[PATCH 0/4] vc4 RST documentation

[PATCH 0/4] vc4 RST documentation

[Eric Anholt]

danvet asked me a while ago to try generating documentation with the
new RST-based infrastructure.  I had a couple of hours to do some
editing, so here it is.

So far I'm not including any kerneldoc for functions.  I don't think I
have enough documentation coverage yet to make it useful to start
including the current ones in the output.

Eric Anholt (4):
  drm/vc4: Convert existing documentation to actual kerneldoc.
  drm/vc4: Add RST to bring together vc4 kerneldoc.
  drm/vc4: Extend and edit documentation for output from the RST
  drm/vc4: Add a paragraph at the top of vc4 docs introducing what it
    is.

 Documentation/gpu/index.rst                |  1 +
 Documentation/gpu/vc4.rst                  | 89 ++++++++++++++++++++++++++++++
 drivers/gpu/drm/vc4/vc4_bo.c               |  5 +-
 drivers/gpu/drm/vc4/vc4_crtc.c             |  7 ++-
 drivers/gpu/drm/vc4/vc4_dpi.c              |  3 +-
 drivers/gpu/drm/vc4/vc4_drv.c              | 16 ++++++
 drivers/gpu/drm/vc4/vc4_dsi.c              |  5 +-
 drivers/gpu/drm/vc4/vc4_gem.c              | 26 +++++++--
 drivers/gpu/drm/vc4/vc4_hdmi.c             | 23 +++++++-
 drivers/gpu/drm/vc4/vc4_hvs.c              | 12 ++--
 drivers/gpu/drm/vc4/vc4_irq.c              |  3 +-
 drivers/gpu/drm/vc4/vc4_render_cl.c        |  4 ++
 drivers/gpu/drm/vc4/vc4_validate.c         | 34 +++++++-----
 drivers/gpu/drm/vc4/vc4_validate_shaders.c | 21 ++++---
 drivers/gpu/drm/vc4/vc4_vec.c              |  6 ++
 15 files changed, 212 insertions(+), 43 deletions(-)
 create mode 100644 Documentation/gpu/vc4.rst

-- 
2.11.0

[PATCH 1/4] drm/vc4: Convert existing documentation to actual kerneldoc.

[Eric Anholt]

I'm going to hook vc4 up to the sphinx build, so clean up its comments
to not generate warnings when we do.

Signed-off-by: Eric Anholt <eric@anholt.net>
---
 drivers/gpu/drm/vc4/vc4_bo.c       |  5 ++++-
 drivers/gpu/drm/vc4/vc4_dsi.c      |  5 +++--
 drivers/gpu/drm/vc4/vc4_gem.c      | 26 +++++++++++++++++++++-----
 drivers/gpu/drm/vc4/vc4_irq.c      |  3 ++-
 drivers/gpu/drm/vc4/vc4_validate.c | 10 +++++++---
 5 files changed, 37 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/vc4/vc4_bo.c b/drivers/gpu/drm/vc4/vc4_bo.c
index 3f6704cf6608..7abcd9c5dbe2 100644
--- a/drivers/gpu/drm/vc4/vc4_bo.c
+++ b/drivers/gpu/drm/vc4/vc4_bo.c
@@ -6,7 +6,8 @@
  * published by the Free Software Foundation.
  */
 
-/* DOC: VC4 GEM BO management support.
+/**
+ * DOC: VC4 GEM BO management support
  *
  * The VC4 GPU architecture (both scanout and rendering) has direct
  * access to system memory with no MMU in between.  To support it, we
@@ -186,6 +187,8 @@ static struct vc4_bo *vc4_bo_get_from_cache(struct drm_device *dev,
 
 /**
  * vc4_gem_create_object - Implementation of driver->gem_create_object.
+ * @dev: DRM device
+ * @size: Size in bytes of the memory the object will reference
  *
  * This lets the CMA helpers allocate object structs for us, and keep
  * our BO stats correct.
diff --git a/drivers/gpu/drm/vc4/vc4_dsi.c b/drivers/gpu/drm/vc4/vc4_dsi.c
index e328cb86469c..160f981d1cf4 100644
--- a/drivers/gpu/drm/vc4/vc4_dsi.c
+++ b/drivers/gpu/drm/vc4/vc4_dsi.c
@@ -1453,8 +1453,9 @@ static irqreturn_t vc4_dsi_irq_handler(int irq, void *data)
 }
 
