[PATCH 2/3] fwts_firmware: Rework Devicetree firmware detection

[Rob Herring]

Currently, ACPI is assumed for UEFI based systems, but Arm based UEFI
systems may use ACPI or DT for hardware description. It's also possible
to have DT without UEFI or OPAL such as non-UEFI u-boot.

Rework the feature detection to ignore the firmware type and just check
sysfs. As Arm systems always have a DT for boot parameters even with
ACPI, check for ACPI firmware first.

Signed-off-by: Rob Herring <robh at kernel.org>
---
 src/lib/src/fwts_firmware.c | 21 +++++++--------------
 1 file changed, 7 insertions(+), 14 deletions(-)

diff --git a/src/lib/src/fwts_firmware.c b/src/lib/src/fwts_firmware.c
index ba0b939c09ba..b249f00a9917 100644
--- a/src/lib/src/fwts_firmware.c
+++ b/src/lib/src/fwts_firmware.c
@@ -54,22 +54,15 @@ fwts_firmware_type fwts_firmware_detect(void)
 int fwts_firmware_features(void)
 {
 	int features = 0;
-	struct stat ipmi_statbuf;
-
-	switch (fwts_firmware_detect()) {
-	case FWTS_FIRMWARE_BIOS:
-	case FWTS_FIRMWARE_UEFI:
-		features = FWTS_FW_FEATURE_ACPI;
-		break;
-	case FWTS_FIRMWARE_OPAL:
-		features = FWTS_FW_FEATURE_DEVICETREE;
-		break;
-	default:
-		break;
-	}
+	struct stat statbuf;
+
+	if (!stat("/sys/firmware/acpi", &statbuf))
+		features |= FWTS_FW_FEATURE_ACPI;
+	else if (!stat("/sys/firmware/devicetree/base", &statbuf))
+		features |= FWTS_FW_FEATURE_DEVICETREE;
 
 	/* just check for IPMI device presence */
-	if (!stat("/dev/ipmi0", &ipmi_statbuf))
+	if (!stat("/dev/ipmi0", &statbuf))
 		features |= FWTS_FW_FEATURE_IPMI;
 
 	return features;
-- 
2.30.2