@@ -13,4 +13,4 @@ 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
new file mode 100644
@@ -0,0 +1,288 @@
+// 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[] = {
+ { .compatible = "nvidia,tegra186-emc" },
+ { /* 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");
@@ -590,12 +590,30 @@ static int tegra186_mc_probe(struct platform_device *pdev)
mc->dev = &pdev->dev;
+ err = of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
+ if (err < 0)
+ goto unregister;
+
platform_set_drvdata(pdev, mc);
tegra186_mc_program_sid(mc);
+ return 0;
+
+unregister:
+ memory_controller_unregister(&mc->base);
return err;
}
+static int tegra186_mc_remove(struct platform_device *pdev)
+{
+ struct tegra186_mc *mc = platform_get_drvdata(pdev);
+
+ of_platform_depopulate(mc->dev);
+ memory_controller_unregister(&mc->base);
+
+ return 0;
+}
+
static const struct of_device_id tegra186_mc_of_match[] = {
{ .compatible = "nvidia,tegra186-mc", .data = &tegra186_mc_soc },
{ /* sentinel */ }
@@ -627,8 +645,8 @@ static struct platform_driver tegra186_mc_driver = {
.pm = &tegra186_mc_pm_ops,
.suppress_bind_attrs = true,
},
- .prevent_deferred_probe = true,
.probe = tegra186_mc_probe,
+ .remove = tegra186_mc_remove,
};
module_platform_driver(tegra186_mc_driver);