[RFC PATCH v2] edac: synopsys: Added EDAC support for zynq ddr ecc controller

Punnaiah Choudary Kalluri punnaiah.choudary.kalluri at xilinx.com
Mon Mar 17 01:23:44 EDT 2014


Added EDAC support for reporting the ecc errors of synopsys ddr controller.
The ddr ecc controller corrects single bit errors and detects double bit
errors

Signed-off-by: Punnaiah Choudary Kalluri <punnaia at xilinx.com>
---
Changes for v2:
- Updated the commit header and message
- Renamed the filenames to synopsys_edac
- Corrected the compatilble string, commnets
- Renamed the macros,fucntions and data structures
---
 .../devicetree/bindings/edac/synopsys_edac.txt     |   18 +
 drivers/edac/Kconfig                               |    7 +
 drivers/edac/Makefile                              |    1 +
 drivers/edac/synopsys_edac.c                       |  614 ++++++++++++++++++++
 4 files changed, 640 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/edac/synopsys_edac.txt
 create mode 100644 drivers/edac/synopsys_edac.c

diff --git a/Documentation/devicetree/bindings/edac/synopsys_edac.txt b/Documentation/devicetree/bindings/edac/synopsys_edac.txt
new file mode 100644
index 0000000..c4a559b
--- /dev/null
+++ b/Documentation/devicetree/bindings/edac/synopsys_edac.txt
@@ -0,0 +1,18 @@
+Synopsys EDAC driver, it does reports the DDR ECC single bit errors that are
+corrected and double bit ecc errors that are detected by the DDR ECC controller.
+ECC support for DDR is available in half-bus width(16 bit) configuration only.
+
+Required properties:
+- compatible: Should be "xlnx,zynq-ddrc-1.04"
+- reg: Should contain DDR controller registers location and length.
+
+Example:
+++++++++
+
+ddrc0: ddrc at f8006000 {
+	compatible = "xlnx,zynq-ddrc-1.04";
+	reg = <0xf8006000 0x1000>;
+};
+
+Synopsys EDAC driver detects the DDR ECC enable state by reading the appropriate
+control register.
diff --git a/drivers/edac/Kconfig b/drivers/edac/Kconfig
index 878f090..58b69b1 100644
--- a/drivers/edac/Kconfig
+++ b/drivers/edac/Kconfig
@@ -368,4 +368,11 @@ config EDAC_OCTEON_PCI
 	  Support for error detection and correction on the
 	  Cavium Octeon family of SOCs.
 
+config EDAC_SYNOPSYS
+	tristate "Synopsys DDR Memory Controller"
+	depends on EDAC_MM_EDAC && ARCH_ZYNQ
+	help
+	  This enables support for EDAC on the ECC memory used
+	  with the Synopsys DDR memory controller.
+
 endif # EDAC
diff --git a/drivers/edac/Makefile b/drivers/edac/Makefile
index 4154ed6..5628a6f 100644
--- a/drivers/edac/Makefile
+++ b/drivers/edac/Makefile
@@ -64,3 +64,4 @@ obj-$(CONFIG_EDAC_OCTEON_PC)		+= octeon_edac-pc.o
 obj-$(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_SYNOPSYS)		+= synopsys_edac.o
