Commit Graph

8 Commits

Author SHA1 Message Date
Bill Richardson
41cde66516 Samus: Handle fan startup in the EC, not the fan controller
The fans on samus have a recommended minimum duty cycle of 20%
while running, but 30% in order to start. We've been using the
EC's built-in fan controller for the start requirement, but it
has a minimum fast-start duty cycle of 50%. It turns out that
that speed is noticeably noisy.

This change handles the startup with logic in the EC instead, so
that the fan only tries to spin at 30% initially (or if it drops
too much below the minimum turning speed).

BUG=chrome-os-partner:33429
BRANCH=ToT,samus
TEST=make buildall -j

Boot the system, let it idle with the browser windows closed, the
browse a bit, then idle. Listen for changes to the fans.

Before, I could hear the fans kick in and out as the AP load
changed. Now it's much quieter.

Change-Id: Id35215520c064eb6843686ec8bb5f3618dac6cf6
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/227658
Reviewed-by: Randall Spangler <rspangler@chromium.org>
2014-11-06 02:28:22 +00:00
Bill Richardson
8cd9856cf8 samus: change fan RPM values, enable fast-start
Updating the fan speeds according to the manufacturer's specs.

The fan vendor recommends that the minimum fan speed be a 20%
duty cycle. Since the built-in fan controller has a tach-based
feedback loop, I'm using the RPM value instead of the duty cycle
(20% is 2286 RPM, according to the vendor).

The vendor also wants a 30% duty cycle to start turning, but the
built-in fan controller provides support for fast-start too. The
controller's minimum fast-start duty cycle is 50%, but it also
has a programmable number of revolutions that it will wait before
backing off.

Holding my ear down close to the fans while they start and stop,
it seems that the minimum 2 revolution start period is sufficient
and provides the least noise. Of course, since I've never had any
problems starting the fans directly at 1000 RPM this noise is a
little more noticeable than that. It's quite possible that the
built-in controller is smart enough to make 1000 RPM work by
bumping the duty cycle up until the fans turn even if the fans
don't like it.

BUG=chrome-os-partner:32892
BRANCH=ToT,samus
TEST=manual

Listen closely and run the EC console "faninfo" command to see
the fans start and stop as the system boots and idles.

Change-Id: I47c9e7cef3f9f4bd815a13032fe10234decd62ed
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/224830
Reviewed-by: Randall Spangler <rspangler@chromium.org>
2014-10-22 02:23:39 +00:00
Bill Richardson
88503ab4ec Provide multiple fan support within the EC itself
This adds explicit "int fan" args to the exported functions from
common/fan.c: fan_set_percent_needed() and fan_percent_to_rpm(). Within that
file, multiple fans are handled independently.

This is not complete, though. Host commands and sysjump support still only
handle a single fan, so at the moment multiple fans are treated identically
in those cases.

BUG=chrome-os-partner:23530
BRANCH=none
TEST=manual

All boards build, "make runtests" passes.

On a multi-fan system, the EC command "faninfo" displays multiple results:

  > faninfo
  Fan 0 Actual:    0 rpm
  Fan 0 Target:    0 rpm
  Fan 0 Duty:   0%
  Fan 0 Status: 0 (not spinning)
  Fan 0 Mode:   rpm
  Fan 0 Auto:   yes
  Fan 0 Enable: yes

  Fan 1 Actual:    0 rpm
  Fan 1 Target:    0 rpm
  Fan 1 Duty:   0%
  Fan 1 Status: 0 (not spinning)
  Fan 1 Mode:   rpm
  Fan 1 Auto:   no
  Fan 1 Enable: no
  >

and the "fanduty", "fanset", and "fanauto" all require the fan number as the
first arg:

  > fanduty 0 30
  Setting fan 0 duty cycle to 30%
  > fanset 1 2000
  Setting fan 1 rpm target to 2000
  > fanauto 0
  > fanauto 1

On single-fan systems, there is no visible change.

Change-Id: Idb8b818122e157960d56779b2a86e5ba433bee1b
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/175368
Reviewed-by: Randall Spangler <rspangler@chromium.org>
2013-11-02 01:07:16 +00:00
Bill Richardson
e48a9d9c21 Separate fan_t from pwm_t
There is a logical difference between PWM controls for things like
backlights and fan controls for actual fans. This change separates them into
two different data structures, for better abstraction.

BUG=chrome-os-partner:23530
BRANCH=none
TEST=manual

make runtests, make all boards, test on Link and Falco.

Change-Id: Ib63f2d1518fcc2ee367f81bf5d803360c1aa5c76
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/175151
2013-10-30 23:10:10 +00:00
Bill Richardson
9dff30d466 Add more descriptive comments to include/fan.h
Just adding some comments.

BUG=chrome-os-partner:23530
BRANCH=none
TEST=none

Change-Id: Ib3955e9d97ad8aa642e6fe298c17e34d2c66fb1c
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/175139
2013-10-30 23:10:02 +00:00
Bill Richardson
c7b930606b Separate common fan behavior from implementation
This looks like a lot, but it's really just moving the non-board-specific
stuff from chip/lm4/fan.c into common/fan.c, updating the appropriate
headers, and renaming functions to better match the new location.

This is entirely code refactoring and renaming. No new functionality.

BUG=chrome-os-partner:23530
BRANCH=none
TEST=manual

make runtests, build all platforms, build and test on Link.

