ACK: [PATCH v2 3/3] ACPI: a missing FACS table can be ignored under some circumstances

[Alex Hung]

On 12/03/2014 01:35 AM, Fu Wei wrote:
> (1)Both of the FADT fields FIRMWARE_CTRL and X_FIRMWARE_CTRL
>  are allowed to be null, if and only if ACPI is operating in hardware- reduced
>  mode.
> (2)If the ACPI tables are from before ACPI 5.0, or if ACPI is not
>  operating in hardware-reduced mode, at least one of the FIRMWARE_CTRL or
>  X_FIRMWARE_CTRL fields _must_ be non-null.
> 
> This patch corrects the logic to ensure that a missing FACS is only
> allowed under the proper circumstances.
> 
> Signed-off-by: Fu Wei <fu.wei at linaro.org>
> Acked-by: Hanjun Guo <hanjun.guo at linaro.org>
> Reviewed-by: Al Stone <al.stone at linaro.org>
> ---
>  src/acpi/acpitables/acpitables.c |  5 +++--
>  src/lib/src/fwts_acpi_tables.c   | 24 +++++++++++++++++-------
>  2 files changed, 20 insertions(+), 9 deletions(-)
> 
> diff --git a/src/acpi/acpitables/acpitables.c b/src/acpi/acpitables/acpitables.c
> index 255261c..3d261cb 100644
> --- a/src/acpi/acpitables/acpitables.c
> +++ b/src/acpi/acpitables/acpitables.c
> @@ -75,10 +75,11 @@ static void acpi_table_check_fadt(fwts_framework *fw, fwts_acpi_table_info *tabl
>  
>  	if (fadt->firmware_control == 0) {
>  		if (table->length >= 140) {
> -			if (fadt->x_firmware_ctrl == 0) {
> +			if ((fadt->x_firmware_ctrl == 0) && !(fwts_acpi_is_reduced_hardware(fadt))) {
>  				fwts_failed(fw, LOG_LEVEL_CRITICAL, "FADTFACSZero", "FADT 32 bit FIRMWARE_CONTROL and 64 bit X_FIRMWARE_CONTROL (FACS address) are null.");
>  				fwts_advice(fw, "The 32 bit FIRMWARE_CTRL or 64 bit X_FIRMWARE_CTRL should point to a valid "
> -						"Firmware ACPI Control Structure (FACS). This is a firmware bug and needs to be fixed.");
> +						"Firmware ACPI Control Structure (FACS) when ACPI hardware reduced mode is not set. "
> +						"This is a firmware bug and needs to be fixed.");
>  			}
>  		} else {
>  			fwts_failed(fw, LOG_LEVEL_MEDIUM, "FADT32BitFACSNull", "FADT 32 bit FIRMWARE_CONTROL is null.");
> diff --git a/src/lib/src/fwts_acpi_tables.c b/src/lib/src/fwts_acpi_tables.c
> index ee592d6..68211e5 100644
> --- a/src/lib/src/fwts_acpi_tables.c
> +++ b/src/lib/src/fwts_acpi_tables.c
> @@ -373,6 +373,7 @@ static int fwts_acpi_handle_fadt(
>  	const fwts_acpi_table_provenance provenance)
>  {
>  	static uint64_t	facs_last_phys_addr;	/* default to zero */
> +	int result = FWTS_ERROR;
>  
>  	/*
>  	 *  The FADT handling may occur twice if it appears
> @@ -384,13 +385,22 @@ static int fwts_acpi_handle_fadt(
>  
>  	facs_last_phys_addr = phys_addr;
>  
> -	/* Determine FACS addr and load it */
> -	if (fwts_acpi_handle_fadt_tables(fw, fadt,
> -	    "FACS", "FIRMWARE_CTRL", "X_FIRMWARE_CTRL",
> -	     &fadt->firmware_control, &fadt->x_firmware_ctrl,
> -	     provenance) != FWTS_OK) {
> -		fwts_log_error(fw, "Failed to load FACS.");
> -		return FWTS_ERROR;
> +	/* Determine FACS addr and load it.
> +	 * Will ignore the missing FACS in the hardware-reduced mode.
> +	 */
> +	result = fwts_acpi_handle_fadt_tables(fw, fadt,
> +			"FACS", "FIRMWARE_CTRL", "X_FIRMWARE_CTRL",
> +			&fadt->firmware_control, &fadt->x_firmware_ctrl,
> +			provenance);
> +	if (result != FWTS_OK) {
> +		if ((result == FWTS_NULL_POINTER) &&
> +				fwts_acpi_is_reduced_hardware(fadt)) {
> +			fwts_log_info(fw, "Ignore the missing FACS. "
> +					"It is optional in hardware-reduced mode");
> +		} else {
> +			fwts_log_error(fw, "Failed to load FACS.");
> +			return FWTS_ERROR;
> +		}
>  	}
>  	/* Determine DSDT addr and load it */
>  	if (fwts_acpi_handle_fadt_tables(fw, fadt,
> 

Acked-by: Alex Hung <alex.hung at canonical.com>

-- 
Cheers,
Alex Hung