drivers/memory/tegra/mc.c - kernel/msm-4.9 - Gitiles

 /*
  * Copyright (C) 2014 NVIDIA CORPORATION.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */

 #include <linux/clk.h>
 #include <linux/interrupt.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/sort.h>

 #include <soc/tegra/fuse.h>

 #include "mc.h"

 #define MC_INTSTATUS 0x000
 #define  MC_INT_DECERR_MTS (1 << 16)
 #define  MC_INT_SECERR_SEC (1 << 13)
 #define  MC_INT_DECERR_VPR (1 << 12)
 #define  MC_INT_INVALID_APB_ASID_UPDATE (1 << 11)
 #define  MC_INT_INVALID_SMMU_PAGE (1 << 10)
 #define  MC_INT_ARBITRATION_EMEM (1 << 9)
 #define  MC_INT_SECURITY_VIOLATION (1 << 8)
 #define  MC_INT_DECERR_EMEM (1 << 6)

 #define MC_INTMASK 0x004

 #define MC_ERR_STATUS 0x08
 #define  MC_ERR_STATUS_TYPE_SHIFT 28
 #define  MC_ERR_STATUS_TYPE_INVALID_SMMU_PAGE (6 << MC_ERR_STATUS_TYPE_SHIFT)
 #define  MC_ERR_STATUS_TYPE_MASK (0x7 << MC_ERR_STATUS_TYPE_SHIFT)
 #define  MC_ERR_STATUS_READABLE (1 << 27)
 #define  MC_ERR_STATUS_WRITABLE (1 << 26)
 #define  MC_ERR_STATUS_NONSECURE (1 << 25)
 #define  MC_ERR_STATUS_ADR_HI_SHIFT 20
 #define  MC_ERR_STATUS_ADR_HI_MASK 0x3
 #define  MC_ERR_STATUS_SECURITY (1 << 17)
 #define  MC_ERR_STATUS_RW (1 << 16)

 #define MC_ERR_ADR 0x0c

 #define MC_EMEM_ARB_CFG 0x90
 #define  MC_EMEM_ARB_CFG_CYCLES_PER_UPDATE(x)	(((x) & 0x1ff) << 0)
 #define  MC_EMEM_ARB_CFG_CYCLES_PER_UPDATE_MASK	0x1ff
 #define MC_EMEM_ARB_MISC0 0xd8

 #define MC_EMEM_ADR_CFG 0x54
 #define MC_EMEM_ADR_CFG_EMEM_NUMDEV BIT(0)

 static const struct of_device_id tegra_mc_of_match[] = {
 #ifdef CONFIG_ARCH_TEGRA_3x_SOC
 	{ .compatible = "nvidia,tegra30-mc", .data = &tegra30_mc_soc },
 #endif
 #ifdef CONFIG_ARCH_TEGRA_114_SOC
 	{ .compatible = "nvidia,tegra114-mc", .data = &tegra114_mc_soc },
 #endif
 #ifdef CONFIG_ARCH_TEGRA_124_SOC
 	{ .compatible = "nvidia,tegra124-mc", .data = &tegra124_mc_soc },
 #endif
 #ifdef CONFIG_ARCH_TEGRA_132_SOC
 	{ .compatible = "nvidia,tegra132-mc", .data = &tegra132_mc_soc },
 #endif
 #ifdef CONFIG_ARCH_TEGRA_210_SOC
 	{ .compatible = "nvidia,tegra210-mc", .data = &tegra210_mc_soc },
 #endif
 	{ }
 };
 MODULE_DEVICE_TABLE(of, tegra_mc_of_match);

 static int tegra_mc_setup_latency_allowance(struct tegra_mc *mc)
 {
 	unsigned long long tick;
 	unsigned int i;
 	u32 value;

 	/* compute the number of MC clock cycles per tick */
 	tick = mc->tick * clk_get_rate(mc->clk);
 	do_div(tick, NSEC_PER_SEC);

 	value = readl(mc->regs + MC_EMEM_ARB_CFG);
 	value &= ~MC_EMEM_ARB_CFG_CYCLES_PER_UPDATE_MASK;
 	value |= MC_EMEM_ARB_CFG_CYCLES_PER_UPDATE(tick);
 	writel(value, mc->regs + MC_EMEM_ARB_CFG);

