Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
drm/imagination: Warn or error on unsupported hardware
Gate the use of unsupported hardware behind a new module parameter
(exp_hw_support).
Reviewed-by: Alessio Belle <alessio.belle@imgtec.com>
Link: https://patch.msgid.link/20260113-device-support-info-v1-6-91e5db7f7294@imgtec.com
Signed-off-by: Matt Coster <matt.coster@imgtec.com>
+72
-1
+72
-1
drivers/gpu/drm/imagination/pvr_device.c
+72
-1
drivers/gpu/drm/imagination/pvr_device.c
···
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}
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EXPORT_SYMBOL_IF_KUNIT(pvr_gpuid_decode_string);
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+
static bool pvr_exp_hw_support;
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module_param_named(exp_hw_support, pvr_exp_hw_support, bool, 0600);
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MODULE_PARM_DESC(exp_hw_support, "Bypass runtime checks for fully supported GPU cores. WARNING: enabling this option may result in a buggy, insecure, or otherwise unusable driver.");
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+
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/**
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* enum pvr_gpu_support_level - The level of support for a gpu_id in the current
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* version of the driver.
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*
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* @PVR_GPU_UNKNOWN: Cores that are unknown to the driver. These may not even exist.
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* @PVR_GPU_EXPERIMENTAL: Cores that have experimental support.
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* @PVR_GPU_SUPPORTED: Cores that are supported and maintained.
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*/
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enum pvr_gpu_support_level {
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PVR_GPU_UNKNOWN,
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PVR_GPU_EXPERIMENTAL,
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PVR_GPU_SUPPORTED,
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+
};
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+
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static enum pvr_gpu_support_level
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pvr_gpu_support_level(const struct pvr_gpu_id *gpu_id)
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+
{
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switch (pvr_gpu_id_to_packed_bvnc(gpu_id)) {
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case PVR_PACKED_BVNC(33, 15, 11, 3):
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case PVR_PACKED_BVNC(36, 53, 104, 796):
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return PVR_GPU_SUPPORTED;
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+
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+
case PVR_PACKED_BVNC(36, 52, 104, 182):
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return PVR_GPU_EXPERIMENTAL;
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+
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default:
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return PVR_GPU_UNKNOWN;
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+
}
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+
}
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+
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static int
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+
pvr_check_gpu_supported(struct pvr_device *pvr_dev,
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const struct pvr_gpu_id *gpu_id)
565
+
{
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struct drm_device *drm_dev = from_pvr_device(pvr_dev);
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+
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+
switch (pvr_gpu_support_level(gpu_id)) {
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case PVR_GPU_SUPPORTED:
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if (pvr_exp_hw_support)
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drm_info(drm_dev, "Module parameter 'exp_hw_support' was set, but this hardware is fully supported by the current driver.");
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+
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+
break;
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+
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case PVR_GPU_EXPERIMENTAL:
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if (!pvr_exp_hw_support) {
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+
drm_err(drm_dev, "Unsupported GPU! Set 'exp_hw_support' to bypass this check.");
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return -ENODEV;
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+
}
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+
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drm_warn(drm_dev, "Running on unsupported hardware; you may encounter bugs!");
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+
break;
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+
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+
/* NOTE: This code path may indicate misbehaving hardware. */
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case PVR_GPU_UNKNOWN:
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default:
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if (!pvr_exp_hw_support) {
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drm_err(drm_dev, "Unknown GPU! Set 'exp_hw_support' to bypass this check.");
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+
return -ENODEV;
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+
}
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+
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drm_warn(drm_dev, "Running on unknown hardware; expect issues.");
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+
break;
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+
}
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+
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+
return 0;
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+
}
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+
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static char *pvr_gpuid_override;
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module_param_named(gpuid, pvr_gpuid_override, charp, 0400);
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MODULE_PARM_DESC(gpuid, "GPU ID (BVNC) to be used instead of the value read from hardware.");
···
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return err;
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}
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629
-
return 0;
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+
return pvr_check_gpu_supported(pvr_dev, gpu_id);
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}
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/**