From 0c80d60ae63461c33293859fc41ba57654dc863a Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ville=20Syrj=C3=A4l=C3=A4?= Date: Thu, 17 Apr 2025 14:44:52 +0300 Subject: [PATCH] drm/i915/vga: Include the current pipe in the VGA disable debug message MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Add some debugs to the VGA plane disable so that we can at least see from the logs when it happens (and on which pipe). I was curious about this at some point when I was seeing some random underruns near the time when we disable the VGA plane, but I think in the end that turned out to be a red herring. Signed-off-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20250417114454.12836-5-ville.syrjala@linux.intel.com Reviewed-by: Jani Nikula --- drivers/gpu/drm/i915/display/intel_vga.c | 29 +++++++++++++++++++++++- 1 file changed, 28 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/display/intel_vga.c b/drivers/gpu/drm/i915/display/intel_vga.c index 335e6c45deb2..508c69b91a76 100644 --- a/drivers/gpu/drm/i915/display/intel_vga.c +++ b/drivers/gpu/drm/i915/display/intel_vga.c @@ -15,6 +15,7 @@ #include "i915_reg.h" #include "intel_de.h" +#include "intel_display.h" #include "intel_vga.h" #include "intel_vga_regs.h" @@ -28,16 +29,42 @@ static i915_reg_t intel_vga_cntrl_reg(struct intel_display *display) return VGACNTRL; } +static bool has_vga_pipe_sel(struct intel_display *display) +{ + if (display->platform.i845g || + display->platform.i865g) + return false; + + if (display->platform.valleyview || + display->platform.cherryview) + return true; + + return DISPLAY_VER(display) < 7; +} + /* Disable the VGA plane that we never use */ void intel_vga_disable(struct intel_display *display) { struct pci_dev *pdev = to_pci_dev(display->drm->dev); i915_reg_t vga_reg = intel_vga_cntrl_reg(display); + enum pipe pipe; + u32 tmp; u8 sr1; - if (intel_de_read(display, vga_reg) & VGA_DISP_DISABLE) + tmp = intel_de_read(display, vga_reg); + if (tmp & VGA_DISP_DISABLE) return; + if (display->platform.cherryview) + pipe = REG_FIELD_GET(VGA_PIPE_SEL_MASK_CHV, tmp); + else if (has_vga_pipe_sel(display)) + pipe = REG_FIELD_GET(VGA_PIPE_SEL_MASK, tmp); + else + pipe = PIPE_A; + + 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); -- 2.25.1