agp/uninorth: Simplify cache flushing.

Map the GART table uncached, so we don't always need to flush the CPU caches
explicitly after updates.

Signed-off-by: Michel Dänzer <daenzer@vmware.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 25 insertions, 8 deletions

diff --git a/drivers/char/agp/uninorth-agp.c b/drivers/char/agp/uninorth-agp.c
index 37ff3bd56d60..bba29abe917f 100644
--- a/drivers/char/agp/uninorth-agp.c
+++ b/drivers/char/agp/uninorth-agp.c
@@ -7,6 +7,7 @@
 #include <linux/pagemap.h>
 #include <linux/agp_backend.h>
 #include <linux/delay.h>
+#include <linux/vmalloc.h>
 #include <asm/uninorth.h>
 #include <asm/pci-bridge.h>
 #include <asm/prom.h>
@@ -181,8 +182,6 @@ static int uninorth_insert_memory(struct agp_memory *mem, off_t pg_start,
         }
         (void)in_le32((volatile u32*)&agp_bridge->gatt_table[pg_start]);
         mb();
-        flush_dcache_range((unsigned long)&agp_bridge->gatt_table[pg_start],
-                (unsigned long)&agp_bridge->gatt_table[pg_start + mem->page_count]);
 
         uninorth_tlbflush(mem);
         return 0;
@@ -226,7 +225,6 @@ static int u3_insert_memory(struct agp_memory *mem, off_t pg_start, int type)
                                    (unsigned long)__va(page_to_phys(mem->pages[i]))+0x1000);
         }
         mb();
-        flush_dcache_range((unsigned long)gp, (unsigned long) &gp[i]);
         uninorth_tlbflush(mem);
 
         return 0;
@@ -245,7 +243,6 @@ int u3_remove_memory(struct agp_memory *mem, off_t pg_start, int type)
         for (i = 0; i < mem->page_count; ++i)
                 gp[i] = 0;
         mb();
-        flush_dcache_range((unsigned long)gp, (unsigned long) &gp[i]);
         uninorth_tlbflush(mem);
 
         return 0;
@@ -398,6 +395,7 @@ static int uninorth_create_gatt_table(struct agp_bridge_data *bridge)
         int i;
         void *temp;
         struct page *page;
+        struct page **pages;
 
         /* We can't handle 2 level gatt's */
         if (bridge->driver->size_type == LVL2_APER_SIZE)
@@ -426,21 +424,39 @@ static int uninorth_create_gatt_table(struct agp_bridge_data *bridge)
         if (table == NULL)
                 return -ENOMEM;
 
+        pages = kmalloc((1 << page_order) * sizeof(struct page*), GFP_KERNEL);
+        if (pages == NULL)
+                goto enomem;
+
         table_end = table + ((PAGE_SIZE * (1 << page_order)) - 1);
 
-        for (page = virt_to_page(table); page <= virt_to_page(table_end); page++)
+        for (page = virt_to_page(table), i = 0; page <= virt_to_page(table_end);
+             page++, i++) {
                 SetPageReserved(page);
+                pages[i] = page;
+        }
 
         bridge->gatt_table_real = (u32 *) table;
-        bridge->gatt_table = (u32 *)table;
+        /* Need to clear out any dirty data still sitting in caches */
+        flush_dcache_range((unsigned long)table,
+                           (unsigned long)(table_end + PAGE_SIZE));
+        bridge->gatt_table = vmap(pages, (1 << page_order), 0, PAGE_KERNEL_NCG);
+
+        if (bridge->gatt_table == NULL)
+                goto enomem;
+
         bridge->gatt_bus_addr = virt_to_gart(table);
 
         for (i = 0; i < num_entries; i++)
                 bridge->gatt_table[i] = 0;
 
-        flush_dcache_range((unsigned long)table, (unsigned long)table_end);
-
         return 0;
+
+enomem:
+        kfree(pages);
+        if (table)
+                free_pages((unsigned long)table, page_order);
+        return -ENOMEM;
 }
 
 static int uninorth_free_gatt_table(struct agp_bridge_data *bridge)
@@ -458,6 +474,7 @@ static int uninorth_free_gatt_table(struct agp_bridge_data *bridge)
          * from the table.
          */
 
+        vunmap(bridge->gatt_table);
         table = (char *) bridge->gatt_table_real;
         table_end = table + ((PAGE_SIZE * (1 << page_order)) - 1);