spapr: Move DT memory node rendering to a helper

This moves recurring bits of code related to memory@xxx nodes
creation to a helper.

This makes use of the new helper for node@0.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alexander Graf <agraf@suse.de>
spapr: Use DT memory node rendering helper for other nodes

This finishes refactoring by using the spapr_populate_memory_node helper
for all nodes and removing leftovers from spapr_populate_memory().

This is not a part of the previous patch because the patches look
nicer apart.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alexander Graf <agraf@suse.de>
spapr: Refactor spapr_populate_memory() to allow memoryless nodes

Current QEMU does not support memoryless NUMA nodes, however
actual hardware may have them so it makes sense to have a way
to emulate them in QEMU. This prepares SPAPR for that.

This moves 2 calls of spapr_populate_memory_node() into
the existing loop over numa nodes so first several nodes may
have no memory and this still will work.

If there is no numa configuration, the code assumes there is just
a single node at 0 and it has all the guest memory.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alexander Graf <agraf@suse.de>
spapr: Split memory nodes to power-of-two blocks

Linux kernel expects nodes to have power-of-two size and
does WARN_ON if this is not the case:
[    0.041456] WARNING: at drivers/base/memory.c:115
which is:

===
	/* Validate blk_sz is a power of 2 and not less than section size */
	if ((block_sz & (block_sz - 1)) || (block_sz < MIN_MEMORY_BLOCK_SIZE)) {
        	WARN_ON(1);
	        block_sz = MIN_MEMORY_BLOCK_SIZE;
	}
===

This splits memory nodes into set of smaller blocks with
a size which is a power of two. This makes sure the start
address of every node is aligned to the node size.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alexander Graf <agraf@suse.de>
spapr: Add a helper for node0_size calculation

In multiple places there is a node0_size variable calculation
which assumes that NUMA node #0 and memory node #0 are the same
things which they are not. Since we are going to change it and
do not want to change it in multiple places, let's make a helper.

This adds a spapr_node0_size() helper and makes use of it.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alexander Graf <agraf@suse.de>
spapr: Fix ibm, associativity for memory nodes

We want the associtivity lists of memory and CPU nodes to match but
memory nodes have incorrect domain#3 which is zero for CPU so they won't
match.

This clears domain#3 in the list to match CPUs associtivity lists.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alexander Graf <agraf@suse.de>