 /**
- * Exposes clocks generated by the analog PHY that are consumed by
- * CPRMAN (clk-bcm2835.c).
+ * vc4_dsi_init_phy_clocks - Exposes clocks generated by the analog
+ * PHY that are consumed by CPRMAN (clk-bcm2835.c).
+ * @dsi: DSI encoder
  */
 static int
 vc4_dsi_init_phy_clocks(struct vc4_dsi *dsi)
diff --git a/drivers/gpu/drm/vc4/vc4_gem.c b/drivers/gpu/drm/vc4/vc4_gem.c
index db920771bfb5..79f0099d17d0 100644
--- a/drivers/gpu/drm/vc4/vc4_gem.c
+++ b/drivers/gpu/drm/vc4/vc4_gem.c
@@ -511,9 +511,18 @@ vc4_queue_submit(struct drm_device *dev, struct vc4_exec_info *exec)
 }
 
 /**
- * Looks up a bunch of GEM handles for BOs and stores the array for
- * use in the command validator that actually writes relocated
- * addresses pointing to them.
+ * vc4_cl_lookup_bos() - Sets up exec->bo[] with the GEM objects
+ * referenced by the job.
+ * @dev: DRM device
+ * @file_priv: DRM file for this fd
+ * @exec: V3D job being set up
+ *
+ * The command validator needs to reference BOs by their index within
+ * the submitted job's BO list.  This does the validation of the job's
+ * BO list and reference counting for the lifetime of the job.
+ *
+ * Note that this function doesn't need to unreference the BOs on
+ * failure, because that will happen at vc4_complete_exec() time.
  */
 static int
 vc4_cl_lookup_bos(struct drm_device *dev,
@@ -844,9 +853,16 @@ vc4_wait_bo_ioctl(struct drm_device *dev, void *data,
 }
 
 /**
- * Submits a command list to the VC4.
+ * vc4_submit_cl_ioctl() - Submits a job (frame) to the VC4.
+ * @dev: DRM device
+ * @data: ioctl argument
+ * @file_priv: DRM file for this fd
  *
- * This is what is called batchbuffer emitting on other hardware.
+ * This is the main entrypoint for userspace to submit a 3D frame to
+ * the GPU.  Userspace provides the binner command list (if
+ * applicable), and the kernel sets up the render command list to draw
+ * to the framebuffer described in the ioctl, using the command lists
+ * that the 3D engine's binner will produce.
  */
 int
 vc4_submit_cl_ioctl(struct drm_device *dev, void *data,
diff --git a/drivers/gpu/drm/vc4/vc4_irq.c b/drivers/gpu/drm/vc4/vc4_irq.c
index 094bc6a475c1..cdc6e6760705 100644
--- a/drivers/gpu/drm/vc4/vc4_irq.c
+++ b/drivers/gpu/drm/vc4/vc4_irq.c
@@ -21,7 +21,8 @@
  * IN THE SOFTWARE.
  */
 
-/** DOC: Interrupt management for the V3D engine.
+/**
+ * DOC: Interrupt management for the V3D engine
  *
  * We have an interrupt status register (V3D_INTCTL) which reports
  * interrupts, and where writing 1 bits clears those interrupts.
diff --git a/drivers/gpu/drm/vc4/vc4_validate.c b/drivers/gpu/drm/vc4/vc4_validate.c
index 9fd171c361c2..d696ed49e9f0 100644
--- a/drivers/gpu/drm/vc4/vc4_validate.c
+++ b/drivers/gpu/drm/vc4/vc4_validate.c
@@ -22,7 +22,7 @@
  */
 
 /**
- * Command list validator for VC4.
+ * DOC: Command list validator for VC4.
  *
  * The VC4 has no IOMMU between it and system memory.  So, a user with
  * access to execute command lists could escalate privilege by
@@ -84,8 +84,12 @@ utile_height(int cpp)
 }
 
 /**
- * The texture unit decides what tiling format a particular miplevel is using
- * this function, so we lay out our miptrees accordingly.
+ * size_is_lt() - Returns whether a miplevel of the given size will
+ * use the lineartile (LT) tiling layout rather than the normal T
+ * tiling layout.
+ * @width: Width in pixels of the miplevel
+ * @height: Height in pixels of the miplevel
+ * @cpp: Bytes per pixel of the pixel format
  */
 static bool
 size_is_lt(uint32_t width, uint32_t height, int cpp)
-- 
2.11.0

[PATCH 2/4] drm/vc4: Add RST to bring together vc4 kerneldoc.

