Hi, Here's a patch to introduce a DMI-based SSC frequency selection in intel_bios.c. Instead of always selecting the "alternate" SSC frequency as default during initialization, this patch lets some systems have the non-alternate frequency by default.
Thanks, Simon ===================================================== drivers: i915: Select non-alternate SSC frequency for some systems When initializing VBT default values, the alternate BIOS SSC frequency is selected. This patch allows the non-alternate frequency to be selected as a default, for specified systems. There is a DMI match list for systems that are to use the non-alternate frequency. Currently, only Lumpy is on the list. Signed-off-by: Simon Que <[email protected]> --- drivers/gpu/drm/i915/intel_bios.c | 17 ++++++++++++++++- 1 files changed, 16 insertions(+), 1 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_bios.c b/drivers/gpu/drm/i915/intel_bios.c index 927442a..ec75f15 100644 --- a/drivers/gpu/drm/i915/intel_bios.c +++ b/drivers/gpu/drm/i915/intel_bios.c @@ -25,6 +25,7 @@ * */ #include <drm/drm_dp_helper.h> +#include <linux/dmi.h> #include "drmP.h" #include "drm.h" #include "i915_drm.h" @@ -565,6 +566,17 @@ parse_device_mapping(struct drm_i915_private *dev_priv, return; } +static const struct dmi_system_id lvds_do_not_use_alternate_frequency[] = { + { + .callback = NULL, + .ident = "Lumpy", + .matches = { + DMI_MATCH(DMI_PRODUCT_NAME, "Lumpy"), + } + }, + { } +}; + static void init_vbt_defaults(struct drm_i915_private *dev_priv) { @@ -585,7 +597,10 @@ init_vbt_defaults(struct drm_i915_private *dev_priv) /* Default to using SSC */ dev_priv->lvds_use_ssc = 1; - dev_priv->lvds_ssc_freq = intel_bios_ssc_frequency(dev, 1); + if (dmi_check_system(lvds_do_not_use_alternate_frequency)) + dev_priv->lvds_ssc_freq = intel_bios_ssc_frequency(dev, 0); + else + dev_priv->lvds_ssc_freq = intel_bios_ssc_frequency(dev, 1); DRM_DEBUG("Set default to SSC at %dMHz\n", dev_priv->lvds_ssc_freq); /* eDP data */ -- 1.7.2.3 _______________________________________________ Intel-gfx mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/intel-gfx
