From 871480933a1c28f8a9fed4c4d34d06c439a7a422 Mon Sep 17 00:00:00 2001
From: Srikant Patnaik
Date: Sun, 11 Jan 2015 12:28:04 +0530
Subject: Moved, renamed, and deleted files

The original directory structure was scattered and unorganized.
Changes are basically to make it look like kernel structure.
---
 Documentation/mmc/mmc-dev-parts.txt | 40 +++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)
 create mode 100644 Documentation/mmc/mmc-dev-parts.txt

(limited to 'Documentation/mmc/mmc-dev-parts.txt')

diff --git a/Documentation/mmc/mmc-dev-parts.txt b/Documentation/mmc/mmc-dev-parts.txt
new file mode 100644
index 00000000..f08d078d
--- /dev/null
+++ b/Documentation/mmc/mmc-dev-parts.txt
@@ -0,0 +1,40 @@
+SD and MMC Device Partitions
+============================
+
+Device partitions are additional logical block devices present on the
+SD/MMC device.
+
+As of this writing, MMC boot partitions as supported and exposed as
+/dev/mmcblkXboot0 and /dev/mmcblkXboot1, where X is the index of the
+parent /dev/mmcblkX.
+
+MMC Boot Partitions
+===================
+
+Read and write access is provided to the two MMC boot partitions. Due to
+the sensitive nature of the boot partition contents, which often store
+a bootloader or bootloader configuration tables crucial to booting the
+platform, write access is disabled by default to reduce the chance of
+accidental bricking.
+
+To enable write access to /dev/mmcblkXbootY, disable the forced read-only
+access with:
+
+echo 0 > /sys/block/mmcblkXbootY/force_ro
+
+To re-enable read-only access:
+
+echo 1 > /sys/block/mmcblkXbootY/force_ro
+
+The boot partitions can also be locked read only until the next power on,
+with:
+
+echo 1 > /sys/block/mmcblkXbootY/ro_lock_until_next_power_on
+
+This is a feature of the card and not of the kernel. If the card does
+not support boot partition locking, the file will not exist. If the
+feature has been disabled on the card, the file will be read-only.
+
+The boot partitions can also be locked permanently, but this feature is
+not accessible through sysfs in order to avoid accidental or malicious
+bricking.
-- 
cgit