MIPS: dump_tlb: Preserve and dump GuestID

The GuestID for root TLB operations (GuestCtl1.RID) is modified by TLB
reads, so needs preserving by dump_tlb() like the ASID field of EntryHi.

Also dump the GuestID of each entry if it exists alongside the ASID, as
it forms an important part of the TLB entry when VZ guests are used.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/13230/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/lib/dump_tlb.c

@@ -72,7 +72,8 @@ static void dump_tlb(int first, int last)
 {
 	unsigned long s_entryhi, entryhi, asid;
 	unsigned long long entrylo0, entrylo1, pa;
-	unsigned int s_index, s_pagemask, pagemask, c0, c1, i;
+	unsigned int s_index, s_pagemask, s_guestctl1 = 0;
+	unsigned int pagemask, guestctl1 = 0, c0, c1, i;
 	unsigned long asidmask = cpu_asid_mask(&current_cpu_data);
 	int asidwidth = DIV_ROUND_UP(ilog2(asidmask) + 1, 4);
 #ifdef CONFIG_32BIT
@@ -89,6 +90,8 @@ static void dump_tlb(int first, int last)
 	s_entryhi = read_c0_entryhi();
 	s_index = read_c0_index();
 	asid = s_entryhi & asidmask;
+	if (cpu_has_guestid)
+		s_guestctl1 = read_c0_guestctl1();
 
 	for (i = first; i <= last; i++) {
 		write_c0_index(i);
@@ -99,6 +102,8 @@ static void dump_tlb(int first, int last)
 		entryhi	 = read_c0_entryhi();
 		entrylo0 = read_c0_entrylo0();
 		entrylo1 = read_c0_entrylo1();
+		if (cpu_has_guestid)
+			guestctl1 = read_c0_guestctl1();
 
 		/* EHINV bit marks entire entry as invalid */
 		if (cpu_has_tlbinv && entryhi & MIPS_ENTRYHI_EHINV)
@@ -128,15 +133,19 @@ static void dump_tlb(int first, int last)
 		c0 = (entrylo0 & ENTRYLO_C) >> ENTRYLO_C_SHIFT;
 		c1 = (entrylo1 & ENTRYLO_C) >> ENTRYLO_C_SHIFT;
 
-		printk("va=%0*lx asid=%0*lx\n",
+		printk("va=%0*lx asid=%0*lx",
 		       vwidth, (entryhi & ~0x1fffUL),
 		       asidwidth, entryhi & asidmask);
+		if (cpu_has_guestid)
+			printk(" gid=%02lx",
+			       (guestctl1 & MIPS_GCTL1_RID)
+					>> MIPS_GCTL1_RID_SHIFT);
 		/* RI/XI are in awkward places, so mask them off separately */
 		pa = entrylo0 & ~(MIPS_ENTRYLO_RI | MIPS_ENTRYLO_XI);
 		if (xpa)
 			pa |= (unsigned long long)readx_c0_entrylo0() << 30;
 		pa = (pa << 6) & PAGE_MASK;
-		printk("\t[");
+		printk("\n\t[");
 		if (cpu_has_rixi)
 			printk("ri=%d xi=%d ",
 			       (entrylo0 & MIPS_ENTRYLO_RI) ? 1 : 0,
@@ -166,6 +175,8 @@ static void dump_tlb(int first, int last)
 	write_c0_entryhi(s_entryhi);
 	write_c0_index(s_index);
 	write_c0_pagemask(s_pagemask);
+	if (cpu_has_guestid)
+		write_c0_guestctl1(s_guestctl1);
 }
 
 void dump_tlb_all(void)