On 04.09.24 12:16, Siddharth Vadapalli wrote:

On Wed, Sep 04, 2024 at 12:00:11PM +0200, Jan Kiszka wrote:

quoted

From: Jan Kiszka <jan.kiszka@siemens.com>

The PVU on the AM65 SoC is capable of restricting DMA from PCIe devices
to specific regions of host memory. Add the optional property
"memory-regions" to point to such regions of memory when PVU is used.

Since the PVU deals with system physical addresses, utilizing the PVU
with PCIe devices also requires setting up the VMAP registers to map the
Requester ID of the PCIe device to the CBA Virtual ID, which in turn is
mapped to the system physical address. Hence, describe the VMAP
registers which are optionally unless the PVU shall used for PCIe.

The last line above seems to be accidentally modified when compared to
the one at:
https://lore.kernel.org/r/ada462d5-157a-4e11-ba25-d412a2bb678f@ti.com/ (local)
"Hence, describe the VMAP registers which are optionally
configured whenever PVU is used for PCIe."

If you intended to modify it, then the sentence appears distorted.

Yeah, I wanted to make the original sentence clearer but failed:
"...which are optional unless the PVU shall be used for PCIe."

Jan

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