From ffe74d75502e3a9b0791240b5562bcbecc6ab8dc Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Mon, 26 Aug 2013 20:58:12 +0100 Subject: [PATCH] drm/i915: Use RCS flips on Ivybridge+ MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit RCS flips do work on Iybridge+ so long as we can unmask the messages through DERRMR. However, there are quite a few workarounds mentioned regarding unmasking more than one event or triggering more than one message through DERRMR. Those workarounds in principle prevent us from performing pipelined flips (and asynchronous flips across multiple planes) and equally apply to the "known good" BCS ring. Given that it already appears to work, and also appears to work with unmasking all 3 planes at once (and queuing flips across multiple planes), be brave. Bugzlla: https://bugs.freedesktop.org/show_bug.cgi?id=67600 Signed-off-by: Chris Wilson Lightly-tested-by: Stephane Marchesin Cc: Stephane Marchesin Cc: Ben Widawsky Tested-by: Stéphane Marchesin Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/i915_reg.h | 18 ++++++++++++++++ drivers/gpu/drm/i915/intel_display.c | 40 ++++++++++++++++++++++++++++-------- 2 files changed, 49 insertions(+), 9 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index b6a58f7..b2fa2a4 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -245,6 +245,7 @@ * address/value pairs. Don't overdue it, though, x <= 2^4 must hold! */ #define MI_LOAD_REGISTER_IMM(x) MI_INSTR(0x22, 2*x-1) +#define MI_STORE_REGISTER_MEM(x) MI_INSTR(0x24, 2*x-1) #define MI_FLUSH_DW MI_INSTR(0x26, 1) /* for GEN6 */ #define MI_FLUSH_DW_STORE_INDEX (1<<21) #define MI_INVALIDATE_TLB (1<<18) @@ -693,6 +694,23 @@ #define FPGA_DBG_RM_NOCLAIM (1<<31) #define DERRMR 0x44050 +#define DERRMR_PIPEA_SCANLINE (1<<0) +#define DERRMR_PIPEA_PRI_FLIP_DONE (1<<1) +#define DERRMR_PIPEA_SPR_FLIP_DONE (1<<2) +#define DERRMR_PIPEA_VBLANK (1<<3) +#define DERRMR_PIPEA_HBLANK (1<<5) +#define DERRMR_PIPEB_SCANLINE (1<<8) +#define DERRMR_PIPEB_PRI_FLIP_DONE (1<<9) +#define DERRMR_PIPEB_SPR_FLIP_DONE (1<<10) +#define DERRMR_PIPEB_VBLANK (1<<11) +#define DERRMR_PIPEB_HBLANK (1<<13) +/* Note that PIPEC is not a simple translation of PIPEA/PIPEB */ +#define DERRMR_PIPEC_SCANLINE (1<<14) +#define DERRMR_PIPEC_PRI_FLIP_DONE (1<<15) +#define DERRMR_PIPEC_SPR_FLIP_DONE (1<<20) +#define DERRMR_PIPEC_VBLANK (1<<21) +#define DERRMR_PIPEC_HBLANK (1<<22) + /* GM45+ chicken bits -- debug workaround bits that may be required * for various sorts of correct behavior. The top 16 bits of each are diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 38452d8..a98392f 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -7828,12 +7828,6 @@ err: return ret; } -/* - * On gen7 we currently use the blit ring because (in early silicon at least) - * the render ring doesn't give us interrpts for page flip completion, which - * means clients will hang after the first flip is queued. Fortunately the - * blit ring generates interrupts properly, so use it instead. - */ static int intel_gen7_queue_flip(struct drm_device *dev, struct drm_crtc *crtc, struct drm_framebuffer *fb, @@ -7842,9 +7836,13 @@ static int intel_gen7_queue_flip(struct drm_device *dev, { struct drm_i915_private *dev_priv = dev->dev_private; struct intel_crtc *intel_crtc = to_intel_crtc(crtc); - struct intel_ring_buffer *ring = &dev_priv->ring[BCS]; + struct intel_ring_buffer *ring; uint32_t plane_bit = 0; - int ret; + int len, ret; + + ring = obj->ring; + if (ring == NULL || ring->id != RCS) + ring = &dev_priv->ring[BCS]; ret = intel_pin_and_fence_fb_obj(dev, obj, ring); if (ret) @@ -7866,10 +7864,34 @@ static int intel_gen7_queue_flip(struct drm_device *dev, goto err_unpin; } - ret = intel_ring_begin(ring, 4); + len = 4; + if (ring->id == RCS) + len += 6; + + ret = intel_ring_begin(ring, len); if (ret) goto err_unpin; + /* Unmask the flip-done completion message. Note that the bspec says that + * we should do this for both the BCS and RCS, and that we must not unmask + * more than one flip event at any time (or ensure that one flip message + * can be sent by waiting for flip-done prior to queueing new flips). + * Experimentation says that BCS works despite DERRMR masking all + * flip-done completion events and that unmasking all planes at once + * for the RCS also doesn't appear to drop events. Setting the DERRMR + * to zero does lead to lockups within MI_DISPLAY_FLIP. + */ + if (ring->id == RCS) { + intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(1)); + intel_ring_emit(ring, DERRMR); + intel_ring_emit(ring, ~(DERRMR_PIPEA_PRI_FLIP_DONE | + DERRMR_PIPEB_PRI_FLIP_DONE | + DERRMR_PIPEC_PRI_FLIP_DONE)); + intel_ring_emit(ring, MI_STORE_REGISTER_MEM(1)); + intel_ring_emit(ring, DERRMR); + intel_ring_emit(ring, ring->scratch.gtt_offset + 256); + } + intel_ring_emit(ring, MI_DISPLAY_FLIP_I915 | plane_bit); intel_ring_emit(ring, (fb->pitches[0] | obj->tiling_mode)); intel_ring_emit(ring, i915_gem_obj_ggtt_offset(obj) + intel_crtc->dspaddr_offset); -- 2.7.4