EDAC, fsl-ddr: Separate FSL DDR driver from MPC85xx

The mpc85xx-compatible DDR controllers are used on ARM-based SoCs too.
Carve out the DDR part from the mpc85xx EDAC driver in preparation to
support both architectures.

Signed-off-by: York Sun <york.sun@nxp.com>
Cc: Johannes Thumshirn <morbidrsa@gmail.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: oss@buserror.net
Cc: stuart.yoder@nxp.com
Link: http://lkml.kernel.org/r/1470946525-3410-1-git-send-email-york.sun@nxp.com
Signed-off-by: Borislav Petkov <bp@suse.de>
diff --git a/drivers/edac/fsl_ddr_edac.c b/drivers/edac/fsl_ddr_edac.c
new file mode 100644
index 0000000..ca7636f
--- /dev/null
+++ b/drivers/edac/fsl_ddr_edac.c
@@ -0,0 +1,592 @@
+/*
+ * Freescale Memory Controller kernel module
+ *
+ * Support Power-based SoCs including MPC85xx, MPC86xx, MPC83xx and
+ * ARM-based Layerscape SoCs including LS2xxx. Originally split
+ * out from mpc85xx_edac EDAC driver.
+ *
+ * Parts Copyrighted (c) 2013 by Freescale Semiconductor, Inc.
+ *
+ * Author: Dave Jiang <djiang@mvista.com>
+ *
+ * 2006-2007 (c) MontaVista Software, Inc. This file is licensed under
+ * the terms of the GNU General Public License version 2. This program
+ * is licensed "as is" without any warranty of any kind, whether express
+ * or implied.
+ *
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/ctype.h>
+#include <linux/io.h>
+#include <linux/mod_devicetable.h>
+#include <linux/edac.h>
+#include <linux/smp.h>
+#include <linux/gfp.h>
+
+#include <linux/of_platform.h>
+#include <linux/of_device.h>
+#include "edac_module.h"
+#include "edac_core.h"
+#include "fsl_ddr_edac.h"
+
+#define EDAC_MOD_STR	"fsl_ddr_edac"
+
+static int edac_mc_idx;
+
+static u32 orig_ddr_err_disable;
+static u32 orig_ddr_err_sbe;
+
+/************************ MC SYSFS parts ***********************************/
+
+#define to_mci(k) container_of(k, struct mem_ctl_info, dev)
+
+static ssize_t mpc85xx_mc_inject_data_hi_show(struct device *dev,
+					      struct device_attribute *mattr,
+					      char *data)
+{
+	struct mem_ctl_info *mci = to_mci(dev);
+	struct mpc85xx_mc_pdata *pdata = mci->pvt_info;
+	return sprintf(data, "0x%08x",
+		       in_be32(pdata->mc_vbase +
+			       MPC85XX_MC_DATA_ERR_INJECT_HI));
+}
+
+static ssize_t mpc85xx_mc_inject_data_lo_show(struct device *dev,
+					      struct device_attribute *mattr,
+					      char *data)
+{
+	struct mem_ctl_info *mci = to_mci(dev);
+	struct mpc85xx_mc_pdata *pdata = mci->pvt_info;
+	return sprintf(data, "0x%08x",
+		       in_be32(pdata->mc_vbase +
+			       MPC85XX_MC_DATA_ERR_INJECT_LO));
+}
+
+static ssize_t mpc85xx_mc_inject_ctrl_show(struct device *dev,
+					   struct device_attribute *mattr,
+					   char *data)
+{
+	struct mem_ctl_info *mci = to_mci(dev);
+	struct mpc85xx_mc_pdata *pdata = mci->pvt_info;
+	return sprintf(data, "0x%08x",
+		       in_be32(pdata->mc_vbase + MPC85XX_MC_ECC_ERR_INJECT));
+}
+
+static ssize_t mpc85xx_mc_inject_data_hi_store(struct device *dev,
+					       struct device_attribute *mattr,
+					       const char *data, size_t count)
