Re: [PATCH i-g-t v5] lib/intel_chipset: Extend intel_get_pci_device to PCI accelerator class

["Dixit, Ashutosh" <ashutosh.dixit@intel.com>]

On Fri, 19 Jun 2026 04:24:11 -0700, Kamil Konieczny wrote:
>
> Hi Ashutosh,
> On 2026-06-18 at 16:54:03 -0700, Ashutosh Dixit wrote:
> > In addition to PCI display class devices, Intel devices can also be PCI
> > accelerator class devices. Extend intel_get_pci_device() to also find these
> > devices.
> >
> > v2: Introduce intel_get_pci_device_disp for those tools who specifically
> >     want only display class devices (Kamil)
> > v3: Same as v2
> > v4: s/intel_get_pci_device_disp/intel_get_pci_device_display/
> > v5: More code refactor (Kamil)
> >
> > Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
> > ---
> >  lib/intel_chipset.c             | 56 +++++++++++++++++++++++++++------
> >  lib/intel_chipset.h             |  1 +
> >  tools/intel_audio_dump.c        |  2 +-
> >  tools/intel_backlight.c         |  2 +-
> >  tools/intel_display_bandwidth.c |  4 +--
> >  tools/intel_display_poller.c    |  4 +--
> >  tools/intel_panel_fitter.c      |  2 +-
> >  7 files changed, 55 insertions(+), 16 deletions(-)
> >
> > diff --git a/lib/intel_chipset.c b/lib/intel_chipset.c
> > index 760faede24..c0a350588e 100644
> > --- a/lib/intel_chipset.c
> > +++ b/lib/intel_chipset.c
> > @@ -64,15 +64,14 @@
> >  enum pch_type intel_pch;
> >
> >  /**
> > - * intel_get_pci_device:
> > + * intel_pci_device_by_class:
> >   *
> >   * Looks up the main graphics pci device using libpciaccess.
> >   *
> >   * Returns:
> >   * The pci_device, exits the program on any failures.
> >   */
> > -struct pci_device *
> > -intel_get_pci_device(void)
> > +static struct pci_device *intel_pci_device_by_class(uint8_t class)
>
> Hmm, better to make s/uint8_t/unsigned int/
> sorry for confusion
>
> >  {
> >	struct pci_device *pci_dev;
> >	int error;
> > @@ -81,7 +80,7 @@ intel_get_pci_device(void)
> >	igt_fail_on_f(error != 0,
> >		      "Couldn't initialize PCI system\n");
> >
> > -	/* Grab the graphics card. Try the canonical slot first, then
> > +	/* Grab the Intel device. Try the canonical slot first, then
> >	 * walk the entire PCI bus for a matching device. */
> >	pci_dev = pci_device_find_by_slot(0, 0, 2, 0);
> >	if (pci_dev == NULL || pci_dev->vendor_id != 0x8086) {
> > @@ -93,7 +92,7 @@ intel_get_pci_device(void)
> >		match.subvendor_id = PCI_MATCH_ANY;
> >		match.subdevice_id = PCI_MATCH_ANY;
> >
> > -		match.device_class = 0x3 << 16;
> > +		match.device_class = class << 16;
>
> Technically, uint8_t << 16 is zero.

OK, I changed it in v6 but I did test it and it works, because of "type
promotion".

>
> >		match.device_class_mask = 0xff << 16;
> >
> >		match.match_data = 0;
> > @@ -102,14 +101,53 @@ intel_get_pci_device(void)
> >		pci_dev = pci_device_next(iter);
> >		pci_iterator_destroy(iter);
> >	}
> > -	igt_require_f(pci_dev, "Couldn't find Intel graphics card\n");
> > +	if (!pci_dev)
> > +		return NULL;
> >
> >	error = pci_device_probe(pci_dev);
> > -	igt_fail_on_f(error != 0,
> > -		      "Couldn't probe graphics card\n");
> > +	igt_fail_on_f(error != 0, "Couldn't probe the device\n");
>
> Add printing class here.

Done.

> With above fixed this is
> Reviewed-by: Kamil Konieczny <kamil.konieczny@linux.intel.com>

