Changes between Version 29 and Version 30 of MMC

Timestamp:

06/08/2023 09:02:37 PM (2 years ago)

Author:

Tim Harvey

Comment:

moved U-Boot and Linux partition config under the partition config register details

MMC

@@ -43 +43 @@
 
 [=#emmc-partitions]
-=== eMMC Partitions ===
+=== eMMC Partitions
 eMMC devices are partitioned into several hardware partitions but only one can be selected at a time:
  - BOOT - one or more small partitions intended for boot firmware (eMMC 4.3 spec requires 2 boot and 1 user partition)
@@ -114 +114 @@
 
 Note that changing your eMMC partitioning differs a bit for each eMMC part (Manufacturer make and model) and needs to be done very early on as it can't succeed after a certain number of writes have occurred. If you need a specific partition configuration for a high volume product contact sales@gateworks.com for more info.
+
+[=#emmc-uboot]
+==== U-Boot Support
+U-Boot provides access to eMMC devices through the {{{mmc}}} command and interface but adds an additional argument to the {{{mmc}}} interface to describe the hardware partition. The interface is therefore described as 'mmc <dev> <part>' where 'dev' is the mmc device (some boards have more than one) and 'part' is the hardware partition: 0=user, 1=boot0, 2=boot1.
+
+Use the {{{mmc dev}}} command to specify the device and partition:
+{{{#!bash
+mmc dev 0 0 # select user hw partition
+mmc dev 0 1 # select boot0 hw partition
+mmc dev 0 2 # select boot1 hw partition
+}}}
+
+If U-Boot has been built with {{{CONFIG_SUPPORT_EMMC_BOOT}}} some additional mmc commands are available:
+ * mmc bootbus <dev> <boot_bus_width> <reset_boot_bus_width> <boot_mode>
+ * mmc bootpart-resize <dev> <boot-part-size-mb> <rpmb-part-size-mb>
+ * mmc partconf <dev> <boot_ack> <boot-partition> <partition-access> # set PARTITION_CONFIG field
+ * mmc rst-function <dev> <value> # change RST_n_FUNCTION field between 0|1|2 (write-once)
+
+The {{{mmc partconf}}} command can be used to configure the PARTITION_CONFIG specifying what hardware partition to boot from:
+{{{#!bash
+mmc partconf 0 0 0 0 # disable boot partition (default unset condition; boots from user partition)
+mmc partconf 0 1 1 0 # set boot0 partition (with ack)
+mmc partconf 0 1 2 0 # set boot1 partition (with ack)
+mmc partconf 0 1 7 0 # set user partition (with ack)
+}}}
+
+If U-Boot has been built with {{{CONFIG_SUPPORT_EMMC_RPMB}}} the {{{mmc rpmb}}} command is available for reading, writing and programming the key for the Replay Protection Memory Block (RPMB) partition in eMMC.
+
+When using U-Boot to write to eMMC (or microSD) it is often useful to use the {{{gzwrite}}} command. For example if you have a compressed 'disk image' you can write it to your eMMC (assuming it is mmc dev 0) with:
+{{{#!bash
+tftpboot ${loadaddr} disk-image.gz && gzwrite mmc 0 ${loadaddr} ${filesize}
+}}}
+ * The {{{disk-image.gz}}} contains a partition table at offset 0x0 as well as partitions at their respective offsets (according to the partition table) and has been compressed with gzip
+ * If you know the flash offset of a specific partition (which you can determine using the {{{part list mmc 0}}} command) you can also use gzwrite to flash a compressed partition image
+
+
+[=#emmc-linux]
+==== Linux Support
+Linux presents the various hardware partitions as separate devices:
+ - /dev/mmcblk0boot0 - BOOT0 partition
+ - /dev/mmcblk0boot1 - BOOT1 partition
+ - /dev/mmcblk0rpmb - RPMB partition
+ - /dev/mmcblk0 - USER partition
+
+Note that the BOOT partitions by default are read-only as they are typically used for sensitive boot firmware. To write to them you can disable {{{force_ro}}} in sysfs via:
+{{{#!bash
+echo 0 > /sys/class/block/mmcblk0boot0/force_ro
+}}}
+
+The Linux {{{mmc}}} application from the {{{mmc-utils}}} package provides access to eMMC configuration through CSD registers.
+
+You can use the {{{mmc}}} utility to configure the eMMC PARTITION_CONFIG to specify the boot device on power-up via {{{mmc bootpart enable <boot_partition> <send_ack> <device>}}} where boot_partition specifies the hardware partition (1=boot0, 2=boot1, 7=user), send_ack specifies the device must send an awknoledgement (for fast boot), and device is the root mmc block device of the eMMC:
+{{{#!bash
+# set boot partition to boot0
+mmc bootpart enable 1 0 /dev/mmcblk0
+# set boot partition to boot1
+mmc bootpart enable 2 0 /dev/mmcblk0
+# set boot partition to user
+mmc bootpart enable 7 0 /dev/mmcblk0
+}}}
+
+Some additional use cases:
+{{{#!bash
+# show PARTITION_CONFIG:
+mmc extcsd read /dev/mmcblk0 | grep PARTITION_CONFIG
+# show BUS CONFIG:
+mmc extcsd read /dev/mmcblk0 | grep BOOT_BUS_CONDITIONS
+# disable boot partition
+mmc bootpart enable 0 0 /dev/mmcblk0
+}}}
+
+References:
+ * https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/mmc/mmc-tools.txt
+
 
