soc/intel/skylake: Factor out unnecessary if-else-block

Move InternalGfx config option out of the if-else-block and replace the
left over config option IgdDvmt50PreAlloc by a ternary expression. Also,
adjust related code comments to fit the new logic of this code.

This changes the logic of the code, since InternalGfx is configured
first and IgdDvmt50PreAlloc depends on its value. The negation in the
ternary expression is removed to improve the readability.

Change-Id: I89ff17f4574a7ade228c1791f17ea072fb731775
Signed-off-by: Felix Singer <felixsinger@posteo.net>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/44369
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Michael Niewöhner

1 files changed, 14 insertions, 19 deletions

diff --git a/src/soc/intel/skylake/romstage/romstage.c b/src/soc/intel/skylake/romstage/romstage.c
index 7410925a1f..9add1e688f 100644
--- a/src/soc/intel/skylake/romstage/romstage.c
+++ b/src/soc/intel/skylake/romstage/romstage.c
@@ -247,25 +247,20 @@ static void soc_primary_gfx_config_params(FSP_M_CONFIG *m_cfg,
 	const struct device *dev;
 
 	dev = pcidev_path_on_root(SA_DEVFN_IGD);
-	if (!dev || !dev->enabled) {
-		/*
-		 * If iGPU is disabled or not defined in the devicetree.cb,
-		 * the FSP does not initialize this device
-		 */
-		m_cfg->InternalGfx = 0;
-		m_cfg->IgdDvmt50PreAlloc = 0;
-	} else {
-		m_cfg->InternalGfx = 1;
-		/*
-		 * Set IGD stolen size to 64MB.  The FBC hardware for skylake
-		 * does not have access to the bios_reserved range so it always
-		 * assumes 8MB is used and so the kernel will avoid the last
-		 * 8MB of the stolen window. With the default stolen size of
-		 * 32MB(-8MB) there is not enough space for FBC to work with
-		 * a high resolution panel
-		 */
-		m_cfg->IgdDvmt50PreAlloc = 2;
-	}
+	m_cfg->InternalGfx = dev && dev->enabled;
+
+	/*
+	 * If iGPU is enabled, set IGD stolen size to 64MB. The FBC
+	 * hardware for skylake does not have access to the bios
+	 * reserved range so it always assumes 8MB is used and so the
+	 * kernel will avoid the last 8MB of the stolen window. With
+	 * the default stolen size of 32MB(-8MB) there is not enough
+	 * space for FBC to work with a high resolution panel.
+	 *
+	 * If disabled, don't reserve memory for it.
+	 */
+	m_cfg->IgdDvmt50PreAlloc = m_cfg->InternalGfx ? 2 : 0;
+
 	m_cfg->PrimaryDisplay = config->PrimaryDisplay;
 }