Thanks.
--
Ashutosh


> >
> >	if (pci_dev->vendor_id != 0x8086)
> > -		errx(1, "Graphics card is non-intel");
> > +		errx(1, "PCI device 0x%02x card is non-intel", class);
> > +
> > +	return pci_dev;
> > +}
> > +
> > +/**
> > + * intel_get_pci_device_display:
> > + *
> > + * Looks up display class pci device using libpciaccess
> > + *
> > + * Returns: The pci_device, exits the program on any failures
> > + */
> > +struct pci_device *intel_get_pci_device_display(void)
> > +{
> > +	/* PCI display class (0x3) device */
> > +	struct pci_device *pci_dev = intel_pci_device_by_class(0x3);
> > +
> > +	igt_require_f(pci_dev, "Couldn't find Intel graphics device\n");
> > +
> > +	return pci_dev;
> > +}
> > +
> > +
> > +/**
> > + * intel_get_pci_device:
> > + *
> > + * Looks up display and accelerator class pci devices using libpciaccess
> > + *
> > + * Returns: The pci_device, exits the program on any failures
> > + */
> > +struct pci_device *intel_get_pci_device(void)
> > +{
> > +	/* PCI display class (0x3) device */
> > +	struct pci_device *pci_dev = intel_pci_device_by_class(0x3);
> > +
> > +	/* PCI accelerator class (0x12) device */
> > +	if (!pci_dev)
> > +		pci_dev = intel_pci_device_by_class(0x12);
> > +
> > +	igt_require_f(pci_dev, "Couldn't find Intel graphics or accelerator device\n");
> >
> >	return pci_dev;
> >  }
> > diff --git a/lib/intel_chipset.h b/lib/intel_chipset.h
> > index 98a2a81fcf..1f02932e4a 100644
> > --- a/lib/intel_chipset.h
> > +++ b/lib/intel_chipset.h
> > @@ -36,6 +36,7 @@
> >  #define BIT(x) (1ul <<(x))
> >
> >  struct pci_device *intel_get_pci_device(void);
> > +struct pci_device *intel_get_pci_device_display(void);
> >  uint32_t intel_get_drm_devid(int fd);
> >
> >  struct intel_device_info {
> > diff --git a/tools/intel_audio_dump.c b/tools/intel_audio_dump.c
> > index 287dbd4759..5761fc1bbc 100644
> > --- a/tools/intel_audio_dump.c
> > +++ b/tools/intel_audio_dump.c
> > @@ -2468,7 +2468,7 @@ int main(int argc, char **argv)
> >	struct pci_device *pci_dev;
> >	struct intel_mmio_data mmio_data;
> >
> > -	pci_dev = intel_get_pci_device();
> > +	pci_dev = intel_get_pci_device_display();
> >	devid = pci_dev->device_id; /* XXX not true when mapping! */
> >
> >	do_self_tests();
> > diff --git a/tools/intel_backlight.c b/tools/intel_backlight.c
> > index edf060224f..1478583e97 100644
> > --- a/tools/intel_backlight.c
> > +++ b/tools/intel_backlight.c
> > @@ -41,7 +41,7 @@ int main(int argc, char** argv)
> >	struct intel_mmio_data mmio_data;
> >	uint32_t current, max;
> >
> > -	intel_mmio_use_pci_bar(&mmio_data, intel_get_pci_device());
> > +	intel_mmio_use_pci_bar(&mmio_data, intel_get_pci_device_display());
> >
> >	current = INREG(BLC_PWM_CPU_CTL) & BACKLIGHT_DUTY_CYCLE_MASK;
> >	max = INREG(BLC_PWM_PCH_CTL2) >> 16;
> > diff --git a/tools/intel_display_bandwidth.c b/tools/intel_display_bandwidth.c
> > index b798f8b652..193f309d39 100644
> > --- a/tools/intel_display_bandwidth.c
> > +++ b/tools/intel_display_bandwidth.c
> > @@ -152,14 +152,14 @@ int main(int argc, char *argv[])
> >		}
> >	}
> >
> > -	devid = intel_get_pci_device()->device_id;
> > +	devid = intel_get_pci_device_display()->device_id;
> >
> >	if (!has_de_power2(devid)) {
> >		fprintf(stderr, "Display bandwidth counter not available\n");
> >		return 2;
> >	}
> >
> > -	intel_register_access_init(&mmio_data, intel_get_pci_device(), 0);
> > +	intel_register_access_init(&mmio_data, intel_get_pci_device_display(), 0);
> >
> >	if (has_de_power2_abox0_abox1(devid))
> >		measure_de_power2_abox0_abox1(devid, sleep_duration);
> > diff --git a/tools/intel_display_poller.c b/tools/intel_display_poller.c
> > index 6338f22223..df333597e7 100644
> > --- a/tools/intel_display_poller.c
> > +++ b/tools/intel_display_poller.c
> > @@ -1508,7 +1508,7 @@ int main(int argc, char *argv[])
> >		}
> >	}
> >
> > -	devid = intel_get_pci_device()->device_id;
> > +	devid = intel_get_pci_device_display()->device_id;
> >
> >	/*
> >	 * check if the requires registers are
> > @@ -1677,7 +1677,7 @@ int main(int argc, char *argv[])
> >		break;
> >	}
> >
> > -	intel_register_access_init(&mmio_data, intel_get_pci_device(), 0);
> > +	intel_register_access_init(&mmio_data, intel_get_pci_device_display(), 0);
> >
> >	if (auto_scanline_offset)
> >		scanline_offset = default_scanline_offset(devid, pipe);
> > diff --git a/tools/intel_panel_fitter.c b/tools/intel_panel_fitter.c
> > index d9555d5c67..2234eac6c4 100644
> > --- a/tools/intel_panel_fitter.c
> > +++ b/tools/intel_panel_fitter.c
> > @@ -280,7 +280,7 @@ int main (int argc, char *argv[])
> >	       "with overscan compensation properties: it is just a temporary "
> >	       "solution that may or may not work. Use it at your own risk.\n");
> >
> > -	pci_dev = intel_get_pci_device();
> > +	pci_dev = intel_get_pci_device_display();
> >	intel_register_access_init(&mmio_data, pci_dev, 0);
> >	devid = pci_dev->device_id;
> >
> > --
> > 2.54.0
> >