drm/amd/display: move vmid determination logic to a module

Currently vmid is decided internally inside dc. With the introduction
of new asics we are required to coordinate vmid use with external
components.

This change converts vmid logic to a DAL module allowing vmid to be
passed in as a parameter to DC.

Signed-off-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Reviewed-by: Charlene Liu <Charlene.Liu@amd.com>
Acked-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

2 files changed, 202 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/display/modules/inc/mod_vmid.h b/drivers/gpu/drm/amd/display/modules/inc/mod_vmid.h
new file mode 100644
index 000000000000..c7672f3b837f
--- /dev/null
+++ b/drivers/gpu/drm/amd/display/modules/inc/mod_vmid.h
@@ -0,0 +1,44 @@
+/*
+ * Copyright 2019 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+#ifndef MOD_VMID_H_
+#define MOD_VMID_H_
+
+#define MAX_VMID 16
+
+#include "dc.h"
+
+struct mod_vmid {
+	int dummy;
+};
+
+uint8_t mod_vmid_get_for_ptb(struct mod_vmid *mod_vmid, uint64_t ptb);
+void mod_vmid_reset(struct mod_vmid *mod_vmid);
+struct mod_vmid *mod_vmid_create(
+		struct dc *dc,
+		unsigned int num_vmid,
+		struct dc_virtual_addr_space_config *va_config);
+
+#endif /* MOD_VMID_H_ */
diff --git a/drivers/gpu/drm/amd/display/modules/vmid/vmid.c b/drivers/gpu/drm/amd/display/modules/vmid/vmid.c
new file mode 100644
index 000000000000..431052626d93
--- /dev/null
+++ b/drivers/gpu/drm/amd/display/modules/vmid/vmid.c
@@ -0,0 +1,158 @@
+/*
+ * Copyright 2019 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+#include "mod_vmid.h"
+
+struct core_vmid {
+	struct mod_vmid public;
+	struct dc *dc;
+
+	unsigned int num_vmid;
+	unsigned int num_vmids_available;
+	uint64_t ptb_assigned_to_vmid[MAX_VMID];
+	struct dc_virtual_addr_space_config base_config;
+};
+
+#define MOD_VMID_TO_CORE(mod_vmid)\
+		container_of(mod_vmid, struct core_vmid, public)
+
+static void add_ptb_to_table(struct core_vmid *core_vmid, unsigned int vmid, uint64_t ptb)
+{
+	core_vmid->ptb_assigned_to_vmid[vmid] = ptb;
+	core_vmid->num_vmids_available--;
+}
+
+static void clear_entry_from_vmid_table(struct core_vmid *core_vmid, unsigned int vmid)
+{
+	core_vmid->ptb_assigned_to_vmid[vmid] = 0;
+	core_vmid->num_vmids_available++;
+}
+
+static void evict_vmids(struct core_vmid *core_vmid)
+{
+	int i;
+	uint16_t ord = dc_get_vmid_use_vector(core_vmid->dc);
+
+	// At this point any positions with value 0 are unused vmids, evict them
+	for (i = 1; i < core_vmid->num_vmid; i++) {
+		if (ord & (1u << i))
+			clear_entry_from_vmid_table(core_vmid, i);
+	}
+}
+
+// Return value of -1 indicates vmid table unitialized or ptb dne in the table
+static int get_existing_vmid_for_ptb(struct core_vmid *core_vmid, uint64_t ptb)
+{
+	int i;
+
+	for (i = 0; i < core_vmid->num_vmid; i++) {
+		if (core_vmid->ptb_assigned_to_vmid[i] == ptb)
+			return i;
+	}
+
+	return -1;
+}
+
+// Expected to be called only when there's an available vmid
+static int get_next_available_vmid(struct core_vmid *core_vmid)
+{
+	int i;
+
+	for (i = 1; i < core_vmid->num_vmid; i++) {
+		if (core_vmid->ptb_assigned_to_vmid[i] == 0)
+			return i;
+	}
+
+	return -1;
+}
+
+uint8_t mod_vmid_get_for_ptb(struct mod_vmid *mod_vmid, uint64_t ptb)
+{
+	struct core_vmid *core_vmid = MOD_VMID_TO_CORE(mod_vmid);
+	unsigned int vmid = 0;
+
+	// Physical address gets vmid 0
+	if (ptb == 0)
+		return 0;
+
+	vmid = get_existing_vmid_for_ptb(core_vmid, ptb);
+
+	if (vmid == -1) {
+		struct dc_virtual_addr_space_config va_config = core_vmid->base_config;
+
+		va_config.page_table_base_addr = ptb;
+
+		if (core_vmid->num_vmids_available == 0)
+			evict_vmids(core_vmid);
+
+		vmid = get_next_available_vmid(core_vmid);
+		add_ptb_to_table(core_vmid, vmid, ptb);
+
+		dc_setup_vm_context(core_vmid->dc, &va_config, vmid);
+	}
+
+	return vmid;
+}
+
+void mod_vmid_reset(struct mod_vmid *mod_vmid)
+{
+	struct core_vmid *core_vmid = MOD_VMID_TO_CORE(mod_vmid);
+
+	core_vmid->num_vmids_available = core_vmid->num_vmid - 1;
+	memset(core_vmid->ptb_assigned_to_vmid, 0, sizeof(core_vmid->ptb_assigned_to_vmid[0]) * MAX_VMID);
+}
+
+struct mod_vmid *mod_vmid_create(
+		struct dc *dc,
+		unsigned int num_vmid,
+		struct dc_virtual_addr_space_config *va_config)
+{
+	struct core_vmid *core_vmid;
+
+	if (num_vmid <= 1)
+		goto fail_no_vm_ctx;
+
+	if (dc == NULL)
+		goto fail_dc_null;
+
+	core_vmid = kzalloc(sizeof(struct core_vmid), GFP_KERNEL);
+
+	if (core_vmid == NULL)
+		goto fail_alloc_context;
+
+	core_vmid->dc = dc;
+	core_vmid->num_vmid = num_vmid;
+	core_vmid->num_vmids_available = num_vmid - 1;
+	core_vmid->base_config = *va_config;
+
+	memset(core_vmid->ptb_assigned_to_vmid, 0, sizeof(core_vmid->ptb_assigned_to_vmid[0]) * MAX_VMID);
+
+	return &core_vmid->public;
+
+fail_no_vm_ctx:
+fail_alloc_context:
+fail_dc_null:
+	return NULL;
+}