2 * exynos-nocp.c - EXYNOS NoC (Network On Chip) Probe support
4 * Copyright (c) 2016 Samsung Electronics Co., Ltd.
5 * Author : Chanwoo Choi <cw00.choi@samsung.com>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
12 #include <linux/clk.h>
13 #include <linux/module.h>
14 #include <linux/devfreq-event.h>
15 #include <linux/kernel.h>
16 #include <linux/of_address.h>
17 #include <linux/platform_device.h>
18 #include <linux/regmap.h>
20 #include "exynos-nocp.h"
23 struct devfreq_event_dev *edev;
24 struct devfreq_event_desc desc;
28 struct regmap *regmap;
33 * The devfreq-event ops structure for nocp probe.
35 static int exynos_nocp_set_event(struct devfreq_event_dev *edev)
37 struct exynos_nocp *nocp = devfreq_event_get_drvdata(edev);
40 /* Disable NoC probe */
41 ret = regmap_update_bits(nocp->regmap, NOCP_MAIN_CTL,
42 NOCP_MAIN_CTL_STATEN_MASK, 0);
44 dev_err(nocp->dev, "failed to disable the NoC probe device\n");
48 /* Set a statistics dump period to 0 */
49 ret = regmap_write(nocp->regmap, NOCP_STAT_PERIOD, 0x0);
53 /* Set the IntEvent fields of *_SRC */
54 ret = regmap_update_bits(nocp->regmap, NOCP_COUNTERS_0_SRC,
55 NOCP_CNT_SRC_INTEVENT_MASK,
56 NOCP_CNT_SRC_INTEVENT_BYTE_MASK);
60 ret = regmap_update_bits(nocp->regmap, NOCP_COUNTERS_1_SRC,
61 NOCP_CNT_SRC_INTEVENT_MASK,
62 NOCP_CNT_SRC_INTEVENT_CHAIN_MASK);
66 ret = regmap_update_bits(nocp->regmap, NOCP_COUNTERS_2_SRC,
67 NOCP_CNT_SRC_INTEVENT_MASK,
68 NOCP_CNT_SRC_INTEVENT_CYCLE_MASK);
72 ret = regmap_update_bits(nocp->regmap, NOCP_COUNTERS_3_SRC,
73 NOCP_CNT_SRC_INTEVENT_MASK,
74 NOCP_CNT_SRC_INTEVENT_CHAIN_MASK);
79 /* Set an alarm with a max/min value of 0 to generate StatALARM */
80 ret = regmap_write(nocp->regmap, NOCP_STAT_ALARM_MIN, 0x0);
84 ret = regmap_write(nocp->regmap, NOCP_STAT_ALARM_MAX, 0x0);
89 ret = regmap_update_bits(nocp->regmap, NOCP_COUNTERS_0_ALARM_MODE,
90 NOCP_CNT_ALARM_MODE_MASK,
91 NOCP_CNT_ALARM_MODE_MIN_MAX_MASK);
95 ret = regmap_update_bits(nocp->regmap, NOCP_COUNTERS_1_ALARM_MODE,
96 NOCP_CNT_ALARM_MODE_MASK,
97 NOCP_CNT_ALARM_MODE_MIN_MAX_MASK);
101 ret = regmap_update_bits(nocp->regmap, NOCP_COUNTERS_2_ALARM_MODE,
102 NOCP_CNT_ALARM_MODE_MASK,
103 NOCP_CNT_ALARM_MODE_MIN_MAX_MASK);
107 ret = regmap_update_bits(nocp->regmap, NOCP_COUNTERS_3_ALARM_MODE,
108 NOCP_CNT_ALARM_MODE_MASK,
109 NOCP_CNT_ALARM_MODE_MIN_MAX_MASK);
113 /* Enable the measurements by setting AlarmEn and StatEn */
114 ret = regmap_update_bits(nocp->regmap, NOCP_MAIN_CTL,
115 NOCP_MAIN_CTL_STATEN_MASK | NOCP_MAIN_CTL_ALARMEN_MASK,
116 NOCP_MAIN_CTL_STATEN_MASK | NOCP_MAIN_CTL_ALARMEN_MASK);
121 ret = regmap_update_bits(nocp->regmap, NOCP_CFG_CTL,
122 NOCP_CFG_CTL_GLOBALEN_MASK,
123 NOCP_CFG_CTL_GLOBALEN_MASK);
127 /* Enable NoC probe */
128 ret = regmap_update_bits(nocp->regmap, NOCP_MAIN_CTL,
129 NOCP_MAIN_CTL_STATEN_MASK,
130 NOCP_MAIN_CTL_STATEN_MASK);
137 /* Reset NoC probe */
138 if (regmap_update_bits(nocp->regmap, NOCP_MAIN_CTL,
139 NOCP_MAIN_CTL_STATEN_MASK, 0)) {
140 dev_err(nocp->dev, "Failed to reset NoC probe device\n");
146 static int exynos_nocp_get_event(struct devfreq_event_dev *edev,
147 struct devfreq_event_data *edata)
149 struct exynos_nocp *nocp = devfreq_event_get_drvdata(edev);
150 unsigned int counter[4];
