xref: /openbmc/u-boot/arch/x86/cpu/ivybridge/early_me.c (revision ae485b54)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * From Coreboot src/southbridge/intel/bd82x6x/early_me.c
4  *
5  * Copyright (C) 2011 The Chromium OS Authors. All rights reserved.
6  */
7 
8 #include <common.h>
9 #include <dm.h>
10 #include <errno.h>
11 #include <asm/pci.h>
12 #include <asm/cpu.h>
13 #include <asm/processor.h>
14 #include <asm/arch/me.h>
15 #include <asm/arch/pch.h>
16 #include <asm/io.h>
17 
18 static const char *const me_ack_values[] = {
19 	[ME_HFS_ACK_NO_DID]	= "No DID Ack received",
20 	[ME_HFS_ACK_RESET]	= "Non-power cycle reset",
21 	[ME_HFS_ACK_PWR_CYCLE]	= "Power cycle reset",
22 	[ME_HFS_ACK_S3]		= "Go to S3",
23 	[ME_HFS_ACK_S4]		= "Go to S4",
24 	[ME_HFS_ACK_S5]		= "Go to S5",
25 	[ME_HFS_ACK_GBL_RESET]	= "Global Reset",
26 	[ME_HFS_ACK_CONTINUE]	= "Continue to boot"
27 };
28 
29 int intel_early_me_init(struct udevice *me_dev)
30 {
31 	int count;
32 	struct me_uma uma;
33 	struct me_hfs hfs;
34 
35 	debug("Intel ME early init\n");
36 
37 	/* Wait for ME UMA SIZE VALID bit to be set */
38 	for (count = ME_RETRY; count > 0; --count) {
39 		pci_read_dword_ptr(me_dev, &uma, PCI_ME_UMA);
40 		if (uma.valid)
41 			break;
42 		udelay(ME_DELAY);
43 	}
44 	if (!count) {
45 		printf("ERROR: ME is not ready!\n");
46 		return -EBUSY;
47 	}
48 
49 	/* Check for valid firmware */
50 	pci_read_dword_ptr(me_dev, &hfs, PCI_ME_HFS);
51 	if (hfs.fpt_bad) {
52 		printf("WARNING: ME has bad firmware\n");
53 		return -EBADF;
54 	}
55 
56 	debug("Intel ME firmware is ready\n");
57 
58 	return 0;
59 }
60 
61 int intel_early_me_uma_size(struct udevice *me_dev)
62 {
63 	struct me_uma uma;
64 
65 	pci_read_dword_ptr(me_dev, &uma, PCI_ME_UMA);
66 	if (uma.valid) {
67 		debug("ME: Requested %uMB UMA\n", uma.size);
68 		return uma.size;
69 	}
70 
71 	debug("ME: Invalid UMA size\n");
72 	return -EINVAL;
73 }
74 
75 static inline void set_global_reset(struct udevice *dev, int enable)
76 {
77 	u32 etr3;
78 
79 	dm_pci_read_config32(dev, ETR3, &etr3);
80 
81 	/* Clear CF9 Without Resume Well Reset Enable */
82 	etr3 &= ~ETR3_CWORWRE;
83 
84 	/* CF9GR indicates a Global Reset */
85 	if (enable)
86 		etr3 |= ETR3_CF9GR;
87 	else
88 		etr3 &= ~ETR3_CF9GR;
89 
90 	dm_pci_write_config32(dev, ETR3, etr3);
91 }
92 
93 int intel_early_me_init_done(struct udevice *dev, struct udevice *me_dev,
94 			     uint status)
95 {
96 	int count;
97 	u32 mebase_l, mebase_h;
98 	struct me_hfs hfs;
99 	struct me_did did = {
100 		.init_done = ME_INIT_DONE,
101 		.status = status
102 	};
103 
104 	/* MEBASE from MESEG_BASE[35:20] */
105 	dm_pci_read_config32(PCH_DEV, PCI_CPU_MEBASE_L, &mebase_l);
106 	dm_pci_read_config32(PCH_DEV, PCI_CPU_MEBASE_H, &mebase_h);
107 	mebase_h &= 0xf;
108 	did.uma_base = (mebase_l >> 20) | (mebase_h << 12);
109 
110 	/* Send message to ME */
111 	debug("ME: Sending Init Done with status: %d, UMA base: 0x%04x\n",
112 	      status, did.uma_base);
113 
114 	pci_write_dword_ptr(me_dev, &did, PCI_ME_H_GS);
115 
116 	/* Must wait for ME acknowledgement */
117 	for (count = ME_RETRY; count > 0; --count) {
118 		pci_read_dword_ptr(me_dev, &hfs, PCI_ME_HFS);
119 		if (hfs.bios_msg_ack)
120 			break;
121 		udelay(ME_DELAY);
122 	}
123 	if (!count) {
124 		printf("ERROR: ME failed to respond\n");
125 		return -ETIMEDOUT;
126 	}
127 
128 	/* Return the requested BIOS action */
129 	debug("ME: Requested BIOS Action: %s\n", me_ack_values[hfs.ack_data]);
130 
131 	/* Check status after acknowledgement */
132 	intel_me_status(me_dev);
133 
134 	switch (hfs.ack_data) {
135 	case ME_HFS_ACK_CONTINUE:
136 		/* Continue to boot */
137 		return 0;
138 	case ME_HFS_ACK_RESET:
139 		/* Non-power cycle reset */
140 		set_global_reset(dev, 0);
141 		reset_cpu(0);
142 		break;
143 	case ME_HFS_ACK_PWR_CYCLE:
144 		/* Power cycle reset */
145 		set_global_reset(dev, 0);
146 		x86_full_reset();
147 		break;
148 	case ME_HFS_ACK_GBL_RESET:
149 		/* Global reset */
150 		set_global_reset(dev, 1);
151 		x86_full_reset();
152 		break;
153 	case ME_HFS_ACK_S3:
154 	case ME_HFS_ACK_S4:
155 	case ME_HFS_ACK_S5:
156 		break;
157 	}
158 
159 	return -EINVAL;
160 }
161 
162 static const struct udevice_id ivybridge_syscon_ids[] = {
163 	{ .compatible = "intel,me", .data = X86_SYSCON_ME },
164 	{ }
165 };
166 
167 U_BOOT_DRIVER(syscon_intel_me) = {
168 	.name = "intel_me_syscon",
169 	.id = UCLASS_SYSCON,
170 	.of_match = ivybridge_syscon_ids,
171 };
172