Merge tag 'edac_for_4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp

Pull EDAC updates from Borislav Petkov:

 - Altera: L2 cache and On-Chip RAM support (Thor Thayer).

 - EDAC: Workqueue handling cleanups (Borislav Petkov).

 - Xgene: Register bus error handling (Loc Ho).

 - Misc small fixes.

* tag 'edac_for_4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp:
  ARM: socfpga: Enable OCRAM ECC on startup
  ARM: socfpga: Enable L2 cache ECC on startup
  ARM: dts: Add Altera L2 Cache and OCRAM EDAC entries
  EDAC, altera: Add Altera L2 cache and OCRAM support
  EDAC: Use edac_debugfs_remove_recursive() in edac_debugfs_exit()
  EDAC, mpc85xx: Silence unused variable warning
  EDAC: Cleanup/sync workqueue functions
  EDAC: Kill workqueue setup/teardown functions
  EDAC: Balance workqueue setup and teardown
  arm64: Update the APM X-Gene EDAC node with the RB register resource
  EDAC, xgene: Add missing SoC register bus error handling
  Documentation, EDAC: Update xgene binding for missing register bus
  EDAC, amd64_edac: Shift wrapping issue in f1x_get_norm_dct_addr()

Documentation/devicetree/bindings/arm/altera/socfpga-eccmgr.txt

+Altera SoCFPGA ECC Manager
+This driver uses the EDAC framework to implement the SOCFPGA ECC Manager.
+The ECC Manager counts and corrects single bit errors and counts/handles
+double bit errors which are uncorrectable.
+
+Required Properties:
+- compatible : Should be "altr,socfpga-ecc-manager"
+- #address-cells: must be 1
+- #size-cells: must be 1
+- ranges : standard definition, should translate from local addresses
+
+Subcomponents:
+
+L2 Cache ECC
+Required Properties:
+- compatible : Should be "altr,socfpga-l2-ecc"
+- reg : Address and size for ECC error interrupt clear registers.
+- interrupts : Should be single bit error interrupt, then double bit error
+	interrupt. Note the rising edge type.
+
+On Chip RAM ECC
+Required Properties:
+- compatible : Should be "altr,socfpga-ocram-ecc"
+- reg : Address and size for ECC error interrupt clear registers.
+- iram : phandle to On-Chip RAM definition.
+- interrupts : Should be single bit error interrupt, then double bit error
+	interrupt. Note the rising edge type.
+
+Example:
+
+	eccmgr: eccmgr@ffd08140 {
+		compatible = "altr,socfpga-ecc-manager";
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges;
+
+		l2-ecc@ffd08140 {
+			compatible = "altr,socfpga-l2-ecc";
+			reg = <0xffd08140 0x4>;
+			interrupts = <0 36 1>, <0 37 1>;
+		};
+
+		ocram-ecc@ffd08144 {
+			compatible = "altr,socfpga-ocram-ecc";
+			reg = <0xffd08144 0x4>;
+			iram = <&ocram>;
+			interrupts = <0 178 1>, <0 179 1>;
+		};
+	};

Documentation/devicetree/bindings/edac/apm-xgene-edac.txt

@@ -16,6 +16,10 @@ Required properties:
 - regmap-mcba		: Regmap of the MCB-A (memory bridge) resource.
 - regmap-mcbb		: Regmap of the MCB-B (memory bridge) resource.
 - regmap-efuse		: Regmap of the PMD efuse resource.
+- regmap-rb		: Regmap of the register bus resource. This property
+			  is optional only for compatibility. If the RB
+			  error conditions are not cleared, it will
+			  continuously generate interrupt.
 - reg			: First resource shall be the CPU bus (PCP) resource.
 - interrupts            : Interrupt-specifier for MCU, PMD, L3, or SoC error
 			  IRQ(s).
@@ -64,6 +68,11 @@ Example:
 		reg = <0x0 0x1054a000 0x0 0x20>;
 	};
 
