Merge tag 'memory-controller-drv-tegra-5.14-2' of https://git.kernel.org/pub/scm/linux/kernel/git/krzk/linux-mem-ctrl into arm/drivers

Memory controller drivers for v5.14 - Tegra SoC, part two

Second set of changes for Tegra SoC memory controller drivers,
containing patchset from Thierry Reding:

"The goal here is to avoid early identity mappings altogether and instead
postpone the need for the identity mappings to when devices are attached
to the SMMU. This works by making the SMMU driver coordinate with the
memory controller driver on when to start enforcing SMMU translations.
This makes Tegra behave in a more standard way and pushes the code to
deal with the Tegra-specific programming into the NVIDIA SMMU
implementation."

This pulls a dependency from Will Deacon (ARM SMMU driver) and contains
further ARM SMMU driver patches to resolve complex dependencies between
different patchsets.  The pull from Will contains only one patch
("Implement ->probe_finalize()").  Further work in Will's tree might
depend on this patch, therefore patch was applied there.

On the other hand, this ("Implement ->probe_finalize()") patch is also a
dependency for ARM SMMU driver changes for Tegra.  These changes,
bringing seamless transition from the firmware framebuffer to the OS
framebuffer, depend on earlier Tegra memory controller driver patches.

* tag 'memory-controller-drv-tegra-5.14-2' of https://git.kernel.org/pub/scm/linux/kernel/git/krzk/linux-mem-ctrl: (37 commits)
  iommu/arm-smmu: Use Tegra implementation on Tegra186
  iommu/arm-smmu: tegra: Implement SID override programming
  iommu/arm-smmu: tegra: Detect number of instances at runtime
  dt-bindings: arm-smmu: Add Tegra186 compatible string
  memory: tegra: Delete dead debugfs checking code
  iommu/arm-smmu: Implement ->probe_finalize()
  memory: tegra: Implement SID override programming
  memory: tegra: Split Tegra194 data into separate file
  memory: tegra: Add memory client IDs to tables
  memory: tegra: Unify drivers
  memory: tegra: Only initialize reset controller if available
  memory: tegra: Make IRQ support opitonal
  memory: tegra: Parameterize interrupt handler
  memory: tegra: Extract setup code into callback
  memory: tegra: Make per-SoC setup more generic
  memory: tegra: Push suspend/resume into SoC drivers
  memory: tegra: Introduce struct tegra_mc_ops
  memory: tegra: Unify struct tegra_mc across SoC generations
  memory: tegra: Consolidate register fields
  memory: tegra30-emc: Use devm_tegra_core_dev_init_opp_table()
  ...

Link: https://lore.kernel.org/r/20210614195200.21657-1-krzysztof.kozlowski@canonical.com
Signed-off-by: Olof Johansson <olof@lixom.net>

4 files changed, 245 insertions, 7 deletions

diff --git a/drivers/soc/tegra/common.c b/drivers/soc/tegra/common.c
index 3dc54f59cafe..cd33e99249c3 100644
--- a/drivers/soc/tegra/common.c
+++ b/drivers/soc/tegra/common.c
@@ -3,9 +3,16 @@
  * Copyright (C) 2014 NVIDIA CORPORATION.  All rights reserved.
  */
 
+#define dev_fmt(fmt)	"tegra-soc: " fmt
+
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/export.h>
 #include <linux/of.h>
+#include <linux/pm_opp.h>
 
 #include <soc/tegra/common.h>
+#include <soc/tegra/fuse.h>
 
 static const struct of_device_id tegra_machine_match[] = {
 	{ .compatible = "nvidia,tegra20", },
@@ -31,3 +38,93 @@ bool soc_is_tegra(void)
 
