Re: [PATCH 2/6] drm/i915/huc: Unified css_header struct for GuC and HuC

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




-----Original Message-----
From: Gordon, David S 
Sent: Tuesday, June 28, 2016 3:33 PM
To: Antoine, Peter <peter.antoine@xxxxxxxxx>; intel-gfx@xxxxxxxxxxxxxxxxxxxxx
Cc: Prigent, Christophe <christophe.prigent@xxxxxxxxx>; Kelley, Sean V <sean.v.kelley@xxxxxxxxx>; Li, Lawrence T <lawrence.t.li@xxxxxxxxx>; Vivi, Rodrigo <rodrigo.vivi@xxxxxxxxx>; Dai, Yu <yu.dai@xxxxxxxxx>
Subject: Re: [PATCH 2/6] drm/i915/huc: Unified css_header struct for GuC and HuC

On 21/06/16 19:11, Peter Antoine wrote:
> From: Alex Dai <yu.dai@xxxxxxxxx>
>
> HuC firmware css header has almost exactly same definition as GuC 
> firmware except for the sw_version. Also, add a new member fw_type 
> into intel_uc_fw to indicate what kind of fw it is. So, the loader 
> will pull right sw_version from header.
>
> Signed-off-by: Alex Dai <yu.dai@xxxxxxxxx>
> Signed-off-by: Peter Antoine <peter.antoine@xxxxxxxxx>
> ---
>   drivers/gpu/drm/i915/intel_guc.h        |  4 ++++
>   drivers/gpu/drm/i915/intel_guc_fwif.h   | 16 ++++++++++---
>   drivers/gpu/drm/i915/intel_guc_loader.c | 42 +++++++++++++++++++++------------
>   3 files changed, 44 insertions(+), 18 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_guc.h 
> b/drivers/gpu/drm/i915/intel_guc.h
> index 836420b..0b4ed88 100644
> --- a/drivers/gpu/drm/i915/intel_guc.h
> +++ b/drivers/gpu/drm/i915/intel_guc.h
> @@ -97,6 +97,9 @@ enum intel_uc_fw_status {
>   	UC_FIRMWARE_SUCCESS
>   };
>
> +#define UC_FW_TYPE_GUC		0
> +#define UC_FW_TYPE_HUC		1
> +
>   /*
>    * This structure encapsulates all the data needed during the process
>    * of fetching, caching, and loading the firmware image into the GuC.
> @@ -114,6 +117,7 @@ struct intel_uc_fw {
>   	uint16_t major_ver_found;
>   	uint16_t minor_ver_found;
>
> +	uint32_t fw_type;
>   	uint32_t header_size;
>   	uint32_t header_offset;
>   	uint32_t rsa_size;
> diff --git a/drivers/gpu/drm/i915/intel_guc_fwif.h 
> b/drivers/gpu/drm/i915/intel_guc_fwif.h
> index 944786d..a69ee36 100644
> --- a/drivers/gpu/drm/i915/intel_guc_fwif.h
> +++ b/drivers/gpu/drm/i915/intel_guc_fwif.h
> @@ -154,7 +154,7 @@
>    * The GuC firmware layout looks like this:
>    *
>    *     +-------------------------------+
> - *     |        guc_css_header         |
> + *     |         uc_css_header         |
>    *     | contains major/minor version  |
>    *     +-------------------------------+
>    *     |             uCode             |
> @@ -180,9 +180,16 @@
>    * 3. Length info of each component can be found in header, in dwords.
>    * 4. Modulus and exponent key are not required by driver. They may not appear
>    * in fw. So driver will load a truncated firmware in this case.
> + *
> + * HuC firmware layout is same as GuC firmware.
> + *
> + * HuC firmware css header is different. However, the only difference 
> + is where
> + * the version information is saved. The uc_css_header is unified to 
> + support
> + * both. Driver should get HuC version from 
> + uc_css_header.huc_sw_version, while
> + * uc_css_header.guc_sw_version for GuC.
>    */
>
> -struct guc_css_header {
> +struct uc_css_header {

This name change could have been part of the previous global search-and-replace.

>   	uint32_t module_type;
>   	/* header_size includes all non-uCode bits, including css_header, rsa
>   	 * key, modulus key and exponent data. */ @@ -213,7 +220,10 @@ 
> struct guc_css_header {
>
>   	char username[8];
>   	char buildnumber[12];
> -	uint32_t device_id;
> +	union {
> +		uint32_t device_id;
> +		uint32_t huc_sw_version;
> +	};
>   	uint32_t guc_sw_version;
>   	uint32_t prod_preprod_fw;
>   	uint32_t reserved[12];

This can't really be right; the HuC f/w header doesn't contain a guc_sw_version! So the union must be more like:

	union {
		struct {
			uint32_t device_id;
			uint32_t guc_sw_version;
			uint32_t prod_preprod_fw;
		} guc_data;
		struct {
			uint32_t huc_sw_version;
			uint32_t prod_preprod_fw;
			uint32_t dummy;
		} huc_data;
	};
    	uint32_t reserved[12];

... or something - I don't know what the actual layout is here.