diff --git a/drivers/edac/synopsys_edac.c b/drivers/edac/synopsys_edac.c
new file mode 100644
index 0000000..7cec331
--- /dev/null
+++ b/drivers/edac/synopsys_edac.c
@@ -0,0 +1,614 @@
+/*
+ * Synopsys DDR ECC Driver
+ * This driver is based on ppc4xx_edac.c drivers
+ *
+ * Copyright (C) 2012 - 2014 Xilinx, Inc.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that 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/edac.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#include "edac_core.h"
+
+/* Number of cs_rows needed per memory controller */
+#define SYNOPSYS_EDAC_NR_CSROWS	1
+
+/* Number of channels per memory controller */
+#define SYNOPSYS_EDAC_NR_CHANS	1
+
+/* Granularity of reported error in bytes */
+#define SYNOPSYS_EDAC_ERROR_GRAIN	1
+
+#define SYNOPSYS_EDAC_MESSAGE_SIZE	256
+
+/* Synopsys DDR memory controller registers that are relevant to ECC */
+#define SYNOPSYS_DDRC_CONTROL_REG_OFFSET	0x0 /* Control regsieter */
+#define SYNOPSYS_DDRC_T_ZQ_REG_OFFSET	0xA4 /* ZQ register */
+
+/* ECC control register */
+#define SYNOPSYS_DDRC_ECC_CONTROL_REG_OFFSET	0xC4
+/* ECC log register */
+#define SYNOPSYS_DDRC_ECC_CE_LOG_REG_OFFSET		0xC8
+/* ECC address register */
+#define SYNOPSYS_DDRC_ECC_CE_ADDR_REG_OFFSET	0xCC
+/* ECC data[31:0] register */
+#define SYNOPSYS_DDRC_ECC_CE_DATA_31_0_REG_OFFSET	0xD0
+
+/* Uncorrectable error info regsisters */
+#define SYNOPSYS_DDRC_ECC_UE_LOG_REG_OFFSET	0xDC /* ECC log register */
+#define SYNOPSYS_DDRC_ECC_UE_ADDR_REG_OFFSET	0xE0 /* ECC address register */
+#define SYNOPSYS_DDRC_ECC_UE_DATA_31_0_REG_OFFSET	0xE4 /* ECC data reg */
+
+#define SYNOPSYS_DDRC_ECC_STAT_REG_OFFSET	0xF0 /* ECC stats register */
+#define SYNOPSYS_DDRC_ECC_SCRUB_REG_OFFSET	0xF4 /* ECC scrub register */
+
+/* Control regsiter bitfield definitions */
+#define SYNOPSYS_DDRC_CTRLREG_BUSWIDTH_MASK	0xC
+#define SYNOPSYS_DDRC_CTRLREG_BUSWIDTH_SHIFT	2
+
+#define SYNOPSYS_DDRCTL_WDTH_16	1
+#define SYNOPSYS_DDRCTL_WDTH_32	0
+
+/* ZQ register bitfield definitions */
+#define SYNOPSYS_DDRC_T_ZQ_REG_DDRMODE_MASK	0x2
+
+/* ECC control register bitfield definitions */
+#define SYNOPSYS_DDRC_ECCCTRL_CLR_CE_ERR	0x2
+#define SYNOPSYS_DDRC_ECCCTRL_CLR_UE_ERR	0x1
+
+/* ECC correctable/uncorrectable error log register definitions */
+#define SYNOPSYS_DDRC_ECC_CE_LOGREG_VALID		0x1
+#define SYNOPSYS_DDRC_ECC_CE_LOGREG_BITPOS_MASK		0xFE
+#define SYNOPSYS_DDRC_ECC_CE_LOGREG_BITPOS_SHIFT	1
+
+/* ECC correctable/uncorrectable error address register definitions */
+#define SYNOPSYS_DDRC_ECC_ADDRREG_COL_MASK		0xFFF
+#define SYNOPSYS_DDRC_ECC_ADDRREG_ROW_MASK		0xFFFF000
+#define SYNOPSYS_DDRC_ECC_ADDRREG_ROW_SHIFT		12
+#define SYNOPSYS_DDRC_ECC_ADDRREG_BANK_MASK		0x70000000
