On 31-10-2022 23:16, Matt Roper wrote:
> On Mon, Oct 31, 2022 at 06:01:11PM +0530, Aravind Iddamsetty wrote:
>> On XE_LPM+ platforms the media engines are carved out into a separate
>> GT but have a common GGTMMADR address range which essentially makes
>> the GGTT address space to be shared between media and render GT.
>
> While this is all true, I feel like this description is lacking a bit of
> explanation for why/how that translates into the code changes below.
> For example you should elaborate on the areas this impacts, such as the
> need to invalidate both GTs' TLBs, retire requests for both GTs, etc.
>
> Also, the movement of the PAT setup should be noted and explained as
> well since it differs from how you approached the other changes here.
>
>>
>> BSPEC: 63834
>>
>> Cc: Matt Roper <matthew.d.roper@xxxxxxxxx>
>> Signed-off-by: Aravind Iddamsetty <aravind.iddamsetty@xxxxxxxxx>
>> ---
>> drivers/gpu/drm/i915/gt/intel_ggtt.c | 49 +++++++++++-------
>> drivers/gpu/drm/i915/gt/intel_gt.c | 15 +++++-
>> drivers/gpu/drm/i915/gt/intel_gt_types.h | 3 ++
>> drivers/gpu/drm/i915/gt/intel_gtt.h | 3 ++
>> drivers/gpu/drm/i915/i915_driver.c | 19 +++++--
>> drivers/gpu/drm/i915/i915_gem_evict.c | 63 +++++++++++++++++------
>> drivers/gpu/drm/i915/i915_vma.c | 5 +-
>> drivers/gpu/drm/i915/selftests/i915_gem.c | 2 +
>> drivers/gpu/drm/i915/selftests/mock_gtt.c | 1 +
>> 9 files changed, 115 insertions(+), 45 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/gt/intel_ggtt.c b/drivers/gpu/drm/i915/gt/intel_ggtt.c
>> index 2518cebbf931..f5c2f3c58627 100644
>> --- a/drivers/gpu/drm/i915/gt/intel_ggtt.c
>> +++ b/drivers/gpu/drm/i915/gt/intel_ggtt.c
>> @@ -196,10 +196,13 @@ void i915_ggtt_suspend_vm(struct i915_address_space *vm)
>>
>> void i915_ggtt_suspend(struct i915_ggtt *ggtt)
>> {
>> + struct intel_gt *gt;
>> +
>> i915_ggtt_suspend_vm(&ggtt->vm);
>> ggtt->invalidate(ggtt);
>>
>> - intel_gt_check_and_clear_faults(ggtt->vm.gt);
>> + list_for_each_entry(gt, &ggtt->gt_list, ggtt_link)
>> + intel_gt_check_and_clear_faults(gt);
>> }
>>
>> void gen6_ggtt_invalidate(struct i915_ggtt *ggtt)
>> @@ -214,27 +217,36 @@ void gen6_ggtt_invalidate(struct i915_ggtt *ggtt)
>>
>> static void gen8_ggtt_invalidate(struct i915_ggtt *ggtt)
>> {
>> - struct intel_uncore *uncore = ggtt->vm.gt->uncore;
>> + struct intel_uncore *uncore;
>> + struct intel_gt *gt;
>>
>> - /*
>> - * Note that as an uncached mmio write, this will flush the
>> - * WCB of the writes into the GGTT before it triggers the invalidate.
>> - */
>> - intel_uncore_write_fw(uncore, GFX_FLSH_CNTL_GEN6, GFX_FLSH_CNTL_EN);
>> + list_for_each_entry(gt, &ggtt->gt_list, ggtt_link) {
>> + uncore = gt->uncore;
>> + /*
>> + * Note that as an uncached mmio write, this will flush the
>> + * WCB of the writes into the GGTT before it triggers the invalidate.
>> + */
>> + intel_uncore_write_fw(uncore, GFX_FLSH_CNTL_GEN6, GFX_FLSH_CNTL_EN);
>
> This isn't a GT register, so writing it for each GT doesn't do anything
> different than just writing it once. But actually it doesn't look like
> this is even a register we should be writing to anymore since Xe_HP.
> The GFX_FLSH_CNTL register no longer lives here.
Ok I'll remove the iteration over gt, also i do not see an equivalent
register for Xe_HP, so i'll leave this as it is for now.
