[PATCH v4 2/2] doc: usage: mmc: Document usage of speed mode in "mmc dev" and "mmc rescan"
Aswath Govindraju
a-govindraju at ti.com
Fri Aug 13 19:34:42 CEST 2021
Add documentation on the usage of "mmc dev" and "mmc rescan" commands to
set user defined speed modes.
Signed-off-by: Aswath Govindraju <a-govindraju at ti.com>
---
doc/usage/mmc.rst | 49 +++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 47 insertions(+), 2 deletions(-)
diff --git a/doc/usage/mmc.rst b/doc/usage/mmc.rst
index f20efe3d7063..d15b151884fd 100644
--- a/doc/usage/mmc.rst
+++ b/doc/usage/mmc.rst
@@ -12,9 +12,9 @@ Synopsis
mmc read addr blk# cnt
mmc write addr blk# cnt
mmc erase blk# cnt
- mmc rescan
+ mmc rescan [mode]
mmc part
- mmc dev [dev] [part]
+ mmc dev [dev] [part] [mode]
mmc list
mmc wp
mmc bootbus <dev> <boot_bus_width> <reset_boot_bus_width> <boot_mode>
@@ -49,6 +49,27 @@ The 'mmc erase' command erases *cnt* blocks on the MMC device starting at block
The 'mmc rescan' command scans the available MMC device.
+ mode
+ speed mode to set.
+ CONFIG_MMC_SPEED_MODE_SET should be enabled. The required speed mode is
+ passed as the index from the following list.
+
+ 0 - MMC_LEGACY
+ 1 - MMC_HS
+ 2 - SD_HS
+ 3 - MMC_HS_52
+ 4 - MMC_DDR_52
+ 5 - UHS_SDR12
+ 6 - UHS_SDR25
+ 7 - UHS_SDR50
+ 8 - UHS_DDR50
+ 9 - UHS_SDR104
+ 10 - MMC_HS_200
+ 11 - MMC_HS_400
+ 12 - MMC_HS_400_ES
+
+ A speed mode can be set only if it has already been enabled in the device tree
+
The 'mmc part' command displays the list available partition on current mmc device.
The 'mmc dev' command shows or set current mmc device.
@@ -58,6 +79,27 @@ The 'mmc dev' command shows or set current mmc device.
part
partition number to change
+ mode
+ speed mode to set.
+ CONFIG_MMC_SPEED_MODE_SET should be enabled. The required speed mode is
+ passed as the index from the following list.
+
+ 0 - MMC_LEGACY
+ 1 - MMC_HS
+ 2 - SD_HS
+ 3 - MMC_HS_52
+ 4 - MMC_DDR_52
+ 5 - UHS_SDR12
+ 6 - UHS_SDR25
+ 7 - UHS_SDR50
+ 8 - UHS_DDR50
+ 9 - UHS_SDR104
+ 10 - MMC_HS_200
+ 11 - MMC_HS_400
+ 12 - MMC_HS_400_ES
+
+ A speed mode can be set only if it has already been enabled in the device tree
+
The 'mmc list' command displays the list available devices.
The 'mmc wp' command enables "power on write protect" function for boot partitions.
@@ -194,6 +236,9 @@ The current device can be shown or set via 'mmc dev' command:
=> mmc dev 2 0
switch to partitions #0, OK
mmc2 is current device
+ => mmc dev 0 1 4
+ switch to partitions #1, OK
+ mmc0(part 1) is current device
The list of available devices can be shown via 'mmc list' command:
::
--
2.17.1
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