diff options
| author | Jesse Barnes <jbarnes@virtuousgeek.org> | 2010-01-14 20:48:02 +0000 |
|---|---|---|
| committer | Eric Anholt <eric@anholt.net> | 2010-01-15 14:08:01 -0800 |
| commit | 33814341f22f13cec17e8d7fbf6f7e8000e3efa4 (patch) | |
| tree | 7f43f096589e6900fb11db0033d3e68086d7c475 | |
| parent | 21bd770b9c90ee6a53a9dbb6293513a8c7654cfe (diff) | |
drm/i915: disable LVDS downclock by default
Many platform support this feature, and it can provide significant
power savings when the reduced refresh rate is low. However, on some
platforms a secondary (reduced) timing is provided but not actually
supported by the hardware. This results in undesirable flicker at
runtime.
So disable the feature by default, but allow users to opt-in to the
reduced clock behavior with a new module parameter, lvds_downclock,
that can be set to 1 to enable the feature.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
| -rw-r--r-- | drivers/gpu/drm/i915/i915_drv.c | 3 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/i915_drv.h | 1 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/intel_bios.c | 3 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/intel_lvds.c | 3 |
4 files changed, 8 insertions, 2 deletions
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c index 66f7bac2ee55..46d88965852a 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -45,6 +45,9 @@ module_param_named(fbpercrtc, i915_fbpercrtc, int, 0400); unsigned int i915_powersave = 1; module_param_named(powersave, i915_powersave, int, 0400); +unsigned int i915_lvds_downclock = 0; +module_param_named(lvds_downclock, i915_lvds_downclock, int, 0400); + static struct drm_driver driver; #define INTEL_VGA_DEVICE(id, info) { \ diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 445c49c6c397..5f781a74bf52 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -722,6 +722,7 @@ extern struct drm_ioctl_desc i915_ioctls[]; extern int i915_max_ioctl; extern unsigned int i915_fbpercrtc; extern unsigned int i915_powersave; +extern unsigned int i915_lvds_downclock; extern void i915_save_display(struct drm_device *dev); extern void i915_restore_display(struct drm_device *dev); diff --git a/drivers/gpu/drm/i915/intel_bios.c b/drivers/gpu/drm/i915/intel_bios.c index f27567747580..b53c46f202f6 100644 --- a/drivers/gpu/drm/i915/intel_bios.c +++ b/drivers/gpu/drm/i915/intel_bios.c @@ -197,7 +197,8 @@ parse_lfp_panel_data(struct drm_i915_private *dev_priv, memset(temp_mode, 0, sizeof(*temp_mode)); } kfree(temp_mode); - if (temp_downclock < panel_fixed_mode->clock) { + if (temp_downclock < panel_fixed_mode->clock && + i915_lvds_downclock) { dev_priv->lvds_downclock_avail = 1; dev_priv->lvds_downclock = temp_downclock; DRM_DEBUG_KMS("LVDS downclock is found in VBT. ", diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c index 5041590dfdc6..aa74e59bec61 100644 --- a/drivers/gpu/drm/i915/intel_lvds.c +++ b/drivers/gpu/drm/i915/intel_lvds.c @@ -926,7 +926,8 @@ static void intel_find_lvds_downclock(struct drm_device *dev, } } mutex_unlock(&dev->mode_config.mutex); - if (temp_downclock < panel_fixed_mode->clock) { + if (temp_downclock < panel_fixed_mode->clock && + i915_lvds_downclock) { /* We found the downclock for LVDS. */ dev_priv->lvds_downclock_avail = 1; dev_priv->lvds_downclock = temp_downclock; |