+	rb: rb@7e000000 {
+		compatible = "apm,xgene-rb", "syscon";
+		reg = <0x0 0x7e000000 0x0 0x10>;
+	};
+
 	edac@78800000 {
 		compatible = "apm,xgene-edac";
 		#address-cells = <2>;
@@ -73,6 +82,7 @@ Example:
 		regmap-mcba = <&mcba>;
 		regmap-mcbb = <&mcbb>;
 		regmap-efuse = <&efuse>;
+		regmap-rb = <&rb>;
 		reg = <0x0 0x78800000 0x0 0x100>;
 		interrupts = <0x0 0x20 0x4>,
 			     <0x0 0x21 0x4>,

arch/arm/boot/dts/socfpga.dtsi

@@ -656,6 +656,26 @@ i2c3: i2c@ffc07000 {
 			status = "disabled";
 		};
 
+		eccmgr: eccmgr@ffd08140 {
+			compatible = "altr,socfpga-ecc-manager";
+			#address-cells = <1>;
+			#size-cells = <1>;
+			ranges;
+
+			l2-ecc@ffd08140 {
+				compatible = "altr,socfpga-l2-ecc";
+				reg = <0xffd08140 0x4>;
+				interrupts = <0 36 1>, <0 37 1>;
+			};
+
+			ocram-ecc@ffd08144 {
+				compatible = "altr,socfpga-ocram-ecc";
+				reg = <0xffd08144 0x4>;
+				iram = <&ocram>;
+				interrupts = <0 178 1>, <0 179 1>;
+			};
+		};
+
 		L2: l2-cache@fffef000 {
 			compatible = "arm,pl310-cache";
 			reg = <0xfffef000 0x1000>;

arch/arm/mach-socfpga/Makefile

@@ -5,3 +5,5 @@
 obj-y					:= socfpga.o
 obj-$(CONFIG_SMP)	+= headsmp.o platsmp.o
 obj-$(CONFIG_SOCFPGA_SUSPEND)	+= pm.o self-refresh.o
+obj-$(CONFIG_EDAC_ALTERA_L2C)	+= l2_cache.o
+obj-$(CONFIG_EDAC_ALTERA_OCRAM)	+= ocram.o

arch/arm/mach-socfpga/core.h

@@ -36,6 +36,8 @@
 
 extern void socfpga_init_clocks(void);
 extern void socfpga_sysmgr_init(void);
+void socfpga_init_l2_ecc(void);
+void socfpga_init_ocram_ecc(void);
 
 extern void __iomem *sys_manager_base_addr;
 extern void __iomem *rst_manager_base_addr;

arch/arm/mach-socfpga/l2_cache.c

+/*
+ * Copyright Altera Corporation (C) 2016. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <linux/io.h>
+#include <linux/of_platform.h>
+#include <linux/of_address.h>
+
+void socfpga_init_l2_ecc(void)
+{
+	struct device_node *np;
+	void __iomem *mapped_l2_edac_addr;
+
+	np = of_find_compatible_node(NULL, NULL, "altr,socfpga-l2-ecc");
+	if (!np) {
+		pr_err("Unable to find socfpga-l2-ecc in dtb\n");
+		return;
+	}
+
+	mapped_l2_edac_addr = of_iomap(np, 0);
+	of_node_put(np);
+	if (!mapped_l2_edac_addr) {
+		pr_err("Unable to find L2 ECC mapping in dtb\n");
+		return;
+	}
+
+	/* Enable ECC */
+	writel(0x01, mapped_l2_edac_addr);
+	iounmap(mapped_l2_edac_addr);
+}

arch/arm/mach-socfpga/ocram.c

+/*
+ * Copyright Altera Corporation (C) 2016. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <linux/io.h>
+#include <linux/genalloc.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+
+#define ALTR_OCRAM_CLEAR_ECC          0x00000018
+#define ALTR_OCRAM_ECC_EN             0x00000019
+
+void socfpga_init_ocram_ecc(void)
+{
+	struct device_node *np;
+	void __iomem *mapped_ocr_edac_addr;
+
+	/* Find the OCRAM EDAC device tree node */
+	np = of_find_compatible_node(NULL, NULL, "altr,socfpga-ocram-ecc");
+	if (!np) {
+		pr_err("Unable to find socfpga-ocram-ecc\n");
+		return;
+	}
+
+	mapped_ocr_edac_addr = of_iomap(np, 0);
+	of_node_put(np);
+	if (!mapped_ocr_edac_addr) {
+		pr_err("Unable to map OCRAM ecc regs.\n");
+		return;
+	}
+
+	/* Clear any pending OCRAM ECC interrupts, then enable ECC */
+	writel(ALTR_OCRAM_CLEAR_ECC, mapped_ocr_edac_addr);
+	writel(ALTR_OCRAM_ECC_EN, mapped_ocr_edac_addr);
+
+	iounmap(mapped_ocr_edac_addr);
+}

