1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright 2018 NXP
4  *
5  * Peng Fan <peng.fan@nxp.com>
6  */
7 
8 #include <common.h>
9 #include <log.h>
10 #include <asm/global_data.h>
11 #include <asm/io.h>
12 #include <dm.h>
13 #include <dm/lists.h>
14 #include <dm/root.h>
15 #include <dm/device-internal.h>
16 #include <asm/arch/sci/sci.h>
17 #include <linux/bitops.h>
18 #include <linux/iopoll.h>
19 #include <misc.h>
20 
21 DECLARE_GLOBAL_DATA_PTR;
22 
23 struct mu_type {
24 	u32 tr[4];
25 	u32 rr[4];
26 	u32 sr;
27 	u32 cr;
28 };
29 
30 struct imx8_scu {
31 	struct mu_type *base;
32 };
33 
34 #define MU_CR_GIE_MASK		0xF0000000u
35 #define MU_CR_RIE_MASK		0xF000000u
36 #define MU_CR_GIR_MASK		0xF0000u
37 #define MU_CR_TIE_MASK		0xF00000u
38 #define MU_CR_F_MASK		0x7u
39 #define MU_SR_TE0_MASK		BIT(23)
40 #define MU_SR_RF0_MASK		BIT(27)
41 #define MU_TR_COUNT		4
42 #define MU_RR_COUNT		4
43 
mu_hal_init(struct mu_type * base)44 static inline void mu_hal_init(struct mu_type *base)
45 {
46 	/* Clear GIEn, RIEn, TIEn, GIRn and ABFn. */
47 	clrbits_le32(&base->cr, MU_CR_GIE_MASK | MU_CR_RIE_MASK |
48 		     MU_CR_TIE_MASK | MU_CR_GIR_MASK | MU_CR_F_MASK);
49 }
50 
mu_hal_sendmsg(struct mu_type * base,u32 reg_index,u32 msg)51 static int mu_hal_sendmsg(struct mu_type *base, u32 reg_index, u32 msg)
52 {
53 	u32 mask = MU_SR_TE0_MASK >> reg_index;
54 	u32 val;
55 	int ret;
56 
57 	assert(reg_index < MU_TR_COUNT);
58 
59 	/* Wait TX register to be empty. */
60 	ret = readl_poll_timeout(&base->sr, val, val & mask, 10000);
61 	if (ret < 0) {
62 		printf("%s timeout\n", __func__);
63 		return -ETIMEDOUT;
64 	}
65 
66 	writel(msg, &base->tr[reg_index]);
67 
68 	return 0;
69 }
70 
mu_hal_receivemsg(struct mu_type * base,u32 reg_index,u32 * msg)71 static int mu_hal_receivemsg(struct mu_type *base, u32 reg_index, u32 *msg)
72 {
73 	u32 mask = MU_SR_RF0_MASK >> reg_index;
74 	u32 val;
75 	int ret;
76 
77 	assert(reg_index < MU_TR_COUNT);
78 
79 	/* Wait RX register to be full. */
80 	ret = readl_poll_timeout(&base->sr, val, val & mask, 1000000);
81 	if (ret < 0) {
82 		printf("%s timeout\n", __func__);
83 		return -ETIMEDOUT;
84 	}
85 
86 	*msg = readl(&base->rr[reg_index]);
87 
88 	return 0;
89 }
90 
sc_ipc_read(struct mu_type * base,void * data)91 static int sc_ipc_read(struct mu_type *base, void *data)
92 {
93 	struct sc_rpc_msg_s *msg = (struct sc_rpc_msg_s *)data;
94 	int ret;
95 	u8 count = 0;
96 
97 	if (!msg)
98 		return -EINVAL;
99 
100 	/* Read first word */
101 	ret = mu_hal_receivemsg(base, 0, (u32 *)msg);
102 	if (ret)
103 		return ret;
104 	count++;
105 
106 	/* Check size */
107 	if (msg->size > SC_RPC_MAX_MSG) {
108 		*((u32 *)msg) = 0;
109 		return -EINVAL;
110 	}
111 
112 	/* Read remaining words */
113 	while (count < msg->size) {
114 		ret = mu_hal_receivemsg(base, count % MU_RR_COUNT,
115 					&msg->DATA.u32[count - 1]);
116 		if (ret)
117 			return ret;
118 		count++;
119 	}
120 
121 	return 0;
122 }
123 
sc_ipc_write(struct mu_type * base,void * data)124 static int sc_ipc_write(struct mu_type *base, void *data)
125 {
126 	struct sc_rpc_msg_s *msg = (struct sc_rpc_msg_s *)data;
127 	int ret;
128 	u8 count = 0;
129 
130 	if (!msg)
131 		return -EINVAL;
132 
133 	/* Check size */
134 	if (msg->size > SC_RPC_MAX_MSG)
135 		return -EINVAL;
136 
137 	/* Write first word */
138 	ret = mu_hal_sendmsg(base, 0, *((u32 *)msg));
139 	if (ret)
140 		return ret;
141 	count++;
142 
143 	/* Write remaining words */
144 	while (count < msg->size) {
145 		ret = mu_hal_sendmsg(base, count % MU_TR_COUNT,
146 				     msg->DATA.u32[count - 1]);
147 		if (ret)
148 			return ret;
149 		count++;
150 	}
151 
152 	return 0;
153 }
154 
155 /*
156  * Note the function prototype use msgid as the 2nd parameter, here
157  * we take it as no_resp.
