[Intel-gfx] [PATCH 3/8] drm/i915/huc: Add HuC fw loading support

Jeff McGee jeff.mcgee at intel.com
Thu Oct 13 17:42:42 UTC 2016


On Mon, Oct 03, 2016 at 11:42:57AM -0700, Anusha Srivatsa wrote:
> From: Peter Antoine <peter.antoine at intel.com>
> 
> The HuC loading process is similar to GuC. The intel_uc_fw_fetch()
> is used for both cases.
> 
> HuC loading needs to be before GuC loading. The WOPCM setting must
> be done early before loading any of them.
> 
> v2: rebased on-top of drm-intel-nightly.
>     removed if(HAS_GUC()) before the guc call. (D.Gordon)
>     update huc_version number of format.
> v3: rebased to drm-intel-nightly, changed the file name format to
>     match the one in the huc package.
>     Changed dev->dev_private to to_i915()
> v4: moved function back to where it was.
>     change wait_for_atomic to wait_for.
> v5: rebased + comment changes.
> v7: rebased.
> v8: rebased.
> 
> Tested-by: Xiang Haihao <haihao.xiang at intel.com>
> Signed-off-by: Anusha Srivatsa <anusha.srivatsa at intel.com>
> Signed-off-by: Alex Dai <yu.dai at intel.com>
> Signed-off-by: Peter Antoine <peter.antoine at intel.com>
> Reviewed-by: Dave Gordon <david.s.gordon at intel.com>
> ---
>  drivers/gpu/drm/i915/Makefile           |   1 +
>  drivers/gpu/drm/i915/i915_drv.c         |   3 +
>  drivers/gpu/drm/i915/i915_drv.h         |   3 +
>  drivers/gpu/drm/i915/i915_guc_reg.h     |   3 +
>  drivers/gpu/drm/i915/intel_guc.h        |   1 +
>  drivers/gpu/drm/i915/intel_guc_loader.c |   6 +-
>  drivers/gpu/drm/i915/intel_huc.h        |  44 ++++++
>  drivers/gpu/drm/i915/intel_huc_loader.c | 268 ++++++++++++++++++++++++++++++++
>  8 files changed, 327 insertions(+), 2 deletions(-)
>  create mode 100644 drivers/gpu/drm/i915/intel_huc.h
>  create mode 100644 drivers/gpu/drm/i915/intel_huc_loader.c
> 
> diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
> index e6fe004..6e99c51 100644
> --- a/drivers/gpu/drm/i915/Makefile
> +++ b/drivers/gpu/drm/i915/Makefile
> @@ -53,6 +53,7 @@ i915-y += i915_cmd_parser.o \
>  
>  # general-purpose microcontroller (GuC) support
>  i915-y += intel_guc_loader.o \
> +	  intel_huc_loader.o \
>  	  i915_guc_submission.o
>  
>  # autogenerated null render state
> diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
> index 31b2b63..7af7bd6 100644
> --- a/drivers/gpu/drm/i915/i915_drv.c
> +++ b/drivers/gpu/drm/i915/i915_drv.c
> @@ -613,6 +613,7 @@ static int i915_load_modeset_init(struct drm_device *dev)
>  	 * working irqs for e.g. gmbus and dp aux transfers. */
>  	intel_modeset_init(dev);
>  
> +	intel_huc_init(dev);
>  	intel_guc_init(dev);
>  
>  	ret = i915_gem_init(dev);
> @@ -638,6 +639,7 @@ static int i915_load_modeset_init(struct drm_device *dev)
>  cleanup_gem:
>  	i915_gem_fini(dev);
>  cleanup_irq:
> +	intel_huc_fini(dev);
>  	intel_guc_fini(dev);
>  	drm_irq_uninstall(dev);
>  	intel_teardown_gmbus(dev);
> @@ -1315,6 +1317,7 @@ void i915_driver_unload(struct drm_device *dev)
>  	/* Flush any outstanding unpin_work. */
>  	drain_workqueue(dev_priv->wq);
>  
> +	intel_huc_fini(dev);
>  	intel_guc_fini(dev);
>  	i915_gem_fini(dev);
>  	intel_fbc_cleanup_cfb(dev_priv);
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index e0cb71c..625aa92 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -55,6 +55,7 @@
>  #include "intel_bios.h"
>  #include "intel_dpll_mgr.h"
