drm/msm: Add SDM845 DPU support

SDM845 SoC includes the Mobile Display Sub System (MDSS) which is a
top level wrapper consisting of Display Processing Unit (DPU) and
display peripheral modules such as Display Serial Interface (DSI)
and DisplayPort (DP).

MDSS functions essentially as a back-end composition engine. It blends
video and graphic images stored in the frame buffers and scans out the
composed image to a display sink (over DSI/DP).

The following diagram represents hardware blocks for a simple pipeline
(two planes are present on a given crtc which is connected to a DSI
connector):

       MDSS
      +---------------------------------+
      | +-----------------------------+ |
      | | DPU                         | |
      | |  +--------+  +--------+     | |
      | |  |  SSPP  |  |  SSPP  |     | |
      | |  +----+---+  +----+---+     | |
      | |       |           |         | |
      | |  +----v-----------v---+     | |
      | |  |  Layer Mixer (LM)  |     | |
      | |  +--------------------+     | |
      | |  +--------------------+     | |
      | |  |    PingPong (PP)   |     | |
      | |  +--------------------+     | |
      | |  +--------------------+     | |
      | |  |  INTERFACE (VIDEO) |     | |
      | |  +---+----------------+     | |
      | +------|----------------------+ |
      |        |                        |
      | +------|---------------------+  |
      | |      | DISPLAY PERIPHERALS |  |
      | |  +---v-+      +-----+      |  |
      | |  | DSI |      |  DP |      |  |
      | |  +-----+      +-----+      |  |
      | +----------------------------+  |
      +---------------------------------+

The number of DPU sub-blocks (i.e. SSPPs, LMs, PP blocks and INTFs)
depends on SoC capabilities.

Overview of DPU sub-blocks:
---------------------------
* Source Surface Processor (SSPP):
 Refers to any of hardware pipes like ViG, DMA etc. Only ViG pipes are
 capable of performing format conversion, scaling and quality improvement
 for source surfaces.

* Layer Mixer (LM):
 Blend source surfaces together (in requested zorder)

* PingPong (PP):
 This block controls frame done interrupt output, EOL and EOF generation,
 overflow/underflow control.

* Display interface (INTF):
 Timing generator and interface connecting the display peripherals.

DRM components mapping to DPU architecture:
------------------------------------------
PLANEs maps to SSPPs
CRTC maps to LMs
Encoder maps to PPs, INTFs

Data flow setup:
---------------
MDSS hardware can support various data flows (e.g.):
  - Dual pipe: Output from two LMs combined to single display.
  - Split display: Output from two LMs connected to two separate
                   interfaces.

The hardware capabilities determine the number of concurrent data paths
possible. Any control path (i.e. pipeline w/i DPU) can be routed to any
of the hardware data paths. A given control path can be triggered,
flushed and controlled independently.

Changes in v3:
- Move msm_media_info.h from uapi to dpu/ subdir
- Remove preclose callback dpu (it's handled in core)
- Fix kbuild warnings with parent_ops
- Remove unused functions from dpu_core_irq
- Rename mdss_phys to mdss
- Rename mdp_phys address space to mdp
- Drop _phys from vbif and regdma binding names

Signed-off-by: Abhinav Kumar <abhinavk@codeaurora.org>
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Chandan Uddaraju <chandanu@codeaurora.org>
Signed-off-by: Jeykumar Sankaran <jsanka@codeaurora.org>
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rajesh Yadav <ryadav@codeaurora.org>
Signed-off-by: Sravanthi Kollukuduru <skolluku@codeaurora.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
[robclark minor rebase]
Signed-off-by: Rob Clark <robdclark@gmail.com>