>
>> + }
>> }
>>
>> static void guc_ggtt_invalidate(struct i915_ggtt *ggtt)
>> {
>> - struct intel_uncore *uncore = ggtt->vm.gt->uncore;
>> struct drm_i915_private *i915 = ggtt->vm.i915;
>>
>> gen8_ggtt_invalidate(ggtt);
>>
>> - if (GRAPHICS_VER(i915) >= 12)
>> - intel_uncore_write_fw(uncore, GEN12_GUC_TLB_INV_CR,
>> - GEN12_GUC_TLB_INV_CR_INVALIDATE);
>> - else
>> - intel_uncore_write_fw(uncore, GEN8_GTCR, GEN8_GTCR_INVALIDATE);
>> + if (GRAPHICS_VER(i915) >= 12) {
>> + struct intel_gt *gt;
>> +
>> + list_for_each_entry(gt, &ggtt->gt_list, ggtt_link)
>> + intel_uncore_write_fw(gt->uncore,
>> + GEN12_GUC_TLB_INV_CR,
>> + GEN12_GUC_TLB_INV_CR_INVALIDATE);
>> + } else {
>> + intel_uncore_write_fw(ggtt->vm.gt->uncore,
>> + GEN8_GTCR, GEN8_GTCR_INVALIDATE);
>> + }
>> }
>>
>> u64 gen8_ggtt_pte_encode(dma_addr_t addr,
>> @@ -986,8 +998,6 @@ static int gen8_gmch_probe(struct i915_ggtt *ggtt)
>>
>> ggtt->vm.pte_encode = gen8_ggtt_pte_encode;
>>
>> - setup_private_pat(ggtt->vm.gt);
>> -
>> return ggtt_probe_common(ggtt, size);
>> }
>>
>> @@ -1186,7 +1196,7 @@ static int ggtt_probe_hw(struct i915_ggtt *ggtt, struct intel_gt *gt)
>> (u64)ggtt->mappable_end >> 20);
>> drm_dbg(&i915->drm, "DSM size = %lluM\n",
>> (u64)resource_size(&intel_graphics_stolen_res) >> 20);
>> -
>> + INIT_LIST_HEAD(&ggtt->gt_list);
>> return 0;
>> }
>>
>> @@ -1296,9 +1306,11 @@ bool i915_ggtt_resume_vm(struct i915_address_space *vm)
>>
>> void i915_ggtt_resume(struct i915_ggtt *ggtt)
>> {
>> + struct intel_gt *gt;
>> bool flush;
>>
>> - intel_gt_check_and_clear_faults(ggtt->vm.gt);
>> + list_for_each_entry(gt, &ggtt->gt_list, ggtt_link)
>> + intel_gt_check_and_clear_faults(gt);
>>
>> flush = i915_ggtt_resume_vm(&ggtt->vm);
>>
>> @@ -1307,9 +1319,6 @@ void i915_ggtt_resume(struct i915_ggtt *ggtt)
>> if (flush)
>> wbinvd_on_all_cpus();
>>
>> - if (GRAPHICS_VER(ggtt->vm.i915) >= 8)
>> - setup_private_pat(ggtt->vm.gt);
>> -
>> intel_ggtt_restore_fences(ggtt);
>> }
>>
>> diff --git a/drivers/gpu/drm/i915/gt/intel_gt.c b/drivers/gpu/drm/i915/gt/intel_gt.c
>> index 2e796ffad911..d72efb74563a 100644
>> --- a/drivers/gpu/drm/i915/gt/intel_gt.c
>> +++ b/drivers/gpu/drm/i915/gt/intel_gt.c
>> @@ -110,9 +110,17 @@ static int intel_gt_probe_lmem(struct intel_gt *gt)
>>
>> int intel_gt_assign_ggtt(struct intel_gt *gt)
>> {
>> - gt->ggtt = drmm_kzalloc(>->i915->drm, sizeof(*gt->ggtt), GFP_KERNEL);
>> + /* Media GT shares primary GT's GGTT */
>> + if (gt->type == GT_MEDIA) {
>> + gt->ggtt = to_gt(gt->i915)->ggtt;
>> + } else {
>> + gt->ggtt = drmm_kzalloc(>->i915->drm, sizeof(*gt->ggtt), GFP_KERNEL);
>> + if (!gt->ggtt)
>> + return -ENOMEM;
>> + }
>>
>> - return gt->ggtt ? 0 : -ENOMEM;
>> + list_add_tail(>->ggtt_link, >->ggtt->gt_list);
>> + return 0;
>> }
>>
>> int intel_gt_init_mmio(struct intel_gt *gt)
>> @@ -965,6 +973,9 @@ int intel_gt_tiles_init(struct drm_i915_private *i915)
>> int ret;
>>
>> for_each_gt(gt, i915, id) {
>> + if (GRAPHICS_VER(i915) >= 8)
>> + setup_private_pat(gt);
>> +
>
> Since the term "tile" is used for PVC-style remote tiles (which we have
> some framework for, but haven't enabled yet), it seems confusing to have
> the PAT setup for all GTs (including the standalone media GT) in a
> function called intel_gt_tiles_init(). Maybe we should also have a prep
> patch that renames this function if we're going to start doing non-tile
> things in here too?