Otherwise generally OK.

.Dave.

Not really, It's not wrong. It just could be clearer. But adding other structs just muddies the water.
I think Alex's code is easier to read (and correct). Guc_sw_version is simply not used on the huc it is a bad design by the firmware designers not to use a fix format for all fw but just make the word we need a union is simplest.  

Probably could change it to:
Union {
	Struct {
  		Uint32_t device_id;
		Unit32_t guc_sw_version;
	};
	Struct {
		Uint32_t huc_sw_version;
		Uint32_t filler;
	};
} 
Just looking at the code. But I am going to leave it alone unless there is real objection to it.
Peter.

> diff --git a/drivers/gpu/drm/i915/intel_guc_loader.c 
> b/drivers/gpu/drm/i915/intel_guc_loader.c
> index ff054f5..70575bd 100644
> --- a/drivers/gpu/drm/i915/intel_guc_loader.c
> +++ b/drivers/gpu/drm/i915/intel_guc_loader.c
> @@ -574,7 +574,7 @@ void intel_uc_fw_fetch(struct drm_device *dev, struct intel_uc_fw *uc_fw)
>   {
>   	struct drm_i915_gem_object *obj;
>   	const struct firmware *fw;
> -	struct guc_css_header *css;
> +	struct uc_css_header *css;
>   	size_t size;
>   	int err;
>
> @@ -591,19 +591,19 @@ void intel_uc_fw_fetch(struct drm_device *dev, struct intel_uc_fw *uc_fw)
>   		uc_fw->uc_fw_path, fw);
>
>   	/* Check the size of the blob before examining buffer contents */
> -	if (fw->size < sizeof(struct guc_css_header)) {
> +	if (fw->size < sizeof(struct uc_css_header)) {
>   		DRM_ERROR("Firmware header is missing\n");
>   		goto fail;
>   	}
>
> -	css = (struct guc_css_header *)fw->data;
> +	css = (struct uc_css_header *)fw->data;
>
>   	/* Firmware bits always start from header */
>   	uc_fw->header_offset = 0;
>   	uc_fw->header_size = (css->header_size_dw - css->modulus_size_dw -
>   		css->key_size_dw - css->exponent_size_dw) * sizeof(u32);
>
> -	if (uc_fw->header_size != sizeof(struct guc_css_header)) {
> +	if (uc_fw->header_size != sizeof(struct uc_css_header)) {
>   		DRM_ERROR("CSS header definition mismatch\n");
>   		goto fail;
>   	}
> @@ -627,23 +627,35 @@ void intel_uc_fw_fetch(struct drm_device *dev, struct intel_uc_fw *uc_fw)
>   		goto fail;
>   	}
>
> -	/* Header and uCode will be loaded to WOPCM. Size of the two. */
> -	size = uc_fw->header_size + uc_fw->ucode_size;
> -
> -	/* Top 32k of WOPCM is reserved (8K stack + 24k RC6 context). */
> -	if (size > guc_wopcm_size(dev->dev_private)) {
> -		DRM_ERROR("Firmware is too large to fit in WOPCM\n");
> -		goto fail;
> -	}
> -
>   	/*
>   	 * The uC firmware image has the version number embedded at a well-known
>   	 * offset within the firmware blob; note that major / minor version are
>   	 * TWO bytes each (i.e. u16), although all pointers and offsets are defined
>   	 * in terms of bytes (u8).
>   	 */
> -	uc_fw->major_ver_found = css->guc_sw_version >> 16;
> -	uc_fw->minor_ver_found = css->guc_sw_version & 0xFFFF;
> +	switch (uc_fw->fw_type) {
> +	case UC_FW_TYPE_GUC:
> +		/* Header and uCode will be loaded to WOPCM. Size of the two. */
> +		size = uc_fw->header_size + uc_fw->ucode_size;
> +
> +		/* Top 32k of WOPCM is reserved (8K stack + 24k RC6 context). */
> +		if (size > guc_wopcm_size(dev->dev_private)) {
> +			DRM_ERROR("Firmware is too large to fit in WOPCM\n");
> +			goto fail;
> +		}
> +
> +		uc_fw->major_ver_found = css->guc_sw_version >> 16;
> +		uc_fw->minor_ver_found = css->guc_sw_version & 0xFFFF;
> +		break;
> +	case UC_FW_TYPE_HUC:
> +		uc_fw->major_ver_found = css->huc_sw_version >> 16;
> +		uc_fw->minor_ver_found = css->huc_sw_version & 0xFFFF;
> +		break;
> +	default:
> +		DRM_ERROR("Unknown firmware type %d\n", uc_fw->fw_type);
> +		err = -ENOEXEC;
> +		goto fail;
> +	}
>
>   	if (uc_fw->major_ver_found != uc_fw->major_ver_wanted ||
>   	    uc_fw->minor_ver_found < uc_fw->minor_ver_wanted) {
>

_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/intel-gfx




[Index of Archives]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]
  Powered by Linux