fastboot: add command to select the default emmc hwpart for boot

Add fastboot command oem partconf which executes the command
``mmc partconf <id> <arg> 0`` on the current <id> mmc device
to configure the eMMC boot partition with
<arg>: boot_ack boot_partition, so the command is:

$> fastboot oem partconf:<boot_ack> <boot_partition>

The partition_access argument is forced to 0 (userdata)

Signed-off-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
[lukma - Kconfig adjustments after merging this patch]

doc/android/fastboot.rst

@@ -23,6 +23,8 @@ The current implementation supports the following standard commands:
 The following OEM commands are supported (if enabled):
 
 - ``oem format`` - this executes ``gpt write mmc %x $partitions``
+- ``oem partconf`` - this executes ``mmc partconf %x <arg> 0`` to configure eMMC
+  with <arg> = boot_ack boot_partition
 
 Support for both eMMC and NAND devices is included.
 

drivers/fastboot/Kconfig

@@ -189,6 +189,13 @@ config FASTBOOT_CMD_OEM_FORMAT
 	  relies on the env variable partitions to contain the list of
 	  partitions as required by the gpt command.
 
+config FASTBOOT_CMD_OEM_PARTCONF
+	bool "Enable the 'oem partconf' command"
+	depends on FASTBOOT_FLASH_MMC && SUPPORT_EMMC_BOOT
+	help
+	  Add support for the "oem partconf" command from a client. This set
+	  the mmc boot-partition for the selecting eMMC device.
+
 endif # FASTBOOT
 
 endmenu

drivers/fastboot/fb_command.c

@@ -42,6 +42,9 @@ static void reboot_recovery(char *, char *);
 #if CONFIG_IS_ENABLED(FASTBOOT_CMD_OEM_FORMAT)
 static void oem_format(char *, char *);
 #endif
+#if CONFIG_IS_ENABLED(FASTBOOT_CMD_OEM_PARTCONF)
+static void oem_partconf(char *, char *);
+#endif
 
 static const struct {
 	const char *command;
@@ -99,6 +102,12 @@ static const struct {
 		.dispatch = oem_format,
 	},
 #endif
+#if CONFIG_IS_ENABLED(FASTBOOT_CMD_OEM_PARTCONF)
+	[FASTBOOT_COMMAND_OEM_PARTCONF] = {
+		.command = "oem partconf",
+		.dispatch = oem_partconf,
+	},
+#endif
 };
 
 /**
@@ -374,3 +383,30 @@ static void oem_format(char *cmd_parameter, char *response)
 	}
 }
 #endif
+
+#if CONFIG_IS_ENABLED(FASTBOOT_CMD_OEM_PARTCONF)
+/**
+ * oem_partconf() - Execute the OEM partconf command
+ *
+ * @cmd_parameter: Pointer to command parameter
+ * @response: Pointer to fastboot response buffer
+ */
+static void oem_partconf(char *cmd_parameter, char *response)
+{
+	char cmdbuf[32];
+
+	if (!cmd_parameter) {
+		fastboot_fail("Expected command parameter", response);
+		return;
+	}
+
+	/* execute 'mmc partconfg' command with cmd_parameter arguments*/
+	snprintf(cmdbuf, sizeof(cmdbuf), "mmc partconf %x %s 0",
+		 CONFIG_FASTBOOT_FLASH_MMC_DEV, cmd_parameter);
+	printf("Execute: %s\n", cmdbuf);
+	if (run_command(cmdbuf, 0))
+		fastboot_fail("Cannot set oem partconf", response);
+	else
+		fastboot_okay(NULL, response);
+}
+#endif

include/fastboot.h

@@ -38,6 +38,9 @@ enum {
 #if CONFIG_IS_ENABLED(FASTBOOT_CMD_OEM_FORMAT)
 	FASTBOOT_COMMAND_OEM_FORMAT,
 #endif
+#if CONFIG_IS_ENABLED(FASTBOOT_CMD_OEM_PARTCONF)
+	FASTBOOT_COMMAND_OEM_PARTCONF,
+#endif
 
 	FASTBOOT_COMMAND_COUNT
 };