4 files changed, 16 insertions, 10 deletions
diff --git a/src/northbridge/intel/gm45/raminit.c b/src/northbridge/intel/gm45/raminit.c
index 03f617c6a3..d067dc2ff9 100644
--- a/src/northbridge/intel/gm45/raminit.c
+++ b/src/northbridge/intel/gm45/raminit.c
@@ -1242,12 +1242,13 @@ static void program_memory_map(const dimminfo_t *const dimms, const channel_mode
 
 			uma_sizem = (gms_sizek + gsm_sizek) >> 10;
 		}
-		/* TSEG 8M */
+		/* TSEG 2M, This amount can easily be covered by SMRR MTRR's,
+		   which requires to have TSEG_BASE aligned to TSEG_SIZE. */
 		u8 reg8 = pci_read_config8(PCI_DEV(0, 0, 0), D0F0_ESMRAMC);
 		reg8 &= ~0x7;
-		reg8 |= (2 << 1) | (1 << 0); /* 8M and TSEG_Enable */
+		reg8 |= (1 << 1) | (1 << 0); /* 2M and TSEG_Enable */
 		pci_write_config8(PCI_DEV(0, 0, 0), D0F0_ESMRAMC, reg8);
-		uma_sizem += 8;
+		uma_sizem += 2;
 	}
 
 	const unsigned int mmio_size = get_mmio_size();
diff --git a/src/northbridge/intel/i945/early_init.c b/src/northbridge/intel/i945/early_init.c
index a38874a563..d516db76b9 100644
--- a/src/northbridge/intel/i945/early_init.c
+++ b/src/northbridge/intel/i945/early_init.c
@@ -191,10 +191,11 @@ static void i945_setup_bars(void)
 	if (gfxsize > 6)
 		gfxsize = 2;
 	pci_write_config16(PCI_DEV(0, 0x00, 0), GGC, ((gfxsize + 1) << 4));
-
+	/* TSEG 2M, This amount can easily be covered by SMRR MTRR's,
+	   which requires to have TSEG_BASE aligned to TSEG_SIZE. */
 	reg8 = pci_read_config8(PCI_DEV(0, 0, 0), ESMRAMC);
 	reg8 &= ~0x7;
-	reg8 |= (2 << 1) | (1 << 0); /* 8M and TSEG_Enable */
+	reg8 |= (1 << 1) | (1 << 0); /* 2M and TSEG_Enable */
 	pci_write_config8(PCI_DEV(0, 0, 0), ESMRAMC, reg8);
 
 	/* Set C0000-FFFFF to access RAM on both reads and writes */
diff --git a/src/northbridge/intel/pineview/raminit.c b/src/northbridge/intel/pineview/raminit.c
index 778b2f7f52..f199d9beed 100644
--- a/src/northbridge/intel/pineview/raminit.c
+++ b/src/northbridge/intel/pineview/raminit.c
@@ -2034,7 +2034,9 @@ static void sdram_mmap_regs(struct sysinfo *s)
 	gttsize = ggc_to_gtt[(ggc & 0x300) >> 8];
 	tom = s->channel_capacity[0];
 
-	tsegsize = 0x8; // 8MB
+	/* TSEG 2M, This amount can easily be covered by SMRR MTRR's,
+	   which requires to have TSEG_BASE aligned to TSEG_SIZE. */
+	tsegsize = 0x2;
 	mmiosize = 0x400; // 1GB
 
 	reclaim = false;
@@ -2071,7 +2073,7 @@ static void sdram_mmap_regs(struct sysinfo *s)
 
 	u8 reg8 = pci_read_config8(PCI_DEV(0, 0, 0), ESMRAMC);
 	reg8 &= ~0x7;
-	reg8 |= (2 << 1) | (1 << 0); /* 8M and TSEG_Enable */
+	reg8 |= (1 << 1) | (1 << 0); /* 2M and TSEG_Enable */
 	pci_write_config8(PCI_DEV(0, 0, 0), ESMRAMC, reg8);
 
 	printk(BIOS_DEBUG, "GBSM (igd) = verified %08x (written %08x)\n",
diff --git a/src/northbridge/intel/x4x/raminit_ddr23.c b/src/northbridge/intel/x4x/raminit_ddr23.c
index c445cad12e..a94e9ca31c 100644
--- a/src/northbridge/intel/x4x/raminit_ddr23.c
+++ b/src/northbridge/intel/x4x/raminit_ddr23.c
@@ -1722,7 +1722,9 @@ static void configure_mmap(struct sysinfo *s)
 	ggc = pci_read_config16(PCI_DEV(0, 0, 0), 0x52);
 	gfxsize = ggc2uma[(ggc & 0xf0) >> 4];
 	gttsize = ggc2gtt[(ggc & 0xf00) >> 8];
-	tsegsize = 8; // 8MB TSEG
+	/* TSEG 2M, This amount can easily be covered by SMRR MTRR's,
+	   which requires to have TSEG_BASE aligned to TSEG_SIZE. */
+	tsegsize = 2;
 	mmiosize = 0x800; // 2GB MMIO
 	umasizem = gfxsize + gttsize + tsegsize;
 	mmiostart = 0x1000 - mmiosize + umasizem;
@@ -1759,10 +1761,10 @@ static void configure_mmap(struct sysinfo *s)
 	pci_write_config16(PCI_DEV(0, 0, 0), 0xa2, touud);
 	pci_write_config32(PCI_DEV(0, 0, 0), 0xa4, gfxbase << 20);
 	pci_write_config32(PCI_DEV(0, 0, 0), 0xa8, gttbase << 20);
-	/* Enable and set tseg size to 8M */
+	/* Enable and set tseg size to 2M */
 	reg8 = pci_read_config8(PCI_DEV(0, 0, 0), D0F0_ESMRAMC);
 	reg8 &= ~0x7;
-	reg8 |= (2 << 1) | (1 << 0); /* 8M and TSEG_Enable */
+	reg8 |= (1 << 1) | (1 << 0); /* 2M and TSEG_Enable */
 	pci_write_config8(PCI_DEV(0, 0, 0), D0F0_ESMRAMC, reg8);
 	pci_write_config32(PCI_DEV(0, 0, 0), 0xac, tsegbase << 20);
 }