+{
+	struct mem_ctl_info *mci = to_mci(dev);
+	struct mpc85xx_mc_pdata *pdata = mci->pvt_info;
+	if (isdigit(*data)) {
+		out_be32(pdata->mc_vbase + MPC85XX_MC_DATA_ERR_INJECT_HI,
+			 simple_strtoul(data, NULL, 0));
+		return count;
+	}
+	return 0;
+}
+
+static ssize_t mpc85xx_mc_inject_data_lo_store(struct device *dev,
+					       struct device_attribute *mattr,
+					       const char *data, size_t count)
+{
+	struct mem_ctl_info *mci = to_mci(dev);
+	struct mpc85xx_mc_pdata *pdata = mci->pvt_info;
+	if (isdigit(*data)) {
+		out_be32(pdata->mc_vbase + MPC85XX_MC_DATA_ERR_INJECT_LO,
+			 simple_strtoul(data, NULL, 0));
+		return count;
+	}
+	return 0;
+}
+
+static ssize_t mpc85xx_mc_inject_ctrl_store(struct device *dev,
+					       struct device_attribute *mattr,
+					       const char *data, size_t count)
+{
+	struct mem_ctl_info *mci = to_mci(dev);
+	struct mpc85xx_mc_pdata *pdata = mci->pvt_info;
+	if (isdigit(*data)) {
+		out_be32(pdata->mc_vbase + MPC85XX_MC_ECC_ERR_INJECT,
+			 simple_strtoul(data, NULL, 0));
+		return count;
+	}
+	return 0;
+}
+
+DEVICE_ATTR(inject_data_hi, S_IRUGO | S_IWUSR,
+	    mpc85xx_mc_inject_data_hi_show, mpc85xx_mc_inject_data_hi_store);
+DEVICE_ATTR(inject_data_lo, S_IRUGO | S_IWUSR,
+	    mpc85xx_mc_inject_data_lo_show, mpc85xx_mc_inject_data_lo_store);
+DEVICE_ATTR(inject_ctrl, S_IRUGO | S_IWUSR,
+	    mpc85xx_mc_inject_ctrl_show, mpc85xx_mc_inject_ctrl_store);
+
+static struct attribute *mpc85xx_dev_attrs[] = {
+	&dev_attr_inject_data_hi.attr,
+	&dev_attr_inject_data_lo.attr,
+	&dev_attr_inject_ctrl.attr,
+	NULL
+};
+
+ATTRIBUTE_GROUPS(mpc85xx_dev);
+
+/**************************** MC Err device ***************************/
+
+/*
+ * Taken from table 8-55 in the MPC8641 User's Manual and/or 9-61 in the
+ * MPC8572 User's Manual.  Each line represents a syndrome bit column as a
+ * 64-bit value, but split into an upper and lower 32-bit chunk.  The labels
+ * below correspond to Freescale's manuals.
+ */
+static unsigned int ecc_table[16] = {
+	/* MSB           LSB */
+	/* [0:31]    [32:63] */
+	0xf00fe11e, 0xc33c0ff7,	/* Syndrome bit 7 */
+	0x00ff00ff, 0x00fff0ff,
+	0x0f0f0f0f, 0x0f0fff00,
+	0x11113333, 0x7777000f,
+	0x22224444, 0x8888222f,
+	0x44448888, 0xffff4441,
+	0x8888ffff, 0x11118882,
+	0xffff1111, 0x22221114,	/* Syndrome bit 0 */
+};
+
+/*
+ * Calculate the correct ECC value for a 64-bit value specified by high:low
+ */
+static u8 calculate_ecc(u32 high, u32 low)
+{
+	u32 mask_low;
+	u32 mask_high;
+	int bit_cnt;
+	u8 ecc = 0;
+	int i;
+	int j;
+
+	for (i = 0; i < 8; i++) {
+		mask_high = ecc_table[i * 2];
+		mask_low = ecc_table[i * 2 + 1];
+		bit_cnt = 0;
+
+		for (j = 0; j < 32; j++) {
+			if ((mask_high >> j) & 1)
+				bit_cnt ^= (high >> j) & 1;
+			if ((mask_low >> j) & 1)
+				bit_cnt ^= (low >> j) & 1;
+		}
+
+		ecc |= bit_cnt << i;
+	}
+
+	return ecc;
+}
+
+/*
+ * Create the syndrome code which is generated if the data line specified by
+ * 'bit' failed.  Eg generate an 8-bit codes seen in Table 8-55 in the MPC8641
+ * User's Manual and 9-61 in the MPC8572 User's Manual.
