[PATCH] doc: mmc man-page

Heinrich Schuchardt xypron.glpk at gmx.de
Tue Mar 30 12:39:20 CEST 2021


On 3/30/21 1:29 AM, Jaehoon Chung wrote:
> Provide a man-pages for the mmc command.
>
> Signed-off-by: Jaehoon Chung <jh80.chung at samsung.com>
> ---
>   doc/usage/index.rst |   1 +
>   doc/usage/mmc.rst   | 182 ++++++++++++++++++++++++++++++++++++++++++++
>   2 files changed, 183 insertions(+)
>   create mode 100644 doc/usage/mmc.rst
>
> diff --git a/doc/usage/index.rst b/doc/usage/index.rst
> index 6c59bbadab45..15c682ceface 100644
> --- a/doc/usage/index.rst
> +++ b/doc/usage/index.rst
> @@ -30,6 +30,7 @@ Shell commands
>      load
>      loady
>      mbr
> +   mmc
>      pstore
>      qfw
>      sbi
> diff --git a/doc/usage/mmc.rst b/doc/usage/mmc.rst
> new file mode 100644
> index 000000000000..00a21a6e12e7
> --- /dev/null
> +++ b/doc/usage/mmc.rst
> @@ -0,0 +1,182 @@
> +.. SPDX-License-Identifier: GPL-2.0+:
> +
> +mmc command
> +============
> +
> +Synopsis
> +--------
> +
> +::
> +
> +    mmc info
> +    mmc read addr blk# cnt
> +    mmc write addr blk# cnt
> +    mmc erase blk# cnt
> +    mmc rescan
> +    mmc part
> +    mmc dev [dev] [part]
> +    mmc list
> +    mmc wp
> +    mmc bootbus <dev> <boot_bus_width> <reset_boot_bus_width> <boot_mode>
> +    mmc bootpart-resize <dev> <dev part size MB> <RPMB part size MB>
> +    mmc partconf <dev> [boot_ack boot_partition partition_access]
> +    mmc rst-function <dev> <value>
> +
> +Description
> +-----------
> +
> +The mmc command is used to control MMC(eMMC/SD) device.
> +
> +The *mmc info* command displays information (Manufacturer ID, OEM, Name, Bus Speed, Mode, ...) of MMC device.
> +
> +The *mmc read* command reads raw data to memory address from MMC device with block offset and count.
> +
> +The *mmc write* command writes raw data to MMC device from memory address with block offset and count.

Thank you for providing this man-page.

Not having an empty line here makes the line above bold. Please, avoid
inconsistent formatting by adding an empty line.

Please, inspect the rendered page in a browser.

> +    addr
> +        memory address
> +    blk#
> +        start block offset
> +    cnt
> +        block count
> +
> +The *mmc erase* command erases MMC device from block offset until count.

missing empty line

> +    blk#
> +        start block offset
> +    cnt
> +        block count
> +
> +The *mmc rescan* command scans the available MMC device.
> +
> +The *mmc part* command displays the list available partition on current mmc device.
> +
> +The *mmc dev* command shows or set current mmc device.

missing empty line

> +    dev
> +        device number to change
> +    part
> +        partition number to change
> +
> +The *mmc list* command displays the list available devices.
> +
> +The *mmc wp* command enables "power on write protect" function for boot partitions.
> +
> +The *mmc bootbus* command sets the BOOT_BUS_WIDTH field.
> +    BOOTU_BUS_WIDTH[177] is one of EXT_CSD register. (*Refer to eMMC specification*)

This line should not be indented.