[Eric Anholt]

This doesn't yet produce coherent documentation of the module, but at
least gets the kerneldoc built and somewhat glued together.

Signed-off-by: Eric Anholt <eric@anholt.net>
---
 Documentation/gpu/index.rst |  1 +
 Documentation/gpu/vc4.rst   | 86 +++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 87 insertions(+)
 create mode 100644 Documentation/gpu/vc4.rst

diff --git a/Documentation/gpu/index.rst b/Documentation/gpu/index.rst
index c9b08b02f57c..8effecb947a6 100644
--- a/Documentation/gpu/index.rst
+++ b/Documentation/gpu/index.rst
@@ -11,6 +11,7 @@ Linux GPU Driver Developer's Guide
    drm-kms-helpers
    drm-uapi
    i915
+   vc4
    vga-switcheroo
    vgaarbiter
    todo
diff --git a/Documentation/gpu/vc4.rst b/Documentation/gpu/vc4.rst
new file mode 100644
index 000000000000..b06117b5d495
--- /dev/null
+++ b/Documentation/gpu/vc4.rst
@@ -0,0 +1,86 @@
+=====================================
+ drm/vc4 Broadcom VC4 Graphics Driver
+=====================================
+
+Display Hardware Handling
+=========================
+
+This section covers everything related to the display hardware including
+the mode setting infrastructure, plane, sprite and cursor handling and
+display, output probing and related topics.
+
+Pixel Valve (DRM CRTC)
+----------------------
+
+.. kernel-doc:: drivers/gpu/drm/vc4/vc4_crtc.c
+   :doc: VC4 CRTC module
+
+HVS
+---
+
+.. kernel-doc:: drivers/gpu/drm/vc4/vc4_hvs.c
+   :doc: VC4 HVS module.
+
+HVS planes
+----------
+
+.. kernel-doc:: drivers/gpu/drm/vc4/vc4_plane.c
+   :doc: VC4 plane module
+
+HDMI encoder
+------------
+
+.. kernel-doc:: drivers/gpu/drm/vc4/vc4_hdmi.c
+   :doc: VC4 Falcon HDMI module
+
+DSI encoder
+-----------
+
+.. kernel-doc:: drivers/gpu/drm/vc4/vc4_dsi.c
+   :doc: VC4 DSI0/DSI1 module
+
+DPI encoder
+-----------
+
+.. kernel-doc:: drivers/gpu/drm/vc4/vc4_dpi.c
+   :doc: VC4 DPI module
+
+VEC (Composite TV out) encoder
+------------------------------
+
+.. kernel-doc:: drivers/gpu/drm/vc4/vc4_vec.c
+   :doc: VC4 SDTV module
+
+Memory Management and 3D Command Submission
+===========================================
+
+This section covers the GEM implementation in the vc4 driver.
+
+GPU buffer object (BO) management
+---------------------------------
+
+.. kernel-doc:: drivers/gpu/drm/vc4/vc4_bo.c
+   :doc: VC4 GEM BO management support
+
+V3D binner command list (BCL) validation
+----------------------------------------
+
+.. kernel-doc:: drivers/gpu/drm/vc4/vc4_validate.c
+   :doc: Command list validator for VC4.
+
+V3D render command list (RCL) generation
+----------------------------------------
+
+.. kernel-doc:: drivers/gpu/drm/vc4/vc4_render_cl.c
+   :doc: Render command list generation
+
+Shader validator for VC4
+---------------------------
+.. kernel-doc:: drivers/gpu/drm/vc4/vc4_validate_shaders.c
+   :doc: Shader validator for VC4.
+
+V3D Interrupts
+--------------
+
+.. kernel-doc:: drivers/gpu/drm/vc4/vc4_irq.c
+   :doc: Interrupt management for the V3D engine
-- 
2.11.0

[PATCH 3/4] drm/vc4: Extend and edit documentation for output from the RST

[Eric Anholt]

I had written most of my comments as if I was describing the
individual code files the way I used to for doxygen, while for RST we
want to describe things in a more chapter/section way where there's no
obvious relation to .c files.

