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 <zhangzhi...@bosc.ac.cn> 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 <zhangzhi...@bosc.ac.cn>
---
  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)