arch/arm/mach-socfpga/socfpga.c

@@ -59,6 +59,11 @@ static void __init socfpga_init_irq(void)
 {
 	irqchip_init();
 	socfpga_sysmgr_init();
+	if (IS_ENABLED(CONFIG_EDAC_ALTERA_L2C))
+		socfpga_init_l2_ecc();
+
+	if (IS_ENABLED(CONFIG_EDAC_ALTERA_OCRAM))
+		socfpga_init_ocram_ecc();
 }
 
 static void socfpga_cyclone5_restart(enum reboot_mode mode, const char *cmd)

arch/arm64/boot/dts/apm/apm-storm.dtsi

@@ -493,6 +493,11 @@ efuse: efuse@1054a000 {
 			reg = <0x0 0x1054a000 0x0 0x20>;
 		};
 
+		rb: rb@7e000000 {
+			compatible = "apm,xgene-rb", "syscon";
+			reg = <0x0 0x7e000000 0x0 0x10>;
+		};
+
 		edac@78800000 {
 			compatible = "apm,xgene-edac";
 			#address-cells = <2>;
@@ -502,6 +507,7 @@ edac@78800000 {
 			regmap-mcba = <&mcba>;
 			regmap-mcbb = <&mcbb>;
 			regmap-efuse = <&efuse>;
+			regmap-rb = <&rb>;
 			reg = <0x0 0x78800000 0x0 0x100>;
 			interrupts = <0x0 0x20 0x4>,
 				     <0x0 0x21 0x4>,

drivers/edac/Kconfig

@@ -367,14 +367,30 @@ config EDAC_OCTEON_PCI
 	  Support for error detection and correction on the
 	  Cavium Octeon family of SOCs.
 
-config EDAC_ALTERA_MC
-	bool "Altera SDRAM Memory Controller EDAC"
+config EDAC_ALTERA
+	bool "Altera SOCFPGA ECC"
 	depends on EDAC_MM_EDAC=y && ARCH_SOCFPGA
 	help
 	  Support for error detection and correction on the
-	  Altera SDRAM memory controller. Note that the
-	  preloader must initialize the SDRAM before loading
-	  the kernel.
+	  Altera SOCs. This must be selected for SDRAM ECC.
+	  Note that the preloader must initialize the SDRAM
+	  before loading the kernel.
+
+config EDAC_ALTERA_L2C
+	bool "Altera L2 Cache ECC"
+	depends on EDAC_ALTERA=y
+	select CACHE_L2X0
+	help
+	  Support for error detection and correction on the
+	  Altera L2 cache Memory for Altera SoCs. This option
+	  requires L2 cache so it will force that selection.
+
+config EDAC_ALTERA_OCRAM
+	bool "Altera On-Chip RAM ECC"
+	depends on EDAC_ALTERA=y && SRAM && GENERIC_ALLOCATOR
+	help
+	  Support for error detection and correction on the
+	  Altera On-Chip RAM Memory for Altera SoCs.
 
 config EDAC_SYNOPSYS
 	tristate "Synopsys DDR Memory Controller"

drivers/edac/Makefile

@@ -67,6 +67,6 @@ obj-$(CONFIG_EDAC_OCTEON_L2C)		+= octeon_edac-l2c.o
 obj-$(CONFIG_EDAC_OCTEON_LMC)		+= octeon_edac-lmc.o
 obj-$(CONFIG_EDAC_OCTEON_PCI)		+= octeon_edac-pci.o
 
-obj-$(CONFIG_EDAC_ALTERA_MC)		+= altera_edac.o
+obj-$(CONFIG_EDAC_ALTERA)		+= altera_edac.o
 obj-$(CONFIG_EDAC_SYNOPSYS)		+= synopsys_edac.o
 obj-$(CONFIG_EDAC_XGENE)		+= xgene_edac.o

drivers/edac/amd64_edac.c

@@ -1452,7 +1452,7 @@ static u64 f1x_get_norm_dct_addr(struct amd64_pvt *pvt, u8 range,
 	u64 chan_off;
 	u64 dram_base		= get_dram_base(pvt, range);
 	u64 hole_off		= f10_dhar_offset(pvt);
-	u64 dct_sel_base_off	= (pvt->dct_sel_hi & 0xFFFFFC00) << 16;
+	u64 dct_sel_base_off	= (u64)(pvt->dct_sel_hi & 0xFFFFFC00) << 16;
 