1 files changed, 1079 insertions, 0 deletions

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
new file mode 100644
index 000000000000..13c0a36d4ef9
--- /dev/null
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
@@ -0,0 +1,1079 @@
+/*
+ * Copyright (c) 2016-2018, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#define pr_fmt(fmt)	"[drm:%s] " fmt, __func__
+#include "dpu_kms.h"
+#include "dpu_hw_lm.h"
+#include "dpu_hw_ctl.h"
+#include "dpu_hw_cdm.h"
+#include "dpu_hw_pingpong.h"
+#include "dpu_hw_intf.h"
+#include "dpu_encoder.h"
+#include "dpu_trace.h"
+
+#define RESERVED_BY_OTHER(h, r) \
+	((h)->rsvp && ((h)->rsvp->enc_id != (r)->enc_id))
+
+#define RM_RQ_LOCK(r) ((r)->top_ctrl & BIT(DPU_RM_TOPCTL_RESERVE_LOCK))
+#define RM_RQ_CLEAR(r) ((r)->top_ctrl & BIT(DPU_RM_TOPCTL_RESERVE_CLEAR))
+#define RM_RQ_DS(r) ((r)->top_ctrl & BIT(DPU_RM_TOPCTL_DS))
+#define RM_IS_TOPOLOGY_MATCH(t, r) ((t).num_lm == (r).num_lm && \
+				(t).num_comp_enc == (r).num_enc && \
+				(t).num_intf == (r).num_intf)
+
+struct dpu_rm_topology_def {
+	enum dpu_rm_topology_name top_name;
+	int num_lm;
+	int num_comp_enc;
+	int num_intf;
+	int num_ctl;
+	int needs_split_display;
+};
+
+static const struct dpu_rm_topology_def g_top_table[] = {
+	{   DPU_RM_TOPOLOGY_NONE,                 0, 0, 0, 0, false },
+	{   DPU_RM_TOPOLOGY_SINGLEPIPE,           1, 0, 1, 1, false },
+	{   DPU_RM_TOPOLOGY_DUALPIPE,             2, 0, 2, 2, true  },
+	{   DPU_RM_TOPOLOGY_DUALPIPE_3DMERGE,     2, 0, 1, 1, false },
+};
+
+/**
+ * struct dpu_rm_requirements - Reservation requirements parameter bundle
+ * @top_ctrl:  topology control preference from kernel client
+ * @top:       selected topology for the display
+ * @hw_res:	   Hardware resources required as reported by the encoders
+ */
+struct dpu_rm_requirements {
+	uint64_t top_ctrl;
+	const struct dpu_rm_topology_def *topology;
+	struct dpu_encoder_hw_resources hw_res;
+};
+
+/**
+ * struct dpu_rm_rsvp - Use Case Reservation tagging structure
+ *	Used to tag HW blocks as reserved by a CRTC->Encoder->Connector chain
+ *	By using as a tag, rather than lists of pointers to HW blocks used
+ *	we can avoid some list management since we don't know how many blocks
+ *	of each type a given use case may require.
+ * @list:	List head for list of all reservations
+ * @seq:	Global RSVP sequence number for debugging, especially for
+ *		differentiating differenct allocations for same encoder.
+ * @enc_id:	Reservations are tracked by Encoder DRM object ID.
+ *		CRTCs may be connected to multiple Encoders.
+ *		An encoder or connector id identifies the display path.
+ * @topology	DRM<->HW topology use case
+ */
+struct dpu_rm_rsvp {
+	struct list_head list;
+	uint32_t seq;
+	uint32_t enc_id;
+	enum dpu_rm_topology_name topology;
+};
+
+/**
+ * struct dpu_rm_hw_blk - hardware block tracking list member
+ * @list:	List head for list of all hardware blocks tracking items
+ * @rsvp:	Pointer to use case reservation if reserved by a client
+ * @rsvp_nxt:	Temporary pointer used during reservation to the incoming
+ *		request. Will be swapped into rsvp if proposal is accepted
+ * @type:	Type of hardware block this structure tracks
+ * @id:		Hardware ID number, within it's own space, ie. LM_X
+ * @catalog:	Pointer to the hardware catalog entry for this block
+ * @hw:		Pointer to the hardware register access object for this block
+ */
+struct dpu_rm_hw_blk {
+	struct list_head list;
+	struct dpu_rm_rsvp *rsvp;
+	struct dpu_rm_rsvp *rsvp_nxt;
+	enum dpu_hw_blk_type type;
+	uint32_t id;
+	struct dpu_hw_blk *hw;
+};
+
+/**
+ * dpu_rm_dbg_rsvp_stage - enum of steps in making reservation for event logging
+ */
+enum dpu_rm_dbg_rsvp_stage {
+	DPU_RM_STAGE_BEGIN,
+	DPU_RM_STAGE_AFTER_CLEAR,
+	DPU_RM_STAGE_AFTER_RSVPNEXT,
+	DPU_RM_STAGE_FINAL
+};
+
+static void _dpu_rm_print_rsvps(
+		struct dpu_rm *rm,
+		enum dpu_rm_dbg_rsvp_stage stage)
+{
+	struct dpu_rm_rsvp *rsvp;
+	struct dpu_rm_hw_blk *blk;
+	enum dpu_hw_blk_type type;
