1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2017-2018, The Linux Foundation. All rights reserved.
5 #define pr_fmt(fmt) "[drm:%s:%d] " fmt, __func__, __LINE__
7 #include <linux/mutex.h>
8 #include <linux/errno.h>
9 #include <linux/slab.h>
11 #include "dpu_hw_mdss.h"
12 #include "dpu_hw_blk.h"
14 /* Serialization lock for dpu_hw_blk_list */
15 static DEFINE_MUTEX(dpu_hw_blk_lock);
17 /* List of all hw block objects */
18 static LIST_HEAD(dpu_hw_blk_list);
21 * dpu_hw_blk_init - initialize hw block object
22 * @hw_blk: pointer to hw block object
23 * @type: hw block type - enum dpu_hw_blk_type
24 * @id: instance id of the hw block
25 * @ops: Pointer to block operations
27 void dpu_hw_blk_init(struct dpu_hw_blk *hw_blk, u32 type, int id,
28 struct dpu_hw_blk_ops *ops)
30 INIT_LIST_HEAD(&hw_blk->list);
33 atomic_set(&hw_blk->refcount, 0);
38 mutex_lock(&dpu_hw_blk_lock);
39 list_add(&hw_blk->list, &dpu_hw_blk_list);
40 mutex_unlock(&dpu_hw_blk_lock);
44 * dpu_hw_blk_destroy - destroy hw block object.
45 * @hw_blk: pointer to hw block object
48 void dpu_hw_blk_destroy(struct dpu_hw_blk *hw_blk)
51 pr_err("invalid parameters\n");
55 if (atomic_read(&hw_blk->refcount))
56 pr_err("hw_blk:%d.%d invalid refcount\n", hw_blk->type,
59 mutex_lock(&dpu_hw_blk_lock);
60 list_del(&hw_blk->list);
61 mutex_unlock(&dpu_hw_blk_lock);
65 * dpu_hw_blk_get - get hw_blk from free pool
66 * @hw_blk: if specified, increment reference count only
67 * @type: if hw_blk is not specified, allocate the next available of this type
68 * @id: if specified (>= 0), allocate the given instance of the above type
69 * return: pointer to hw block object
71 struct dpu_hw_blk *dpu_hw_blk_get(struct dpu_hw_blk *hw_blk, u32 type, int id)
73 struct dpu_hw_blk *curr;
77 mutex_lock(&dpu_hw_blk_lock);
78 list_for_each_entry(curr, &dpu_hw_blk_list, list) {
79 if ((curr->type != type) ||
80 (id >= 0 && curr->id != id) ||
82 atomic_read(&curr->refcount)))
88 mutex_unlock(&dpu_hw_blk_lock);
92 pr_debug("no hw_blk:%d\n", type);
96 refcount = atomic_inc_return(&hw_blk->refcount);
98 if (refcount == 1 && hw_blk->ops.start) {
99 rc = hw_blk->ops.start(hw_blk);
101 pr_err("failed to start hw_blk:%d rc:%d\n", type, rc);
106 pr_debug("hw_blk:%d.%d refcount:%d\n", hw_blk->type,
107 hw_blk->id, refcount);
111 dpu_hw_blk_put(hw_blk);
116 * dpu_hw_blk_put - put hw_blk to free pool if decremented refcount is zero
117 * @hw_blk: hw block to be freed
119 void dpu_hw_blk_put(struct dpu_hw_blk *hw_blk)
122 pr_err("invalid parameters\n");
126 pr_debug("hw_blk:%d.%d refcount:%d\n", hw_blk->type, hw_blk->id,
127 atomic_read(&hw_blk->refcount));
129 if (!atomic_read(&hw_blk->refcount)) {
130 pr_err("hw_blk:%d.%d invalid put\n", hw_blk->type, hw_blk->id);
134 if (atomic_dec_return(&hw_blk->refcount))
137 if (hw_blk->ops.stop)
138 hw_blk->ops.stop(hw_blk);