env: ti: j721e-evm: Add env variable to power on & reset QSGMII PHY in J7200 EVM

MAIN CPSW0 requires the PHY to be powered on and reset for QSGMII
operation. Add a env variable to configure driving "0" on ENET_EXP_PWRDN
controlled by GPIO EXPANDER2 (I2C Addr: 0x22), PIN: 17 and driving "1"
on ENET_EXP_RESETZ controlled by GPIO EXPANDER2 (I2C Addr: 0x22),
PIN: 18.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Reviewed-by: Suman Anna <s-anna@ti.com>
Link: https://lore.kernel.org/r/20210721155849.20994-18-kishon@ti.com

include/configs/j721e_evm.h

@@ -138,11 +138,24 @@
 #endif /* CONFIG_TARGET_J721E_A72_EVM */
 
 #ifdef CONFIG_TARGET_J7200_A72_EVM
+#define EXTRA_ENV_CONFIG_MAIN_CPSW0_QSGMII_PHY				\
+	"do_main_cpsw0_qsgmii_phyinit=1\0"				\
+	"init_main_cpsw0_qsgmii_phy=gpio set gpio@22_17;"		\
+		 "gpio clear gpio@22_16\0"				\
+	"main_cpsw0_qsgmii_phyinit="					\
+	"if test ${do_main_cpsw0_qsgmii_phyinit} -eq 1 && test ${dorprocboot} -eq 1 && " \
+			"test ${boot} = mmc; then "			\
+		"run init_main_cpsw0_qsgmii_phy;"			\
+	"fi;\0"
 #define DEFAULT_RPROCS ""						\
 		"2 /lib/firmware/j7200-main-r5f0_0-fw "			\
 		"3 /lib/firmware/j7200-main-r5f0_1-fw "
 #endif /* CONFIG_TARGET_J7200_A72_EVM */
 
+#ifndef EXTRA_ENV_CONFIG_MAIN_CPSW0_QSGMII_PHY
+#define EXTRA_ENV_CONFIG_MAIN_CPSW0_QSGMII_PHY
+#endif
+
 /* set default dfu_bufsiz to 128KB (sector size of OSPI) */
 #define EXTRA_ENV_DFUARGS \
 	"dfu_bufsiz=0x20000\0" \
@@ -190,6 +203,7 @@
 	EXTRA_ENV_DFUARGS						\
 	DEFAULT_UFS_TI_ARGS						\
 	EXTRA_ENV_J721E_BOARD_SETTINGS_MTD				\
+	EXTRA_ENV_CONFIG_MAIN_CPSW0_QSGMII_PHY				\
 	BOOTENV
 
 /* Now for the remaining common defines */