powerpc/64: Provide functions for accessing POWER9 partition table

POWER9 requires the host to set up a partition table, which is a
table in memory indexed by logical partition ID (LPID) which
contains the pointers to page tables and process tables for the
host and each guest.

This factors out the initialization of the partition table into
a single function.  This code was previously duplicated between
hash_utils_64.c and pgtable-radix.c.

This provides a function for setting a partition table entry,
which is used in early MMU initialization, and will be used by
KVM whenever a guest is created.  This function includes a tlbie
instruction which will flush all TLB entries for the LPID and
all caches of the partition table entry for the LPID, across the
system.

This also moves a call to memblock_set_current_limit(), which was
in radix_init_partition_table(), but has nothing to do with the
partition table.  By analogy with the similar code for hash, the
call gets moved to near the end of radix__early_init_mmu().  It
now gets called when running as a guest, whereas previously it
would only be called if the kernel is running as the host.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

1 files changed, 4 insertions, 24 deletions

diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index 44d3c3a38e3e..b9a062f5805b 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -792,37 +792,17 @@ static void update_hid_for_hash(void)
 static void __init hash_init_partition_table(phys_addr_t hash_table,
 					     unsigned long htab_size)
 {
-	unsigned long ps_field;
-	unsigned long patb_size = 1UL << PATB_SIZE_SHIFT;
+	mmu_partition_table_init();
 
 	/*
-	 * slb llp encoding for the page size used in VPM real mode.
-	 * We can ignore that for lpid 0
+	 * PS field (VRMA page size) is not used for LPID 0, hence set to 0.
+	 * For now, UPRT is 0 and we have no segment table.
 	 */
-	ps_field = 0;
 	htab_size =  __ilog2(htab_size) - 18;
-
-	BUILD_BUG_ON_MSG((PATB_SIZE_SHIFT > 24), "Partition table size too large.");
-	partition_tb = __va(memblock_alloc_base(patb_size, patb_size,
-						MEMBLOCK_ALLOC_ANYWHERE));
-
-	/* Initialize the Partition Table with no entries */
-	memset((void *)partition_tb, 0, patb_size);
-	partition_tb->patb0 = cpu_to_be64(ps_field | hash_table | htab_size);
-	/*
-	 * FIXME!! This should be done via update_partition table
-	 * For now UPRT is 0 for us.
-	 */
-	partition_tb->patb1 = 0;
+	mmu_partition_table_set_entry(0, hash_table | htab_size, 0);
 	pr_info("Partition table %p\n", partition_tb);
 	if (cpu_has_feature(CPU_FTR_POWER9_DD1))
 		update_hid_for_hash();
-	/*
-	 * update partition table control register,
-	 * 64 K size.
-	 */
-	mtspr(SPRN_PTCR, __pa(partition_tb) | (PATB_SIZE_SHIFT - 12));
-
 }
 
 static void __init htab_initialize(void)