blob: 44b4a4080920ea48230e3d2abbdbd34247eb0238 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2014 NVIDIA CORPORATION. All rights reserved.
*/
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/export.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/sort.h>
#include <soc/tegra/fuse.h>
#include "mc.h"
static const struct of_device_id tegra_mc_of_match[] = {
#ifdef CONFIG_ARCH_TEGRA_2x_SOC
{ .compatible = "nvidia,tegra20-mc-gart", .data = &tegra20_mc_soc },
#endif
#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
#ifdef CONFIG_ARCH_TEGRA_186_SOC
{ .compatible = "nvidia,tegra186-mc", .data = &tegra186_mc_soc },
#endif
#ifdef CONFIG_ARCH_TEGRA_194_SOC
{ .compatible = "nvidia,tegra194-mc", .data = &tegra194_mc_soc },
#endif
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, tegra_mc_of_match);
static void tegra_mc_devm_action_put_device(void *data)
{
struct tegra_mc *mc = data;
put_device(mc->dev);
}
/**
* devm_tegra_memory_controller_get() - get Tegra Memory Controller handle
* @dev: device pointer for the consumer device
*
* This function will search for the Memory Controller node in a device-tree
* and retrieve the Memory Controller handle.
*
* Return: ERR_PTR() on error or a valid pointer to a struct tegra_mc.
*/
struct tegra_mc *devm_tegra_memory_controller_get(struct device *dev)
{
struct platform_device *pdev;
struct device_node *np;
struct tegra_mc *mc;
int err;
np = of_parse_phandle(dev->of_node, "nvidia,memory-controller", 0);
if (!np)
return ERR_PTR(-ENOENT);
pdev = of_find_device_by_node(np);
of_node_put(np);
if (!pdev)
return ERR_PTR(-ENODEV);
mc = platform_get_drvdata(pdev);
if (!mc) {
put_device(&pdev->dev);
return ERR_PTR(-EPROBE_DEFER);
}
err = devm_add_action_or_reset(dev, tegra_mc_devm_action_put_device, mc);
if (err)
return ERR_PTR(err);
return mc;
}
EXPORT_SYMBOL_GPL(devm_tegra_memory_controller_get);
int tegra_mc_probe_device(struct tegra_mc *mc, struct device *dev)
{
if (mc->soc->ops && mc->soc->ops->probe_device)
return mc->soc->ops->probe_device(mc, dev);
return 0;
}
EXPORT_SYMBOL_GPL(tegra_mc_probe_device);
static int tegra_mc_block_dma_common(struct tegra_mc *mc,
const struct tegra_mc_reset *rst)
{
unsigned long flags;
u32 value;
spin_lock_irqsave(&mc->lock, flags);
value = mc_readl(mc, rst->control) | BIT(rst->bit);
mc_writel(mc, value, rst->control);
spin_unlock_irqrestore(&mc->lock, flags);
return 0;
}
static bool tegra_mc_dma_idling_common(struct tegra_mc *mc,
const struct tegra_mc_reset *rst)
{
return (mc_readl(mc, rst->status) & BIT(rst->bit)) != 0;
}
static int tegra_mc_unblock_dma_common(struct tegra_mc *mc,
const struct tegra_mc_reset *rst)
{
unsigned long flags;
u32 value;
spin_lock_irqsave(&mc->lock, flags);
value = mc_readl(mc, rst->control) & ~BIT(rst->bit);
mc_writel(mc, value, rst->control);
spin_unlock_irqrestore(&mc->lock, flags);
return 0;
}
static int tegra_mc_reset_status_common(struct tegra_mc *mc,
const struct tegra_mc_reset *rst)
{
return (mc_readl(mc, rst->control) & BIT(rst->bit)) != 0;
}
const struct tegra_mc_reset_ops tegra_mc_reset_ops_common = {
.block_dma = tegra_mc_block_dma_common,
.dma_idling = tegra_mc_dma_idling_common,
.unblock_dma = tegra_mc_unblock_dma_common,
.reset_status = tegra_mc_reset_status_common,
};
static inline struct tegra_mc *reset_to_mc(struct reset_controller_dev *rcdev)
{
return container_of(rcdev, struct tegra_mc, reset);
}
static const struct tegra_mc_reset *tegra_mc_reset_find(struct tegra_mc *mc,
