Re: [Intel-gfx] [PATCH 4/4] drm/i915/gt: nuke gen6_hw_id

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




On 21/07/2021 19:44, Lucas De Marchi wrote:
On Wed, Jul 21, 2021 at 10:25:59AM +0100, Tvrtko Ursulin wrote:

On 21/07/2021 00:20, Lucas De Marchi wrote:
This is only used by GRAPHICS_VER == 6 and GRAPHICS_VER == 7. All other
recent platforms do not depend on this field, so it doesn't make much
sense to keep it generic like that. Instead, just do a mapping from
engine class to HW ID in the single place that is needed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@xxxxxxxxx>
---
 drivers/gpu/drm/i915/gt/intel_engine_cs.c    | 6 ------
 drivers/gpu/drm/i915/gt/intel_engine_types.h | 8 --------
 drivers/gpu/drm/i915/i915_reg.h              | 4 +++-
 3 files changed, 3 insertions(+), 15 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
index 508221de411c..0a04e8d90e9e 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
@@ -42,7 +42,6 @@
 #define MAX_MMIO_BASES 3
 struct engine_info {
-    u8 gen6_hw_id;
     u8 class;
     u8 instance;
     /* mmio bases table *must* be sorted in reverse graphics_ver order */
@@ -54,7 +53,6 @@ struct engine_info {
 static const struct engine_info intel_engines[] = {
     [RCS0] = {
-        .gen6_hw_id = RCS0_HW,
         .class = RENDER_CLASS,
         .instance = 0,
         .mmio_bases = {
@@ -62,7 +60,6 @@ static const struct engine_info intel_engines[] = {
         },
     },
     [BCS0] = {
-        .gen6_hw_id = BCS0_HW,
         .class = COPY_ENGINE_CLASS,
         .instance = 0,
         .mmio_bases = {
@@ -70,7 +67,6 @@ static const struct engine_info intel_engines[] = {
         },
     },
     [VCS0] = {
-        .gen6_hw_id = VCS0_HW,
         .class = VIDEO_DECODE_CLASS,
         .instance = 0,
         .mmio_bases = {
@@ -102,7 +98,6 @@ static const struct engine_info intel_engines[] = {
         },
     },
     [VECS0] = {
-        .gen6_hw_id = VECS0_HW,
         .class = VIDEO_ENHANCEMENT_CLASS,
         .instance = 0,
         .mmio_bases = {
@@ -290,7 +285,6 @@ static int intel_engine_setup(struct intel_gt *gt, enum intel_engine_id id)
     engine->i915 = i915;
     engine->gt = gt;
     engine->uncore = gt->uncore;
-    engine->gen6_hw_id = info->gen6_hw_id;
     guc_class = engine_class_to_guc_class(info->class);
     engine->guc_id = MAKE_GUC_ID(guc_class, info->instance);
     engine->mmio_base = __engine_mmio_base(i915, info->mmio_bases);
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_types.h b/drivers/gpu/drm/i915/gt/intel_engine_types.h
index 266422d8d1b1..64330bfb7641 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_types.h
+++ b/drivers/gpu/drm/i915/gt/intel_engine_types.h
@@ -28,13 +28,6 @@
 #include "intel_wakeref.h"
 #include "intel_workarounds_types.h"
-/* Legacy HW Engine ID */
-
-#define RCS0_HW        0
-#define VCS0_HW        1
-#define BCS0_HW        2
-#define VECS0_HW    3
-
 /* Gen11+ HW Engine class + instance */
 #define RENDER_CLASS        0
 #define VIDEO_DECODE_CLASS    1
@@ -268,7 +261,6 @@ struct intel_engine_cs {
     intel_engine_mask_t mask;
-    u8 gen6_hw_id;
     u8 class;
     u8 instance;
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 8750ffce9d61..d91386f4828e 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -2572,7 +2572,9 @@ static inline bool i915_mmio_reg_valid(i915_reg_t reg)
 #define   ARB_MODE_BWGTLB_DISABLE (1 << 9)
 #define   ARB_MODE_SWIZZLE_BDW    (1 << 1)
 #define RENDER_HWS_PGA_GEN7    _MMIO(0x04080)
-#define RING_FAULT_REG(engine)    _MMIO(0x4094 + 0x100 * (engine)->gen6_hw_id)
+
+#define _GEN6_ENGINE_CLASS_TO_ID(class) _PICK((class), 0, 1, 3, 2)
+#define RING_FAULT_REG(engine)    _MMIO(0x4094 + 0x100 * _GEN6_ENGINE_CLASS_TO_ID((engine)->class))

Makes sense to me.

Maybe HW_ID and HW_CLASS in the macro name? Not sure.

I can do that... I think I avoided it because it makes the macro
very big. Anyway, this should be called in just one place, so it doesn't
matter much... I can add it.


Only open I have is why the "Gen11+ HW Engine class + instance" comment and now we would tie that, allegedly Gen11 concept, with Gen6-7. Care to do some digging?

Not sure. This comes from 3d7b3039741d ("drm/i915: Move engine IDs out of i915_reg.h")
that I reviewed :-o

Cc'ing  Daniele. I don't see "class" as a Gen11+ thing. Is it just that
those numbers started to make sense for gen11?  Since

a) we are using the class even for GRAPHICS_VER < 11
b) the legacy HW IDs shouldn't be used anywhere else anymore


we could

1) move the legacy defines back to i915_reg.h
2) use them in the macro above (IMO would slightly improve the
readability of that _PICK() call)
3) Remove the "Gen11+" comment in the _CLASS macros to avoid
misunderstandings


Thoughts?

What Matt suggested sounds fine to me (using _PICK with _RING_FAULT_REG_RCS etc). It retires the concept of hw id from the code base completely and hopefully the need for it does not re-surface.

Regards,

Tvrtko



[Index of Archives]     [Linux DRI Users]     [Linux Intel Graphics]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]
  Powered by Linux