+
+	DPU_DEBUG("%d\n", stage);
+
+	list_for_each_entry(rsvp, &rm->rsvps, list) {
+		DRM_DEBUG_KMS("%d rsvp[s%ue%u] topology %d\n", stage, rsvp->seq,
+			      rsvp->enc_id, rsvp->topology);
+	}
+
+	for (type = 0; type < DPU_HW_BLK_MAX; type++) {
+		list_for_each_entry(blk, &rm->hw_blks[type], list) {
+			if (!blk->rsvp && !blk->rsvp_nxt)
+				continue;
+
+			DRM_DEBUG_KMS("%d rsvp[s%ue%u->s%ue%u] %d %d\n", stage,
+				(blk->rsvp) ? blk->rsvp->seq : 0,
+				(blk->rsvp) ? blk->rsvp->enc_id : 0,
+				(blk->rsvp_nxt) ? blk->rsvp_nxt->seq : 0,
+				(blk->rsvp_nxt) ? blk->rsvp_nxt->enc_id : 0,
+				blk->type, blk->id);
+		}
+	}
+}
+
+struct dpu_hw_mdp *dpu_rm_get_mdp(struct dpu_rm *rm)
+{
+	return rm->hw_mdp;
+}
+
+enum dpu_rm_topology_name
+dpu_rm_get_topology_name(struct msm_display_topology topology)
+{
+	int i;
+
+	for (i = 0; i < DPU_RM_TOPOLOGY_MAX; i++)
+		if (RM_IS_TOPOLOGY_MATCH(g_top_table[i], topology))
+			return g_top_table[i].top_name;
+
+	return DPU_RM_TOPOLOGY_NONE;
+}
+
+void dpu_rm_init_hw_iter(
+		struct dpu_rm_hw_iter *iter,
+		uint32_t enc_id,
+		enum dpu_hw_blk_type type)
+{
+	memset(iter, 0, sizeof(*iter));
+	iter->enc_id = enc_id;
+	iter->type = type;
+}
+
+static bool _dpu_rm_get_hw_locked(struct dpu_rm *rm, struct dpu_rm_hw_iter *i)
+{
+	struct list_head *blk_list;
+
+	if (!rm || !i || i->type >= DPU_HW_BLK_MAX) {
+		DPU_ERROR("invalid rm\n");
+		return false;
+	}
+
+	i->hw = NULL;
+	blk_list = &rm->hw_blks[i->type];
+
+	if (i->blk && (&i->blk->list == blk_list)) {
+		DPU_DEBUG("attempt resume iteration past last\n");
+		return false;
+	}
+
+	i->blk = list_prepare_entry(i->blk, blk_list, list);
+
+	list_for_each_entry_continue(i->blk, blk_list, list) {
+		struct dpu_rm_rsvp *rsvp = i->blk->rsvp;
+
+		if (i->blk->type != i->type) {
+			DPU_ERROR("found incorrect block type %d on %d list\n",
+					i->blk->type, i->type);
+			return false;
+		}
+
+		if ((i->enc_id == 0) || (rsvp && rsvp->enc_id == i->enc_id)) {
+			i->hw = i->blk->hw;
+			DPU_DEBUG("found type %d id %d for enc %d\n",
+					i->type, i->blk->id, i->enc_id);
+			return true;
+		}
+	}
+
+	DPU_DEBUG("no match, type %d for enc %d\n", i->type, i->enc_id);
+
+	return false;
+}
+
+bool dpu_rm_get_hw(struct dpu_rm *rm, struct dpu_rm_hw_iter *i)
+{
+	bool ret;
+
+	mutex_lock(&rm->rm_lock);
+	ret = _dpu_rm_get_hw_locked(rm, i);
+	mutex_unlock(&rm->rm_lock);
+
+	return ret;
+}
+
+static void _dpu_rm_hw_destroy(enum dpu_hw_blk_type type, void *hw)
+{
+	switch (type) {
+	case DPU_HW_BLK_LM:
+		dpu_hw_lm_destroy(hw);
+		break;
+	case DPU_HW_BLK_CTL:
+		dpu_hw_ctl_destroy(hw);
+		break;
+	case DPU_HW_BLK_CDM:
+		dpu_hw_cdm_destroy(hw);
+		break;
+	case DPU_HW_BLK_PINGPONG:
+		dpu_hw_pingpong_destroy(hw);
+		break;
+	case DPU_HW_BLK_INTF:
+		dpu_hw_intf_destroy(hw);
+		break;
+	case DPU_HW_BLK_SSPP:
+		/* SSPPs are not managed by the resource manager */
+	case DPU_HW_BLK_TOP:
+		/* Top is a singleton, not managed in hw_blks list */
+	case DPU_HW_BLK_MAX:
+	default:
+		DPU_ERROR("unsupported block type %d\n", type);
+		break;
+	}
+}
+
+int dpu_rm_destroy(struct dpu_rm *rm)
+{
+
+	struct dpu_rm_rsvp *rsvp_cur, *rsvp_nxt;
+	struct dpu_rm_hw_blk *hw_cur, *hw_nxt;
+	enum dpu_hw_blk_type type;
+
+	if (!rm) {
+		DPU_ERROR("invalid rm\n");
+		return -EINVAL;
+	}
+
+	list_for_each_entry_safe(rsvp_cur, rsvp_nxt, &rm->rsvps, list) {
+		list_del(&rsvp_cur->list);
+		kfree(rsvp_cur);
+	}
+
+
+	for (type = 0; type < DPU_HW_BLK_MAX; type++) {
+		list_for_each_entry_safe(hw_cur, hw_nxt, &rm->hw_blks[type],
+				list) {
+			list_del(&hw_cur->list);
+			_dpu_rm_hw_destroy(hw_cur->type, hw_cur->hw);
+			kfree(hw_cur);
+		}
+	}
+
+	dpu_hw_mdp_destroy(rm->hw_mdp);
+	rm->hw_mdp = NULL;
+
+	mutex_destroy(&rm->rm_lock);
+
+	return 0;
+}
+
+static int _dpu_rm_hw_blk_create(
+		struct dpu_rm *rm,
+		struct dpu_mdss_cfg *cat,
+		void __iomem *mmio,
+		enum dpu_hw_blk_type type,
+		uint32_t id,
+		void *hw_catalog_info)
+{
+	struct dpu_rm_hw_blk *blk;
+	struct dpu_hw_mdp *hw_mdp;