unsigned long id)
{
unsigned int i;
for (i = 0; i < mc->soc->num_resets; i++)
if (mc->soc->resets[i].id == id)
return &mc->soc->resets[i];
return NULL;
}
static int tegra_mc_hotreset_assert(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct tegra_mc *mc = reset_to_mc(rcdev);
const struct tegra_mc_reset_ops *rst_ops;
const struct tegra_mc_reset *rst;
int retries = 500;
int err;
rst = tegra_mc_reset_find(mc, id);
if (!rst)
return -ENODEV;
rst_ops = mc->soc->reset_ops;
if (!rst_ops)
return -ENODEV;
/* DMA flushing will fail if reset is already asserted */
if (rst_ops->reset_status) {
/* check whether reset is asserted */
if (rst_ops->reset_status(mc, rst))
return 0;
}
if (rst_ops->block_dma) {
/* block clients DMA requests */
err = rst_ops->block_dma(mc, rst);
if (err) {
dev_err(mc->dev, "failed to block %s DMA: %d\n",
rst->name, err);
return err;
}
}
if (rst_ops->dma_idling) {
/* wait for completion of the outstanding DMA requests */
while (!rst_ops->dma_idling(mc, rst)) {
if (!retries--) {
dev_err(mc->dev, "failed to flush %s DMA\n",
rst->name);
return -EBUSY;
}
usleep_range(10, 100);
}
}
if (rst_ops->hotreset_assert) {
/* clear clients DMA requests sitting before arbitration */
err = rst_ops->hotreset_assert(mc, rst);
if (err) {
dev_err(mc->dev, "failed to hot reset %s: %d\n",
rst->name, err);
return err;
}
}
return 0;
}
static int tegra_mc_hotreset_deassert(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct tegra_mc *mc = reset_to_mc(rcdev);
const struct tegra_mc_reset_ops *rst_ops;
const struct tegra_mc_reset *rst;
int err;
rst = tegra_mc_reset_find(mc, id);
if (!rst)
return -ENODEV;
rst_ops = mc->soc->reset_ops;
if (!rst_ops)
return -ENODEV;
if (rst_ops->hotreset_deassert) {
/* take out client from hot reset */
err = rst_ops->hotreset_deassert(mc, rst);
if (err) {
dev_err(mc->dev, "failed to deassert hot reset %s: %d\n",
rst->name, err);
return err;
}
}
if (rst_ops->unblock_dma) {
/* allow new DMA requests to proceed to arbitration */
err = rst_ops->unblock_dma(mc, rst);
if (err) {
dev_err(mc->dev, "failed to unblock %s DMA : %d\n",
rst->name, err);
return err;
}
}
return 0;
}
static int tegra_mc_hotreset_status(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct tegra_mc *mc = reset_to_mc(rcdev);
const struct tegra_mc_reset_ops *rst_ops;
const struct tegra_mc_reset *rst;
rst = tegra_mc_reset_find(mc, id);
if (!rst)
return -ENODEV;
rst_ops = mc->soc->reset_ops;
if (!rst_ops)
return -ENODEV;
return rst_ops->reset_status(mc, rst);
}
static const struct reset_control_ops tegra_mc_reset_ops = {
.assert = tegra_mc_hotreset_assert,
.deassert = tegra_mc_hotreset_deassert,
.status = tegra_mc_hotreset_status,
};
static int tegra_mc_reset_setup(struct tegra_mc *mc)
{
int err;
mc->reset.ops = &tegra_mc_reset_ops;
mc->reset.owner = THIS_MODULE;
mc->reset.of_node = mc->dev->of_node;
mc->reset.of_reset_n_cells = 1;
mc->reset.nr_resets = mc->soc->num_resets;
err = reset_controller_register(&mc->reset);
if (err < 0)
return err;
return 0;
}
int 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 -EINVAL;
}
for (i = 0; i < mc->soc->num_emem_regs; ++i)
mc_writel(mc, timing->emem_data[i], mc->soc->emem_regs[i]);
return 0;
}
EXPORT_SYMBOL_GPL(tegra_mc_write_emem_configuration);
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;
}
EXPORT_SYMBOL_GPL(tegra_mc_get_emem_device_count);
#if defined(CONFIG_ARCH_TEGRA_3x_SOC) || \
defined(CONFIG_ARCH_TEGRA_114_SOC) || \