i'll move this to i915_driver_hw_probe
>
>> ret = intel_gt_probe_lmem(gt);
>> if (ret)
>> return ret;
>> diff --git a/drivers/gpu/drm/i915/gt/intel_gt_types.h b/drivers/gpu/drm/i915/gt/intel_gt_types.h
>> index 6f686a4244f0..aee37e9e79b0 100644
>> --- a/drivers/gpu/drm/i915/gt/intel_gt_types.h
>> +++ b/drivers/gpu/drm/i915/gt/intel_gt_types.h
>> @@ -292,6 +292,9 @@ struct intel_gt {
>> struct kobject *sysfs_defaults;
>>
>> struct i915_perf_gt perf;
>> +
>> + /** link: &ggtt.gt_list */
>> + struct list_head ggtt_link;
>> };
>>
>> struct intel_gt_definition {
>> diff --git a/drivers/gpu/drm/i915/gt/intel_gtt.h b/drivers/gpu/drm/i915/gt/intel_gtt.h
>> index 4d75ba4bb41d..cb1272702a1a 100644
>> --- a/drivers/gpu/drm/i915/gt/intel_gtt.h
>> +++ b/drivers/gpu/drm/i915/gt/intel_gtt.h
>> @@ -390,6 +390,9 @@ struct i915_ggtt {
>> struct mutex error_mutex;
>> struct drm_mm_node error_capture;
>> struct drm_mm_node uc_fw;
>> +
>> + /** List of GTs mapping this GGTT */
>> + struct list_head gt_list;
>> };
>>
>> struct i915_ppgtt {
>> diff --git a/drivers/gpu/drm/i915/i915_driver.c b/drivers/gpu/drm/i915/i915_driver.c
>> index c3d43f9b1e45..6b973182ddcc 100644
>> --- a/drivers/gpu/drm/i915/i915_driver.c
>> +++ b/drivers/gpu/drm/i915/i915_driver.c
>> @@ -577,7 +577,8 @@ static int i915_driver_hw_probe(struct drm_i915_private *dev_priv)
>> {
>> struct pci_dev *pdev = to_pci_dev(dev_priv->drm.dev);
>> struct pci_dev *root_pdev;
>> - int ret;
>> + struct intel_gt *gt;
>> + int ret, i;
>>
>> if (i915_inject_probe_failure(dev_priv))
>> return -ENODEV;
>> @@ -614,9 +615,11 @@ static int i915_driver_hw_probe(struct drm_i915_private *dev_priv)
>>
>> i915_perf_init(dev_priv);
>>
>> - ret = intel_gt_assign_ggtt(to_gt(dev_priv));
>> - if (ret)
>> - goto err_perf;
>> + for_each_gt(gt, dev_priv, i) {
>> + ret = intel_gt_assign_ggtt(gt);
>> + if (ret)
>> + goto err_perf;
>> + }
>>
>> ret = i915_ggtt_probe_hw(dev_priv);
>> if (ret)
>> @@ -1318,7 +1321,8 @@ int i915_driver_suspend_switcheroo(struct drm_i915_private *i915,
>> static int i915_drm_resume(struct drm_device *dev)
>> {
>> struct drm_i915_private *dev_priv = to_i915(dev);
>> - int ret;
>> + struct intel_gt *gt;
>> + int ret, i;
>>
>> disable_rpm_wakeref_asserts(&dev_priv->runtime_pm);
>>
>> @@ -1333,6 +1337,11 @@ static int i915_drm_resume(struct drm_device *dev)
>> drm_err(&dev_priv->drm, "failed to re-enable GGTT\n");
>>
>> i915_ggtt_resume(to_gt(dev_priv)->ggtt);
>> +
>> + for_each_gt(gt, dev_priv, i)
>> + if (GRAPHICS_VER(gt->i915) >= 8)
>> + setup_private_pat(gt);
>> +
>> /* Must be called after GGTT is resumed. */
>> intel_dpt_resume(dev_priv);
>>
>> diff --git a/drivers/gpu/drm/i915/i915_gem_evict.c b/drivers/gpu/drm/i915/i915_gem_evict.c
>> index f025ee4fa526..e9d4352ebfb8 100644
>> --- a/drivers/gpu/drm/i915/i915_gem_evict.c
>> +++ b/drivers/gpu/drm/i915/i915_gem_evict.c
>> @@ -43,16 +43,30 @@ static bool dying_vma(struct i915_vma *vma)
>> return !kref_read(&vma->obj->base.refcount);
>> }
>>
>> -static int ggtt_flush(struct intel_gt *gt)
>> +static int ggtt_flush(struct i915_address_space *vm)
>> {
>> - /*
>> - * Not everything in the GGTT is tracked via vma (otherwise we
>> - * could evict as required with minimal stalling) so we are forced
>> - * to idle the GPU and explicitly retire outstanding requests in
>> - * the hopes that we can then remove contexts and the like only
>> - * bound by their active reference.
