soc/mediatek: dsi: adjust hfp_byte and hbp_byte if too small

If panel has too small hfp or hbp, hfp_byte or hbp_byte may become
very small value or negative value. When very small value or
negative value is used, the panel will be scrolling or distorted.
This patch adjusts their values so that they are greater than
the minimum value and keep total of them unchanged.

DSI transfer HBP or HFP, There are some extra packet. ex. packet
header(4byte) and eof(2byte) and (next)hs packet header(4 byte).
the hfp_byte = HFP * BPP - packet header(4byte) and eof(2byte)
and (next)hs packet header(4 byte). So the min hfp_byte is 2 when
HFP = 4.

This is equivalent to the Linux kernel DSI change in:
https://chromium-review.googlesource.com/c/chromiumos/third_party/
kernel/+/2186872

BUG=b:144824303
BRANCH=kukui
TEST=boot damu board with panel CMN N120ACA-EA1 (12" panel and its
     hbp only 6), the panel can display without scrolling or
     distortions.

Signed-off-by: Paul Ma <magf@bitland.corp-partner.google.com>
Change-Id: I608c01d41ae93c8d5094647bbf3e0ae4a23d814c
Reviewed-on: https://review.coreboot.org/c/coreboot/+/41163
Reviewed-by: Hung-Te Lin <hungte@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

0 files changed, 0 insertions, 0 deletions