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* [PATCH] drm: kirin: Revert "Fix for hikey620 display offset problem"
@ 2020-03-03 16:32 John Stultz
  2020-03-04  9:28 ` Xinliang Liu
  0 siblings, 1 reply; 4+ messages in thread
From: John Stultz @ 2020-03-03 16:32 UTC (permalink / raw)
  To: lkml
  Cc: John Stultz, Xinliang Liu, Rongrong Zou, Xinwei Kong, Chen Feng,
	Sam Ravnborg, David Airlie, Daniel Vetter, dri-devel

This reverts commit ff57c6513820efe945b61863cf4a51b79f18b592.

With the commit ff57c6513820 ("drm: kirin: Fix for hikey620
display offset problem") we added support for handling LDI
overflows by resetting the hardware.

However, its been observed that when we do hit the LDI overflow
condition, the irq seems to be screaming, and we do nothing but
stream:
  [drm:ade_irq_handler [kirin_drm]] *ERROR* LDI underflow!
over and over to the screen

I've tried a few appraoches to avoid this, but none has yet
been successful and the cure here is worse then the original
disease, so revert this for now.

Cc: Xinliang Liu <xinliang.liu@linaro.org>
Cc: Rongrong Zou <zourongrong@gmail.com>
Cc: Xinwei Kong <kong.kongxinwei@hisilicon.com>
Cc: Chen Feng <puck.chen@hisilicon.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel <dri-devel@lists.freedesktop.org>
Fixes: ff57c6513820 ("drm: kirin: Fix for hikey620 display offset problem")
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
 .../gpu/drm/hisilicon/kirin/kirin_ade_reg.h   |  1 -
 .../gpu/drm/hisilicon/kirin/kirin_drm_ade.c   | 20 -------------------
 2 files changed, 21 deletions(-)

diff --git a/drivers/gpu/drm/hisilicon/kirin/kirin_ade_reg.h b/drivers/gpu/drm/hisilicon/kirin/kirin_ade_reg.h
index 0da860200410..e2ac09894a6d 100644
--- a/drivers/gpu/drm/hisilicon/kirin/kirin_ade_reg.h
+++ b/drivers/gpu/drm/hisilicon/kirin/kirin_ade_reg.h
@@ -83,7 +83,6 @@
 #define VSIZE_OFST			20
 #define LDI_INT_EN			0x741C
 #define FRAME_END_INT_EN_OFST		1
-#define UNDERFLOW_INT_EN_OFST		2
 #define LDI_CTRL			0x7420
 #define BPP_OFST			3
 #define DATA_GATE_EN			BIT(2)
diff --git a/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c b/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c
index 73cd28a6ea07..86000127d4ee 100644
--- a/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c
+++ b/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c
@@ -46,7 +46,6 @@ struct ade_hw_ctx {
 	struct clk *media_noc_clk;
 	struct clk *ade_pix_clk;
 	struct reset_control *reset;
-	struct work_struct display_reset_wq;
 	bool power_on;
 	int irq;
 
@@ -136,7 +135,6 @@ static void ade_init(struct ade_hw_ctx *ctx)
 	 */
 	ade_update_bits(base + ADE_CTRL, FRM_END_START_OFST,
 			FRM_END_START_MASK, REG_EFFECTIVE_IN_ADEEN_FRMEND);
-	ade_update_bits(base + LDI_INT_EN, UNDERFLOW_INT_EN_OFST, MASK(1), 1);
 }
 
 static bool ade_crtc_mode_fixup(struct drm_crtc *crtc,
@@ -304,17 +302,6 @@ static void ade_crtc_disable_vblank(struct drm_crtc *crtc)
 			MASK(1), 0);
 }
 