+#define SYNOPSYS_DDRC_ECC_ADDRREG_BANK_SHIFT	28
+
+/* ECC statistic regsiter definitions */
+#define SYNOPSYS_DDRC_ECC_STATREG_UECOUNT_MASK	0xFF
+#define SYNOPSYS_DDRC_ECC_STATREG_CECOUNT_MASK	0xFF00
+#define SYNOPSYS_DDRC_ECC_STATREG_CECOUNT_SHIFT	8
+
+/* ECC scrub regsiter definitions */
+#define SYNOPSYS_DDRC_ECC_SCRUBREG_ECC_MODE_MASK	0x7
+#define SYNOPSYS_DDRC_ECC_SCRUBREG_ECCMODE_SECDED	0x4
+
+/**
+ * struct ecc_error_info - ECC error log information
+ * @row:	Row number
+ * @col:	Column number
+ * @bank:	Bank number
+ * @bitpos:	Bit position
+ * @data:	Data causing the error
+ */
+struct ecc_error_info {
+	u32 row;
+	u32 col;
+	u32 bank;
+	u32 bitpos;
+	u32 data;
+};
+
+/**
+ * struct synopsys_ecc_status - ECC status information to report
+ * @ce_count:	Correctable error count
+ * @ue_count:	Uncorrectable error count
+ * @ceinfo:	Correctable error log information
+ * @ueinfo:	Uncorrectable error log information
+ */
+struct synopsys_ecc_status {
+	u32 ce_count;
+	u32 ue_count;
+	struct ecc_error_info ceinfo;
+	struct ecc_error_info ueinfo;
+};
+
+/**
+ * struct synopsys_edac_priv - DDR memory controller private instance data
+ * @baseaddr:		Base address of the DDR controller
+ * @ce_count:		Correctable Error count
+ * @ue_count:		Uncorrectable Error count
+ */
+struct synopsys_edac_priv {
+	void __iomem *baseaddr;
+	u32 ce_count;
+	u32 ue_count;
+};
+
+/**
+ * synopsys_edac_geterror_info - Get the current ecc error info
+ * @base:	Pointer to the base address of the ddr memory controller
+ * @perrstatus:	Pointer to the synopsys ecc status structure
+ *
+ * This routine determines there is any ecc error or not
+ *
+ * Return: zero if there is no error otherwise returns 1
+ */
+static int synopsys_edac_geterror_info(void __iomem *base,
+		struct synopsys_ecc_status *perrstatus)
+{
+	u32 regval;
+	u32 clearval = 0;
+
+	regval = readl(base + SYNOPSYS_DDRC_ECC_STAT_REG_OFFSET) &
+			(SYNOPSYS_DDRC_ECC_STATREG_UECOUNT_MASK |
+			SYNOPSYS_DDRC_ECC_STATREG_CECOUNT_MASK);
+
+	if (regval == 0)
+		return 0;
+
+	memset(perrstatus, 0, sizeof(struct synopsys_ecc_status));
+
+	perrstatus->ce_count =
+			   (regval & SYNOPSYS_DDRC_ECC_STATREG_CECOUNT_MASK) >>
+			    SYNOPSYS_DDRC_ECC_STATREG_CECOUNT_SHIFT;
+	perrstatus->ue_count =
+			   (regval & SYNOPSYS_DDRC_ECC_STATREG_UECOUNT_MASK);
+
+	if (perrstatus->ce_count) {
+		regval = readl(base + SYNOPSYS_DDRC_ECC_CE_LOG_REG_OFFSET);
+		if (regval & SYNOPSYS_DDRC_ECC_CE_LOGREG_VALID) {
+			perrstatus->ceinfo.bitpos = (regval &
+				SYNOPSYS_DDRC_ECC_CE_LOGREG_BITPOS_MASK) >>
+				SYNOPSYS_DDRC_ECC_CE_LOGREG_BITPOS_SHIFT;
+			regval = readl(base +
+					SYNOPSYS_DDRC_ECC_CE_ADDR_REG_OFFSET);
+			perrstatus->ceinfo.row = (regval &