>  #include "intel_guc.h"
> +#include "intel_huc.h"
>  #include "intel_lrc.h"
>  #include "intel_ringbuffer.h"
>  
> @@ -1766,6 +1767,7 @@ struct drm_i915_private {
>  
>  	struct intel_gvt gvt;
>  
> +	struct intel_huc huc;
>  	struct intel_guc guc;
>  
>  	struct intel_csr csr;
> @@ -2822,6 +2824,7 @@ struct drm_i915_cmd_table {
>  #define HAS_GUC(dev)		(INTEL_INFO(dev)->has_guc)
>  #define HAS_GUC_UCODE(dev)	(HAS_GUC(dev))
>  #define HAS_GUC_SCHED(dev)	(HAS_GUC(dev))
> +#define HAS_HUC_UCODE(dev)	(HAS_GUC(dev))
>  
>  #define HAS_RESOURCE_STREAMER(dev) (INTEL_INFO(dev)->has_resource_streamer)
>  
> diff --git a/drivers/gpu/drm/i915/i915_guc_reg.h b/drivers/gpu/drm/i915/i915_guc_reg.h
> index a47e1e4..64e942a 100644
> --- a/drivers/gpu/drm/i915/i915_guc_reg.h
> +++ b/drivers/gpu/drm/i915/i915_guc_reg.h
> @@ -61,9 +61,12 @@
>  #define   DMA_ADDRESS_SPACE_GTT		  (8 << 16)
>  #define DMA_COPY_SIZE			_MMIO(0xc310)
>  #define DMA_CTRL			_MMIO(0xc314)
> +#define   HUC_UKERNEL			  (1<<9)
>  #define   UOS_MOVE			  (1<<4)
>  #define   START_DMA			  (1<<0)
>  #define DMA_GUC_WOPCM_OFFSET		_MMIO(0xc340)
> +#define   HUC_LOADING_AGENT_VCR		  (0<<1)
> +#define   HUC_LOADING_AGENT_GUC		  (1<<1)
>  #define   GUC_WOPCM_OFFSET_VALUE	  0x80000	/* 512KB */
>  #define GUC_MAX_IDLE_COUNT		_MMIO(0xC3E4)
>  
> diff --git a/drivers/gpu/drm/i915/intel_guc.h b/drivers/gpu/drm/i915/intel_guc.h
> index 812e4ca..af76ffe 100644
> --- a/drivers/gpu/drm/i915/intel_guc.h
> +++ b/drivers/gpu/drm/i915/intel_guc.h
> @@ -160,6 +160,7 @@ extern const char *intel_uc_fw_status_repr(enum intel_uc_fw_status status);
>  extern int intel_guc_suspend(struct drm_device *dev);
>  extern int intel_guc_resume(struct drm_device *dev);
>  void intel_uc_fw_fetch(struct drm_device *dev, struct intel_uc_fw *uc_fw);
> +u32 guc_wopcm_size(struct drm_i915_private *dev_priv);
>  
>  /* i915_guc_submission.c */
>  int i915_guc_submission_init(struct drm_i915_private *dev_priv);
> diff --git a/drivers/gpu/drm/i915/intel_guc_loader.c b/drivers/gpu/drm/i915/intel_guc_loader.c
> index 0b863a1..0d214b4 100644
> --- a/drivers/gpu/drm/i915/intel_guc_loader.c
> +++ b/drivers/gpu/drm/i915/intel_guc_loader.c
> @@ -305,7 +305,8 @@ static int guc_ucode_xfer_dma(struct drm_i915_private *dev_priv,
>  	I915_WRITE(DMA_ADDR_1_HIGH, DMA_ADDRESS_SPACE_WOPCM);
>  
>  	/* Finally start the DMA */
> -	I915_WRITE(DMA_CTRL, _MASKED_BIT_ENABLE(UOS_MOVE | START_DMA));
> +	I915_WRITE(DMA_CTRL, _MASKED_BIT_ENABLE(UOS_MOVE | START_DMA) |
> +			_MASKED_BIT_DISABLE(HUC_UKERNEL));
>  
>  	/*
>  	 * Wait for the DMA to complete & the GuC to start up.
> @@ -330,7 +331,7 @@ static int guc_ucode_xfer_dma(struct drm_i915_private *dev_priv,
>  	return ret;
>  }
>  
> -static u32 guc_wopcm_size(struct drm_i915_private *dev_priv)
> +u32 guc_wopcm_size(struct drm_i915_private *dev_priv)
>  {
>  	u32 wopcm_size = GUC_WOPCM_TOP;
>  
> @@ -508,6 +509,7 @@ int intel_guc_setup(struct drm_device *dev)
>  		if (err)
>  			goto fail;
>  
> +		intel_huc_load(dev);
>  		err = guc_ucode_xfer(dev_priv);
>  		if (!err)
>  			break;
> diff --git a/drivers/gpu/drm/i915/intel_huc.h b/drivers/gpu/drm/i915/intel_huc.h
> new file mode 100644
> index 0000000..946caa7
> --- /dev/null
> +++ b/drivers/gpu/drm/i915/intel_huc.h
> @@ -0,0 +1,44 @@
> +/*
> + * Copyright © 2014 Intel Corporation

Should this be 2016?

> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice (including the next
> + * paragraph) shall be included in all copies or substantial portions of the
> + * Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
> + * IN THE SOFTWARE.
> + *
> + */
> +#ifndef _INTEL_HUC_H_
> +#define _INTEL_HUC_H_
> +
> +#include "intel_guc.h"
> +
> +#define HUC_STATUS2		_MMIO(0xD3B0)
> +#define   HUC_FW_VERIFIED	(1<<7)
> +
> +struct intel_huc {
> +	/* Generic uC firmware management */
> +	struct intel_uc_fw huc_fw;
> +
> +	/* HuC-specific additions */
> +};
> +
> +extern void intel_huc_init(struct drm_device *dev);
> +extern int intel_huc_load(struct drm_device *dev);
> +extern void intel_huc_auth(struct drm_device *dev);
> +extern void intel_huc_fini(struct drm_device *dev);
> +
> +#endif
> diff --git a/drivers/gpu/drm/i915/intel_huc_loader.c b/drivers/gpu/drm/i915/intel_huc_loader.c
> new file mode 100644
> index 0000000..1aaff67
> --- /dev/null
> +++ b/drivers/gpu/drm/i915/intel_huc_loader.c
> @@ -0,0 +1,268 @@
> +/*
> + * Copyright © 2014 Intel Corporation

Should this be 2016?

> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice (including the next
> + * paragraph) shall be included in all copies or substantial portions of the
> + * Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
> + * IN THE SOFTWARE.
> + *
> + */
> +#include <linux/firmware.h>
> +#include "i915_drv.h"
> +#include "intel_huc.h"
> +
> +/**
> + * DOC: HuC Firmware
> + *
> + * Motivation:
> + * GEN9 introduces a new dedicated firmware for usage in media HEVC (High
> + * Efficiency Video Coding) operations. Userspace can use the firmware
> + * capabilities by adding HuC specific commands to batch buffers.
> + *
> + * Implementation:
> + * On supported platforms, i915's job is to load the firmware stored on the
> + * file system and assist with authentication. It is up to userspace to
> + * detect the presence of HuC support on a platform, on their own.
> + * For debugging, i915 provides a debugfs file, i915_huc_load_status_info
> + * which displays the firmware load status.
Above comment refers to features added in subsequent patches and is not
entirely accurate at that. So I would just remove this whole block. Less
commenting is better than misleading commenting.

> + *
> + * The same firmware loader is used as the GuC. Firmware * binary is fetched by
> + * the loader asynchronously from the driver init process. However, the actual
Remove * from "Firmware * binary". Loading is not asynchronous so remove this
statement.

> + * loading to HW is deferred until GEM initialization is done.
> + *
> + * Note that HuC firmware loading must be done before GuC loading.
> + */
> +
> +#define I915_SKL_HUC_UCODE "i915/skl_huc_ver01_07_1398.bin"
> +MODULE_FIRMWARE(I915_SKL_HUC_UCODE);
Please update to use the new approach used by GuC for specifying
required version and constructing the file path. See intel_guc_loader.c.
HuC firmware versioning includes the build number after the minor so
some modification will be needed.

> +
> +/**
> + * intel_huc_load_ucode() - DMA's the firmware
> + * @dev: the drm device
Fix name and parameter

