1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * OMAP IOMMU quirks for various TI SoCs
4 *
5 * Copyright (C) 2015-2019 Texas Instruments Incorporated - https://www.ti.com/
6 * Suman Anna <s-anna@ti.com>
7 */
8
9 #include <linux/platform_device.h>
10 #include <linux/err.h>
11 #include <linux/clk.h>
12 #include <linux/list.h>
13
14 #include "clockdomain.h"
15 #include "powerdomain.h"
16 #include "common.h"
17
18 struct pwrdm_link {
19 struct device *dev;
20 struct powerdomain *pwrdm;
21 struct list_head node;
22 };
23
24 static DEFINE_SPINLOCK(iommu_lock);
25 static struct clockdomain *emu_clkdm;
26 static atomic_t emu_count;
27
28 static void omap_iommu_dra7_emu_swsup_config(struct platform_device *pdev,
29 bool enable)
30 {
31 struct device_node *np = pdev->dev.of_node;
32 unsigned long flags;
33
34 if (!of_device_is_compatible(np, "ti,dra7-dsp-iommu"))
35 return;
36
37 if (!emu_clkdm) {
38 emu_clkdm = clkdm_lookup("emu_clkdm");
39 if (WARN_ON_ONCE(!emu_clkdm))
40 return;
41 }
42
43 spin_lock_irqsave(&iommu_lock, flags);
44
45 if (enable && (atomic_inc_return(&emu_count) == 1))
46 clkdm_deny_idle(emu_clkdm);
47 else if (!enable && (atomic_dec_return(&emu_count) == 0))
48 clkdm_allow_idle(emu_clkdm);
49
50 spin_unlock_irqrestore(&iommu_lock, flags);
51 }
52
53 static struct powerdomain *_get_pwrdm(struct device *dev)
54 {
55 struct clk *clk;
56 struct clk_hw_omap *hwclk;
57 struct clockdomain *clkdm;
58 struct powerdomain *pwrdm = NULL;
59 struct pwrdm_link *entry;
60 unsigned long flags;
61 static LIST_HEAD(cache);
62
63 spin_lock_irqsave(&iommu_lock, flags);
64
65 list_for_each_entry(entry, &cache, node) {
66 if (entry->dev == dev) {
67 pwrdm = entry->pwrdm;
68 break;
69 }
70 }
71
72 spin_unlock_irqrestore(&iommu_lock, flags);
73
74 if (pwrdm)
75 return pwrdm;
76
77 clk = of_clk_get(dev->of_node->parent, 0);
78 if (IS_ERR(clk)) {
79 dev_err(dev, "no fck found\n");
80 return NULL;
81 }
82
83 hwclk = to_clk_hw_omap(__clk_get_hw(clk));
84 clk_put(clk);
85 if (!hwclk || !hwclk->clkdm_name) {
86 dev_err(dev, "no hwclk data\n");
87 return NULL;
88 }
89
90 clkdm = clkdm_lookup(hwclk->clkdm_name);
91 if (!clkdm) {
92 dev_err(dev, "clkdm not found: %s\n", hwclk->clkdm_name);
93 return NULL;
94 }
95
96 pwrdm = clkdm_get_pwrdm(clkdm);
97 if (!pwrdm) {
98 dev_err(dev, "pwrdm not found: %s\n", clkdm->name);
99 return NULL;
100 }
101
102 entry = kmalloc(sizeof(*entry), GFP_KERNEL);
103 if (entry) {
104 entry->dev = dev;
105 entry->pwrdm = pwrdm;
106 spin_lock_irqsave(&iommu_lock, flags);
107 list_add(&entry->node, &cache);
108 spin_unlock_irqrestore(&iommu_lock, flags);
109 }
110
111 return pwrdm;
112 }
113
114 int omap_iommu_set_pwrdm_constraint(struct platform_device *pdev, bool request,
115 u8 *pwrst)
116 {
117 struct powerdomain *pwrdm;
118 u8 next_pwrst;
119 int ret = 0;
120
121 pwrdm = _get_pwrdm(&pdev->dev);
122 if (!pwrdm)
123 return -ENODEV;
124
125 if (request) {
126 *pwrst = pwrdm_read_next_pwrst(pwrdm);
127 omap_iommu_dra7_emu_swsup_config(pdev, true);
128 }
129
130 if (*pwrst > PWRDM_POWER_RET)
131 goto out;
132
133 next_pwrst = request ? PWRDM_POWER_ON : *pwrst;
134
135 ret = pwrdm_set_next_pwrst(pwrdm, next_pwrst);
136
137 out:
138 if (!request)
139 omap_iommu_dra7_emu_swsup_config(pdev, false);
140
141 return ret;
142 }
143
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