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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /drivers/devfreq/mtk-cci-devfreq.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'drivers/devfreq/mtk-cci-devfreq.c')
-rw-r--r--drivers/devfreq/mtk-cci-devfreq.c444
1 files changed, 444 insertions, 0 deletions
diff --git a/drivers/devfreq/mtk-cci-devfreq.c b/drivers/devfreq/mtk-cci-devfreq.c
new file mode 100644
index 000000000..4c22be728
--- /dev/null
+++ b/drivers/devfreq/mtk-cci-devfreq.c
@@ -0,0 +1,444 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2022 MediaTek Inc.
+ */
+
+#include <linux/clk.h>
+#include <linux/devfreq.h>
+#include <linux/minmax.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_opp.h>
+#include <linux/regulator/consumer.h>
+
+struct mtk_ccifreq_platform_data {
+ int min_volt_shift;
+ int max_volt_shift;
+ int proc_max_volt;
+ int sram_min_volt;
+ int sram_max_volt;
+};
+
+struct mtk_ccifreq_drv {
+ struct device *dev;
+ struct devfreq *devfreq;
+ struct regulator *proc_reg;
+ struct regulator *sram_reg;
+ struct clk *cci_clk;
+ struct clk *inter_clk;
+ int inter_voltage;
+ unsigned long pre_freq;
+ /* Avoid race condition for regulators between notify and policy */
+ struct mutex reg_lock;
+ struct notifier_block opp_nb;
+ const struct mtk_ccifreq_platform_data *soc_data;
+ int vtrack_max;
+};
+
+static int mtk_ccifreq_set_voltage(struct mtk_ccifreq_drv *drv, int new_voltage)
+{
+ const struct mtk_ccifreq_platform_data *soc_data = drv->soc_data;
+ struct device *dev = drv->dev;
+ int pre_voltage, pre_vsram, new_vsram, vsram, voltage, ret;
+ int retry_max = drv->vtrack_max;
+
+ if (!drv->sram_reg) {
+ ret = regulator_set_voltage(drv->proc_reg, new_voltage,
+ drv->soc_data->proc_max_volt);
+ return ret;
+ }
+
+ pre_voltage = regulator_get_voltage(drv->proc_reg);
+ if (pre_voltage < 0) {
+ dev_err(dev, "invalid vproc value: %d\n", pre_voltage);
+ return pre_voltage;
+ }
+
+ pre_vsram = regulator_get_voltage(drv->sram_reg);
+ if (pre_vsram < 0) {
+ dev_err(dev, "invalid vsram value: %d\n", pre_vsram);
+ return pre_vsram;
+ }
+
+ new_vsram = clamp(new_voltage + soc_data->min_volt_shift,
+ soc_data->sram_min_volt, soc_data->sram_max_volt);
+
+ do {
+ if (pre_voltage <= new_voltage) {
+ vsram = clamp(pre_voltage + soc_data->max_volt_shift,
+ soc_data->sram_min_volt, new_vsram);
+ ret = regulator_set_voltage(drv->sram_reg, vsram,
+ soc_data->sram_max_volt);
+ if (ret)
+ return ret;
+
+ if (vsram == soc_data->sram_max_volt ||
+ new_vsram == soc_data->sram_min_volt)
+ voltage = new_voltage;
+ else
+ voltage = vsram - soc_data->min_volt_shift;
+
+ ret = regulator_set_voltage(drv->proc_reg, voltage,
+ soc_data->proc_max_volt);
+ if (ret) {
+ regulator_set_voltage(drv->sram_reg, pre_vsram,
+ soc_data->sram_max_volt);
