1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Microchip's PolarFire SoC (MPFS) System Controller Driver
4  *
5  * Copyright (C) 2024 Microchip Technology Inc. All rights reserved.
6  *
7  * Author: Jamie Gibbons <jamie.gibbons@microchip.com>
8  *
9  */
10 
11 #include <asm/system.h>
12 #include <dm.h>
13 #include <dm/device_compat.h>
14 #include <env.h>
15 #include <errno.h>
16 #include <linux/compat.h>
17 #include <linux/completion.h>
18 #include <linux/err.h>
19 #include <linux/mtd/mtd.h>
20 #include <log.h>
21 #include <mailbox.h>
22 #include <misc.h>
23 #include <mpfs-mailbox.h>
24 
25 /* Descriptor table */
26 #define CMD_OPCODE						0x0u
27 #define CMD_DATA_SIZE					0U
28 #define CMD_DATA						NULL
29 #define MBOX_OFFSET						0x0
30 #define RESP_OFFSET						0x0
31 #define RESP_BYTES						16U
32 
33 /**
34  * struct mpfs_syscontroller_priv - Structure representing System Controller data.
35  * @chan:	Mailbox channel
36  * @c:	Completion signal
37  */
38 struct mpfs_syscontroller_priv {
39 	struct mbox_chan chan;
40 	struct completion c;
41 };
42 
43 /**
44  * mpfs_syscontroller_run_service() - Run the MPFS system service
45  * @sys_controller:	corresponding MPFS system service device
46  * @msg:	Message to send
47  *
48  * Return: 0 if all goes good, else appropriate error message.
49  */
mpfs_syscontroller_run_service(struct mpfs_syscontroller_priv * sys_controller,struct mpfs_mss_msg * msg)50 int mpfs_syscontroller_run_service(struct mpfs_syscontroller_priv *sys_controller, struct mpfs_mss_msg *msg)
51 {
52 	int ret;
53 
54 	reinit_completion(&sys_controller->c);
55 
56 	/* Run the System Service Request */
57 	ret = mbox_send(&sys_controller->chan, msg);
58 	if (ret < 0)
59 		dev_warn(sys_controller->chan.dev, "MPFS sys controller service timeout\n");
60 
61 	debug("%s: Service successful %s\n",
62 	      __func__, sys_controller->chan.dev->name);
63 
64 	return ret;
65 }
66 EXPORT_SYMBOL_GPL(mpfs_syscontroller_run_service);
67 
68 /**
69  * mpfs_syscontroller_read_sernum() - Use system service to read the device serial number
70  * @sys_serv_priv:	system service private data
71  * @device_serial_number:	device serial number
72  *
73  * Return: 0 if all went ok, else return appropriate error
74  */
mpfs_syscontroller_read_sernum(struct mpfs_sys_serv * sys_serv_priv,u8 * device_serial_number)75 int mpfs_syscontroller_read_sernum(struct mpfs_sys_serv *sys_serv_priv, u8 *device_serial_number)
76 {
77 	unsigned long timeoutsecs = 300;
78 	int ret;
79 
80 	struct mpfs_mss_response response = {
81 		.resp_status = 0U,
82 		.resp_msg = (u32 *)device_serial_number,
83 		.resp_size = RESP_BYTES};
84 	struct mpfs_mss_msg msg = {
85 		.cmd_opcode = CMD_OPCODE,
86 		.cmd_data_size = CMD_DATA_SIZE,
87 		.response = &response,
88 		.cmd_data = CMD_DATA,
89 		.mbox_offset = MBOX_OFFSET,
90 		.resp_offset = RESP_OFFSET};
91 
92 	ret = mpfs_syscontroller_run_service(sys_serv_priv->sys_controller, &msg);
93 	if (ret) {
94 		dev_err(sys_serv_priv->sys_controller->chan.dev, "Service failed: %d, abort\n", ret);
95 		return ret;
96 	}
97 
98 	/* Receive the response */
99 	ret = mbox_recv(&sys_serv_priv->sys_controller->chan, &msg, timeoutsecs);
100 	if (ret) {
101 		dev_err(sys_serv_priv->sys_controller->chan.dev, "Service failed: %d, abort. Failure: %u\n", ret, msg.response->resp_status);
102 		return ret;
103 	}
104 
105 	debug("%s: Read successful %s\n",
106 	      __func__, sys_serv_priv->sys_controller->chan.dev->name);
107 
108 	return 0;
109 }
110 EXPORT_SYMBOL(mpfs_syscontroller_read_sernum);
111 
mpfs_syscontroller_probe(struct udevice * dev)112 static int mpfs_syscontroller_probe(struct udevice *dev)
113 {
114 	struct mpfs_syscontroller_priv *sys_controller = dev_get_priv(dev);
115 	int ret;
116 
117 	ret = mbox_get_by_index(dev, 0, &sys_controller->chan);
118 	if (ret) {
119 		dev_err(dev, "%s: Acquiring mailbox channel failed. ret = %d\n",
120 			__func__, ret);
121 		return ret;
122 	}
123 
124 	init_completion(&sys_controller->c);
125 	dev_info(dev, "Registered MPFS system controller\n");
126 
127 	return 0;
128 }
129 
130 static const struct udevice_id mpfs_syscontroller_ids[] = {
131 	{ .compatible = "microchip,mpfs-sys-controller" },
132 	{ }
133 };
134 
mpfs_syscontroller_get(struct udevice * dev)135 struct mpfs_syscontroller_priv *mpfs_syscontroller_get(struct udevice *dev)
136 {
137 	struct mpfs_syscontroller_priv *sys_controller;
138 
139 	sys_controller = dev_get_priv(dev);
140 	if (!sys_controller) {
141 		debug("%s: MPFS system controller found but could not register as a sub device %p\n",
142 		      __func__, sys_controller);
143 		return ERR_PTR(-EPROBE_DEFER);
144 	}
145 
146 	return sys_controller;
147 }
148 EXPORT_SYMBOL(mpfs_syscontroller_get);
149 
150 U_BOOT_DRIVER(mpfs_syscontroller) = {
151 	.name           = "mpfs_syscontroller",
152 	.id             = UCLASS_MISC,
153 	.of_match       = mpfs_syscontroller_ids,
154 	.probe          = mpfs_syscontroller_probe,
155 	.priv_auto	= sizeof(struct mpfs_syscontroller_priv),
156 };
157