diff options
Diffstat (limited to 'drivers/devfreq/tegra20-devfreq.c')
| -rw-r--r-- | drivers/devfreq/tegra20-devfreq.c | 212 |
1 files changed, 0 insertions, 212 deletions
diff --git a/drivers/devfreq/tegra20-devfreq.c b/drivers/devfreq/tegra20-devfreq.c deleted file mode 100644 index ff82bac9ee4e..000000000000 --- a/drivers/devfreq/tegra20-devfreq.c +++ /dev/null @@ -1,212 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * NVIDIA Tegra20 devfreq driver - * - * Copyright (C) 2019 GRATE-DRIVER project - */ - -#include <linux/clk.h> -#include <linux/devfreq.h> -#include <linux/io.h> -#include <linux/kernel.h> -#include <linux/module.h> -#include <linux/of_device.h> -#include <linux/platform_device.h> -#include <linux/pm_opp.h> -#include <linux/slab.h> - -#include <soc/tegra/mc.h> - -#include "governor.h" - -#define MC_STAT_CONTROL 0x90 -#define MC_STAT_EMC_CLOCK_LIMIT 0xa0 -#define MC_STAT_EMC_CLOCKS 0xa4 -#define MC_STAT_EMC_CONTROL 0xa8 -#define MC_STAT_EMC_COUNT 0xb8 - -#define EMC_GATHER_CLEAR (1 << 8) -#define EMC_GATHER_ENABLE (3 << 8) - -struct tegra_devfreq { - struct devfreq *devfreq; - struct clk *emc_clock; - void __iomem *regs; -}; - -static int tegra_devfreq_target(struct device *dev, unsigned long *freq, - u32 flags) -{ - struct tegra_devfreq *tegra = dev_get_drvdata(dev); - struct devfreq *devfreq = tegra->devfreq; - struct dev_pm_opp *opp; - unsigned long rate; - int err; - - opp = devfreq_recommended_opp(dev, freq, flags); - if (IS_ERR(opp)) - return PTR_ERR(opp); - - rate = dev_pm_opp_get_freq(opp); - dev_pm_opp_put(opp); - - err = clk_set_min_rate(tegra->emc_clock, rate); - if (err) - return err; - - err = clk_set_rate(tegra->emc_clock, 0); - if (err) - goto restore_min_rate; - - return 0; - -restore_min_rate: - clk_set_min_rate(tegra->emc_clock, devfreq->previous_freq); - - return err; -} - -static int tegra_devfreq_get_dev_status(struct device *dev, - struct devfreq_dev_status *stat) -{ - struct tegra_devfreq *tegra = dev_get_drvdata(dev); - - /* - * EMC_COUNT returns number of memory events, that number is lower - * than the number of clocks. Conversion ratio of 1/8 results in a - * bit higher bandwidth than actually needed, it is good enough for - * the time being because drivers don't support requesting minimum - * needed memory bandwidth yet. - * - * TODO: adjust the ratio value once relevant drivers will support - * memory bandwidth management. - */ - stat->busy_time = readl_relaxed(tegra->regs + MC_STAT_EMC_COUNT); - stat->total_time = readl_relaxed(tegra->regs + MC_STAT_EMC_CLOCKS) / 8; - stat->current_frequency = clk_get_rate(tegra->emc_clock); - - writel_relaxed(EMC_GATHER_CLEAR, tegra->regs + MC_STAT_CONTROL); - writel_relaxed(EMC_GATHER_ENABLE, tegra->regs + MC_STAT_CONTROL); - - return 0; -} - -static struct devfreq_dev_profile tegra_devfreq_profile = { - .polling_ms = 500, - .target = tegra_devfreq_target, - .get_dev_status = tegra_devfreq_get_dev_status, -}; - -static struct tegra_mc *tegra_get_memory_controller(void) -{ - struct platform_device *pdev; - struct device_node *np; - struct tegra_mc *mc; - - np = of_find_compatible_node(NULL, NULL, "nvidia,tegra20-mc-gart"); - if (!np) - return ERR_PTR(-ENOENT); - - pdev = of_find_device_by_node(np); - of_node_put(np); - if (!pdev) - return ERR_PTR(-ENODEV); - - mc = platform_get_drvdata(pdev); - if (!mc) - return ERR_PTR(-EPROBE_DEFER); - - return mc; -} - -static int tegra_devfreq_probe(struct platform_device *pdev) -{ - struct tegra_devfreq *tegra; - struct tegra_mc *mc; - unsigned long max_rate; - unsigned long rate; - int err; - - mc = tegra_get_memory_controller(); - if (IS_ERR(mc)) { - err = PTR_ERR(mc); - dev_err(&pdev->dev, "failed to get memory controller: %d\n", - err); - return err; - } - - tegra = devm_kzalloc(&pdev->dev, sizeof(*tegra), GFP_KERNEL); - if (!tegra) - return -ENOMEM; - - /* EMC is a system-critical clock that is always enabled */ - tegra->emc_clock = devm_clk_get(&pdev->dev, "emc"); - if (IS_ERR(tegra->emc_clock)) { - err = PTR_ERR(tegra->emc_clock); - dev_err(&pdev->dev, "failed to get emc clock: %d\n", err); - return err; - } - - tegra->regs = mc->regs; - - max_rate = clk_round_rate(tegra->emc_clock, ULONG_MAX); - - for (rate = 0; rate <= max_rate; rate++) { - rate = clk_round_rate(tegra->emc_clock, rate); - - err = dev_pm_opp_add(&pdev->dev, rate, 0); - if (err) { - dev_err(&pdev->dev, "failed to add opp: %d\n", err); - goto remove_opps; - } - } - - /* - * Reset statistic gathers state, select global bandwidth for the - * statistics collection mode and set clocks counter saturation - * limit to maximum. - */ - writel_relaxed(0x00000000, tegra->regs + MC_STAT_CONTROL); - writel_relaxed(0x00000000, tegra->regs + MC_STAT_EMC_CONTROL); - writel_relaxed(0xffffffff, tegra->regs + MC_STAT_EMC_CLOCK_LIMIT); - - platform_set_drvdata(pdev, tegra); - - tegra->devfreq = devfreq_add_device(&pdev->dev, &tegra_devfreq_profile, - DEVFREQ_GOV_SIMPLE_ONDEMAND, NULL); - if (IS_ERR(tegra->devfreq)) { - err = PTR_ERR(tegra->devfreq); - goto remove_opps; - } - - return 0; - -remove_opps: - dev_pm_opp_remove_all_dynamic(&pdev->dev); - - return err; -} - -static int tegra_devfreq_remove(struct platform_device *pdev) -{ - struct tegra_devfreq *tegra = platform_get_drvdata(pdev); - - devfreq_remove_device(tegra->devfreq); - dev_pm_opp_remove_all_dynamic(&pdev->dev); - - return 0; -} - -static struct platform_driver tegra_devfreq_driver = { - .probe = tegra_devfreq_probe, - .remove = tegra_devfreq_remove, - .driver = { - .name = "tegra20-devfreq", - }, -}; -module_platform_driver(tegra_devfreq_driver); - -MODULE_ALIAS("platform:tegra20-devfreq"); -MODULE_AUTHOR("Dmitry Osipenko <digetx@gmail.com>"); -MODULE_DESCRIPTION("NVIDIA Tegra20 devfreq driver"); -MODULE_LICENSE("GPL v2"); |