 	if (hi_rng) {
 		/*

drivers/edac/debugfs.c

@@ -53,7 +53,7 @@ int __init edac_debugfs_init(void)
 
 void edac_debugfs_exit(void)
 {
-	debugfs_remove(edac_debugfs);
+	debugfs_remove_recursive(edac_debugfs);
 }
 
 int edac_create_debugfs_nodes(struct mem_ctl_info *mci)

drivers/edac/edac_mc.c

@@ -535,59 +535,20 @@ static void edac_mc_workq_function(struct work_struct *work_req)
 
 	mutex_lock(&mem_ctls_mutex);
 
-	/* if this control struct has movd to offline state, we are done */
-	if (mci->op_state == OP_OFFLINE) {
+	if (mci->op_state != OP_RUNNING_POLL) {
 		mutex_unlock(&mem_ctls_mutex);
 		return;
 	}
 
-	/* Only poll controllers that are running polled and have a check */
-	if (edac_mc_assert_error_check_and_clear() && (mci->edac_check != NULL))
+	if (edac_mc_assert_error_check_and_clear())
 		mci->edac_check(mci);
 
 	mutex_unlock(&mem_ctls_mutex);
 
-	/* Reschedule */
+	/* Queue ourselves again. */
 	edac_queue_work(&mci->work, msecs_to_jiffies(edac_mc_get_poll_msec()));
 }
 
-/*
- * edac_mc_workq_setup
- *	initialize a workq item for this mci
- *	passing in the new delay period in msec
- *
- *	locking model:
- *
- *		called with the mem_ctls_mutex held
- */
-static void edac_mc_workq_setup(struct mem_ctl_info *mci, unsigned msec)
-{
-	edac_dbg(0, "\n");
-
-	/* if this instance is not in the POLL state, then simply return */
-	if (mci->op_state != OP_RUNNING_POLL)
-		return;
-
-	INIT_DELAYED_WORK(&mci->work, edac_mc_workq_function);
-
-	edac_queue_work(&mci->work, msecs_to_jiffies(msec));
-}
-
-/*
- * edac_mc_workq_teardown
- *	stop the workq processing on this mci
- *
- *	locking model:
- *
- *		called WITHOUT lock held
- */
-static void edac_mc_workq_teardown(struct mem_ctl_info *mci)
-{
-	mci->op_state = OP_OFFLINE;
-
-	edac_stop_work(&mci->work);
-}
-
 /*
  * edac_mc_reset_delay_period(unsigned long value)
  *
@@ -771,12 +732,12 @@ int edac_mc_add_mc_with_groups(struct mem_ctl_info *mci,
 		goto fail1;
 	}
 
-	/* If there IS a check routine, then we are running POLLED */
-	if (mci->edac_check != NULL) {
-		/* This instance is NOW RUNNING */
+	if (mci->edac_check) {
 		mci->op_state = OP_RUNNING_POLL;
 
-		edac_mc_workq_setup(mci, edac_mc_get_poll_msec());
+		INIT_DELAYED_WORK(&mci->work, edac_mc_workq_function);
+		edac_queue_work(&mci->work, msecs_to_jiffies(edac_mc_get_poll_msec()));
+
 	} else {
 		mci->op_state = OP_RUNNING_INTERRUPT;
 	}
@@ -823,15 +784,16 @@ struct mem_ctl_info *edac_mc_del_mc(struct device *dev)
 		return NULL;
 	}
 
+	/* mark MCI offline: */
+	mci->op_state = OP_OFFLINE;
+
 	if (!del_mc_from_global_list(mci))
 		edac_mc_owner = NULL;
-	mutex_unlock(&mem_ctls_mutex);
 
-	/* flush workq processes */
-	edac_mc_workq_teardown(mci);
+	mutex_unlock(&mem_ctls_mutex);
 
-	/* marking MCI offline */
-	mci->op_state = OP_OFFLINE;
+	if (mci->edac_check)
+		edac_stop_work(&mci->work);
 
