On Thu, Apr 23, 2020 at 02:14:48PM +0200, Markus Elfring wrote:
> > the sfb->fb->screen_base is not save the value get by iounmap() when
> > the chip id is 0x720.
>
> I suggest to improve this change description.
> How did you determine relevant differences for the mentioned chip model?
>
Read and check its codes。
smtcfb_pci_probe() --> smtc_map_smem()
smtcfb_pci_probe()
switch (sfb->chip_id) {
case 0x710:
case 0x712:
sfb->lfb = ioremap(mmio_base, mmio_addr);
case 0x720:
sfb->dp_regs = ioremap(mmio_base, 0x00200000 + smem_size);
sfb->lfb = sfb->dp_regs + 0x00200000;
}
smtc_map_smem()
sfb->fb->screen_base = sfb->lfb;
smtcfb_pci_remove() --> smtc_unmap_smem()
smtc_unmap_smem()
iounmap(sfb->fb->screen_base);
>
> > so iounmap() for address sfb->fb->screen_base is not right.
>
> Will another imperative wording become helpful here?
>
yes, this is why need to change this code.
>
> …
> > +++ b/drivers/video/fbdev/sm712fb.c
> > @@ -1429,6 +1429,8 @@ static int smtc_map_smem(struct smtcfb_info *sfb,
> > static void smtc_unmap_smem(struct smtcfb_info *sfb)
> > {
> > if (sfb && sfb->fb->screen_base) {
> > + if (sfb->chip_id == 0x720)
> > + sfb->fb->screen_base -= 0x00200000;
> > iounmap(sfb->fb->screen_base);
>
> How do you think about to use descriptive identifiers for
> the shown constants?
>
These two constants are originally in the driver, I don't know enough
about its meaning, There are a lot of constants in this driver. If I
replace it with the macro, I worry that the name of the macro may not
be accurate.
> Would you like to clarify any related software analysis approaches?
>
just read coedes and check it.
> Regards,
> Markus