-static void drm_underflow_wq(struct work_struct *work)
-{
-	struct ade_hw_ctx *ctx = container_of(work, struct ade_hw_ctx,
-					      display_reset_wq);
-	struct drm_device *drm_dev = ctx->crtc->dev;
-	struct drm_atomic_state *state;
-
-	state = drm_atomic_helper_suspend(drm_dev);
-	drm_atomic_helper_resume(drm_dev, state);
-}
-
 static irqreturn_t ade_irq_handler(int irq, void *data)
 {
 	struct ade_hw_ctx *ctx = data;
@@ -331,12 +318,6 @@ static irqreturn_t ade_irq_handler(int irq, void *data)
 				MASK(1), 1);
 		drm_crtc_handle_vblank(crtc);
 	}
-	if (status & BIT(UNDERFLOW_INT_EN_OFST)) {
-		ade_update_bits(base + LDI_INT_CLR, UNDERFLOW_INT_EN_OFST,
-				MASK(1), 1);
-		DRM_ERROR("LDI underflow!");
-		schedule_work(&ctx->display_reset_wq);
-	}
 
 	return IRQ_HANDLED;
 }
@@ -919,7 +900,6 @@ static void *ade_hw_ctx_alloc(struct platform_device *pdev,
 	if (ret)
 		return ERR_PTR(-EIO);
 
-	INIT_WORK(&ctx->display_reset_wq, drm_underflow_wq);
 	ctx->crtc = crtc;
 
 	return ctx;
-- 
2.17.1


^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH] drm: kirin: Revert "Fix for hikey620 display offset problem"
  2020-03-03 16:32 [PATCH] drm: kirin: Revert "Fix for hikey620 display offset problem" John Stultz
@ 2020-03-04  9:28 ` Xinliang Liu
  2020-03-04  9:32   ` Xinliang Liu
  0 siblings, 1 reply; 4+ messages in thread
From: Xinliang Liu @ 2020-03-04  9:28 UTC (permalink / raw)
  To: John Stultz
  Cc: lkml, Rongrong Zou, Xinwei Kong, Chen Feng, Sam Ravnborg,
	David Airlie, Daniel Vetter, dri-devel

On Wed, 4 Mar 2020 at 00:32, John Stultz <john.stultz@linaro.org> wrote:
>
> This reverts commit ff57c6513820efe945b61863cf4a51b79f18b592.
>
> With the commit ff57c6513820 ("drm: kirin: Fix for hikey620
> display offset problem") we added support for handling LDI
> overflows by resetting the hardware.
>
> However, its been observed that when we do hit the LDI overflow
> condition, the irq seems to be screaming, and we do nothing but
> stream:
>   [drm:ade_irq_handler [kirin_drm]] *ERROR* LDI underflow!
> over and over to the screen
>
> I've tried a few appraoches to avoid this, but none has yet
> been successful and the cure here is worse then the original
> disease, so revert this for now.

Sorry to hear that. Then it seems such underflow errors can't be
recovered via reset.
Anyway, for this patch
Acked-by: Xinliang Liu <z.liuxinliang@hisilicon.com>

And applied to drm-misc .