> +
> +The *mmc partconf* command shows or changes PARTITION_CONFIG field.

missing empty line

> +    boot_ack
> +        boot acknowledge value
> +    boot_partition
> +        boot partition to enable for boot
> +            0x0
> +                Device not boot enabled(default)
> +            0x1
> +                Boot partition1 enabled for boot
> +            0x2
> +                Boot partition2 enabled for boot
> +            0x7
> +                User area enabled for boot
> +            others
> +                Reserved
> +    partition_access
> +        partitions to access
> +
> +The *mmc-bootpart-resize* command changes sizes of boot and RPMB partitions.
> +    dev
> +        device number
> +    boot part size MB
> +        target size of boot partition
> +    RPMB part size MB
> +        target size of RPMB partition
> +
> +The *mmc rst-function* command changes the RST_n_FUNCTION field.
> +    **WARNING**: This is a write-once field. (*Refer to eMMC specification*)

This line should not be indented.

> +        RST_n_FUNCTION[162] is one of EXT_CSD register. (Readable and Writable once)

How is this line related to the mmc command?

> +            0x0

'value' is missing here to make it clear which parameter these numbers
relate to.

> +                RST_n signal is temporarily disabled (default)
> +            0x1
> +                RST_n signal is permanently enabled
> +            0x2
> +                RST_n signal is permanently disabled
> +            0x3
> +                Reserved
> +
> +
> +Example

Examples

Best regards

Heinrich

> +-------
> +
> +The *mmc info* command displays device's capabilities:
> +::
> +
> +    => mmc info
> +    Device: EXYNOS DWMMC
> +    Manufacturer ID: 45
> +    OEM: 100
> +    Name: SDW16
> +    Bus Speed: 52000000
> +    Mode: MMC DDR52 (52MHz)
> +    Rd Block Len: 512
> +    MMC version 5.0
> +    High Capacity: Yes
> +    Capacity: 14.7 GiB
> +    Bus Width: 8-bit DDR
> +    Erase Group Size: 512 KiB
> +    HC WP Group Size: 8 MiB
> +    User Capacity: 14.7 GiB WRREL
> +    Boot Capacity: 4 MiB ENH
> +    RPMB Capacity: 4 MiB ENH
> +    Boot area 0 is not write protected
> +    Boot area 1 is not write protected
> +
> +The raw data can be read/written via *mmc read/write* command:
> +::
> +
> +    => mmc read 0x40000000 0x5000 0x100
> +    MMC read: dev # 0, block # 20480, count 256 ... 256 blocks read: OK
> +
> +    => mmc write 0x40000000 0x5000 0x10
> +    MMC write: dev # 0, block # 20480, count 256 ... 256 blocks written: OK
> +
> +The partition list can be shown via *mmc part* command:
> +::
> +
> +    => mmc part
> +    Partition Map for MMC device 0  --   Partition Type: DOS
> +
> +    Part    Start Sector    Num Sectors     UUID            Type
> +      1     8192            131072          dff8751a-01     0e Boot
> +      2     139264          6291456         dff8751a-02     83
> +      3     6430720         1048576         dff8751a-03     83
> +      4     7479296         23298048        dff8751a-04     05 Extd
> +      5     7481344         307200          dff8751a-05     83
> +      6     7790592         65536           dff8751a-06     83
> +      7     7858176         16384           dff8751a-07     83
> +      8     7876608         22900736        dff8751a-08     83
> +
> +The current device can be shown or set via *mmc dev* command:
> +::
> +
> +    => mmc dev
> +    switch to partitions #0, OK
> +    mmc0(part0) is current device
> +    => mmc dev 2 0
> +    switch to partitions #0, OK
> +    mmc2 is current device
> +
> +The list of available devices can be shown via *mmc list* command:
> +::
> +
> +    => mmc list
> +    mmc list
> +    EXYNOS DWMMC: 0 (eMMC)
> +    EXYNOS DWMMC: 2 (SD)
> +
> +Configuration
> +-------------
> +
> +The mmc command is only available if CONFIG_CMD_MMC=y.
> +Some commands need to enable more configuration.
> +
> +write, erase
> +    CONFIG_MMC_WRITE
> +bootbus, bootpart-resize, partconf, rst-function
> +    CONFIG_SUPPORT_EMMC_BOOT=y
>



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