Revision as of 23:25, 13 March 2011

This is a proposal for PC System Flash emulation for on QEMU/KVM.

Flash Hardware

Leverage the pre-existing CFI flash support in qemu/hw/pflash_cfi01.c (or perhaps qemu/hw/pflash_cfi02.c).

Command line interface

Today the (currently existing) -pflash parameter has no use with an x86 or x86-64 system. To enable PC system flash, this parameter would now be used on x86 & x86-64 systems. The -bios parameter would take priority over -pflash, but one or both could be used with qemu/kvm as follows:

-bios used	-pflash used	Result
No	No	(no change) 'bios.bin' will be loaded as rom image.
Yes	No	(no change) -bios parameter will be loaded as rom image.
No	Yes	(changing) -pflash parameter will be loaded as flash image just below 4GB. 'bios.bin' will be ignored.
Yes	Yes	(changing) -bios parameter will be loaded as rom image just below 4GB. -pflash parameter will be loaded as flash image just below the bios rom image.

@@ Line 14: / Line 14: @@
 ! -bios used !! -pflash used !! Result
 |-
-| <Center>N</Center> || <Center>N</Center> || (no change) 'bios.bin' will be loaded as rom image.
+| <Center>No</Center> || <Center>No</Center> || (no change) 'bios.bin' will be loaded as rom image.
 |-
-| <Center>Y</Center> || <Center>N</Center> || (no change) -bios parameter will be loaded as rom image.
+| <Center>Yes</Center> || <Center>No</Center> || (no change) -bios parameter will be loaded as rom image.
 |-
-| <Center>N</Center> || <Center>Y</Center>
+| <Center>No</Center> || <Center>Yes</Center>
 | ('''changing''') -pflash parameter will be loaded as flash image just below 4GB.
 'bios.bin' will be ''ignored''.
 |-
-| <Center>Y</Center> || <Center>Y</Center>
+| <Center>Yes</Center> || <Center>Yes</Center>
 | ('''changing''') -bios parameter will be loaded as rom image just below 4GB.
 -pflash parameter will be loaded as flash image just below the bios rom image.
 |}