-xinliang

>
> Cc: Xinliang Liu <xinliang.liu@linaro.org>
> Cc: Rongrong Zou <zourongrong@gmail.com>
> Cc: Xinwei Kong <kong.kongxinwei@hisilicon.com>
> Cc: Chen Feng <puck.chen@hisilicon.com>
> Cc: Sam Ravnborg <sam@ravnborg.org>
> Cc: David Airlie <airlied@linux.ie>
> Cc: Daniel Vetter <daniel@ffwll.ch>
> Cc: dri-devel <dri-devel@lists.freedesktop.org>
> Fixes: ff57c6513820 ("drm: kirin: Fix for hikey620 display offset problem")
> Signed-off-by: John Stultz <john.stultz@linaro.org>
> ---
>  .../gpu/drm/hisilicon/kirin/kirin_ade_reg.h   |  1 -
>  .../gpu/drm/hisilicon/kirin/kirin_drm_ade.c   | 20 -------------------
>  2 files changed, 21 deletions(-)
>
> diff --git a/drivers/gpu/drm/hisilicon/kirin/kirin_ade_reg.h b/drivers/gpu/drm/hisilicon/kirin/kirin_ade_reg.h
> index 0da860200410..e2ac09894a6d 100644
> --- a/drivers/gpu/drm/hisilicon/kirin/kirin_ade_reg.h
> +++ b/drivers/gpu/drm/hisilicon/kirin/kirin_ade_reg.h
> @@ -83,7 +83,6 @@
>  #define VSIZE_OFST                     20
>  #define LDI_INT_EN                     0x741C
>  #define FRAME_END_INT_EN_OFST          1
> -#define UNDERFLOW_INT_EN_OFST          2
>  #define LDI_CTRL                       0x7420
>  #define BPP_OFST                       3
>  #define DATA_GATE_EN                   BIT(2)
> diff --git a/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c b/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c
> index 73cd28a6ea07..86000127d4ee 100644
> --- a/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c
> +++ b/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c
> @@ -46,7 +46,6 @@ struct ade_hw_ctx {
>         struct clk *media_noc_clk;
>         struct clk *ade_pix_clk;
>         struct reset_control *reset;
> -       struct work_struct display_reset_wq;
>         bool power_on;
>         int irq;
>
> @@ -136,7 +135,6 @@ static void ade_init(struct ade_hw_ctx *ctx)
>          */
>         ade_update_bits(base + ADE_CTRL, FRM_END_START_OFST,
>                         FRM_END_START_MASK, REG_EFFECTIVE_IN_ADEEN_FRMEND);
> -       ade_update_bits(base + LDI_INT_EN, UNDERFLOW_INT_EN_OFST, MASK(1), 1);
>  }
>
>  static bool ade_crtc_mode_fixup(struct drm_crtc *crtc,
> @@ -304,17 +302,6 @@ static void ade_crtc_disable_vblank(struct drm_crtc *crtc)
>                         MASK(1), 0);
>  }
>
> -static void drm_underflow_wq(struct work_struct *work)
> -{
> -       struct ade_hw_ctx *ctx = container_of(work, struct ade_hw_ctx,
> -                                             display_reset_wq);
> -       struct drm_device *drm_dev = ctx->crtc->dev;
> -       struct drm_atomic_state *state;
> -
> -       state = drm_atomic_helper_suspend(drm_dev);
> -       drm_atomic_helper_resume(drm_dev, state);
> -}
> -
>  static irqreturn_t ade_irq_handler(int irq, void *data)
>  {
>         struct ade_hw_ctx *ctx = data;
> @@ -331,12 +318,6 @@ static irqreturn_t ade_irq_handler(int irq, void *data)
>                                 MASK(1), 1);
>                 drm_crtc_handle_vblank(crtc);
>         }
> -       if (status & BIT(UNDERFLOW_INT_EN_OFST)) {
> -               ade_update_bits(base + LDI_INT_CLR, UNDERFLOW_INT_EN_OFST,
> -                               MASK(1), 1);
> -               DRM_ERROR("LDI underflow!");
> -               schedule_work(&ctx->display_reset_wq);
> -       }
>
>         return IRQ_HANDLED;
>  }
> @@ -919,7 +900,6 @@ static void *ade_hw_ctx_alloc(struct platform_device *pdev,
>         if (ret)
>                 return ERR_PTR(-EIO);
>
> -       INIT_WORK(&ctx->display_reset_wq, drm_underflow_wq);
>         ctx->crtc = crtc;
>
>         return ctx;
> --
> 2.17.1
>

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH] drm: kirin: Revert "Fix for hikey620 display offset problem"
  2020-03-04  9:28 ` Xinliang Liu
@ 2020-03-04  9:32   ` Xinliang Liu
  0 siblings, 0 replies; 4+ messages in thread
From: Xinliang Liu @ 2020-03-04  9:32 UTC (permalink / raw)
  To: John Stultz
  Cc: lkml, Rongrong Zou, Xinwei Kong, Chen Feng, Sam Ravnborg,
	David Airlie, Daniel Vetter, dri-devel

