configs: am335x_evm: Support distro bootcmds

Add support for distro bootcmds and network booting while retaining
backwards compatibility with the current "legacy" setup. With these
changes the default boot sequence becomes:

* SD card (standard distro boot)
* SD card (legacy boot)
* EMMC (standard distro boot)
* EMMC (legacy boot)
* Nand (legacy boot)
* PXE (standard distro boot)
* DHCP (standard distro boot)

The older boot scripts have some overlap with what the distro
bootcommands to however i've left them unchanged to prevent introduction
of subtle bugs.

Signed-off-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk>

include/configs/am335x_evm.h

@@ -18,6 +18,10 @@
 
 #include <configs/ti_am335x_common.h>
 
+/* Don't override the distro default bootdelay */
+#undef CONFIG_BOOTDELAY
+#include <config_distro_defaults.h>
+
 #ifndef CONFIG_SPL_BUILD
 #ifndef CONFIG_FIT
 # define CONFIG_FIT
@@ -67,6 +71,37 @@
 
 #define CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
 
+#define BOOTENV_DEV_LEGACY_MMC(devtypeu, devtypel, instance) \
+	"bootcmd_" #devtypel #instance "=" \
+	"setenv mmcdev " #instance"; "\
+	"setenv bootpart " #instance":2 ; "\
+	"run mmcboot\0"
+
+#define BOOTENV_DEV_NAME_LEGACY_MMC(devtypeu, devtypel, instance) \
+	#devtypel #instance " "
+
+#define BOOTENV_DEV_NAND(devtypeu, devtypel, instance) \
+	"bootcmd_" #devtypel "=" \
+	"run nandboot\0"
+
+#define BOOTENV_DEV_NAME_NAND(devtypeu, devtypel, instance) \
+	#devtypel #instance " "
+
+#define BOOT_TARGET_DEVICES(func) \
+	func(MMC, mmc, 0) \
+	func(LEGACY_MMC, legacy_mmc, 0) \
+	func(MMC, mmc, 1) \
+	func(LEGACY_MMC, legacy_mmc, 1) \
+	func(NAND, nand, 0) \
+	func(PXE, pxe, na) \
+	func(DHCP, dhcp, na)
+
+#define CONFIG_BOOTCOMMAND \
+	"run findfdt; " \
+	"run distro_bootcmd"
+
+#include <config_distro_bootcmd.h>
+
 #ifndef CONFIG_SPL_BUILD
 #define CONFIG_EXTRA_ENV_SETTINGS \
 	DEFAULT_LINUX_BOOT_ENV \
@@ -160,16 +195,10 @@
 			"echo WARNING: Could not determine device tree to use; fi; \0" \
 	NANDARGS \
 	NETARGS \
-	DFUARGS
+	DFUARGS \
+	BOOTENV
 #endif
 
-#define CONFIG_BOOTCOMMAND \
-	"run findfdt; " \
-	"run mmcboot;" \
-	"setenv mmcdev 1; " \
-	"setenv bootpart 1:2; " \
-	"run mmcboot;" \
-	"run nandboot;"
 
 /* NS16550 Configuration */
 #define CONFIG_SYS_NS16550_COM1		0x44e09000	/* Base EVM has UART0 */