 	return match != NULL;
 }
+
+static int tegra_core_dev_init_opp_state(struct device *dev)
+{
+	unsigned long rate;
+	struct clk *clk;
+	int err;
+
+	clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(clk)) {
+		dev_err(dev, "failed to get clk: %pe\n", clk);
+		return PTR_ERR(clk);
+	}
+
+	rate = clk_get_rate(clk);
+	if (!rate) {
+		dev_err(dev, "failed to get clk rate\n");
+		return -EINVAL;
+	}
+
+	/* first dummy rate-setting initializes voltage vote */
+	err = dev_pm_opp_set_rate(dev, rate);
+	if (err) {
+		dev_err(dev, "failed to initialize OPP clock: %d\n", err);
+		return err;
+	}
+
+	return 0;
+}
+
+/**
+ * devm_tegra_core_dev_init_opp_table() - initialize OPP table
+ * @dev: device for which OPP table is initialized
+ * @params: pointer to the OPP table configuration
+ *
+ * This function will initialize OPP table and sync OPP state of a Tegra SoC
+ * core device.
+ *
+ * Return: 0 on success or errorno.
+ */
+int devm_tegra_core_dev_init_opp_table(struct device *dev,
+				       struct tegra_core_opp_params *params)
+{
+	u32 hw_version;
+	int err;
+
+	err = devm_pm_opp_set_clkname(dev, NULL);
+	if (err) {
+		dev_err(dev, "failed to set OPP clk: %d\n", err);
+		return err;
+	}
+
+	/* Tegra114+ doesn't support OPP yet */
+	if (!of_machine_is_compatible("nvidia,tegra20") &&
+	    !of_machine_is_compatible("nvidia,tegra30"))
+		return -ENODEV;
+
+	if (of_machine_is_compatible("nvidia,tegra20"))
+		hw_version = BIT(tegra_sku_info.soc_process_id);
+	else
+		hw_version = BIT(tegra_sku_info.soc_speedo_id);
+
+	err = devm_pm_opp_set_supported_hw(dev, &hw_version, 1);
+	if (err) {
+		dev_err(dev, "failed to set OPP supported HW: %d\n", err);
+		return err;
+	}
+
+	/*
+	 * Older device-trees have an empty OPP table, we will get
+	 * -ENODEV from devm_pm_opp_of_add_table() in this case.
+	 */
+	err = devm_pm_opp_of_add_table(dev);
+	if (err) {
+		if (err == -ENODEV)
+			dev_err_once(dev, "OPP table not found, please update device-tree\n");
+		else
+			dev_err(dev, "failed to add OPP table: %d\n", err);
+
+		return err;
+	}
+
+	if (params->init_state) {
+		err = tegra_core_dev_init_opp_state(dev);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(devm_tegra_core_dev_init_opp_table);
diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c
index 8e3b78bb2ac2..4a582eae82ef 100644
--- a/drivers/soc/tegra/pmc.c
+++ b/drivers/soc/tegra/pmc.c
@@ -743,11 +743,6 @@ out:
 	return err;
 }
 
-int __weak tegra210_clk_handle_mbist_war(unsigned int id)
-{
-	return 0;
-}
-
 static int tegra_powergate_power_up(struct tegra_powergate *pg,
 				    bool disable_clocks)
 {
diff --git a/drivers/soc/tegra/regulators-tegra20.c b/drivers/soc/tegra/regulators-tegra20.c
index 367a71a3cd10..3479be5ee494 100644
--- a/drivers/soc/tegra/regulators-tegra20.c
+++ b/drivers/soc/tegra/regulators-tegra20.c
@@ -12,6 +12,7 @@
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/of.h>
+#include <linux/reboot.h>
 #include <linux/regulator/coupler.h>
 #include <linux/regulator/driver.h>
 #include <linux/regulator/machine.h>
@@ -21,7 +22,10 @@ struct tegra_regulator_coupler {
 	struct regulator_dev *core_rdev;
 	struct regulator_dev *cpu_rdev;
 	struct regulator_dev *rtc_rdev;
-	int core_min_uV;
+	struct notifier_block reboot_notifier;
+	int core_min_uV, cpu_min_uV;
+	bool sys_reboot_mode_req;
+	bool sys_reboot_mode;
 };
 
 static inline struct tegra_regulator_coupler *
@@ -242,6 +246,10 @@ static int tegra20_cpu_voltage_update(struct tegra_regulator_coupler *tegra,
 	if (cpu_uV < 0)
 		return cpu_uV;
 
+	/* store boot voltage level */
+	if (!tegra->cpu_min_uV)
+		tegra->cpu_min_uV = cpu_uV;
+
 	/*
 	 * CPU's regulator may not have any consumers, hence the voltage
 	 * must not be changed in that case because CPU simply won't
@@ -250,6 +258,10 @@ static int tegra20_cpu_voltage_update(struct tegra_regulator_coupler *tegra,
 	if (!cpu_min_uV_consumers)
 		cpu_min_uV = cpu_uV;
 
