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