+	void *hw;
+
+	hw_mdp = rm->hw_mdp;
+
+	switch (type) {
+	case DPU_HW_BLK_LM:
+		hw = dpu_hw_lm_init(id, mmio, cat);
+		break;
+	case DPU_HW_BLK_CTL:
+		hw = dpu_hw_ctl_init(id, mmio, cat);
+		break;
+	case DPU_HW_BLK_CDM:
+		hw = dpu_hw_cdm_init(id, mmio, cat, hw_mdp);
+		break;
+	case DPU_HW_BLK_PINGPONG:
+		hw = dpu_hw_pingpong_init(id, mmio, cat);
+		break;
+	case DPU_HW_BLK_INTF:
+		hw = dpu_hw_intf_init(id, mmio, cat);
+		break;
+	case DPU_HW_BLK_SSPP:
+		/* SSPPs are not managed by the resource manager */
+	case DPU_HW_BLK_TOP:
+		/* Top is a singleton, not managed in hw_blks list */
+	case DPU_HW_BLK_MAX:
+	default:
+		DPU_ERROR("unsupported block type %d\n", type);
+		return -EINVAL;
+	}
+
+	if (IS_ERR_OR_NULL(hw)) {
+		DPU_ERROR("failed hw object creation: type %d, err %ld\n",
+				type, PTR_ERR(hw));
+		return -EFAULT;
+	}
+
+	blk = kzalloc(sizeof(*blk), GFP_KERNEL);
+	if (!blk) {
+		_dpu_rm_hw_destroy(type, hw);
+		return -ENOMEM;
+	}
+
+	blk->type = type;
+	blk->id = id;
+	blk->hw = hw;
+	list_add_tail(&blk->list, &rm->hw_blks[type]);
+
+	return 0;
+}
+
+int dpu_rm_init(struct dpu_rm *rm,
+		struct dpu_mdss_cfg *cat,
+		void __iomem *mmio,
+		struct drm_device *dev)
+{
+	int rc, i;
+	enum dpu_hw_blk_type type;
+
+	if (!rm || !cat || !mmio || !dev) {
+		DPU_ERROR("invalid kms\n");
+		return -EINVAL;
+	}
+
+	/* Clear, setup lists */
+	memset(rm, 0, sizeof(*rm));
+
+	mutex_init(&rm->rm_lock);
+
+	INIT_LIST_HEAD(&rm->rsvps);
+	for (type = 0; type < DPU_HW_BLK_MAX; type++)
+		INIT_LIST_HEAD(&rm->hw_blks[type]);
+
+	rm->dev = dev;
+
+	/* Some of the sub-blocks require an mdptop to be created */
+	rm->hw_mdp = dpu_hw_mdptop_init(MDP_TOP, mmio, cat);
+	if (IS_ERR_OR_NULL(rm->hw_mdp)) {
+		rc = PTR_ERR(rm->hw_mdp);
+		rm->hw_mdp = NULL;
+		DPU_ERROR("failed: mdp hw not available\n");
+		goto fail;
+	}
+
+	/* Interrogate HW catalog and create tracking items for hw blocks */
+	for (i = 0; i < cat->mixer_count; i++) {
+		struct dpu_lm_cfg *lm = &cat->mixer[i];
+
+		if (lm->pingpong == PINGPONG_MAX) {
+			DPU_DEBUG("skip mixer %d without pingpong\n", lm->id);
+			continue;
+		}
+
+		rc = _dpu_rm_hw_blk_create(rm, cat, mmio, DPU_HW_BLK_LM,
+				cat->mixer[i].id, &cat->mixer[i]);
+		if (rc) {
+			DPU_ERROR("failed: lm hw not available\n");
+			goto fail;
+		}
+
+		if (!rm->lm_max_width) {
+			rm->lm_max_width = lm->sblk->maxwidth;
+		} else if (rm->lm_max_width != lm->sblk->maxwidth) {
+			/*
+			 * Don't expect to have hw where lm max widths differ.
+			 * If found, take the min.
+			 */
+			DPU_ERROR("unsupported: lm maxwidth differs\n");
+			if (rm->lm_max_width > lm->sblk->maxwidth)
+				rm->lm_max_width = lm->sblk->maxwidth;
+		}
+	}
+
+	for (i = 0; i < cat->pingpong_count; i++) {
+		rc = _dpu_rm_hw_blk_create(rm, cat, mmio, DPU_HW_BLK_PINGPONG,
+				cat->pingpong[i].id, &cat->pingpong[i]);
+		if (rc) {
+			DPU_ERROR("failed: pp hw not available\n");
+			goto fail;
+		}
+	}
+
+	for (i = 0; i < cat->intf_count; i++) {
+		if (cat->intf[i].type == INTF_NONE) {
+			DPU_DEBUG("skip intf %d with type none\n", i);
+			continue;
+		}
+
+		rc = _dpu_rm_hw_blk_create(rm, cat, mmio, DPU_HW_BLK_INTF,
+				cat->intf[i].id, &cat->intf[i]);
+		if (rc) {
+			DPU_ERROR("failed: intf hw not available\n");
+			goto fail;
+		}
+	}
+
+	for (i = 0; i < cat->ctl_count; i++) {
+		rc = _dpu_rm_hw_blk_create(rm, cat, mmio, DPU_HW_BLK_CTL,
+				cat->ctl[i].id, &cat->ctl[i]);
+		if (rc) {
+			DPU_ERROR("failed: ctl hw not available\n");
+			goto fail;
+		}
+	}
+
+	for (i = 0; i < cat->cdm_count; i++) {
+		rc = _dpu_rm_hw_blk_create(rm, cat, mmio, DPU_HW_BLK_CDM,
+				cat->cdm[i].id, &cat->cdm[i]);
+		if (rc) {
+			DPU_ERROR("failed: cdm hw not available\n");
+			goto fail;
+		}
+	}
+
+	return 0;
+
+fail:
+	dpu_rm_destroy(rm);
+
+	return rc;
+}
+
+/**
+ * _dpu_rm_check_lm_and_get_connected_blks - check if proposed layer mixer meets
+ *	proposed use case requirements, incl. hardwired dependent blocks like
+ *	pingpong
