On Thu, Jun 11, 2020 at 04:17 PM, Ard Biesheuvel wrote:<br />
<blockquote>On 6/11/20 4:07 PM, greg@unrelenting.technology wrote:<br />
<blockquote>June 11, 2020 4:19 PM, "Ard Biesheuvel" &lt;ard.biesheuvel@arm.com&gt; wrote:<br /><br />
<blockquote>On 6/5/20 5:19 PM, Marcin Wojtas via groups.io wrote:<br /><br />
<blockquote>Hi,<br />I'd like to ask for comments before I develop the actual code - &gt; currently we have 2 workarounds<br />done specifically for Linux:<br />a. ECAM shift in PCIE<br />b. SPCR address space definition</blockquote>
What does this mean?</blockquote>
The SPCR in upstream edk2 is set up to work around some Linux weirdness (?) and I have to do this:<br /><br /><a href="https://github.com/myfreeweb/edk2-platforms/commit/74ec98a6498e78d2ae6c861db88487bf75f2e1a1" target="_blank" rel="noopener">https://github.com/myfreeweb/edk2-platforms/commit/74ec98a6498e78d2ae6c861db88487bf75f2e1a1</a><br /><br />to make it work on FreeBSD.</blockquote>
Surely, they can't both be correct. Marcin?<br /><br /></blockquote>
Assuming the serial port on Armada/Cn911x is the same as on Armada8k, the following DT properties would be applicable:<br /><br />reg-shift = &lt;2&gt;;<br />reg-io-width = &lt;1&gt;<br /><br />which means the registers are spaced 32-bits apart but have to be accessed using 8-bit load/store instructions.&nbsp; I'd say that<br />means that the ACPI Generic Address Space should have RegisterBitWidth set to 32 and AccessSize set to BYTE.<br />In other words, I think that the current:<br /><br />
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<div>#define MV_UART_AS32(Address) { EFI_ACPI_5_0_SYSTEM_MEMORY, 32, 0, EFI_ACPI_5_0_BYTE, Address }<br /><br />is correct.&nbsp; That certainly is what works for OpenBSD.</div>
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