From: Imre Deak <imre.deak@intel.com>
Date: Thu, 8 Feb 2018 13:23:31 +0200
Subject: drm/i915/snb+: Remove incorrect forcewake check in
debugfs/i915_drpc_info
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Git-commit: 928f0cd0eb0511e19b416e34a030ebff6785fa52
Patch-mainline: v4.17-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166
FORCEWAKE_ACK is depricated by BSpec at least starting from BDW,
referring to the multi-threaded version of it instead. Accessing
FORCEWAKE_ACK triggers an unclaimed register access error - at
least on GLK - see the Reference: below.
The correct registers to use would be FORCEWAKE_MT_ACK on IVB+ and
FORCEWAKE_ACK_RENDER_GEN9 on SKL+ like it's done elsewhere in the
driver.
The forcewake check itself is inconsistent and redundant, since there
could be other forcewake requesters besides the kernel (being the
multithreaded version of the register) and the kernel's per-domain
forcewake counters are shown anyway at the end of the file. So let's
just remove the check.
Suggested-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reference: https://bugs.freedesktop.org/show_bug.cgi?id=103337
Signed-off-by: Imre Deak <imre.deak@intel.com>
Tested-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20180208112331.12986-1-imre.deak@intel.com
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
drivers/gpu/drm/i915/i915_debugfs.c | 13 -------------
1 file changed, 13 deletions(-)
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -1460,19 +1460,6 @@ static int gen6_drpc_info(struct seq_fil
struct drm_i915_private *dev_priv = node_to_i915(m->private);
u32 gt_core_status, rcctl1, rc6vids = 0;
u32 gen9_powergate_enable = 0, gen9_powergate_status = 0;
- unsigned forcewake_count;
- int count = 0;
-
- forcewake_count = READ_ONCE(dev_priv->uncore.fw_domain[FW_DOMAIN_ID_RENDER].wake_count);
- if (forcewake_count) {
- seq_puts(m, "RC information inaccurate because somebody "
- "holds a forcewake reference \n");
- } else {
- /* NB: we cannot use forcewake, else we read the wrong values */
- while (count++ < 50 && (I915_READ_NOTRACE(FORCEWAKE_ACK) & 1))
- udelay(10);
- seq_printf(m, "RC information accurate: %s\n", yesno(count < 51));
- }
gt_core_status = I915_READ_FW(GEN6_GT_CORE_STATUS);
trace_i915_reg_rw(false, GEN6_GT_CORE_STATUS, gt_core_status, 4, true);