diff --git a/chipset_enable.c b/chipset_enable.c
index 76893a1..04b1a1c 100644
--- a/chipset_enable.c
+++ b/chipset_enable.c
@@ -36,8 +36,6 @@
 
 #if defined(__i386__) || defined(__x86_64__)
 
-extern int ichspi_lock;
-
 static int enable_flash_ali_m1533(struct pci_dev *dev, const char *name)
 {
 	uint8_t tmp;
@@ -515,8 +513,9 @@
 			msg_pdbg("0x%02x: 0x%08x (SPID%d+4)\n", offs + 4,
 				     mmio_readl(spibar + offs + 4), i);
 		}
+		ichspi_bbar = mmio_readl(spibar + 0x50);
 		msg_pdbg("0x50: 0x%08x (BBAR)\n",
-			     mmio_readl(spibar + 0x50));
+			     ichspi_bbar);
 		msg_pdbg("0x54: 0x%04x     (PREOP)\n",
 			     mmio_readw(spibar + 0x54));
 		msg_pdbg("0x56: 0x%04x     (OPTYPE)\n",
@@ -587,8 +586,9 @@
 			     mmio_readl(spibar + 0x98));
 		msg_pdbg("0x9C: 0x%08x (OPMENU+4)\n",
 			     mmio_readl(spibar + 0x9C));
+		ichspi_bbar = mmio_readl(spibar + 0xA0);
 		msg_pdbg("0xA0: 0x%08x (BBAR)\n",
-			     mmio_readl(spibar + 0xA0));
+			     ichspi_bbar);
 		msg_pdbg("0xB0: 0x%08x (FDOC)\n",
 			     mmio_readl(spibar + 0xB0));
 		if (tmp2 & (1 << 15)) {
diff --git a/flash.h b/flash.h
index a201af3..ec7dd8e 100644
--- a/flash.h
+++ b/flash.h
@@ -663,6 +663,8 @@
 uint32_t spi_get_valid_read_addr(void);
 
 /* ichspi.c */
+extern int ichspi_lock;
+extern uint32_t ichspi_bbar;
 int ich_init_opcodes(void);
 int ich_spi_send_command(unsigned int writecnt, unsigned int readcnt,
 		    const unsigned char *writearr, unsigned char *readarr);
diff --git a/ichspi.c b/ichspi.c
index e9a3611..76a61d2 100644
--- a/ichspi.c
+++ b/ichspi.c
@@ -103,6 +103,8 @@
 /* ICH SPI configuration lock-down. May be set during chipset enabling. */
 int ichspi_lock = 0;
 
+uint32_t ichspi_bbar = 0;
+
 typedef struct _OPCODE {
 	uint8_t opcode;		//This commands spi opcode
 	uint8_t spi_type;	//This commands spi type
@@ -327,6 +329,34 @@
 	return 0;
 }
 
+/*
+ * Try to set BBAR (BIOS Base Address Register), but read back the value in case
+ * it didn't stick.
+ */
+void ich_set_bbar(uint32_t minaddr)
+{
+	switch (spi_controller) {
+	case SPI_CONTROLLER_ICH7:
+		mmio_writel(minaddr, spibar + 0x50);
+		ichspi_bbar = mmio_readl(spibar + 0x50);
+		/* We don't have any option except complaining. */
+		if (ichspi_bbar != minaddr)
+			msg_perr("Setting BBAR failed!\n");
+		break;
+	case SPI_CONTROLLER_ICH9:
+		mmio_writel(minaddr, spibar + 0xA0);
+		ichspi_bbar = mmio_readl(spibar + 0xA0);
+		/* We don't have any option except complaining. */
+		if (ichspi_bbar != minaddr)
+			msg_perr("Setting BBAR failed!\n");
+		break;
+	default:
+		/* Not sure if BBAR actually exists on VIA. */
+		msg_pdbg("Setting BBAR is not implemented for VIA yet.\n");
+		break;
+	}
+}
+
 /* This function generates OPCODES from or programs OPCODES to ICH according to
  * the chipset's SPI configuration lock.
  *
@@ -341,13 +371,18 @@
 		return 0;
 
 	if (ichspi_lock) {
-		msg_pdbg("Generating OPCODES... ");
+		msg_pdbg("Reading OPCODES... ");
 		curopcodes_done = &O_EXISTING;
 		rc = generate_opcodes(curopcodes_done);
 	} else {
 		msg_pdbg("Programming OPCODES... ");
 		curopcodes_done = &O_ST_M25P;
 		rc = program_opcodes(curopcodes_done);
+		/* Technically not part of opcode init, but it allows opcodes
+		 * to run without transaction errors by setting the lowest
+		 * allowed address to zero.
+		 */
+		ich_set_bbar(0);
 	}
 
 	if (rc) {
@@ -743,6 +778,19 @@
 	    opcode->spi_type == SPI_OPCODE_TYPE_WRITE_WITH_ADDRESS) {
 		addr = (writearr[1] << 16) |
 		    (writearr[2] << 8) | (writearr[3] << 0);
+		switch (spi_controller) {
+		case SPI_CONTROLLER_ICH7:
+		case SPI_CONTROLLER_ICH9:
+			if (addr < ichspi_bbar) {
+				msg_perr("%s: Address 0x%06x below allowed "
+					 "range 0x%06x-0xffffff\n", __func__,
+					 addr, ichspi_bbar);
+				return SPI_INVALID_ADDRESS;
+			}
+			break;
+		default:
+			break;
+		}
 	}
 
 	/* translate read/write array/count */
diff --git a/spi.c b/spi.c
index 24696fb..0d501c0 100644
--- a/spi.c
+++ b/spi.c
@@ -207,8 +207,22 @@
 	return spi_programmer[spi_controller].write_256(flash, buf);
 }
 
+/*
+ * Get the lowest allowed address for read accesses. This often happens to
+ * be the lowest allowed address for all commands which take an address.
+ * This is a programmer limitation.
+ */
 uint32_t spi_get_valid_read_addr(void)
 {
-	/* Need to return BBAR for ICH chipsets. */
-	return 0;
+	switch (spi_controller) {
+#if INTERNAL_SUPPORT == 1
+#if defined(__i386__) || defined(__x86_64__)
+	case SPI_CONTROLLER_ICH7:
+		/* Return BBAR for ICH chipsets. */
+		return ichspi_bbar;
+#endif
+#endif
+	default:
+		return 0;
+	}
 }