+					SYNOPSYS_DDRC_ECC_ADDRREG_ROW_MASK) >>
+					SYNOPSYS_DDRC_ECC_ADDRREG_ROW_SHIFT;
+			perrstatus->ceinfo.col = (regval &
+					SYNOPSYS_DDRC_ECC_ADDRREG_COL_MASK);
+			perrstatus->ceinfo.bank = (regval &
+					SYNOPSYS_DDRC_ECC_ADDRREG_BANK_MASK) >>
+					SYNOPSYS_DDRC_ECC_ADDRREG_BANK_SHIFT;
+			perrstatus->ceinfo.data = readl(base +
+				SYNOPSYS_DDRC_ECC_CE_DATA_31_0_REG_OFFSET);
+			edac_dbg(3, "ce bitposition: %d data: %d\n",
+					perrstatus->ceinfo.bitpos,
+					perrstatus->ceinfo.data);
+		}
+		clearval = SYNOPSYS_DDRC_ECCCTRL_CLR_CE_ERR;
+	}
+
+	if (perrstatus->ue_count) {
+		regval = readl(base + SYNOPSYS_DDRC_ECC_UE_LOG_REG_OFFSET);
+		if (regval & SYNOPSYS_DDRC_ECC_CE_LOGREG_VALID) {
+			regval = readl(base +
+					SYNOPSYS_DDRC_ECC_UE_ADDR_REG_OFFSET);
+			perrstatus->ueinfo.row = (regval &
+					SYNOPSYS_DDRC_ECC_ADDRREG_ROW_MASK) >>
+					SYNOPSYS_DDRC_ECC_ADDRREG_ROW_SHIFT;
+			perrstatus->ueinfo.col = (regval &
+					SYNOPSYS_DDRC_ECC_ADDRREG_COL_MASK);
+			perrstatus->ueinfo.bank = (regval &
+					SYNOPSYS_DDRC_ECC_ADDRREG_BANK_MASK) >>
+					SYNOPSYS_DDRC_ECC_ADDRREG_BANK_SHIFT;
+			perrstatus->ueinfo.data = readl(base +
+				    SYNOPSYS_DDRC_ECC_UE_DATA_31_0_REG_OFFSET);
+		}
+		clearval |= SYNOPSYS_DDRC_ECCCTRL_CLR_UE_ERR;
+	}
+
+	writel(clearval, base + SYNOPSYS_DDRC_ECC_CONTROL_REG_OFFSET);
+	writel(0x0, base + SYNOPSYS_DDRC_ECC_CONTROL_REG_OFFSET);
+
+	return 1;
+}
+
+/**
+ * synopsys_edac_generate_message - Generate interpreted ECC status message
+ * @mci:	Pointer to the edac memory controller instance
+ * @perrstatus:	Pointer to the synopsys ecc status structure
+ * @buffer:	Pointer to the buffer in which to generate the
+ *		message
+ * @size:	The size, in bytes, of space available in buffer
+ *
+ * This routine generates to the provided buffer the portion of the
+ * driver-unique report message associated with the ECC register of
+ * the specified ECC status.
+ */
+static void synopsys_edac_generate_message(const struct mem_ctl_info *mci,
+			struct synopsys_ecc_status *perrstatus, char *buffer,
+			size_t size)
+{
+	struct ecc_error_info *pinfo = NULL;
+
+	if (perrstatus->ce_count > 0)
+		pinfo = &perrstatus->ceinfo;
+	else
+		pinfo = &perrstatus->ueinfo;
+
+	snprintf(buffer, SYNOPSYS_EDAC_MESSAGE_SIZE,
+		 "DDR ECC error type :%s Row %d Bank %d Col %d ",
+		 (perrstatus->ce_count > 0) ? "CE" : "UE", pinfo->row,
+		 pinfo->bank, pinfo->col);
+}
+
+/**
+ * synopsys_edac_handle_error - Handle controller error types CE and UE
+ * @mci:	Pointer to the edac memory controller instance
+ * @perrstatus:	Pointer to the synopsys ecc status structure
+ *
+ * This routine handles the controller ECC correctable error.
