From 0204568a088fecd5478153504f9476ee2c46d5bf Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Wed, 29 Nov 2006 22:27:42 +1100 Subject: [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 --- arch/powerpc/kernel/prom.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+) (limited to 'arch/powerpc/kernel/prom.c') diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c index c18dbe77fdc2..1fc732a552db 100644 --- a/arch/powerpc/kernel/prom.c +++ b/arch/powerpc/kernel/prom.c @@ -804,6 +804,56 @@ static unsigned long __init dt_mem_next_cell(int s, cell_t **cellp) return of_read_ulong(p, s); } +#ifdef CONFIG_PPC_PSERIES +/* + * Interpret the ibm,dynamic-memory property in the + * /ibm,dynamic-reconfiguration-memory node. + * This contains a list of memory blocks along with NUMA affinity + * information. + */ +static int __init early_init_dt_scan_drconf_memory(unsigned long node) +{ + cell_t *dm, *ls; + unsigned long l, n; + unsigned long base, size, lmb_size, flags; + + ls = (cell_t *)of_get_flat_dt_prop(node, "ibm,lmb-size", &l); + if (ls == NULL || l < dt_root_size_cells * sizeof(cell_t)) + return 0; + lmb_size = dt_mem_next_cell(dt_root_size_cells, &ls); + + dm = (cell_t *)of_get_flat_dt_prop(node, "ibm,dynamic-memory", &l); + if (dm == NULL || l < sizeof(cell_t)) + return 0; + + n = *dm++; /* number of entries */ + if (l < (n * (dt_root_addr_cells + 4) + 1) * sizeof(cell_t)) + return 0; + + for (; n != 0; --n) { + base = dt_mem_next_cell(dt_root_addr_cells, &dm); + flags = dm[3]; + /* skip DRC index, pad, assoc. list index, flags */ + dm += 4; + /* skip this block if the reserved bit is set in flags (0x80) + or if the block is not assigned to this partition (0x8) */ + if ((flags & 0x80) || !(flags & 0x8)) + continue; + size = lmb_size; + if (iommu_is_off) { + if (base >= 0x80000000ul) + continue; + if ((base + size) > 0x80000000ul) + size = 0x80000000ul - base; + } + lmb_add(base, size); + } + lmb_dump_all(); + return 0; +} +#else +#define early_init_dt_scan_drconf_memory(node) 0 +#endif /* CONFIG_PPC_PSERIES */ static int __init early_init_dt_scan_memory(unsigned long node, const char *uname, int depth, void *data) @@ -812,6 +862,11 @@ static int __init early_init_dt_scan_memory(unsigned long node, cell_t *reg, *endp; unsigned long l; + /* Look for the ibm,dynamic-reconfiguration-memory node */ + if (depth == 1 && + strcmp(uname, "ibm,dynamic-reconfiguration-memory") == 0) + return early_init_dt_scan_drconf_memory(node); + /* We are scanning "memory" nodes only */ if (type == NULL) { /* -- cgit v1.2.2