 	/* write latency allowance defaults */
 	for (i = 0; i < mc->soc->num_clients; i++) {
 		const struct tegra_mc_la *la = &mc->soc->clients[i].la;
 		u32 value;

 		value = readl(mc->regs + la->reg);
 		value &= ~(la->mask << la->shift);
 		value |= (la->def & la->mask) << la->shift;
 		writel(value, mc->regs + la->reg);
 	}

 	return 0;
 }

 void tegra_mc_write_emem_configuration(struct tegra_mc *mc, unsigned long rate)
 {
 	unsigned int i;
 	struct tegra_mc_timing *timing = NULL;

 	for (i = 0; i < mc->num_timings; i++) {
 		if (mc->timings[i].rate == rate) {
 			timing = &mc->timings[i];
 			break;
 		}
 	}

 	if (!timing) {
 		dev_err(mc->dev, "no memory timing registered for rate %lu\n",
 			rate);
 		return;
 	}

 	for (i = 0; i < mc->soc->num_emem_regs; ++i)
 		mc_writel(mc, timing->emem_data[i], mc->soc->emem_regs[i]);
 }

 unsigned int tegra_mc_get_emem_device_count(struct tegra_mc *mc)
 {
 	u8 dram_count;

 	dram_count = mc_readl(mc, MC_EMEM_ADR_CFG);
 	dram_count &= MC_EMEM_ADR_CFG_EMEM_NUMDEV;
 	dram_count++;

 	return dram_count;
 }

 static int load_one_timing(struct tegra_mc *mc,
 			   struct tegra_mc_timing *timing,
 			   struct device_node *node)
 {
 	int err;
 	u32 tmp;

 	err = of_property_read_u32(node, "clock-frequency", &tmp);
 	if (err) {
 		dev_err(mc->dev,
 			"timing %s: failed to read rate\n", node->name);
 		return err;
 	}

 	timing->rate = tmp;
 	timing->emem_data = devm_kcalloc(mc->dev, mc->soc->num_emem_regs,
 					 sizeof(u32), GFP_KERNEL);
 	if (!timing->emem_data)
 		return -ENOMEM;

 	err = of_property_read_u32_array(node, "nvidia,emem-configuration",
 					 timing->emem_data,
 					 mc->soc->num_emem_regs);
 	if (err) {
 		dev_err(mc->dev,
 			"timing %s: failed to read EMEM configuration\n",
 			node->name);
 		return err;
 	}

 	return 0;
 }

 static int load_timings(struct tegra_mc *mc, struct device_node *node)
 {
 	struct device_node *child;
 	struct tegra_mc_timing *timing;
 	int child_count = of_get_child_count(node);
 	int i = 0, err;

 	mc->timings = devm_kcalloc(mc->dev, child_count, sizeof(*timing),
 				   GFP_KERNEL);
 	if (!mc->timings)
 		return -ENOMEM;

 	mc->num_timings = child_count;

 	for_each_child_of_node(node, child) {
 		timing = &mc->timings[i++];

 		err = load_one_timing(mc, timing, child);
 		if (err)
 			return err;
 	}

 	return 0;
 }

 static int tegra_mc_setup_timings(struct tegra_mc *mc)
 {
 	struct device_node *node;
 	u32 ram_code, node_ram_code;
 	int err;

 	ram_code = tegra_read_ram_code();

 	mc->num_timings = 0;

 	for_each_child_of_node(mc->dev->of_node, node) {
 		err = of_property_read_u32(node, "nvidia,ram-code",
 					   &node_ram_code);
 		if (err || (node_ram_code != ram_code)) {
 			of_node_put(node);
 			continue;
 		}

 		err = load_timings(mc, node);
 		if (err)
 			return err;
 		of_node_put(node);
 		break;
 	}

 	if (mc->num_timings == 0)
 		dev_warn(mc->dev,
 			 "no memory timings for RAM code %u registered\n",
 			 ram_code);

 	return 0;
 }

 static const char *const status_names[32] = {
 	[ 1] = "External interrupt",
 	[ 6] = "EMEM address decode error",
 	[ 8] = "Security violation",
 	[ 9] = "EMEM arbitration error",
 	[10] = "Page fault",
 	[11] = "Invalid APB ASID update",
 	[12] = "VPR violation",
 	[13] = "Secure carveout violation",
 	[16] = "MTS carveout violation",
 };

 static const char *const error_names[8] = {
 	[2] = "EMEM decode error",
 	[3] = "TrustZone violation",
 	[4] = "Carveout violation",
 	[6] = "SMMU translation error",
 };

 static irqreturn_t tegra_mc_irq(int irq, void *data)
 {
 	struct tegra_mc *mc = data;
 	unsigned long status, mask;
 	unsigned int bit;