Change-Id: I7dc03d6732bad83cf838a86600b42a7cff5aa7aa
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/175012
2013-10-30 21:51:50 +00:00
Bill Richardson
9a6e464502 cleanup: remove obsolete declaration from header
When we cleaned up the alternate function GPIO initialization, we left a
declaration for configure_fan_gpios() in fan.h. That function doesn't exist
anywhere, so there's no point in declaring it.

BUG=chrome-os-partner:18343
BRANCH=none
TEST=manual

Build everything. Nothing fails.

Change-Id: I3d1fe1ff62e523aa7c87d57c5e838b01a0c6e899
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/174334
Reviewed-by: Randall Spangler <rspangler@chromium.org>
2013-10-23 23:53:27 +00:00
Bill Richardson
fcce7223a5 Completely new thermal/fan implementation
Problems with existing thermal control loop:
* Not multi-board friendly. thermal.c only supports Link and needs
  refactoring. Temp thresholds and fan speeds are hard-coded.
* Only the PECI temp is used to determine the fan speed. Other temp sensors
  are ignored.
* Has confusing data structures. Values in the CPU temp thresholds array mix
  ACPI thresholds with fan step values.

With this change, the thermal task monitors all temp sensors in order to
perform two completely independent functions:

Function one: Determine if the host needs to be throttled by or informed of
              any thermal events.

For thermal events, each temp sensor will have three threshold levels.

TEMP_HOST_WARN
* When any sensor goes above this level, host_throttle_cpu(1) will be called
  to ask the CPU to slow itself down.
* When all sensors drop below this level, host_throttle_cpu(0) will be called.
* Exactly AT this level, nothing happens (this provides hysteresis).

TEMP_HOST_HIGH
* When any sensor goes above this level, chipset_throttle_cpu(1) will be
  called to slow the CPU down whether it wants to or not.
* When all sensors drop below this level, chipset_throttle_cpu(0) will be
  called.
* Exactly AT this level, nothing happens (this provides hysteresis).

TEMP_HOST_SHUTDOWN
* When any sensor is above this level, chipset_force_shutdown() will be
  called to halt the CPU.
* Nothing turns the CPU back on again - the user just has to wait for things
  to cool off. Pressing the power button too soon will just trigger shutdown
  again as soon as the EC can read the host temp.

Function two: Determine the amount of fan cooling needed

For fan cooling, each temp sensor will have two levels.

TEMP_FAN_OFF
* At or below this temperature, no active cooling is needed.

TEMP_FAN_MAX
* At or above this temperature, active cooling should be running at maximum.

The highest level of all temp sensors will be used to request the amount of
active cooling needed. The function pwm_fan_percent_to_rpm() is invoked to
convert the amount of cooling to the target fan RPM.

The default pwm_fan_percent_to_rpm() function converts smoothly between the
configured CONFIG_PWM_FAN_RPM_MIN and CONFIG_PWM_FAN_RPM_MAX for percentages
between 1 and 100. 0% means "off".

The default function probably provide the smoothest and quietest behavior,
but individual boards can provide their own pwm_fan_percent_to_rpm() to
implement whatever curves, hysteresis, feedback, or other hackery they wish.

BUG=chrome-os-partner:20805
BRANCH=none
TEST=manual

Compile-time test with

  make BOARD=falco runtests

On the EC console, the existing fan commands should work correctly:

  faninfo       - display the fan state
  fanduty NUM   - force the fan PWM to the specified percentage (0-100)
  fanset RPM    - force the fan to the specified RPM
  fanset NUM%   - force the fan to the specified percentage (0-100) between
                  its configured minimum and maximum speeds from board.h
                  (CONFIG_PWM_FAN_RPM_MIN and CONFIG_PWM_FAN_RPM_MAX)
  fanauto       - let the EC control the fan automatically

You can test the default pwm_fan_percent_to_rpm() with

  fanset 1%
  faninfo

The fan should be turning at CONFIG_PWM_FAN_RPM_MIN. Let the EC control it
automatically again with

  fanauto

Also on the EC console, the thermal settings can be examined or changed:

  > temps
  PECI                : 327 K = 54 C
  ECInternal          : 320 K = 47 C
  G781Internal        : 319 K = 46 C
  G781External        : 318 K = 45 C
  >
  > thermalget
  sensor  warn  high  shutdown   fan_off fan_max   name
    0      373   387    383        333     363     PECI
    1        0     0      0          0       0     ECInternal
    2        0     0      0          0       0     G781Internal
    3        0     0      0          0       0     G781External
  >
  > help thermalset
  Usage: thermalset sensor warn [high [shutdown [fan_off [fan_max]]]]
  set thermal parameters (-1 to skip)
  >
  > thermalset 2 -1 -1 999
  sensor  warn  high  shutdown   fan_off fan_max   name
    0      373   387    383        333     363     PECI
    1        0     0      0          0       0     ECInternal
    2        0     0    999          0       0     G781Internal
    3        0     0      0          0       0     G781External
  >

From the host, ectool can be used to get and set these parameters with
nearly identical commands:

  ectool thermalget
  ectool thermalset 2 -1 -1 999

Change-Id: Idb27977278f766826045fb7d41929953ec6b1cca
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/66688
Reviewed-by: Randall Spangler <rspangler@chromium.org>
2013-08-23 10:38:36 -07:00