memory: tegra: Changes for v5.6-rc1

This adds a couple of fixes for the Tegra30 EMC frequency scaling code
 and adds support for EMC frequency scaling on Tegra186 and later.
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Merge tag 'tegra-for-5.6-memory' of git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux into arm/drivers

memory: tegra: Changes for v5.6-rc1

This adds a couple of fixes for the Tegra30 EMC frequency scaling code
and adds support for EMC frequency scaling on Tegra186 and later.

* tag 'tegra-for-5.6-memory' of git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux:
  memory: tegra30-emc: Correct error message for timed out auto calibration
  memory: tegra30-emc: Firm up hardware programming sequence
  memory: tegra30-emc: Firm up suspend/resume sequence
  memory: tegra: Correct reset value of xusb_hostr
  memory: tegra: Add support for the Tegra194 memory controller
  memory: tegra: Only include support for enabled SoCs
  memory: tegra: Support DVFS on Tegra186 and later
  memory: tegra: Add system sleep support
  memory: tegra: Extract memory client SID programming
  memory: tegra: Add per-SoC data for Tegra186
  memory: tegra: Rename tegra_mc to tegra186_mc on Tegra186
  memory: tegra: Implement EMC debugfs interface on Tegra30
  memory: tegra: Implement EMC debugfs interface on Tegra20
  memory: tegra: Refashion EMC debugfs interface on Tegra124

Link: https://lore.kernel.org/r/20200111003553.2411874-3-thierry.reding@gmail.com
Signed-off-by: Olof Johansson <olof@lixom.net>
This commit is contained in:
Olof Johansson 2020-01-16 10:41:47 -08:00
commit 083b4db857
7 changed files with 1932 additions and 153 deletions

View file

@ -13,4 +13,5 @@ obj-$(CONFIG_TEGRA_MC) += tegra-mc.o
obj-$(CONFIG_TEGRA20_EMC) += tegra20-emc.o
obj-$(CONFIG_TEGRA30_EMC) += tegra30-emc.o
obj-$(CONFIG_TEGRA124_EMC) += tegra124-emc.o
obj-$(CONFIG_ARCH_TEGRA_186_SOC) += tegra186.o
obj-$(CONFIG_ARCH_TEGRA_186_SOC) += tegra186.o tegra186-emc.o
obj-$(CONFIG_ARCH_TEGRA_194_SOC) += tegra186.o tegra186-emc.o

