omap iommu: Introduce iteration macro for iotlb entry scan

There are some places to scan iotlb entries. This iteration macro
could make these code a bit simpler with proceeding iotlb entries
transparently.

Signed-off-by: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
Tested-by: Hari Kanigeri <h-kanigeri2@ti.com>

1 files changed, 31 insertions, 27 deletions

diff --git a/arch/arm/plat-omap/iommu.c b/arch/arm/plat-omap/iommu.c
index 1e83facb6b77..9598d40e2763 100644
--- a/arch/arm/plat-omap/iommu.c
+++ b/arch/arm/plat-omap/iommu.c
@@ -25,6 +25,11 @@
 
 #include "iopgtable.h"
 
+#define for_each_iotlb_cr(obj, n, __i, cr)                              \
+        for (__i = 0;                                                   \
+             (__i < (n)) && (cr = __iotlb_read_cr((obj), __i), true);   \
+             __i++)
+
 /* accommodate the difference between omap1 and omap2/3 */
 static const struct iommu_functions *arch_iommu;
 
@@ -211,6 +216,20 @@ static inline ssize_t iotlb_dump_cr(struct iommu *obj, struct cr_regs *cr,
         return arch_iommu->dump_cr(obj, cr, buf);
 }
 
+/* only used in iotlb iteration for-loop */
+static struct cr_regs __iotlb_read_cr(struct iommu *obj, int n)
+{
+        struct cr_regs cr;
+        struct iotlb_lock l;
+
+        iotlb_lock_get(obj, &l);
+        l.vict = n;
+        iotlb_lock_set(obj, &l);
+        iotlb_read_cr(obj, &cr);
+
+        return cr;
+}
+
 /**
  * load_iotlb_entry - Set an iommu tlb entry
  * @obj:        target iommu
@@ -218,7 +237,6 @@ static inline ssize_t iotlb_dump_cr(struct iommu *obj, struct cr_regs *cr,
  **/
 int load_iotlb_entry(struct iommu *obj, struct iotlb_entry *e)
 {
-        int i;
         int err = 0;
         struct iotlb_lock l;
         struct cr_regs *cr;
@@ -235,21 +253,20 @@ int load_iotlb_entry(struct iommu *obj, struct iotlb_entry *e)
                 goto out;
         }
         if (!e->prsvd) {
-                for (i = l.base; i < obj->nr_tlb_entries; i++) {
-                        struct cr_regs tmp;
+                int i;
+                struct cr_regs tmp;
 
-                        iotlb_lock_get(obj, &l);
-                        l.vict = i;
-                        iotlb_lock_set(obj, &l);
-                        iotlb_read_cr(obj, &tmp);
+                for_each_iotlb_cr(obj, obj->nr_tlb_entries, i, tmp)
                         if (!iotlb_cr_valid(&tmp))
                                 break;
-                }
+
                 if (i == obj->nr_tlb_entries) {
                         dev_dbg(obj->dev, "%s: full: no entry\n", __func__);
                         err = -EBUSY;
                         goto out;
                 }
+
+                iotlb_lock_get(obj, &l);
         } else {
                 l.vict = l.base;
                 iotlb_lock_set(obj, &l);
@@ -285,20 +302,15 @@ EXPORT_SYMBOL_GPL(load_iotlb_entry);
  **/
 void flush_iotlb_page(struct iommu *obj, u32 da)
 {
-        struct iotlb_lock l;
         int i;
+        struct cr_regs cr;
 
         clk_enable(obj->clk);
 
-        for (i = 0; i < obj->nr_tlb_entries; i++) {
-                struct cr_regs cr;
+        for_each_iotlb_cr(obj, obj->nr_tlb_entries, i, cr) {
                 u32 start;
                 size_t bytes;
 
-                iotlb_lock_get(obj, &l);
-                l.vict = i;
-                iotlb_lock_set(obj, &l);
-                iotlb_read_cr(obj, &cr);
                 if (!iotlb_cr_valid(&cr))
                         continue;
 
@@ -308,7 +320,6 @@ void flush_iotlb_page(struct iommu *obj, u32 da)
                 if ((start <= da) && (da < start + bytes)) {
                         dev_dbg(obj->dev, "%s: %08x<=%08x(%x)\n",
                                 __func__, start, da, bytes);
-                        iotlb_load_cr(obj, &cr);
                         iommu_write_reg(obj, 1, MMU_FLUSH_ENTRY);
                 }
         }
@@ -379,26 +390,19 @@ EXPORT_SYMBOL_GPL(iommu_dump_ctx);
 static int __dump_tlb_entries(struct iommu *obj, struct cr_regs *crs, int num)
 {
         int i;
-        struct iotlb_lock saved, l;
+        struct iotlb_lock saved;
+        struct cr_regs tmp;
         struct cr_regs *p = crs;
 
         clk_enable(obj->clk);
-
         iotlb_lock_get(obj, &saved);
-        memcpy(&l, &saved, sizeof(saved));
 
-        for (i = 0; i < num; i++) {
-                struct cr_regs tmp;
-
-                iotlb_lock_get(obj, &l);
-                l.vict = i;
-                iotlb_lock_set(obj, &l);
-                iotlb_read_cr(obj, &tmp);
+        for_each_iotlb_cr(obj, num, i, tmp) {
                 if (!iotlb_cr_valid(&tmp))
                         continue;
-
                 *p++ = tmp;
         }
+
         iotlb_lock_set(obj, &saved);
         clk_disable(obj->clk);