+ */
+static u8 syndrome_from_bit(unsigned int bit) {
+	int i;
+	u8 syndrome = 0;
+
+	/*
+	 * Cycle through the upper or lower 32-bit portion of each value in
+	 * ecc_table depending on if 'bit' is in the upper or lower half of
+	 * 64-bit data.
+	 */
+	for (i = bit < 32; i < 16; i += 2)
+		syndrome |= ((ecc_table[i] >> (bit % 32)) & 1) << (i / 2);
+
+	return syndrome;
+}
+
+/*
+ * Decode data and ecc syndrome to determine what went wrong
+ * Note: This can only decode single-bit errors
+ */
+static void sbe_ecc_decode(u32 cap_high, u32 cap_low, u32 cap_ecc,
+		       int *bad_data_bit, int *bad_ecc_bit)
+{
+	int i;
+	u8 syndrome;
+
+	*bad_data_bit = -1;
+	*bad_ecc_bit = -1;
+
+	/*
+	 * Calculate the ECC of the captured data and XOR it with the captured
+	 * ECC to find an ECC syndrome value we can search for
+	 */
+	syndrome = calculate_ecc(cap_high, cap_low) ^ cap_ecc;
+
+	/* Check if a data line is stuck... */
+	for (i = 0; i < 64; i++) {
+		if (syndrome == syndrome_from_bit(i)) {
+			*bad_data_bit = i;
+			return;
+		}
+	}
+
+	/* If data is correct, check ECC bits for errors... */
+	for (i = 0; i < 8; i++) {
+		if ((syndrome >> i) & 0x1) {
+			*bad_ecc_bit = i;
+			return;
+		}
+	}
+}
+
+#define make64(high, low) (((u64)(high) << 32) | (low))
+
+static void mpc85xx_mc_check(struct mem_ctl_info *mci)
+{
+	struct mpc85xx_mc_pdata *pdata = mci->pvt_info;
+	struct csrow_info *csrow;
+	u32 bus_width;
+	u32 err_detect;
+	u32 syndrome;
+	u64 err_addr;
+	u32 pfn;
+	int row_index;
+	u32 cap_high;
+	u32 cap_low;
+	int bad_data_bit;
+	int bad_ecc_bit;
+
+	err_detect = in_be32(pdata->mc_vbase + MPC85XX_MC_ERR_DETECT);
+	if (!err_detect)
+		return;
+
+	mpc85xx_mc_printk(mci, KERN_ERR, "Err Detect Register: %#8.8x\n",
+			  err_detect);
+
+	/* no more processing if not ECC bit errors */
+	if (!(err_detect & (DDR_EDE_SBE | DDR_EDE_MBE))) {
+		out_be32(pdata->mc_vbase + MPC85XX_MC_ERR_DETECT, err_detect);
+		return;
+	}
+
+	syndrome = in_be32(pdata->mc_vbase + MPC85XX_MC_CAPTURE_ECC);
+
+	/* Mask off appropriate bits of syndrome based on bus width */
+	bus_width = (in_be32(pdata->mc_vbase + MPC85XX_MC_DDR_SDRAM_CFG) &
+			DSC_DBW_MASK) ? 32 : 64;
+	if (bus_width == 64)
+		syndrome &= 0xff;
+	else
+		syndrome &= 0xffff;
+
+	err_addr = make64(
+		in_be32(pdata->mc_vbase + MPC85XX_MC_CAPTURE_EXT_ADDRESS),
+		in_be32(pdata->mc_vbase + MPC85XX_MC_CAPTURE_ADDRESS));
+	pfn = err_addr >> PAGE_SHIFT;
+
+	for (row_index = 0; row_index < mci->nr_csrows; row_index++) {
+		csrow = mci->csrows[row_index];
+		if ((pfn >= csrow->first_page) && (pfn <= csrow->last_page))
+			break;
+	}
+
