update docs

README.md

@@ -207,10 +207,11 @@ The following are the bit definitions for the interrupt registers:
 |5|RXA|1|Receive FIFO level is Above Threshold.|
 ### Clock Gating
 The IP has clock gating feature, enabling the selective activation and deactivation of the clock as required through the ``GCLK`` register. This functionality is implemented through the ``ef_util_gating_cell``, which is part of the the common modules library, [ef_util_lib.v](https://github.com/efabless/EF_IP_UTIL/blob/main/hdl/ef_util_lib.v). By default, the cell operates with a behavioral implementation, but when the ``CLKG_SKY130_HD`` macro is enabled, the ``sky130_fd_sc_hd__dlclkp_4`` clock gating cell is used.
-**Note:** If you choose the [OpenLane2](https://github.com/efabless/openlane2) flow for implementation and would like to add the clock gating feature, you need to add ``SKY130`` macro to the ``VERILOG_DEFINES`` configuration variable. Update the YAML configuration file as follows: 
+
+**Note:** If you choose the [OpenLane2](https://github.com/efabless/openlane2) flow for implementation and would like to add the clock gating feature, you need to add ``CLKG_SKY130_HD`` macro to the ``VERILOG_DEFINES`` configuration variable. Update the YAML configuration file as follows: 
 ```
 VERILOG_DEFINES:
-- SKY130
+- CLKG_SKY130_HD
 ```
 
 ### The Interface