drm/radeon/kms/atom: add support for spread spectrum (v2)
Spread spectrum is a periodic disturbance added
to the feedback divider to change the pixel clock
periodically to reduce interference.
Only enabled on LVDS.
v2: add support for r4xx and fix DCE 3
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/radeon_atombios.c b/drivers/gpu/drm/radeon/radeon_atombios.c
index cec6791..1872925 100644
--- a/drivers/gpu/drm/radeon/radeon_atombios.c
+++ b/drivers/gpu/drm/radeon/radeon_atombios.c
@@ -771,6 +771,46 @@
return false;
}
+static struct radeon_atom_ss *radeon_atombios_get_ss_info(struct
+ radeon_encoder
+ *encoder,
+ int id)
+{
+ struct drm_device *dev = encoder->base.dev;
+ struct radeon_device *rdev = dev->dev_private;
+ struct radeon_mode_info *mode_info = &rdev->mode_info;
+ int index = GetIndexIntoMasterTable(DATA, PPLL_SS_Info);
+ uint16_t data_offset;
+ struct _ATOM_SPREAD_SPECTRUM_INFO *ss_info;
+ uint8_t frev, crev;
+ struct radeon_atom_ss *ss = NULL;
+
+ if (id > ATOM_MAX_SS_ENTRY)
+ return NULL;
+
+ atom_parse_data_header(mode_info->atom_context, index, NULL, &frev,
+ &crev, &data_offset);
+
+ ss_info =
+ (struct _ATOM_SPREAD_SPECTRUM_INFO *)(mode_info->atom_context->bios + data_offset);
+
+ if (ss_info) {
+ ss =
+ kzalloc(sizeof(struct radeon_atom_ss), GFP_KERNEL);
+
+ if (!ss)
+ return NULL;
+
+ ss->percentage = le16_to_cpu(ss_info->asSS_Info[id].usSpreadSpectrumPercentage);
+ ss->type = ss_info->asSS_Info[id].ucSpreadSpectrumType;
+ ss->step = ss_info->asSS_Info[id].ucSS_Step;
+ ss->delay = ss_info->asSS_Info[id].ucSS_Delay;
+ ss->range = ss_info->asSS_Info[id].ucSS_Range;
+ ss->refdiv = ss_info->asSS_Info[id].ucRecommendedRef_Div;
+ }
+ return ss;
+}
+
union lvds_info {
struct _ATOM_LVDS_INFO info;
struct _ATOM_LVDS_INFO_V12 info_12;
@@ -826,6 +866,8 @@
/* set crtc values */
drm_mode_set_crtcinfo(&lvds->native_mode, CRTC_INTERLACE_HALVE_V);
+ lvds->ss = radeon_atombios_get_ss_info(encoder, lvds_info->info.ucSS_Id);
+
encoder->native_mode = lvds->native_mode;
}
return lvds;