drm/i915/xe2lpd: Move D2D enable/disable
Bits to enable/disable and check state for D2D moved from
XELPDP_PORT_BUF_CTL1 to DDI_BUF_CTL (now named DDI_CTL_DE in the spec).
Make the functions mtl_ddi_disable_d2d() and mtl_ddi_enable_d2d generic
to work with multiple reg location and bitfield layout.
v2: Set/Clear XE2LPD_DDI_BUF_D2D_LINK_ENABLE in saved_port_bits when
enabling/disabling D2D so DDI_BUF_CTL is correctly programmed in
other places without overriding these bits (Clint)
v3: Leave saved_port_bits alone as those bits are not meant to be
modified outside of the port initialization. Rather propagate the
additional bit in DDI_BUF_CTL to be set when that register is
written again after D2D is enabled.
Cc: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240126224638.4132016-2-lucas.demarchi@intel.com
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 75bc080..0b9e018 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -5690,6 +5690,8 @@ enum skl_power_gate {
/* Known as DDI_CTL_DE in MTL+ */
#define DDI_BUF_CTL(port) _MMIO_PORT(port, _DDI_BUF_CTL_A, _DDI_BUF_CTL_B)
#define DDI_BUF_CTL_ENABLE (1 << 31)
+#define XE2LPD_DDI_BUF_D2D_LINK_ENABLE REG_BIT(29)
+#define XE2LPD_DDI_BUF_D2D_LINK_STATE REG_BIT(28)
#define DDI_BUF_TRANS_SELECT(n) ((n) << 24)
#define DDI_BUF_EMP_MASK (0xf << 24)
#define DDI_BUF_PHY_LINK_RATE(r) ((r) << 20)