+ return ret;
+ }
+ } else {
+ voltage = max(new_voltage,
+ pre_vsram - soc_data->max_volt_shift);
+ ret = regulator_set_voltage(drv->proc_reg, voltage,
+ soc_data->proc_max_volt);
+ if (ret)
+ return ret;
+
+ if (voltage == new_voltage)
+ vsram = new_vsram;
+ else
+ vsram = max(new_vsram,
+ voltage + soc_data->min_volt_shift);
+
+ ret = regulator_set_voltage(drv->sram_reg, vsram,
+ soc_data->sram_max_volt);
+ if (ret) {
+ regulator_set_voltage(drv->proc_reg, pre_voltage,
+ soc_data->proc_max_volt);
+ return ret;
+ }
+ }
+
+ pre_voltage = voltage;
+ pre_vsram = vsram;
+
+ if (--retry_max < 0) {
+ dev_err(dev,
+ "over loop count, failed to set voltage\n");
+ return -EINVAL;
+ }
+ } while (voltage != new_voltage || vsram != new_vsram);
+
+ return 0;
+}
+
+static int mtk_ccifreq_target(struct device *dev, unsigned long *freq,
+ u32 flags)
+{
+ struct mtk_ccifreq_drv *drv = dev_get_drvdata(dev);
+ struct clk *cci_pll;
+ struct dev_pm_opp *opp;
+ unsigned long opp_rate;
+ int voltage, pre_voltage, inter_voltage, target_voltage, ret;
+
+ if (!drv)
+ return -EINVAL;
+
+ if (drv->pre_freq == *freq)
+ return 0;
+
+ mutex_lock(&drv->reg_lock);
+
+ inter_voltage = drv->inter_voltage;
+ cci_pll = clk_get_parent(drv->cci_clk);
+
+ opp_rate = *freq;
+ opp = devfreq_recommended_opp(dev, &opp_rate, 1);
+ if (IS_ERR(opp)) {
+ dev_err(dev, "failed to find opp for freq: %ld\n", opp_rate);
+ ret = PTR_ERR(opp);
+ goto out_unlock;
+ }
+
+ voltage = dev_pm_opp_get_voltage(opp);
+ dev_pm_opp_put(opp);
+
+ pre_voltage = regulator_get_voltage(drv->proc_reg);
+ if (pre_voltage < 0) {
+ dev_err(dev, "invalid vproc value: %d\n", pre_voltage);
+ ret = pre_voltage;
+ goto out_unlock;
+ }
+
+ /* scale up: set voltage first then freq. */
+ target_voltage = max(inter_voltage, voltage);
+ if (pre_voltage <= target_voltage) {
+ ret = mtk_ccifreq_set_voltage(drv, target_voltage);
+ if (ret) {
+ dev_err(dev, "failed to scale up voltage\n");
+ goto out_restore_voltage;
+ }
+ }
+
+ /* switch the cci clock to intermediate clock source. */
+ ret = clk_set_parent(drv->cci_clk, drv->inter_clk);
+ if (ret) {
+ dev_err(dev, "failed to re-parent cci clock\n");
+ goto out_restore_voltage;
+ }
+
+ /* set the original clock to target rate. */
+ ret = clk_set_rate(cci_pll, *freq);
+ if (ret) {
+ dev_err(dev, "failed to set cci pll rate: %d\n", ret);
+ clk_set_parent(drv->cci_clk, cci_pll);
+ goto out_restore_voltage;
+ }
+
+ /* switch the cci clock back to the original clock source. */
+ ret = clk_set_parent(drv->cci_clk, cci_pll);
+ if (ret) {
+ dev_err(dev, "failed to re-parent cci clock\n");
+ mtk_ccifreq_set_voltage(drv, inter_voltage);
+ goto out_unlock;
+ }
+
+ /*
+ * If the new voltage is lower than the intermediate voltage or the
+ * original voltage, scale down to the new voltage.
