xref: /linux/drivers/gpu/drm/i915/gt/intel_gt_ccs_mode.c (revision 20dfee95936413708701eb151f419597fdd9d948)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2024 Intel Corporation
4  */
5 
6 #include "i915_drv.h"
7 #include "intel_gt.h"
8 #include "intel_gt_ccs_mode.h"
9 #include "intel_gt_regs.h"
10 
11 unsigned int intel_gt_apply_ccs_mode(struct intel_gt *gt)
12 {
13 	int cslice;
14 	u32 mode = 0;
15 	int first_ccs = __ffs(CCS_MASK(gt));
16 
17 	if (!IS_DG2(gt->i915))
18 		return 0;
19 
20 	/* Build the value for the fixed CCS load balancing */
21 	for (cslice = 0; cslice < I915_MAX_CCS; cslice++) {
22 		if (gt->ccs.cslices & BIT(cslice))
23 			/*
24 			 * If available, assign the cslice
25 			 * to the first available engine...
26 			 */
27 			mode |= XEHP_CCS_MODE_CSLICE(cslice, first_ccs);
28 
29 		else
30 			/*
31 			 * ... otherwise, mark the cslice as
32 			 * unavailable if no CCS dispatches here
33 			 */
34 			mode |= XEHP_CCS_MODE_CSLICE(cslice,
35 						     XEHP_CCS_MODE_CSLICE_MASK);
36 	}
37 
38 	return mode;
39 }
40