+	cap_high = in_be32(pdata->mc_vbase + MPC85XX_MC_CAPTURE_DATA_HI);
+	cap_low = in_be32(pdata->mc_vbase + MPC85XX_MC_CAPTURE_DATA_LO);
+
+	/*
+	 * Analyze single-bit errors on 64-bit wide buses
+	 * TODO: Add support for 32-bit wide buses
+	 */
+	if ((err_detect & DDR_EDE_SBE) && (bus_width == 64)) {
+		sbe_ecc_decode(cap_high, cap_low, syndrome,
+				&bad_data_bit, &bad_ecc_bit);
+
+		if (bad_data_bit != -1)
+			mpc85xx_mc_printk(mci, KERN_ERR,
+				"Faulty Data bit: %d\n", bad_data_bit);
+		if (bad_ecc_bit != -1)
+			mpc85xx_mc_printk(mci, KERN_ERR,
+				"Faulty ECC bit: %d\n", bad_ecc_bit);
+
+		mpc85xx_mc_printk(mci, KERN_ERR,
+			"Expected Data / ECC:\t%#8.8x_%08x / %#2.2x\n",
+			cap_high ^ (1 << (bad_data_bit - 32)),
+			cap_low ^ (1 << bad_data_bit),
+			syndrome ^ (1 << bad_ecc_bit));
+	}
+
+	mpc85xx_mc_printk(mci, KERN_ERR,
+			"Captured Data / ECC:\t%#8.8x_%08x / %#2.2x\n",
+			cap_high, cap_low, syndrome);
+	mpc85xx_mc_printk(mci, KERN_ERR, "Err addr: %#8.8llx\n", err_addr);
+	mpc85xx_mc_printk(mci, KERN_ERR, "PFN: %#8.8x\n", pfn);
+
+	/* we are out of range */
+	if (row_index == mci->nr_csrows)
+		mpc85xx_mc_printk(mci, KERN_ERR, "PFN out of range!\n");
+
+	if (err_detect & DDR_EDE_SBE)
+		edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, 1,
+				     pfn, err_addr & ~PAGE_MASK, syndrome,
+				     row_index, 0, -1,
+				     mci->ctl_name, "");
+
+	if (err_detect & DDR_EDE_MBE)
+		edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci, 1,
+				     pfn, err_addr & ~PAGE_MASK, syndrome,
+				     row_index, 0, -1,
+				     mci->ctl_name, "");
+
+	out_be32(pdata->mc_vbase + MPC85XX_MC_ERR_DETECT, err_detect);
+}
+
+static irqreturn_t mpc85xx_mc_isr(int irq, void *dev_id)
+{
+	struct mem_ctl_info *mci = dev_id;
+	struct mpc85xx_mc_pdata *pdata = mci->pvt_info;
+	u32 err_detect;
+
+	err_detect = in_be32(pdata->mc_vbase + MPC85XX_MC_ERR_DETECT);
+	if (!err_detect)
+		return IRQ_NONE;
+
+	mpc85xx_mc_check(mci);
+
+	return IRQ_HANDLED;
+}
+
+static void mpc85xx_init_csrows(struct mem_ctl_info *mci)
+{
+	struct mpc85xx_mc_pdata *pdata = mci->pvt_info;
+	struct csrow_info *csrow;
+	struct dimm_info *dimm;
+	u32 sdram_ctl;
+	u32 sdtype;
+	enum mem_type mtype;
+	u32 cs_bnds;
+	int index;
+
+	sdram_ctl = in_be32(pdata->mc_vbase + MPC85XX_MC_DDR_SDRAM_CFG);
+
+	sdtype = sdram_ctl & DSC_SDTYPE_MASK;
+	if (sdram_ctl & DSC_RD_EN) {
+		switch (sdtype) {
+		case DSC_SDTYPE_DDR:
+			mtype = MEM_RDDR;
+			break;
+		case DSC_SDTYPE_DDR2:
+			mtype = MEM_RDDR2;
+			break;
+		case DSC_SDTYPE_DDR3:
+			mtype = MEM_RDDR3;
+			break;
+		default:
+			mtype = MEM_UNKNOWN;
+			break;
+		}
+	} else {
+		switch (sdtype) {
