PSP VSH Mode?

Dariusc123456 · Post by **Dariusc123456** » Tue Jun 30, 2009 8:26 pm

Hey,
I have a question about the vsh mode - 0x0800 thats use for the psp to access VSH mode. What functions are then allow when you are in VSH mode? I know what User and Kernel Function are, but vsh?

I have never use 0x800, and I ask because I took a look at 3.40 OE source code and found that in there.

m0skit0 · Post by **m0skit0** » Tue Jun 30, 2009 11:45 pm

VSH mode corresponds to supervisor mode in MIPS modes. It's a mode between user and kernel. More access than user, less access than kernel :)

Dariusc123456 · Post by **Dariusc123456** » Wed Jul 01, 2009 2:40 pm

So VSH mode is just a mid-mode to access user (more) and kernel (less)?

ne0h · Post by **ne0h** » Thu Jul 02, 2009 4:01 am

m0skit0 wrote:VSH mode corresponds to supervisor mode in MIPS modes. It's a mode between user and kernel. More access than user, less access than kernel :)

Just read?

coolkehon · Post by **coolkehon** » Thu Jul 02, 2009 4:18 am

so what exactly can this do extra besides user and how do i get my app to start in this

m0skit0 · Post by **m0skit0** » Thu Jul 02, 2009 9:10 am

As far as MIPS concerns, supervisor mode has access to 0xc0000000 to 0xdfffffff besides access to user mode memory (below 0x80000000). But how this translates to the actual PSP architecture, I don't know...

Dariusc123456 · Post by **Dariusc123456** » Thu Jul 02, 2009 12:07 pm

I wonder if there's an extra memory that has a higher user and kernel. I am not talking about service mode (if there is one), but there's has to be something Sony use to access the extra memory that we cant get into. If we can access this memory, maybe we can dump the pre-IPL without service mode.

Torch · Post by **Torch** » Thu Jul 02, 2009 2:39 pm

Some of the firmware functions have different privileges in VSH mode. In some cases even more than kernel mode. E.g. You can directly reassign flash0: for write access in VSH mode using the usual sce* functions, but you cannot do this even in kernel mode without some extra work like manually setting user level etc.