xref: /OK3568_Linux_fs/kernel/Documentation/scsi/link_power_management_policy.rst (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun.. SPDX-License-Identifier: GPL-2.0
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3*4882a593Smuzhiyun==========================
4*4882a593SmuzhiyunLink Power Managent Policy
5*4882a593Smuzhiyun==========================
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7*4882a593SmuzhiyunThis parameter allows the user to set the link (interface) power management.
8*4882a593SmuzhiyunThere are 3 possible options:
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10*4882a593Smuzhiyun=====================   =====================================================
11*4882a593SmuzhiyunValue			Effect
12*4882a593Smuzhiyun=====================   =====================================================
13*4882a593Smuzhiyunmin_power		Tell the controller to try to make the link use the
14*4882a593Smuzhiyun			least possible power when possible.  This may
15*4882a593Smuzhiyun			sacrifice some performance due to increased latency
16*4882a593Smuzhiyun			when coming out of lower power states.
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18*4882a593Smuzhiyunmax_performance		Generally, this means no power management.  Tell
19*4882a593Smuzhiyun			the controller to have performance be a priority
20*4882a593Smuzhiyun			over power management.
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22*4882a593Smuzhiyunmedium_power		Tell the controller to enter a lower power state
23*4882a593Smuzhiyun			when possible, but do not enter the lowest power
24*4882a593Smuzhiyun			state, thus improving latency over min_power setting.
25*4882a593Smuzhiyun=====================   =====================================================
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