Add support for disabling 512B emulation

In this patch, we add a utility to disable emulation mode in eMMC-4.5.
This is done to increase the data sector size to 4KB.

Signed-off-by: Saugata Das <saugata.das@linaro.org>
Reviewed-by: Subhash Jadavani <subhashj@codeaurora.org>
Reviewed-by: Namjae Jeon <linkinjeon@gmail.com>
Reviewed-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
diff --git a/mmc.c b/mmc.c
index 6927b70..379d667 100644
--- a/mmc.c
+++ b/mmc.c
@@ -65,6 +65,11 @@
 		"Set the eMMC writeprotect status of <device>.",
 	  NULL
 	},
+	{ do_disable_512B_emulation, -1,
+	  "disable 512B emulation", "<device>\n"
+		"Set the eMMC data sector size to 4KB by disabling emulation on <device>.",
+	  NULL
+	},
 	{ do_write_boot_en, -3,
 	  "bootpart enable", "<boot_partition> " "<send_ack> " "<device>\n"
 		"Enable the boot partition for the <device>.\nTo receive acknowledgment of boot from the card set <send_ack>\nto 1, else set it to 0.",