+ */
+static void synopsys_edac_handle_error(struct mem_ctl_info *mci,
+			struct synopsys_ecc_status *perrstatus)
+{
+	char message[SYNOPSYS_EDAC_MESSAGE_SIZE];
+
+	synopsys_edac_generate_message(mci, perrstatus, &message[0],
+				   SYNOPSYS_EDAC_MESSAGE_SIZE);
+
+	if (perrstatus->ce_count)
+		edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci,
+				     perrstatus->ce_count, 0, 0, 0, 0, 0, -1,
+				     &message[0], "");
+	else
+		edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci,
+				     perrstatus->ue_count, 0, 0, 0, 0, 0, -1,
+				     &message[0], "");
+}
+
+/**
+ * synopsys_edac_check - Check controller for ECC errors
+ * @mci:	Pointer to the edac memory controller instance
+ *
+ * This routine is used to check and post ECC errors and is called by
+ * the EDAC polling thread
+ */
+static void synopsys_edac_check(struct mem_ctl_info *mci)
+{
+	struct synopsys_edac_priv *priv = mci->pvt_info;
+	struct synopsys_ecc_status errstatus;
+	int status;
+
+	status = synopsys_edac_geterror_info(priv->baseaddr, &errstatus);
+	if (status) {
+		priv->ce_count += errstatus.ce_count;
+		priv->ue_count += errstatus.ue_count;
+
+		if (errstatus.ce_count) {
+			synopsys_edac_handle_error(mci, &errstatus);
+			errstatus.ce_count = 0;
+		}
+		if (errstatus.ue_count) {
+			synopsys_edac_handle_error(mci, &errstatus);
+			errstatus.ue_count = 0;
+		}
+		edac_dbg(3, "total error count ce %d ue %d\n",
+			 priv->ce_count, priv->ue_count);
+	}
+}
+
+/**
+ * synopsys_edac_get_dtype - Return the controller memory width
+ * @base:	Pointer to the ddr memory contoller base address
+ *
+ * This routine returns the EDAC device type width appropriate for the
+ * current controller configuration.
+ *
+ * Return: a device type width enumeration.
+ */
+static enum dev_type synopsys_edac_get_dtype(void __iomem *base)
+{
+	enum dev_type dt;
+	u32 width;
+
+	width = readl(base + SYNOPSYS_DDRC_CONTROL_REG_OFFSET);
+	width = (width & SYNOPSYS_DDRC_CTRLREG_BUSWIDTH_MASK) >>
+			SYNOPSYS_DDRC_CTRLREG_BUSWIDTH_SHIFT;
+
+	switch (width) {
+	case SYNOPSYS_DDRCTL_WDTH_16:
+		dt = DEV_X2;
+		break;
+	case SYNOPSYS_DDRCTL_WDTH_32:
+		dt = DEV_X4;
+		break;
+	default:
+		dt = DEV_UNKNOWN;
+	}
+
+	return dt;
+}
+
+/**
+ * synopsys_edac_get_eccstate - Return the controller ecc enable/disable status
+ * @base:	Pointer to the ddr memory contoller base address
+ *
+ * This routine returns the ECC enable/diable status for the controller
+ *
+ * Return: a ecc status boolean i.e true/false - enabled/disabled.
+ */
+static bool synopsys_edac_get_eccstate(void __iomem *base)
+{
+	enum dev_type dt;
+	u32 ecctype;
+	bool state = false;
+
+	dt = synopsys_edac_get_dtype(base);
+
+	ecctype = (readl(base + SYNOPSYS_DDRC_ECC_SCRUB_REG_OFFSET) &
+			SYNOPSYS_DDRC_ECC_SCRUBREG_ECC_MODE_MASK);
+
+	if ((ecctype == SYNOPSYS_DDRC_ECC_SCRUBREG_ECCMODE_SECDED)
+			&& (dt == DEV_X2)) {
+		state = true;
+		writel(0x0, base + SYNOPSYS_DDRC_ECC_CONTROL_REG_OFFSET);
+	} else {
+		state = false;
+	}
+
+	return state;
+}
+
+/**
+ * synopsys_edac_get_memsize - reads the size of the attached memory device
+ *
+ * Return: the memory size in bytes
+ *
+ * This routine returns the size of the system memory by reading the sysinfo
+ * information
+ */
+static u32 synopsys_edac_get_memsize(void)
+{
+	struct sysinfo inf;
+
+	/* Reading the system memory size from the global meminfo structure */
+	si_meminfo(&inf);
+
+	return inf.totalram * inf.mem_unit;
+}
+
+/**
+ * synopsys_edac_get_mtype - Returns controller memory type
+ * @base:	pointer to the synopsys ecc status structure
+ *
+ * This routine returns the EDAC memory type appropriate for the
+ * current controller configuration.