On Wed, 4 Mar 2020 at 17:28, Xinliang Liu <xinliang.liu@linaro.org> wrote:
>
> On Wed, 4 Mar 2020 at 00:32, John Stultz <john.stultz@linaro.org> wrote:
> >
> > This reverts commit ff57c6513820efe945b61863cf4a51b79f18b592.
> >
> > With the commit ff57c6513820 ("drm: kirin: Fix for hikey620
> > display offset problem") we added support for handling LDI
> > overflows by resetting the hardware.
> >
> > However, its been observed that when we do hit the LDI overflow
> > condition, the irq seems to be screaming, and we do nothing but
> > stream:
> >   [drm:ade_irq_handler [kirin_drm]] *ERROR* LDI underflow!
> > over and over to the screen
> >
> > I've tried a few appraoches to avoid this, but none has yet
> > been successful and the cure here is worse then the original
> > disease, so revert this for now.
>
> Sorry to hear that. Then it seems such underflow errors can't be
> recovered via reset.
> Anyway, for this patch
> Acked-by: Xinliang Liu <z.liuxinliang@hisilicon.com>

Sorry , should be:
 Acked-by: Xinliang Liu <xinliang.liu@linaro.org>

>
> And applied to drm-misc .
>
> -xinliang
>
> >
> > Cc: Xinliang Liu <xinliang.liu@linaro.org>
> > Cc: Rongrong Zou <zourongrong@gmail.com>
> > Cc: Xinwei Kong <kong.kongxinwei@hisilicon.com>
> > Cc: Chen Feng <puck.chen@hisilicon.com>
> > Cc: Sam Ravnborg <sam@ravnborg.org>
> > Cc: David Airlie <airlied@linux.ie>
> > Cc: Daniel Vetter <daniel@ffwll.ch>
> > Cc: dri-devel <dri-devel@lists.freedesktop.org>
> > Fixes: ff57c6513820 ("drm: kirin: Fix for hikey620 display offset problem")
> > Signed-off-by: John Stultz <john.stultz@linaro.org>
> > ---
> >  .../gpu/drm/hisilicon/kirin/kirin_ade_reg.h   |  1 -
> >  .../gpu/drm/hisilicon/kirin/kirin_drm_ade.c   | 20 -------------------
> >  2 files changed, 21 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/hisilicon/kirin/kirin_ade_reg.h b/drivers/gpu/drm/hisilicon/kirin/kirin_ade_reg.h
> > index 0da860200410..e2ac09894a6d 100644
> > --- a/drivers/gpu/drm/hisilicon/kirin/kirin_ade_reg.h
> > +++ b/drivers/gpu/drm/hisilicon/kirin/kirin_ade_reg.h
> > @@ -83,7 +83,6 @@
> >  #define VSIZE_OFST                     20
> >  #define LDI_INT_EN                     0x741C
> >  #define FRAME_END_INT_EN_OFST          1
> > -#define UNDERFLOW_INT_EN_OFST          2
> >  #define LDI_CTRL                       0x7420
> >  #define BPP_OFST                       3
> >  #define DATA_GATE_EN                   BIT(2)