+ */
+ if (voltage < inter_voltage || voltage < pre_voltage) {
+ ret = mtk_ccifreq_set_voltage(drv, voltage);
+ if (ret) {
+ dev_err(dev, "failed to scale down voltage\n");
+ goto out_unlock;
+ }
+ }
+
+ drv->pre_freq = *freq;
+ mutex_unlock(&drv->reg_lock);
+
+ return 0;
+
+out_restore_voltage:
+ mtk_ccifreq_set_voltage(drv, pre_voltage);
+
+out_unlock:
+ mutex_unlock(&drv->reg_lock);
+ return ret;
+}
+
+static int mtk_ccifreq_opp_notifier(struct notifier_block *nb,
+ unsigned long event, void *data)
+{
+ struct dev_pm_opp *opp = data;
+ struct mtk_ccifreq_drv *drv;
+ unsigned long freq, volt;
+
+ drv = container_of(nb, struct mtk_ccifreq_drv, opp_nb);
+
+ if (event == OPP_EVENT_ADJUST_VOLTAGE) {
+ mutex_lock(&drv->reg_lock);
+ freq = dev_pm_opp_get_freq(opp);
+
+ /* current opp item is changed */
+ if (freq == drv->pre_freq) {
+ volt = dev_pm_opp_get_voltage(opp);
+ mtk_ccifreq_set_voltage(drv, volt);
+ }
+ mutex_unlock(&drv->reg_lock);
+ }
+
+ return 0;
+}
+
+static struct devfreq_dev_profile mtk_ccifreq_profile = {
+ .target = mtk_ccifreq_target,
+};
+
+static int mtk_ccifreq_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct mtk_ccifreq_drv *drv;
+ struct devfreq_passive_data *passive_data;
+ struct dev_pm_opp *opp;
+ unsigned long rate, opp_volt;
+ int ret;
+
+ drv = devm_kzalloc(dev, sizeof(*drv), GFP_KERNEL);
+ if (!drv)
+ return -ENOMEM;
+
+ drv->dev = dev;
+ drv->soc_data = (const struct mtk_ccifreq_platform_data *)
+ of_device_get_match_data(&pdev->dev);
+ mutex_init(&drv->reg_lock);
+ platform_set_drvdata(pdev, drv);
+
+ drv->cci_clk = devm_clk_get(dev, "cci");
+ if (IS_ERR(drv->cci_clk)) {
+ ret = PTR_ERR(drv->cci_clk);
+ return dev_err_probe(dev, ret, "failed to get cci clk\n");
+ }
+
+ drv->inter_clk = devm_clk_get(dev, "intermediate");
+ if (IS_ERR(drv->inter_clk)) {
+ ret = PTR_ERR(drv->inter_clk);
+ return dev_err_probe(dev, ret,
+ "failed to get intermediate clk\n");
+ }
+
+ drv->proc_reg = devm_regulator_get_optional(dev, "proc");
+ if (IS_ERR(drv->proc_reg)) {
+ ret = PTR_ERR(drv->proc_reg);
+ return dev_err_probe(dev, ret,
+ "failed to get proc regulator\n");
+ }
+
+ ret = regulator_enable(drv->proc_reg);
+ if (ret) {
+ dev_err(dev, "failed to enable proc regulator\n");
+ return ret;
+ }
+
+ drv->sram_reg = devm_regulator_get_optional(dev, "sram");
+ if (IS_ERR(drv->sram_reg)) {
+ ret = PTR_ERR(drv->sram_reg);
+ if (ret == -EPROBE_DEFER)
+ goto out_free_resources;
+
+ drv->sram_reg = NULL;
+ } else {
+ ret = regulator_enable(drv->sram_reg);
+ if (ret) {
+ dev_err(dev, "failed to enable sram regulator\n");
+ goto out_free_resources;
+ }
+ }
+
+ /*
+ * We assume min voltage is 0 and tracking target voltage using
+ * min_volt_shift for each iteration.
+ * The retry_max is 3 times of expected iteration count.