> + *
> + * This function takes the gem object containing the firmware, sets up the DMA
> + * engine MMIO, triggers the DMA operation and waits for it to finish.
> + *
> + * Transfer the firmware image to RAM for execution by the microcontroller.
> + *
> + * Return: 0 on success, non-zero on failure
> + */
> +
> +static int huc_ucode_xfer(struct drm_i915_private *dev_priv)
> +{
> +	struct intel_uc_fw *huc_fw = &dev_priv->huc.huc_fw;
> +	struct i915_vma *vma;
> +	unsigned long offset = 0;
> +	u32 size;
> +	int ret;
> +
> +	ret = i915_gem_object_set_to_gtt_domain(huc_fw->uc_fw_obj, false);
> +	if (ret) {
> +		DRM_DEBUG_DRIVER("set-domain failed %d\n", ret);
> +		return ret;
> +	}
> +
> +	vma = i915_gem_object_ggtt_pin(huc_fw->uc_fw_obj, NULL, 0, 0, 0);
> +	if (IS_ERR(vma)) {
> +		DRM_DEBUG_DRIVER("pin failed %d\n", (int)PTR_ERR(vma));
> +		return PTR_ERR(vma);
> +	}
> +
> +	/* Invalidate GuC TLB to let GuC take the latest updates to GTT. */
> +	I915_WRITE(GEN8_GTCR, GEN8_GTCR_INVALIDATE);
> +
> +	WARN_ON(!mutex_is_locked(&dev_priv->drm.struct_mutex));
I don't see reason for this WARN_ON check. This function is called
in well defined paths that require locking way up the chain.
I think we can remove it.

> +	intel_uncore_forcewake_get(dev_priv, FORCEWAKE_ALL);
> +
> +	/* init WOPCM */
> +	I915_WRITE(GUC_WOPCM_SIZE, guc_wopcm_size(dev_priv));
> +	I915_WRITE(DMA_GUC_WOPCM_OFFSET, GUC_WOPCM_OFFSET_VALUE |
> +			HUC_LOADING_AGENT_GUC);
> +
> +	/* Set the source address for the uCode */
> +	offset = i915_ggtt_offset(vma) + huc_fw->header_offset;
> +	I915_WRITE(DMA_ADDR_0_LOW, lower_32_bits(offset));
> +	I915_WRITE(DMA_ADDR_0_HIGH, upper_32_bits(offset) & 0xFFFF);
> +
> +	/* Hardware doesn't look at destination address for HuC. Set it to 0,
> +	 * but still program the correct address space.
> +	 */
> +	I915_WRITE(DMA_ADDR_1_LOW, 0);
> +	I915_WRITE(DMA_ADDR_1_HIGH, DMA_ADDRESS_SPACE_WOPCM);
> +
> +	size = huc_fw->header_size + huc_fw->ucode_size;
> +	I915_WRITE(DMA_COPY_SIZE, size);
> +
> +	/* Start the DMA */
> +	I915_WRITE(DMA_CTRL, _MASKED_BIT_ENABLE(HUC_UKERNEL | START_DMA));
> +
> +	/* Wait for DMA to finish */
> +	ret = wait_for((I915_READ(DMA_CTRL) & START_DMA) == 0, 100);
> +
> +	DRM_DEBUG_DRIVER("HuC DMA transfer wait over with ret %d\n", ret);
> +
> +	intel_uncore_forcewake_put(dev_priv, FORCEWAKE_ALL);
> +
> +	/*
> +	 * We keep the object pages for reuse during resume. But we can unpin it
> +	 * now that DMA has completed, so it doesn't continue to take up space.
> +	 */
> +	i915_vma_unpin(vma);
> +
> +	return ret;
> +}
> +
> +/**
> + * intel_huc_init() - initiate HuC firmware loading request
> + * @dev: the drm device
> + *
> + * Called early during driver load, but after GEM is initialised. The loading
> + * will continue only when driver explicitly specify firmware name and version.
> + * All other cases are considered as UC_FIRMWARE_NONE either because HW is not
> + * capable or driver yet support it. And there will be no error message for
> + * UC_FIRMWARE_NONE cases.
> + *
> + * The DMA-copying to HW is done later when intel_huc_ucode_load() is called.
intel_huc_ucode_load() should be intel_huc_load().

