xref: /openbmc/linux/arch/mips/ralink/mt7621.c (revision 4b33b5ff)
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 
29 int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
30 {
31 	struct resource_entry *entry;
32 	resource_size_t mask;
33 
34 	entry = resource_list_first_type(&bridge->windows, IORESOURCE_MEM);
35 	if (!entry) {
36 		pr_err("Cannot get memory resource\n");
37 		return -EINVAL;
38 	}
39 
40 	if (mips_cps_numiocu(0)) {
41 		/*
42 		 * Hardware doesn't accept mask values with 1s after
43 		 * 0s (e.g. 0xffef), so warn if that's happen
44 		 */
45 		mask = ~(entry->res->end - entry->res->start) & CM_GCR_REGn_MASK_ADDRMASK;
46 		WARN_ON(mask && BIT(ffz(~mask)) - 1 != ~mask);
47 
48 		write_gcr_reg1_base(entry->res->start);
49 		write_gcr_reg1_mask(mask | CM_GCR_REGn_MASK_CMTGT_IOCU0);
50 		pr_info("PCI coherence region base: 0x%08llx, mask/settings: 0x%08llx\n",
51 			(unsigned long long)read_gcr_reg1_base(),
52 			(unsigned long long)read_gcr_reg1_mask());
53 	}
54 
55 	return 0;
56 }
57 
58 phys_addr_t mips_cpc_default_phys_base(void)
59 {
60 	panic("Cannot detect cpc address");
61 }
62 
63 static bool __init mt7621_addr_wraparound_test(phys_addr_t size)
64 {
65 	void *dm = (void *)KSEG1ADDR(&detect_magic);
66 
67 	if (CPHYSADDR(dm + size) >= MT7621_LOWMEM_MAX_SIZE)
68 		return true;
69 	__raw_writel(MT7621_MEM_TEST_PATTERN, dm);
70 	if (__raw_readl(dm) != __raw_readl(dm + size))
71 		return false;
72 	__raw_writel(~MT7621_MEM_TEST_PATTERN, dm);
73 	return __raw_readl(dm) == __raw_readl(dm + size);
74 }
75 
76 static void __init mt7621_memory_detect(void)
77 {
78 	phys_addr_t size;
79 
80 	for (size = 32 * SZ_1M; size <= 256 * SZ_1M; size <<= 1) {
81 		if (mt7621_addr_wraparound_test(size)) {
82 			memblock_add(MT7621_LOWMEM_BASE, size);
83 			return;
84 		}
85 	}
86 
87 	memblock_add(MT7621_LOWMEM_BASE, MT7621_LOWMEM_MAX_SIZE);
88 	memblock_add(MT7621_HIGHMEM_BASE, MT7621_HIGHMEM_SIZE);
89 }
90 
91 void __init ralink_of_remap(void)
92 {
93 	rt_sysc_membase = plat_of_remap_node("mediatek,mt7621-sysc");
94 	rt_memc_membase = plat_of_remap_node("mediatek,mt7621-memc");
95 
96 	if (!rt_sysc_membase || !rt_memc_membase)
97 		panic("Failed to remap core resources");
98 }
99 
100 static void soc_dev_init(struct ralink_soc_info *soc_info, u32 rev)
101 {
102 	struct soc_device *soc_dev;
103 	struct soc_device_attribute *soc_dev_attr;
104 
105 	soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
106 	if (!soc_dev_attr)
107 		return;
108 
109 	soc_dev_attr->soc_id = "mt7621";
110 	soc_dev_attr->family = "Ralink";
111 
112 	if (((rev >> CHIP_REV_VER_SHIFT) & CHIP_REV_VER_MASK) == 1 &&
113 	    (rev & CHIP_REV_ECO_MASK) == 1)
114 		soc_dev_attr->revision = "E2";
115 	else
116 		soc_dev_attr->revision = "E1";
117 
118 	soc_dev_attr->data = soc_info;
119 
120 	soc_dev = soc_device_register(soc_dev_attr);
121 	if (IS_ERR(soc_dev)) {
122 		kfree(soc_dev_attr);
123 		return;
124 	}
125 }
126 
127 void __init prom_soc_init(struct ralink_soc_info *soc_info)
128 {
129 	void __iomem *sysc = (void __iomem *) KSEG1ADDR(MT7621_SYSC_BASE);
130 	unsigned char *name = NULL;
131 	u32 n0;
132 	u32 n1;
133 	u32 rev;
134 
135 	/* Early detection of CMP support */
136 	mips_cm_probe();
137 	mips_cpc_probe();
138 
139 	if (mips_cps_numiocu(0)) {
140 		/*
141 		 * mips_cm_probe() wipes out bootloader
142 		 * config for CM regions and we have to configure them
143 		 * again. This SoC cannot talk to pamlbus devices
144 		 * witout proper iocu region set up.
145 		 *
146 		 * FIXME: it would be better to do this with values
147 		 * from DT, but we need this very early because
148 		 * without this we cannot talk to pretty much anything
149 		 * including serial.
150 		 */
151 		write_gcr_reg0_base(MT7621_PALMBUS_BASE);
152 		write_gcr_reg0_mask(~MT7621_PALMBUS_SIZE |
153 				    CM_GCR_REGn_MASK_CMTGT_IOCU0);
154 		__sync();
155 	}
156 
157 	n0 = __raw_readl(sysc + SYSC_REG_CHIP_NAME0);
158 	n1 = __raw_readl(sysc + SYSC_REG_CHIP_NAME1);
159 
160 	if (n0 == MT7621_CHIP_NAME0 && n1 == MT7621_CHIP_NAME1) {
161 		name = "MT7621";
162 		soc_info->compatible = "mediatek,mt7621-soc";
163 	} else {
164 		panic("mt7621: unknown SoC, n0:%08x n1:%08x\n", n0, n1);
165 	}
166 	ralink_soc = MT762X_SOC_MT7621AT;
167 	rev = __raw_readl(sysc + SYSC_REG_CHIP_REV);
168 
169 	snprintf(soc_info->sys_type, RAMIPS_SYS_TYPE_LEN,
170 		"MediaTek %s ver:%u eco:%u",
171 		name,
172 		(rev >> CHIP_REV_VER_SHIFT) & CHIP_REV_VER_MASK,
173 		(rev & CHIP_REV_ECO_MASK));
174 
175 	soc_info->mem_detect = mt7621_memory_detect;
176 
177 	soc_dev_init(soc_info, rev);
178 
179 	if (!register_cps_smp_ops())
180 		return;
181 	if (!register_cmp_smp_ops())
182 		return;
183 	if (!register_vsmp_smp_ops())
184 		return;
185 }
186