Motorola LA-51XX, Руководство программиста драйвера

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SHoC Driver Design
The SHoC driver is designed for embedded systems. It works with the SHoC firmware running on an 802.11
device. The following sections describe the functionalities and components of the driver.
2.1 Initialization
After the device has been powered up, the driver is responsible for writing a firmware image into the device's
internal memory. Only after this firmware image has been loaded and started, subsequent communication
can take place.
For the driver, only the AHB-RAM memory is directly accessible, which has a size of 64KB. Since firmware
file is larger, it cannot be uploaded in a single step. It is therefore necessary to split the firmware into a
number of smaller blocks, and to have a simple program on the device, which accepts and disposes these
firmware blocks. The former is solved by the WRM file format; the latter is solved by the Upload Helper.
2.1.1 WRM file format
The WRM format is an array of n blocks, which must be parsed by the driver. Each block is uploaded
separately, and a simple set of rules are defined on how the driver should behave after a single block has
been uploaded. A common block consists of a header (blue) containing information for the driver, and a block
of data (white) opaque to the driver. The driver shall only upload the opaque data. The following illustration
shows a WRM block: