Re: [PATCH v2 07/13] drm/i915: Extract intel_dsb_supported()

[Borah, Chaitanya Kumar]

On 9/9/2026 9:47 PM, Ville Syrjala wrote:

From: Ville Syrjälä <ville.syrj...@linux.intel.com>

Extract the "do we have a DSB and should be use it?" check

typo: we

into a helper. This mirrors intel_flipq_supported() and should
help unify the logic around selecting the codepath which will
be used to perform the commit (mmio vs. DSB. vs. flip queue).

Reviewed-by: Chaitanya Kumar Borah <chaitanya.kumar.bo...@intel.com>

Signed-off-by: Ville Syrjälä <ville.syrj...@linux.intel.com>
---
  drivers/gpu/drm/i915/display/intel_dsb.c | 13 +++++++++----
  drivers/gpu/drm/i915/display/intel_dsb.h |  1 +
  2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_dsb.c 
b/drivers/gpu/drm/i915/display/intel_dsb.c
index d9a270362a82..8e01e1eed291 100644
--- a/drivers/gpu/drm/i915/display/intel_dsb.c
+++ b/drivers/gpu/drm/i915/display/intel_dsb.c
@@ -1025,6 +1025,14 @@ void intel_dsb_wait(struct intel_dsb *dsb)
                          dsb_error_int_status(display) | DSB_PROG_INT_STATUS);
  }

+bool intel_dsb_supported(struct intel_display *display)

+{
+       if (!display->params.enable_dsb)
+               return false;
+
+       return HAS_DSB(display);
+}
+
  /**
   * intel_dsb_prepare() - Allocate, pin and map the DSB command buffer.
   * @state: the atomic state
@@ -1049,10 +1057,7 @@ struct intel_dsb *intel_dsb_prepare(struct 
intel_atomic_state *state,
        struct intel_dsb *dsb;
        unsigned int size;

- if (!HAS_DSB(display))

-               return NULL;
-
-       if (!display->params.enable_dsb)
+       if (!intel_dsb_supported(display))
                return NULL;

dsb = kzalloc_obj(*dsb);

diff --git a/drivers/gpu/drm/i915/display/intel_dsb.h 
b/drivers/gpu/drm/i915/display/intel_dsb.h
index 3dcca9ed5371..87d9c90da08f 100644
--- a/drivers/gpu/drm/i915/display/intel_dsb.h
+++ b/drivers/gpu/drm/i915/display/intel_dsb.h
@@ -26,6 +26,7 @@ enum intel_dsb_id {
        I915_MAX_DSBS,
  };

+bool intel_dsb_supported(struct intel_display *display);

  unsigned int intel_dsb_size(struct intel_dsb *dsb);
  unsigned int intel_dsb_head(struct intel_dsb *dsb);
  struct intel_dsb *intel_dsb_prepare(struct intel_atomic_state *state,