/i915/gt/intel_engine_pm.c
> @@ -15,6 +15,22 @@
>  #include "intel_rc6.h"
>  #include "intel_ring.h"
>  #include "shmem_utils.h"
> +#include "intel_gt_regs.h"
> +
> +static void intel_gsc_idle_msg_enable(struct intel_engine_cs *engine)
> +{
> +	struct drm_i915_private *i915 = engine->i915;
> +
> +	if (IS_METEORLAKE(i915) && engine->id == GSC0) {
> +		intel_uncore_write(engine->gt->uncore,
> +				   RC_PSMI_CTRL_GSCCS,
> +				   _MASKED_BIT_DISABLE(IDLE_MSG_DISABLE));
> +		/* 5 us hysterisis */

typo

> +		intel_uncore_write(engine->gt->uncore,
> +				   PWRCTX_MAXCNT_GSCCS,
> +				   0xA);

you said 5 above, but used 10 here, why?

> +	}
> +}
>  
>  static void dbg_poison_ce(struct intel_context *ce)
>  {
> @@ -275,6 +291,8 @@ void intel_engine_init__pm(struct intel_engine_cs *engine)
>  
>  	intel_wakeref_init(&engine->wakeref, rpm, &wf_ops);
>  	intel_engine_init_heartbeat(engine);
> +
> +	intel_gsc_idle_msg_enable(engine);
>  }
>  
>  /**
> diff --git a/drivers/gpu/drm/i915/gt/intel_gt_regs.h b/drivers/gpu/drm/i915/gt/intel_gt_regs.h
> index 07031e03f80c..20472eb15364 100644
> --- a/drivers/gpu/drm/i915/gt/intel_gt_regs.h
> +++ b/drivers/gpu/drm/i915/gt/intel_gt_regs.h
> @@ -913,6 +913,10 @@
>  #define  MSG_IDLE_FW_MASK	REG_GENMASK(13, 9)
>  #define  MSG_IDLE_FW_SHIFT	9
>  
> +#define	RC_PSMI_CTRL_GSCCS	_MMIO(0x11a050)
> +#define	  IDLE_MSG_DISABLE	BIT(0)

REG_BIT should be preferred.

> +#define PWRCTX_MAXCNT_GSCCS	_MMIO(0x11a054)
> +
>  #define FORCEWAKE_MEDIA_GEN9			_MMIO(0xa270)
>  #define FORCEWAKE_RENDER_GEN9			_MMIO(0xa278)
>  
> -- 
> 2.25.1
>