View file

@ -467,12 +467,20 @@ struct tegra_emc {
void __iomem *regs;
struct clk *clk;
enum emc_dram_type dram_type;
unsigned int dram_num;
struct emc_timing last_timing;
struct emc_timing *timings;
unsigned int num_timings;
struct {
struct dentry *root;
unsigned long min_rate;
unsigned long max_rate;
} debugfs;
};
/* Timing change sequence functions */
@ -998,38 +1006,51 @@ tegra_emc_find_node_by_ram_code(struct device_node *node, u32 ram_code)
return NULL;
}
/* Debugfs entry */
/*
* debugfs interface
*
* The memory controller driver exposes some files in debugfs that can be used
* to control the EMC frequency. The top-level directory can be found here:
*
* /sys/kernel/debug/emc
*
* It contains the following files:
*
* - available_rates: This file contains a list of valid, space-separated
* EMC frequencies.
*
* - min_rate: Writing a value to this file sets the given frequency as the
* floor of the permitted range. If this is higher than the currently
* configured EMC frequency, this will cause the frequency to be
* increased so that it stays within the valid range.
*
* - max_rate: Similarily to the min_rate file, writing a value to this file
* sets the given frequency as the ceiling of the permitted range. If
* the value is lower than the currently configured EMC frequency, this
* will cause the frequency to be decreased so that it stays within the
* valid range.
*/
static int emc_debug_rate_get(void *data, u64 *rate)
static bool tegra_emc_validate_rate(struct tegra_emc *emc, unsigned long rate)
{
struct clk *c = data;
unsigned int i;
*rate = clk_get_rate(c);
for (i = 0; i < emc->num_timings; i++)
if (rate == emc->timings[i].rate)
return true;
return 0;
return false;
}
static int emc_debug_rate_set(void *data, u64 rate)
{
struct clk *c = data;
return clk_set_rate(c, rate);
}
DEFINE_SIMPLE_ATTRIBUTE(emc_debug_rate_fops, emc_debug_rate_get,
emc_debug_rate_set, "%lld\n");
static int emc_debug_supported_rates_show(struct seq_file *s, void *data)
static int tegra_emc_debug_available_rates_show(struct seq_file *s,
void *data)
{
struct tegra_emc *emc = s->private;
const char *prefix = "";
unsigned int i;
for (i = 0; i < emc->num_timings; i++) {
struct emc_timing *timing = &emc->timings[i];
seq_printf(s, "%s%lu", prefix, timing->rate);
seq_printf(s, "%s%lu", prefix, emc->timings[i].rate);
prefix = " ";
}
@ -1038,46 +1059,126 @@ static int emc_debug_supported_rates_show(struct seq_file *s, void *data)
return 0;
}
static int emc_debug_supported_rates_open(struct inode *inode,
struct file *file)
static int tegra_emc_debug_available_rates_open(struct inode *inode,
struct file *file)
{
return single_open(file, emc_debug_supported_rates_show,
return single_open(file, tegra_emc_debug_available_rates_show,
inode->i_private);
}
static const struct file_operations emc_debug_supported_rates_fops = {
.open = emc_debug_supported_rates_open,
static const struct file_operations tegra_emc_debug_available_rates_fops = {
.open = tegra_emc_debug_available_rates_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int tegra_emc_debug_min_rate_get(void *data, u64 *rate)
{
struct tegra_emc *emc = data;
*rate = emc->debugfs.min_rate;
return 0;
}
static int tegra_emc_debug_min_rate_set(void *data, u64 rate)
{
struct tegra_emc *emc = data;
int err;
if (!tegra_emc_validate_rate(emc, rate))
return -EINVAL;
err = clk_set_min_rate(emc->clk, rate);
if (err < 0)
return err;
emc->debugfs.min_rate = rate;
return 0;
}
DEFINE_SIMPLE_ATTRIBUTE(tegra_emc_debug_min_rate_fops,
tegra_emc_debug_min_rate_get,
tegra_emc_debug_min_rate_set, "%llu\n");
static int tegra_emc_debug_max_rate_get(void *data, u64 *rate)
{
struct tegra_emc *emc = data;
*rate = emc->debugfs.max_rate;
return 0;
}
static int tegra_emc_debug_max_rate_set(void *data, u64 rate)
{
struct tegra_emc *emc = data;
int err;
if (!tegra_emc_validate_rate(emc, rate))
return -EINVAL;
err = clk_set_max_rate(emc->clk, rate);
if (err < 0)
return err;
emc->debugfs.max_rate = rate;
return 0;
}
DEFINE_SIMPLE_ATTRIBUTE(tegra_emc_debug_max_rate_fops,
tegra_emc_debug_max_rate_get,
tegra_emc_debug_max_rate_set, "%llu\n");
static void emc_debugfs_init(struct device *dev, struct tegra_emc *emc)
{
struct dentry *root, *file;
struct clk *clk;
unsigned int i;
int err;
root = debugfs_create_dir("emc", NULL);
if (!root) {
emc->clk = devm_clk_get(dev, "emc");
if (IS_ERR(emc->clk)) {
if (PTR_ERR(emc->clk) != -ENODEV) {
dev_err(dev, "failed to get EMC clock: %ld\n",
PTR_ERR(emc->clk));
return;
}
}
emc->debugfs.min_rate = ULONG_MAX;
emc->debugfs.max_rate = 0;
for (i = 0; i < emc->num_timings; i++) {
if (emc->timings[i].rate < emc->debugfs.min_rate)
emc->debugfs.min_rate = emc->timings[i].rate;
if (emc->timings[i].rate > emc->debugfs.max_rate)
emc->debugfs.max_rate = emc->timings[i].rate;
}
err = clk_set_rate_range(emc->clk, emc->debugfs.min_rate,
emc->debugfs.max_rate);
if (err < 0) {
dev_err(dev, "failed to set rate range [%lu-%lu] for %pC\n",
emc->debugfs.min_rate, emc->debugfs.max_rate,
emc->clk);
return;
}
emc->debugfs.root = debugfs_create_dir("emc", NULL);
if (!emc->debugfs.root) {
dev_err(dev, "failed to create debugfs directory\n");
return;
}
clk = clk_get_sys("tegra-clk-debug", "emc");
if (IS_ERR(clk)) {
dev_err(dev, "failed to get debug clock: %ld\n", PTR_ERR(clk));
return;
}
file = debugfs_create_file("rate", S_IRUGO | S_IWUSR, root, clk,
&emc_debug_rate_fops);
if (!file)
dev_err(dev, "failed to create debugfs entry\n");
file = debugfs_create_file("supported_rates", S_IRUGO, root, emc,
&emc_debug_supported_rates_fops);
if (!file)
dev_err(dev, "failed to create debugfs entry\n");
debugfs_create_file("available_rates", S_IRUGO, emc->debugfs.root, emc,
&tegra_emc_debug_available_rates_fops);
debugfs_create_file("min_rate", S_IRUGO | S_IWUSR, emc->debugfs.root,
emc, &tegra_emc_debug_min_rate_fops);
debugfs_create_file("max_rate", S_IRUGO | S_IWUSR, emc->debugfs.root,
emc, &tegra_emc_debug_max_rate_fops);
}
static int tegra_emc_probe(struct platform_device *pdev)

