commit 5a364c2a1762e8a78721fafc93144509c0b6cb84
author Vineet Gupta <vgupta@synopsys.com> Fri Feb 06 18:44:57 2015 +0300
committer Vineet Gupta <vgupta@synopsys.com> Thu Oct 29 18:41:30 2015 +0530
tree dc74e67f8908cbfe0c5753515c8097339d55dc80
parent 25d464183ca3522ae27ec1bbef5ddcbbbef65017

ARC: mm: PAE40 support

This is the first working implementation of 40-bit physical address
extension on ARCv2.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>

arch/arc/mm/tlb.c

diff --git a/arch/arc/mm/tlb.c b/arch/arc/mm/tlb.c
index b5f28dc..0ee7398 100644
--- a/arch/arc/mm/tlb.c
+++ b/arch/arc/mm/tlb.c
@@ -109,6 +109,10 @@
 static inline void __tlb_entry_erase(void)
 {
 	write_aux_reg(ARC_REG_TLBPD1, 0);
+
+	if (is_pae40_enabled())
+		write_aux_reg(ARC_REG_TLBPD1HI, 0);
+
 	write_aux_reg(ARC_REG_TLBPD0, 0);
 	write_aux_reg(ARC_REG_TLBCOMMAND, TLBWrite);
 }
@@ -182,7 +186,7 @@
 
 }
 
-static void tlb_entry_insert(unsigned int pd0, unsigned int pd1)
+static void tlb_entry_insert(unsigned int pd0, pte_t pd1)
 {
 	unsigned int idx;
 
@@ -225,10 +229,14 @@
 	write_aux_reg(ARC_REG_TLBCOMMAND, TLBDeleteEntry);
 }
 
-static void tlb_entry_insert(unsigned int pd0, unsigned int pd1)
+static void tlb_entry_insert(unsigned int pd0, pte_t pd1)
 {
 	write_aux_reg(ARC_REG_TLBPD0, pd0);
 	write_aux_reg(ARC_REG_TLBPD1, pd1);
+
+	if (is_pae40_enabled())
+		write_aux_reg(ARC_REG_TLBPD1HI, (u64)pd1 >> 32);
+
 	write_aux_reg(ARC_REG_TLBCOMMAND, TLBInsertEntry);
 }
 
@@ -249,6 +257,10 @@
 
 	/* Load PD0 and PD1 with template for a Blank Entry */
 	write_aux_reg(ARC_REG_TLBPD1, 0);
+
+	if (is_pae40_enabled())
+		write_aux_reg(ARC_REG_TLBPD1HI, 0);
+
 	write_aux_reg(ARC_REG_TLBPD0, 0);
 
 	for (entry = 0; entry < num_tlb; entry++) {
@@ -503,7 +515,8 @@
 {
 	unsigned long flags;
 	unsigned int asid_or_sasid, rwx;
-	unsigned long pd0, pd1;
+	unsigned long pd0;
+	pte_t pd1;
 
 	/*
 	 * create_tlb() assumes that current->mm == vma->mm, since
@@ -785,10 +798,11 @@
 			  IS_USED_CFG(CONFIG_TRANSPARENT_HUGEPAGE));
 
 	n += scnprintf(buf + n, len - n,
-		      "MMU [v%x]\t: %dK PAGE, %sJTLB %d (%dx%d), uDTLB %d, uITLB %d\n",
+		      "MMU [v%x]\t: %dk PAGE, %sJTLB %d (%dx%d), uDTLB %d, uITLB %d %s%s\n",
 		       p_mmu->ver, p_mmu->pg_sz_k, super_pg,
 		       p_mmu->sets * p_mmu->ways, p_mmu->sets, p_mmu->ways,
-		       p_mmu->u_dtlb, p_mmu->u_itlb);
+		       p_mmu->u_dtlb, p_mmu->u_itlb,
+		       IS_AVAIL2(p_mmu->pae, "PAE40 ", CONFIG_ARC_HAS_PAE40));
 
 	return buf;
 }
@@ -821,6 +835,9 @@
 		panic("MMU Super pg size != Linux HPAGE_PMD_SIZE (%luM)\n",
 		      (unsigned long)TO_MB(HPAGE_PMD_SIZE));
 
+	if (IS_ENABLED(CONFIG_ARC_HAS_PAE40) && !mmu->pae)
+		panic("Hardware doesn't support PAE40\n");
+
 	/* Enable the MMU */
 	write_aux_reg(ARC_REG_PID, MMU_ENABLE);