>> - */
>> - return intel_gt_wait_for_idle(gt, MAX_SCHEDULE_TIMEOUT);
>> + int ret = 0;
>> +
>> + if (i915_is_ggtt(vm)) {
>> + struct i915_ggtt *ggtt = i915_vm_to_ggtt(vm);
>> + struct intel_gt *gt;
>> +
>> + list_for_each_entry(gt, &ggtt->gt_list, ggtt_link) {
>> + /*
>> + * Not everything in the GGTT is tracked via vma (otherwise we
>> + * could evict as required with minimal stalling) so we are forced
>> + * to idle the GPU and explicitly retire outstanding requests in
>> + * the hopes that we can then remove contexts and the like only
>> + * bound by their active reference.
>> + */
>> + ret = intel_gt_wait_for_idle(gt, MAX_SCHEDULE_TIMEOUT);
>> + if (ret)
>> + return ret;
>> + }
>> + } else {
>> + ret = intel_gt_wait_for_idle(vm->gt, MAX_SCHEDULE_TIMEOUT);
>
> This function is only ever got called on the GGTT as far as I can see
> (which makes sense given that its name starts with 'ggtt'). It's not
> clear to me why we want to handle PPGTT too now?
>
Thanks for catching this, it is indeed only used for GGTT, so this
i915_is_ggtt check is not needed.
> Even if this is intentional and correct, it might be best to move this
> up to a small if statement at the top of the function with a return so
> that we can eliminate a level of nesting from most of the function.
>
> if (!i915_is_ggtt(vm)) {
> wait for idle;
> return;
> }
>
> ...
>
>
>> + }
>> + return ret;
>> }
>>
>> static bool grab_vma(struct i915_vma *vma, struct i915_gem_ww_ctx *ww)
>> @@ -149,6 +163,7 @@ i915_gem_evict_something(struct i915_address_space *vm,
>> struct drm_mm_node *node;
>> enum drm_mm_insert_mode mode;
>> struct i915_vma *active;
>> + struct intel_gt *gt;
>> int ret;
>>
>> lockdep_assert_held(&vm->mutex);
>> @@ -174,7 +189,14 @@ i915_gem_evict_something(struct i915_address_space *vm,
>> min_size, alignment, color,
>> start, end, mode);
>>
>> - intel_gt_retire_requests(vm->gt);
>> + if (i915_is_ggtt(vm)) {
>> + struct i915_ggtt *ggtt = i915_vm_to_ggtt(vm);
>> +
>> + list_for_each_entry_rcu(gt, &ggtt->gt_list, ggtt_link)
>> + intel_gt_retire_requests(gt);
>> + } else {
>> + intel_gt_retire_requests(vm->gt);
>> + }
>>
>> search_again:
>> active = NULL;
>> @@ -246,7 +268,7 @@ i915_gem_evict_something(struct i915_address_space *vm,
>> if (I915_SELFTEST_ONLY(igt_evict_ctl.fail_if_busy))
>> return -EBUSY;
>>
>> - ret = ggtt_flush(vm->gt);
>> + ret = ggtt_flush(vm);
>
> As noted above, this call is always done on GGTT (since we checked and
> returned if it wasn't GGTT just before this point in the function).
