From 615a55827c590d75bff8a660fc20675fea6c73d3 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Tue, 27 Jul 2021 18:04:11 +0100 Subject: [PATCH] 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 Reviewed-by: Igor Mammedov Message-id: 20210727170414.3368-3-peter.maydell@linaro.org --- docs/specs/acpi_mem_hotplug.rst | 128 ++++++++++++++++++++++++++++++++ docs/specs/acpi_mem_hotplug.txt | 94 ----------------------- docs/specs/index.rst | 1 + 3 files changed, 129 insertions(+), 94 deletions(-) create mode 100644 docs/specs/acpi_mem_hotplug.rst delete mode 100644 docs/specs/acpi_mem_hotplug.txt 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 -- 2.39.5