Filip Navara wrote:
Hartmut Birr wrote:
Filip Navara wrote:
- At first, the UseMapRegisters variable you added to
MAP_REGISTER_ENTRY structure isn't needed. IoFlushAdapterBuffers can determine the information itself and the case was clearly marked as UNIMPLEMENTED and FIXME.
This case isn't marked as UNIMPLEMENTED and FIXME. The using of hardware scatter/gather is marked as UNIMPLEMENTED and FIXME. I've modified the cache manager a little bit. The cache segments for the floppy driver allocated from below the 16MB limit. I get no data from a floppy.
The UNIMPLEMENTED case is entered for any adapter that claims that it can support hardware scatter/gather regardless of it being used or not. A quick untested patch is attached (I'm not sure it will work, since it looks like I forgot to initialize MapRegisterBase->Counter...). I'm planning to look at it.
- The byte offset is added for a reason. I know the stuff that it is
supposed to solve is broken atm, but the rationale is that there can be more IoMapTransfer calls and together with MAP_REGISTER_ENTRY->Counter you can setup more transfers... It's explained in http://download.microsoft.com/download/e/b/a/eba1050f-a31d-436b-9281-92cdfea...
It makes no sense to call IoMapTransfer more than ones without a call to IoFlushAdapterBuffers for the pc dma controllers. For the pc dma controllers, a transfer has to be finished, before the next can be started.
It applies to non-system-DMA... Quoting NT4 DDK documentation: "The driver of a busmaster device with scatter/gather support can use the returned logical address and updated Length value to build a scatter/gather list, calling IoMapTransfer repeatedly until it has used all available map registers for the transfer operation."
It is always possible to call IoFlushAdapterBuffers after each transfer and before the next is started. The reference doesn't explain something about to setup more transfers.
See above.
I'll try to write more tomorrow, but my mind is getting foggy now...
Oh, this time with the right patch...
- Filip