>
>> if (ret)
>> return ret;
>>
>> @@ -332,7 +354,15 @@ int i915_gem_evict_for_node(struct i915_address_space *vm,
>> * a stray pin (preventing eviction) that can only be resolved by
>> * retiring.
>> */
>> - intel_gt_retire_requests(vm->gt);
>> + if (i915_is_ggtt(vm)) {
>> + struct i915_ggtt *ggtt = i915_vm_to_ggtt(vm);
>> + struct intel_gt *gt;
>> +
>> + list_for_each_entry(gt, &ggtt->gt_list, ggtt_link)
>> + intel_gt_retire_requests(gt);
>> + } else {
>> + intel_gt_retire_requests(vm->gt);
>> + }
>>
>> if (i915_vm_has_cache_coloring(vm)) {
>> /* Expand search to cover neighbouring guard pages (or lack!) */
>> @@ -437,11 +467,10 @@ int i915_gem_evict_vm(struct i915_address_space *vm, struct i915_gem_ww_ctx *ww)
>> * pin themselves inside the global GTT and performing the
>> * switch otherwise is ineffective.
>> */
>> - if (i915_is_ggtt(vm)) {
>> - ret = ggtt_flush(vm->gt);
>> - if (ret)
>> - return ret;
>> - }
>> +
>> + ret = ggtt_flush(vm);
>> + if (ret)
>> + return ret;
>
> It's not clear to me why we're removing the GGTT check here?
with the above change done, this will be restored.
Thanks,
Aravind.
>
>
> Matt
>
>>
>> do {
>> struct i915_vma *vma, *vn;
>> diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c
>> index c39488eb9eeb..24cbee3c1ce5 100644
>> --- a/drivers/gpu/drm/i915/i915_vma.c
>> +++ b/drivers/gpu/drm/i915/i915_vma.c
>> @@ -1542,6 +1542,8 @@ static int __i915_ggtt_pin(struct i915_vma *vma, struct i915_gem_ww_ctx *ww,
>> u32 align, unsigned int flags)
>> {
>> struct i915_address_space *vm = vma->vm;
>> + struct intel_gt *gt;
>> + struct i915_ggtt *ggtt = i915_vm_to_ggtt(vm);
>> int err;
>>
>> do {
>> @@ -1557,7 +1559,8 @@ static int __i915_ggtt_pin(struct i915_vma *vma, struct i915_gem_ww_ctx *ww,
>> }
>>
>> /* Unlike i915_vma_pin, we don't take no for an answer! */
>> - flush_idle_contexts(vm->gt);
>> + list_for_each_entry_rcu(gt, &ggtt->gt_list, ggtt_link)
>> + flush_idle_contexts(gt);
>> if (mutex_lock_interruptible(&vm->mutex) == 0) {
>> /*
>> * We pass NULL ww here, as we don't want to unbind
>> diff --git a/drivers/gpu/drm/i915/selftests/i915_gem.c b/drivers/gpu/drm/i915/selftests/i915_gem.c
>> index e5dd82e7e480..2535b9684bd1 100644
>> --- a/drivers/gpu/drm/i915/selftests/i915_gem.c
>> +++ b/drivers/gpu/drm/i915/selftests/i915_gem.c
>> @@ -127,6 +127,8 @@ static void igt_pm_resume(struct drm_i915_private *i915)
>> */
>> with_intel_runtime_pm(&i915->runtime_pm, wakeref) {
>> i915_ggtt_resume(to_gt(i915)->ggtt);
>> + if (GRAPHICS_VER(i915) >= 8)
>> + setup_private_pat(to_gt(i915));
>> i915_gem_resume(i915);
>> }
>> }
>> diff --git a/drivers/gpu/drm/i915/selftests/mock_gtt.c b/drivers/gpu/drm/i915/selftests/mock_gtt.c
>> index 568840e7ca66..b519d271f4fe 100644
>> --- a/drivers/gpu/drm/i915/selftests/mock_gtt.c
>> +++ b/drivers/gpu/drm/i915/selftests/mock_gtt.c
>> @@ -127,6 +127,7 @@ void mock_init_ggtt(struct intel_gt *gt)
>> ggtt->vm.vma_ops.bind_vma = mock_bind_ggtt;
>> ggtt->vm.vma_ops.unbind_vma = mock_unbind_ggtt;
>>
>> + INIT_LIST_HEAD(&ggtt->gt_list);
>> i915_address_space_init(&ggtt->vm, VM_CLASS_GGTT);
>> }
>>
>> --
>> 2.25.1
>>
>
