Enable MAC to transmit LFPS via LT PHY during aux-less alpm.

v2:
- Correct commit description. [Suraj]
- Remove loop as no dependency on the transmitter LT_PHY_CMN_CTL0. [Suraj]
v3: Cosmetic changes. [Suraj]

Cc: Jouni Högander <[email protected]>
Reviewed-by: Suraj Kandpal <[email protected]>
Signed-off-by: Animesh Manna <[email protected]>
---
 drivers/gpu/drm/i915/display/intel_ddi.c      |  5 +++-
 drivers/gpu/drm/i915/display/intel_lt_phy.c   | 27 +++++++++++++++++++
 drivers/gpu/drm/i915/display/intel_lt_phy.h   |  2 ++
 .../gpu/drm/i915/display/intel_lt_phy_regs.h  |  3 +++
 4 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c 
b/drivers/gpu/drm/i915/display/intel_ddi.c
index 002ccd47856d..89ce3d13246a 100644
--- a/drivers/gpu/drm/i915/display/intel_ddi.c
+++ b/drivers/gpu/drm/i915/display/intel_ddi.c
@@ -3777,7 +3777,10 @@ static void mtl_ddi_prepare_link_retrain(struct intel_dp 
*intel_dp,
         *     ii. Enable MAC Transmits LFPS in the "PHY Common Control 0" PIPE
         *         register
         */
-       intel_lnl_mac_transmit_lfps(encoder, crtc_state);
+       if (HAS_LT_PHY(display))
+               intel_xe3plpd_mac_transmit_lfps(encoder, crtc_state);
+       else
+               intel_lnl_mac_transmit_lfps(encoder, crtc_state);
 }
 
 static void intel_ddi_prepare_link_retrain(struct intel_dp *intel_dp,
diff --git a/drivers/gpu/drm/i915/display/intel_lt_phy.c 
b/drivers/gpu/drm/i915/display/intel_lt_phy.c
index a67eb4f7f897..a1a5aed116b7 100644
--- a/drivers/gpu/drm/i915/display/intel_lt_phy.c
+++ b/drivers/gpu/drm/i915/display/intel_lt_phy.c
@@ -6,6 +6,7 @@
 #include <drm/drm_print.h>
 
 #include "i915_reg.h"
+#include "intel_alpm.h"
 #include "intel_cx0_phy.h"
 #include "intel_cx0_phy_regs.h"
 #include "intel_ddi.h"
@@ -2325,3 +2326,29 @@ void intel_xe3plpd_pll_disable(struct intel_encoder 
*encoder)
                intel_lt_phy_pll_disable(encoder);
 
 }
+
+/*
+ * According to HAS we need to enable MAC Transmitting LFPS in the "PHY Common
+ * Control 0" PIPE register in case of AUX Less ALPM is going to be used. This
+ * function is doing that and is called by link retrain sequence.
+ */
+void intel_xe3plpd_mac_transmit_lfps(struct intel_encoder *encoder,
+                                    const struct intel_crtc_state *crtc_state)
+{
+       struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
+       intel_wakeref_t wakeref;
+       u8 owned_lane_mask;
+
+       if (!intel_alpm_is_alpm_aux_less(intel_dp, crtc_state))
+               return;
+
+       wakeref = intel_lt_phy_transaction_begin(encoder);
+
+       owned_lane_mask = intel_lt_phy_get_owned_lane_mask(encoder);
+
+       intel_lt_phy_rmw(encoder, owned_lane_mask, LT_PHY_CMN_CTL_0,
+                        LT_PHY_CMN_LFPS_ENABLE,
+                        LT_PHY_CMN_LFPS_ENABLE, MB_WRITE_COMMITTED);
+
+       intel_lt_phy_transaction_end(encoder, wakeref);
+}
diff --git a/drivers/gpu/drm/i915/display/intel_lt_phy.h 
b/drivers/gpu/drm/i915/display/intel_lt_phy.h
index b7911acd7dcd..5cea01b1756a 100644
--- a/drivers/gpu/drm/i915/display/intel_lt_phy.h
+++ b/drivers/gpu/drm/i915/display/intel_lt_phy.h
@@ -41,6 +41,8 @@ intel_lt_phy_calculate_hdmi_state(struct 
intel_lt_phy_pll_state *lt_state,
 void intel_xe3plpd_pll_enable(struct intel_encoder *encoder,
                              const struct intel_crtc_state *crtc_state);
 void intel_xe3plpd_pll_disable(struct intel_encoder *encoder);
+void intel_xe3plpd_mac_transmit_lfps(struct intel_encoder *encoder,
+                                    const struct intel_crtc_state *crtc_state);
 
 #define HAS_LT_PHY(display) (DISPLAY_VER(display) >= 35)
 
diff --git a/drivers/gpu/drm/i915/display/intel_lt_phy_regs.h 
b/drivers/gpu/drm/i915/display/intel_lt_phy_regs.h
index 98ccc069a69b..c50dbad28b78 100644
--- a/drivers/gpu/drm/i915/display/intel_lt_phy_regs.h
+++ b/drivers/gpu/drm/i915/display/intel_lt_phy_regs.h
@@ -35,6 +35,9 @@
 #define LT_PHY_TXY_CTL10_MAC(idx)      _MMIO(LT_PHY_TXY_CTL10(idx))
 #define  LT_PHY_TX_LANE_ENABLE         REG_BIT8(0)
 
+#define LT_PHY_CMN_CTL_0               (0x800)
+#define  LT_PHY_CMN_LFPS_ENABLE                REG_BIT8(1)
+
 /* LT Phy Vendor Register */
 #define LT_PHY_VDR_0_CONFIG    0xC02
 #define  LT_PHY_VDR_DP_PLL_ENABLE      REG_BIT(7)
-- 
2.29.0

Reply via email to