> > diff --git a/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c b/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c
> > index 73cd28a6ea07..86000127d4ee 100644
> > --- a/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c
> > +++ b/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c
> > @@ -46,7 +46,6 @@ struct ade_hw_ctx {
> >         struct clk *media_noc_clk;
> >         struct clk *ade_pix_clk;
> >         struct reset_control *reset;
> > -       struct work_struct display_reset_wq;
> >         bool power_on;
> >         int irq;
> >
> > @@ -136,7 +135,6 @@ static void ade_init(struct ade_hw_ctx *ctx)
> >          */
> >         ade_update_bits(base + ADE_CTRL, FRM_END_START_OFST,
> >                         FRM_END_START_MASK, REG_EFFECTIVE_IN_ADEEN_FRMEND);
> > -       ade_update_bits(base + LDI_INT_EN, UNDERFLOW_INT_EN_OFST, MASK(1), 1);
> >  }
> >
> >  static bool ade_crtc_mode_fixup(struct drm_crtc *crtc,
> > @@ -304,17 +302,6 @@ static void ade_crtc_disable_vblank(struct drm_crtc *crtc)
> >                         MASK(1), 0);
> >  }
> >
> > -static void drm_underflow_wq(struct work_struct *work)
> > -{
> > -       struct ade_hw_ctx *ctx = container_of(work, struct ade_hw_ctx,
> > -                                             display_reset_wq);
> > -       struct drm_device *drm_dev = ctx->crtc->dev;
> > -       struct drm_atomic_state *state;
> > -
> > -       state = drm_atomic_helper_suspend(drm_dev);
> > -       drm_atomic_helper_resume(drm_dev, state);
> > -}
> > -
> >  static irqreturn_t ade_irq_handler(int irq, void *data)
> >  {
> >         struct ade_hw_ctx *ctx = data;
> > @@ -331,12 +318,6 @@ static irqreturn_t ade_irq_handler(int irq, void *data)
> >                                 MASK(1), 1);
> >                 drm_crtc_handle_vblank(crtc);
> >         }
> > -       if (status & BIT(UNDERFLOW_INT_EN_OFST)) {
> > -               ade_update_bits(base + LDI_INT_CLR, UNDERFLOW_INT_EN_OFST,
> > -                               MASK(1), 1);
> > -               DRM_ERROR("LDI underflow!");
> > -               schedule_work(&ctx->display_reset_wq);
> > -       }
> >
> >         return IRQ_HANDLED;
> >  }
> > @@ -919,7 +900,6 @@ static void *ade_hw_ctx_alloc(struct platform_device *pdev,
> >         if (ret)
> >                 return ERR_PTR(-EIO);
> >
> > -       INIT_WORK(&ctx->display_reset_wq, drm_underflow_wq);
> >         ctx->crtc = crtc;
> >
> >         return ctx;
> > --
> > 2.17.1
> >