 	/* remove from sysfs */
 	edac_remove_sysfs_mci_device(mci);

drivers/edac/edac_pci.c

@@ -195,55 +195,24 @@ static void edac_pci_workq_function(struct work_struct *work_req)
 
 	mutex_lock(&edac_pci_ctls_mutex);
 
-	if (pci->op_state == OP_RUNNING_POLL) {
-		/* we might be in POLL mode, but there may NOT be a poll func
-		 */
-		if ((pci->edac_check != NULL) && edac_pci_get_check_errors())
-			pci->edac_check(pci);
-
-		/* if we are on a one second period, then use round */
-		msec = edac_pci_get_poll_msec();
-		if (msec == 1000)
-			delay = round_jiffies_relative(msecs_to_jiffies(msec));
-		else
-			delay = msecs_to_jiffies(msec);
-
-		/* Reschedule only if we are in POLL mode */
-		edac_queue_work(&pci->work, delay);
+	if (pci->op_state != OP_RUNNING_POLL) {
+		mutex_unlock(&edac_pci_ctls_mutex);
+		return;
 	}
 
-	mutex_unlock(&edac_pci_ctls_mutex);
-}
-
-/*
- * edac_pci_workq_setup()
- * 	initialize a workq item for this edac_pci instance
- * 	passing in the new delay period in msec
- *
- *	locking model:
- *		called when 'edac_pci_ctls_mutex' is locked
- */
-static void edac_pci_workq_setup(struct edac_pci_ctl_info *pci,
-				 unsigned int msec)
-{
-	edac_dbg(0, "\n");
+	if (edac_pci_get_check_errors())
+		pci->edac_check(pci);
 
-	INIT_DELAYED_WORK(&pci->work, edac_pci_workq_function);
+	/* if we are on a one second period, then use round */
+	msec = edac_pci_get_poll_msec();
+	if (msec == 1000)
+		delay = round_jiffies_relative(msecs_to_jiffies(msec));
+	else
+		delay = msecs_to_jiffies(msec);
 
-	edac_queue_work(&pci->work, msecs_to_jiffies(edac_pci_get_poll_msec()));
-}
+	edac_queue_work(&pci->work, delay);
 
-/*
- * edac_pci_workq_teardown()
- * 	stop the workq processing on this edac_pci instance
- */
-static void edac_pci_workq_teardown(struct edac_pci_ctl_info *pci)
-{
-	edac_dbg(0, "\n");
-
-	pci->op_state = OP_OFFLINE;
-
-	edac_stop_work(&pci->work);
+	mutex_unlock(&edac_pci_ctls_mutex);
 }
 
 /*
@@ -289,10 +258,12 @@ int edac_pci_add_device(struct edac_pci_ctl_info *pci, int edac_idx)
 		goto fail1;
 	}
 
-	if (pci->edac_check != NULL) {
+	if (pci->edac_check) {
 		pci->op_state = OP_RUNNING_POLL;
 
-		edac_pci_workq_setup(pci, 1000);
+		INIT_DELAYED_WORK(&pci->work, edac_pci_workq_function);
+		edac_queue_work(&pci->work, msecs_to_jiffies(edac_pci_get_poll_msec()));
+
 	} else {
 		pci->op_state = OP_RUNNING_INTERRUPT;
 	}
@@ -350,8 +321,8 @@ struct edac_pci_ctl_info *edac_pci_del_device(struct device *dev)
 
 	mutex_unlock(&edac_pci_ctls_mutex);
 
-	/* stop the workq timer */
-	edac_pci_workq_teardown(pci);
+	if (pci->edac_check)
+		edac_stop_work(&pci->work);
 
 	edac_printk(KERN_INFO, EDAC_PCI,
 		"Removed device %d for %s %s: DEV %s\n",

drivers/edac/mpc85xx_edac.c

@@ -1244,7 +1244,7 @@ static struct platform_driver * const drivers[] = {
 static int __init mpc85xx_mc_init(void)
 {
 	int res = 0;
-	u32 pvr = 0;
+	u32 __maybe_unused pvr = 0;
 
 	printk(KERN_INFO "Freescale(R) MPC85xx EDAC driver, "
 	       "(C) 2006 Montavista Software\n");

