o) Remove default MAXMEM on SWARM; pmap can readily use lmem for >512M

   physical addresses.
o) Set a local maxmem in sb_machdep.c to avoid trying to use pages over 2^64
   under 32-bit ABIs.  Our pmap needs corrected to use vm_paddr_t consistently,
   then we can make vm_paddr_t 64-bit under 32-bit ABIs and add code in pmap
   to limit phys_avail by the maximum PFN that a 32-bit PTE can hold.

1 files changed, 11 insertions, 0 deletions

diff --git a/sys/mips/sibyte/sb_machdep.c b/sys/mips/sibyte/sb_machdep.c
index dca2869..559bf74 100644
--- a/sys/mips/sibyte/sb_machdep.c
+++ b/sys/mips/sibyte/sb_machdep.c
@@ -158,6 +158,17 @@ mips_init(void)
 	TUNABLE_INT_FETCH("hw.physmem", &tmp);
 	maxmem = (uint64_t)tmp * 1024;
 
+	/*
+	 * XXX
+	 * If we used vm_paddr_t consistently in pmap, etc., we could
+	 * use 64-bit page numbers on !n64 systems, too, like i386
+	 * does with PAE.
+	 */
+#if !defined(__mips_n64)
+	if (maxmem == 0 || maxmem > 0xffffffff)
+		maxmem = 0xffffffff;
+#endif
+
 #ifdef CFE
 	/*
 	 * Query DRAM memory map from CFE.