[PATCH 3/3][v2] OMAP:iommu- add TLB preservation support

["Kanigeri, Hari" <h-kanigeri2@xxxxxx>]

>From 2cecc5abd54c7a139495d135260a6a66810318e8 Mon Sep 17 00:00:00 2001
From: Hari Kanigeri <h-kanigeri2@xxxxxx>
Date: Tue, 20 Apr 2010 12:11:16 -0500
Subject: [PATCH 3/3] OMAP:iommu- add TLB preservation support

This patch adds TLB preservation support to IOMMU module

Signed-off-by: Hari Kanigeri <h-kanigeri2@xxxxxx>
---
 arch/arm/mach-omap2/iommu2.c |    4 +++-
 arch/arm/plat-omap/iommu.c   |   12 ++++++++----
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/arch/arm/mach-omap2/iommu2.c b/arch/arm/mach-omap2/iommu2.c
index f01f985..5ce76e4 100644
--- a/arch/arm/mach-omap2/iommu2.c
+++ b/arch/arm/mach-omap2/iommu2.c
@@ -146,6 +146,7 @@ static u32 omap2_iommu_fault_isr(struct iommu *obj, u32 *ra)
 	printk("\n");
 
 	iommu_write_reg(obj, stat, MMU_IRQSTATUS);
+	omap2_iommu_disable(obj);
 	return stat;
 }
 
@@ -211,7 +212,8 @@ static ssize_t omap2_dump_cr(struct iommu *obj, struct cr_regs *cr, char *buf)
 	char *p = buf;
 
 	/* FIXME: Need more detail analysis of cam/ram */
-	p += sprintf(p, "%08x %08x\n", cr->cam, cr->ram);
+	p += sprintf(p, "%08x %08x %01x\n", cr->cam, cr->ram,
+					(cr->cam & MMU_CAM_P) ? 1 : 0);
 
 	return p - buf;
 }
diff --git a/arch/arm/plat-omap/iommu.c b/arch/arm/plat-omap/iommu.c
index 463d638..a1d4ccf 100644
--- a/arch/arm/plat-omap/iommu.c
+++ b/arch/arm/plat-omap/iommu.c
@@ -171,15 +171,12 @@ static void iotlb_lock_get(struct iommu *obj, struct iotlb_lock *l)
 	l->base = MMU_LOCK_BASE(val);
 	l->vict = MMU_LOCK_VICT(val);
 
-	BUG_ON(l->base != 0); /* Currently no preservation is used */
 }
 
 static void iotlb_lock_set(struct iommu *obj, struct iotlb_lock *l)
 {
 	u32 val;
 
-	BUG_ON(l->base != 0); /* Currently no preservation is used */
-
 	val = (l->base << MMU_LOCK_BASE_SHIFT);
 	val |= (l->vict << MMU_LOCK_VICT_SHIFT);
 
@@ -241,6 +238,11 @@ int load_iotlb_entry(struct iommu *obj, struct iotlb_entry *e)
 			break;
 	}
 
+	if (l.base == obj->nr_tlb_entries) {
+		dev_dbg(obj->dev, "%s: preserve entries full\n", __func__);
+		err = -EBUSY;
+		goto out;
+	}
 	if (i == obj->nr_tlb_entries) {
 		dev_dbg(obj->dev, "%s: full: no entry\n", __func__);
 		err = -EBUSY;
@@ -256,9 +258,11 @@ int load_iotlb_entry(struct iommu *obj, struct iotlb_entry *e)
 	iotlb_load_cr(obj, cr);
 	kfree(cr);
 
+	if (e->prsvd)
+		l.base++;
 	/* increment victim for next tlb load */
 	if (++l.vict == obj->nr_tlb_entries)
-		l.vict = 0;
+		l.vict = l.base;
 	iotlb_lock_set(obj, &l);
 out:
 	clk_disable(obj->clk);
-- 
1.7.0


Thank you,
Best regards,
Hari

Attachment: 0003-OMAP-iommu-add-TLB-preservation-support.patch
Description: 0003-OMAP-iommu-add-TLB-preservation-support.patch