> + */
> +void intel_huc_init(struct drm_device *dev)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(dev);
> +	struct intel_huc *huc = &dev_priv->huc;
> +	struct intel_uc_fw *huc_fw = &huc->huc_fw;
> +	const char *fw_path = NULL;
> +
> +	huc_fw->uc_dev = dev;
> +	huc_fw->uc_fw_path = NULL;
> +	huc_fw->fetch_status = UC_FIRMWARE_NONE;
> +	huc_fw->load_status = UC_FIRMWARE_NONE;
> +	huc_fw->fw_type = UC_FW_TYPE_HUC;
> +
> +	if (!HAS_HUC_UCODE(dev_priv))
> +		return;
> +
> +	if (IS_SKYLAKE(dev_priv)) {
> +		fw_path = I915_SKL_HUC_UCODE;
> +		huc_fw->major_ver_wanted = 1;
> +		huc_fw->minor_ver_wanted = 7;
> +	}
> +
> +	if (fw_path == NULL)
> +		return;
> +
> +	huc_fw->uc_fw_path = fw_path;
> +	huc_fw->fetch_status = UC_FIRMWARE_PENDING;
> +
> +	DRM_DEBUG_DRIVER("HuC firmware pending, path %s\n", fw_path);
> +
> +	intel_uc_fw_fetch(dev, huc_fw);
> +}
> +
> +/**
> + * intel_huc_load() - load HuC uCode to device
> + * @dev: the drm device
> + *
> + * Called from gem_init_hw() during driver loading and also after a GPU reset.
> + * Be note that HuC loading must be done before GuC loading.
> + *
> + * The firmware image should have already been fetched into memory by the
> + * earlier call to intel_huc_ucode_init(), so here we need only check that
> + * is succeeded, and then transfer the image to the h/w.
> + *
> + * Return:	non-zero code on error
> + */
> +int intel_huc_load(struct drm_device *dev)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(dev);
> +	struct intel_uc_fw *huc_fw = &dev_priv->huc.huc_fw;
> +	int err;
> +
> +	if (huc_fw->fetch_status == UC_FIRMWARE_NONE)
> +		return 0;
> +
> +	DRM_DEBUG_DRIVER("%s fw status: fetch %s, load %s\n",
> +		huc_fw->uc_fw_path,
> +		intel_uc_fw_status_repr(huc_fw->fetch_status),
> +		intel_uc_fw_status_repr(huc_fw->load_status));
> +
> +	if (huc_fw->fetch_status == UC_FIRMWARE_SUCCESS &&
> +	    huc_fw->load_status == UC_FIRMWARE_FAIL)
> +		return -ENOEXEC;
> +
> +	huc_fw->load_status = UC_FIRMWARE_PENDING;
> +
> +	switch (huc_fw->fetch_status) {
> +	case UC_FIRMWARE_FAIL:
> +		/* something went wrong :( */
> +		err = -EIO;
> +		goto fail;
> +
> +	case UC_FIRMWARE_NONE:
> +	case UC_FIRMWARE_PENDING:
> +	default:
> +		/* "can't happen" */
> +		WARN_ONCE(1, "HuC fw %s invalid fetch_status %s [%d]\n",
> +			huc_fw->uc_fw_path,
> +			intel_uc_fw_status_repr(huc_fw->fetch_status),
> +			huc_fw->fetch_status);
> +		err = -ENXIO;
> +		goto fail;
> +
> +	case UC_FIRMWARE_SUCCESS:
> +		break;
> +	}
> +
> +	err = huc_ucode_xfer(dev_priv);
> +	if (err)
> +		goto fail;
> +
> +	huc_fw->load_status = UC_FIRMWARE_SUCCESS;
> +
> +	DRM_DEBUG_DRIVER("%s fw status: fetch %s, load %s\n",
> +		huc_fw->uc_fw_path,
> +		intel_uc_fw_status_repr(huc_fw->fetch_status),
> +		intel_uc_fw_status_repr(huc_fw->load_status));
> +
> +	return 0;
> +
> +fail:
> +	if (huc_fw->load_status == UC_FIRMWARE_PENDING)
> +		huc_fw->load_status = UC_FIRMWARE_FAIL;
> +
> +	DRM_ERROR("Failed to complete HuC uCode load with ret %d\n", err);
> +
> +	return err;
> +}
> +
> +/**
> + * intel_huc_fini() - clean up resources allocated for HuC
> + * @dev: the drm device
> + *
> + * Cleans up by releasing the huc firmware GEM obj.
> + */
> +void intel_huc_fini(struct drm_device *dev)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(dev);
> +	struct intel_uc_fw *huc_fw = &dev_priv->huc.huc_fw;
> +
> +	mutex_lock(&dev->struct_mutex);
> +	if (huc_fw->uc_fw_obj)
> +		drm_gem_object_unreference(&huc_fw->uc_fw_obj->base);
These are now replaced with i915_gem_object_put(huc_fw->uc_fw_obj)

> +	huc_fw->uc_fw_obj = NULL;
> +	mutex_unlock(&dev->struct_mutex);
> +
> +	huc_fw->fetch_status = UC_FIRMWARE_NONE;
> +}
> -- 
> 2.7.4
> 
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