Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 421 insertions, 0 deletions

diff --git a/drivers/memory/tegra/tegra186-emc.c b/drivers/memory/tegra/tegra186-emc.c
new file mode 100644
index 0000000000..4007f4e16d
--- /dev/null
+++ b/drivers/memory/tegra/tegra186-emc.c
@@ -0,0 +1,421 @@
+// 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/of_platform.h>
+#include <linux/platform_device.h>
+
+#include <soc/tegra/bpmp.h>
+#include "mc.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;
+
+	struct icc_provider provider;
+};
+
+static inline struct tegra186_emc *to_tegra186_emc(struct icc_provider *provider)
+{
+	return container_of(provider, struct tegra186_emc, provider);
+}
+
+/*
+ * 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;
+}
+DEFINE_SHOW_ATTRIBUTE(tegra186_emc_debug_available_rates);
+
+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_DEBUGFS_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_DEBUGFS_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_get_emc_dvfs_latency(struct tegra186_emc *emc)
+{
+	struct mrq_emc_dvfs_latency_response response;
+	struct tegra_bpmp_message msg;
+	unsigned int i;
+	int err;
+
+	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(emc->dev, "failed to EMC DVFS pairs: %d\n", err);
+		return err;
+	}
+	if (msg.rx.ret < 0) {
+		dev_err(emc->dev, "EMC DVFS MRQ failed: %d (BPMP error code)\n", msg.rx.ret);
+		return -EINVAL;
+	}
+
+	emc->debugfs.min_rate = ULONG_MAX;
+	emc->debugfs.max_rate = 0;
+
+	emc->num_dvfs = response.num_pairs;
+
+	emc->dvfs = devm_kmalloc_array(emc->dev, emc->num_dvfs, sizeof(*emc->dvfs), GFP_KERNEL);
+	if (!emc->dvfs)
+		return -ENOMEM;
+
+	dev_dbg(emc->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(emc->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(emc->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);
+	debugfs_create_file("available_rates", 0444, emc->debugfs.root, emc,
+			    &tegra186_emc_debug_available_rates_fops);
+	debugfs_create_file("min_rate", 0644, emc->debugfs.root, emc,
+			    &tegra186_emc_debug_min_rate_fops);
+	debugfs_create_file("max_rate", 0644, emc->debugfs.root, emc,
+			    &tegra186_emc_debug_max_rate_fops);
+
+	return 0;
+}
+
+/*
+ * tegra_emc_icc_set_bw() - Set BW api for EMC provider
+ * @src: ICC node for External Memory Controller (EMC)
+ * @dst: ICC node for External Memory (DRAM)
+ *
+ * Do nothing here as info to BPMP-FW is now passed in the BW set function
+ * of the MC driver. BPMP-FW sets the final Freq based on the passed values.
+ */
+static int tegra_emc_icc_set_bw(struct icc_node *src, struct icc_node *dst)
+{
+	return 0;
+}
+
+static struct icc_node *
+tegra_emc_of_icc_xlate(struct of_phandle_args *spec, void *data)
+{
+	struct icc_provider *provider = data;
+	struct icc_node *node;
+
+	/* External Memory is the only possible ICC route */
+	list_for_each_entry(node, &provider->nodes, node_list) {
+		if (node->id != TEGRA_ICC_EMEM)
+			continue;
+
+		return node;
+	}
+
+	return ERR_PTR(-EPROBE_DEFER);
+}
+
+static int tegra_emc_icc_get_init_bw(struct icc_node *node, u32 *avg, u32 *peak)
+{
+	*avg = 0;
+	*peak = 0;
+
+	return 0;
+}
+
+static int tegra_emc_interconnect_init(struct tegra186_emc *emc)
+{
+	struct tegra_mc *mc = dev_get_drvdata(emc->dev->parent);
+	const struct tegra_mc_soc *soc = mc->soc;
+	struct icc_node *node;
+	int err;
+
+	emc->provider.dev = emc->dev;
