diff --git a/arch/powerpc/sysdev/indirect_pci.c b/arch/powerpc/sysdev/indirect_pci.c
index cfbd2aae93e8a178e665242f415894b34fce3b41..7fd49c97501aa965058a12d9b62f484fdde0cc56 100644
--- a/arch/powerpc/sysdev/indirect_pci.c
+++ b/arch/powerpc/sysdev/indirect_pci.c
@@ -123,6 +123,12 @@ indirect_write_config(struct pci_bus *bus, unsigned int devfn, int offset,
 			(bus->number == hose->first_busno))
 		val &= 0xffffff00;
 
+	/* Workaround for PCI_28 Errata in 440EPx/GRx */
+	if ((hose->indirect_type & PPC_INDIRECT_TYPE_BROKEN_MRM) &&
+			offset == PCI_CACHE_LINE_SIZE) {
+		val = 0;
+	}
+
 	/*
 	 * Note: the caller has already checked that offset is
 	 * suitably aligned and that len is 1, 2 or 4.
diff --git a/arch/powerpc/sysdev/ppc4xx_pci.c b/arch/powerpc/sysdev/ppc4xx_pci.c
index 76886cf0e6dc305b17ee1a4d6e1585b6cdc9f5ad..fb368dfde5d472403a67c33ec88d8cde55beec6f 100644
--- a/arch/powerpc/sysdev/ppc4xx_pci.c
+++ b/arch/powerpc/sysdev/ppc4xx_pci.c
@@ -75,6 +75,11 @@ static void fixup_ppc4xx_pci_bridge(struct pci_dev *dev)
 	    !of_device_is_compatible(hose->dn, "ibm,plb-pci"))
 		return;
 
+	if (of_device_is_compatible(hose->dn, "ibm,plb440epx-pci") ||
+		of_device_is_compatible(hose->dn, "ibm,plb440grx-pci")) {
+		hose->indirect_type |= PPC_INDIRECT_TYPE_BROKEN_MRM;
+	}
+
 	/* Hide the PCI host BARs from the kernel as their content doesn't
 	 * fit well in the resource management
 	 */
diff --git a/include/asm-powerpc/pci-bridge.h b/include/asm-powerpc/pci-bridge.h
index b95d033ae6e60eceabac04fbe3432b5f2f630d9a..ae2ea803a0f2502daff6e2ffcd24359c1f602675 100644
--- a/include/asm-powerpc/pci-bridge.h
+++ b/include/asm-powerpc/pci-bridge.h
@@ -92,12 +92,15 @@ struct pci_controller {
 	 *   anything but the PHB.  Only allow talking to the PHB if this is
 	 *   set.
 	 *  BIG_ENDIAN - cfg_addr is a big endian register
+	 *  BROKEN_MRM - the 440EPx/GRx chips have an errata that causes hangs on
+	 *   the PLB4.  Effectively disable MRM commands by setting this.
 	 */
 #define PPC_INDIRECT_TYPE_SET_CFG_TYPE		0x00000001
 #define PPC_INDIRECT_TYPE_EXT_REG		0x00000002
 #define PPC_INDIRECT_TYPE_SURPRESS_PRIMARY_BUS	0x00000004
 #define PPC_INDIRECT_TYPE_NO_PCIE_LINK		0x00000008
 #define PPC_INDIRECT_TYPE_BIG_ENDIAN		0x00000010
+#define PPC_INDIRECT_TYPE_BROKEN_MRM		0x00000020
 	u32 indirect_type;
 #endif	/* !CONFIG_PPC64 */
 	/* Currently, we limit ourselves to 1 IO range and 3 mem