[PATCH v4 1/5] drm/mxsfb: Move axi clk enable/disable to crtc enable/disable

From: Leonard Crestez <leonard.crestez@nxp.com>
To: Stefan Agner <stefan@agner.ch>, Marek Vasut <marex@denx.de>,
	Shawn Guo <shawnguo@kernel.org>
Cc: Philipp Zabel <p.zabel@pengutronix.de>,
	Robert Chiras <robert.chiras@nxp.com>,
	Fabio Estevam <fabio.estevam@nxp.com>,
	Anson Huang <Anson.Huang@nxp.com>,
	dri-devel@lists.freedesktop.org,
	Dong Aisheng <aisheng.dong@nxp.com>,
	linux-imx@nxp.com, kernel@pengutronix.de,
	linux-kernel@vger.kernel.org
Subject: [PATCH v4 1/5] drm/mxsfb: Move axi clk enable/disable to crtc enable/disable
Date: Wed,  8 Aug 2018 19:08:58 +0300	[thread overview]
Message-ID: <f0d719af219a7f922bcc0746e9f840c471c56c5d.1533743954.git.leonard.crestez@nxp.com> (raw)
In-Reply-To: <cover.1533743954.git.leonard.crestez@nxp.com>

The main axi clk is disabled at the end of mxsfb_crtc_mode_set_nofb and
immediately reenabled in mxsfb_enable_controller.

Avoid this by moving the handling of axi clk one level up to
mxsfb_crtc_enable. Do the same for mxsfb_crtc_disable for simmetry

This shouldn't have any functional effect.

Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
---
 drivers/gpu/drm/mxsfb/mxsfb_crtc.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/mxsfb/mxsfb_crtc.c b/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
index 0abe77675b76..e4fcbb65b969 100644
--- a/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
+++ b/drivers/gpu/drm/mxsfb/mxsfb_crtc.c
@@ -127,11 +127,10 @@ static void mxsfb_enable_controller(struct mxsfb_drm_private *mxsfb)
 	u32 reg;
 
 	if (mxsfb->clk_disp_axi)
 		clk_prepare_enable(mxsfb->clk_disp_axi);
 	clk_prepare_enable(mxsfb->clk);
-	mxsfb_enable_axi_clk(mxsfb);
 
 	/* If it was disabled, re-enable the mode again */
 	writel(CTRL_DOTCLK_MODE, mxsfb->base + LCDC_CTRL + REG_SET);
 
 	/* Enable the SYNC signals first, then the DMA engine */
@@ -157,12 +156,10 @@ static void mxsfb_disable_controller(struct mxsfb_drm_private *mxsfb)
 
 	reg = readl(mxsfb->base + LCDC_VDCTRL4);
 	reg &= ~VDCTRL4_SYNC_SIGNALS_ON;
 	writel(reg, mxsfb->base + LCDC_VDCTRL4);
 
-	mxsfb_disable_axi_clk(mxsfb);
-
 	clk_disable_unprepare(mxsfb->clk);
 	if (mxsfb->clk_disp_axi)
 		clk_disable_unprepare(mxsfb->clk_disp_axi);
 }
 
@@ -206,11 +203,10 @@ static void mxsfb_crtc_mode_set_nofb(struct mxsfb_drm_private *mxsfb)
 	/*
 	 * It seems, you can't re-program the controller if it is still
 	 * running. This may lead to shifted pictures (FIFO issue?), so
 	 * first stop the controller and drain its FIFOs.
 	 */
-	mxsfb_enable_axi_clk(mxsfb);
 
 	/* Mandatory eLCDIF reset as per the Reference Manual */
 	err = mxsfb_reset_block(mxsfb->base);
 	if (err)
 		return;
@@ -267,23 +263,23 @@ static void mxsfb_crtc_mode_set_nofb(struct mxsfb_drm_private *mxsfb)
 	       SET_VERT_WAIT_CNT(m->crtc_vtotal - m->crtc_vsync_start),
 	       mxsfb->base + LCDC_VDCTRL3);
 
 	writel(SET_DOTCLK_H_VALID_DATA_CNT(m->hdisplay),
 	       mxsfb->base + LCDC_VDCTRL4);
-
-	mxsfb_disable_axi_clk(mxsfb);
 }
 
 void mxsfb_crtc_enable(struct mxsfb_drm_private *mxsfb)
 {
+	mxsfb_enable_axi_clk(mxsfb);
 	mxsfb_crtc_mode_set_nofb(mxsfb);
 	mxsfb_enable_controller(mxsfb);
 }
 
 void mxsfb_crtc_disable(struct mxsfb_drm_private *mxsfb)
 {
 	mxsfb_disable_controller(mxsfb);
+	mxsfb_disable_axi_clk(mxsfb);
 }
 
 void mxsfb_plane_atomic_update(struct mxsfb_drm_private *mxsfb,
 			       struct drm_plane_state *state)
 {
-- 
2.17.1