defined(CONFIG_ARCH_TEGRA_124_SOC) || \
defined(CONFIG_ARCH_TEGRA_132_SOC) || \
defined(CONFIG_ARCH_TEGRA_210_SOC)
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 = (unsigned long long)mc->tick * clk_get_rate(mc->clk);
do_div(tick, NSEC_PER_SEC);
value = mc_readl(mc, MC_EMEM_ARB_CFG);
value &= ~MC_EMEM_ARB_CFG_CYCLES_PER_UPDATE_MASK;
value |= MC_EMEM_ARB_CFG_CYCLES_PER_UPDATE(tick);
mc_writel(mc, value, MC_EMEM_ARB_CFG);
/* write latency allowance defaults */
for (i = 0; i < mc->soc->num_clients; i++) {
const struct tegra_mc_client *client = &mc->soc->clients[i];
u32 value;
value = mc_readl(mc, client->regs.la.reg);
value &= ~(client->regs.la.mask << client->regs.la.shift);
value |= (client->regs.la.def & client->regs.la.mask) << client->regs.la.shift;
mc_writel(mc, value, client->regs.la.reg);
}
/* latch new values */
mc_writel(mc, MC_TIMING_UPDATE, MC_TIMING_CONTROL);
return 0;
}
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 %pOFn: failed to read rate\n", node);
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 %pOFn: failed to read EMEM configuration\n",
node);
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) {
of_node_put(child);
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))
continue;
err = load_timings(mc, node);
of_node_put(node);
if (err)
return err;
break;
}
if (mc->num_timings == 0)
dev_warn(mc->dev,
"no memory timings for RAM code %u registered\n",
ram_code);
return 0;
}
int tegra30_mc_probe(struct tegra_mc *mc)
{
int err;
mc->clk = devm_clk_get_optional(mc->dev, "mc");
if (IS_ERR(mc->clk)) {
dev_err(mc->dev, "failed to get MC clock: %ld\n", PTR_ERR(mc->clk));
return PTR_ERR(mc->clk);
}
/* ensure that debug features are disabled */
mc_writel(mc, 0x00000000, MC_TIMING_CONTROL_DBG);
err = tegra_mc_setup_latency_allowance(mc);
if (err < 0) {
dev_err(mc->dev, "failed to setup latency allowance: %d\n", err);
return err;
}
err = tegra_mc_setup_timings(mc);
if (err < 0) {
dev_err(mc->dev, "failed to setup timings: %d\n", err);
return err;
}
return 0;
}
static irqreturn_t tegra30_mc_handle_irq(int irq, void *data)
{
struct tegra_mc *mc = data;
unsigned long status;
unsigned int bit;
/* mask all interrupts to avoid flooding */
status = mc_readl(mc, MC_INTSTATUS) & mc->soc->intmask;
if (!status)
return IRQ_NONE;
for_each_set_bit(bit, &status, 32) {
const char *error = tegra_mc_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 = tegra_mc_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;
}
const struct tegra_mc_ops tegra30_mc_ops = {
.probe = tegra30_mc_probe,
.handle_irq = tegra30_mc_handle_irq,
};
#endif
const char *const tegra_mc_status_names[32] = {
[ 1] = "External interrupt",
[ 6] = "EMEM address decode error",
[ 7] = "GART page fault",
[ 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",
};
const char *const tegra_mc_error_names[8] = {
[2] = "EMEM decode error",
[3] = "TrustZone violation",
[4] = "Carveout violation",
[6] = "SMMU translation error",
};
/*
* Memory Controller (MC) has few Memory Clients that are issuing memory
* bandwidth allocation requests to the MC interconnect provider. The MC
* provider aggregates the requests and then sends the aggregated request
* up to the External Memory Controller (EMC) interconnect provider which
* re-configures hardware interface to External Memory (EMEM) in accordance
* to the required bandwidth. Each MC interconnect node represents an
* individual Memory Client.
