serial: sh: Add RZ/G2L SCIF support

Extend the existing driver to support the SCIF serial ports on the
Renesas RZ/G2L (R9A07G044) SoC. This also requires us to ensure that if
there is a reset signal defined in the device tree, it is de-asserted
before we try to talk to the SCIF module.

Signed-off-by: Paul Barker <paul.barker.ct@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Tested-by: Marek Vasut <marek.vasut+renesas@mailbox.org> # R-Car H3 Salvator-XS
diff --git a/drivers/serial/serial_sh.h b/drivers/serial/serial_sh.h
index 149ec1f..58c2d22 100644
--- a/drivers/serial/serial_sh.h
+++ b/drivers/serial/serial_sh.h
@@ -90,7 +90,7 @@
 # define SCSCR_INIT(port)	0x38 /* TIE=0,RIE=0,TE=1,RE=1,REIE=1 */
 # define SCIF_ORER 0x0001  /* overrun error bit */
 #elif defined(CONFIG_RCAR_GEN2) || defined(CONFIG_RCAR_64) || \
-      defined(CONFIG_R7S72100)
+      defined(CONFIG_R7S72100) || defined(CONFIG_RZG2L)
 # if defined(CFG_SCIF_A)
 #  define SCIF_ORER	0x0200
 # else
@@ -312,6 +312,9 @@
 					sh4_scif_offset, sh4_scif_size)
 		#define SCIF_FNS(name, sh4_scif_offset, sh4_scif_size) \
 			CPU_SCIF_FNS(name, sh4_scif_offset, sh4_scif_size)
+#elif defined(CONFIG_RZG2L)
+#define SCIF_FNS(reg_name, reg_offset, reg_size) \
+	CPU_SCIF_FNS(reg_name, reg_offset, reg_size)
 #else
 #define SCIx_FNS(name, sh3_sci_offset, sh3_sci_size,\
 				sh4_sci_offset, sh4_sci_size, \
@@ -387,6 +390,20 @@
 #else
 SCIF_FNS(SCLSR,  0,  0, 0x24, 16)
 #endif
+#elif defined(CONFIG_RZG2L)
+SCIF_FNS(SCSMR,  0x00, 16)
+SCIF_FNS(SCBRR,  0x02,  8)
+SCIF_FNS(SCSCR,  0x04, 16)
+SCIF_FNS(SCxTDR, 0x06,  8)
+SCIF_FNS(SCxSR,  0x08, 16)
+SCIF_FNS(SCxRDR, 0x0A,  8)
+SCIF_FNS(SCFCR,  0x0C, 16)
+SCIF_FNS(SCFDR,  0x0E, 16)
+SCIF_FNS(SCSPTR, 0x10, 16)
+SCIF_FNS(SCLSR,  0x12, 16)
+SCIF_FNS(SCSEMR, 0x14,  8)
+SCIF_FNS(SCxTCR, 0x16, 16)
+SCIF_FNS(DL,     0x00,  0)
 #else
 /*      reg      SCI/SH3   SCI/SH4  SCIF/SH3   SCIF/SH4  SCI/H8*/
 /*      name     off  sz   off  sz   off  sz   off  sz   off  sz*/