 [=#emmc-enhanced-user-area]
@@ -240 +314 @@
 - if you change the configuration of your boot area you must re-program the eMMC via JTAG
 
-[=#emmc-uboot]
-=== U-Boot Support ===
-U-Boot provides access to eMMC devices through the {{{mmc}}} command and interface but adds an additional argument to the {{{mmc}}} interface to describe the hardware partition. The interface is therefore described as 'mmc <dev> <part>' where 'dev' is the mmc device (some boards have more than one) and 'part' is the hardware partition: 0=user, 1=boot0, 2=boot1.
-
-Use the {{{mmc dev}}} command to specify the device and partition:
-{{{#!bash
-mmc dev 0 0 # select user hw partition
-mmc dev 0 1 # select boot0 hw partition
-mmc dev 0 2 # select boot1 hw partition
-}}}
-
-If U-Boot has been built with {{{CONFIG_SUPPORT_EMMC_BOOT}}} some additional mmc commands are available:
- * mmc bootbus <dev> <boot_bus_width> <reset_boot_bus_width> <boot_mode>
- * mmc bootpart-resize <dev> <boot-part-size-mb> <rpmb-part-size-mb>
- * mmc partconf <dev> <boot_ack> <boot-partition> <partition-access> # set PARTITION_CONFIG field
- * mmc rst-function <dev> <value> # change RST_n_FUNCTION field between 0|1|2 (write-once)
-
-The {{{mmc partconf}}} command can be used to configure the PARTITION_CONFIG specifying what hardware partition to boot from:
-{{{#!bash
-mmc partconf 0 0 0 0 # disable boot partition (default unset condition; boots from user partition)
-mmc partconf 0 1 1 0 # set boot0 partition (with ack)
-mmc partconf 0 1 2 0 # set boot1 partition (with ack)
-mmc partconf 0 1 7 0 # set user partition (with ack)
-}}}
-
-If U-Boot has been built with {{{CONFIG_SUPPORT_EMMC_RPMB}}} the {{{mmc rpmb}}} command is available for reading, writing and programming the key for the Replay Protection Memory Block (RPMB) partition in eMMC.
-
-When using U-Boot to write to eMMC (or microSD) it is often useful to use the {{{gzwrite}}} command. For example if you have a compressed 'disk image' you can write it to your eMMC (assuming it is mmc dev 0) with:
-{{{#!bash
-tftpboot ${loadaddr} disk-image.gz && gzwrite mmc 0 ${loadaddr} ${filesize}
-}}}
- * The {{{disk-image.gz}}} contains a partition table at offset 0x0 as well as partitions at their respective offsets (according to the partition table) and has been compressed with gzip
- * If you know the flash offset of a specific partition (which you can determine using the {{{part list mmc 0}}} command) you can also use gzwrite to flash a compressed partition image
-
-
-[=#emmc-linux]
-=== Linux Support ===
-Linux presents the various hardware partitions as separate devices:
- - /dev/mmcblk0boot0 - BOOT0 partition
- - /dev/mmcblk0boot1 - BOOT1 partition
- - /dev/mmcblk0rpmb - RPMB partition
- - /dev/mmcblk0 - USER partition
-
-Note that the BOOT partitions by default are read-only as they are typically used for sensitive boot firmware. To write to them you can disable {{{force_ro}}} in sysfs via:
-{{{#!bash
-echo 0 > /sys/class/block/mmcblk0boot0/force_ro
-}}}
-
-The Linux {{{mmc}}} application from the {{{mmc-utils}}} package provides access to eMMC configuration through CSD registers.
-
-You can use the {{{mmc}}} utility to configure the eMMC PARTITION_CONFIG to specify the boot device on power-up via {{{mmc bootpart enable <boot_partition> <send_ack> <device>}}} where boot_partition specifies the hardware partition (1=boot0, 2=boot1, 7=user), send_ack specifies the device must send an awknoledgement (for fast boot), and device is the root mmc block device of the eMMC:
-{{{#!bash
-# set boot partition to boot0
-mmc bootpart enable 1 0 /dev/mmcblk0
-# set boot partition to boot1
-mmc bootpart enable 2 0 /dev/mmcblk0
-# set boot partition to user
-mmc bootpart enable 7 0 /dev/mmcblk0
-}}}
-
-Some additional use cases:
-{{{#!bash
-# show PARTITION_CONFIG:
-mmc extcsd read /dev/mmcblk0 | grep PARTITION_CONFIG
-# show BUS CONFIG:
-mmc extcsd read /dev/mmcblk0 | grep BOOT_BUS_CONDITIONS
-# disable boot partition
-mmc bootpart enable 0 0 /dev/mmcblk0
-}}}
-
-References:
- * https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/mmc/mmc-tools.txt
-
 
 [=#microsd]