memory: Freescale CoreNet Coherency Fabric error reporting driver

The CoreNet Coherency Fabric is part of the memory subsystem on
some Freescale QorIQ chips. It can report coherency violations (e.g.
due to misusing memory that is mapped noncoherent) as well as
transactions that do not hit any local access window, or which hit a
local access window with an invalid target ID.

Signed-off-by: Scott Wood <[e-mail]>
Reviewed-by: Bharat Bhushan <[e-mail]>

arch/powerpc/configs/corenet32_smp_defconfig

···
 CONFIG_CRYPTO_AES=y
 # CONFIG_CRYPTO_ANSI_CPRNG is not set
 CONFIG_CRYPTO_DEV_FSL_CAAM=y
+CONFIG_FSL_CORENET_CF=y

arch/powerpc/configs/corenet64_smp_defconfig

···
 CONFIG_CRYPTO_SHA512=y
 # CONFIG_CRYPTO_ANSI_CPRNG is not set
 CONFIG_CRYPTO_DEV_FSL_CAAM=y
+CONFIG_FSL_CORENET_CF=y

drivers/memory/Kconfig

···
 	  analysis, especially for IOMMU/SMMU(System Memory Management
 	  Unit) module.
 
+config FSL_CORENET_CF
+	tristate "Freescale CoreNet Error Reporting"
+	depends on FSL_SOC_BOOKE
+	help
+	  Say Y for reporting of errors from the Freescale CoreNet
+	  Coherency Fabric.  Errors reported include accesses to
+	  physical addresses that mapped by no local access window
+	  (LAW) or an invalid LAW, as well as bad cache state that
+	  represents a coherency violation.
+
 config FSL_IFC
 	bool
 	depends on FSL_SOC

drivers/memory/Makefile

···
 endif
 obj-$(CONFIG_TI_AEMIF)		+= ti-aemif.o
 obj-$(CONFIG_TI_EMIF)		+= emif.o
+obj-$(CONFIG_FSL_CORENET_CF)	+= fsl-corenet-cf.o
 obj-$(CONFIG_FSL_IFC)		+= fsl_ifc.o
 obj-$(CONFIG_MVEBU_DEVBUS)	+= mvebu-devbus.o
 obj-$(CONFIG_TEGRA20_MC)	+= tegra20-mc.o

