Angel Pons has uploaded this change for review.

View Change

nb/intel/haswell/northbridge.c: Correct DPR handling

DPR size is in MiB, but the range boundaries are expressed in KiB. In
addition, DPR and TSEG use the same attributes, so unify both regions.
Also improve a comment about DPR, since `is special` is uninformative.

Change-Id: I4479483e17890b5a4c39165138fa1c5f8215bc84
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
---
M src/northbridge/intel/haswell/northbridge.c
1 file changed, 11 insertions(+), 14 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/87/46987/1

diff --git a/src/northbridge/intel/haswell/northbridge.c b/src/northbridge/intel/haswell/northbridge.c
index 64a274d..e31337b 100644
--- a/src/northbridge/intel/haswell/northbridge.c
+++ b/src/northbridge/intel/haswell/northbridge.c
@@ -289,7 +289,12 @@
 	mc_read_map_entries(dev, &mc_values[0]);
 	mc_report_map_entries(dev, &mc_values[0]);
 
-	/* The DPR register is special */
+	/*
+	 * DMA Protected Range can be reserved below TSEG for PCODE patch
+	 * or TXT/BootGuard related data.  Rather than report a base address,
+	 * the DPR register reports the TOP of the region, which is the same
+	 * as TSEG base. The region size is reported in MiB in bits 11:4.
+	 */
 	const union dpr_register dpr = {
 		.raw = pci_read_config32(dev, DPR),
 	};
@@ -328,23 +333,15 @@
 	size_k = (0xa0000 >> 10) - base_k;
 	ram_resource(dev, index++, base_k, size_k);
 
-	/* 0xc0000 -> DPR base */
+	/* 0xc0000 -> TSEG - DPR */
 	base_k = 0xc0000 >> 10;
-	size_k = (unsigned long)(mc_values[TSEG_REG] >> 10) - (base_k + dpr.size);
+	size_k = (unsigned long)(mc_values[TSEG_REG] >> 10) - base_k;
+	size_k -= dpr.size >> 10;
 	ram_resource(dev, index++, base_k, size_k);
 
-	/* DPR base -> TSEG */
-	if (dpr.size) {
-		resource = new_resource(dev, index++);
-		resource->base = (dpr.top - dpr.size) * MiB;
-		resource->size = dpr.size * MiB;
-		resource->flags = IORESOURCE_MEM | IORESOURCE_STORED | IORESOURCE_CACHEABLE |
-				  IORESOURCE_RESERVE | IORESOURCE_ASSIGNED | IORESOURCE_FIXED;
-	}
-
-	/* TSEG -> BGSM */
+	/* TSEG - DPR -> BGSM */
 	resource = new_resource(dev, index++);
-	resource->base = mc_values[TSEG_REG];
+	resource->base = mc_values[TSEG_REG] - dpr.size;
 	resource->size = mc_values[BGSM_REG] - resource->base;
 	resource->flags = IORESOURCE_MEM | IORESOURCE_FIXED | IORESOURCE_STORED |
 			  IORESOURCE_RESERVE | IORESOURCE_ASSIGNED | IORESOURCE_CACHEABLE;

To view, visit change 46987. To unsubscribe, or for help writing mail filters, visit settings.