From: Mahesh Kumar <mahesh1.kumar@xxxxxxxxx> This patch adds IPC support for platforms. This patch enables IPC only for BXT/KBL platform as for SKL recommendation is to keep is disabled. IPC (Isochronous Priority Control) is the hardware feature, which dynamically controles the memory read priority of Display. When IPC is enabled, plane read requests are sent at high priority until filling above the transition watermark, then the requests are sent at lower priority until dropping below the level 0 watermark. The lower priority requests allow other memory clients to have better memory access. When IPC is disabled, all plane read requests are sent at high priority. Changes since V1: - Remove commandline parameter to disable ipc - Address Paulo's comments Signed-off-by: Mahesh Kumar <mahesh1.kumar@xxxxxxxxx> --- drivers/gpu/drm/i915/i915_drv.c | 2 ++ drivers/gpu/drm/i915/i915_reg.h | 1 + drivers/gpu/drm/i915/intel_drv.h | 1 + drivers/gpu/drm/i915/intel_pm.c | 15 +++++++++++++++ 4 files changed, 19 insertions(+) diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c index b5f601c..58abbaa 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -1415,6 +1415,8 @@ int i915_driver_load(struct pci_dev *pdev, const struct pci_device_id *ent) intel_runtime_pm_enable(dev_priv); + intel_enable_ipc(dev_priv); + /* Everything is in place, we can now relax! */ DRM_INFO("Initialized %s %d.%d.%d %s for %s on minor %d\n", driver.name, driver.major, driver.minor, driver.patchlevel, diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index a9c467c..c9ebf23 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -6144,6 +6144,7 @@ enum { #define DISP_FBC_WM_DIS (1<<15) #define DISP_ARB_CTL2 _MMIO(0x45004) #define DISP_DATA_PARTITION_5_6 (1<<6) +#define DISP_IPC_ENABLE (1<<3) #define DBUF_CTL _MMIO(0x45008) #define DBUF_POWER_REQUEST (1<<31) #define DBUF_POWER_STATE (1<<30) diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index 2c1897b..45b0fa4 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -1766,6 +1766,7 @@ void skl_write_plane_wm(struct intel_crtc *intel_crtc, uint32_t ilk_pipe_pixel_rate(const struct intel_crtc_state *pipe_config); bool ilk_disable_lp_wm(struct drm_device *dev); int sanitize_rc6_option(struct drm_i915_private *dev_priv, int enable_rc6); +void intel_enable_ipc(struct drm_i915_private *dev_priv); static inline int intel_enable_rc6(void) { return i915.enable_rc6; diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 4263212..543aa5d 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -4833,6 +4833,21 @@ void intel_update_watermarks(struct drm_crtc *crtc) dev_priv->display.update_wm(crtc); } +void intel_enable_ipc(struct drm_i915_private *dev_priv) +{ + u32 val; + + /* enable IPC only for Broxton for now*/ + if (!IS_BROXTON(dev_priv) || !IS_KABYLAKE(dev_priv)) + return; + + val = I915_READ(DISP_ARB_CTL2); + + val |= DISP_IPC_ENABLE; + + I915_WRITE(DISP_ARB_CTL2, val); +} + /* * Lock protecting IPS related data structures */ -- 2.10.1 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx