xref: /openbmc/linux/arch/mips/ralink/mt7621.c (revision cabce92d)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *
4  * Copyright (C) 2015 Nikolay Martynov <mar.kolya@gmail.com>
5  * Copyright (C) 2015 John Crispin <john@phrozen.org>
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/init.h>
10 #include <linux/slab.h>
11 #include <linux/sys_soc.h>
12 #include <linux/memblock.h>
13 #include <linux/pci.h>
14 #include <linux/bug.h>
15 
16 #include <asm/bootinfo.h>
17 #include <asm/mipsregs.h>
18 #include <asm/smp-ops.h>
19 #include <asm/mips-cps.h>
20 #include <asm/mach-ralink/ralink_regs.h>
21 #include <asm/mach-ralink/mt7621.h>
22 
23 #include "common.h"
24 
25 #define MT7621_MEM_TEST_PATTERN         0xaa5555aa
26 
27 static u32 detect_magic __initdata;
28 static struct ralink_soc_info *soc_info_ptr;
29 
30 int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
31 {
32 	struct resource_entry *entry;
33 	resource_size_t mask;
34 
35 	entry = resource_list_first_type(&bridge->windows, IORESOURCE_MEM);
36 	if (!entry) {
37 		pr_err("Cannot get memory resource\n");
38 		return -EINVAL;
39 	}
40 
41 	if (mips_cps_numiocu(0)) {
42 		/*
43 		 * Hardware doesn't accept mask values with 1s after
44 		 * 0s (e.g. 0xffef), so warn if that's happen
45 		 */
46 		mask = ~(entry->res->end - entry->res->start) & CM_GCR_REGn_MASK_ADDRMASK;
47 		WARN_ON(mask && BIT(ffz(~mask)) - 1 != ~mask);
48 
49 		write_gcr_reg1_base(entry->res->start);
50 		write_gcr_reg1_mask(mask | CM_GCR_REGn_MASK_CMTGT_IOCU0);
51 		pr_info("PCI coherence region base: 0x%08llx, mask/settings: 0x%08llx\n",
52 			(unsigned long long)read_gcr_reg1_base(),
53 			(unsigned long long)read_gcr_reg1_mask());
54 	}
55 
56 	return 0;
57 }
58 
59 phys_addr_t mips_cpc_default_phys_base(void)
60 {
61 	panic("Cannot detect cpc address");
62 }
63 
64 static bool __init mt7621_addr_wraparound_test(phys_addr_t size)
65 {
66 	void *dm = (void *)KSEG1ADDR(&detect_magic);
67 
68 	if (CPHYSADDR(dm + size) >= MT7621_LOWMEM_MAX_SIZE)
69 		return true;
70 	__raw_writel(MT7621_MEM_TEST_PATTERN, dm);
71 	if (__raw_readl(dm) != __raw_readl(dm + size))
72 		return false;
73 	__raw_writel(~MT7621_MEM_TEST_PATTERN, dm);
74 	return __raw_readl(dm) == __raw_readl(dm + size);
75 }
76 
77 static void __init mt7621_memory_detect(void)
78 {
79 	phys_addr_t size;
80 
81 	for (size = 32 * SZ_1M; size <= 256 * SZ_1M; size <<= 1) {
82 		if (mt7621_addr_wraparound_test(size)) {
83 			memblock_add(MT7621_LOWMEM_BASE, size);
84 			return;
85 		}
86 	}
87 
88 	memblock_add(MT7621_LOWMEM_BASE, MT7621_LOWMEM_MAX_SIZE);
89 	memblock_add(MT7621_HIGHMEM_BASE, MT7621_HIGHMEM_SIZE);
90 }
91 
92 static unsigned int __init mt7621_get_soc_name0(void)
93 {
94 	return __raw_readl(MT7621_SYSC_BASE + SYSC_REG_CHIP_NAME0);
95 }
96 
97 static unsigned int __init mt7621_get_soc_name1(void)
98 {
99 	return __raw_readl(MT7621_SYSC_BASE + SYSC_REG_CHIP_NAME1);
100 }
101 
102 static bool __init mt7621_soc_valid(void)
103 {