Additionally, several of the files had stub descriptions that I've
taken this opportunity to extend.

Signed-off-by: Eric Anholt <eric@anholt.net>
---
 drivers/gpu/drm/vc4/vc4_crtc.c             |  7 ++++---
 drivers/gpu/drm/vc4/vc4_dpi.c              |  3 ++-
 drivers/gpu/drm/vc4/vc4_hdmi.c             | 23 ++++++++++++++++++++---
 drivers/gpu/drm/vc4/vc4_hvs.c              | 12 ++++++------
 drivers/gpu/drm/vc4/vc4_render_cl.c        |  4 ++++
 drivers/gpu/drm/vc4/vc4_validate.c         | 24 ++++++++++++++----------
 drivers/gpu/drm/vc4/vc4_validate_shaders.c | 21 +++++++++++++--------
 drivers/gpu/drm/vc4/vc4_vec.c              |  6 ++++++
 8 files changed, 69 insertions(+), 31 deletions(-)

diff --git a/drivers/gpu/drm/vc4/vc4_crtc.c b/drivers/gpu/drm/vc4/vc4_crtc.c
index 764320156cce..7fa4c3d5cddf 100644
--- a/drivers/gpu/drm/vc4/vc4_crtc.c
+++ b/drivers/gpu/drm/vc4/vc4_crtc.c
@@ -11,12 +11,13 @@
  *
  * In VC4, the Pixel Valve is what most closely corresponds to the
  * DRM's concept of a CRTC.  The PV generates video timings from the
- * output's clock plus its configuration.  It pulls scaled pixels from
+ * encoder's clock plus its configuration.  It pulls scaled pixels from
  * the HVS at that timing, and feeds it to the encoder.
  *
  * However, the DRM CRTC also collects the configuration of all the
- * DRM planes attached to it.  As a result, this file also manages
- * setup of the VC4 HVS's display elements on the CRTC.
+ * DRM planes attached to it.  As a result, the CRTC is also
+ * responsible for writing the display list for the HVS channel that
+ * the CRTC will use.
  *
  * The 2835 has 3 different pixel valves.  pv0 in the audio power
  * domain feeds DSI0 or DPI, while pv1 feeds DS1 or SMI.  pv2 in the
diff --git a/drivers/gpu/drm/vc4/vc4_dpi.c b/drivers/gpu/drm/vc4/vc4_dpi.c
index 3f360cf6cf5a..71435796c710 100644
--- a/drivers/gpu/drm/vc4/vc4_dpi.c
+++ b/drivers/gpu/drm/vc4/vc4_dpi.c
@@ -18,7 +18,8 @@
  * DOC: VC4 DPI module
  *
  * The VC4 DPI hardware supports MIPI DPI type 4 and Nokia ViSSI
- * signals, which are routed out to GPIO0-27 with the ALT2 function.
+ * signals.  On BCM2835, these can be routed out to GPIO0-27 with the
+ * ALT2 function.
  */
 
 #include "drm_atomic_helper.h"
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index 93d5994f3a04..1be1e8304720 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -20,9 +20,26 @@
 /**
  * DOC: VC4 Falcon HDMI module
  *
- * The HDMI core has a state machine and a PHY.  Most of the unit
- * operates off of the HSM clock from CPRMAN.  It also internally uses
- * the PLLH_PIX clock for the PHY.
+ * The HDMI core has a state machine and a PHY.  On BCM2835, most of
+ * the unit operates off of the HSM clock from CPRMAN.  It also
+ * internally uses the PLLH_PIX clock for the PHY.
+ *
+ * HDMI infoframes are kept within a small packet ram, where each
+ * packet can be individually enabled for including in a frame.
+ *
+ * HDMI audio is implemented entirely within the HDMI IP block.  A
+ * register in the HDMI encoder takes SPDIF frames from the DMA engine
+ * and transfers them over an internal MAI (multi-channel audio
+ * interconnect) bus to the encoder side for insertion into the video
+ * blank regions.
+ *
+ * The driver's HDMI encoder does not yet support power management.
+ * The HDMI encoder's power domain and the HSM/pixel clocks are kept
+ * continuously running, and only the HDMI logic and packet ram are
+ * powered off/on at disable/enable time.
+ *
+ * The driver does not yet support CEC control, though the HDMI
+ * encoder block has CEC support.
  */
 