+ *
+ * Return: a memory type enumeration.
+ */
+static enum mem_type synopsys_edac_get_mtype(void __iomem *base)
+{
+	enum mem_type mt;
+	u32 memtype;
+
+	memtype = readl(base + SYNOPSYS_DDRC_T_ZQ_REG_OFFSET);
+
+	if (memtype & SYNOPSYS_DDRC_T_ZQ_REG_DDRMODE_MASK)
+		mt = MEM_DDR3;
+	else
+		mt = MEM_DDR2;
+
+	return mt;
+}
+
+/**
+ * synopsys_edac_init_csrows - Initialize the cs row data
+ * @mci:	Pointer to the edac memory controller instance
+ *
+ * This routine initializes the chip select rows associated
+ * with the EDAC memory controller instance
+ *
+ * Return: 0 if OK; otherwise, -EINVAL if the memory bank size
+ * configuration cannot be determined.
+ */
+static int synopsys_edac_init_csrows(struct mem_ctl_info *mci)
+{
+	struct csrow_info *csi;
+	struct dimm_info *dimm;
+	struct synopsys_edac_priv *priv = mci->pvt_info;
+	u32 size;
+	int row, j;
+
+	for (row = 0; row < mci->nr_csrows; row++) {
+		csi = mci->csrows[row];
+		size = synopsys_edac_get_memsize();
+
+		for (j = 0; j < csi->nr_channels; j++) {
+			dimm = csi->channels[j]->dimm;
+			dimm->edac_mode = EDAC_FLAG_SECDED;
+			dimm->mtype = synopsys_edac_get_mtype(priv->baseaddr);
+			dimm->nr_pages =
+			    (size >> PAGE_SHIFT) / csi->nr_channels;
+			dimm->grain = SYNOPSYS_EDAC_ERROR_GRAIN;
+			dimm->dtype = synopsys_edac_get_dtype(priv->baseaddr);
+		}
+
+	}
+
+	return 0;
+}
+
+/**
+ * synopsys_edac_mc_init - Initialize driver instance
+ * @mci:	Pointer to the edac memory controller instance
+ * @pdev:	Pointer to the platform_device struct
+ *
+ * This routine performs initialization of the EDAC memory controller
+ * instance and related driver-private data associated with the
+ * memory controller the instance is bound to.
+ *
+ * Return: 0 if OK; otherwise, < 0 on error.
+ */
+static int synopsys_edac_mc_init(struct mem_ctl_info *mci,
+			struct platform_device *pdev)
+{
+	int status;
+	struct synopsys_edac_priv *priv;
+
+	/* Initial driver pointers and private data */
+	mci->pdev = &pdev->dev;
+	priv = mci->pvt_info;
+	platform_set_drvdata(pdev, mci);
+
+	/* Initialize controller capabilities and configuration */
+	mci->mtype_cap = MEM_FLAG_DDR3 | MEM_FLAG_DDR2;
+	mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_SECDED;
+	mci->scrub_cap = SCRUB_HW_SRC;
+	/* Check the scrub setting from the controller */
+	mci->scrub_mode = SCRUB_NONE;
+
+	mci->edac_cap = EDAC_FLAG_SECDED;
+	/* Initialize strings */
+	mci->ctl_name = "synopsys_ddr_controller";
+	mci->dev_name = dev_name(&pdev->dev);
+	mci->mod_name = "synopsys_edac";
+	mci->mod_ver = "1";
+
+	/* Initialize callbacks */
+	edac_op_state = EDAC_OPSTATE_POLL;
+	mci->edac_check = synopsys_edac_check;
+	mci->ctl_page_to_phys = NULL;
+
+	/*
+	 * Initialize the MC control structure 'csrows' table
+	 * with the mapping and control information.
+	 */
+	status = synopsys_edac_init_csrows(mci);
+	if (status)
+		pr_err("Failed to initialize rows!\n");
+
+	return status;
+}
+
+/**
+ * synopsys_edac_mc_probe - Check controller and bind driver
+ * @pdev:	Pointer to the platform_device struct
+ *
+ * This routine probes a specific controller
+ * instance for binding with the driver.
