xref: /openbmc/linux/arch/mips/ralink/mt7621.c (revision 7fb6f7b0)
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 void __init ralink_of_remap(void)
93 {
94 	rt_sysc_membase = plat_of_remap_node("mediatek,mt7621-sysc");
95 	rt_memc_membase = plat_of_remap_node("mediatek,mt7621-memc");
96 
97 	if (!rt_sysc_membase || !rt_memc_membase)
98 		panic("Failed to remap core resources");
99 }
100 
101 static unsigned int __init mt7621_get_soc_name0(void)
102 {
103 	return __raw_readl(MT7621_SYSC_BASE + SYSC_REG_CHIP_NAME0);
104 }
105 
106 static unsigned int __init mt7621_get_soc_name1(void)
107 {
108 	return __raw_readl(MT7621_SYSC_BASE + SYSC_REG_CHIP_NAME1);
109 }
110 
111 static bool __init mt7621_soc_valid(void)
112 {
113 	if (mt7621_get_soc_name0() == MT7621_CHIP_NAME0 &&
114 			mt7621_get_soc_name1() == MT7621_CHIP_NAME1)
115 		return true;
116 	else
117 		return false;
118 }
119 
120 static const char __init *mt7621_get_soc_id(void)
121 {
122 	if (mt7621_soc_valid())
123 		return "MT7621";
124 	else
125 		return "invalid";
126 }
127 
128 static unsigned int __init mt7621_get_soc_rev(void)
129 {
130 	return __raw_readl(MT7621_SYSC_BASE + SYSC_REG_CHIP_REV);
131 }
132 
133 static unsigned int __init mt7621_get_soc_ver(void)
134 {
135 	return (mt7621_get_soc_rev() >> CHIP_REV_VER_SHIFT) & CHIP_REV_VER_MASK;
136 }
137 
138 static unsigned int __init mt7621_get_soc_eco(void)
139 {
140 	return (mt7621_get_soc_rev() & CHIP_REV_ECO_MASK);
141 }
142 
143 static const char __init *mt7621_get_soc_revision(void)
144 {
145 	if (mt7621_get_soc_rev() == 1 && mt7621_get_soc_eco() == 1)
146 		return "E2";
147 	else
148 		return "E1";
149 }
150 
151 static int __init mt7621_soc_dev_init(void)
152 {
153 	struct soc_device *soc_dev;
154 	struct soc_device_attribute *soc_dev_attr;
155 
156 	soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
157 	if (!soc_dev_attr)
158 		return -ENOMEM;
159 
160 	soc_dev_attr->soc_id = "mt7621";
161 	soc_dev_attr->family = "Ralink";
162 	soc_dev_attr->revision = mt7621_get_soc_revision();
163 
164 	soc_dev_attr->data = soc_info_ptr;
165 
166 	soc_dev = soc_device_register(soc_dev_attr);
167 	if (IS_ERR(soc_dev)) {
168 		kfree(soc_dev_attr);
169 		return PTR_ERR(soc_dev);
170 	}
171 
172 	return 0;
173 }
174 device_initcall(mt7621_soc_dev_init);
175 
176 void __init prom_soc_init(struct ralink_soc_info *soc_info)
177 {
178 	/* Early detection of CMP support */
179 	mips_cm_probe();
180 	mips_cpc_probe();
181 
182 	if (mips_cps_numiocu(0)) {
183 		/*
184 		 * mips_cm_probe() wipes out bootloader
185 		 * config for CM regions and we have to configure them
186 		 * again. This SoC cannot talk to pamlbus devices
187 		 * witout proper iocu region set up.
188 		 *
189 		 * FIXME: it would be better to do this with values
190 		 * from DT, but we need this very early because
191 		 * without this we cannot talk to pretty much anything
192 		 * including serial.
193 		 */
194 		write_gcr_reg0_base(MT7621_PALMBUS_BASE);
195 		write_gcr_reg0_mask(~MT7621_PALMBUS_SIZE |
196 				    CM_GCR_REGn_MASK_CMTGT_IOCU0);
197 		__sync();
198 	}
199 
200 	if (mt7621_soc_valid())
201 		soc_info->compatible = "mediatek,mt7621-soc";
202 	else
203 		panic("mt7621: unknown SoC, n0:%08x n1:%08x\n",
204 				mt7621_get_soc_name0(),
205 				mt7621_get_soc_name1());
206 	ralink_soc = MT762X_SOC_MT7621AT;
207 
208 	snprintf(soc_info->sys_type, RAMIPS_SYS_TYPE_LEN,
209 		"MediaTek %s ver:%u eco:%u",
210 		mt7621_get_soc_id(),
211 		mt7621_get_soc_ver(),
212 		mt7621_get_soc_eco());
213 
214 	soc_info->mem_detect = mt7621_memory_detect;
215 
216 	soc_info_ptr = soc_info;
217 
218 	if (!register_cps_smp_ops())
219 		return;
220 	if (!register_vsmp_smp_ops())
221 		return;
222 }
223