MIPS: Cavium: Add EDAC support.

Drivers for EDAC on Cavium.  Supported subsystems are:

 o CPU primary caches.  These are parity protected only, so only error
   reporting.
 o Second level cache - ECC protected, provides SECDED.
 o Memory: ECC / SECDEC if used with suitable DRAM modules.  The driver will
   will only initialize if ECC is enabled on a system so is safe to run on
   non-ECC memory.
 o PCI: Parity error reporting

Since it is very hard to test this sort of code the implementation is very
conservative and uses polling where possible for now.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Reviewed-by: Borislav Petkov <borislav.petkov@amd.com>
diff --git a/drivers/edac/octeon_edac-lmc.c b/drivers/edac/octeon_edac-lmc.c
new file mode 100644
index 0000000..e0c1e44
--- /dev/null
+++ b/drivers/edac/octeon_edac-lmc.c
@@ -0,0 +1,150 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2009 Wind River Systems,
+ *   written by Ralf Baechle <ralf@linux-mips.org>
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/edac.h>
+
+#include <asm/octeon/cvmx.h>
+
+#include "edac_core.h"
+#include "edac_module.h"
+#include "octeon_edac-lmc.h"
+
+#define EDAC_MOD_STR "octeon"
+
+static struct mem_ctl_info *mc_cavium;
+static void *lmc_base;
+
+static void co_lmc_poll(struct mem_ctl_info *mci)
+{
+	union lmc_mem_cfg0 cfg0;
+	union lmc_fadr fadr;
+	char msg[64];
+
+	fadr.u64 = readq(lmc_base + LMC_FADR);
+	cfg0.u64 = readq(lmc_base + LMC_MEM_CFG0);
+	snprintf(msg, sizeof(msg), "DIMM %d rank %d bank %d row %d col %d",
+		fadr.fdimm, fadr.fbunk, fadr.fbank, fadr.frow, fadr.fcol);
+
+	if (cfg0.sec_err) {
+		edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, 1, 0, 0, 0, -1, -1, -1,
+				     msg, "");
+
+		cfg0.intr_sec_ena = -1;		/* Done, re-arm */
+	}
+
+	if (cfg0.ded_err) {
+		edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci, 1, 0, 0, 0, -1, -1, -1,
+				     msg, "");
+		cfg0.intr_ded_ena = -1;		/* Done, re-arm */
+	}
+
+	writeq(cfg0.u64, lmc_base + LMC_MEM_CFG0);
+}
+
+static int __devinit co_lmc_probe(struct platform_device *pdev)
+{
+	struct mem_ctl_info *mci;
+	union lmc_mem_cfg0 cfg0;
+	int res = 0;
+
+	mci = edac_mc_alloc(0, 0, 0, 0);
+	if (!mci)
+		return -ENOMEM;
+
+	mci->pdev = &pdev->dev;
+	platform_set_drvdata(pdev, mci);
+	mci->dev_name = dev_name(&pdev->dev);
+
+	mci->mod_name = "octeon-lmc";
+	mci->ctl_name = "co_lmc_err";
+	mci->edac_check = co_lmc_poll;
+
+	if (edac_mc_add_mc(mci) > 0) {
+		pr_err("%s: edac_mc_add_mc() failed\n", __func__);
+		goto err;
+	}
+
+	cfg0.u64 = readq(lmc_base + LMC_MEM_CFG0);	/* We poll */
+	cfg0.intr_ded_ena = 0;
+	cfg0.intr_sec_ena = 0;
+	writeq(cfg0.u64, lmc_base + LMC_MEM_CFG0);
+
+	mc_cavium = mci;
+
+	return 0;
+
+err:
+	edac_mc_free(mci);
+
+	return res;
+}
+
+static int co_lmc_remove(struct platform_device *pdev)
+{
+	struct mem_ctl_info *mci = platform_get_drvdata(pdev);
+
+	mc_cavium = NULL;
+	edac_mc_del_mc(&pdev->dev);
+	edac_mc_free(mci);
+
+	return 0;
+}
+
+static struct platform_driver co_lmc_driver = {
+	.probe = co_lmc_probe,
+	.remove = co_lmc_remove,
+	.driver = {
+		   .name = "co_lmc_edac",
+	}
+};
+
+static int __init co_edac_init(void)
+{
+	union lmc_mem_cfg0 cfg0;
+	int ret;
+
+	lmc_base = ioremap_nocache(LMC_BASE, LMC_SIZE);
+	if (!lmc_base)
+		return -ENOMEM;
+
+	cfg0.u64 = readq(lmc_base + LMC_MEM_CFG0);
+	if (!cfg0.ecc_ena) {
+		pr_info(EDAC_MOD_STR " LMC EDAC: ECC disabled, good bye\n");
+		ret = -ENODEV;
+		goto out;
+	}
+
+	ret = platform_driver_register(&co_lmc_driver);
+	if (ret) {
+		pr_warning(EDAC_MOD_STR " LMC EDAC failed to register\n");
+		goto out;
+	}
+
+	return ret;
+
+out:
+	iounmap(lmc_base);
+
+	return ret;
+}
+
+static void __exit co_edac_exit(void)
+{
+	platform_driver_unregister(&co_lmc_driver);
+	iounmap(lmc_base);
+}
+
+module_init(co_edac_init);
+module_exit(co_edac_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Ralf Baechle <ralf@linux-mips.org>");