 	/* mask all interrupts to avoid flooding */
 	status = mc_readl(mc, MC_INTSTATUS);
 	mask = mc_readl(mc, MC_INTMASK);

 	for_each_set_bit(bit, &status, 32) {
 		const char *error = status_names[bit] ?: "unknown";
 		const char *client = "unknown", *desc;
 		const char *direction, *secure;
 		phys_addr_t addr = 0;
 		unsigned int i;
 		char perm[7];
 		u8 id, type;
 		u32 value;

 		value = mc_readl(mc, MC_ERR_STATUS);

 #ifdef CONFIG_PHYS_ADDR_T_64BIT
 		if (mc->soc->num_address_bits > 32) {
 			addr = ((value >> MC_ERR_STATUS_ADR_HI_SHIFT) &
 				MC_ERR_STATUS_ADR_HI_MASK);
 			addr <<= 32;
 		}
 #endif

 		if (value & MC_ERR_STATUS_RW)
 			direction = "write";
 		else
 			direction = "read";

 		if (value & MC_ERR_STATUS_SECURITY)
 			secure = "secure ";
 		else
 			secure = "";

 		id = value & mc->soc->client_id_mask;

 		for (i = 0; i < mc->soc->num_clients; i++) {
 			if (mc->soc->clients[i].id == id) {
 				client = mc->soc->clients[i].name;
 				break;
 			}
 		}

 		type = (value & MC_ERR_STATUS_TYPE_MASK) >>
 		       MC_ERR_STATUS_TYPE_SHIFT;
 		desc = error_names[type];

 		switch (value & MC_ERR_STATUS_TYPE_MASK) {
 		case MC_ERR_STATUS_TYPE_INVALID_SMMU_PAGE:
 			perm[0] = ' ';
 			perm[1] = '[';

 			if (value & MC_ERR_STATUS_READABLE)
 				perm[2] = 'R';
 			else
 				perm[2] = '-';

 			if (value & MC_ERR_STATUS_WRITABLE)
 				perm[3] = 'W';
 			else
 				perm[3] = '-';

 			if (value & MC_ERR_STATUS_NONSECURE)
 				perm[4] = '-';
 			else
 				perm[4] = 'S';

 			perm[5] = ']';
 			perm[6] = '\0';
 			break;

 		default:
 			perm[0] = '\0';
 			break;
 		}

 		value = mc_readl(mc, MC_ERR_ADR);
 		addr |= value;

 		dev_err_ratelimited(mc->dev, "%s: %s%s @%pa: %s (%s%s)\n",
 				    client, secure, direction, &addr, error,
 				    desc, perm);
 	}

 	/* clear interrupts */
 	mc_writel(mc, status, MC_INTSTATUS);

 	return IRQ_HANDLED;
 }

 static int tegra_mc_probe(struct platform_device *pdev)
 {
 	const struct of_device_id *match;
 	struct resource *res;
 	struct tegra_mc *mc;
 	u32 value;
 	int err;

 	match = of_match_node(tegra_mc_of_match, pdev->dev.of_node);
 	if (!match)
 		return -ENODEV;

 	mc = devm_kzalloc(&pdev->dev, sizeof(*mc), GFP_KERNEL);
 	if (!mc)
 		return -ENOMEM;

 	platform_set_drvdata(pdev, mc);
 	mc->soc = match->data;
 	mc->dev = &pdev->dev;

 	/* length of MC tick in nanoseconds */
 	mc->tick = 30;

