Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Xinliang Liu <xinliang.liu@linaro.org>,
        Rongrong Zou <zourongrong@gmail.com>,
        Xinwei Kong <kong.kongxinwei@hisilicon.com>,
        Chen Feng <puck.chen@hisilicon.com>,
        Sam Ravnborg <sam@ravnborg.org>,
        David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>,
        dri-devel <dri-devel@lists.freedesktop.org>,
        John Stultz <john.stultz@linaro.org>
Subject: [PATCH 5.5 144/189] drm: kirin: Revert "Fix for hikey620 display offset problem"
Date:   Tue, 10 Mar 2020 13:39:41 +0100
Message-Id: <20200310123654.404244877@linuxfoundation.org>
In-Reply-To: <20200310123639.608886314@linuxfoundation.org>
References: <20200310123639.608886314@linuxfoundation.org>
User-Agent: quilt/0.66
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

From: John Stultz <john.stultz@linaro.org>

commit 1b79cfd99ff5127e6a143767b51694a527b3ea38 upstream.

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>
Acked-by: Xinliang Liu <xinliang.liu@linaro.org>
Signed-off-by: Xinliang Liu <xinliang.liu@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200303163228.52741-1-john.stultz@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/gpu/drm/hisilicon/kirin/kirin_ade_reg.h |    1 -
 drivers/gpu/drm/hisilicon/kirin/kirin_drm_ade.c |   20 --------------------
 2 files changed, 21 deletions(-)

--- 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)
--- 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 *
 	 */
 	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(stru
 			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 i
 				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 pla
 	if (ret)
 		return ERR_PTR(-EIO);
 
-	INIT_WORK(&ctx->display_reset_wq, drm_underflow_wq);
 	ctx->crtc = crtc;
 
 	return ctx;