[PATCH 62/72] imx-drm: ipuv3-plane: Assign correct dmfc burst size

[Steve Longerbeam]

According to the imx6 reference manual, the DMFC channel's
burstsize must match the corresponding IDMAC channel's burstsize,
so make sure to pass the IDMAC channel burstsize to
ipu_dmfc_alloc_bandwidth(). We need to move ipu_dmfc_alloc_bandwidth()
to after the channel is setup, in order to first initialize the
channel burstsize, before retrieving it with ipu_cpmem_get_burstsize().

Signed-off-by: Steve Longerbeam <steve_longerbeam at mentor.com>
---
 drivers/staging/imx-drm/ipuv3-plane.c |   20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/drivers/staging/imx-drm/ipuv3-plane.c 
b/drivers/staging/imx-drm/ipuv3-plane.c
index 61d47e9..aa10ae7 100644
--- a/drivers/staging/imx-drm/ipuv3-plane.c
+++ b/drivers/staging/imx-drm/ipuv3-plane.c
@@ -159,7 +159,7 @@ int ipu_plane_mode_set(struct ipu_plane *ipu_plane, struct 
drm_crtc *crtc,
 {
        struct device *dev = ipu_plane->base.dev->dev;
        bool is_bg = (ipu_plane->dp_flow == IPU_DP_FLOW_SYNC_BG);
-       int ret;
+       int burstsize, ret;

        /* no scaling */
        if (src_w != crtc_w || src_h != crtc_h)
@@ -238,14 +238,6 @@ int ipu_plane_mode_set(struct ipu_plane *ipu_plane, struct 
drm_crtc *crtc,
                }
        }

-       ret = ipu_dmfc_alloc_bandwidth(ipu_plane->dmfc,
-                       calc_bandwidth(crtc_w, crtc_h,
-                                      calc_vref(mode)), crtc_w, 64);
-       if (ret) {
-               dev_err(dev, "allocating dmfc bandwidth failed with %d\n", ret);
-               return ret;
-       }
-
        ipu_cpmem_zero(ipu_plane->ipu_ch);
        ipu_cpmem_set_resolution(ipu_plane->ipu_ch, src_w, src_h);
        ret = ipu_cpmem_set_fmt(ipu_plane->ipu_ch, fb->pixel_format);
@@ -260,6 +252,16 @@ int ipu_plane_mode_set(struct ipu_plane *ipu_plane, struct 
drm_crtc *crtc,

        ipu_cpmem_set_high_priority(ipu_plane->ipu_ch);

+       burstsize = ipu_cpmem_get_burstsize(ipu_plane->ipu_ch);
+
+       ret = ipu_dmfc_alloc_bandwidth(ipu_plane->dmfc,
+                       calc_bandwidth(crtc_w, crtc_h,
+                                      calc_vref(mode)), crtc_w, burstsize);
+       if (ret) {
+               dev_err(dev, "allocating dmfc bandwidth failed with %d\n", ret);
+               return ret;
+       }
+
        /* enable double-buffering */
        ipu_idmac_set_double_buffer(ipu_plane->ipu_ch, true);

-- 
1.7.9.5