Enabling atomic operations in L3 leads to unrecoverable GPU hangs, as the machine stops responding milliseconds after receipt of the reset request [GDRT]. By disabling the cached atomics, the hang do not occur and we presume the GPU would reset normally for similar hangs.
Reported-by: Jason Ekstrand <[email protected]> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=110998 Signed-off-by: Chris Wilson <[email protected]> Cc: Jason Ekstrand <[email protected]> Cc: Mika Kuoppala <[email protected]> Cc: Tvrtko Ursulin <[email protected]> Reviewed-by: Jason Ekstrand <[email protected]> --- drivers/gpu/drm/i915/gt/intel_workarounds.c | 8 ++++++++ drivers/gpu/drm/i915/i915_reg.h | 7 +++++++ 2 files changed, 15 insertions(+) diff --git a/drivers/gpu/drm/i915/gt/intel_workarounds.c b/drivers/gpu/drm/i915/gt/intel_workarounds.c index 82e15c8c7a97..7a1d8c68aefb 100644 --- a/drivers/gpu/drm/i915/gt/intel_workarounds.c +++ b/drivers/gpu/drm/i915/gt/intel_workarounds.c @@ -1840,6 +1840,14 @@ rcs_engine_wa_init(struct intel_engine_cs *engine, struct i915_wa_list *wal) wa_write_or(wal, GEN8_L3SQCREG4, GEN8_LQSC_FLUSH_COHERENT_LINES); + + /* Disable atomics in L3 to prevent unrecoverable hangs */ + wa_write_masked_or(wal, GEN9_SCRATCH_LNCF1, + GEN9_LNCF_NONIA_COHERENT_ATOMICS_ENABLE, 0); + wa_write_masked_or(wal, GEN8_L3SQCREG4, + GEN8_LQSQ_NONIA_COHERENT_ATOMICS_ENABLE, 0); + wa_write_masked_or(wal, GEN9_SCRATCH1, + EVICTION_PERF_FIX_ENABLE, 0); } if (IS_HASWELL(i915)) { diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index 8b9bbc6bacb1..fa3866f9ccfc 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -8222,6 +8222,7 @@ enum { #define GEN11_LQSC_CLEAN_EVICT_DISABLE (1 << 6) #define GEN8_LQSC_RO_PERF_DIS (1 << 27) #define GEN8_LQSC_FLUSH_COHERENT_LINES (1 << 21) +#define GEN8_LQSQ_NONIA_COHERENT_ATOMICS_ENABLE REG_BIT(22) /* GEN8 chicken */ #define HDC_CHICKEN0 _MMIO(0x7300) @@ -12104,6 +12105,12 @@ enum skl_power_gate { #define __GEN11_VCS2_MOCS0 0x10000 #define GEN11_MFX2_MOCS(i) _MMIO(__GEN11_VCS2_MOCS0 + (i) * 4) +#define GEN9_SCRATCH_LNCF1 _MMIO(0xb008) +#define GEN9_LNCF_NONIA_COHERENT_ATOMICS_ENABLE REG_BIT(0) + +#define GEN9_SCRATCH1 _MMIO(0xb11c) +#define EVICTION_PERF_FIX_ENABLE REG_BIT(8) + #define GEN10_SCRATCH_LNCF2 _MMIO(0xb0a0) #define PMFLUSHDONE_LNICRSDROP (1 << 20) #define PMFLUSH_GAPL3UNBLOCK (1 << 21) -- 2.20.1 _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