+	/* restore boot voltage level */
+	if (tegra->sys_reboot_mode)
+		cpu_min_uV = max(cpu_min_uV, tegra->cpu_min_uV);
+
 	if (cpu_min_uV > cpu_uV) {
 		err = tegra20_core_rtc_update(tegra, core_rdev, rtc_rdev,
 					      cpu_uV, cpu_min_uV);
@@ -290,6 +302,8 @@ static int tegra20_regulator_balance_voltage(struct regulator_coupler *coupler,
 		return -EINVAL;
 	}
 
+	tegra->sys_reboot_mode = READ_ONCE(tegra->sys_reboot_mode_req);
+
 	if (rdev == cpu_rdev)
 		return tegra20_cpu_voltage_update(tegra, cpu_rdev,
 						  core_rdev, rtc_rdev);
@@ -303,6 +317,51 @@ static int tegra20_regulator_balance_voltage(struct regulator_coupler *coupler,
 	return -EPERM;
 }
 
+static int tegra20_regulator_prepare_reboot(struct tegra_regulator_coupler *tegra,
+					    bool sys_reboot_mode)
+{
+	int err;
+
+	if (!tegra->core_rdev || !tegra->rtc_rdev || !tegra->cpu_rdev)
+		return 0;
+
+	WRITE_ONCE(tegra->sys_reboot_mode_req, true);
+
+	/*
+	 * Some devices use CPU soft-reboot method and in this case we
+	 * should ensure that voltages are sane for the reboot by restoring
+	 * the minimum boot levels.
+	 */
+	err = regulator_sync_voltage_rdev(tegra->cpu_rdev);
+	if (err)
+		return err;
+
+	err = regulator_sync_voltage_rdev(tegra->core_rdev);
+	if (err)
+		return err;
+
+	WRITE_ONCE(tegra->sys_reboot_mode_req, sys_reboot_mode);
+
+	return 0;
+}
+
+static int tegra20_regulator_reboot(struct notifier_block *notifier,
+				    unsigned long event, void *cmd)
+{
+	struct tegra_regulator_coupler *tegra;
+	int ret;
+
+	if (event != SYS_RESTART)
+		return NOTIFY_DONE;
+
+	tegra = container_of(notifier, struct tegra_regulator_coupler,
+			     reboot_notifier);
+
+	ret = tegra20_regulator_prepare_reboot(tegra, true);
+
+	return notifier_from_errno(ret);
+}
+
 static int tegra20_regulator_attach(struct regulator_coupler *coupler,
 				    struct regulator_dev *rdev)
 {
@@ -335,6 +394,14 @@ static int tegra20_regulator_detach(struct regulator_coupler *coupler,
 {
 	struct tegra_regulator_coupler *tegra = to_tegra_coupler(coupler);
 
+	/*
+	 * We don't expect regulators to be decoupled during reboot,
+	 * this may race with the reboot handler and shouldn't ever
+	 * happen in practice.
+	 */
+	if (WARN_ON_ONCE(system_state > SYSTEM_RUNNING))
+		return -EPERM;
+
 	if (tegra->core_rdev == rdev) {
 		tegra->core_rdev = NULL;
 		return 0;
@@ -359,13 +426,19 @@ static struct tegra_regulator_coupler tegra20_coupler = {
 		.detach_regulator = tegra20_regulator_detach,
 		.balance_voltage = tegra20_regulator_balance_voltage,
 	},
+	.reboot_notifier.notifier_call = tegra20_regulator_reboot,
 };
 
 static int __init tegra_regulator_coupler_init(void)
 {
+	int err;
+
 	if (!of_machine_is_compatible("nvidia,tegra20"))
 		return 0;
 
+	err = register_reboot_notifier(&tegra20_coupler.reboot_notifier);
+	WARN_ON(err);
+
 	return regulator_coupler_register(&tegra20_coupler.coupler);
 }
 arch_initcall(tegra_regulator_coupler_init);
diff --git a/drivers/soc/tegra/regulators-tegra30.c b/drivers/soc/tegra/regulators-tegra30.c
index 0e776b20f625..18fe53d0a870 100644
--- a/drivers/soc/tegra/regulators-tegra30.c
+++ b/drivers/soc/tegra/regulators-tegra30.c
@@ -12,6 +12,7 @@
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/of.h>
+#include <linux/reboot.h>
 #include <linux/regulator/coupler.h>
 #include <linux/regulator/driver.h>
 #include <linux/regulator/machine.h>
@@ -22,7 +23,10 @@ struct tegra_regulator_coupler {
 	struct regulator_coupler coupler;
 	struct regulator_dev *core_rdev;
 	struct regulator_dev *cpu_rdev;
-	int core_min_uV;
+	struct notifier_block reboot_notifier;
+	int core_min_uV, cpu_min_uV;
+	bool sys_reboot_mode_req;
+	bool sys_reboot_mode;
 };
 
 static inline struct tegra_regulator_coupler *
@@ -172,6 +176,10 @@ static int tegra30_voltage_update(struct tegra_regulator_coupler *tegra,
 	if (cpu_uV < 0)
 		return cpu_uV;
 
