[PATCH v2 2/2] drm/i915/xe2lpd: Update C20 algorithm to include tx_misc

[Gustavo Sousa <gustavo.sousa@intel.com>]

There has been an update to the BSpec in which we need to set
tx_misc=0x5 field for C20 TX Context programming for HDMI TMDS for
Xe2_LPD and newer. That field is mapped to the bits 7:0 of
SRAM_GENERIC_<A/B>_TX_CNTX_CFG_1, which in turn translates to tx[1] of
our state struct. Update the algorithm to reflect this change.

v2:
  - Fix Bspec reference (Sai Teja)
  - Use struct intel_display instead of drm_i915_private. (Jani)
  - Use the correct bit width for C20_PHY_TX_MISC_MASK. (Jani)

Bspec: 74491
Cc: Dnyaneshwar Bhadane <dnyaneshwar.bhadane@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Sai Teja Pottumuttu <sai.teja.pottumuttu@intel.com> #v1
Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com>
---
 drivers/gpu/drm/i915/display/intel_cx0_phy.c      | 9 ++++++++-
 drivers/gpu/drm/i915/display/intel_cx0_phy_regs.h | 2 ++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/display/intel_cx0_phy.c b/drivers/gpu/drm/i915/display/intel_cx0_phy.c
index 996c3c6edd41..9202f0b9e8b3 100644
--- a/drivers/gpu/drm/i915/display/intel_cx0_phy.c
+++ b/drivers/gpu/drm/i915/display/intel_cx0_phy.c
@@ -2144,6 +2144,7 @@ static void intel_c10pll_dump_hw_state(struct drm_i915_private *i915,
 
 static int intel_c20_compute_hdmi_tmds_pll(struct intel_crtc_state *crtc_state)
 {
+	struct intel_display *display = to_intel_display(crtc_state);
 	struct intel_c20pll_state *pll_state = &crtc_state->dpll_hw_state.cx0pll.c20;
 	u64 datarate;
 	u64 mpll_tx_clk_div;
@@ -2153,6 +2154,7 @@ static int intel_c20_compute_hdmi_tmds_pll(struct intel_crtc_state *crtc_state)
 	u64 mpll_multiplier;
 	u64 mpll_fracn_quot;
 	u64 mpll_fracn_rem;
+	u16 tx_misc;
 	u8  mpllb_ana_freq_vco;
 	u8  mpll_div_multiplier;
 
@@ -2172,6 +2174,11 @@ static int intel_c20_compute_hdmi_tmds_pll(struct intel_crtc_state *crtc_state)
 	mpll_div_multiplier = min_t(u8, div64_u64((vco_freq * 16 + (datarate >> 1)),
 						  datarate), 255);
 
+	if (DISPLAY_VER(display) >= 20)
+		tx_misc = 0x5;
+	else
+		tx_misc = 0x0;
+
 	if (vco_freq <= DATARATE_3000000000)
 		mpllb_ana_freq_vco = MPLLB_ANA_FREQ_VCO_3;
 	else if (vco_freq <= DATARATE_3500000000)
@@ -2183,7 +2190,7 @@ static int intel_c20_compute_hdmi_tmds_pll(struct intel_crtc_state *crtc_state)
 
 	pll_state->clock	= crtc_state->port_clock;
 	pll_state->tx[0]	= 0xbe88;
-	pll_state->tx[1]	= 0x9800;
+	pll_state->tx[1]	= 0x9800 | C20_PHY_TX_MISC(tx_misc);
 	pll_state->tx[2]	= 0x0000;
 	pll_state->cmn[0]	= 0x0500;
 	pll_state->cmn[1]	= 0x0005;
diff --git a/drivers/gpu/drm/i915/display/intel_cx0_phy_regs.h b/drivers/gpu/drm/i915/display/intel_cx0_phy_regs.h
index ab3ae110b68f..fdce4152a7c9 100644
--- a/drivers/gpu/drm/i915/display/intel_cx0_phy_regs.h
+++ b/drivers/gpu/drm/i915/display/intel_cx0_phy_regs.h
@@ -280,6 +280,8 @@
 #define PHY_C20_B_TX_CNTX_CFG(i915, idx) \
 		((_IS_XE2HPD_C20(i915) ? _XE2HPD_C20_B_TX_CNTX_CFG : _MTL_C20_B_TX_CNTX_CFG) - (idx))
 #define   C20_PHY_TX_RATE		REG_GENMASK(2, 0)
+#define   C20_PHY_TX_MISC_MASK		REG_GENMASK16(7, 0)
+#define   C20_PHY_TX_MISC(val)		REG_FIELD_PREP16(C20_PHY_TX_MISC_MASK, (val))
 
 #define PHY_C20_A_CMN_CNTX_CFG(i915, idx) \
 		((_IS_XE2HPD_C20(i915) ? _XE2HPD_C20_A_CMN_CNTX_CFG : _MTL_C20_A_CMN_CNTX_CFG) - (idx))
-- 
2.47.0