| From ec1587d5073f29820e358f3a383850d61601d981 Mon Sep 17 00:00:00 2001 |
| From: Yifeng Li <tomli@tomli.me> |
| Date: Mon, 1 Apr 2019 17:46:59 +0200 |
| Subject: fbdev: sm712fb: fix boot screen glitch when sm712fb replaces VGA |
| |
| From: Yifeng Li <tomli@tomli.me> |
| |
| commit ec1587d5073f29820e358f3a383850d61601d981 upstream. |
| |
| When the machine is booted in VGA mode, loading sm712fb would cause |
| a glitch of random pixels shown on the screen. To prevent it from |
| happening, we first clear the entire framebuffer, and we also need |
| to stop calling smtcfb_setmode() during initialization, the fbdev |
| layer will call it for us later when it's ready. |
| |
| Signed-off-by: Yifeng Li <tomli@tomli.me> |
| Tested-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> |
| Cc: Teddy Wang <teddy.wang@siliconmotion.com> |
| Cc: <stable@vger.kernel.org> # v4.4+ |
| Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/video/fbdev/sm712fb.c | 6 +++++- |
| 1 file changed, 5 insertions(+), 1 deletion(-) |
| |
| --- a/drivers/video/fbdev/sm712fb.c |
| +++ b/drivers/video/fbdev/sm712fb.c |
| @@ -1492,7 +1492,11 @@ static int smtcfb_pci_probe(struct pci_d |
| if (err) |
| goto failed; |
| |
| - smtcfb_setmode(sfb); |
| + /* |
| + * The screen would be temporarily garbled when sm712fb takes over |
| + * vesafb or VGA text mode. Zero the framebuffer. |
| + */ |
| + memset_io(sfb->lfb, 0, sfb->fb->fix.smem_len); |
| |
| err = register_framebuffer(info); |
| if (err < 0) |
