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authorPaul Mackerras <paulus@samba.org>2006-11-29 22:27:42 +1100
committerPaul Mackerras <paulus@samba.org>2006-12-11 13:49:49 +1100
commit0204568a088fecd5478153504f9476ee2c46d5bf (patch)
tree6c22d9590bbedd3b4ba22e53737c37c6862f5e48 /arch/powerpc/mm
parenta223535425eb28082a0925b0ce2f02f962936cf4 (diff)
[POWERPC] Support ibm,dynamic-reconfiguration-memory nodes
For PAPR partitions with large amounts of memory, the firmware has an alternative, more compact representation for the information about the memory in the partition and its NUMA associativity information. This adds the code to the kernel to parse this alternative representation. The other part of this patch is telling the firmware that we can handle the alternative representation. There is however a subtlety here, because the firmware will invoke a reboot if the memory representation we request is different from the representation that firmware is currently using. This is because firmware can't change the representation on the fly. Further, some firmware versions used on POWER5+ machines have a bug where this reboot leaves the machine with an altered value of load-base, which will prevent any kernel booting until it is reset to the normal value (0x4000). Because of this bug, we do NOT set fake_elf.rpanote.new_mem_def = 1, and thus we do not request the new representation on POWER5+ and earlier machines. We do request the new representation on POWER6, which uses the ibm,client-architecture-support call. Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'arch/powerpc/mm')
-rw-r--r--arch/powerpc/mm/numa.c65
1 files changed, 65 insertions, 0 deletions
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index 9da01dc8cfd..262790910ff 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -295,6 +295,63 @@ static unsigned long __init numa_enforce_memory_limit(unsigned long start,
return lmb_end_of_DRAM() - start;
}
+/*
+ * Extract NUMA information from the ibm,dynamic-reconfiguration-memory
+ * node. This assumes n_mem_{addr,size}_cells have been set.
+ */
+static void __init parse_drconf_memory(struct device_node *memory)
+{
+ const unsigned int *lm, *dm, *aa;
+ unsigned int ls, ld, la;
+ unsigned int n, aam, aalen;
+ unsigned long lmb_size, size;
+ int nid, default_nid = 0;
+ unsigned int start, ai, flags;
+
+ lm = get_property(memory, "ibm,lmb-size", &ls);
+ dm = get_property(memory, "ibm,dynamic-memory", &ld);
+ aa = get_property(memory, "ibm,associativity-lookup-arrays", &la);
+ if (!lm || !dm || !aa ||
+ ls < sizeof(unsigned int) || ld < sizeof(unsigned int) ||
+ la < 2 * sizeof(unsigned int))
+ return;
+
+ lmb_size = read_n_cells(n_mem_size_cells, &lm);
+ n = *dm++; /* number of LMBs */
+ aam = *aa++; /* number of associativity lists */
+ aalen = *aa++; /* length of each associativity list */
+ if (ld < (n * (n_mem_addr_cells + 4) + 1) * sizeof(unsigned int) ||
+ la < (aam * aalen + 2) * sizeof(unsigned int))
+ return;
+
+ for (; n != 0; --n) {
+ start = read_n_cells(n_mem_addr_cells, &dm);
+ ai = dm[2];
+ flags = dm[3];
+ dm += 4;
+ /* 0x80 == reserved, 0x8 = assigned to us */
+ if ((flags & 0x80) || !(flags & 0x8))
+ continue;
+ nid = default_nid;
+ /* flags & 0x40 means associativity index is invalid */
+ if (min_common_depth > 0 && min_common_depth <= aalen &&
+ (flags & 0x40) == 0 && ai < aam) {
+ /* this is like of_node_to_nid_single */
+ nid = aa[ai * aalen + min_common_depth - 1];
+ if (nid == 0xffff || nid >= MAX_NUMNODES)
+ nid = default_nid;
+ }
+ node_set_online(nid);
+
+ size = numa_enforce_memory_limit(start, lmb_size);
+ if (!size)
+ continue;
+
+ add_active_range(nid, start >> PAGE_SHIFT,
+ (start >> PAGE_SHIFT) + (size >> PAGE_SHIFT));
+ }
+}
+
static int __init parse_numa_properties(void)
{
struct device_node *cpu = NULL;
@@ -385,6 +442,14 @@ new_range:
goto new_range;
}
+ /*
+ * Now do the same thing for each LMB listed in the ibm,dynamic-memory
+ * property in the ibm,dynamic-reconfiguration-memory node.
+ */
+ memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
+ if (memory)
+ parse_drconf_memory(memory);
+
return 0;
}