diff options
author | Peter Maydell <peter.maydell@linaro.org> | 2021-07-27 18:04:11 +0100 |
---|---|---|
committer | Peter Maydell <peter.maydell@linaro.org> | 2021-08-26 17:01:59 +0100 |
commit | 615a55827c590d75bff8a660fc20675fea6c73d3 (patch) | |
tree | 66eef1b6a928a2d05b307575b9e1f3ce870f3dd1 /docs/specs | |
parent | 444fa22549434331db70718f073432ed2057ada8 (diff) |
docs/specs/acpi_mem_hotplug: Convert to rST
Convert the acpi memory hotplug spec to rST.
Note that this includes converting a lot of weird whitespace
characters to plain old spaces (the rST parser does not like
whatever the old ones were).
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Message-id: 20210727170414.3368-3-peter.maydell@linaro.org
Diffstat (limited to 'docs/specs')
-rw-r--r-- | docs/specs/acpi_mem_hotplug.rst | 128 | ||||
-rw-r--r-- | docs/specs/acpi_mem_hotplug.txt | 94 | ||||
-rw-r--r-- | docs/specs/index.rst | 1 |
3 files changed, 129 insertions, 94 deletions
diff --git a/docs/specs/acpi_mem_hotplug.rst b/docs/specs/acpi_mem_hotplug.rst new file mode 100644 index 0000000000..069819bc3e --- /dev/null +++ b/docs/specs/acpi_mem_hotplug.rst @@ -0,0 +1,128 @@ +QEMU<->ACPI BIOS memory hotplug interface +========================================= + +ACPI BIOS GPE.3 handler is dedicated for notifying OS about memory hot-add +and hot-remove events. + +Memory hot-plug interface (IO port 0xa00-0xa17, 1-4 byte access) +---------------------------------------------------------------- + +Read access behavior +^^^^^^^^^^^^^^^^^^^^ + +[0x0-0x3] + Lo part of memory device phys address +[0x4-0x7] + Hi part of memory device phys address +[0x8-0xb] + Lo part of memory device size in bytes +[0xc-0xf] + Hi part of memory device size in bytes +[0x10-0x13] + Memory device proximity domain +[0x14] + Memory device status fields + + bits: + + 0: + Device is enabled and may be used by guest + 1: + Device insert event, used to distinguish device for which + no device check event to OSPM was issued. + It's valid only when bit 1 is set. + 2: + Device remove event, used to distinguish device for which + no device eject request to OSPM was issued. + 3-7: + reserved and should be ignored by OSPM + +[0x15-0x17] + reserved + +Write access behavior +^^^^^^^^^^^^^^^^^^^^^ + + +[0x0-0x3] + Memory device slot selector, selects active memory device. + All following accesses to other registers in 0xa00-0xa17 + region will read/store data from/to selected memory device. +[0x4-0x7] + OST event code reported by OSPM +[0x8-0xb] + OST status code reported by OSPM +[0xc-0x13] + reserved, writes into it are ignored +[0x14] + Memory device control fields + + bits: + + 0: + reserved, OSPM must clear it before writing to register. + Due to BUG in versions prior 2.4 that field isn't cleared + when other fields are written. Keep it reserved and don't + try to reuse it. + 1: + if set to 1 clears device insert event, set by OSPM + after it has emitted device check event for the + selected memory device + 2: + if set to 1 clears device remove event, set by OSPM + after it has emitted device eject request for the + selected memory device + 3: + if set to 1 initiates device eject, set by OSPM when it + triggers memory device removal and calls _EJ0 method + 4-7: + reserved, OSPM must clear them before writing to register + +Selecting memory device slot beyond present range has no effect on platform: + +- write accesses to memory hot-plug registers not documented above are ignored +- read accesses to memory hot-plug registers not documented above return + all bits set to 1. + +Memory hot remove process diagram +--------------------------------- + +:: + + +-------------+ +-----------------------+ +------------------+ + | 1. QEMU | | 2. QEMU | |3. QEMU | + | device_del +---->+ device unplug request +----->+Send SCI to guest,| + | | | cb | |return control to | + | | | | |management | + +-------------+ +-----------------------+ +------------------+ + + +---------------------------------------------------------------------+ + + +---------------------+ +-------------------------+ + | OSPM: | remove event | OSPM: | + | send Eject Request, | | Scan memory devices | + | clear remove event +<-------------+ for event flags | + | | | | + +---------------------+ +-------------------------+ + | + | + +---------v--------+ +-----------------------+ + | Guest OS: | success | OSPM: | + | process Ejection +----------->+ Execute _EJ0 method, | + | request | | set eject bit in flags| + +------------------+ +-----------------------+ + |failure | + v v + +------------------------+ +-----------------------+ + | OSPM: | | QEMU: | + | set OST event & status | | call device unplug cb | + | fields | | | + +------------------------+ +-----------------------+ + | | + v v + +------------------+ +-------------------+ + |QEMU: | |QEMU: | + |Send OST QMP event| |Send device deleted| + | | |QMP event | + +------------------+ | | + +-------------------+ diff --git a/docs/specs/acpi_mem_hotplug.txt b/docs/specs/acpi_mem_hotplug.txt deleted file mode 100644 index 3df3620ce4..0000000000 --- a/docs/specs/acpi_mem_hotplug.txt +++ /dev/null @@ -1,94 +0,0 @@ -QEMU<->ACPI BIOS memory hotplug interface --------------------------------------- - -ACPI BIOS GPE.3 handler is dedicated for notifying OS about memory hot-add -and hot-remove events. - -Memory hot-plug interface (IO port 0xa00-0xa17, 1-4 byte access): ---------------------------------------------------------------- -0xa00: - read access: - [0x0-0x3] Lo part of memory device phys address - [0x4-0x7] Hi part of memory device phys address - [0x8-0xb] Lo part of memory device size in bytes - [0xc-0xf] Hi part of memory device size in bytes - [0x10-0x13] Memory device proximity domain - [0x14] Memory device status fields - bits: - 0: Device is enabled and may be used by guest - 1: Device insert event, used to distinguish device for which - no device check event to OSPM was issued. - It's valid only when bit 1 is set. - 2: Device remove event, used to distinguish device for which - no device eject request to OSPM was issued. - 3-7: reserved and should be ignored by OSPM - [0x15-0x17] reserved - - write access: - [0x0-0x3] Memory device slot selector, selects active memory device. - All following accesses to other registers in 0xa00-0xa17 - region will read/store data from/to selected memory device. - [0x4-0x7] OST event code reported by OSPM - [0x8-0xb] OST status code reported by OSPM - [0xc-0x13] reserved, writes into it are ignored - [0x14] Memory device control fields - bits: - 0: reserved, OSPM must clear it before writing to register. - Due to BUG in versions prior 2.4 that field isn't cleared - when other fields are written. Keep it reserved and don't - try to reuse it. - 1: if set to 1 clears device insert event, set by OSPM - after it has emitted device check event for the - selected memory device - 2: if set to 1 clears device remove event, set by OSPM - after it has emitted device eject request for the - selected memory device - 3: if set to 1 initiates device eject, set by OSPM when it - triggers memory device removal and calls _EJ0 method - 4-7: reserved, OSPM must clear them before writing to register - -Selecting memory device slot beyond present range has no effect on platform: - - write accesses to memory hot-plug registers not documented above are - ignored - - read accesses to memory hot-plug registers not documented above return - all bits set to 1. - -Memory hot remove process diagram: ----------------------------------- - +-------------+ +-----------------------+ +------------------+ - | 1. QEMU | | 2. QEMU | |3. QEMU | - | device_del +---->+ device unplug request +----->+Send SCI to guest,| - | | | cb | |return control to | - +-------------+ +-----------------------+ |management | - +------------------+ - - +---------------------------------------------------------------------+ - - +---------------------+ +-------------------------+ - | OSPM: | remove event | OSPM: | - | send Eject Request, | | Scan memory devices | - | clear remove event +<-------------+ for event flags | - | | | | - +---------------------+ +-------------------------+ - | - | - +---------v--------+ +-----------------------+ - | Guest OS: | success | OSPM: | - | process Ejection +----------->+ Execute _EJ0 method, | - | request | | set eject bit in flags| - +------------------+ +-----------------------+ - |failure | - v v - +------------------------+ +-----------------------+ - | OSPM: | | QEMU: | - | set OST event & status | | call device unplug cb | - | fields | | | - +------------------------+ +-----------------------+ - | | - v v - +------------------+ +-------------------+ - |QEMU: | |QEMU: | - |Send OST QMP event| |Send device deleted| - | | |QMP event | - +------------------+ | | - +-------------------+ diff --git a/docs/specs/index.rst b/docs/specs/index.rst index 24b765e1a4..17cc7868b9 100644 --- a/docs/specs/index.rst +++ b/docs/specs/index.rst @@ -14,3 +14,4 @@ guest hardware that is specific to QEMU. tpm acpi_hest_ghes acpi_cpu_hotplug + acpi_mem_hotplug |