 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	mc->regs = devm_ioremap_resource(&pdev->dev, res);
 	if (IS_ERR(mc->regs))
 		return PTR_ERR(mc->regs);

 	mc->clk = devm_clk_get(&pdev->dev, "mc");
 	if (IS_ERR(mc->clk)) {
 		dev_err(&pdev->dev, "failed to get MC clock: %ld\n",
 			PTR_ERR(mc->clk));
 		return PTR_ERR(mc->clk);
 	}

 	err = tegra_mc_setup_latency_allowance(mc);
 	if (err < 0) {
 		dev_err(&pdev->dev, "failed to setup latency allowance: %d\n",
 			err);
 		return err;
 	}

 	err = tegra_mc_setup_timings(mc);
 	if (err < 0) {
 		dev_err(&pdev->dev, "failed to setup timings: %d\n", err);
 		return err;
 	}

 	if (IS_ENABLED(CONFIG_TEGRA_IOMMU_SMMU)) {
 		mc->smmu = tegra_smmu_probe(&pdev->dev, mc->soc->smmu, mc);
 		if (IS_ERR(mc->smmu)) {
 			dev_err(&pdev->dev, "failed to probe SMMU: %ld\n",
 				PTR_ERR(mc->smmu));
 			return PTR_ERR(mc->smmu);
 		}
 	}

 	mc->irq = platform_get_irq(pdev, 0);
 	if (mc->irq < 0) {
 		dev_err(&pdev->dev, "interrupt not specified\n");
 		return mc->irq;
 	}

 	err = devm_request_irq(&pdev->dev, mc->irq, tegra_mc_irq, IRQF_SHARED,
 			       dev_name(&pdev->dev), mc);
 	if (err < 0) {
 		dev_err(&pdev->dev, "failed to request IRQ#%u: %d\n", mc->irq,
 			err);
 		return err;
 	}

 	WARN(!mc->soc->client_id_mask, "Missing client ID mask for this SoC\n");

 	value = MC_INT_DECERR_MTS | MC_INT_SECERR_SEC | MC_INT_DECERR_VPR |
 		MC_INT_INVALID_APB_ASID_UPDATE | MC_INT_INVALID_SMMU_PAGE |
 		MC_INT_SECURITY_VIOLATION | MC_INT_DECERR_EMEM;

 	mc_writel(mc, value, MC_INTMASK);

 	return 0;
 }

 static struct platform_driver tegra_mc_driver = {
 	.driver = {
 		.name = "tegra-mc",
 		.of_match_table = tegra_mc_of_match,
 		.suppress_bind_attrs = true,
 	},
 	.prevent_deferred_probe = true,
 	.probe = tegra_mc_probe,
 };

 static int tegra_mc_init(void)
 {
 	return platform_driver_register(&tegra_mc_driver);
 }
 arch_initcall(tegra_mc_init);

 MODULE_AUTHOR("Thierry Reding <treding@nvidia.com>");
 MODULE_DESCRIPTION("NVIDIA Tegra Memory Controller driver");
 MODULE_LICENSE("GPL v2");
	/*
	* Copyright (C) 2014 NVIDIA CORPORATION. All rights reserved.
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*/

	#include <linux/clk.h>
	#include <linux/interrupt.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/of.h>
	#include <linux/platform_device.h>
	#include <linux/slab.h>
	#include <linux/sort.h>

	#include <soc/tegra/fuse.h>

	#include "mc.h"

	#define MC_INTSTATUS 0x000
	#define MC_INT_DECERR_MTS (1 << 16)
	#define MC_INT_SECERR_SEC (1 << 13)
	#define MC_INT_DECERR_VPR (1 << 12)
	#define MC_INT_INVALID_APB_ASID_UPDATE (1 << 11)
	#define MC_INT_INVALID_SMMU_PAGE (1 << 10)
	#define MC_INT_ARBITRATION_EMEM (1 << 9)
	#define MC_INT_SECURITY_VIOLATION (1 << 8)
	#define MC_INT_DECERR_EMEM (1 << 6)

	#define MC_INTMASK 0x004

	#define MC_ERR_STATUS 0x08
	#define MC_ERR_STATUS_TYPE_SHIFT 28
	#define MC_ERR_STATUS_TYPE_INVALID_SMMU_PAGE (6 << MC_ERR_STATUS_TYPE_SHIFT)
	#define MC_ERR_STATUS_TYPE_MASK (0x7 << MC_ERR_STATUS_TYPE_SHIFT)
	#define MC_ERR_STATUS_READABLE (1 << 27)
	#define MC_ERR_STATUS_WRITABLE (1 << 26)
	#define MC_ERR_STATUS_NONSECURE (1 << 25)
	#define MC_ERR_STATUS_ADR_HI_SHIFT 20
	#define MC_ERR_STATUS_ADR_HI_MASK 0x3
	#define MC_ERR_STATUS_SECURITY (1 << 17)
	#define MC_ERR_STATUS_RW (1 << 16)