 #include "drm_atomic_helper.h"
diff --git a/drivers/gpu/drm/vc4/vc4_hvs.c b/drivers/gpu/drm/vc4/vc4_hvs.c
index f7f7677f6d8d..fd421ba3c5d7 100644
--- a/drivers/gpu/drm/vc4/vc4_hvs.c
+++ b/drivers/gpu/drm/vc4/vc4_hvs.c
@@ -9,12 +9,12 @@
 /**
  * DOC: VC4 HVS module.
  *
- * The HVS is the piece of hardware that does translation, scaling,
- * colorspace conversion, and compositing of pixels stored in
- * framebuffers into a FIFO of pixels going out to the Pixel Valve
- * (CRTC).  It operates at the system clock rate (the system audio
- * clock gate, specifically), which is much higher than the pixel
- * clock rate.
+ * The Hardware Video Scaler (HVS) is the piece of hardware that does
+ * translation, scaling, colorspace conversion, and compositing of
+ * pixels stored in framebuffers into a FIFO of pixels going out to
+ * the Pixel Valve (CRTC).  It operates at the system clock rate (the
+ * system audio clock gate, specifically), which is much higher than
+ * the pixel clock rate.
  *
  * There is a single global HVS, with multiple output FIFOs that can
  * be consumed by the PVs.  This file just manages the resources for
diff --git a/drivers/gpu/drm/vc4/vc4_render_cl.c b/drivers/gpu/drm/vc4/vc4_render_cl.c
index 08886a309757..8fc2fb461ac3 100644
--- a/drivers/gpu/drm/vc4/vc4_render_cl.c
+++ b/drivers/gpu/drm/vc4/vc4_render_cl.c
@@ -24,6 +24,10 @@
 /**
  * DOC: Render command list generation
  *
+ * In the V3D hardware, render command lists are what load and store
+ * tiles of a framebuffer and optionally call out to binner-generated
+ * command lists to do the 3D drawing for that tile.
+ *
  * In the VC4 driver, render command list generation is performed by the
  * kernel instead of userspace.  We do this because validating a
  * user-submitted command list is hard to get right and has high CPU overhead,
diff --git a/drivers/gpu/drm/vc4/vc4_validate.c b/drivers/gpu/drm/vc4/vc4_validate.c
index d696ed49e9f0..da6f1e138e8d 100644
--- a/drivers/gpu/drm/vc4/vc4_validate.c
+++ b/drivers/gpu/drm/vc4/vc4_validate.c
@@ -24,19 +24,23 @@
 /**
  * DOC: Command list validator for VC4.
  *
- * The VC4 has no IOMMU between it and system memory.  So, a user with
- * access to execute command lists could escalate privilege by
+ * Since the VC4 has no IOMMU between it and system memory, a user
+ * with access to execute command lists could escalate privilege by
  * overwriting system memory (drawing to it as a framebuffer) or
- * reading system memory it shouldn't (reading it as a texture, or
- * uniform data, or vertex data).
+ * reading system memory it shouldn't (reading it as a vertex buffer
+ * or index buffer)
  *
- * This validates command lists to ensure that all accesses are within
- * the bounds of the GEM objects referenced.  It explicitly whitelists
- * packets, and looks at the offsets in any address fields to make
- * sure they're constrained within the BOs they reference.
+ * We validate binner command lists to ensure that all accesses are
+ * within the bounds of the GEM objects referenced by the submitted
+ * job.  It explicitly whitelists packets, and looks at the offsets in
+ * any address fields to make sure they're contained within the BOs
+ * they reference.
  *
- * Note that because of the validation that's happening anyway, this
- * is where GEM relocation processing happens.
+ * Note that because CL validation is already reading the
+ * user-submitted CL and writing the validated copy out to the memory
+ * that the GPU will actually read, this is also where GEM relocation
+ * processing (turning BO references into actual addresses for the GPU
+ * to use) happens.
  */
 
