On 7/12/25 1:42 AM, Krishna Chaitanya Chundru wrote:
> The ELBI registers falls after the DBI space, PARF_SLV_DBI_ELBI register
> gives us the offset from which ELBI starts. So override ELBI with the
> offset from PARF_SLV_DBI_ELBI and cfg win to map these regions.
>
> On root bus, we have only the root port. Any access other than that
> should not go out of the link and should return all F's. Since the iATU
> is configured for the buses which starts after root bus, block the
> transactions starting from function 1 of the root bus to the end of
> the root bus (i.e from dbi_base + 4kb to dbi_base + 1MB) from going
> outside the link through ECAM blocker through PARF registers.
>
> Signed-off-by: Krishna Chaitanya Chundru <krishna.chundru@xxxxxxxxxxxxxxxx>
> ---
[...]
> + if (pp->ecam_mode) {
> + /*
> + * Override ELBI in ecam mode, as in ecam mode
> + * ELBI moves along with the dbi config space.
> + */
> + offset = readl(pcie->parf + PARF_SLV_DBI_ELBI);
I see that the offset is supposed to take up 12 lower bits with the
remaining ones being reserved. Out of abundance of caution, please
add a #define SLV_DBI_ELBI_ADDR_BASE GENMASK(11, 0) and FIELD_GET it
no concerns apart from that, I think
Konrad
