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spapr: Support ibm,dynamic-reconfiguration-memory

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Parse ibm,architecture.vec table obtained from the guest and enable
memory node configuration via ibm,dynamic-reconfiguration-memory if guest
supports it. This is in preparation to support memory hotplug for
sPAPR guests.

This changes the way memory node configuration is done. Currently all
memory nodes are built upfront. But after this patch, only memory@0 node
for RMA is built upfront. Guest kernel boots with just that and rest of
the memory nodes (via memory@XXX or ibm,dynamic-reconfiguration-memory)
are built when guest does ibm,client-architecture-support call.

Note: This patch needs a SLOF enhancement which is already part of
SLOF binary in QEMU.

Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This commit is contained in:
Bharata B Rao 2015-07-13 10:34:00 +10:00 • committed by David Gibson
parent 224245bf52
commit 03d196b7c5
4 changed files with 274 additions and 50 deletions
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48
docs/specs/ppc-spapr-hotplug.txt
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@ -302,4 +302,52 @@ consisting of <phys>, <size> and <maxcpus>.
pseries guests use this property to note the maximum allowed CPUs for the
guest.
== ibm,dynamic-reconfiguration-memory ==
ibm,dynamic-reconfiguration-memory is a device tree node that represents
dynamically reconfigurable logical memory blocks (LMB). This node
is generated only when the guest advertises the support for it via
ibm,client-architecture-support call. Memory that is not dynamically
reconfigurable is represented by /memory nodes. The properties of this
node that are of interest to the sPAPR memory hotplug implementation
in QEMU are described here.
ibm,lmb-size
This 64bit integer defines the size of each dynamically reconfigurable LMB.
ibm,associativity-lookup-arrays
This property defines a lookup array in which the NUMA associativity
information for each LMB can be found. It is a property encoded array
that begins with an integer M, the number of associativity lists followed
by an integer N, the number of entries per associativity list and terminated
by M associativity lists each of length N integers.
This property provides the same information as given by ibm,associativity
property in a /memory node. Each assigned LMB has an index value between
0 and M-1 which is used as an index into this table to select which
associativity list to use for the LMB. This index value for each LMB
is defined in ibm,dynamic-memory property.
ibm,dynamic-memory
This property describes the dynamically reconfigurable memory. It is a
property encoded array that has an integer N, the number of LMBs followed
by N LMB list entires.
Each LMB list entry consists of the following elements:
- Logical address of the start of the LMB encoded as a 64bit integer. This
corresponds to reg property in /memory node.
- DRC index of the LMB that corresponds to ibm,my-drc-index property
in a /memory node.
- Four bytes reserved for expansion.
- Associativity list index for the LMB that is used as an index into
ibm,associativity-lookup-arrays property described earlier. This
is used to retrieve the right associativity list to be used for this
LMB.
- A 32bit flags word. The bit at bit position 0x00000008 defines whether
the LMB is assigned to the the partition as of boot time.
[1] http://thread.gmane.org/gmane.linux.ports.ppc.embedded/75350/focus=106867