+		case DSC_SDTYPE_DDR:
+			mtype = MEM_DDR;
+			break;
+		case DSC_SDTYPE_DDR2:
+			mtype = MEM_DDR2;
+			break;
+		case DSC_SDTYPE_DDR3:
+			mtype = MEM_DDR3;
+			break;
+		default:
+			mtype = MEM_UNKNOWN;
+			break;
+		}
+	}
+
+	for (index = 0; index < mci->nr_csrows; index++) {
+		u32 start;
+		u32 end;
+
+		csrow = mci->csrows[index];
+		dimm = csrow->channels[0]->dimm;
+
+		cs_bnds = in_be32(pdata->mc_vbase + MPC85XX_MC_CS_BNDS_0 +
+				  (index * MPC85XX_MC_CS_BNDS_OFS));
+
+		start = (cs_bnds & 0xffff0000) >> 16;
+		end   = (cs_bnds & 0x0000ffff);
+
+		if (start == end)
+			continue;	/* not populated */
+
+		start <<= (24 - PAGE_SHIFT);
+		end   <<= (24 - PAGE_SHIFT);
+		end    |= (1 << (24 - PAGE_SHIFT)) - 1;
+
+		csrow->first_page = start;
+		csrow->last_page = end;
+
+		dimm->nr_pages = end + 1 - start;
+		dimm->grain = 8;
+		dimm->mtype = mtype;
+		dimm->dtype = DEV_UNKNOWN;
+		if (sdram_ctl & DSC_X32_EN)
+			dimm->dtype = DEV_X32;
+		dimm->edac_mode = EDAC_SECDED;
+	}
+}
+
+int mpc85xx_mc_err_probe(struct platform_device *op)
+{
+	struct mem_ctl_info *mci;
+	struct edac_mc_layer layers[2];
+	struct mpc85xx_mc_pdata *pdata;
+	struct resource r;
+	u32 sdram_ctl;
+	int res;
+
+	if (!devres_open_group(&op->dev, mpc85xx_mc_err_probe, GFP_KERNEL))
+		return -ENOMEM;
+
+	layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
+	layers[0].size = 4;
+	layers[0].is_virt_csrow = true;
+	layers[1].type = EDAC_MC_LAYER_CHANNEL;
+	layers[1].size = 1;
+	layers[1].is_virt_csrow = false;
+	mci = edac_mc_alloc(edac_mc_idx, ARRAY_SIZE(layers), layers,
+			    sizeof(*pdata));
+	if (!mci) {
+		devres_release_group(&op->dev, mpc85xx_mc_err_probe);
+		return -ENOMEM;
+	}
+
+	pdata = mci->pvt_info;
+	pdata->name = "mpc85xx_mc_err";
+	pdata->irq = NO_IRQ;
+	mci->pdev = &op->dev;
+	pdata->edac_idx = edac_mc_idx++;
+	dev_set_drvdata(mci->pdev, mci);
+	mci->ctl_name = pdata->name;
+	mci->dev_name = pdata->name;
+
+	res = of_address_to_resource(op->dev.of_node, 0, &r);
+	if (res) {
+		pr_err("%s: Unable to get resource for MC err regs\n",
+		       __func__);
+		goto err;
+	}
+
+	if (!devm_request_mem_region(&op->dev, r.start, resource_size(&r),
+				     pdata->name)) {
+		pr_err("%s: Error while requesting mem region\n",
+		       __func__);
+		res = -EBUSY;
+		goto err;
+	}
+
+	pdata->mc_vbase = devm_ioremap(&op->dev, r.start, resource_size(&r));
+	if (!pdata->mc_vbase) {
+		pr_err("%s: Unable to setup MC err regs\n", __func__);
+		res = -ENOMEM;
+		goto err;
+	}
+
+	sdram_ctl = in_be32(pdata->mc_vbase + MPC85XX_MC_DDR_SDRAM_CFG);
+	if (!(sdram_ctl & DSC_ECC_EN)) {
+		/* no ECC */
