| /* |
| * Copyright (c) 2013-2014, The Linux Foundation. All rights reserved. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 and |
| * only version 2 as published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| */ |
| |
| #define pr_fmt(fmt) "devbw: " fmt |
| |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/init.h> |
| #include <linux/io.h> |
| #include <linux/delay.h> |
| #include <linux/ktime.h> |
| #include <linux/time.h> |
| #include <linux/err.h> |
| #include <linux/errno.h> |
| #include <linux/mutex.h> |
| #include <linux/interrupt.h> |
| #include <linux/devfreq.h> |
| #include <linux/of.h> |
| #include <trace/events/power.h> |
| #include <linux/msm-bus.h> |
| #include <linux/msm-bus-board.h> |
| |
| /* Has to be ULL to prevent overflow where this macro is used. */ |
| #define MBYTE (1ULL << 20) |
| #define MAX_PATHS 2 |
| #define DBL_BUF 2 |
| |
| struct dev_data { |
| struct msm_bus_vectors vectors[MAX_PATHS * DBL_BUF]; |
| struct msm_bus_paths bw_levels[DBL_BUF]; |
| struct msm_bus_scale_pdata bw_data; |
| int num_paths; |
| u32 bus_client; |
| int cur_idx; |
| int cur_ab; |
| int cur_ib; |
| long gov_ab; |
| unsigned int ab_percent; |
| struct devfreq *df; |
| struct devfreq_dev_profile dp; |
| }; |
| |
| static int set_bw(struct device *dev, int new_ib, int new_ab) |
| { |
| struct dev_data *d = dev_get_drvdata(dev); |
| int i, ret; |
| |
| if (d->cur_ib == new_ib && d->cur_ab == new_ab) |
| return 0; |
| |
| i = (d->cur_idx + 1) % DBL_BUF; |
| |
| d->bw_levels[i].vectors[0].ib = new_ib * MBYTE; |
| d->bw_levels[i].vectors[0].ab = new_ab / d->num_paths * MBYTE; |
| d->bw_levels[i].vectors[1].ib = new_ib * MBYTE; |
| d->bw_levels[i].vectors[1].ab = new_ab / d->num_paths * MBYTE; |
| |
| dev_dbg(dev, "BW MBps: AB: %d IB: %d\n", new_ab, new_ib); |
| |
| ret = msm_bus_scale_client_update_request(d->bus_client, i); |
| if (ret) { |
| dev_err(dev, "bandwidth request failed (%d)\n", ret); |
| } else { |
| d->cur_idx = i; |
| d->cur_ib = new_ib; |
| d->cur_ab = new_ab; |
| } |
| |
| return ret; |
| } |
| |
| static unsigned int find_ab(struct dev_data *d, unsigned long *freq) |
| { |
| return (d->ab_percent * (*freq)) / 100; |
| } |
| |
| static void find_freq(struct devfreq_dev_profile *p, unsigned long *freq, |
| u32 flags) |
| { |
| int i; |
| unsigned long atmost, atleast, f; |
| |
| atmost = p->freq_table[0]; |
| atleast = p->freq_table[p->max_state-1]; |
| for (i = 0; i < p->max_state; i++) { |
| f = p->freq_table[i]; |
| if (f <= *freq) |
| atmost = max(f, atmost); |
| if (f >= *freq) |
| atleast = min(f, atleast); |
| } |
| |
| if (flags & DEVFREQ_FLAG_LEAST_UPPER_BOUND) |
| *freq = atmost; |
| else |
| *freq = atleast; |
| } |
| |
| static int devbw_target(struct device *dev, unsigned long *freq, u32 flags) |
| { |
| struct dev_data *d = dev_get_drvdata(dev); |
| |
| find_freq(&d->dp, freq, flags); |
| |
| if (!d->gov_ab) |
| return set_bw(dev, *freq, find_ab(d, freq)); |
| else |
| return set_bw(dev, *freq, d->gov_ab); |
| } |
| |
| static int devbw_get_dev_status(struct device *dev, |
| struct devfreq_dev_status *stat) |
| { |
| struct dev_data *d = dev_get_drvdata(dev); |
| |
| stat->private_data = &d->gov_ab; |
| return 0; |
| } |
| |
| #define PROP_PORTS "qcom,src-dst-ports" |
| #define PROP_TBL "qcom,bw-tbl" |
| #define PROP_AB_PER "qcom,ab-percent" |
| #define PROP_ACTIVE "qcom,active-only" |
| |
| int devfreq_add_devbw(struct device *dev) |
| { |
| struct dev_data *d; |
| struct devfreq_dev_profile *p; |
| u32 *data, ports[MAX_PATHS * 2]; |
| const char *gov_name; |
| int ret, len, i, num_paths; |
| |
| d = devm_kzalloc(dev, sizeof(*d), GFP_KERNEL); |
| if (!d) |
| return -ENOMEM; |
| dev_set_drvdata(dev, d); |
| |
| if (of_find_property(dev->of_node, PROP_PORTS, &len)) { |
