Question about rsdp test?

[Al Stone]

On 07/18/2016 06:06 AM, Dong, Eric wrote:
> When I do the Fwts test, I got below error for the rsdp test.
> 
> rsdp           ;HED rsdp: RSDP Root System Description Pointer test.
> 
> rsdp           ;SEP ------------------------------------------------------------
> 
> rsdp           ;INF Test 1 of 1: RSDP Root System Description Pointer test.
> 
> rsdp           ;PAS PASSED: Test 1, RSDP first checksum is correct
> 
> rsdp           ;PAS PASSED: Test 1, RSDP: oem_id contains only printable
> 
> rsdp           ;PAS characters.
> 
> rsdp           ;PAS PASSED: Test 1, RSDP: revision is 2.
> 
> rsdp           ;PAS PASSED: Test 1, RSDP: at least one of RsdtAddress or
> 
> rsdp           ;PAS XsdtAddress is non-zero.
> 
> rsdp           ;FAL FAILED [MEDIUM] RSDPBothAddressesFound: Test 1, RSDP: only
> 
> rsdp           ;FAL one of RsdtAddress or XsdtAddress should be non-zero. Both
> 
> rsdp           ;FAL fields are non-zero.
> 
> rsdp           ;PAS PASSED: Test 1, RSDP: the correct RSDT/XSDT address is being
> 
> rsdp           ;PAS used.
> 
> rsdp           ;PAS PASSED: Test 1, RSDP: the table is the correct length.
> 
> rsdp           ;PAS PASSED: Test 1, RSDP second checksum is correct
> 
> rsdp           ;PAS PASSED: Test 1, RSDP: the reserved field is zero.
> 
> rsdp           ;NLN
> 
> rsdp           ;SEP ============================================================
> 
> rsdp           ;SUM 8 passed, 1 failed, 0 warning, 0 aborted, 0 skipped, 0 info
> 
> rsdp           ;SUM only.
> 
> rsdp           ;SEP ============================================================
> 
>  
> 
> I think it caused by both Rsdt and Xsdt address are not zero. But From ACPI 6.0
> spec: (page 115)
> 
> Notice that both the XSDT and the RSDT can be pointed to by the RSDP structure.
> An ACPI-compatible OS must use the XSDT if present.
> 
>  
> 
> From the above description, I think the spec allowed the case of both Xsdt and
> Rsdt are not zero.  So I think Fwts tool should not report error for this case,
> am I correct?
> 
>  
> 
> Thanks,
> 
> Eric

On what architecture?  If this is on ARMv8, we should not be using an RSDT,
according to SBSA/SBBR specifications.  If this is on x86, or perhaps ia64,
then the test probably needs to allow for that, if it doesn't already.

Personally, I'd really like to discourage new systems from using the 32-bit
tables.

-- 
ciao,
al
-----------------------------------
Al Stone
Software Engineer
Linaro Enterprise Group
al.stone at linaro.org
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