View file

@ -0,0 +1,293 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2019 NVIDIA CORPORATION. All rights reserved.
*/
#include <linux/clk.h>
#include <linux/debugfs.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/platform_device.h>
#include <soc/tegra/bpmp.h>
struct tegra186_emc_dvfs {
unsigned long latency;
unsigned long rate;
};
struct tegra186_emc {
struct tegra_bpmp *bpmp;
struct device *dev;
struct clk *clk;
struct tegra186_emc_dvfs *dvfs;
unsigned int num_dvfs;
struct {
struct dentry *root;
unsigned long min_rate;
unsigned long max_rate;
} debugfs;
};
/*
* debugfs interface
*
* The memory controller driver exposes some files in debugfs that can be used
* to control the EMC frequency. The top-level directory can be found here:
*
* /sys/kernel/debug/emc
*
* It contains the following files:
*
* - available_rates: This file contains a list of valid, space-separated
* EMC frequencies.
*
* - min_rate: Writing a value to this file sets the given frequency as the
* floor of the permitted range. If this is higher than the currently
* configured EMC frequency, this will cause the frequency to be
* increased so that it stays within the valid range.
*
* - max_rate: Similarily to the min_rate file, writing a value to this file
* sets the given frequency as the ceiling of the permitted range. If
* the value is lower than the currently configured EMC frequency, this
* will cause the frequency to be decreased so that it stays within the
* valid range.
*/
static bool tegra186_emc_validate_rate(struct tegra186_emc *emc,
unsigned long rate)
{
unsigned int i;
for (i = 0; i < emc->num_dvfs; i++)
if (rate == emc->dvfs[i].rate)
return true;
return false;
}
static int tegra186_emc_debug_available_rates_show(struct seq_file *s,
void *data)
{
struct tegra186_emc *emc = s->private;
const char *prefix = "";
unsigned int i;
for (i = 0; i < emc->num_dvfs; i++) {
seq_printf(s, "%s%lu", prefix, emc->dvfs[i].rate);
prefix = " ";
}
seq_puts(s, "\n");
return 0;
}
static int tegra186_emc_debug_available_rates_open(struct inode *inode,
struct file *file)
{
return single_open(file, tegra186_emc_debug_available_rates_show,
inode->i_private);
}
static const struct file_operations tegra186_emc_debug_available_rates_fops = {
.open = tegra186_emc_debug_available_rates_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int tegra186_emc_debug_min_rate_get(void *data, u64 *rate)
{
struct tegra186_emc *emc = data;
*rate = emc->debugfs.min_rate;
return 0;
}
static int tegra186_emc_debug_min_rate_set(void *data, u64 rate)
{
struct tegra186_emc *emc = data;
int err;
if (!tegra186_emc_validate_rate(emc, rate))
return -EINVAL;
err = clk_set_min_rate(emc->clk, rate);
if (err < 0)
return err;
emc->debugfs.min_rate = rate;
return 0;
}
DEFINE_SIMPLE_ATTRIBUTE(tegra186_emc_debug_min_rate_fops,
tegra186_emc_debug_min_rate_get,
tegra186_emc_debug_min_rate_set, "%llu\n");
static int tegra186_emc_debug_max_rate_get(void *data, u64 *rate)
{
struct tegra186_emc *emc = data;
*rate = emc->debugfs.max_rate;
return 0;
}
static int tegra186_emc_debug_max_rate_set(void *data, u64 rate)
{
struct tegra186_emc *emc = data;
int err;
if (!tegra186_emc_validate_rate(emc, rate))
return -EINVAL;
err = clk_set_max_rate(emc->clk, rate);
if (err < 0)
return err;
emc->debugfs.max_rate = rate;
return 0;
}
DEFINE_SIMPLE_ATTRIBUTE(tegra186_emc_debug_max_rate_fops,
tegra186_emc_debug_max_rate_get,