+ * @rm: dpu resource manager handle
+ * @rsvp: reservation currently being created
+ * @reqs: proposed use case requirements
+ * @lm: proposed layer mixer, function checks if lm, and all other hardwired
+ *      blocks connected to the lm (pp) is available and appropriate
+ * @pp: output parameter, pingpong block attached to the layer mixer.
+ *      NULL if pp was not available, or not matching requirements.
+ * @primary_lm: if non-null, this function check if lm is compatible primary_lm
+ *              as well as satisfying all other requirements
+ * @Return: true if lm matches all requirements, false otherwise
+ */
+static bool _dpu_rm_check_lm_and_get_connected_blks(
+		struct dpu_rm *rm,
+		struct dpu_rm_rsvp *rsvp,
+		struct dpu_rm_requirements *reqs,
+		struct dpu_rm_hw_blk *lm,
+		struct dpu_rm_hw_blk **pp,
+		struct dpu_rm_hw_blk *primary_lm)
+{
+	const struct dpu_lm_cfg *lm_cfg = to_dpu_hw_mixer(lm->hw)->cap;
+	struct dpu_rm_hw_iter iter;
+
+	*pp = NULL;
+
+	DPU_DEBUG("check lm %d pp %d\n",
+			   lm_cfg->id, lm_cfg->pingpong);
+
+	/* Check if this layer mixer is a peer of the proposed primary LM */
+	if (primary_lm) {
+		const struct dpu_lm_cfg *prim_lm_cfg =
+				to_dpu_hw_mixer(primary_lm->hw)->cap;
+
+		if (!test_bit(lm_cfg->id, &prim_lm_cfg->lm_pair_mask)) {
+			DPU_DEBUG("lm %d not peer of lm %d\n", lm_cfg->id,
+					prim_lm_cfg->id);
+			return false;
+		}
+	}
+
+	/* Already reserved? */
+	if (RESERVED_BY_OTHER(lm, rsvp)) {
+		DPU_DEBUG("lm %d already reserved\n", lm_cfg->id);
+		return false;
+	}
+
+	dpu_rm_init_hw_iter(&iter, 0, DPU_HW_BLK_PINGPONG);
+	while (_dpu_rm_get_hw_locked(rm, &iter)) {
+		if (iter.blk->id == lm_cfg->pingpong) {
+			*pp = iter.blk;
+			break;
+		}
+	}
+
+	if (!*pp) {
+		DPU_ERROR("failed to get pp on lm %d\n", lm_cfg->pingpong);
+		return false;
+	}
+
+	if (RESERVED_BY_OTHER(*pp, rsvp)) {
+		DPU_DEBUG("lm %d pp %d already reserved\n", lm->id,
+				(*pp)->id);
+		return false;
+	}
+
+	return true;
+}
+
+static int _dpu_rm_reserve_lms(
+		struct dpu_rm *rm,
+		struct dpu_rm_rsvp *rsvp,
+		struct dpu_rm_requirements *reqs)
+
+{
+	struct dpu_rm_hw_blk *lm[MAX_BLOCKS];
+	struct dpu_rm_hw_blk *pp[MAX_BLOCKS];
+	struct dpu_rm_hw_iter iter_i, iter_j;
+	int lm_count = 0;
+	int i, rc = 0;
+
+	if (!reqs->topology->num_lm) {
+		DPU_ERROR("invalid number of lm: %d\n", reqs->topology->num_lm);
+		return -EINVAL;
+	}
+
+	/* Find a primary mixer */
+	dpu_rm_init_hw_iter(&iter_i, 0, DPU_HW_BLK_LM);
+	while (lm_count != reqs->topology->num_lm &&
+			_dpu_rm_get_hw_locked(rm, &iter_i)) {
+		memset(&lm, 0, sizeof(lm));
+		memset(&pp, 0, sizeof(pp));
+
+		lm_count = 0;
+		lm[lm_count] = iter_i.blk;
+
+		if (!_dpu_rm_check_lm_and_get_connected_blks(
+				rm, rsvp, reqs, lm[lm_count],
+				&pp[lm_count], NULL))
+			continue;
+
+		++lm_count;
+
+		/* Valid primary mixer found, find matching peers */
+		dpu_rm_init_hw_iter(&iter_j, 0, DPU_HW_BLK_LM);
+
+		while (lm_count != reqs->topology->num_lm &&
+				_dpu_rm_get_hw_locked(rm, &iter_j)) {
+			if (iter_i.blk == iter_j.blk)
+				continue;
+
+			if (!_dpu_rm_check_lm_and_get_connected_blks(
+					rm, rsvp, reqs, iter_j.blk,
+					&pp[lm_count], iter_i.blk))
+				continue;
+
+			lm[lm_count] = iter_j.blk;
+			++lm_count;
+		}
+	}
+
+	if (lm_count != reqs->topology->num_lm) {
+		DPU_DEBUG("unable to find appropriate mixers\n");
+		return -ENAVAIL;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(lm); i++) {
+		if (!lm[i])
+			break;
+
+		lm[i]->rsvp_nxt = rsvp;
+		pp[i]->rsvp_nxt = rsvp;
+
+		trace_dpu_rm_reserve_lms(lm[i]->id, lm[i]->type, rsvp->enc_id,
+					 pp[i]->id);
+	}
+
+	return rc;
+}
+
+static int _dpu_rm_reserve_ctls(
+		struct dpu_rm *rm,
+		struct dpu_rm_rsvp *rsvp,
+		const struct dpu_rm_topology_def *top)
+{
+	struct dpu_rm_hw_blk *ctls[MAX_BLOCKS];
+	struct dpu_rm_hw_iter iter;
+	int i = 0;
+
+	memset(&ctls, 0, sizeof(ctls));
+
+	dpu_rm_init_hw_iter(&iter, 0, DPU_HW_BLK_CTL);
+	while (_dpu_rm_get_hw_locked(rm, &iter)) {