+ */
+ drv->vtrack_max = 3 * DIV_ROUND_UP(max(drv->soc_data->sram_max_volt,
+ drv->soc_data->proc_max_volt),
+ drv->soc_data->min_volt_shift);
+
+ ret = clk_prepare_enable(drv->cci_clk);
+ if (ret)
+ goto out_free_resources;
+
+ ret = dev_pm_opp_of_add_table(dev);
+ if (ret) {
+ dev_err(dev, "failed to add opp table: %d\n", ret);
+ goto out_disable_cci_clk;
+ }
+
+ rate = clk_get_rate(drv->inter_clk);
+ opp = dev_pm_opp_find_freq_ceil(dev, &rate);
+ if (IS_ERR(opp)) {
+ ret = PTR_ERR(opp);
+ dev_err(dev, "failed to get intermediate opp: %d\n", ret);
+ goto out_remove_opp_table;
+ }
+ drv->inter_voltage = dev_pm_opp_get_voltage(opp);
+ dev_pm_opp_put(opp);
+
+ rate = U32_MAX;
+ opp = dev_pm_opp_find_freq_floor(drv->dev, &rate);
+ if (IS_ERR(opp)) {
+ dev_err(dev, "failed to get opp\n");
+ ret = PTR_ERR(opp);
+ goto out_remove_opp_table;
+ }
+
+ opp_volt = dev_pm_opp_get_voltage(opp);
+ dev_pm_opp_put(opp);
+ ret = mtk_ccifreq_set_voltage(drv, opp_volt);
+ if (ret) {
+ dev_err(dev, "failed to scale to highest voltage %lu in proc_reg\n",
+ opp_volt);
+ goto out_remove_opp_table;
+ }
+
+ passive_data = devm_kzalloc(dev, sizeof(*passive_data), GFP_KERNEL);
+ if (!passive_data) {
+ ret = -ENOMEM;
+ goto out_remove_opp_table;
+ }
+
+ passive_data->parent_type = CPUFREQ_PARENT_DEV;
+ drv->devfreq = devm_devfreq_add_device(dev, &mtk_ccifreq_profile,
+ DEVFREQ_GOV_PASSIVE,
+ passive_data);
+ if (IS_ERR(drv->devfreq)) {
+ ret = -EPROBE_DEFER;
+ dev_err(dev, "failed to add devfreq device: %ld\n",
+ PTR_ERR(drv->devfreq));
+ goto out_remove_opp_table;
+ }
+
+ drv->opp_nb.notifier_call = mtk_ccifreq_opp_notifier;
+ ret = dev_pm_opp_register_notifier(dev, &drv->opp_nb);
+ if (ret) {
+ dev_err(dev, "failed to register opp notifier: %d\n", ret);
+ goto out_remove_opp_table;
+ }
+ return 0;
+
+out_remove_opp_table:
+ dev_pm_opp_of_remove_table(dev);
+
+out_disable_cci_clk:
+ clk_disable_unprepare(drv->cci_clk);
+
+out_free_resources:
+ if (regulator_is_enabled(drv->proc_reg))
+ regulator_disable(drv->proc_reg);
+ if (!IS_ERR_OR_NULL(drv->sram_reg) &&
+ regulator_is_enabled(drv->sram_reg))
+ regulator_disable(drv->sram_reg);
+
+ return ret;
+}
+
+static void mtk_ccifreq_remove(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct mtk_ccifreq_drv *drv;
+
+ drv = platform_get_drvdata(pdev);
+
+ dev_pm_opp_unregister_notifier(dev, &drv->opp_nb);
+ dev_pm_opp_of_remove_table(dev);
+ clk_disable_unprepare(drv->cci_clk);
+ regulator_disable(drv->proc_reg);
+ if (drv->sram_reg)
+ regulator_disable(drv->sram_reg);
+}
+
+static const struct mtk_ccifreq_platform_data mt8183_platform_data = {
+ .min_volt_shift = 100000,
+ .max_volt_shift = 200000,
+ .proc_max_volt = 1150000,
+};
+
+static const struct mtk_ccifreq_platform_data mt8186_platform_data = {
+ .min_volt_shift = 100000,
+ .max_volt_shift = 250000,
+ .proc_max_volt = 1118750,
+ .sram_min_volt = 850000,
+ .sram_max_volt = 1118750,
+};
+
+static const struct of_device_id mtk_ccifreq_machines[] = {
+ { .compatible = "mediatek,mt8183-cci", .data = &mt8183_platform_data },
+ { .compatible = "mediatek,mt8186-cci", .data = &mt8186_platform_data },
+ { },
+};
+MODULE_DEVICE_TABLE(of, mtk_ccifreq_machines);
+
+static struct platform_driver mtk_ccifreq_platdrv = {
+ .probe = mtk_ccifreq_probe,
+ .remove = mtk_ccifreq_remove,
+ .driver = {
+ .name = "mtk-ccifreq",
+ .of_match_table = mtk_ccifreq_machines,
+ },
+};
+module_platform_driver(mtk_ccifreq_platdrv);
+
+MODULE_DESCRIPTION("MediaTek CCI devfreq driver");
+MODULE_AUTHOR("Jia-Wei Chang <jia-wei.chang@mediatek.com>");
+MODULE_LICENSE("GPL v2");