 #include "uapi/drm/vc4_drm.h"
diff --git a/drivers/gpu/drm/vc4/vc4_validate_shaders.c b/drivers/gpu/drm/vc4/vc4_validate_shaders.c
index 5dba13dd1e9b..0b2df5c6efb4 100644
--- a/drivers/gpu/drm/vc4/vc4_validate_shaders.c
+++ b/drivers/gpu/drm/vc4/vc4_validate_shaders.c
@@ -24,16 +24,21 @@
 /**
  * DOC: Shader validator for VC4.
  *
- * The VC4 has no IOMMU between it and system memory, so a user with
- * access to execute shaders could escalate privilege by overwriting
- * system memory (using the VPM write address register in the
- * general-purpose DMA mode) or reading system memory it shouldn't
- * (reading it as a texture, or uniform data, or vertex data).
+ * Since the VC4 has no IOMMU between it and system memory, a user
+ * with access to execute shaders could escalate privilege by
+ * overwriting system memory (using the VPM write address register in
+ * the general-purpose DMA mode) or reading system memory it shouldn't
+ * (reading it as a texture, uniform data, or direct-addressed TMU
+ * lookup).
  *
- * This walks over a shader BO, ensuring that its accesses are
- * appropriately bounded, and recording how many texture accesses are
- * made and where so that we can do relocations for them in the
+ * The shader validator walks over a shader's BO, ensuring that its
+ * accesses are appropriately bounded, and recording where texture
+ * accesses are made so that we can do relocations for them in the
  * uniform stream.
+ *
+ * Shader BO are immutable for their lifetimes (enforced by not
+ * allowing mmaps, GEM prime export, or rendering to from a CL), so
+ * this validation is only performed at BO creation time.
  */
 
 #include "vc4_drv.h"
diff --git a/drivers/gpu/drm/vc4/vc4_vec.c b/drivers/gpu/drm/vc4/vc4_vec.c
index 32bb8ef985fb..09c1e05765fa 100644
--- a/drivers/gpu/drm/vc4/vc4_vec.c
+++ b/drivers/gpu/drm/vc4/vc4_vec.c
@@ -16,6 +16,12 @@
 
 /**
  * DOC: VC4 SDTV module
+ *
+ * The VEC encoder generates PAL or NTSC composite video output.
+ *
+ * TV mode selection is done by an atomic property on the encoder,
+ * because a drm_mode_modeinfo is insufficient to distinguish between
+ * PAL and PAL-M or NTSC and NTSC-J.
  */
 
 #include <drm/drm_atomic_helper.h>
-- 
2.11.0

[PATCH 4/4] drm/vc4: Add a paragraph at the top of vc4 docs introducing what it is.

[Eric Anholt]

This makes for more sensible documentation of the whole module than
jumping straight into the details of display.

Signed-off-by: Eric Anholt <eric@anholt.net>
---
 Documentation/gpu/vc4.rst     |  3 +++
 drivers/gpu/drm/vc4/vc4_drv.c | 16 ++++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/Documentation/gpu/vc4.rst b/Documentation/gpu/vc4.rst
index b06117b5d495..5df1d98b9544 100644
--- a/Documentation/gpu/vc4.rst
+++ b/Documentation/gpu/vc4.rst
@@ -2,6 +2,9 @@
  drm/vc4 Broadcom VC4 Graphics Driver
 =====================================
 
+.. kernel-doc:: drivers/gpu/drm/vc4/vc4_drv.c
+   :doc: Broadcom VC4 Graphics Driver
+
 Display Hardware Handling
 =========================
 
diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c
index 4f93328a2f20..205c1961ffb4 100644
--- a/drivers/gpu/drm/vc4/vc4_drv.c
+++ b/drivers/gpu/drm/vc4/vc4_drv.c
@@ -7,6 +7,22 @@
  * published by the Free Software Foundation.
  */
 