*
* Memory interconnect topology:
*
* +----+
* +--------+ | |
* | TEXSRD +--->+ |
* +--------+ | |
* | | +-----+ +------+
* ... | MC +--->+ EMC +--->+ EMEM |
* | | +-----+ +------+
* +--------+ | |
* | DISP.. +--->+ |
* +--------+ | |
* +----+
*/
static int tegra_mc_interconnect_setup(struct tegra_mc *mc)
{
struct icc_node *node;
unsigned int i;
int err;
/* older device-trees don't have interconnect properties */
if (!device_property_present(mc->dev, "#interconnect-cells") ||
!mc->soc->icc_ops)
return 0;
mc->provider.dev = mc->dev;
mc->provider.data = &mc->provider;
mc->provider.set = mc->soc->icc_ops->set;
mc->provider.aggregate = mc->soc->icc_ops->aggregate;
mc->provider.xlate_extended = mc->soc->icc_ops->xlate_extended;
err = icc_provider_add(&mc->provider);
if (err)
return err;
/* create Memory Controller node */
node = icc_node_create(TEGRA_ICC_MC);
if (IS_ERR(node)) {
err = PTR_ERR(node);
goto del_provider;
}
node->name = "Memory Controller";
icc_node_add(node, &mc->provider);
/* link Memory Controller to External Memory Controller */
err = icc_link_create(node, TEGRA_ICC_EMC);
if (err)
goto remove_nodes;
for (i = 0; i < mc->soc->num_clients; i++) {
/* create MC client node */
node = icc_node_create(mc->soc->clients[i].id);
if (IS_ERR(node)) {
err = PTR_ERR(node);
goto remove_nodes;
}
node->name = mc->soc->clients[i].name;
icc_node_add(node, &mc->provider);
/* link Memory Client to Memory Controller */
err = icc_link_create(node, TEGRA_ICC_MC);
if (err)
goto remove_nodes;
}
return 0;
remove_nodes:
icc_nodes_remove(&mc->provider);
del_provider:
icc_provider_del(&mc->provider);
return err;
}
static int tegra_mc_probe(struct platform_device *pdev)
{
struct resource *res;
struct tegra_mc *mc;
u64 mask;
int err;
mc = devm_kzalloc(&pdev->dev, sizeof(*mc), GFP_KERNEL);
if (!mc)
return -ENOMEM;
platform_set_drvdata(pdev, mc);
spin_lock_init(&mc->lock);
mc->soc = of_device_get_match_data(&pdev->dev);
mc->dev = &pdev->dev;
mask = DMA_BIT_MASK(mc->soc->num_address_bits);
err = dma_coerce_mask_and_coherent(&pdev->dev, mask);
if (err < 0) {
dev_err(&pdev->dev, "failed to set DMA mask: %d\n", err);
return err;
}
/* 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->debugfs.root = debugfs_create_dir("mc", NULL);
if (mc->soc->ops && mc->soc->ops->probe) {
err = mc->soc->ops->probe(mc);
if (err < 0)
return err;
}
if (mc->soc->ops && mc->soc->ops->handle_irq) {
mc->irq = platform_get_irq(pdev, 0);
if (mc->irq < 0)
return mc->irq;
WARN(!mc->soc->client_id_mask, "missing client ID mask for this SoC\n");
mc_writel(mc, mc->soc->intmask, MC_INTMASK);
err = devm_request_irq(&pdev->dev, mc->irq, mc->soc->ops->handle_irq, 0,
dev_name(&pdev->dev), mc);
if (err < 0) {
dev_err(&pdev->dev, "failed to request IRQ#%u: %d\n", mc->irq,
err);
return err;
}
}
if (mc->soc->reset_ops) {
err = tegra_mc_reset_setup(mc);
if (err < 0)
dev_err(&pdev->dev, "failed to register reset controller: %d\n", err);
}
err = tegra_mc_interconnect_setup(mc);
if (err < 0)
dev_err(&pdev->dev, "failed to initialize interconnect: %d\n",
err);
if (IS_ENABLED(CONFIG_TEGRA_IOMMU_SMMU) && mc->soc->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));
mc->smmu = NULL;
}
}
if (IS_ENABLED(CONFIG_TEGRA_IOMMU_GART) && !mc->soc->smmu) {
mc->gart = tegra_gart_probe(&pdev->dev, mc);
if (IS_ERR(mc->gart)) {
dev_err(&pdev->dev, "failed to probe GART: %ld\n",
PTR_ERR(mc->gart));
mc->gart = NULL;
}
}
return 0;
}
static int __maybe_unused tegra_mc_suspend(struct device *dev)
{
struct tegra_mc *mc = dev_get_drvdata(dev);
if (mc->soc->ops && mc->soc->ops->suspend)
return mc->soc->ops->suspend(mc);
return 0;
}
static int __maybe_unused tegra_mc_resume(struct device *dev)
{
struct tegra_mc *mc = dev_get_drvdata(dev);
if (mc->soc->ops && mc->soc->ops->resume)
return mc->soc->ops->resume(mc);
return 0;
}
static void tegra_mc_sync_state(struct device *dev)
{
struct tegra_mc *mc = dev_get_drvdata(dev);
/* check whether ICC provider is registered */
if (mc->provider.dev == dev)
icc_sync_state(dev);
}
static const struct dev_pm_ops tegra_mc_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(tegra_mc_suspend, tegra_mc_resume)
};
static struct platform_driver tegra_mc_driver = {
.driver = {
.name = "tegra-mc",
.of_match_table = tegra_mc_of_match,
.pm = &tegra_mc_pm_ops,
.suppress_bind_attrs = true,
.sync_state = tegra_mc_sync_state,
},
.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");