Re: [Qemu-devel] [PATCH] [RESEND] SM501 emulation for R2D-SH4

["Blue Swirl" <blauwirbel@gmail.com>]

On 11/5/08, andrzej zaborowski <balrogg@gmail.com> wrote:
> 2008/11/5 Blue Swirl <blauwirbel@gmail.com>:
>
> > On 11/5/08, Shin-ichiro KAWASAKI <kawasaki@juno.dti.ne.jp> wrote:
>  >> Blue Swirl wrote:
>  >>
>  >> > On 11/4/08, Shin-ichiro KAWASAKI <kawasaki@juno.dti.ne.jp> wrote:
>  >> >
>  >> > > Thank you for reviewing!
>  >> > >
>  >> > >  I add the new version of patch to this mail, which reflects
>  >> > >  you and andrzej's comments.  Some more comments on it will be
>  >> > >  appreciated.  Especially advice on VRAM implementation with
>  >> > >  normal RAM will be useful for me.
>  >> > >
>  >> > > > The display buffer should be allocated using machine definition
>  >> > > >
>  >> > > .ram_require.
>  >> > >  I tried normal RAM implementation : "#define USE_NORMAL_RAM" in the
>  >> patch
>  >> > > will
>  >> > >  turn the new implementation on.  But it causes system hang during
>  >> SH-Linux
>  >> > > boot up.
>  >> > >  The initial VRAM clearance seems to cause the hang.
>  >> > >  The reason might be my wrong implementation, or any MMU problem of SH4.
>  >> > >
>  >> > >  I did,
>  >> > >  - added VRAM size to .ram_require
>  >> > >  - invoked qemu_ram_alloc() with the VRAM size parameter,
>  >> > >  - and invoked cpu_register_physical_memory(), passing
>  >> the
>  >> > > return value of
>  >> > >  qemu_ram_alloc() as third parameter.
>  >> > >
>  >> > >  Is this sequence correct?
>  >> > >
>  >> >
>  >> > Yes, but the system RAM is not allocated using qemu_ram_alloc. Now
>  >> > qemu_ram_alloc gives the same area (0 to VRAM_SIZE) the second time.
>  >> >
>  >> > So the following:
>  >> >    /* Allocate memory space */
>  >> >    cpu_register_physical_memory(SDRAM_BASE, SDRAM_SIZE,
>  >> 0);
>  >> > should be changed to:
>  >> >    ram_addr = qemu_ram_alloc(SDRAM_SIZE);
>  >> >    cpu_register_physical_memory(SDRAM_BASE, SDRAM_SIZE,
>  >> ram_addr);
>  >> >
>  >> > Maybe that helps?
>  >> >
>  >>
>  >>  Yes, it helps.  Thank you!
>  >>
>  >>  Here's the new patch which uses normal RAM as the VRAM, and
>  >>  checks VGA_DIRTY_FLAG for partial update.
>  >>
>  >>  I think it is ready for merge to the trunk.
>  >>  Could anyone help it?
>  >
>  > Looks good to me. What about you, Andrzej?
>
>
> While I don't know the hardware, it looks correct to me, feel free to merge.

Committed as r5632. Thanks!