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b0b3384612
Normmally the common lane in a PHY channel gets powered up when some of the data lanes get powered up. But when we're driving port B with pipe B we don't want to enabled any of the data lanes, and just want the DPLL in the common lane to be active. To make that happens we have to temporarily enable some data lanes after which we can access the DPLL registers in the common lane. Once the pipe is up and running we can drop the power override on the data lanes allowing them to shut down. From this point forward the common lane will in fact stay powered on until the data lanes in the other channel get powered down. Ville's extended explanation from the review thread: On Wed, Aug 19, 2015 at 07:47:41AM +0530, Deepak wrote: > One Q, why only for port B? Port C is also in same common lane right? Port B is in the first PHY channel which also houses CL1. CL1 always powers up whenever any lanes in either PHY channel are powered up. CL2 only powers up if lanes in the second channel (ie. the one with port C) powers up. So in this scenario (pipe B->port B) we want the DPLL from CL2, but ideally we only want to power up the lanes for port B. Powering up port B lanes will only power up CL1, but as we need CL2 instead we need to, temporarily, power up some lanes in port C as well. Crossing the streams the other way (pipe A->port C) is not a problem since CL1 powers up whenever anything else powers up. So powering up some port C lanes is enough on its own to make the CL1 DPLL operational, even though CL1 and the lanes live in separate channels. Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Deepak S <deepak.s@linux.intel.com> [danvet: Amend commit message with extended explanation.] Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> |
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| amd | ||
| armada | ||
| ast | ||
| atmel-hlcdc | ||
| bochs | ||
| bridge | ||
| cirrus | ||
| exynos | ||
| gma500 | ||
| i2c | ||
| i810 | ||
| i915 | ||
| imx | ||
| mga | ||
| mgag200 | ||
| msm | ||
| nouveau | ||
| omapdrm | ||
| panel | ||
| qxl | ||
| r128 | ||
| radeon | ||
| rcar-du | ||
| rockchip | ||
| savage | ||
| shmobile | ||
| sis | ||
| sti | ||
| tdfx | ||
| tegra | ||
| tilcdc | ||
| ttm | ||
| udl | ||
| vgem | ||
| via | ||
| virtio | ||
| vmwgfx | ||
| ati_pcigart.c | ||
| drm_agpsupport.c | ||
| drm_atomic_helper.c | ||
| drm_atomic.c | ||
| drm_auth.c | ||
| drm_bridge.c | ||
| drm_bufs.c | ||
| drm_cache.c | ||
| drm_context.c | ||
| drm_crtc_helper.c | ||
| drm_crtc_internal.h | ||
| drm_crtc.c | ||
| drm_debugfs.c | ||
| drm_dma.c | ||
| drm_dp_helper.c | ||
| drm_dp_mst_topology.c | ||
| drm_drv.c | ||
| drm_edid_load.c | ||
| drm_edid.c | ||
| drm_encoder_slave.c | ||
| drm_fb_cma_helper.c | ||
| drm_fb_helper.c | ||
| drm_flip_work.c | ||
| drm_fops.c | ||
| drm_gem_cma_helper.c | ||
| drm_gem.c | ||
| drm_global.c | ||
| drm_hashtab.c | ||
| drm_info.c | ||
| drm_internal.h | ||
| drm_ioc32.c | ||
| drm_ioctl.c | ||
| drm_irq.c | ||
| drm_legacy.h | ||
| drm_lock.c | ||
| drm_memory.c | ||
| drm_mipi_dsi.c | ||
| drm_mm.c | ||
| drm_modes.c | ||
| drm_modeset_lock.c | ||
| drm_of.c | ||
| drm_panel.c | ||
| drm_pci.c | ||
| drm_plane_helper.c | ||
| drm_platform.c | ||
| drm_prime.c | ||
| drm_probe_helper.c | ||
| drm_rect.c | ||
| drm_scatter.c | ||
| drm_sysfs.c | ||
| drm_trace_points.c | ||
| drm_trace.h | ||
| drm_vm.c | ||
| drm_vma_manager.c | ||
| Kconfig | ||
| Makefile | ||