Commit 764af38a authored by Matt Roper's avatar Matt Roper
Browse files

drm/xe/reg_sr: Allow register_save_restore_check debugfs to verify LRC values 



reg_sr programming that applies to an engines LRC cannot be verified by
a simple CPU-based register readout because the reg_sr's values may not
be in effect if no context is executing on the hardware at the time we
check.  Instead, we should verify correct reg_sr application by
searching for the register in the default_lrc.

Reviewed-by: default avatarAshutosh Dixit <ashutosh.dixit@intel.com>
Link: https://patch.msgid.link/20260218-sr_verify-v4-4-35d6deeb3421@intel.com


Signed-off-by: default avatarMatt Roper <matthew.d.roper@intel.com>
parent e950b060

drivers/gpu/drm/xe/xe_gt_debugfs.c

+2 −2
Original line number Diff line number Diff line
@@ -173,8 +173,8 @@ static int register_save_restore_check(struct xe_gt *gt, struct drm_printer *p) 
	xe_reg_sr_readback_check(&gt->reg_sr, gt, p);

	for_each_hw_engine(hwe, gt, id)

		xe_reg_sr_readback_check(&hwe->reg_sr, gt, p);



	/* TODO: Check hwe->reg_lrc against contents of default_lrc. */

	for_each_hw_engine(hwe, gt, id)

		xe_reg_sr_lrc_check(&hwe->reg_lrc, gt, hwe, p);



	return 0;

}

drivers/gpu/drm/xe/xe_reg_sr.c

+30 −0
Original line number Diff line number Diff line
@@ -21,6 +21,7 @@ 
#include "xe_gt_printk.h"

#include "xe_gt_types.h"

#include "xe_hw_engine_types.h"

#include "xe_lrc.h"

#include "xe_mmio.h"

#include "xe_rtp_types.h"
@@ -242,3 +243,32 @@ void xe_reg_sr_readback_check(struct xe_reg_sr *sr, 
				   offset, mask, entry->set_bits, val & mask);

	}

}



/**

 * xe_reg_sr_lrc_check() - Check LRC for registers referenced in save/restore

 *     entries and check whether the programming is in place.

 * @sr: Save/restore entries

 * @gt: GT to read register from

 * @hwe: Hardware engine type to check LRC for

 * @p: DRM printer to report discrepancies on

 */

void xe_reg_sr_lrc_check(struct xe_reg_sr *sr,

			 struct xe_gt *gt,

			 struct xe_hw_engine *hwe,

			 struct drm_printer *p)

{

	struct xe_reg_sr_entry *entry;

	unsigned long offset;



	xa_for_each(&sr->xa, offset, entry) {

		u32 val;

		int ret = xe_lrc_lookup_default_reg_value(gt, hwe->class, offset, &val);

		u32 mask = entry->clr_bits | entry->set_bits;



		if (ret == -ENOENT)

			drm_printf(p, "%#8lx :: not found in LRC for %s\n", offset, hwe->name);

		else if ((val & mask) != entry->set_bits)

			drm_printf(p, "%#8lx & %#10x :: expected %#10x got %#10x\n",

				   offset, mask, entry->set_bits, val & mask);

	}

}

drivers/gpu/drm/xe/xe_reg_sr.h

+4 −0
Original line number Diff line number Diff line
@@ -22,6 +22,10 @@ void xe_reg_sr_dump(struct xe_reg_sr *sr, struct drm_printer *p); 
void xe_reg_sr_readback_check(struct xe_reg_sr *sr,

			      struct xe_gt *gt,

			      struct drm_printer *p);

void xe_reg_sr_lrc_check(struct xe_reg_sr *sr,

			 struct xe_gt *gt,

			 struct xe_hw_engine *hwe,

			 struct drm_printer *p);



int xe_reg_sr_add(struct xe_reg_sr *sr, const struct xe_reg_sr_entry *e,

		  struct xe_gt *gt);