tegra186_emc_debug_max_rate_set, "%llu\n");
static int tegra186_emc_probe(struct platform_device *pdev)
{
struct mrq_emc_dvfs_latency_response response;
struct tegra_bpmp_message msg;
struct tegra186_emc *emc;
unsigned int i;
int err;
emc = devm_kzalloc(&pdev->dev, sizeof(*emc), GFP_KERNEL);
if (!emc)
return -ENOMEM;
emc->bpmp = tegra_bpmp_get(&pdev->dev);
if (IS_ERR(emc->bpmp)) {
err = PTR_ERR(emc->bpmp);
if (err != -EPROBE_DEFER)
dev_err(&pdev->dev, "failed to get BPMP: %d\n", err);
return err;
}
emc->clk = devm_clk_get(&pdev->dev, "emc");
if (IS_ERR(emc->clk)) {
err = PTR_ERR(emc->clk);
dev_err(&pdev->dev, "failed to get EMC clock: %d\n", err);
return err;
}
platform_set_drvdata(pdev, emc);
emc->dev = &pdev->dev;
memset(&msg, 0, sizeof(msg));
msg.mrq = MRQ_EMC_DVFS_LATENCY;
msg.tx.data = NULL;
msg.tx.size = 0;
msg.rx.data = &response;
msg.rx.size = sizeof(response);
err = tegra_bpmp_transfer(emc->bpmp, &msg);
if (err < 0) {
dev_err(&pdev->dev, "failed to EMC DVFS pairs: %d\n", err);
return err;
}
emc->debugfs.min_rate = ULONG_MAX;
emc->debugfs.max_rate = 0;
emc->num_dvfs = response.num_pairs;
emc->dvfs = devm_kmalloc_array(&pdev->dev, emc->num_dvfs,
sizeof(*emc->dvfs), GFP_KERNEL);
if (!emc->dvfs)
return -ENOMEM;
dev_dbg(&pdev->dev, "%u DVFS pairs:\n", emc->num_dvfs);
for (i = 0; i < emc->num_dvfs; i++) {
emc->dvfs[i].rate = response.pairs[i].freq * 1000;
emc->dvfs[i].latency = response.pairs[i].latency;
if (emc->dvfs[i].rate < emc->debugfs.min_rate)
emc->debugfs.min_rate = emc->dvfs[i].rate;
if (emc->dvfs[i].rate > emc->debugfs.max_rate)
emc->debugfs.max_rate = emc->dvfs[i].rate;
dev_dbg(&pdev->dev, " %2u: %lu Hz -> %lu us\n", i,
emc->dvfs[i].rate, emc->dvfs[i].latency);
}
err = clk_set_rate_range(emc->clk, emc->debugfs.min_rate,
emc->debugfs.max_rate);
if (err < 0) {
dev_err(&pdev->dev,
"failed to set rate range [%lu-%lu] for %pC\n",
emc->debugfs.min_rate, emc->debugfs.max_rate,
emc->clk);
return err;
}
emc->debugfs.root = debugfs_create_dir("emc", NULL);
if (!emc->debugfs.root) {
dev_err(&pdev->dev, "failed to create debugfs directory\n");
return 0;
}
debugfs_create_file("available_rates", S_IRUGO, emc->debugfs.root,
emc, &tegra186_emc_debug_available_rates_fops);
debugfs_create_file("min_rate", S_IRUGO | S_IWUSR, emc->debugfs.root,
emc, &tegra186_emc_debug_min_rate_fops);
debugfs_create_file("max_rate", S_IRUGO | S_IWUSR, emc->debugfs.root,
emc, &tegra186_emc_debug_max_rate_fops);
return 0;
}
static int tegra186_emc_remove(struct platform_device *pdev)
{
struct tegra186_emc *emc = platform_get_drvdata(pdev);
debugfs_remove_recursive(emc->debugfs.root);
tegra_bpmp_put(emc->bpmp);
return 0;
}
static const struct of_device_id tegra186_emc_of_match[] = {
#if defined(CONFIG_ARCH_TEGRA186_SOC)
{ .compatible = "nvidia,tegra186-emc" },
#endif
#if defined(CONFIG_ARCH_TEGRA194_SOC)
{ .compatible = "nvidia,tegra194-emc" },
#endif
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, tegra186_emc_of_match);
static struct platform_driver tegra186_emc_driver = {
.driver = {
.name = "tegra186-emc",
.of_match_table = tegra186_emc_of_match,
.suppress_bind_attrs = true,
},
.probe = tegra186_emc_probe,
.remove = tegra186_emc_remove,
};
module_platform_driver(tegra186_emc_driver);
MODULE_AUTHOR("Thierry Reding <treding@nvidia.com>");
MODULE_DESCRIPTION("NVIDIA Tegra186 External Memory Controller driver");
MODULE_LICENSE("GPL v2");

