From 759cbb4ee971da13ddfa8ad73befc2351d542044 Mon Sep 17 00:00:00 2001 From: Juraj Marcin Date: Wed, 4 Sep 2024 12:37:13 +0200 Subject: reset: Add RESET_TYPE_WAKEUP Some devices need to distinguish cold start reset from waking up from a suspended state. This patch adds new value to the enum, and updates the i386 wakeup method to use this new reset type. Message-ID: <20240904103722.946194-3-jmarcin@redhat.com> Reviewed-by: David Hildenbrand Signed-off-by: Juraj Marcin Signed-off-by: David Hildenbrand --- docs/devel/reset.rst | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) (limited to 'docs/devel') diff --git a/docs/devel/reset.rst b/docs/devel/reset.rst index ed41e09f16..74c7c0171a 100644 --- a/docs/devel/reset.rst +++ b/docs/devel/reset.rst @@ -44,6 +44,17 @@ The Resettable interface handles reset types with an enum ``ResetType``: value on each cold reset, such as RNG seed information, and which they must not reinitialize on a snapshot-load reset. +``RESET_TYPE_WAKEUP`` + If the machine supports waking up from a suspended state and needs to reset + its devices during wake-up (from the ``MachineClass::wakeup()`` method), this + reset type should be used for such a request. Devices can utilize this reset + type to differentiate the reset requested during machine wake-up from other + reset requests. For example, RAM content must not be lost during wake-up, and + memory devices like virtio-mem that provide additional RAM must not reset + such state during wake-ups, but might do so during cold resets. However, this + reset type should not be used for wake-up detection, as not every machine + type issues a device reset request during wake-up. + ``RESET_TYPE_S390_CPU_NORMAL`` This is only used for S390 CPU objects; it clears interrupts, stops processing, and clears the TLB, but does not touch register contents. @@ -53,7 +64,6 @@ The Resettable interface handles reset types with an enum ``ResetType``: ``RESET_TYPE_S390_CPU_NORMAL`` does and also clears the PSW, prefix, FPC, timer and control registers. It does not touch gprs, fprs or acrs. - Devices which implement reset methods must treat any unknown ``ResetType`` as equivalent to ``RESET_TYPE_COLD``; this will reduce the amount of existing code we need to change if we add more types in future. -- cgit 1.4.1