	#define MC_ERR_ADR 0x0c

	#define MC_EMEM_ARB_CFG 0x90
	#define MC_EMEM_ARB_CFG_CYCLES_PER_UPDATE(x) (((x) & 0x1ff) << 0)
	#define MC_EMEM_ARB_CFG_CYCLES_PER_UPDATE_MASK 0x1ff
	#define MC_EMEM_ARB_MISC0 0xd8

	#define MC_EMEM_ADR_CFG 0x54
	#define MC_EMEM_ADR_CFG_EMEM_NUMDEV BIT(0)

	static const struct of_device_id tegra_mc_of_match[] = {
	#ifdef CONFIG_ARCH_TEGRA_3x_SOC
	{ .compatible = "nvidia,tegra30-mc", .data = &tegra30_mc_soc },
	#endif
	#ifdef CONFIG_ARCH_TEGRA_114_SOC
	{ .compatible = "nvidia,tegra114-mc", .data = &tegra114_mc_soc },
	#endif
	#ifdef CONFIG_ARCH_TEGRA_124_SOC
	{ .compatible = "nvidia,tegra124-mc", .data = &tegra124_mc_soc },
	#endif
	#ifdef CONFIG_ARCH_TEGRA_132_SOC
	{ .compatible = "nvidia,tegra132-mc", .data = &tegra132_mc_soc },
	#endif
	#ifdef CONFIG_ARCH_TEGRA_210_SOC
	{ .compatible = "nvidia,tegra210-mc", .data = &tegra210_mc_soc },
	#endif
	{ }
	};
	MODULE_DEVICE_TABLE(of, tegra_mc_of_match);

	static int tegra_mc_setup_latency_allowance(struct tegra_mc *mc)
	{
	unsigned long long tick;
	unsigned int i;
	u32 value;

	/* compute the number of MC clock cycles per tick */
	tick = mc->tick * clk_get_rate(mc->clk);
	do_div(tick, NSEC_PER_SEC);

	value = readl(mc->regs + MC_EMEM_ARB_CFG);
	value &= ~MC_EMEM_ARB_CFG_CYCLES_PER_UPDATE_MASK;
	value \|= MC_EMEM_ARB_CFG_CYCLES_PER_UPDATE(tick);
	writel(value, mc->regs + MC_EMEM_ARB_CFG);

	/* write latency allowance defaults */
	for (i = 0; i < mc->soc->num_clients; i++) {
	const struct tegra_mc_la *la = &mc->soc->clients[i].la;
	u32 value;

	value = readl(mc->regs + la->reg);
	value &= ~(la->mask << la->shift);
	value \|= (la->def & la->mask) << la->shift;
	writel(value, mc->regs + la->reg);
	}

	return 0;
	}

	void tegra_mc_write_emem_configuration(struct tegra_mc *mc, unsigned long rate)
	{
	unsigned int i;
	struct tegra_mc_timing *timing = NULL;

	for (i = 0; i < mc->num_timings; i++) {
	if (mc->timings[i].rate == rate) {
	timing = &mc->timings[i];
	break;
	}
	}

	if (!timing) {
	dev_err(mc->dev, "no memory timing registered for rate %lu\n",
	rate);
	return;
	}

	for (i = 0; i < mc->soc->num_emem_regs; ++i)
	mc_writel(mc, timing->emem_data[i], mc->soc->emem_regs[i]);
	}

	unsigned int tegra_mc_get_emem_device_count(struct tegra_mc *mc)
	{
	u8 dram_count;

	dram_count = mc_readl(mc, MC_EMEM_ADR_CFG);
	dram_count &= MC_EMEM_ADR_CFG_EMEM_NUMDEV;
	dram_count++;

	return dram_count;
	}

	static int load_one_timing(struct tegra_mc *mc,
	struct tegra_mc_timing *timing,
	struct device_node *node)
	{
	int err;
	u32 tmp;

	err = of_property_read_u32(node, "clock-frequency", &tmp);
	if (err) {
	dev_err(mc->dev,
	"timing %s: failed to read rate\n", node->name);
	return err;
	}