File diff suppressed because it is too large Load diff

View file

@ -8,6 +8,7 @@
#include <linux/clk.h>
#include <linux/clk/tegra.h>
#include <linux/completion.h>
#include <linux/debugfs.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/io.h>
@ -150,6 +151,12 @@ struct tegra_emc {
struct emc_timing *timings;
unsigned int num_timings;
struct {
struct dentry *root;
unsigned long min_rate;
unsigned long max_rate;
} debugfs;
};
static irqreturn_t tegra_emc_isr(int irq, void *data)
@ -478,6 +485,171 @@ static long emc_round_rate(unsigned long rate,
return timing->rate;
}
/*
* debugfs interface
*
* The memory controller driver exposes some files in debugfs that can be used
* to control the EMC frequency. The top-level directory can be found here:
*
* /sys/kernel/debug/emc
*
* It contains the following files:
*
* - available_rates: This file contains a list of valid, space-separated
* EMC frequencies.
*
* - min_rate: Writing a value to this file sets the given frequency as the
* floor of the permitted range. If this is higher than the currently
* configured EMC frequency, this will cause the frequency to be
* increased so that it stays within the valid range.
*
* - max_rate: Similarily to the min_rate file, writing a value to this file
* sets the given frequency as the ceiling of the permitted range. If
* the value is lower than the currently configured EMC frequency, this
* will cause the frequency to be decreased so that it stays within the
* valid range.
*/
static bool tegra_emc_validate_rate(struct tegra_emc *emc, unsigned long rate)
{
unsigned int i;
for (i = 0; i < emc->num_timings; i++)
if (rate == emc->timings[i].rate)
return true;
return false;
}
static int tegra_emc_debug_available_rates_show(struct seq_file *s, void *data)
{
struct tegra_emc *emc = s->private;
const char *prefix = "";
unsigned int i;
for (i = 0; i < emc->num_timings; i++) {
seq_printf(s, "%s%lu", prefix, emc->timings[i].rate);
prefix = " ";
}
seq_puts(s, "\n");
return 0;
}
static int tegra_emc_debug_available_rates_open(struct inode *inode,
struct file *file)
{
return single_open(file, tegra_emc_debug_available_rates_show,
inode->i_private);
}
static const struct file_operations tegra_emc_debug_available_rates_fops = {
.open = tegra_emc_debug_available_rates_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int tegra_emc_debug_min_rate_get(void *data, u64 *rate)
{
struct tegra_emc *emc = data;
*rate = emc->debugfs.min_rate;
return 0;
}
static int tegra_emc_debug_min_rate_set(void *data, u64 rate)
{
struct tegra_emc *emc = data;
int err;
if (!tegra_emc_validate_rate(emc, rate))
return -EINVAL;
err = clk_set_min_rate(emc->clk, rate);
if (err < 0)
return err;
emc->debugfs.min_rate = rate;
return 0;
}
DEFINE_SIMPLE_ATTRIBUTE(tegra_emc_debug_min_rate_fops,
tegra_emc_debug_min_rate_get,
tegra_emc_debug_min_rate_set, "%llu\n");
static int tegra_emc_debug_max_rate_get(void *data, u64 *rate)
{
struct tegra_emc *emc = data;
*rate = emc->debugfs.max_rate;
return 0;
}
static int tegra_emc_debug_max_rate_set(void *data, u64 rate)
{
struct tegra_emc *emc = data;
int err;
if (!tegra_emc_validate_rate(emc, rate))
return -EINVAL;
err = clk_set_max_rate(emc->clk, rate);
if (err < 0)
return err;
emc->debugfs.max_rate = rate;
return 0;
}
DEFINE_SIMPLE_ATTRIBUTE(tegra_emc_debug_max_rate_fops,
tegra_emc_debug_max_rate_get,
tegra_emc_debug_max_rate_set, "%llu\n");
static void tegra_emc_debugfs_init(struct tegra_emc *emc)
{
struct device *dev = emc->dev;
unsigned int i;
int err;
emc->debugfs.min_rate = ULONG_MAX;
emc->debugfs.max_rate = 0;
for (i = 0; i < emc->num_timings; i++) {
if (emc->timings[i].rate < emc->debugfs.min_rate)
emc->debugfs.min_rate = emc->timings[i].rate;
if (emc->timings[i].rate > emc->debugfs.max_rate)
emc->debugfs.max_rate = emc->timings[i].rate;
}
err = clk_set_rate_range(emc->clk, emc->debugfs.min_rate,
emc->debugfs.max_rate);
if (err < 0) {
dev_err(dev, "failed to set rate range [%lu-%lu] for %pC\n",
emc->debugfs.min_rate, emc->debugfs.max_rate,
emc->clk);
}
emc->debugfs.root = debugfs_create_dir("emc", NULL);
if (!emc->debugfs.root) {
dev_err(emc->dev, "failed to create debugfs directory\n");
return;
}
debugfs_create_file("available_rates", S_IRUGO, emc->debugfs.root,
emc, &tegra_emc_debug_available_rates_fops);
debugfs_create_file("min_rate", S_IRUGO | S_IWUSR, emc->debugfs.root,
emc, &tegra_emc_debug_min_rate_fops);
debugfs_create_file("max_rate", S_IRUGO | S_IWUSR, emc->debugfs.root,
emc, &tegra_emc_debug_max_rate_fops);
}
static int tegra_emc_probe(struct platform_device *pdev)
{
struct device_node *np;
@ -550,6 +722,9 @@ static int tegra_emc_probe(struct platform_device *pdev)
goto unset_cb;
}
platform_set_drvdata(pdev, emc);
tegra_emc_debugfs_init(emc);
return 0;
unset_cb:

View file

@ -436,7 +436,7 @@ static const struct tegra_mc_client tegra210_mc_clients[] = {
.reg = 0x37c,
.shift = 0,
.mask = 0xff,
.def = 0x39,
.def = 0x7a,
},
}, {
.id = 0x4b,

