drm/i915/dsi/xelpd: Fix the bit mask for wakeup GB

v2: Fix the typo, move out the hardcoding from
    macro(Jani, Ville)

Fixes: f87c46c431 ("drm/i915/dsi/xelpd: Add WA to program LP to HS wakeup guardband")
Signed-off-by: Vandita Kulkarni <vandita.kulkarni@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211019151435.20477-2-vandita.kulkarni@intel.com
(cherry picked from commit 6f07707fa0)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drivers/gpu/drm/i915/display/icl_dsi.c

@@ -1265,7 +1265,8 @@ static void adlp_set_lp_hs_wakeup_gb(struct intel_encoder *encoder)
 	if (DISPLAY_VER(i915) == 13) {
 		for_each_dsi_port(port, intel_dsi->ports)
 			intel_de_rmw(i915, TGL_DSI_CHKN_REG(port),
-				     TGL_DSI_CHKN_LSHS_GB, 0x4);
+				     TGL_DSI_CHKN_LSHS_GB_MASK,
+				     TGL_DSI_CHKN_LSHS_GB(4));
 	}
 }
 

drivers/gpu/drm/i915/i915_reg.h

@@ -11717,7 +11717,9 @@ enum skl_power_gate {
 #define TGL_DSI_CHKN_REG(port)		_MMIO_PORT(port,	\
 						    _TGL_DSI_CHKN_REG_0, \
 						    _TGL_DSI_CHKN_REG_1)
-#define TGL_DSI_CHKN_LSHS_GB			REG_GENMASK(15, 12)
+#define TGL_DSI_CHKN_LSHS_GB_MASK		REG_GENMASK(15, 12)
+#define TGL_DSI_CHKN_LSHS_GB(byte_clocks)	REG_FIELD_PREP(TGL_DSI_CHKN_LSHS_GB_MASK, \
+							       (byte_clocks))
 
 /* Display Stream Splitter Control */
 #define DSS_CTL1				_MMIO(0x67400)