158  */
imx8_scu_call(struct udevice * dev,int no_resp,void * tx_msg,int tx_size,void * rx_msg,int rx_size)159 static int imx8_scu_call(struct udevice *dev, int no_resp, void *tx_msg,
160 			 int tx_size, void *rx_msg, int rx_size)
161 {
162 	struct imx8_scu *plat = dev_get_plat(dev);
163 	sc_err_t result;
164 	int ret;
165 
166 	/* Expect tx_msg, rx_msg are the same value */
167 	if (rx_msg && tx_msg != rx_msg)
168 		printf("tx_msg %p, rx_msg %p\n", tx_msg, rx_msg);
169 
170 	ret = sc_ipc_write(plat->base, tx_msg);
171 	if (ret)
172 		return ret;
173 	if (!no_resp) {
174 		ret = sc_ipc_read(plat->base, rx_msg);
175 		if (ret)
176 			return ret;
177 	}
178 
179 	result = RPC_R8((struct sc_rpc_msg_s *)tx_msg);
180 
181 	return sc_err_to_linux(result);
182 }
183 
imx8_scu_probe(struct udevice * dev)184 static int imx8_scu_probe(struct udevice *dev)
185 {
186 	struct imx8_scu *plat = dev_get_plat(dev);
187 	fdt_addr_t addr;
188 
189 	debug("%s(dev=%p) (plat=%p)\n", __func__, dev, plat);
190 
191 	addr = dev_read_addr(dev);
192 	if (addr == FDT_ADDR_T_NONE)
193 		return -EINVAL;
194 
195 #ifdef CONFIG_SPL_BUILD
196 	plat->base = (struct mu_type *)CONFIG_MU_BASE_SPL;
197 #else
198 	plat->base = (struct mu_type *)addr;
199 #endif
200 
201 	/* U-Boot not enable interrupts, so need to enable RX interrupts */
202 	mu_hal_init(plat->base);
203 
204 	gd->arch.scu_dev = dev;
205 
206 	return 0;
207 }
208 
imx8_scu_remove(struct udevice * dev)209 static int imx8_scu_remove(struct udevice *dev)
210 {
211 	return 0;
212 }
213 
imx8_scu_bind(struct udevice * dev)214 static int imx8_scu_bind(struct udevice *dev)
215 {
216 	int ret;
217 	struct udevice *child;
218 	ofnode node;
219 
220 	debug("%s(dev=%p)\n", __func__, dev);
221 	ofnode_for_each_subnode(node, dev_ofnode(dev)) {
222 		ret = lists_bind_fdt(dev, node, &child, true);
223 		if (ret)
224 			return ret;
225 		debug("bind child dev %s\n", child->name);
226 	}
227 
228 	return 0;
229 }
230 
231 static struct misc_ops imx8_scu_ops = {
232 	.call = imx8_scu_call,
233 };
234 
235 static const struct udevice_id imx8_scu_ids[] = {
236 	{ .compatible = "fsl,imx8qxp-mu" },
237 	{ .compatible = "fsl,imx8-mu" },
238 	{ }
239 };
240 
241 U_BOOT_DRIVER(imx8_scu) = {
242 	.name		= "imx8_scu",
243 	.id		= UCLASS_MISC,
244 	.of_match	= imx8_scu_ids,
245 	.probe		= imx8_scu_probe,
246 	.bind		= imx8_scu_bind,
247 	.remove		= imx8_scu_remove,
248 	.ops		= &imx8_scu_ops,
249 	.plat_auto	= sizeof(struct imx8_scu),
250 	.flags		= DM_FLAG_PRE_RELOC,
251 };
252