View file

@ -12,6 +12,7 @@
#include <linux/clk.h>
#include <linux/clk/tegra.h>
#include <linux/completion.h>
#include <linux/debugfs.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/interrupt.h>
@ -331,7 +332,9 @@ struct tegra_emc {
struct clk *clk;
void __iomem *regs;
unsigned int irq;
bool bad_state;
struct emc_timing *new_timing;
struct emc_timing *timings;
unsigned int num_timings;
@ -345,10 +348,74 @@ struct tegra_emc {
bool vref_cal_toggle : 1;
bool zcal_long : 1;
bool dll_on : 1;
bool prepared : 1;
bool bad_state : 1;
struct {
struct dentry *root;
unsigned long min_rate;
unsigned long max_rate;
} debugfs;
};
static int emc_seq_update_timing(struct tegra_emc *emc)
{
u32 val;
int err;
writel_relaxed(EMC_TIMING_UPDATE, emc->regs + EMC_TIMING_CONTROL);
err = readl_relaxed_poll_timeout_atomic(emc->regs + EMC_STATUS, val,
!(val & EMC_STATUS_TIMING_UPDATE_STALLED),
1, 200);
if (err) {
dev_err(emc->dev, "failed to update timing: %d\n", err);
return err;
}
return 0;
}
static void emc_complete_clk_change(struct tegra_emc *emc)
{
struct emc_timing *timing = emc->new_timing;
unsigned int dram_num;
bool failed = false;
int err;
/* re-enable auto-refresh */
dram_num = tegra_mc_get_emem_device_count(emc->mc);
writel_relaxed(EMC_REFCTRL_ENABLE_ALL(dram_num),
emc->regs + EMC_REFCTRL);
/* restore auto-calibration */
if (emc->vref_cal_toggle)
writel_relaxed(timing->emc_auto_cal_interval,
emc->regs + EMC_AUTO_CAL_INTERVAL);
/* restore dynamic self-refresh */
if (timing->emc_cfg_dyn_self_ref) {
emc->emc_cfg |= EMC_CFG_DYN_SREF_ENABLE;
writel_relaxed(emc->emc_cfg, emc->regs + EMC_CFG);
}
/* set number of clocks to wait after each ZQ command */
if (emc->zcal_long)
writel_relaxed(timing->emc_zcal_cnt_long,
emc->regs + EMC_ZCAL_WAIT_CNT);
/* wait for writes to settle */
udelay(2);
/* update restored timing */
err = emc_seq_update_timing(emc);
if (err)
failed = true;
/* restore early ACK */
mc_writel(emc->mc, emc->mc_override, MC_EMEM_ARB_OVERRIDE);
WRITE_ONCE(emc->bad_state, failed);
}
static irqreturn_t tegra_emc_isr(int irq, void *data)
{
struct tegra_emc *emc = data;
@ -359,10 +426,6 @@ static irqreturn_t tegra_emc_isr(int irq, void *data)
if (!status)
return IRQ_NONE;
/* notify about EMC-CAR handshake completion */
if (status & EMC_CLKCHANGE_COMPLETE_INT)
complete(&emc->clk_handshake_complete);
/* notify about HW problem */
if (status & EMC_REFRESH_OVERFLOW_INT)
dev_err_ratelimited(emc->dev,
@ -371,6 +434,18 @@ static irqreturn_t tegra_emc_isr(int irq, void *data)
/* clear interrupts */
writel_relaxed(status, emc->regs + EMC_INTSTATUS);
/* notify about EMC-CAR handshake completion */
if (status & EMC_CLKCHANGE_COMPLETE_INT) {
if (completion_done(&emc->clk_handshake_complete)) {
dev_err_ratelimited(emc->dev,
"bogus handshake interrupt\n");
return IRQ_NONE;
}
emc_complete_clk_change(emc);
complete(&emc->clk_handshake_complete);
}
return IRQ_HANDLED;
}
@ -438,24 +513,6 @@ static bool emc_dqs_preset(struct tegra_emc *emc, struct emc_timing *timing,
return preset;
}
static int emc_seq_update_timing(struct tegra_emc *emc)
{
u32 val;
int err;
writel_relaxed(EMC_TIMING_UPDATE, emc->regs + EMC_TIMING_CONTROL);
err = readl_relaxed_poll_timeout_atomic(emc->regs + EMC_STATUS, val,
!(val & EMC_STATUS_TIMING_UPDATE_STALLED),
1, 200);
if (err) {
dev_err(emc->dev, "failed to update timing: %d\n", err);
return err;
}
return 0;
}
static int emc_prepare_mc_clk_cfg(struct tegra_emc *emc, unsigned long rate)
{
struct tegra_mc *mc = emc->mc;
@ -582,8 +639,7 @@ static int emc_prepare_timing_change(struct tegra_emc *emc, unsigned long rate)
!(val & EMC_AUTO_CAL_STATUS_ACTIVE), 1, 300);
if (err) {
dev_err(emc->dev,
"failed to disable auto-cal: %d\n",
err);
"auto-cal finish timeout: %d\n", err);
return err;
}
@ -621,9 +677,6 @@ static int emc_prepare_timing_change(struct tegra_emc *emc, unsigned long rate)
writel_relaxed(val, emc->regs + EMC_MRS_WAIT_CNT);