+ *
+ * Return: 0 if the controller instance was successfully bound to the
+ * driver; otherwise, < 0 on error.
+ */
+static int synopsys_edac_mc_probe(struct platform_device *pdev)
+{
+	struct mem_ctl_info *mci;
+	struct edac_mc_layer layers[2];
+	struct synopsys_edac_priv *priv;
+	int rc;
+	struct resource *res;
+	void __iomem *baseaddr;
+
+	/* Get the data from the platform device */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	baseaddr = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(baseaddr))
+		return PTR_ERR(baseaddr);
+
+	/* Check for the ecc enable status */
+	if (synopsys_edac_get_eccstate(baseaddr) == false) {
+		dev_err(&pdev->dev, "ecc not enabled\n");
+		return -ENXIO;
+	}
+
+	/*
+	 * At this point, we know ECC is enabled, allocate an EDAC
+	 * controller instance and perform the appropriate
+	 * initialization.
+	 */
+	layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
+	layers[0].size = SYNOPSYS_EDAC_NR_CSROWS;
+	layers[0].is_virt_csrow = true;
+	layers[1].type = EDAC_MC_LAYER_CHANNEL;
+	layers[1].size = SYNOPSYS_EDAC_NR_CHANS;
+	layers[1].is_virt_csrow = false;
+
+	mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers,
+			    sizeof(struct synopsys_edac_priv));
+	if (mci == NULL) {
+		pr_err("Failed memory allocation for mci instance!\n");
+		return -ENOMEM;
+	}
+
+	priv = mci->pvt_info;
+	priv->baseaddr = baseaddr;
+	rc = synopsys_edac_mc_init(mci, pdev);
+	if (rc) {
+		pr_err("Failed to initialize instance!\n");
+		goto free_edac_mc;
+	}
+
+	/*
+	 * We have a valid, initialized EDAC instance bound to the
+	 * controller. Attempt to register it with the EDAC subsystem
+	 */
+	rc = edac_mc_add_mc(mci);
+	if (rc) {
+		dev_err(&pdev->dev, "failed to register with EDAC core\n");
+		goto del_edac_mc;
+	}
+
+	return rc;
+
+del_edac_mc:
+	edac_mc_del_mc(&pdev->dev);
+free_edac_mc:
+	edac_mc_free(mci);
+
+	return rc;
+}
+
+/**
+ * synopsys_edac_mc_remove - Unbind driver from controller
+ * @pdev:	Pointer to the platform_device struct
+ *
+ * This routine unbinds the EDAC memory controller instance associated
+ * with the specified controller described by the
+ * OpenFirmware device tree node passed as a parameter.
+ *
+ * Return: Unconditionally 0
+ */
+static int synopsys_edac_mc_remove(struct platform_device *pdev)
+{
+	struct mem_ctl_info *mci = platform_get_drvdata(pdev);
+
+	edac_mc_del_mc(&pdev->dev);
+	edac_mc_free(mci);
+
+	return 0;
+}
+
+/* Device tree node type and compatible tuples this driver can match on */
+static struct of_device_id synopsys_edac_match[] = {
+	{ .compatible = "xlnx,zynq-ddrc-1.04", },
+	{ /* end of table */ }
+};
+
+MODULE_DEVICE_TABLE(of, synopsys_edac_match);
+
+static struct platform_driver synopsys_edac_mc_driver = {
+	.driver = {
+		   .name = "synopsys-edac",
+		   .owner = THIS_MODULE,
+		   .of_match_table = synopsys_edac_match,
+		   },
+	.probe = synopsys_edac_mc_probe,
+	.remove = synopsys_edac_mc_remove,
+};
+
+module_platform_driver(synopsys_edac_mc_driver);
+
+MODULE_AUTHOR("Xilinx, Inc.");
+MODULE_DESCRIPTION("Synopsys DDR ECC driver");
+MODULE_LICENSE("GPL v2");
-- 
1.7.4





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