On Mon, 24 Nov 2025, zhangzhijie <[email protected]> wrote: > inb/outb speccial wire not support on other ARCH. > Should detect whether arch platform support or not.
Seems to me it inb/outb depend on CONFIG_HAS_IOPORT. Which arch are you talking about specifically? > Signed-off-by: zhangzhijie <[email protected]> > --- > drivers/gpu/drm/i915/display/intel_vga.c | 27 ++++++++++++++++++------ > 1 file changed, 20 insertions(+), 7 deletions(-) > > diff --git a/drivers/gpu/drm/i915/display/intel_vga.c > b/drivers/gpu/drm/i915/display/intel_vga.c > index 6e125564db34..d5d6c4ba6434 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) > { > @@ -66,11 +75,13 @@ void intel_vga_disable(struct intel_display *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); > + if (likely(intel_arch_support_vga_pm(display))) { As a rule of thumb, please do not use likely/unlikely, at all. Here, intel_arch_support_vga_pm() is evaluated at build time, and the likely has no functional value, only dubious documentation value. > + 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); Both or neither get/put need to be inside the branch. Now you only get, never put, on non-x86. BR, Jani. > + udelay(300); > + } > > intel_de_write(display, vga_reg, VGA_DISP_DISABLE); > intel_de_posting_read(display, vga_reg); > @@ -91,8 +102,10 @@ void intel_vga_reset_io_mem(struct intel_display *display) > * 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))) { > + outb(inb(VGA_MIS_R), VGA_MIS_W); > + vga_put(pdev, VGA_RSRC_LEGACY_IO); > + } > } > > int intel_vga_register(struct intel_display *display) -- Jani Nikula, Intel