}
/* disable interrupt since read access is prohibited after stalling */
disable_irq(emc->irq);
/* this read also completes the writes */
val = readl_relaxed(emc->regs + EMC_SEL_DPD_CTRL);
@ -739,20 +792,18 @@ static int emc_prepare_timing_change(struct tegra_emc *emc, unsigned long rate)
emc->regs + EMC_ZQ_CAL);
}
/* re-enable auto-refresh */
writel_relaxed(EMC_REFCTRL_ENABLE_ALL(dram_num),
emc->regs + EMC_REFCTRL);
/* flow control marker 3 */
writel_relaxed(0x1, emc->regs + EMC_UNSTALL_RW_AFTER_CLKCHANGE);
/*
* Read and discard an arbitrary MC register (Note: EMC registers
* can't be used) to ensure the register writes are completed.
*/
mc_readl(emc->mc, MC_EMEM_ARB_OVERRIDE);
reinit_completion(&emc->clk_handshake_complete);
/* interrupt can be re-enabled now */
enable_irq(emc->irq);
emc->bad_state = false;
emc->prepared = true;
emc->new_timing = timing;
return 0;
}
@ -760,52 +811,25 @@ static int emc_prepare_timing_change(struct tegra_emc *emc, unsigned long rate)
static int emc_complete_timing_change(struct tegra_emc *emc,
unsigned long rate)
{
struct emc_timing *timing = emc_find_timing(emc, rate);
unsigned long timeout;
int ret;
timeout = wait_for_completion_timeout(&emc->clk_handshake_complete,
msecs_to_jiffies(100));
if (timeout == 0) {
dev_err(emc->dev, "emc-car handshake failed\n");
emc->bad_state = true;
return -EIO;
}
/* restore auto-calibration */
if (emc->vref_cal_toggle)
writel_relaxed(timing->emc_auto_cal_interval,
emc->regs + EMC_AUTO_CAL_INTERVAL);
if (READ_ONCE(emc->bad_state))
return -EIO;
/* restore dynamic self-refresh */
if (timing->emc_cfg_dyn_self_ref) {
emc->emc_cfg |= EMC_CFG_DYN_SREF_ENABLE;
writel_relaxed(emc->emc_cfg, emc->regs + EMC_CFG);
}
/* set number of clocks to wait after each ZQ command */
if (emc->zcal_long)
writel_relaxed(timing->emc_zcal_cnt_long,
emc->regs + EMC_ZCAL_WAIT_CNT);
udelay(2);
/* update restored timing */
ret = emc_seq_update_timing(emc);
if (ret)
emc->bad_state = true;
/* restore early ACK */
mc_writel(emc->mc, emc->mc_override, MC_EMEM_ARB_OVERRIDE);
emc->prepared = false;
return ret;
return 0;
}
static int emc_unprepare_timing_change(struct tegra_emc *emc,
unsigned long rate)
{
if (emc->prepared && !emc->bad_state) {
if (!emc->bad_state) {
/* shouldn't ever happen in practice */
dev_err(emc->dev, "timing configuration can't be reverted\n");
emc->bad_state = true;
@ -823,7 +847,13 @@ static int emc_clk_change_notify(struct notifier_block *nb,
switch (msg) {
case PRE_RATE_CHANGE:
/*
* Disable interrupt since read accesses are prohibited after
* stalling.
*/
disable_irq(emc->irq);
err = emc_prepare_timing_change(emc, cnd->new_rate);
enable_irq(emc->irq);
break;
case ABORT_RATE_CHANGE:
@ -1083,6 +1113,171 @@ static long emc_round_rate(unsigned long rate,
return timing->rate;
}
/*
* debugfs interface
*
* The memory controller driver exposes some files in debugfs that can be used
* to control the EMC frequency. The top-level directory can be found here:
*
* /sys/kernel/debug/emc
*
* It contains the following files:
*
* - available_rates: This file contains a list of valid, space-separated
* EMC frequencies.
*
* - min_rate: Writing a value to this file sets the given frequency as the
* floor of the permitted range. If this is higher than the currently
* configured EMC frequency, this will cause the frequency to be
* increased so that it stays within the valid range.
*
* - max_rate: Similarily to the min_rate file, writing a value to this file
* sets the given frequency as the ceiling of the permitted range. If
* the value is lower than the currently configured EMC frequency, this
* will cause the frequency to be decreased so that it stays within the
* valid range.
*/
static bool tegra_emc_validate_rate(struct tegra_emc *emc, unsigned long rate)
{
unsigned int i;
for (i = 0; i < emc->num_timings; i++)
if (rate == emc->timings[i].rate)
return true;
