Add support to turn writeback off via radeon module option

diff --git a/bsd-core/radeon_drv.c b/bsd-core/radeon_drv.c
index bd59db6..470b6d3 100644 (file)
--- a/bsd-core/radeon_drv.c
+++ b/bsd-core/radeon_drv.c
@@ -35,6 +35,8 @@
 #include "radeon_drv.h"
 #include "drm_pciids.h"
 
+int radeon_no_wb;
+
 /* drv_PCI_IDs comes from drm_pciids.h, generated from drm_pciids.txt. */
 static drm_pci_id_list_t radeon_pciidlist[] = {
        radeon_PCI_IDS

diff --git a/linux-core/radeon_drv.c b/linux-core/radeon_drv.c
index 41ca7ac..52e5017 100644 (file)
--- a/linux-core/radeon_drv.c
+++ b/linux-core/radeon_drv.c
@@ -37,6 +37,10 @@
 
 #include "drm_pciids.h"
 
+int radeon_no_wb;
+
+MODULE_PARM_DESC(no_wb, "Disable AGP writeback for scratch registers\n");
+module_param_named(no_wb, radeon_no_wb, int, 0444);
 
 static int dri_library_name(struct drm_device * dev, char * buf)
 {

diff --git a/shared-core/radeon_cp.c b/shared-core/radeon_cp.c
index f3c5ecf..9b5c9a8 100644 (file)
--- a/shared-core/radeon_cp.c
+++ b/shared-core/radeon_cp.c
@@ -1206,6 +1206,10 @@ static void radeon_cp_init_ring_buffer(drm_device_t * dev,
                dev_priv->writeback_works = 0;
                DRM_DEBUG("writeback test failed\n");
        }
+       if (radeon_no_wb == 1) {
+               dev_priv->writeback_works = 0;
+               DRM_DEBUG("writeback forced off\n");
+       }
 
        dev_priv->sarea_priv->last_frame = dev_priv->scratch[0] = 0;
        RADEON_WRITE(RADEON_LAST_FRAME_REG, dev_priv->sarea_priv->last_frame);

diff --git a/shared-core/radeon_drv.h b/shared-core/radeon_drv.h
index 265697c..8455d59 100644 (file)
--- a/shared-core/radeon_drv.h
+++ b/shared-core/radeon_drv.h
@@ -275,6 +275,7 @@ typedef struct drm_radeon_buf_priv {
        u32 age;
 } drm_radeon_buf_priv_t;
 
+extern int radeon_no_wb;
                                /* radeon_cp.c */
 extern int radeon_cp_init(DRM_IOCTL_ARGS);
 extern int radeon_cp_start(DRM_IOCTL_ARGS);