env: ti: k3_rproc: Add common rproc environment variables

Add a new file include/environment/ti/k3_rproc.h that defines
common environment variables useful for booting various remote
processors from U-Boot. This file is expected to be included in
the board config files with the EXTRA_ENV_RPROC_SETTINGS added
to CONFIG_EXTRA_ENV_SETTINGS and DEFAULT_RPROCS macro overwritten
to include the actual list of processors to be booted.

The 'boot_rprocs' variable just needs to be added to the board's
bootcmd to automatically boot the processors, and runtime control
can be achieved through the 'dorprocboot' variable.

The variables are currently defined to use MMC as the boot media,
and can be expanded in the future to include other boot media.
The immediate usage is intended for K3 J721E SoCs.
Signed-off-by: NJean-Jacques Hiblot <jjhiblot@ti.com>
Signed-off-by: NSuman Anna <s-anna@ti.com>

include/environment/ti/k3_rproc.h

+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com
+ *
+ * rproc environment variable definitions for various TI K3 SoCs.
+ */
+
+#ifndef __TI_RPROC_H
+#define __TI_RPROC_H
+
+/*
+ * should contain a list of <rproc_id fw_name> tuplies,
+ * override in board config files with the actual list
+ */
+#define DEFAULT_RPROCS ""
+
+#ifdef CONFIG_CMD_REMOTEPROC
+#define EXTRA_ENV_RPROC_SETTINGS					\
+	"dorprocboot=0\0"						\
+	"boot_rprocs="							\
+		"if test ${dorprocboot} -eq 1 && test ${boot} = mmc; then "\
+			"rproc init;"					\
+			"run boot_rprocs_mmc;"				\
+		"fi;\0"							\
+	"rproc_load_and_boot_one="					\
+		"if load mmc ${bootpart} $loadaddr ${rproc_fw}; then "	\
+			"if rproc load ${rproc_id} ${loadaddr} ${filesize}; then "\
+				"rproc start ${rproc_id};"		\
+			"fi;"						\
+		"fi\0"							\
+	"boot_rprocs_mmc="						\
+		"env set rproc_id;"					\
+		"env set rproc_fw;"					\
+		"for i in ${rproc_fw_binaries} ; do "			\
+			"if test -z \"${rproc_id}\" ; then "		\
+				"env set rproc_id $i;"			\
+			"else "						\
+				"env set rproc_fw $i;"			\
+				"run rproc_load_and_boot_one;"		\
+				"env set rproc_id;"			\
+				"env set rproc_fw;"			\
+			"fi;"						\
+		"done\0"						\
+	"rproc_fw_binaries="						\
+		DEFAULT_RPROCS						\
+		"\0"
+#else
+#define EXTRA_ENV_RPROC_SETTINGS					\
+	"boot_rprocs= \0"
+#endif /* CONFIG_CMD_REMOTEPROC */
+
+#endif /* __TI_RPROC_H */