+	emc->provider.set = tegra_emc_icc_set_bw;
+	emc->provider.data = &emc->provider;
+	emc->provider.aggregate = soc->icc_ops->aggregate;
+	emc->provider.xlate = tegra_emc_of_icc_xlate;
+	emc->provider.get_bw = tegra_emc_icc_get_init_bw;
+
+	icc_provider_init(&emc->provider);
+
+	/* create External Memory Controller node */
+	node = icc_node_create(TEGRA_ICC_EMC);
+	if (IS_ERR(node)) {
+		err = PTR_ERR(node);
+		goto err_msg;
+	}
+
+	node->name = "External Memory Controller";
+	icc_node_add(node, &emc->provider);
+
+	/* link External Memory Controller to External Memory (DRAM) */
+	err = icc_link_create(node, TEGRA_ICC_EMEM);
+	if (err)
+		goto remove_nodes;
+
+	/* create External Memory node */
+	node = icc_node_create(TEGRA_ICC_EMEM);
+	if (IS_ERR(node)) {
+		err = PTR_ERR(node);
+		goto remove_nodes;
+	}
+
+	node->name = "External Memory (DRAM)";
+	icc_node_add(node, &emc->provider);
+
+	err = icc_provider_register(&emc->provider);
+	if (err)
+		goto remove_nodes;
+
+	return 0;
+
+remove_nodes:
+	icc_nodes_remove(&emc->provider);
+err_msg:
+	dev_err(emc->dev, "failed to initialize ICC: %d\n", err);
+
+	return err;
+}
+
+static int tegra186_emc_probe(struct platform_device *pdev)
+{
+	struct tegra_mc *mc = dev_get_drvdata(pdev->dev.parent);
+	struct tegra186_emc *emc;
+	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))
+		return dev_err_probe(&pdev->dev, PTR_ERR(emc->bpmp), "failed to get BPMP\n");
+
+	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);
+		goto put_bpmp;
+	}
+
+	platform_set_drvdata(pdev, emc);
+	emc->dev = &pdev->dev;
+
+	if (tegra_bpmp_mrq_is_supported(emc->bpmp, MRQ_EMC_DVFS_LATENCY)) {
+		err = tegra186_emc_get_emc_dvfs_latency(emc);
+		if (err)
+			goto put_bpmp;
+	}
+
+	if (mc && mc->soc->icc_ops) {
+		if (tegra_bpmp_mrq_is_supported(emc->bpmp, MRQ_BWMGR_INT)) {
+			mc->bwmgr_mrq_supported = true;
+
+			/*
+			 * MC driver probe can't get BPMP reference as it gets probed
+			 * earlier than BPMP. So, save the BPMP ref got from the EMC
+			 * DT node in the mc->bpmp and use it in MC's icc_set hook.
+			 */
+			mc->bpmp = emc->bpmp;
+			barrier();
+		}
+
+		/*
+		 * Initialize the ICC even if BPMP-FW doesn't support 'MRQ_BWMGR_INT'.
+		 * Use the flag 'mc->bwmgr_mrq_supported' within MC driver and return
+		 * EINVAL instead of passing the request to BPMP-FW later when the BW
+		 * request is made by client with 'icc_set_bw()' call.
+		 */
+		err = tegra_emc_interconnect_init(emc);
+		if (err) {
+			mc->bpmp = NULL;
+			goto put_bpmp;
+		}
+	}
+
+	return 0;
+
+put_bpmp:
+	tegra_bpmp_put(emc->bpmp);
+	return err;
+}
+
+static int tegra186_emc_remove(struct platform_device *pdev)
+{
+	struct tegra_mc *mc = dev_get_drvdata(pdev->dev.parent);
+	struct tegra186_emc *emc = platform_get_drvdata(pdev);
+
+	debugfs_remove_recursive(emc->debugfs.root);
+
+	mc->bpmp = NULL;
+	tegra_bpmp_put(emc->bpmp);
+
+	return 0;
+}
+
+static const struct of_device_id tegra186_emc_of_match[] = {
+#if defined(CONFIG_ARCH_TEGRA_186_SOC)
+	{ .compatible = "nvidia,tegra186-emc" },
+#endif
+#if defined(CONFIG_ARCH_TEGRA_194_SOC)
+	{ .compatible = "nvidia,tegra194-emc" },
+#endif
+#if defined(CONFIG_ARCH_TEGRA_234_SOC)
+	{ .compatible = "nvidia,tegra234-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,
+		.sync_state = icc_sync_state,
+	},
+	.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");