+/**
+ * DOC: Broadcom VC4 Graphics Driver
+ *
+ * The Broadcom VideoCore 4 (present in the Raspberry Pi) contains a
+ * OpenGL ES 2.0-compatible 3D engine called V3D, and a highly
+ * configurable display output pipeline that supports HDMI, DSI, DPI,
+ * and Composite TV output.
+ *
+ * The 3D engine also has an interface for submitting arbitrary
+ * compute shader-style jobs using the same shader processor as is
+ * used for vertex and fragment shaders in GLES 2.0.  However, given
+ * that the hardware isn't able to expose any standard interfaces like
+ * OpenGL compute shaders or OpenCL, it isn't supported by this
+ * driver.
+ */
+
 #include <linux/clk.h>
 #include <linux/component.h>
 #include <linux/device.h>
-- 
2.11.0

Re: [PATCH 0/4] vc4 RST documentation

[Daniel Vetter]

On Mon, Feb 27, 2017 at 12:11:40PM -0800, Eric Anholt wrote:
> danvet asked me a while ago to try generating documentation with the
> new RST-based infrastructure.  I had a couple of hours to do some
> editing, so here it is.
> 
> So far I'm not including any kerneldoc for functions.  I don't think I
> have enough documentation coverage yet to make it useful to start
> including the current ones in the output.
> 
> Eric Anholt (4):
>   drm/vc4: Convert existing documentation to actual kerneldoc.
>   drm/vc4: Add RST to bring together vc4 kerneldoc.
>   drm/vc4: Extend and edit documentation for output from the RST
>   drm/vc4: Add a paragraph at the top of vc4 docs introducing what it
>     is.

Wooohooooo, this is sweet! I know it's just a rough just, but I think i915
is even rougher, and we just need to get going somewhere. Really awesome.
On the series:

Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> 
>  Documentation/gpu/index.rst                |  1 +
>  Documentation/gpu/vc4.rst                  | 89 ++++++++++++++++++++++++++++++
>  drivers/gpu/drm/vc4/vc4_bo.c               |  5 +-
>  drivers/gpu/drm/vc4/vc4_crtc.c             |  7 ++-
>  drivers/gpu/drm/vc4/vc4_dpi.c              |  3 +-
>  drivers/gpu/drm/vc4/vc4_drv.c              | 16 ++++++
>  drivers/gpu/drm/vc4/vc4_dsi.c              |  5 +-
>  drivers/gpu/drm/vc4/vc4_gem.c              | 26 +++++++--
>  drivers/gpu/drm/vc4/vc4_hdmi.c             | 23 +++++++-
>  drivers/gpu/drm/vc4/vc4_hvs.c              | 12 ++--
>  drivers/gpu/drm/vc4/vc4_irq.c              |  3 +-
>  drivers/gpu/drm/vc4/vc4_render_cl.c        |  4 ++
>  drivers/gpu/drm/vc4/vc4_validate.c         | 34 +++++++-----
>  drivers/gpu/drm/vc4/vc4_validate_shaders.c | 21 ++++---
>  drivers/gpu/drm/vc4/vc4_vec.c              |  6 ++
>  15 files changed, 212 insertions(+), 43 deletions(-)
>  create mode 100644 Documentation/gpu/vc4.rst
> 
> -- 
> 2.11.0
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

Re: [PATCH 0/4] vc4 RST documentation

[Eric Anholt]

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Daniel Vetter <daniel@ffwll.ch> writes:

> On Mon, Feb 27, 2017 at 12:11:40PM -0800, Eric Anholt wrote:
>> danvet asked me a while ago to try generating documentation with the
>> new RST-based infrastructure.  I had a couple of hours to do some
>> editing, so here it is.
>> 
>> So far I'm not including any kerneldoc for functions.  I don't think I
>> have enough documentation coverage yet to make it useful to start
>> including the current ones in the output.
>> 
>> Eric Anholt (4):
>>   drm/vc4: Convert existing documentation to actual kerneldoc.
>>   drm/vc4: Add RST to bring together vc4 kerneldoc.
>>   drm/vc4: Extend and edit documentation for output from the RST
>>   drm/vc4: Add a paragraph at the top of vc4 docs introducing what it
>>     is.
>
> Wooohooooo, this is sweet! I know it's just a rough just, but I think i915
> is even rougher, and we just need to get going somewhere. Really awesome.
> On the series:
>
> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Getting started on this was easy enough, I'm definitely hoping to do
more.

Applied the ack and pushed.  Thanks!

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