zh_CN/power/opp.rst

1 .. SPDX-License-Identifier: GPL-2.0
2 .. include:: ../disclaimer-zh_CN.rst
4 :Original: Documentation/power/opp.rst
11 操作性能值（OPP）库
14 (C) 2009-2010 Nishanth Menon <nm@ti.com>, 德州仪器公司
28 1.1 何为操作性能值（OPP）？
29 ------------------------------
46 - {300000000, 1000000}
47 - {800000000, 1200000}
48 - {1000000000, 1300000}
51 ----------------
53 OPP库提供了一组辅助函数来组织和查询OPP信息。该库位于drivers/opp/目录下，其头文件
59  （用户）        -> 注册一个默认的OPP集合               -> （库）
60  （SoC框架）     -> 在必要的情况下，对某些OPP进行修改     -> OPP layer
61                 -> 搜索/检索信息的查询                 ->
64 OPP。这个链表的长度被期望是一个最优化的小数字，通常每个设备大约5个。初始链表包含了
89 方式注册OPP条目 - 典型的数字范围小于5。通过注册OPP生成的OPP链表，在整个设备运行过程
109 			pr_err("%s: unable to register mpu opp(%d)\n", r);
132 	 opp = dev_pm_opp_find_freq_exact(dev, 1000000000, false);
133 	 dev_pm_opp_put(opp);
135 	 if (IS_ERR(opp)) {
139 		dev_pm_opp_enable(dev,1000000000);
151 	 opp = dev_pm_opp_find_freq_floor(dev, &freq);
152 	 dev_pm_opp_put(opp);
160 	 opp = dev_pm_opp_find_freq_ceil(dev, &freq);
161 	 dev_pm_opp_put(opp);
163 	例: 一个SoC的cpufreq_driver->target的简易实现::
169 		opp = dev_pm_opp_find_freq_ceil(dev, &freq);
170 		dev_pm_opp_put(opp);
171 		if (!IS_ERR(opp))
195 		opp = dev_pm_opp_find_freq_exact(dev, 1000000000, false);
196 		dev_pm_opp_put(opp);
198 		if (!IS_ERR(opp))
199 			ret = dev_pm_opp_enable(dev, 1000000000);
211 		opp = dev_pm_opp_find_freq_exact(dev, 1000000000, true);
212 		dev_pm_opp_put(opp);
214 		if (!IS_ERR(opp))
215 			ret = dev_pm_opp_disable(dev, 1000000000);
234 		opp = dev_pm_opp_find_freq_ceil(dev, &freq);
235 		v = dev_pm_opp_get_voltage(opp);
236 		dev_pm_opp_put(opp);
262 			 return -EINVAL;
264 			 return -EINVAL;
280 		while (!IS_ERR(opp = dev_pm_opp_find_freq_ceil(dev, &freq))) {
284 			dev_pm_opp_put(opp);
297    |- device 1
298    |	|- opp 1 (availability, freq, voltage)
299    |	|- opp 2 ..
301    |	`- opp n ..
302    |- device 2
304    `- device m
326               +-----+        /- dev_pm_opp_enable
327   dev_pm_opp_add --> | opp | <-------
328     |         +-----+        \- dev_pm_opp_disable
329     \-------> domain_info(device)
332                /-- dev_pm_opp_find_freq_ceil  ---\   +-----+
333   domain_info<---- dev_pm_opp_find_freq_exact -----> | opp |
334                \-- dev_pm_opp_find_freq_floor ---/   +-----+
337   +-----+     /- dev_pm_opp_get_voltage
338   | opp | <---
339   +-----+     \- dev_pm_opp_get_freq
341   domain_info <- dev_pm_opp_get_opp_count