Commit Graph

4 Commits

Author SHA1 Message Date
Hao Wu 71b50b9d1c hw/misc: Add GPIOs for duty in NPCM7xx PWM
This patch adds GPIOs in NPCM7xx PWM module for its duty values.
The purpose of this is to connect it to the MFT module to provide
an input for measuring a PWM fan's RPM. Each PWM module has
NPCM7XX_PWM_PER_MODULE of GPIOs, each one corresponds to
one PWM instance and can connect to multiple fan instances in MFT.

Reviewed-by: Doug Evans <dje@google.com>
Reviewed-by: Tyrone Ting <kfting@nuvoton.com>
Signed-off-by: Hao Wu <wuhaotsh@google.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20210311180855.149764-2-wuhaotsh@google.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-03-12 12:48:56 +00:00
Peter Maydell 5ee0abed51 clock: Add ClockEvent parameter to callbacks
The Clock framework allows users to specify a callback which is
called after the clock's period has been updated.  Some users need to
also have a callback which is called before the clock period is
updated.

As the first step in adding support for notifying Clock users on
pre-update events, add an argument to the ClockCallback to specify
what event is being notified, and add an argument to the various
functions for registering a callback to specify which events are
of interest to that callback.

Note that the documentation update renders correct the previously
incorrect claim in 'Adding a new clock' that callbacks "will be
explained in a following section".

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Luc Michel <luc@lmichel.fr>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210219144617.4782-2-peter.maydell@linaro.org
2021-03-08 17:20:01 +00:00
Hao Wu 1e5ce6e10a hw/misc: Fix arith overflow in NPCM7XX PWM module
Fix potential overflow problem when calculating pwm_duty.
1. Ensure p->cmr and p->cnr to be from [0,65535], according to the
   hardware specification.
2. Changed duty to uint32_t. However, since MAX_DUTY * (p->cmr+1)
   can excceed UINT32_MAX, we convert them to uint64_t in computation
   and converted them back to uint32_t.
   (duty is guaranteed to be <= MAX_DUTY so it won't overflow.)

Fixes: CID 1442342
Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Doug Evans <dje@google.com>
Signed-off-by: Hao Wu <wuhaotsh@google.com>
Message-id: 20210127011142.2122790-1-wuhaotsh@google.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-29 10:47:28 +00:00
Hao Wu 1e943c586a hw/misc: Add a PWM module for NPCM7XX
The PWM module is part of NPCM7XX module. Each NPCM7XX module has two
identical PWM modules. Each module contains 4 PWM entries. Each PWM has
two outputs: frequency and duty_cycle. Both are computed using inputs
from software side.

This module does not model detail pulse signals since it is expensive.
It also does not model interrupts and watchdogs that are dependant on
the detail models. The interfaces for these are left in the module so
that anyone in need for these functionalities can implement on their
own.

The user can read the duty cycle and frequency using qom-get command.

Reviewed-by: Havard Skinnemoen <hskinnemoen@google.com>
Reviewed-by: Tyrone Ting <kfting@nuvoton.com>
Signed-off-by: Hao Wu <wuhaotsh@google.com>
Message-id: 20210108190945.949196-5-wuhaotsh@google.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2021-01-12 21:19:02 +00:00