[Intel-xe] [PATCH v4 3/9] drm/xe/xe2: Updates on XY_CTRL_SURF_COPY_BLT

[Matt Roper]

On Wed, Dec 06, 2023 at 10:01:20AM +0530, Himal Prasad Ghimiray wrote:
> - The XY_CTRL_SURF_COPY_BLT instruction operationg on ccs data expects
> size in pages of main memory for which CCS data should be copied.
> - The bitfield representing copy size in XY_CTRL_SURF_COPY_BLT has
> shifted one bit higher in the instruction.
> 
> v2:
>  - Fix the num_pages for ccs size calculation.
>  - Address nits (Thomas)
> 
> Reviewed-by: Thomas Hellström <thomas.hellstrom at linux.intel.com>
> Cc: Thomas Hellström <thomas.hellstrom at linux.intel.com>
> Signed-off-by: Himal Prasad Ghimiray <himal.prasad.ghimiray at intel.com>
> ---
>  drivers/gpu/drm/xe/regs/xe_gpu_commands.h |  1 +
>  drivers/gpu/drm/xe/xe_migrate.c           | 21 +++++++++++++++------
>  2 files changed, 16 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/gpu/drm/xe/regs/xe_gpu_commands.h b/drivers/gpu/drm/xe/regs/xe_gpu_commands.h
> index 1f9c32e694c6..6ff6c7aaa648 100644
> --- a/drivers/gpu/drm/xe/regs/xe_gpu_commands.h
> +++ b/drivers/gpu/drm/xe/regs/xe_gpu_commands.h
> @@ -13,6 +13,7 @@
>  #define   DST_ACCESS_TYPE_SHIFT		20
>  #define   CCS_SIZE_MASK			0x3FF
>  #define   CCS_SIZE_SHIFT		8
> +#define   XE2_CCS_SIZE_SHIFT		9

It would be preferred if we just removed the shifts and used
FIELD_PREP() to put values into proper field masks instead.

>  #define   XY_CTRL_SURF_MOCS_MASK	GENMASK(31, 26)
>  #define   XE2_XY_CTRL_SURF_MOCS_INDEX_MASK	GENMASK(31, 28)
>  #define   NUM_CCS_BYTES_PER_BLOCK	256
> diff --git a/drivers/gpu/drm/xe/xe_migrate.c b/drivers/gpu/drm/xe/xe_migrate.c
> index e8b567708ac0..7ef068451b59 100644
> --- a/drivers/gpu/drm/xe/xe_migrate.c
> +++ b/drivers/gpu/drm/xe/xe_migrate.c
> @@ -526,21 +526,30 @@ static void emit_copy_ccs(struct xe_gt *gt, struct xe_bb *bb,
>  	struct xe_device *xe = gt_to_xe(gt);
>  	u32 *cs = bb->cs + bb->len;
>  	u32 num_ccs_blks;
> +	u32 num_pages;
> +	u32 ccs_copy_size;
>  	u32 mocs;
>  
> -	num_ccs_blks = DIV_ROUND_UP(xe_device_ccs_bytes(gt_to_xe(gt), size),
> -				    NUM_CCS_BYTES_PER_BLOCK);
> -	xe_gt_assert(gt, num_ccs_blks <= NUM_CCS_BLKS_PER_XFER);
> +	if (GRAPHICS_VERx100(xe) >= 2000) {
> +		num_pages = DIV_ROUND_UP(size, XE_PAGE_SIZE);
> +		xe_gt_assert(gt, num_pages <= 1024);

Rather than using a magic number here, FIELD_FIT() might be better.  We
can do the same for the other branch as well and get rid of
NUM_CCS_BLKS_PER_XFER too.


Matt

>  
> -	if (GRAPHICS_VERx100(xe) >= 2000)
> +		ccs_copy_size = ((num_pages - 1) & CCS_SIZE_MASK) << XE2_CCS_SIZE_SHIFT;
>  		mocs = FIELD_PREP(XE2_XY_CTRL_SURF_MOCS_INDEX_MASK, gt->mocs.uc_index);
> -	else
> +
> +	} else {
> +		num_ccs_blks = DIV_ROUND_UP(xe_device_ccs_bytes(gt_to_xe(gt), size),
> +					    NUM_CCS_BYTES_PER_BLOCK);
> +		xe_gt_assert(gt, num_ccs_blks <= NUM_CCS_BLKS_PER_XFER);
> +
> +		ccs_copy_size = ((num_ccs_blks - 1) & CCS_SIZE_MASK) << CCS_SIZE_SHIFT;
>  		mocs = FIELD_PREP(XY_CTRL_SURF_MOCS_MASK, gt->mocs.uc_index);
> +	}
>  
>  	*cs++ = XY_CTRL_SURF_COPY_BLT |
>  		(src_is_indirect ? 0x0 : 0x1) << SRC_ACCESS_TYPE_SHIFT |
>  		(dst_is_indirect ? 0x0 : 0x1) << DST_ACCESS_TYPE_SHIFT |
> -		((num_ccs_blks - 1) & CCS_SIZE_MASK) << CCS_SIZE_SHIFT;
> +		ccs_copy_size;
>  	*cs++ = lower_32_bits(src_ofs);
>  	*cs++ = upper_32_bits(src_ofs) | mocs;
>  	*cs++ = lower_32_bits(dst_ofs);
> -- 
> 2.25.1
> 

-- 
Matt Roper
Graphics Software Engineer
Linux GPU Platform Enablement
Intel Corporation