[PATCH v6 0/2] drm/i915/display: Power request asserting/deasserting

[Jani Nikula]

On Wed, 27 Nov 2024, Mika Kahola <mika.kahola at intel.com> wrote:
> There is a HW issue that arises when there are race conditions
> between TCSS entering/exiting TC7 or TC10 states while the
> driver is asserting/deasserting TCSS power request. As a
> workaround, Display driver will implement a mailbox sequence
> to ensure that the TCSS is in TC0 when TCSS power request is
> asserted/deasserted.
>
> The sequence is the following
>
> 1. Read mailbox command status and wait until run/busy bit is
>    clear
> 2. Write mailbox data value '1' for power request asserting
>    and '0' for power request deasserting
> 3. Write mailbox command run/busy bit and command value with 0x1
> 4. Read mailbox command and wait until run/busy bit is clear
>    before continuing power request.
>
> while at it, let's start using struct intel_display instead of
> struct drm_i915_private as well.
>
> Signed-off-by: Mika Kahola <mika.kahola at intel.com>

Acked-by: Jani Nikula <jani.nikula at intel.com>


>
> Mika Kahola (2):
>   drm/i915/xe3lpd: Power request asserting/deasserting
>   drm/i915/display: Use struct intel_display instead of struct
>     drm_i915_private
>
>  .../gpu/drm/i915/display/intel_cx0_phy_regs.h |  7 ++++
>  drivers/gpu/drm/i915/display/intel_tc.c       | 39 +++++++++++++++++--
>  2 files changed, 42 insertions(+), 4 deletions(-)

-- 
Jani Nikula, Intel