^ permalink raw reply	[flat|nested] 4+ messages in thread

* [PATCH] drm: kirin: Revert "Fix for hikey620 display offset problem"
@ 2020-02-19  4:37 John Stultz
  0 siblings, 0 replies; 4+ messages in thread
From: John Stultz @ 2020-02-19  4:37 UTC (permalink / raw)
  To: lkml
  Cc: John Stultz, Xinliang Liu, Rongrong Zou, Xinwei Kong, Chen Feng,
	Sam Ravnborg, David Airlie, Daniel Vetter, dri-devel

This reverts commit ff57c6513820efe945b61863cf4a51b79f18b592.

With the commit ff57c6513820 ("drm: kirin: Fix for hikey620
display offset problem") we added support for handling LDI
overflows by resetting the hardware.

However, its been observed that when we do hit the LDI overflow
condition, the irq seems to be screaming, and we do nothing but
stream:
  [drm:ade_irq_handler [kirin_drm]] *ERROR* LDI underflow!
over and over to the screen

I've tried a few appraoches to avoid this, but none has yet
been successful and the cure here is worse then the original
disease, so revert this for now.

Cc: Xinliang Liu <z.liuxinliang@hisilicon.com>
Cc: Rongrong Zou <zourongrong@gmail.com>
Cc: Xinwei Kong <kong.kongxinwei@hisilicon.com>
Cc: Chen Feng <puck.chen@hisilicon.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel <dri-devel@lists.freedesktop.org>
Fixes: ff57c6513820 ("drm: kirin: Fix for hikey620 display offset problem")
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
 .../gpu/drm/hisilicon/kirin/kirin_ade_reg.h   |  1 -
 .../gpu/drm/hisilicon/kirin/kirin_drm_ade.c   | 20 -------------------
 2 files changed, 21 deletions(-)

diff --git a/drivers/gpu/drm/hisilicon/kirin/kirin_ade_reg.h b/drivers/gpu/drm/hisilicon/kirin/kirin_ade_reg.h
index 0da860200410..e2ac09894a6d 100644
--- a/drivers/gpu/drm/hisilicon/kirin/kirin_ade_reg.h
+++ b/drivers/gpu/drm/hisilicon/kirin/kirin_ade_reg.h
@@ -83,7 +83,6 @@
 #define VSIZE_OFST			20
 #define LDI_INT_EN			0x741C
 #define FRAME_END_INT_EN_OFST		1
-#define UNDERFLOW_INT_EN_OFST		2
 #define LDI_CTRL			0x7420
 #define BPP_OFST			3
 #define DATA_GATE_EN			BIT(2)
diff --git a/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c b/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c
index 73cd28a6ea07..86000127d4ee 100644
--- a/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c
+++ b/drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c
@@ -46,7 +46,6 @@ struct ade_hw_ctx {
 	struct clk *media_noc_clk;
 	struct clk *ade_pix_clk;
 	struct reset_control *reset;
-	struct work_struct display_reset_wq;
 	bool power_on;
 	int irq;
 
@@ -136,7 +135,6 @@ static void ade_init(struct ade_hw_ctx *ctx)
 	 */
 	ade_update_bits(base + ADE_CTRL, FRM_END_START_OFST,
 			FRM_END_START_MASK, REG_EFFECTIVE_IN_ADEEN_FRMEND);
-	ade_update_bits(base + LDI_INT_EN, UNDERFLOW_INT_EN_OFST, MASK(1), 1);
 }
 
 static bool ade_crtc_mode_fixup(struct drm_crtc *crtc,
@@ -304,17 +302,6 @@ static void ade_crtc_disable_vblank(struct drm_crtc *crtc)
 			MASK(1), 0);
 }
 
-static void drm_underflow_wq(struct work_struct *work)
-{
-	struct ade_hw_ctx *ctx = container_of(work, struct ade_hw_ctx,
-					      display_reset_wq);
-	struct drm_device *drm_dev = ctx->crtc->dev;
-	struct drm_atomic_state *state;
-
-	state = drm_atomic_helper_suspend(drm_dev);
-	drm_atomic_helper_resume(drm_dev, state);
-}
-
 static irqreturn_t ade_irq_handler(int irq, void *data)
 {
 	struct ade_hw_ctx *ctx = data;
@@ -331,12 +318,6 @@ static irqreturn_t ade_irq_handler(int irq, void *data)
 				MASK(1), 1);
 		drm_crtc_handle_vblank(crtc);
 	}
-	if (status & BIT(UNDERFLOW_INT_EN_OFST)) {
-		ade_update_bits(base + LDI_INT_CLR, UNDERFLOW_INT_EN_OFST,
-				MASK(1), 1);
-		DRM_ERROR("LDI underflow!");
-		schedule_work(&ctx->display_reset_wq);
-	}
 
 	return IRQ_HANDLED;
 }
@@ -919,7 +900,6 @@ static void *ade_hw_ctx_alloc(struct platform_device *pdev,
 	if (ret)
 		return ERR_PTR(-EIO);
 
-	INIT_WORK(&ctx->display_reset_wq, drm_underflow_wq);
 	ctx->crtc = crtc;
 
 	return ctx;
-- 
2.17.1


^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2020-03-04  9:32 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
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2020-03-04  9:28 ` Xinliang Liu
2020-03-04  9:32   ` Xinliang Liu
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2020-02-19  4:37 John Stultz

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