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git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Documentation/amdgpu: Add UMA carveout details
Add documentation for the uma/carveout_options and uma/carveout
attributes in sysfs
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Yo-Jung Leo Lin (AMD) <Leo.Lin@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
authored by
Yo-Jung Leo Lin (AMD)
and committed by
Alex Deucher
5946dbe1
19ba61ac
+55
+26
Documentation/gpu/amdgpu/driver-misc.rst
+26
Documentation/gpu/amdgpu/driver-misc.rst
···
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.. kernel-doc:: drivers/gpu/drm/amd/pm/amdgpu_pm.c
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:doc: smartshift_bias
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UMA Carveout
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============
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Some versions of Atom ROM expose available options for the VRAM carveout sizes,
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and allow changes to the carveout size via the ATCS function code 0xA on supported
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BIOS implementations.
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For those platforms, users can use the following files under uma/ to set the
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carveout size, in a way similar to what Windows users can do in the "Tuning"
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tab in AMD Adrenalin.
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Note that for BIOS implementations that don't support this, these files will not
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be created at all.
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uma/carveout_options
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--------------------
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.. kernel-doc:: drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
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:doc: uma/carveout_options
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uma/carveout
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--------------------
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.. kernel-doc:: drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
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:doc: uma/carveout
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drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
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drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
···
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.is_visible = amdgpu_board_attrs_is_visible
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};
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/**
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* DOC: uma/carveout_options
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*
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* This is a read-only file that lists all available UMA allocation
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* options and their corresponding indices. Example output::
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*
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* $ cat uma/carveout_options
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* 0: Minimum (512 MB)
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* 1: (1 GB)
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* 2: (2 GB)
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* 3: (4 GB)
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* 4: (6 GB)
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* 5: (8 GB)
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* 6: (12 GB)
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* 7: Medium (16 GB)
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* 8: (24 GB)
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* 9: High (32 GB)
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*/
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static ssize_t carveout_options_show(struct device *dev,
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struct device_attribute *attr,
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char *buf)
···
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}
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static DEVICE_ATTR_RO(carveout_options);
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/**
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* DOC: uma/carveout
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*
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* This file is both readable and writable. When read, it shows the
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* index of the current setting. Writing a valid index to this file
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* allows users to change the UMA carveout size to the selected option
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* on the next boot.
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*
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* The available options and their corresponding indices can be read
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* from the uma/carveout_options file.
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*/
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static ssize_t carveout_show(struct device *dev,
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struct device_attribute *attr,
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char *buf)