+		const struct dpu_hw_ctl *ctl = to_dpu_hw_ctl(iter.blk->hw);
+		unsigned long features = ctl->caps->features;
+		bool has_split_display;
+
+		if (RESERVED_BY_OTHER(iter.blk, rsvp))
+			continue;
+
+		has_split_display = BIT(DPU_CTL_SPLIT_DISPLAY) & features;
+
+		DPU_DEBUG("ctl %d caps 0x%lX\n", iter.blk->id, features);
+
+		if (top->needs_split_display != has_split_display)
+			continue;
+
+		ctls[i] = iter.blk;
+		DPU_DEBUG("ctl %d match\n", iter.blk->id);
+
+		if (++i == top->num_ctl)
+			break;
+	}
+
+	if (i != top->num_ctl)
+		return -ENAVAIL;
+
+	for (i = 0; i < ARRAY_SIZE(ctls) && i < top->num_ctl; i++) {
+		ctls[i]->rsvp_nxt = rsvp;
+		trace_dpu_rm_reserve_ctls(ctls[i]->id, ctls[i]->type,
+					  rsvp->enc_id);
+	}
+
+	return 0;
+}
+
+static int _dpu_rm_reserve_cdm(
+		struct dpu_rm *rm,
+		struct dpu_rm_rsvp *rsvp,
+		uint32_t id,
+		enum dpu_hw_blk_type type)
+{
+	struct dpu_rm_hw_iter iter;
+
+	DRM_DEBUG_KMS("type %d id %d\n", type, id);
+
+	dpu_rm_init_hw_iter(&iter, 0, DPU_HW_BLK_CDM);
+	while (_dpu_rm_get_hw_locked(rm, &iter)) {
+		const struct dpu_hw_cdm *cdm = to_dpu_hw_cdm(iter.blk->hw);
+		const struct dpu_cdm_cfg *caps = cdm->caps;
+		bool match = false;
+
+		if (RESERVED_BY_OTHER(iter.blk, rsvp))
+			continue;
+
+		if (type == DPU_HW_BLK_INTF && id != INTF_MAX)
+			match = test_bit(id, &caps->intf_connect);
+
+		DRM_DEBUG_KMS("iter: type:%d id:%d enc:%d cdm:%lu match:%d\n",
+			      iter.blk->type, iter.blk->id, rsvp->enc_id,
+			      caps->intf_connect, match);
+
+		if (!match)
+			continue;
+
+		trace_dpu_rm_reserve_cdm(iter.blk->id, iter.blk->type,
+					 rsvp->enc_id);
+		iter.blk->rsvp_nxt = rsvp;
+		break;
+	}
+
+	if (!iter.hw) {
+		DPU_ERROR("couldn't reserve cdm for type %d id %d\n", type, id);
+		return -ENAVAIL;
+	}
+
+	return 0;
+}
+
+static int _dpu_rm_reserve_intf(
+		struct dpu_rm *rm,
+		struct dpu_rm_rsvp *rsvp,
+		uint32_t id,
+		enum dpu_hw_blk_type type,
+		bool needs_cdm)
+{
+	struct dpu_rm_hw_iter iter;
+	int ret = 0;
+
+	/* Find the block entry in the rm, and note the reservation */
+	dpu_rm_init_hw_iter(&iter, 0, type);
+	while (_dpu_rm_get_hw_locked(rm, &iter)) {
+		if (iter.blk->id != id)
+			continue;
+
+		if (RESERVED_BY_OTHER(iter.blk, rsvp)) {
+			DPU_ERROR("type %d id %d already reserved\n", type, id);
+			return -ENAVAIL;
+		}
+
+		iter.blk->rsvp_nxt = rsvp;
+		trace_dpu_rm_reserve_intf(iter.blk->id, iter.blk->type,
+					  rsvp->enc_id);
+		break;
+	}
+
+	/* Shouldn't happen since intfs are fixed at probe */
+	if (!iter.hw) {
+		DPU_ERROR("couldn't find type %d id %d\n", type, id);
+		return -EINVAL;
+	}
+
+	if (needs_cdm)
+		ret = _dpu_rm_reserve_cdm(rm, rsvp, id, type);
+
+	return ret;
+}
+
+static int _dpu_rm_reserve_intf_related_hw(
+		struct dpu_rm *rm,
+		struct dpu_rm_rsvp *rsvp,
+		struct dpu_encoder_hw_resources *hw_res)
+{
+	int i, ret = 0;
+	u32 id;
+
+	for (i = 0; i < ARRAY_SIZE(hw_res->intfs); i++) {
+		if (hw_res->intfs[i] == INTF_MODE_NONE)
+			continue;
+		id = i + INTF_0;
+		ret = _dpu_rm_reserve_intf(rm, rsvp, id,
+				DPU_HW_BLK_INTF, hw_res->needs_cdm);
+		if (ret)
+			return ret;
+	}
+
+	return ret;
+}
+
+static int _dpu_rm_make_next_rsvp(
+		struct dpu_rm *rm,
+		struct drm_encoder *enc,
+		struct drm_crtc_state *crtc_state,
+		struct drm_connector_state *conn_state,
+		struct dpu_rm_rsvp *rsvp,
+		struct dpu_rm_requirements *reqs)
+{
+	int ret;
+	struct dpu_rm_topology_def topology;
+
+	/* Create reservation info, tag reserved blocks with it as we go */
+	rsvp->seq = ++rm->rsvp_next_seq;
+	rsvp->enc_id = enc->base.id;
+	rsvp->topology = reqs->topology->top_name;
+	list_add_tail(&rsvp->list, &rm->rsvps);
+
+	ret = _dpu_rm_reserve_lms(rm, rsvp, reqs);
+	if (ret) {
+		DPU_ERROR("unable to find appropriate mixers\n");
+		return ret;
+	}
+
+	/*
+	 * Do assignment preferring to give away low-resource CTLs first:
+	 * - Check mixers without Split Display
+	 * - Only then allow to grab from CTLs with split display capability
+	 */
+	_dpu_rm_reserve_ctls(rm, rsvp, reqs->topology);