drivers/edac/xgene_edac.c

@@ -61,6 +61,7 @@ struct xgene_edac {
 	struct regmap		*mcba_map;
 	struct regmap		*mcbb_map;
 	struct regmap		*efuse_map;
+	struct regmap		*rb_map;
 	void __iomem		*pcp_csr;
 	spinlock_t		lock;
 	struct dentry           *dfs;
@@ -1057,7 +1058,7 @@ static bool xgene_edac_l3_promote_to_uc_err(u32 l3cesr, u32 l3celr)
 		case 0x041:
 			return true;
 		}
-	} else if (L3C_ELR_ERRSYN(l3celr) == 9)
+	} else if (L3C_ELR_ERRWAY(l3celr) == 9)
 		return true;
 
 	return false;
@@ -1353,6 +1354,17 @@ static int xgene_edac_l3_remove(struct xgene_edac_dev_ctx *l3)
 #define GLBL_MDED_ERRH			0x0848
 #define GLBL_MDED_ERRHMASK		0x084c
 
+/* IO Bus Registers */
+#define RBCSR				0x0000
+#define STICKYERR_MASK			BIT(0)
+#define RBEIR				0x0008
+#define AGENT_OFFLINE_ERR_MASK		BIT(30)
+#define UNIMPL_RBPAGE_ERR_MASK		BIT(29)
+#define WORD_ALIGNED_ERR_MASK		BIT(28)
+#define PAGE_ACCESS_ERR_MASK		BIT(27)
+#define WRITE_ACCESS_MASK		BIT(26)
+#define RBERRADDR_RD(src)		((src) & 0x03FFFFFF)
+
 static const char * const soc_mem_err_v1[] = {
 	"10GbE0",
 	"10GbE1",
@@ -1470,6 +1482,51 @@ static void xgene_edac_rb_report(struct edac_device_ctl_info *edac_dev)
 	u32 err_addr_hi;
 	u32 reg;
 
+	/* If the register bus resource isn't available, just skip it */
+	if (!ctx->edac->rb_map)
+		goto rb_skip;
+
+	/*
+	 * Check RB access errors
+	 * 1. Out of range
+	 * 2. Un-implemented page
+	 * 3. Un-aligned access
+	 * 4. Offline slave IP
+	 */
+	if (regmap_read(ctx->edac->rb_map, RBCSR, &reg))
+		return;
+	if (reg & STICKYERR_MASK) {
+		bool write;
+		u32 address;
+
+		dev_err(edac_dev->dev, "IOB bus access error(s)\n");
+		if (regmap_read(ctx->edac->rb_map, RBEIR, &reg))
+			return;
+		write = reg & WRITE_ACCESS_MASK ? 1 : 0;
+		address = RBERRADDR_RD(reg);
+		if (reg & AGENT_OFFLINE_ERR_MASK)
+			dev_err(edac_dev->dev,
+				"IOB bus %s access to offline agent error\n",
+				write ? "write" : "read");
+		if (reg & UNIMPL_RBPAGE_ERR_MASK)
+			dev_err(edac_dev->dev,
+				"IOB bus %s access to unimplemented page error\n",
+				write ? "write" : "read");
+		if (reg & WORD_ALIGNED_ERR_MASK)
+			dev_err(edac_dev->dev,
+				"IOB bus %s word aligned access error\n",
+				write ? "write" : "read");
+		if (reg & PAGE_ACCESS_ERR_MASK)
+			dev_err(edac_dev->dev,
+				"IOB bus %s to page out of range access error\n",
+				write ? "write" : "read");
+		if (regmap_write(ctx->edac->rb_map, RBEIR, 0))
+			return;
+		if (regmap_write(ctx->edac->rb_map, RBCSR, 0))
+			return;
+	}
+rb_skip:
+
 	/* IOB Bridge agent transaction error interrupt */
 	reg = readl(ctx->dev_csr + IOBBATRANSERRINTSTS);
 	if (!reg)
@@ -1852,6 +1909,17 @@ static int xgene_edac_probe(struct platform_device *pdev)
 		goto out_err;
 	}
 
+	/*
+	 * NOTE: The register bus resource is optional for compatibility
+	 * reason.
+	 */
+	edac->rb_map = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
+						       "regmap-rb");
+	if (IS_ERR(edac->rb_map)) {
+		dev_warn(edac->dev, "missing syscon regmap rb\n");
+		edac->rb_map = NULL;
+	}
+
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	edac->pcp_csr = devm_ioremap_resource(&pdev->dev, res);
 	if (IS_ERR(edac->pcp_csr)) {