arch/powerpc/pci_iov_resource_on_powernv.rst

59       Each window can be configured to be remapped via a "TCE table" (IOMMU
76     window and sixteen M64 windows.  They have different characteristics.
81     - The M32 window:
87 	32-bit PCIe accesses.  We configure that window at boot from FW and
97 	to be assigned to PEs on a segment granularity.  For a 2GB window,
100     Now, this is the "main" window we use in Linux today (excluding
119 	specify the PE# for the entire window.  When segmented, a window
124 	there's a defined ordering for which window applies.
129     We configure an M64 window to cover the entire region of address space
188   - M32 window: There's one M32 window, and it is split into 256
190     window with 1MB segments.  VF BARs that are 1MB or larger could be
191     mapped to separate PEs in this window.  Each segment can be
194     they are different sizes, the entire window has to be small enough that
198   - Non-segmented M64 window: A non-segmented M64 window is mapped entirely
201   - Single segmented M64 windows: A segmented M64 window could be used just
202     like the M32 window, but the segments can't be individually mapped to
207   - Multiple segmented M64 windows: As usual, each window is split into 256
211     and a 32MB BAR, we could use one M64 window to assign 1MB segments and
212     another M64 window to assign 32MB segments.
218   segments/PEs inside that M64 window.
223   range to PE#.  Each M64 window defines one MMIO range and this range is
226   We decide to leverage this M64 window to map VFs to individual PEs, since
230   than the number of M64 window segments, so if we map one VF BAR directly
231   to one M64 window, some part of the M64 window will map to another
236   segments [total_VFs, 255] of the M64 window may map to some MMIO range on
251                            M64 window
270 			   M64 window
274   Allocating the extra space ensures that the entire M64 window will be
288 window, we can set the PE# by updating the table that translates segments
289 to PE#s.  Similarly, if the address is in an unsegmented M64 window, we can
290 set the PE# for the window.  But if it's in a segmented M64 window, the