docs: update partition tables documentation

This commit is contained in:
Ivan Grokhotkov 2016-11-18 20:34:54 +08:00
parent 0b265dc2a7
commit 1f6585dd4f

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@ -17,40 +17,30 @@ The simplest way to use the partition table is to `make menuconfig` and choose o
In both cases the factory app is flashed at offset 0x10000. If you `make partition_table` then it will print a summary of the partition table.
Known Issues
------------
The below design document outlines the goals for the partition table system. At the moment, only some features are used:
- data partition types "rf" & "wifi" are unused and can be entirely omitted to save space.
- NVS (non-volatile-storage) uses a hardcoded 12KB (0x3000 byte) region at offset 0x9000.
Once a full user API is in place for partition access, these limitations will be resolved and you'll be able to use the partition mechanism fully for storing data in flash.
Built-in Partition Tables
-------------------------
Here is the summary printed for the "Single factory app, no OTA" configuration::
# Espressif ESP32 Partition Table
# Name, Type, SubType, Offset, Size
factory, app, factory, 0x10000, 1M
rfdata, data, rf, 0x110000, 256K
wifidata,data, wifi, 0x150000, 256K
# Name, Type, SubType, Offset, Size
nvs, data, nvs, 0x9000, 0x6000
phy_init, data, phy, 0xf000, 0x1000
factory, app, factory, 0x10000, 1M
* At a 0x10000 (64KB) offset in the flash is the app labelled "factory". The bootloader will run this app by default.
* There are also two data regions defined in the partition table for storing RF & Wifi calibration data.
* There are also two data regions defined in the partition table for storing NVS library partition and PHY init data.
Here is the summary printed for the "Factory app, two OTA definitions" configuration::
# Espressif ESP32 Partition Table
# Name, Type, SubType, Offset, Size
factory, app, factory, 0x10000, 1M
ota_0, app, ota_0, 0x110000, 1M
ota_1, app, ota_1, 0x210000, 1M
rfdata, data, rf, 0x310000, 256K
wifidata,data, wifi, 0x350000, 256K
otadata, data, ota, 0x390000, 256K
# Name, Type, SubType, Offset, Size
nvs, data, nvs, 0x9000, 0x4000
otadata, data, ota, 0xd000, 0x2000
phy_init, data, phy, 0xf000, 0x1000
factory, 0, 0, 0x10000, 1M
ota_0, 0, ota_0, , 1M
ota_1, 0, ota_1, , 1M
* There are now three app partition definitions.
* The type of all three are set as "app", but the subtype varies between the factory app at 0x10000 and the next two "OTA" apps.
@ -65,13 +55,13 @@ If you choose "Custom partition table CSV" in menuconfig then you can also enter
The CSV format is the same format as printed in the summaries shown above. However, not all fields are required in the CSV. For example, here is the "input" CSV for the OTA partition table::
# Name, Type, SubType, Offset, Size
nvs, data, nvs, 0x9000, 0x4000
otadata, data, ota, 0xd000, 0x2000
phy_init, data, phy, 0xf000, 0x1000
factory, app, factory, 0x10000, 1M
ota_0, app, ota_0, , 1M
ota_1, app, ota_1, , 1M
rfdata, data, rf, , 256K
wifidata, data, wifi, , 256K
otadata, data, ota, , 256K
* Whitespace between fields is ignored, and so is any line starting with # (comments).
* Each non-comment line in the CSV file is a partition definition.
* Only the offset for the first partition is supplied. The gen_esp32part.py tool fills in each remaining offset to start after the preceding partition.
@ -93,7 +83,7 @@ Subtype
When type is "app", the subtype field can be specified as factory (0), ota_0 (0x10) ... ota_15 (0x1F) and test (0x20). Or it can be any number 0-255 (0x00-0xFF). The bootloader will execute the factory app unless there it sees a partition of type data/ota, in which case it reads this partition to determine which OTA image to boot
When type is "data", the subtype field can be specified as ota (0), rf (1), wifi (2). Or it can be a number 0x00-0xFF. The bootloader ignores all data subtypes except for ota. Other "data" subtypes are reserved for Espressif use. To create custom data partition subtypes then use a custom type value, and choose any subtype 0x00-0xFF.
When type is "data", the subtype field can be specified as ota (0), phy (1), nvs (2). Or it can be a number 0x00-0xFF. The bootloader ignores all data subtypes except for ota. Subtypes 0-0x7f are reserved for Espressif use. To create custom data partition subtypes use "data" type, and choose any unused subtype in 0x80-0xFF range. If you are porting a filesystem to the ESP-IDF, consider opening a PR to add the new subtype to esp_partition.h file.
Offset & Size
~~~~~~~~~~~~~
@ -104,6 +94,8 @@ App partitions have to be at offsets aligned to 0x10000 (64K). If you leave the
Sizes and offsets can be specified as decimal numbers, hex numbers with the prefix 0x, or size multipliers M or K (1024 and 1024*1024 bytes).
NVS data partition has to be at least 0x3000 bytes long, and OTA data parition has to be 0x2000 bytes long. If you are using NVS in your application to store a lot of data, consider using a custom partition table with larger NVS partition.
Generating Binary Partition Table
---------------------------------