drivers/memory/fsl-corenet-cf.c

···
+/*
+ * CoreNet Coherency Fabric error reporting
+ *
+ * Copyright 2014 Freescale Semiconductor 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.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+
+enum ccf_version {
+	CCF1,
+	CCF2,
+};
+
+struct ccf_info {
+	enum ccf_version version;
+	int err_reg_offs;
+};
+
+static const struct ccf_info ccf1_info = {
+	.version = CCF1,
+	.err_reg_offs = 0xa00,
+};
+
+static const struct ccf_info ccf2_info = {
+	.version = CCF2,
+	.err_reg_offs = 0xe40,
+};
+
+static const struct of_device_id ccf_matches[] = {
+	{
+		.compatible = "fsl,corenet1-cf",
+		.data = &ccf1_info,
+	},
+	{
+		.compatible = "fsl,corenet2-cf",
+		.data = &ccf2_info,
+	},
+	{}
+};
+
+struct ccf_err_regs {
+	u32 errdet;		/* 0x00 Error Detect Register */
+	/* 0x04 Error Enable (ccf1)/Disable (ccf2) Register */
+	u32 errdis;
+	/* 0x08 Error Interrupt Enable Register (ccf2 only) */
+	u32 errinten;
+	u32 cecar;		/* 0x0c Error Capture Attribute Register */
+	u32 cecaddrh;		/* 0x10 Error Capture Address High */
+	u32 cecaddrl;		/* 0x14 Error Capture Address Low */
+	u32 cecar2;		/* 0x18 Error Capture Attribute Register 2 */
+};
+
+/* LAE/CV also valid for errdis and errinten */
+#define ERRDET_LAE		(1 << 0)  /* Local Access Error */
+#define ERRDET_CV		(1 << 1)  /* Coherency Violation */
+#define ERRDET_CTYPE_SHIFT	26	  /* Capture Type (ccf2 only) */
+#define ERRDET_CTYPE_MASK	(0x1f << ERRDET_CTYPE_SHIFT)
+#define ERRDET_CAP		(1 << 31) /* Capture Valid (ccf2 only) */
+
+#define CECAR_VAL		(1 << 0)  /* Valid (ccf1 only) */
+#define CECAR_UVT		(1 << 15) /* Unavailable target ID (ccf1) */
+#define CECAR_SRCID_SHIFT_CCF1	24
+#define CECAR_SRCID_MASK_CCF1	(0xff << CECAR_SRCID_SHIFT_CCF1)
+#define CECAR_SRCID_SHIFT_CCF2	18
+#define CECAR_SRCID_MASK_CCF2	(0xff << CECAR_SRCID_SHIFT_CCF2)
+
+#define CECADDRH_ADDRH		0xff
+
+struct ccf_private {
+	const struct ccf_info *info;
+	struct device *dev;
+	void __iomem *regs;
+	struct ccf_err_regs __iomem *err_regs;
+};
+
+static irqreturn_t ccf_irq(int irq, void *dev_id)
+{
+	struct ccf_private *ccf = dev_id;
+	static DEFINE_RATELIMIT_STATE(ratelimit, DEFAULT_RATELIMIT_INTERVAL,
+				      DEFAULT_RATELIMIT_BURST);
+	u32 errdet, cecar, cecar2;
+	u64 addr;
+	u32 src_id;
+	bool uvt = false;
+	bool cap_valid = false;
+
+	errdet = ioread32be(&ccf->err_regs->errdet);
+	cecar = ioread32be(&ccf->err_regs->cecar);
+	cecar2 = ioread32be(&ccf->err_regs->cecar2);
+	addr = ioread32be(&ccf->err_regs->cecaddrl);
+	addr |= ((u64)(ioread32be(&ccf->err_regs->cecaddrh) &
+		       CECADDRH_ADDRH)) << 32;
+
+	if (!__ratelimit(&ratelimit))
+		goto out;
+
+	switch (ccf->info->version) {
+	case CCF1:
+		if (cecar & CECAR_VAL) {
+			if (cecar & CECAR_UVT)
+				uvt = true;
+
+			src_id = (cecar & CECAR_SRCID_MASK_CCF1) >>
+				 CECAR_SRCID_SHIFT_CCF1;
+			cap_valid = true;
+		}
+
+		break;
+	case CCF2:
+		if (errdet & ERRDET_CAP) {
+			src_id = (cecar & CECAR_SRCID_MASK_CCF2) >>
+				 CECAR_SRCID_SHIFT_CCF2;
+			cap_valid = true;
+		}
+
+		break;
+	}
+
+	dev_crit(ccf->dev, "errdet 0x%08x cecar 0x%08x cecar2 0x%08x\n",
+		 errdet, cecar, cecar2);
+
+	if (errdet & ERRDET_LAE) {
+		if (uvt)
+			dev_crit(ccf->dev, "LAW Unavailable Target ID\n");
+		else
+			dev_crit(ccf->dev, "Local Access Window Error\n");
+	}
+
+	if (errdet & ERRDET_CV)
+		dev_crit(ccf->dev, "Coherency Violation\n");
+
+	if (cap_valid) {
+		dev_crit(ccf->dev, "address 0x%09llx, src id 0x%x\n",
+			 addr, src_id);
+	}
+
+out:
+	iowrite32be(errdet, &ccf->err_regs->errdet);
+	return errdet ? IRQ_HANDLED : IRQ_NONE;
+}
+
+static int ccf_probe(struct platform_device *pdev)
+{
+	struct ccf_private *ccf;
+	struct resource *r;
+	const struct of_device_id *match;
+	int ret, irq;
+
+	match = of_match_device(ccf_matches, &pdev->dev);
+	if (WARN_ON(!match))
+		return -ENODEV;
+
+	ccf = devm_kzalloc(&pdev->dev, sizeof(*ccf), GFP_KERNEL);
+	if (!ccf)
+		return -ENOMEM;
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!r) {
+		dev_err(&pdev->dev, "%s: no mem resource\n", __func__);
+		return -ENXIO;
+	}
+
+	ccf->regs = devm_ioremap_resource(&pdev->dev, r);
+	if (IS_ERR(ccf->regs)) {
+		dev_err(&pdev->dev, "%s: can't map mem resource\n", __func__);
+		return PTR_ERR(ccf->regs);
+	}
+
+	ccf->dev = &pdev->dev;
+	ccf->info = match->data;
+	ccf->err_regs = ccf->regs + ccf->info->err_reg_offs;
+
+	dev_set_drvdata(&pdev->dev, ccf);
+
+	irq = platform_get_irq(pdev, 0);
+	if (!irq) {
+		dev_err(&pdev->dev, "%s: no irq\n", __func__);
+		return -ENXIO;
+	}
+
+	ret = devm_request_irq(&pdev->dev, irq, ccf_irq, 0, pdev->name, ccf);
+	if (ret) {
+		dev_err(&pdev->dev, "%s: can't request irq\n", __func__);
+		return ret;
+	}
+
+	switch (ccf->info->version) {
+	case CCF1:
+		/* On CCF1 this register enables rather than disables. */
+		iowrite32be(ERRDET_LAE | ERRDET_CV, &ccf->err_regs->errdis);
+		break;
+
+	case CCF2:
+		iowrite32be(0, &ccf->err_regs->errdis);
+		iowrite32be(ERRDET_LAE | ERRDET_CV, &ccf->err_regs->errinten);
+		break;
+	}
+
+	return 0;
+}
+
+static int ccf_remove(struct platform_device *pdev)
+{
+	struct ccf_private *ccf = dev_get_drvdata(&pdev->dev);
+
+	switch (ccf->info->version) {
+	case CCF1:
+		iowrite32be(0, &ccf->err_regs->errdis);
+		break;
+
+	case CCF2:
+		/*
+		 * We clear errdis on ccf1 because that's the only way to
+		 * disable interrupts, but on ccf2 there's no need to disable
+		 * detection.
+		 */
+		iowrite32be(0, &ccf->err_regs->errinten);
+		break;
+	}
+
+	return 0;
+}
+
+static struct platform_driver ccf_driver = {
+	.driver = {
+		.name = KBUILD_MODNAME,
+		.owner = THIS_MODULE,
+		.of_match_table = ccf_matches,
+	},
+	.probe = ccf_probe,
+	.remove = ccf_remove,
+};
+
+module_platform_driver(ccf_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Freescale Semiconductor");
+MODULE_DESCRIPTION("Freescale CoreNet Coherency Fabric error reporting");