+		pr_warn("%s: No ECC DIMMs discovered\n", __func__);
+		res = -ENODEV;
+		goto err;
+	}
+
+	edac_dbg(3, "init mci\n");
+	mci->mtype_cap = MEM_FLAG_RDDR | MEM_FLAG_RDDR2 |
+	    MEM_FLAG_DDR | MEM_FLAG_DDR2;
+	mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_SECDED;
+	mci->edac_cap = EDAC_FLAG_SECDED;
+	mci->mod_name = EDAC_MOD_STR;
+
+	if (edac_op_state == EDAC_OPSTATE_POLL)
+		mci->edac_check = mpc85xx_mc_check;
+
+	mci->ctl_page_to_phys = NULL;
+
+	mci->scrub_mode = SCRUB_SW_SRC;
+
+	mpc85xx_init_csrows(mci);
+
+	/* store the original error disable bits */
+	orig_ddr_err_disable =
+	    in_be32(pdata->mc_vbase + MPC85XX_MC_ERR_DISABLE);
+	out_be32(pdata->mc_vbase + MPC85XX_MC_ERR_DISABLE, 0);
+
+	/* clear all error bits */
+	out_be32(pdata->mc_vbase + MPC85XX_MC_ERR_DETECT, ~0);
+
+	if (edac_mc_add_mc_with_groups(mci, mpc85xx_dev_groups)) {
+		edac_dbg(3, "failed edac_mc_add_mc()\n");
+		goto err;
+	}
+
+	if (edac_op_state == EDAC_OPSTATE_INT) {
+		out_be32(pdata->mc_vbase + MPC85XX_MC_ERR_INT_EN,
+			 DDR_EIE_MBEE | DDR_EIE_SBEE);
+
+		/* store the original error management threshold */
+		orig_ddr_err_sbe = in_be32(pdata->mc_vbase +
+					   MPC85XX_MC_ERR_SBE) & 0xff0000;
+
+		/* set threshold to 1 error per interrupt */
+		out_be32(pdata->mc_vbase + MPC85XX_MC_ERR_SBE, 0x10000);
+
+		/* register interrupts */
+		pdata->irq = irq_of_parse_and_map(op->dev.of_node, 0);
+		res = devm_request_irq(&op->dev, pdata->irq,
+				       mpc85xx_mc_isr,
+				       IRQF_SHARED,
+				       "[EDAC] MC err", mci);
+		if (res < 0) {
+			pr_err("%s: Unable to request irq %d for MPC85xx DRAM ERR\n",
+			       __func__, pdata->irq);
+			irq_dispose_mapping(pdata->irq);
+			res = -ENODEV;
+			goto err2;
+		}
+
+		pr_info(EDAC_MOD_STR " acquired irq %d for MC\n",
+		       pdata->irq);
+	}
+
+	devres_remove_group(&op->dev, mpc85xx_mc_err_probe);
+	edac_dbg(3, "success\n");
+	pr_info(EDAC_MOD_STR " MC err registered\n");
+
+	return 0;
+
+err2:
+	edac_mc_del_mc(&op->dev);
+err:
+	devres_release_group(&op->dev, mpc85xx_mc_err_probe);
+	edac_mc_free(mci);
+	return res;
+}
+
+int mpc85xx_mc_err_remove(struct platform_device *op)
+{
+	struct mem_ctl_info *mci = dev_get_drvdata(&op->dev);
+	struct mpc85xx_mc_pdata *pdata = mci->pvt_info;
+
+	edac_dbg(0, "\n");
+
+	if (edac_op_state == EDAC_OPSTATE_INT) {
+		out_be32(pdata->mc_vbase + MPC85XX_MC_ERR_INT_EN, 0);
+		irq_dispose_mapping(pdata->irq);
+	}
+
+	out_be32(pdata->mc_vbase + MPC85XX_MC_ERR_DISABLE,
+		 orig_ddr_err_disable);
+	out_be32(pdata->mc_vbase + MPC85XX_MC_ERR_SBE, orig_ddr_err_sbe);
+
+	edac_mc_del_mc(&op->dev);
+	edac_mc_free(mci);
+	return 0;
+}