On 10/20/25 12:48 PM, Joel Fernandes wrote: > > >> On Oct 20, 2025, at 3:36 PM, John Hubbard <[email protected]> wrote: >> >> On 10/20/25 11:55 AM, Joel Fernandes wrote: >> ...> +Logically, the PRAMIN aperture mechanism is implemented by the GPU's >> PBUS (PCIe Bus Controller Unit) >>> +and provides a CPU-accessible window into VRAM through the PCIe interface:: >>> + >>> + +-----------------+ PCIe +------------------------------+ >>> + | CPU |<----------->| GPU | >>> + +-----------------+ | | >>> + | +----------------------+ | >>> + | | PBUS | | >>> + | | (Bus Controller) | | >>> + | | | | >>> + | | +--------------.<------------ >>> (window always starts at >>> + | | | PRAMIN | | | >>> BAR0 + 0x700000) >> >> Quick question: does "window always starts at" actually mean "windows >> is always initialized to" ? Or something else? > > It means start of the 1MB window (offset 0) is accessed from the BAR at that > location. > OK, yes. May I suggest this slightly tweaked wording:
(window into VRAM starts at BAR0 + 0x700000) ? This avoids "always" (because HW may change someday), and also gives a subtly stronger hint about how this is laid out. thanks, -- John Hubbard
