diff options
Diffstat (limited to 'drivers/gpu/drm/i915/intel_uncore.c')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_uncore.c | 47 |
1 files changed, 44 insertions, 3 deletions
diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c index e1e1f34490c8..796ebfe6c550 100644 --- a/drivers/gpu/drm/i915/intel_uncore.c +++ b/drivers/gpu/drm/i915/intel_uncore.c @@ -177,12 +177,19 @@ wait_ack_set(const struct intel_uncore_forcewake_domain *d, static inline void fw_domain_wait_ack_clear(const struct intel_uncore_forcewake_domain *d) { - if (wait_ack_clear(d, FORCEWAKE_KERNEL)) { + if (!wait_ack_clear(d, FORCEWAKE_KERNEL)) + return; + + if (fw_ack(d) == ~0) + drm_err(&d->uncore->i915->drm, + "%s: MMIO unreliable (forcewake register returns 0xFFFFFFFF)!\n", + intel_uncore_forcewake_domain_to_str(d->id)); + else drm_err(&d->uncore->i915->drm, "%s: timed out waiting for forcewake ack to clear.\n", intel_uncore_forcewake_domain_to_str(d->id)); - add_taint_for_CI(d->uncore->i915, TAINT_WARN); /* CI now unreliable */ - } + + add_taint_for_CI(d->uncore->i915, TAINT_WARN); /* CI now unreliable */ } enum ack_type { @@ -2602,11 +2609,45 @@ static int uncore_forcewake_init(struct intel_uncore *uncore) return 0; } +static int sanity_check_mmio_access(struct intel_uncore *uncore) +{ + struct drm_i915_private *i915 = uncore->i915; + + if (GRAPHICS_VER(i915) < 8) + return 0; + + /* + * Sanitycheck that MMIO access to the device is working properly. If + * the CPU is unable to communcate with a PCI device, BAR reads will + * return 0xFFFFFFFF. Let's make sure the device isn't in this state + * before we start trying to access registers. + * + * We use the primary GT's forcewake register as our guinea pig since + * it's been around since HSW and it's a masked register so the upper + * 16 bits can never read back as 1's if device access is operating + * properly. + * + * If MMIO isn't working, we'll wait up to 2 seconds to see if it + * recovers, then give up. + */ +#define COND (__raw_uncore_read32(uncore, FORCEWAKE_MT) != ~0) + if (wait_for(COND, 2000) == -ETIMEDOUT) { + drm_err(&i915->drm, "Device is non-operational; MMIO access returns 0xFFFFFFFF!\n"); + return -EIO; + } + + return 0; +} + int intel_uncore_init_mmio(struct intel_uncore *uncore) { struct drm_i915_private *i915 = uncore->i915; int ret; + ret = sanity_check_mmio_access(uncore); + if (ret) + return ret; + /* * The boot firmware initializes local memory and assesses its health. * If memory training fails, the punit will have been instructed to |