Intel 82558 Manuale Utente

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The initialization code can be broadly split in the following code modules:

•

8255x initialization

•

PHY detection and initialization

•

NOS specific initialization

The sample source code provides specific coding examples. A list of programming issues to 
consider is listed in the following subsections by code module.

•

The device is internally fully reset on power up. However, the adapter and the 8255x are not 
fully reset after a warm reboot. Thus, it is recommended that the software issues a Port 

Software Reset command before accessing the device. 
Note:

All Port commands cause a complete internal reset requiring software to re-
initialize the device.

•

The interrupt mask bit (SCB Command word, Mask bit) is set to 0 after a complete reset, 

implying that interrupts are enabled. It is software responsibility to ensure that this bit is set to 
disable interrupts after a Port command is issued and before polled mode commands are 

executed.

•

If promiscuous mode is enabled, the following Configure command bits are also affected:

— SAVE BAD FRAMES. This feature should be enabled.

— DISCARD SHORT FRAMES. This feature should be disabled.

— PADDING. This feature should be disabled.

— STRIPPING. This feature should be disabled.

•

It is recommended that all non-transmit action commands are executed in polled mode. 
Software should maintain a single list of transmit CBs and modify a CB to a non-transmit CB 

when required. The 8255x supports dynamic CU Resume commands on non-transmit 

commands; therefore, no checks are required before such a command is issued.

It is recommended that drivers support the Intel

®

 82503 and 82555 and the National 

Semiconductor* DP83840 devices as well as the integrated PHY units of the 82558, 82559, 82550, 
and 82551. In addition, a vendor specific routine should be executed immediately after PHY 

detection to initialize specific registers in other third party PHYs (for example, the DP83840).