+	if (ret && !reqs->topology->needs_split_display) {
+		memcpy(&topology, reqs->topology, sizeof(topology));
+		topology.needs_split_display = true;
+		_dpu_rm_reserve_ctls(rm, rsvp, &topology);
+	}
+	if (ret) {
+		DPU_ERROR("unable to find appropriate CTL\n");
+		return ret;
+	}
+
+	/* Assign INTFs and blks whose usage is tied to them: CTL & CDM */
+	ret = _dpu_rm_reserve_intf_related_hw(rm, rsvp, &reqs->hw_res);
+	if (ret)
+		return ret;
+
+	return ret;
+}
+
+static int _dpu_rm_populate_requirements(
+		struct dpu_rm *rm,
+		struct drm_encoder *enc,
+		struct drm_crtc_state *crtc_state,
+		struct drm_connector_state *conn_state,
+		struct dpu_rm_requirements *reqs,
+		struct msm_display_topology req_topology)
+{
+	int i;
+
+	memset(reqs, 0, sizeof(*reqs));
+
+	dpu_encoder_get_hw_resources(enc, &reqs->hw_res, conn_state);
+
+	for (i = 0; i < DPU_RM_TOPOLOGY_MAX; i++) {
+		if (RM_IS_TOPOLOGY_MATCH(g_top_table[i],
+					req_topology)) {
+			reqs->topology = &g_top_table[i];
+			break;
+		}
+	}
+
+	if (!reqs->topology) {
+		DPU_ERROR("invalid topology for the display\n");
+		return -EINVAL;
+	}
+
+	/**
+	 * Set the requirement based on caps if not set from user space
+	 * This will ensure to select LM tied with DS blocks
+	 * Currently, DS blocks are tied with LM 0 and LM 1 (primary display)
+	 */
+	if (!RM_RQ_DS(reqs) && rm->hw_mdp->caps->has_dest_scaler &&
+		conn_state->connector->connector_type == DRM_MODE_CONNECTOR_DSI)
+		reqs->top_ctrl |= BIT(DPU_RM_TOPCTL_DS);
+
+	DRM_DEBUG_KMS("top_ctrl: 0x%llX num_h_tiles: %d\n", reqs->top_ctrl,
+		      reqs->hw_res.display_num_of_h_tiles);
+	DRM_DEBUG_KMS("num_lm: %d num_ctl: %d topology: %d split_display: %d\n",
+		      reqs->topology->num_lm, reqs->topology->num_ctl,
+		      reqs->topology->top_name,
+		      reqs->topology->needs_split_display);
+
+	return 0;
+}
+
+static struct dpu_rm_rsvp *_dpu_rm_get_rsvp(
+		struct dpu_rm *rm,
+		struct drm_encoder *enc)
+{
+	struct dpu_rm_rsvp *i;
+
+	if (!rm || !enc) {
+		DPU_ERROR("invalid params\n");
+		return NULL;
+	}
+
+	if (list_empty(&rm->rsvps))
+		return NULL;
+
+	list_for_each_entry(i, &rm->rsvps, list)
+		if (i->enc_id == enc->base.id)
+			return i;
+
+	return NULL;
+}
+
+static struct drm_connector *_dpu_rm_get_connector(
+		struct drm_encoder *enc)
+{
+	struct drm_connector *conn = NULL;
+	struct list_head *connector_list =
+			&enc->dev->mode_config.connector_list;
+
+	list_for_each_entry(conn, connector_list, head)
+		if (conn->encoder == enc)
+			return conn;
+
+	return NULL;
+}
+
+/**
+ * _dpu_rm_release_rsvp - release resources and release a reservation
+ * @rm:	KMS handle
+ * @rsvp:	RSVP pointer to release and release resources for
+ */
+static void _dpu_rm_release_rsvp(
+		struct dpu_rm *rm,
+		struct dpu_rm_rsvp *rsvp,
+		struct drm_connector *conn)
+{
+	struct dpu_rm_rsvp *rsvp_c, *rsvp_n;
+	struct dpu_rm_hw_blk *blk;
+	enum dpu_hw_blk_type type;
+
+	if (!rsvp)
+		return;
+
+	DPU_DEBUG("rel rsvp %d enc %d\n", rsvp->seq, rsvp->enc_id);
+
+	list_for_each_entry_safe(rsvp_c, rsvp_n, &rm->rsvps, list) {
+		if (rsvp == rsvp_c) {
+			list_del(&rsvp_c->list);
+			break;
+		}
+	}
+
+	for (type = 0; type < DPU_HW_BLK_MAX; type++) {
+		list_for_each_entry(blk, &rm->hw_blks[type], list) {
+			if (blk->rsvp == rsvp) {
+				blk->rsvp = NULL;
+				DPU_DEBUG("rel rsvp %d enc %d %d %d\n",
+						rsvp->seq, rsvp->enc_id,
+						blk->type, blk->id);
+			}
+			if (blk->rsvp_nxt == rsvp) {
+				blk->rsvp_nxt = NULL;
+				DPU_DEBUG("rel rsvp_nxt %d enc %d %d %d\n",
+						rsvp->seq, rsvp->enc_id,
+						blk->type, blk->id);
+			}
+		}
+	}
+
+	kfree(rsvp);
+}
+
+void dpu_rm_release(struct dpu_rm *rm, struct drm_encoder *enc)
+{
+	struct dpu_rm_rsvp *rsvp;
+	struct drm_connector *conn;
+
+	if (!rm || !enc) {
+		DPU_ERROR("invalid params\n");
+		return;
+	}
+
+	mutex_lock(&rm->rm_lock);
+
+	rsvp = _dpu_rm_get_rsvp(rm, enc);
+	if (!rsvp) {
+		DPU_ERROR("failed to find rsvp for enc %d\n", enc->base.id);
+		goto end;