104 	if (mt7621_get_soc_name0() == MT7621_CHIP_NAME0 &&
105 			mt7621_get_soc_name1() == MT7621_CHIP_NAME1)
106 		return true;
107 	else
108 		return false;
109 }
110 
111 static const char __init *mt7621_get_soc_id(void)
112 {
113 	if (mt7621_soc_valid())
114 		return "MT7621";
115 	else
116 		return "invalid";
117 }
118 
119 static unsigned int __init mt7621_get_soc_rev(void)
120 {
121 	return __raw_readl(MT7621_SYSC_BASE + SYSC_REG_CHIP_REV);
122 }
123 
124 static unsigned int __init mt7621_get_soc_ver(void)
125 {
126 	return (mt7621_get_soc_rev() >> CHIP_REV_VER_SHIFT) & CHIP_REV_VER_MASK;
127 }
128 
129 static unsigned int __init mt7621_get_soc_eco(void)
130 {
131 	return (mt7621_get_soc_rev() & CHIP_REV_ECO_MASK);
132 }
133 
134 static const char __init *mt7621_get_soc_revision(void)
135 {
136 	if (mt7621_get_soc_rev() == 1 && mt7621_get_soc_eco() == 1)
137 		return "E2";
138 	else
139 		return "E1";
140 }
141 
142 static int __init mt7621_soc_dev_init(void)
143 {
144 	struct soc_device *soc_dev;
145 	struct soc_device_attribute *soc_dev_attr;
146 
147 	soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
148 	if (!soc_dev_attr)
149 		return -ENOMEM;
150 
151 	soc_dev_attr->soc_id = "mt7621";
152 	soc_dev_attr->family = "Ralink";
153 	soc_dev_attr->revision = mt7621_get_soc_revision();
154 
155 	soc_dev_attr->data = soc_info_ptr;
156 
157 	soc_dev = soc_device_register(soc_dev_attr);
158 	if (IS_ERR(soc_dev)) {
159 		kfree(soc_dev_attr);
160 		return PTR_ERR(soc_dev);
161 	}
162 
163 	return 0;
164 }
165 device_initcall(mt7621_soc_dev_init);
166 
167 void __init prom_soc_init(struct ralink_soc_info *soc_info)
168 {
169 	/* Early detection of CMP support */
170 	mips_cm_probe();
171 	mips_cpc_probe();
172 
173 	if (mips_cps_numiocu(0)) {
174 		/*
175 		 * mips_cm_probe() wipes out bootloader
176 		 * config for CM regions and we have to configure them
177 		 * again. This SoC cannot talk to pamlbus devices
178 		 * witout proper iocu region set up.
179 		 *
180 		 * FIXME: it would be better to do this with values
181 		 * from DT, but we need this very early because
182 		 * without this we cannot talk to pretty much anything
183 		 * including serial.
184 		 */
185 		write_gcr_reg0_base(MT7621_PALMBUS_BASE);
186 		write_gcr_reg0_mask(~MT7621_PALMBUS_SIZE |
187 				    CM_GCR_REGn_MASK_CMTGT_IOCU0);
188 		__sync();
189 	}
190 
191 	if (mt7621_soc_valid())
192 		soc_info->compatible = "mediatek,mt7621-soc";
193 	else
194 		panic("mt7621: unknown SoC, n0:%08x n1:%08x\n",
195 				mt7621_get_soc_name0(),
196 				mt7621_get_soc_name1());
197 	ralink_soc = MT762X_SOC_MT7621AT;
198 
199 	snprintf(soc_info->sys_type, RAMIPS_SYS_TYPE_LEN,
200 		"MediaTek %s ver:%u eco:%u",
201 		mt7621_get_soc_id(),
202 		mt7621_get_soc_ver(),
203 		mt7621_get_soc_eco());
204 
205 	soc_info->mem_detect = mt7621_memory_detect;
206 
207 	soc_info_ptr = soc_info;
208 
209 	if (!register_cps_smp_ops())
210 		return;
211 	if (!register_vsmp_smp_ops())
212 		return;
213 }
214