[PATCH] mtrr: add tests for enable bits in MTRR_DEF_TYPE MSR

[Colin Ian King]

On 17/11/2020 06:50, Alex Hung wrote:
> Signed-off-by: Alex Hung <alex.hung at canonical.com>
> ---
>  src/bios/mtrr/mtrr.c | 30 ++++++++++++++++++++++++++++++
>  1 file changed, 30 insertions(+)
> 
> diff --git a/src/bios/mtrr/mtrr.c b/src/bios/mtrr/mtrr.c
> index c9b77941..ca1dbc2c 100644
> --- a/src/bios/mtrr/mtrr.c
> +++ b/src/bios/mtrr/mtrr.c
> @@ -594,6 +594,35 @@ static int mtrr_deinit(fwts_framework *fw)
>  	return FWTS_OK;
>  }
>  
> +static int mtrr_test0(fwts_framework *fw)
> +{
> +	uint64_t mtrr_def_msr;

Can you add an empty line here before the if statement

> +	if (fwts_cpu_readmsr(fw, 0, MTRR_DEF_TYPE_MSR, &mtrr_def_msr) != FWTS_OK) {
> +		fwts_failed(fw, LOG_LEVEL_CRITICAL,
> +			"MTRRMSRDefaultNotAvailable",
> +			"MTRR_DEF_TYPE_MSR cannot be read from CPU.");
> +		return FWTS_OK;

is FWTS_OK correct to return when the msr read failed?

> +	}
> +
> +	if (mtrr_def_msr & 0x800)

Can you #define the 0x800 magic value to add more context to what that
value is?

> +		fwts_passed(fw, "MTRRs enabled flag is set in MTRR_DEF_TYPE MSR correctly.");
> +	else
> +		fwts_failed(fw, LOG_LEVEL_CRITICAL,
> +			"MTRRDisabled",
> +			"MTRRs enabled flag is clear in MTRR_DEF_TYPE MSR and "
> +			"all MTRRs are disabled ");
> +
> +	if (mtrr_def_msr & 0x400)

Same here with the 0x400 value

> +		fwts_passed(fw, "fixed MTRRs enabled flag is set in MTRR_DEF_TYPE MSR correctly.");
> +	else
> +		fwts_failed(fw, LOG_LEVEL_CRITICAL,
> +			"MTRRFixedRangeDisabled",
> +			"Fixed MTRRs enabled flag is clear in MTRR_DEF_TYPE MSR and "
> +			"all Fixed-range MTRRs are disabled ");
> +
> +	return FWTS_OK;
> +}
> +
>  static int mtrr_test1(fwts_framework *fw)
>  {
>  	return validate_iomem(fw);
> @@ -658,6 +687,7 @@ static int mtrr_test3(fwts_framework *fw)
>  }
>  
>  static fwts_framework_minor_test mtrr_tests[] = {
> +	{ mtrr_test0, "Validate MTRR default enabled." },
>  	{ mtrr_test1, "Validate the kernel MTRR IOMEM setup." },
>  	{ mtrr_test2, "Validate the MTRR setup across all processors." },
>  	{ mtrr_test3, "Test for AMD MtrrFixDramModEn being cleared by the BIOS." },
>