153 /* Read cycle count */
154 ret = regmap_read(nocp->regmap, NOCP_COUNTERS_0_VAL, &counter[0]);
158 ret = regmap_read(nocp->regmap, NOCP_COUNTERS_1_VAL, &counter[1]);
162 ret = regmap_read(nocp->regmap, NOCP_COUNTERS_2_VAL, &counter[2]);
166 ret = regmap_read(nocp->regmap, NOCP_COUNTERS_3_VAL, &counter[3]);
170 edata->load_count = ((counter[1] << 16) | counter[0]);
171 edata->total_count = ((counter[3] << 16) | counter[2]);
173 dev_dbg(&edev->dev, "%s (event: %ld/%ld)\n", edev->desc->name,
174 edata->load_count, edata->total_count);
179 edata->load_count = 0;
180 edata->total_count = 0;
182 dev_err(nocp->dev, "Failed to read the counter of NoC probe device\n");
187 static const struct devfreq_event_ops exynos_nocp_ops = {
188 .set_event = exynos_nocp_set_event,
189 .get_event = exynos_nocp_get_event,
192 static const struct of_device_id exynos_nocp_id_match[] = {
193 { .compatible = "samsung,exynos5420-nocp", },
197 static struct regmap_config exynos_nocp_regmap_config = {
201 .max_register = NOCP_COUNTERS_3_VAL,
204 static int exynos_nocp_parse_dt(struct platform_device *pdev,
205 struct exynos_nocp *nocp)
207 struct device *dev = nocp->dev;
208 struct device_node *np = dev->of_node;
209 struct resource *res;
213 dev_err(dev, "failed to find devicetree node\n");
217 nocp->clk = devm_clk_get(dev, "nocp");
218 if (IS_ERR(nocp->clk))
221 /* Maps the memory mapped IO to control nocp register */
222 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
223 base = devm_ioremap_resource(dev, res);
225 return PTR_ERR(base);
227 exynos_nocp_regmap_config.max_register = resource_size(res) - 4;
229 nocp->regmap = devm_regmap_init_mmio(dev, base,
230 &exynos_nocp_regmap_config);
231 if (IS_ERR(nocp->regmap)) {
232 dev_err(dev, "failed to initialize regmap\n");
233 return PTR_ERR(nocp->regmap);
239 static int exynos_nocp_probe(struct platform_device *pdev)
241 struct device *dev = &pdev->dev;
242 struct device_node *np = dev->of_node;
243 struct exynos_nocp *nocp;
246 nocp = devm_kzalloc(&pdev->dev, sizeof(*nocp), GFP_KERNEL);
250 nocp->dev = &pdev->dev;
252 /* Parse dt data to get resource */
253 ret = exynos_nocp_parse_dt(pdev, nocp);
256 "failed to parse devicetree for resource\n");
260 /* Add devfreq-event device to measure the bandwidth of NoC */
261 nocp->desc.ops = &exynos_nocp_ops;
262 nocp->desc.driver_data = nocp;
263 nocp->desc.name = np->full_name;
264 nocp->edev = devm_devfreq_event_add_edev(&pdev->dev, &nocp->desc);
265 if (IS_ERR(nocp->edev)) {
267 "failed to add devfreq-event device\n");
268 return PTR_ERR(nocp->edev);
270 platform_set_drvdata(pdev, nocp);
272 clk_prepare_enable(nocp->clk);
274 pr_info("exynos-nocp: new NoC Probe device registered: %s\n",
280 static int exynos_nocp_remove(struct platform_device *pdev)
282 struct exynos_nocp *nocp = platform_get_drvdata(pdev);
284 clk_disable_unprepare(nocp->clk);
289 static struct platform_driver exynos_nocp_driver = {
290 .probe = exynos_nocp_probe,
291 .remove = exynos_nocp_remove,
293 .name = "exynos-nocp",
294 .of_match_table = exynos_nocp_id_match,
297 module_platform_driver(exynos_nocp_driver);
299 MODULE_DESCRIPTION("Exynos NoC (Network on Chip) Probe driver");
300 MODULE_AUTHOR("Chanwoo Choi <cw00.choi@samsung.com>");
301 MODULE_LICENSE("GPL");