	timing->rate = tmp;
	timing->emem_data = devm_kcalloc(mc->dev, mc->soc->num_emem_regs,
	sizeof(u32), GFP_KERNEL);
	if (!timing->emem_data)
	return -ENOMEM;

	err = of_property_read_u32_array(node, "nvidia,emem-configuration",
	timing->emem_data,
	mc->soc->num_emem_regs);
	if (err) {
	dev_err(mc->dev,
	"timing %s: failed to read EMEM configuration\n",
	node->name);
	return err;
	}

	return 0;
	}

	static int load_timings(struct tegra_mc mc, struct device_node node)
	{
	struct device_node *child;
	struct tegra_mc_timing *timing;
	int child_count = of_get_child_count(node);
	int i = 0, err;

	mc->timings = devm_kcalloc(mc->dev, child_count, sizeof(*timing),
	GFP_KERNEL);
	if (!mc->timings)
	return -ENOMEM;

	mc->num_timings = child_count;

	for_each_child_of_node(node, child) {
	timing = &mc->timings[i++];

	err = load_one_timing(mc, timing, child);
	if (err)
	return err;
	}

	return 0;
	}

	static int tegra_mc_setup_timings(struct tegra_mc *mc)
	{
	struct device_node *node;
	u32 ram_code, node_ram_code;
	int err;

	ram_code = tegra_read_ram_code();

	mc->num_timings = 0;

	for_each_child_of_node(mc->dev->of_node, node) {
	err = of_property_read_u32(node, "nvidia,ram-code",
	&node_ram_code);
	if (err \|\| (node_ram_code != ram_code)) {
	of_node_put(node);
	continue;
	}

	err = load_timings(mc, node);
	if (err)
	return err;
	of_node_put(node);
	break;
	}

	if (mc->num_timings == 0)
	dev_warn(mc->dev,
	"no memory timings for RAM code %u registered\n",
	ram_code);

	return 0;
	}

	static const char *const status_names[32] = {
	[ 1] = "External interrupt",
	[ 6] = "EMEM address decode error",
	[ 8] = "Security violation",
	[ 9] = "EMEM arbitration error",
	[10] = "Page fault",
	[11] = "Invalid APB ASID update",
	[12] = "VPR violation",
	[13] = "Secure carveout violation",
	[16] = "MTS carveout violation",
	};

	static const char *const error_names[8] = {
	[2] = "EMEM decode error",
	[3] = "TrustZone violation",
	[4] = "Carveout violation",
	[6] = "SMMU translation error",
	};

	static irqreturn_t tegra_mc_irq(int irq, void *data)
	{
	struct tegra_mc *mc = data;
	unsigned long status, mask;
	unsigned int bit;

	/* mask all interrupts to avoid flooding */
	status = mc_readl(mc, MC_INTSTATUS);
	mask = mc_readl(mc, MC_INTMASK);

	for_each_set_bit(bit, &status, 32) {
	const char *error = status_names[bit] ?: "unknown";
	const char client = "unknown", desc;
	const char direction, secure;
	phys_addr_t addr = 0;
	unsigned int i;
	char perm[7];
	u8 id, type;
	u32 value;

	value = mc_readl(mc, MC_ERR_STATUS);

	#ifdef CONFIG_PHYS_ADDR_T_64BIT
	if (mc->soc->num_address_bits > 32) {
	addr = ((value >> MC_ERR_STATUS_ADR_HI_SHIFT) &
	MC_ERR_STATUS_ADR_HI_MASK);
	addr <<= 32;
	}
	#endif

	if (value & MC_ERR_STATUS_RW)
	direction = "write";
	else
	direction = "read";

	if (value & MC_ERR_STATUS_SECURITY)
	secure = "secure ";
	else
	secure = "";

	id = value & mc->soc->client_id_mask;

	for (i = 0; i < mc->soc->num_clients; i++) {
	if (mc->soc->clients[i].id == id) {
	client = mc->soc->clients[i].name;
	break;
	}
	}

	type = (value & MC_ERR_STATUS_TYPE_MASK) >>
	MC_ERR_STATUS_TYPE_SHIFT;
	desc = error_names[type];

	switch (value & MC_ERR_STATUS_TYPE_MASK) {
	case MC_ERR_STATUS_TYPE_INVALID_SMMU_PAGE:
	perm[0] = ' ';
	perm[1] = '[';

	if (value & MC_ERR_STATUS_READABLE)
	perm[2] = 'R';
	else
	perm[2] = '-';

