intel_chipset: Replace lookup of GT size with computation

Instead of a large if-chain for matching devid to GT, we can just
compute it directly from the encoded devid.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

1 files changed, 23 insertions, 0 deletions

diff --git a/lib/intel_device_info.c b/lib/intel_device_info.c
index 9e194945..12bce7ea 100644
--- a/lib/intel_device_info.c
+++ b/lib/intel_device_info.c
@@ -286,3 +286,26 @@ unsigned intel_gen(uint16_t devid)
 {
 	return ffs(intel_device_info(devid)->gen);
 }
+
+/**
+ * intel_gt:
+ * @devid: pci device id
+ *
+ * Computes the Intel GFX GT size for the given device id.
+ *
+ * Returns:
+ * The GT size.
+ */
+unsigned intel_gt(uint16_t devid)
+{
+	unsigned mask = intel_gen(devid);
+
+	if (mask >= 8)
+		mask = 0xf;
+	else if (mask >= 6)
+		mask = 0x3;
+	else
+		mask = 0;
+
+	return (devid >> 4) & mask;
+}