| len /= sizeof(ports[0]); |
| if (len % 2 || len > ARRAY_SIZE(ports)) { |
| dev_err(dev, "Unexpected number of ports\n"); |
| return -EINVAL; |
| } |
| |
| ret = of_property_read_u32_array(dev->of_node, PROP_PORTS, |
| ports, len); |
| if (ret) |
| return ret; |
| |
| num_paths = len / 2; |
| } else { |
| return -EINVAL; |
| } |
| |
| d->bw_levels[0].vectors = &d->vectors[0]; |
| d->bw_levels[1].vectors = &d->vectors[MAX_PATHS]; |
| d->bw_data.usecase = d->bw_levels; |
| d->bw_data.num_usecases = ARRAY_SIZE(d->bw_levels); |
| d->bw_data.name = dev_name(dev); |
| d->bw_data.active_only = of_property_read_bool(dev->of_node, |
| PROP_ACTIVE); |
| |
| for (i = 0; i < num_paths; i++) { |
| d->bw_levels[0].vectors[i].src = ports[2 * i]; |
| d->bw_levels[0].vectors[i].dst = ports[2 * i + 1]; |
| d->bw_levels[1].vectors[i].src = ports[2 * i]; |
| d->bw_levels[1].vectors[i].dst = ports[2 * i + 1]; |
| } |
| d->bw_levels[0].num_paths = num_paths; |
| d->bw_levels[1].num_paths = num_paths; |
| d->num_paths = num_paths; |
| |
| p = &d->dp; |
| p->polling_ms = 50; |
| p->target = devbw_target; |
| p->get_dev_status = devbw_get_dev_status; |
| |
| if (of_find_property(dev->of_node, PROP_TBL, &len)) { |
| len /= sizeof(*data); |
| data = devm_kzalloc(dev, len * sizeof(*data), GFP_KERNEL); |
| if (!data) |
| return -ENOMEM; |
| |
| p->freq_table = devm_kzalloc(dev, |
| len * sizeof(*p->freq_table), |
| GFP_KERNEL); |
| if (!p->freq_table) |
| return -ENOMEM; |
| |
| ret = of_property_read_u32_array(dev->of_node, PROP_TBL, |
| data, len); |
| if (ret) |
| return ret; |
| |
| for (i = 0; i < len; i++) |
| p->freq_table[i] = data[i]; |
| p->max_state = len; |
| } |
| |
| if (of_find_property(dev->of_node, PROP_AB_PER, &len)) { |
| ret = of_property_read_u32(dev->of_node, PROP_AB_PER, |
| &d->ab_percent); |
| if (ret) |
| return ret; |
| |
| dev_dbg(dev, "ab-percent used %u\n", d->ab_percent); |
| } |
| |
| d->bus_client = msm_bus_scale_register_client(&d->bw_data); |
| if (!d->bus_client) { |
| dev_err(dev, "Unable to register bus client\n"); |
| return -ENODEV; |
| } |
| |
| if (of_property_read_string(dev->of_node, "governor", &gov_name)) |
| gov_name = "performance"; |
| |
| d->df = devfreq_add_device(dev, p, gov_name, NULL); |
| if (IS_ERR(d->df)) { |
| msm_bus_scale_unregister_client(d->bus_client); |
| return PTR_ERR(d->df); |
| } |
| |
| return 0; |
| } |
| |
| int devfreq_remove_devbw(struct device *dev) |
| { |
| struct dev_data *d = dev_get_drvdata(dev); |
| msm_bus_scale_unregister_client(d->bus_client); |
| devfreq_remove_device(d->df); |
| return 0; |
| } |
| |
| int devfreq_suspend_devbw(struct device *dev) |
| { |
| struct dev_data *d = dev_get_drvdata(dev); |
| return devfreq_suspend_device(d->df); |
| } |
| |
| int devfreq_resume_devbw(struct device *dev) |
| { |
| struct dev_data *d = dev_get_drvdata(dev); |
| return devfreq_resume_device(d->df); |
| } |
| |
| static int devfreq_devbw_probe(struct platform_device *pdev) |
| { |
| return devfreq_add_devbw(&pdev->dev); |
| } |
| |
| static int devfreq_devbw_remove(struct platform_device *pdev) |
| { |
| return devfreq_remove_devbw(&pdev->dev); |
| } |
| |
| static struct of_device_id match_table[] = { |
| { .compatible = "qcom,devbw" }, |
| {} |
| }; |
| |
| static struct platform_driver devbw_driver = { |
| .probe = devfreq_devbw_probe, |
| .remove = devfreq_devbw_remove, |
| .driver = { |
| .name = "devbw", |
| .of_match_table = match_table, |
| .owner = THIS_MODULE, |
| }, |
| }; |
| |
| static int __init devbw_init(void) |
| { |
| platform_driver_register(&devbw_driver); |
| return 0; |
| } |
| device_initcall(devbw_init); |
| |
| MODULE_DESCRIPTION("Device DDR bandwidth voting driver MSM SoCs"); |
| MODULE_LICENSE("GPL v2"); |