2 files changed, 26 insertions, 35 deletions

diff --git a/drivers/media/pci/ivtv/Kconfig b/drivers/media/pci/ivtv/Kconfig
index dd6ee57e3a4c..6e5867c57305 100644
--- a/drivers/media/pci/ivtv/Kconfig
+++ b/drivers/media/pci/ivtv/Kconfig
@@ -57,5 +57,8 @@ config VIDEO_FB_IVTV
           This is used in the Hauppauge PVR-350 card. There is a driver
           homepage at <http://www.ivtvdriver.org>.
 
+          In order to use this module, you will need to boot with PAT disabled
+          on x86 systems, using the nopat kernel parameter.
+
           To compile this driver as a module, choose M here: the
           module will be called ivtvfb.
diff --git a/drivers/media/pci/ivtv/ivtvfb.c b/drivers/media/pci/ivtv/ivtvfb.c
index 9ff1230192e8..4cb365d4ffdc 100644
--- a/drivers/media/pci/ivtv/ivtvfb.c
+++ b/drivers/media/pci/ivtv/ivtvfb.c
@@ -44,8 +44,8 @@
 #include <linux/ivtvfb.h>
 #include <linux/slab.h>
 
-#ifdef CONFIG_MTRR
-#include <asm/mtrr.h>
+#ifdef CONFIG_X86_64
+#include <asm/pat.h>
 #endif
 
 #include "ivtv-driver.h"
@@ -155,12 +155,11 @@ struct osd_info {
         /* Buffer size */
         u32 video_buffer_size;
 
-#ifdef CONFIG_MTRR
         /* video_base rounded down as required by hardware MTRRs */
         unsigned long fb_start_aligned_physaddr;
         /* video_base rounded up as required by hardware MTRRs */
         unsigned long fb_end_aligned_physaddr;
-#endif
+        int wc_cookie;
 
         /* Store the buffer offset */
         int set_osd_coords_x;
@@ -1099,6 +1098,8 @@ static int ivtvfb_init_vidmode(struct ivtv *itv)
 static int ivtvfb_init_io(struct ivtv *itv)
 {
         struct osd_info *oi = itv->osd_info;
+        /* Find the largest power of two that maps the whole buffer */
+        int size_shift = 31;
 
         mutex_lock(&itv->serialize_lock);
         if (ivtv_init_on_first_open(itv)) {
@@ -1132,29 +1133,16 @@ static int ivtvfb_init_io(struct ivtv *itv)
                         oi->video_pbase, oi->video_vbase,
                         oi->video_buffer_size / 1024);
 
-#ifdef CONFIG_MTRR
-        {
-                /* Find the largest power of two that maps the whole buffer */
-                int size_shift = 31;
-
-                while (!(oi->video_buffer_size & (1 << size_shift))) {
-                        size_shift--;
-                }
-                size_shift++;
-                oi->fb_start_aligned_physaddr = oi->video_pbase & ~((1 << size_shift) - 1);
-                oi->fb_end_aligned_physaddr = oi->video_pbase + oi->video_buffer_size;
-                oi->fb_end_aligned_physaddr += (1 << size_shift) - 1;
-                oi->fb_end_aligned_physaddr &= ~((1 << size_shift) - 1);
-                if (mtrr_add(oi->fb_start_aligned_physaddr,
-                        oi->fb_end_aligned_physaddr - oi->fb_start_aligned_physaddr,
-                             MTRR_TYPE_WRCOMB, 1) < 0) {
-                        IVTVFB_INFO("disabled mttr\n");
-                        oi->fb_start_aligned_physaddr = 0;
-                        oi->fb_end_aligned_physaddr = 0;
-                }
-        }
-#endif
-
+        while (!(oi->video_buffer_size & (1 << size_shift)))
+                size_shift--;
+        size_shift++;
+        oi->fb_start_aligned_physaddr = oi->video_pbase & ~((1 << size_shift) - 1);
+        oi->fb_end_aligned_physaddr = oi->video_pbase + oi->video_buffer_size;
+        oi->fb_end_aligned_physaddr += (1 << size_shift) - 1;
+        oi->fb_end_aligned_physaddr &= ~((1 << size_shift) - 1);
+        oi->wc_cookie = arch_phys_wc_add(oi->fb_start_aligned_physaddr,
+                                         oi->fb_end_aligned_physaddr -
+                                         oi->fb_start_aligned_physaddr);
         /* Blank the entire osd. */
         memset_io(oi->video_vbase, 0, oi->video_buffer_size);
 
@@ -1172,14 +1160,7 @@ static void ivtvfb_release_buffers (struct ivtv *itv)
 
         /* Release pseudo palette */
         kfree(oi->ivtvfb_info.pseudo_palette);
-
-#ifdef CONFIG_MTRR
-        if (oi->fb_end_aligned_physaddr) {
-                mtrr_del(-1, oi->fb_start_aligned_physaddr,
-                        oi->fb_end_aligned_physaddr - oi->fb_start_aligned_physaddr);
-        }
-#endif
-
+        arch_phys_wc_del(oi->wc_cookie);
         kfree(oi);
         itv->osd_info = NULL;
 }
@@ -1284,6 +1265,13 @@ static int __init ivtvfb_init(void)
         int registered = 0;
         int err;
 
+#ifdef CONFIG_X86_64
+        if (WARN(pat_enabled(),
+                 "ivtvfb needs PAT disabled, boot with nopat kernel parameter\n")) {
+                return -ENODEV;
+        }
+#endif
+
         if (ivtvfb_card_id < -1 || ivtvfb_card_id >= IVTV_MAX_CARDS) {
                 printk(KERN_ERR "ivtvfb:  ivtvfb_card_id parameter is out of range (valid range: -1 - %d)\n",
                      IVTV_MAX_CARDS - 1);