Re: [PATCH 20/21] drm: mxsfb: Merge mxsfb_set_pixel_fmt() and mxsfb_set_bus_fmt()

On 2020-03-09 20:52, Laurent Pinchart wrote:

The mxsfb_set_pixel_fmt() and mxsfb_set_bus_fmt() functions both deal with format configuration, are always called in a row from mxsfb_crtc_mode_set_nofb(), and set fields from the LCDC_CTRL register. This requires a read-modify-update cycle in mxsfb_set_bus_fmt(). Make this more efficient by merging them together.

Signed-off-by: Laurent Pinchart laurent.pinchart@ideasonboard.com

Reviewed-by: Stefan Agner stefan@agner.ch

---

drivers/gpu/drm/mxsfb/mxsfb_kms.c | 47 +++++++++++++------------------ 1 file changed, 19 insertions(+), 28 deletions(-)

diff --git a/drivers/gpu/drm/mxsfb/mxsfb_kms.c b/drivers/gpu/drm/mxsfb/mxsfb_kms.c index 19b937b383cf..f81f8c222c13 100644 --- a/drivers/gpu/drm/mxsfb/mxsfb_kms.c +++ b/drivers/gpu/drm/mxsfb/mxsfb_kms.c @@ -42,13 +42,23 @@ static u32 set_hsync_pulse_width(struct mxsfb_drm_private *mxsfb, u32 val) mxsfb->devdata->hs_wdth_shift; }

-/* Setup the MXSFB registers for decoding the pixels out of the framebuffer */ -static void mxsfb_set_pixel_fmt(struct mxsfb_drm_private *mxsfb) +/*

• • Setup the MXSFB registers for decoding the pixels out of the framebuffer and
• • outputting them on the bus.
• */

+static void mxsfb_set_formats(struct mxsfb_drm_private *mxsfb) { struct drm_device *drm = mxsfb->drm; const u32 format = mxsfb->crtc.primary->state->fb->format->format;

• u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24; u32 ctrl, ctrl1;

• if (mxsfb->connector->display_info.num_bus_formats)

• bus_format = mxsfb->connector->display_info.bus_formats[0];
  

• DRM_DEV_DEBUG_DRIVER(drm->dev, "Using bus_format: 0x%08X\n",

• 	     bus_format);
  

• ctrl = CTRL_BYPASS_COUNT | CTRL_MASTER;

  /* CTRL1 contains IRQ config and status bits, preserve those. */

@@ -69,40 +79,23 @@ static void mxsfb_set_pixel_fmt(struct mxsfb_drm_private *mxsfb) break; }

• writel(ctrl1, mxsfb->base + LCDC_CTRL1);
• writel(ctrl, mxsfb->base + LCDC_CTRL);

-}

-static void mxsfb_set_bus_fmt(struct mxsfb_drm_private *mxsfb) -{

• struct drm_device *drm = mxsfb->drm;
• u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
• u32 reg;
• reg = readl(mxsfb->base + LCDC_CTRL);
• if (mxsfb->connector->display_info.num_bus_formats)

• bus_format = mxsfb->connector->display_info.bus_formats[0];
  

• DRM_DEV_DEBUG_DRIVER(drm->dev, "Using bus_format: 0x%08X\n",

• 	     bus_format);
  

• reg &= ~CTRL_BUS_WIDTH_MASK; switch (bus_format) { case MEDIA_BUS_FMT_RGB565_1X16:

• reg |= CTRL_BUS_WIDTH_16;
  

• ctrl |= CTRL_BUS_WIDTH_16;
  

  break; case MEDIA_BUS_FMT_RGB666_1X18:

• reg |= CTRL_BUS_WIDTH_18;
  

• ctrl |= CTRL_BUS_WIDTH_18;
  

  break; case MEDIA_BUS_FMT_RGB888_1X24:

• reg |= CTRL_BUS_WIDTH_24;
  

• ctrl |= CTRL_BUS_WIDTH_24;
  

  break; default: dev_err(drm->dev, "Unknown media bus format %d\n", bus_format); break; }

• writel(reg, mxsfb->base + LCDC_CTRL);

• writel(ctrl1, mxsfb->base + LCDC_CTRL1);
• writel(ctrl, mxsfb->base + LCDC_CTRL);

}

static void mxsfb_enable_controller(struct mxsfb_drm_private *mxsfb) @@ -213,7 +206,7 @@ static void mxsfb_crtc_mode_set_nofb(struct mxsfb_drm_private *mxsfb) /* Clear the FIFOs */ writel(CTRL1_FIFO_CLEAR, mxsfb->base + LCDC_CTRL1 + REG_SET);

• mxsfb_set_pixel_fmt(mxsfb);

• mxsfb_set_formats(mxsfb);

  clk_set_rate(mxsfb->clk, m->crtc_clock * 1000);

@@ -255,8 +248,6 @@ static void mxsfb_crtc_mode_set_nofb(struct mxsfb_drm_private *mxsfb)

writel(vdctrl0, mxsfb->base + LCDC_VDCTRL0);

• mxsfb_set_bus_fmt(mxsfb);
• /* Frame length in lines. */ writel(m->crtc_vtotal, mxsfb->base + LCDC_VDCTRL1);