+	}
+
+	conn = _dpu_rm_get_connector(enc);
+	if (!conn) {
+		DPU_ERROR("failed to get connector for enc %d\n", enc->base.id);
+		goto end;
+	}
+
+	_dpu_rm_release_rsvp(rm, rsvp, conn);
+end:
+	mutex_unlock(&rm->rm_lock);
+}
+
+static int _dpu_rm_commit_rsvp(
+		struct dpu_rm *rm,
+		struct dpu_rm_rsvp *rsvp,
+		struct drm_connector_state *conn_state)
+{
+	struct dpu_rm_hw_blk *blk;
+	enum dpu_hw_blk_type type;
+	int ret = 0;
+
+	/* Swap next rsvp to be the active */
+	for (type = 0; type < DPU_HW_BLK_MAX; type++) {
+		list_for_each_entry(blk, &rm->hw_blks[type], list) {
+			if (blk->rsvp_nxt) {
+				blk->rsvp = blk->rsvp_nxt;
+				blk->rsvp_nxt = NULL;
+			}
+		}
+	}
+
+	if (!ret)
+		DRM_DEBUG_KMS("rsrv enc %d topology %d\n", rsvp->enc_id,
+			      rsvp->topology);
+
+	return ret;
+}
+
+int dpu_rm_reserve(
+		struct dpu_rm *rm,
+		struct drm_encoder *enc,
+		struct drm_crtc_state *crtc_state,
+		struct drm_connector_state *conn_state,
+		struct msm_display_topology topology,
+		bool test_only)
+{
+	struct dpu_rm_rsvp *rsvp_cur, *rsvp_nxt;
+	struct dpu_rm_requirements reqs;
+	int ret;
+
+	if (!rm || !enc || !crtc_state || !conn_state) {
+		DPU_ERROR("invalid arguments\n");
+		return -EINVAL;
+	}
+
+	/* Check if this is just a page-flip */
+	if (!drm_atomic_crtc_needs_modeset(crtc_state))
+		return 0;
+
+	DRM_DEBUG_KMS("reserving hw for conn %d enc %d crtc %d test_only %d\n",
+		      conn_state->connector->base.id, enc->base.id,
+		      crtc_state->crtc->base.id, test_only);
+
+	mutex_lock(&rm->rm_lock);
+
+	_dpu_rm_print_rsvps(rm, DPU_RM_STAGE_BEGIN);
+
+	ret = _dpu_rm_populate_requirements(rm, enc, crtc_state,
+			conn_state, &reqs, topology);
+	if (ret) {
+		DPU_ERROR("failed to populate hw requirements\n");
+		goto end;
+	}
+
+	/*
+	 * We only support one active reservation per-hw-block. But to implement
+	 * transactional semantics for test-only, and for allowing failure while
+	 * modifying your existing reservation, over the course of this
+	 * function we can have two reservations:
+	 * Current: Existing reservation
+	 * Next: Proposed reservation. The proposed reservation may fail, or may
+	 *       be discarded if in test-only mode.
+	 * If reservation is successful, and we're not in test-only, then we
+	 * replace the current with the next.
+	 */
+	rsvp_nxt = kzalloc(sizeof(*rsvp_nxt), GFP_KERNEL);
+	if (!rsvp_nxt) {
+		ret = -ENOMEM;
+		goto end;
+	}
+
+	rsvp_cur = _dpu_rm_get_rsvp(rm, enc);
+
+	/*
+	 * User can request that we clear out any reservation during the
+	 * atomic_check phase by using this CLEAR bit
+	 */
+	if (rsvp_cur && test_only && RM_RQ_CLEAR(&reqs)) {
+		DPU_DEBUG("test_only & CLEAR: clear rsvp[s%de%d]\n",
+				rsvp_cur->seq, rsvp_cur->enc_id);
+		_dpu_rm_release_rsvp(rm, rsvp_cur, conn_state->connector);
+		rsvp_cur = NULL;
+		_dpu_rm_print_rsvps(rm, DPU_RM_STAGE_AFTER_CLEAR);
+	}
+
+	/* Check the proposed reservation, store it in hw's "next" field */
+	ret = _dpu_rm_make_next_rsvp(rm, enc, crtc_state, conn_state,
+			rsvp_nxt, &reqs);
+
+	_dpu_rm_print_rsvps(rm, DPU_RM_STAGE_AFTER_RSVPNEXT);
+
+	if (ret) {
+		DPU_ERROR("failed to reserve hw resources: %d\n", ret);
+		_dpu_rm_release_rsvp(rm, rsvp_nxt, conn_state->connector);
+	} else if (test_only && !RM_RQ_LOCK(&reqs)) {
+		/*
+		 * Normally, if test_only, test the reservation and then undo
+		 * However, if the user requests LOCK, then keep the reservation
+		 * made during the atomic_check phase.
+		 */
+		DPU_DEBUG("test_only: discard test rsvp[s%de%d]\n",
+				rsvp_nxt->seq, rsvp_nxt->enc_id);
+		_dpu_rm_release_rsvp(rm, rsvp_nxt, conn_state->connector);
+	} else {
+		if (test_only && RM_RQ_LOCK(&reqs))
+			DPU_DEBUG("test_only & LOCK: lock rsvp[s%de%d]\n",
+					rsvp_nxt->seq, rsvp_nxt->enc_id);
+
+		_dpu_rm_release_rsvp(rm, rsvp_cur, conn_state->connector);
+
+		ret = _dpu_rm_commit_rsvp(rm, rsvp_nxt, conn_state);
+	}
+
+	_dpu_rm_print_rsvps(rm, DPU_RM_STAGE_FINAL);
+
+end:
+	mutex_unlock(&rm->rm_lock);
+
+	return ret;
+}