[igt-dev] [PATCH i-g-t v3 06/13] lib/intel_batchbuffer: use canonical addresses for 48bit ppgtt

[Zbigniew Kempczyński]

For all EXEC_OBJECT_PINNED objects we need to be sure address
passed must be in canonical form.

Signed-off-by: Zbigniew Kempczyński <zbigniew.kempczynski at intel.com>
Cc: Dominik Grzegorzek <dominik.grzegorzek at intel.com>
Cc: Chris Wilson <chris at chris-wilson.co.uk>
---
 lib/intel_batchbuffer.c   | 21 ++++++++++++++-----
 tests/i915/api_intel_bb.c | 44 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 60 insertions(+), 5 deletions(-)

diff --git a/lib/intel_batchbuffer.c b/lib/intel_batchbuffer.c
index bf84d5f0..19474b06 100644
--- a/lib/intel_batchbuffer.c
+++ b/lib/intel_batchbuffer.c
@@ -1204,6 +1204,20 @@ static void __reallocate_objects(struct intel_bb *ibb)
 	}
 }
 
+/*
+ * gen8_canonical_addr
+ * Used to convert any address into canonical form, i.e. [63:48] == [47].
+ * Based on kernel's sign_extend64 implementation.
+ * @address - a virtual address
+ */
+#define GEN8_HIGH_ADDRESS_BIT 47
+static uint64_t gen8_canonical_addr(uint64_t address)
+{
+	__u8 shift = 63 - GEN8_HIGH_ADDRESS_BIT;
+
+	return (__s64)(address << shift) >> shift;
+}
+
 static inline uint64_t __intel_bb_propose_offset(struct intel_bb *ibb)
 {
 	uint64_t offset;
@@ -1216,6 +1230,7 @@ static inline uint64_t __intel_bb_propose_offset(struct intel_bb *ibb)
 	offset += 256 << 10; /* Keep the low 256k clear, for negative deltas */
 	offset &= ibb->gtt_size - 1;
 	offset &= ~(ibb->alignment - 1);
+	offset = gen8_canonical_addr(offset);
 
 	return offset;
 }
@@ -1499,7 +1514,7 @@ intel_bb_add_object(struct intel_bb *ibb, uint32_t handle,
 	i = ibb->num_objects;
 	object = &ibb->objects[i];
 	object->handle = handle;
-	object->offset = offset;
+	object->offset = gen8_canonical_addr(offset);
 	object->alignment = ibb->alignment;
 
 	found = tsearch((void *) object, &ibb->root, __compare_objects);
@@ -1809,8 +1824,6 @@ static void intel_bb_dump_execbuf(struct intel_bb *ibb,
 			    from_user_pointer(execbuf->buffers_ptr))[i];
 		relocs = from_user_pointer(objects->relocs_ptr);
 		address = objects->offset;
-		if (address != INTEL_BUF_INVALID_ADDRESS)
-			address = address & (ibb->gtt_size - 1);
 		igt_info(" [%d] handle: %u, reloc_count: %d, reloc_ptr: %p, "
 			 "align: 0x%llx, offset: 0x%" PRIx64 ", flags: 0x%llx, "
 			 "rsvd1: 0x%llx, rsvd2: 0x%llx\n",
@@ -1825,8 +1838,6 @@ static void intel_bb_dump_execbuf(struct intel_bb *ibb,
 			for (j = 0; j < objects->relocation_count; j++) {
 				reloc = &relocs[j];
 				address = reloc->presumed_offset;
-				if (address != INTEL_BUF_INVALID_ADDRESS)
-					address = address & (ibb->gtt_size - 1);
 				igt_info("\t [%d] target handle: %u, "
 					 "offset: 0x%llx, delta: 0x%x, "
 					 "presumed_offset: 0x%" PRIx64 ", "
diff --git a/tests/i915/api_intel_bb.c b/tests/i915/api_intel_bb.c
index df0eb933..1a22e8fd 100644
--- a/tests/i915/api_intel_bb.c
+++ b/tests/i915/api_intel_bb.c
@@ -165,6 +165,47 @@ static void simple_bb(struct buf_ops *bops, bool use_context)
 		gem_context_destroy(i915, ctx);
 }
 
+static void check_canonical(struct buf_ops *bops)
+{
+	int i915 = buf_ops_get_fd(bops);
+	struct intel_bb *ibb;
+	struct intel_buf *buf;
+	uint32_t offset;
+	uint64_t gtt_size, address;
+	bool supports_48bit;
+
+	ibb = intel_bb_create(i915, PAGE_SIZE);
+	supports_48bit = ibb->supports_48b_address;
+	if (!supports_48bit)
+		intel_bb_destroy(ibb);
+	igt_require_f(supports_48bit, "We need 48bit ppgtt for testing\n");
+
+	address = 0x800040002000;
+	gtt_size = ibb->gtt_size;
+	if ((address & (gtt_size - 1)) != address)
+		intel_bb_destroy(ibb);
+	igt_require_f((address & (gtt_size - 1)) == address,
+		      "Your ppgtt is not full 48 ppgtt\n");
+
+	if (debug_bb)
+		intel_bb_set_debug(ibb, true);
+
+	offset = intel_bb_emit_bbe(ibb);
+
+	buf = intel_buf_create(bops, 512, 512, 32, 0,
+			       I915_TILING_NONE, I915_COMPRESSION_NONE);
+
+	buf->addr.offset = address;
+	intel_bb_add_intel_buf(ibb, buf, true);
+	intel_bb_object_set_flag(ibb, buf->handle, EXEC_OBJECT_PINNED);
+
+	intel_bb_exec(ibb, offset,
+		      I915_EXEC_DEFAULT | I915_EXEC_NO_RELOC, true);
+
+	intel_buf_destroy(buf);
+	intel_bb_destroy(ibb);
+}
+
 #define MI_FLUSH_DW (0x26<<23)
 #define BCS_SWCTRL  0x22200
 #define BCS_SRC_Y   (1 << 0)
@@ -829,6 +870,9 @@ igt_main_args("dpi", NULL, help_str, opt_handler, NULL)
 	igt_subtest("simple-bb-ctx")
 		simple_bb(bops, true);
 
+	igt_subtest("check-canonical")
+		check_canonical(bops);
+
 	igt_subtest("blit-noreloc-keep-cache")
 		blit(bops, NORELOC, KEEP_CACHE);
 
-- 
2.26.0