return false;
}
static int tegra_emc_debug_available_rates_show(struct seq_file *s, void *data)
{
struct tegra_emc *emc = s->private;
const char *prefix = "";
unsigned int i;
for (i = 0; i < emc->num_timings; i++) {
seq_printf(s, "%s%lu", prefix, emc->timings[i].rate);
prefix = " ";
}
seq_puts(s, "\n");
return 0;
}
static int tegra_emc_debug_available_rates_open(struct inode *inode,
struct file *file)
{
return single_open(file, tegra_emc_debug_available_rates_show,
inode->i_private);
}
static const struct file_operations tegra_emc_debug_available_rates_fops = {
.open = tegra_emc_debug_available_rates_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int tegra_emc_debug_min_rate_get(void *data, u64 *rate)
{
struct tegra_emc *emc = data;
*rate = emc->debugfs.min_rate;
return 0;
}
static int tegra_emc_debug_min_rate_set(void *data, u64 rate)
{
struct tegra_emc *emc = data;
int err;
if (!tegra_emc_validate_rate(emc, rate))
return -EINVAL;
err = clk_set_min_rate(emc->clk, rate);
if (err < 0)
return err;
emc->debugfs.min_rate = rate;
return 0;
}
DEFINE_SIMPLE_ATTRIBUTE(tegra_emc_debug_min_rate_fops,
tegra_emc_debug_min_rate_get,
tegra_emc_debug_min_rate_set, "%llu\n");
static int tegra_emc_debug_max_rate_get(void *data, u64 *rate)
{
struct tegra_emc *emc = data;
*rate = emc->debugfs.max_rate;
return 0;
}
static int tegra_emc_debug_max_rate_set(void *data, u64 rate)
{
struct tegra_emc *emc = data;
int err;
if (!tegra_emc_validate_rate(emc, rate))
return -EINVAL;
err = clk_set_max_rate(emc->clk, rate);
if (err < 0)
return err;
emc->debugfs.max_rate = rate;
return 0;
}
DEFINE_SIMPLE_ATTRIBUTE(tegra_emc_debug_max_rate_fops,
tegra_emc_debug_max_rate_get,
tegra_emc_debug_max_rate_set, "%llu\n");
static void tegra_emc_debugfs_init(struct tegra_emc *emc)
{
struct device *dev = emc->dev;
unsigned int i;
int err;
emc->debugfs.min_rate = ULONG_MAX;
emc->debugfs.max_rate = 0;
for (i = 0; i < emc->num_timings; i++) {
if (emc->timings[i].rate < emc->debugfs.min_rate)
emc->debugfs.min_rate = emc->timings[i].rate;
if (emc->timings[i].rate > emc->debugfs.max_rate)
emc->debugfs.max_rate = emc->timings[i].rate;
}
err = clk_set_rate_range(emc->clk, emc->debugfs.min_rate,
emc->debugfs.max_rate);
if (err < 0) {
dev_err(dev, "failed to set rate range [%lu-%lu] for %pC\n",
emc->debugfs.min_rate, emc->debugfs.max_rate,
emc->clk);
}
emc->debugfs.root = debugfs_create_dir("emc", NULL);
if (!emc->debugfs.root) {
dev_err(emc->dev, "failed to create debugfs directory\n");
return;
}
debugfs_create_file("available_rates", S_IRUGO, emc->debugfs.root,
emc, &tegra_emc_debug_available_rates_fops);
debugfs_create_file("min_rate", S_IRUGO | S_IWUSR, emc->debugfs.root,
emc, &tegra_emc_debug_min_rate_fops);
debugfs_create_file("max_rate", S_IRUGO | S_IWUSR, emc->debugfs.root,
emc, &tegra_emc_debug_max_rate_fops);
}
static int tegra_emc_probe(struct platform_device *pdev)
{
struct platform_device *mc;
@ -1169,6 +1364,7 @@ static int tegra_emc_probe(struct platform_device *pdev)
}
platform_set_drvdata(pdev, emc);
tegra_emc_debugfs_init(emc);
return 0;
@ -1181,13 +1377,17 @@ unset_cb:
static int tegra_emc_suspend(struct device *dev)
{
struct tegra_emc *emc = dev_get_drvdata(dev);
int err;
/*
* Suspending in a bad state will hang machine. The "prepared" var
* shall be always false here unless it's a kernel bug that caused
* suspending in a wrong order.
*/
if (WARN_ON(emc->prepared) || emc->bad_state)
/* take exclusive control over the clock's rate */
err = clk_rate_exclusive_get(emc->clk);
if (err) {
dev_err(emc->dev, "failed to acquire clk: %d\n", err);
return err;
}
/* suspending in a bad state will hang machine */
if (WARN(emc->bad_state, "hardware in a bad state\n"))
return -EINVAL;
emc->bad_state = true;
@ -1202,6 +1402,8 @@ static int tegra_emc_resume(struct device *dev)
emc_setup_hw(emc);
emc->bad_state = false;
clk_rate_exclusive_put(emc->clk);
return 0;
}