sparc64: Increase MAX_PHYS_ADDRESS_BITS to 53.
Make sure, at compile time, that the kernel can properly support
whatever MAX_PHYS_ADDRESS_BITS is defined to.
On M7 chips, use a max_phys_bits value of 49.
Based upon a patch by Bob Picco.
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Bob Picco <bob.picco@oracle.com>
diff --git a/arch/sparc/include/asm/page_64.h b/arch/sparc/include/asm/page_64.h
index 732ba17..6784a33 100644
--- a/arch/sparc/include/asm/page_64.h
+++ b/arch/sparc/include/asm/page_64.h
@@ -122,11 +122,11 @@
#endif /* !(__ASSEMBLY__) */
-/* The maximum number of physical memory address bits we support, this
- * is used to size various tables used to manage kernel TLB misses and
- * also the sparsemem code.
+/* The maximum number of physical memory address bits we support. The
+ * largest value we can support is whatever "KPGD_SHIFT + KPTE_BITS"
+ * evaluates to.
*/
-#define MAX_PHYS_ADDRESS_BITS 47
+#define MAX_PHYS_ADDRESS_BITS 53
#define ILOG2_4MB 22
#define ILOG2_256MB 28
diff --git a/arch/sparc/include/asm/pgtable_64.h b/arch/sparc/include/asm/pgtable_64.h
index a305b22..0552957 100644
--- a/arch/sparc/include/asm/pgtable_64.h
+++ b/arch/sparc/include/asm/pgtable_64.h
@@ -67,6 +67,10 @@
#define PGDIR_MASK (~(PGDIR_SIZE-1))
#define PGDIR_BITS (PAGE_SHIFT - 3)
+#if (MAX_PHYS_ADDRESS_BITS > PGDIR_SHIFT + PGDIR_BITS)
+#error MAX_PHYS_ADDRESS_BITS exceeds what kernel page tables can support
+#endif
+
#if (PGDIR_SHIFT + PGDIR_BITS) != 53
#error Page table parameters do not cover virtual address space properly.
#endif
diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c
index 6d5d562..e0c1206 100644
--- a/arch/sparc/mm/init_64.c
+++ b/arch/sparc/mm/init_64.c
@@ -1690,12 +1690,19 @@
case SUN4V_CHIP_NIAGARA4:
case SUN4V_CHIP_NIAGARA5:
case SUN4V_CHIP_SPARC64X:
- default:
+ case SUN4V_CHIP_SPARC_M6:
/* T4 and later support 52-bit virtual addresses. */
sparc64_va_hole_top = 0xfff8000000000000UL;
sparc64_va_hole_bottom = 0x0008000000000000UL;
max_phys_bits = 47;
break;
+ case SUN4V_CHIP_SPARC_M7:
+ default:
+ /* M7 and later support 52-bit virtual addresses. */
+ sparc64_va_hole_top = 0xfff8000000000000UL;
+ sparc64_va_hole_bottom = 0x0008000000000000UL;
+ max_phys_bits = 49;
+ break;
}
}