Re: [PATCH v2/2] i915: Support Intel GPU porting on any non-x86 system.

[ZhangZhiJie]

Hi. Jani

On 2025/11/25 16:38, Jani Nikula wrote:
> On Tue, 25 Nov 2025, zhangzhijie <zhangzhijie@xxxxxxxxxx> wrote:
> > inb/outb speccial wire not support on other ARCH.
> > Should detect whether arch platform support or not.
>
> I would rather finish the discussion on the previous version before
> seeing a new version.
>
> You mentioned risc-v in the previous thread, but it needs to be part of
> the commit message too. And I still don't know what "speccial wire" is
> supposed to mean here.
I using RISCV to bootingup A380, This arch not support  VGA_SEQ_* 
ioports. and i don't know if other arch(such as aarch64) has VGA_SEQ_*.
> You still use likely/unlikely, and I told you not to.
Ok, Next patch will fixed.
> There's no patch changelog.
>
> The version in the subject is "v2/2", but there has already been two
> "v2" posted previously.
After sending emails using V2, I realized that I had used V2 before, so 
I started using V2/2. Can I use V3 to continue with subsequent 
patch-modified commits?
> BR,
> Jani.
>
>
> > Signed-off-by: zhangzhijie <zhangzhijie@xxxxxxxxxx>
> > ---
> >   drivers/gpu/drm/i915/display/intel_vga.c | 33 +++++++++++++++++-------
> >   1 file changed, 23 insertions(+), 10 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_vga.c b/drivers/gpu/drm/i915/display/intel_vga.c
> > index 6e125564db34..d85622ba10fc 100644
> > --- a/drivers/gpu/drm/i915/display/intel_vga.c
> > +++ b/drivers/gpu/drm/i915/display/intel_vga.c
> > @@ -41,6 +41,15 @@ static bool has_vga_pipe_sel(struct intel_display *display)
> >   	return DISPLAY_VER(display) < 7;
> >   }
> >   
> > +static bool intel_arch_support_vga_pm(struct intel_display *display)
> > +{
> > +#if defined(CONFIG_X86) || defined(CONFIG_X86_64)
> > +	return true;
> > +#else
> > +	return false;
> > +#endif
> > +}
> > +
> >   /* Disable the VGA plane that we never use */
> >   void intel_vga_disable(struct intel_display *display)
> >   {
> > @@ -64,13 +73,15 @@ void intel_vga_disable(struct intel_display *display)
> >   	drm_dbg_kms(display->drm, "Disabling VGA plane on pipe %c\n",
> >   		    pipe_name(pipe));
> >   
> > -	/* WaEnableVGAAccessThroughIOPort:ctg,elk,ilk,snb,ivb,vlv,hsw */
> > -	vga_get_uninterruptible(pdev, VGA_RSRC_LEGACY_IO);
> > -	outb(0x01, VGA_SEQ_I);
> > -	sr1 = inb(VGA_SEQ_D);
> > -	outb(sr1 | VGA_SR01_SCREEN_OFF, VGA_SEQ_D);
> > -	vga_put(pdev, VGA_RSRC_LEGACY_IO);
> > -	udelay(300);
> > +	if (likely(intel_arch_support_vga_pm(display))) {
> > +		/* WaEnableVGAAccessThroughIOPort:ctg,elk,ilk,snb,ivb,vlv,hsw */
> > +		vga_get_uninterruptible(pdev, VGA_RSRC_LEGACY_IO);
> > +		outb(0x01, VGA_SEQ_I);
> > +		sr1 = inb(VGA_SEQ_D);
> > +		outb(sr1 | VGA_SR01_SCREEN_OFF, VGA_SEQ_D);
> > +		vga_put(pdev, VGA_RSRC_LEGACY_IO);
> > +		udelay(300);
> > +	}
> >   
> >   	intel_de_write(display, vga_reg, VGA_DISP_DISABLE);
> >   	intel_de_posting_read(display, vga_reg);
> > @@ -90,9 +101,11 @@ void intel_vga_reset_io_mem(struct intel_display *display)
> >   	 * sure vgacon can keep working normally without triggering interrupts
> >   	 * and error messages.
> >   	 */
> > -	vga_get_uninterruptible(pdev, VGA_RSRC_LEGACY_IO);
> > -	outb(inb(VGA_MIS_R), VGA_MIS_W);
> > -	vga_put(pdev, VGA_RSRC_LEGACY_IO);
> > +	if (likely(intel_arch_support_vga_pm(display))) {
> > +		vga_get_uninterruptible(pdev, VGA_RSRC_LEGACY_IO);
> > +		outb(inb(VGA_MIS_R), VGA_MIS_W);
> > +		vga_put(pdev, VGA_RSRC_LEGACY_IO);
> > +	}
> >   }
> >   
> >   int intel_vga_register(struct intel_display *display)