+	/* store boot voltage level */
+	if (!tegra->cpu_min_uV)
+		tegra->cpu_min_uV = cpu_uV;
+
 	/*
 	 * CPU's regulator may not have any consumers, hence the voltage
 	 * must not be changed in that case because CPU simply won't
@@ -195,6 +203,10 @@ static int tegra30_voltage_update(struct tegra_regulator_coupler *tegra,
 	if (err)
 		return err;
 
+	/* restore boot voltage level */
+	if (tegra->sys_reboot_mode)
+		cpu_min_uV = max(cpu_min_uV, tegra->cpu_min_uV);
+
 	if (core_min_limited_uV > core_uV) {
 		pr_err("core voltage constraint violated: %d %d %d\n",
 		       core_uV, core_min_limited_uV, cpu_uV);
@@ -263,9 +275,56 @@ static int tegra30_regulator_balance_voltage(struct regulator_coupler *coupler,
 		return -EINVAL;
 	}
 
+	tegra->sys_reboot_mode = READ_ONCE(tegra->sys_reboot_mode_req);
+
 	return tegra30_voltage_update(tegra, cpu_rdev, core_rdev);
 }
 
+static int tegra30_regulator_prepare_reboot(struct tegra_regulator_coupler *tegra,
+					    bool sys_reboot_mode)
+{
+	int err;
+
+	if (!tegra->core_rdev || !tegra->cpu_rdev)
+		return 0;
+
+	WRITE_ONCE(tegra->sys_reboot_mode_req, true);
+
+	/*
+	 * Some devices use CPU soft-reboot method and in this case we
+	 * should ensure that voltages are sane for the reboot by restoring
+	 * the minimum boot levels.
+	 */
+	err = regulator_sync_voltage_rdev(tegra->cpu_rdev);
+	if (err)
+		return err;
+
+	err = regulator_sync_voltage_rdev(tegra->core_rdev);
+	if (err)
+		return err;
+
+	WRITE_ONCE(tegra->sys_reboot_mode_req, sys_reboot_mode);
+
+	return 0;
+}
+
+static int tegra30_regulator_reboot(struct notifier_block *notifier,
+				    unsigned long event, void *cmd)
+{
+	struct tegra_regulator_coupler *tegra;
+	int ret;
+
+	if (event != SYS_RESTART)
+		return NOTIFY_DONE;
+
+	tegra = container_of(notifier, struct tegra_regulator_coupler,
+			     reboot_notifier);
+
+	ret = tegra30_regulator_prepare_reboot(tegra, true);
+
+	return notifier_from_errno(ret);
+}
+
 static int tegra30_regulator_attach(struct regulator_coupler *coupler,
 				    struct regulator_dev *rdev)
 {
@@ -292,6 +351,14 @@ static int tegra30_regulator_detach(struct regulator_coupler *coupler,
 {
 	struct tegra_regulator_coupler *tegra = to_tegra_coupler(coupler);
 
+	/*
+	 * We don't expect regulators to be decoupled during reboot,
+	 * this may race with the reboot handler and shouldn't ever
+	 * happen in practice.
+	 */
+	if (WARN_ON_ONCE(system_state > SYSTEM_RUNNING))
+		return -EPERM;
+
 	if (tegra->core_rdev == rdev) {
 		tegra->core_rdev = NULL;
 		return 0;
@@ -311,13 +378,19 @@ static struct tegra_regulator_coupler tegra30_coupler = {
 		.detach_regulator = tegra30_regulator_detach,
 		.balance_voltage = tegra30_regulator_balance_voltage,
 	},
+	.reboot_notifier.notifier_call = tegra30_regulator_reboot,
 };
 
 static int __init tegra_regulator_coupler_init(void)
 {
+	int err;
+
 	if (!of_machine_is_compatible("nvidia,tegra30"))
 		return 0;
 
+	err = register_reboot_notifier(&tegra30_coupler.reboot_notifier);
+	WARN_ON(err);
+
 	return regulator_coupler_register(&tegra30_coupler.coupler);
 }
 arch_initcall(tegra_regulator_coupler_init);