	if (value & MC_ERR_STATUS_WRITABLE)
	perm[3] = 'W';
	else
	perm[3] = '-';

	if (value & MC_ERR_STATUS_NONSECURE)
	perm[4] = '-';
	else
	perm[4] = 'S';

	perm[5] = ']';
	perm[6] = '\0';
	break;

	default:
	perm[0] = '\0';
	break;
	}

	value = mc_readl(mc, MC_ERR_ADR);
	addr \|= value;

	dev_err_ratelimited(mc->dev, "%s: %s%s @%pa: %s (%s%s)\n",
	client, secure, direction, &addr, error,
	desc, perm);
	}

	/* clear interrupts */
	mc_writel(mc, status, MC_INTSTATUS);

	return IRQ_HANDLED;
	}

	static int tegra_mc_probe(struct platform_device *pdev)
	{
	const struct of_device_id *match;
	struct resource *res;
	struct tegra_mc *mc;
	u32 value;
	int err;

	match = of_match_node(tegra_mc_of_match, pdev->dev.of_node);
	if (!match)
	return -ENODEV;

	mc = devm_kzalloc(&pdev->dev, sizeof(*mc), GFP_KERNEL);
	if (!mc)
	return -ENOMEM;

	platform_set_drvdata(pdev, mc);
	mc->soc = match->data;
	mc->dev = &pdev->dev;

	/* length of MC tick in nanoseconds */
	mc->tick = 30;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	mc->regs = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(mc->regs))
	return PTR_ERR(mc->regs);

	mc->clk = devm_clk_get(&pdev->dev, "mc");
	if (IS_ERR(mc->clk)) {
	dev_err(&pdev->dev, "failed to get MC clock: %ld\n",
	PTR_ERR(mc->clk));
	return PTR_ERR(mc->clk);
	}

	err = tegra_mc_setup_latency_allowance(mc);
	if (err < 0) {
	dev_err(&pdev->dev, "failed to setup latency allowance: %d\n",
	err);
	return err;
	}

	err = tegra_mc_setup_timings(mc);
	if (err < 0) {
	dev_err(&pdev->dev, "failed to setup timings: %d\n", err);
	return err;
	}

	if (IS_ENABLED(CONFIG_TEGRA_IOMMU_SMMU)) {
	mc->smmu = tegra_smmu_probe(&pdev->dev, mc->soc->smmu, mc);
	if (IS_ERR(mc->smmu)) {
	dev_err(&pdev->dev, "failed to probe SMMU: %ld\n",
	PTR_ERR(mc->smmu));
	return PTR_ERR(mc->smmu);
	}
	}

	mc->irq = platform_get_irq(pdev, 0);
	if (mc->irq < 0) {
	dev_err(&pdev->dev, "interrupt not specified\n");
	return mc->irq;
	}

	err = devm_request_irq(&pdev->dev, mc->irq, tegra_mc_irq, IRQF_SHARED,
	dev_name(&pdev->dev), mc);
	if (err < 0) {
	dev_err(&pdev->dev, "failed to request IRQ#%u: %d\n", mc->irq,
	err);
	return err;
	}

	WARN(!mc->soc->client_id_mask, "Missing client ID mask for this SoC\n");

	value = MC_INT_DECERR_MTS \| MC_INT_SECERR_SEC \| MC_INT_DECERR_VPR \|
	MC_INT_INVALID_APB_ASID_UPDATE \| MC_INT_INVALID_SMMU_PAGE \|
	MC_INT_SECURITY_VIOLATION \| MC_INT_DECERR_EMEM;

	mc_writel(mc, value, MC_INTMASK);

	return 0;
	}

	static struct platform_driver tegra_mc_driver = {
	.driver = {
	.name = "tegra-mc",
	.of_match_table = tegra_mc_of_match,
	.suppress_bind_attrs = true,
	},
	.prevent_deferred_probe = true,
	.probe = tegra_mc_probe,
	};

	static int tegra_mc_init(void)
	{
	return platform_driver_register(&tegra_mc_driver);
	}
	arch_initcall(tegra_mc_init);

	MODULE_AUTHOR("Thierry Reding <treding@nvidia.com>");
	MODULE_DESCRIPTION("NVIDIA Tegra Memory Controller driver");
	MODULE_LICENSE("GPL v2");