1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright 2019 NXP
4 *
5 * Implementation of the SCU IRQ functions using MU.
6 *
7 */
8
9 #include <dt-bindings/firmware/imx/rsrc.h>
10 #include <linux/firmware/imx/ipc.h>
11 #include <linux/firmware/imx/sci.h>
12 #include <linux/mailbox_client.h>
13 #include <linux/suspend.h>
14
15 #define IMX_SC_IRQ_FUNC_ENABLE 1
16 #define IMX_SC_IRQ_FUNC_STATUS 2
17 #define IMX_SC_IRQ_NUM_GROUP 4
18
19 static u32 mu_resource_id;
20
21 struct imx_sc_msg_irq_get_status {
22 struct imx_sc_rpc_msg hdr;
23 union {
24 struct {
25 u16 resource;
26 u8 group;
27 u8 reserved;
28 } __packed req;
29 struct {
30 u32 status;
31 } resp;
32 } data;
33 };
34
35 struct imx_sc_msg_irq_enable {
36 struct imx_sc_rpc_msg hdr;
37 u32 mask;
38 u16 resource;
39 u8 group;
40 u8 enable;
41 } __packed;
42
43 static struct imx_sc_ipc *imx_sc_irq_ipc_handle;
44 static struct work_struct imx_sc_irq_work;
45 static ATOMIC_NOTIFIER_HEAD(imx_scu_irq_notifier_chain);
46
imx_scu_irq_register_notifier(struct notifier_block * nb)47 int imx_scu_irq_register_notifier(struct notifier_block *nb)
48 {
49 return atomic_notifier_chain_register(
50 &imx_scu_irq_notifier_chain, nb);
51 }
52 EXPORT_SYMBOL(imx_scu_irq_register_notifier);
53
imx_scu_irq_unregister_notifier(struct notifier_block * nb)54 int imx_scu_irq_unregister_notifier(struct notifier_block *nb)
55 {
56 return atomic_notifier_chain_unregister(
57 &imx_scu_irq_notifier_chain, nb);
58 }
59 EXPORT_SYMBOL(imx_scu_irq_unregister_notifier);
60
imx_scu_irq_notifier_call_chain(unsigned long status,u8 * group)61 static int imx_scu_irq_notifier_call_chain(unsigned long status, u8 *group)
62 {
63 return atomic_notifier_call_chain(&imx_scu_irq_notifier_chain,
64 status, (void *)group);
65 }
66
imx_scu_irq_work_handler(struct work_struct * work)67 static void imx_scu_irq_work_handler(struct work_struct *work)
68 {
69 struct imx_sc_msg_irq_get_status msg;
70 struct imx_sc_rpc_msg *hdr = &msg.hdr;
71 u32 irq_status;
72 int ret;
73 u8 i;
74
75 for (i = 0; i < IMX_SC_IRQ_NUM_GROUP; i++) {
76 hdr->ver = IMX_SC_RPC_VERSION;
77 hdr->svc = IMX_SC_RPC_SVC_IRQ;
78 hdr->func = IMX_SC_IRQ_FUNC_STATUS;
79 hdr->size = 2;
80
81 msg.data.req.resource = mu_resource_id;
82 msg.data.req.group = i;
83
84 ret = imx_scu_call_rpc(imx_sc_irq_ipc_handle, &msg, true);
85 if (ret) {
86 pr_err("get irq group %d status failed, ret %d\n",
87 i, ret);
88 return;
89 }
90
91 irq_status = msg.data.resp.status;
92 if (!irq_status)
93 continue;
94
95 pm_system_wakeup();
96 imx_scu_irq_notifier_call_chain(irq_status, &i);
97 }
98 }
99
imx_scu_irq_group_enable(u8 group,u32 mask,u8 enable)100 int imx_scu_irq_group_enable(u8 group, u32 mask, u8 enable)
101 {
102 struct imx_sc_msg_irq_enable msg;
103 struct imx_sc_rpc_msg *hdr = &msg.hdr;
104 int ret;
105
106 if (!imx_sc_irq_ipc_handle)
107 return -EPROBE_DEFER;
108
109 hdr->ver = IMX_SC_RPC_VERSION;
110 hdr->svc = IMX_SC_RPC_SVC_IRQ;
111 hdr->func = IMX_SC_IRQ_FUNC_ENABLE;
112 hdr->size = 3;
113
114 msg.resource = mu_resource_id;
115 msg.group = group;
116 msg.mask = mask;
117 msg.enable = enable;
118
119 ret = imx_scu_call_rpc(imx_sc_irq_ipc_handle, &msg, true);
120 if (ret)
121 pr_err("enable irq failed, group %d, mask %d, ret %d\n",
122 group, mask, ret);
123
124 return ret;
125 }
126 EXPORT_SYMBOL(imx_scu_irq_group_enable);
127
imx_scu_irq_callback(struct mbox_client * c,void * msg)128 static void imx_scu_irq_callback(struct mbox_client *c, void *msg)
129 {
130 schedule_work(&imx_sc_irq_work);
131 }
132
imx_scu_enable_general_irq_channel(struct device * dev)133 int imx_scu_enable_general_irq_channel(struct device *dev)
134 {
135 struct of_phandle_args spec;
136 struct mbox_client *cl;
137 struct mbox_chan *ch;
138 int ret = 0, i = 0;
139
140 ret = imx_scu_get_handle(&imx_sc_irq_ipc_handle);
141 if (ret)
142 return ret;
143
144 cl = devm_kzalloc(dev, sizeof(*cl), GFP_KERNEL);
145 if (!cl)
146 return -ENOMEM;
147
148 cl->dev = dev;
149 cl->rx_callback = imx_scu_irq_callback;
150
151 /* SCU general IRQ uses general interrupt channel 3 */
152 ch = mbox_request_channel_byname(cl, "gip3");
153 if (IS_ERR(ch)) {
154 ret = PTR_ERR(ch);
155 dev_err(dev, "failed to request mbox chan gip3, ret %d\n", ret);
156 devm_kfree(dev, cl);
157 return ret;
158 }
159
160 INIT_WORK(&imx_sc_irq_work, imx_scu_irq_work_handler);
161
162 if (!of_parse_phandle_with_args(dev->of_node, "mboxes",
163 "#mbox-cells", 0, &spec))
164 i = of_alias_get_id(spec.np, "mu");
165
166 /* use mu1 as general mu irq channel if failed */
167 if (i < 0)
168 i = 1;
169
170 mu_resource_id = IMX_SC_R_MU_0A + i;
171
172 return ret;
173 }
174 EXPORT_SYMBOL(imx_scu_enable_general_irq_channel);
175