drm/i915: Allow frame buffers up to 4096x4096 on 915/945 class hardware

The 915 and 945 scanout engines can handle frame buffers up to 4096 pixels
wide. Pre-9xx hardware has an 8192 byte stride limit, and so we leave the
existing 2048 max in place.

I'm not sure why we limit the height to the same value; there's no intrinsic
hardware limit in the scanout engine.

Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Eric Anholt <eric@anholt.net>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 3371cb0ba81b..984645e26a2d 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -3148,6 +3148,9 @@ void intel_modeset_init(struct drm_device *dev)
         if (IS_I965G(dev)) {
                 dev->mode_config.max_width = 8192;
                 dev->mode_config.max_height = 8192;
+        } else if (IS_I9XX(dev)) {
+                dev->mode_config.max_width = 4096;
+                dev->mode_config.max_height = 4096;
         } else {
                 dev->mode_config.max_width = 2048;
                 dev->mode_config.max_height = 2048;