Difference between revisions of "Developer Manual/Super IO"

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Some Super I/O's use register 0x30 of one of the logical device numbers (LDN) to also enable other logical device's functions.
Some Super I/O's use register 0x30 of one of the logical device numbers (LDN) to also enable other logical device's functions.
For example, in the case of the W83627EHF chip, register 0x30 of LDN 0x9 was used to enable multiple devices (GPIO2 = bit0, GPIO3 = bit1, GPIO4 = bit2 and GPIO5 = bit3). To overcome this issue a concept of virtual LDN has been [https://www.coreboot.org/pipermail/coreboot/2008-February/030912.html introduced].
For example, in the case of the [http://media.digikey.com/pdf/Data%20Sheets/Nuvoton%20PDFs/W83627EHx_EG_EFc.pdf W83627EHF chip], register 0x30 of LDN 0x9 was used to enable multiple devices (GPIO2 = bit0, GPIO3 = bit1, GPIO4 = bit2 and GPIO5 = bit3). To overcome this issue a concept of virtual LDN has been [https://www.coreboot.org/pipermail/coreboot/2008-February/030912.html introduced].


Virtual LDN's can be used in Coreboot to uniquely map the enable bit position in register 0x30 of an LDN, this allows to use a general way to handle any bit enable operation required without special cases.
Virtual LDN's can be used in Coreboot to uniquely map the enable bit position in register 0x30 of an LDN, this allows to use a general way to handle any bit enable operation required without special cases.

Revision as of 23:26, 2 March 2016