1 /*
2  * Keystone2 based boards and SOC related code.
3  *
4  * Copyright 2013 Texas Instruments, Inc.
5  *	Cyril Chemparathy <cyril@ti.com>
6  *	Santosh Shilimkar <santosh.shillimkar@ti.com>
7  *
8  * This program is free software; you can redistribute it and/or modify it
9  * under the terms and conditions of the GNU General Public License,
10  * version 2, as published by the Free Software Foundation.
11  */
12 #include <linux/io.h>
13 #include <linux/of.h>
14 #include <linux/init.h>
15 #include <linux/of_platform.h>
16 #include <linux/of_address.h>
17 #include <linux/memblock.h>
18 
19 #include <asm/setup.h>
20 #include <asm/mach/map.h>
21 #include <asm/mach/arch.h>
22 #include <asm/mach/time.h>
23 #include <asm/smp_plat.h>
24 #include <asm/memory.h>
25 
26 #include "memory.h"
27 
28 #include "keystone.h"
29 
30 static struct notifier_block platform_nb;
31 static unsigned long keystone_dma_pfn_offset __read_mostly;
32 
33 static int keystone_platform_notifier(struct notifier_block *nb,
34 				      unsigned long event, void *data)
35 {
36 	struct device *dev = data;
37 
38 	if (event != BUS_NOTIFY_ADD_DEVICE)
39 		return NOTIFY_DONE;
40 
41 	if (!dev)
42 		return NOTIFY_BAD;
43 
44 	if (!dev->of_node) {
45 		dev->dma_pfn_offset = keystone_dma_pfn_offset;
46 		dev_err(dev, "set dma_pfn_offset%08lx\n",
47 			dev->dma_pfn_offset);
48 	}
49 	return NOTIFY_OK;
50 }
51 
52 static void __init keystone_init(void)
53 {
54 	keystone_pm_runtime_init();
55 	if (platform_nb.notifier_call)
56 		bus_register_notifier(&platform_bus_type, &platform_nb);
57 	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
58 }
59 
60 static phys_addr_t keystone_virt_to_idmap(unsigned long x)
61 {
62 	return (phys_addr_t)(x) - CONFIG_PAGE_OFFSET + KEYSTONE_LOW_PHYS_START;
63 }
64 
65 static void __init keystone_init_meminfo(void)
66 {
67 	bool lpae = IS_ENABLED(CONFIG_ARM_LPAE);
68 	bool pvpatch = IS_ENABLED(CONFIG_ARM_PATCH_PHYS_VIRT);
69 	phys_addr_t offset = PHYS_OFFSET - KEYSTONE_LOW_PHYS_START;
70 	phys_addr_t mem_start, mem_end;
71 
72 	mem_start = memblock_start_of_DRAM();
73 	mem_end = memblock_end_of_DRAM();
74 
75 	/* nothing to do if we are running out of the <32-bit space */
76 	if (mem_start >= KEYSTONE_LOW_PHYS_START &&
77 	    mem_end   <= KEYSTONE_LOW_PHYS_END)
78 		return;
79 
80 	if (!lpae || !pvpatch) {
81 		pr_crit("Enable %s%s%s to run outside 32-bit space\n",
82 		      !lpae ? __stringify(CONFIG_ARM_LPAE) : "",
83 		      (!lpae && !pvpatch) ? " and " : "",
84 		      !pvpatch ? __stringify(CONFIG_ARM_PATCH_PHYS_VIRT) : "");
85 	}
86 
87 	if (mem_start < KEYSTONE_HIGH_PHYS_START ||
88 	    mem_end   > KEYSTONE_HIGH_PHYS_END) {
89 		pr_crit("Invalid address space for memory (%08llx-%08llx)\n",
90 		      (u64)mem_start, (u64)mem_end);
91 	}
92 
93 	offset += KEYSTONE_HIGH_PHYS_START;
94 	__pv_phys_pfn_offset = PFN_DOWN(offset);
95 	__pv_offset = (offset - PAGE_OFFSET);
96 
97 	/* Populate the arch idmap hook */
98 	arch_virt_to_idmap = keystone_virt_to_idmap;
99 	platform_nb.notifier_call = keystone_platform_notifier;
100 	keystone_dma_pfn_offset = PFN_DOWN(KEYSTONE_HIGH_PHYS_START -
101 						KEYSTONE_LOW_PHYS_START);
102 
103 	pr_info("Switching to high address space at 0x%llx\n", (u64)offset);
104 }
105 
106 static const char *keystone_match[] __initconst = {
107 	"ti,keystone",
108 	NULL,
109 };
110 
111 DT_MACHINE_START(KEYSTONE, "Keystone")
112 #if defined(CONFIG_ZONE_DMA) && defined(CONFIG_ARM_LPAE)
113 	.dma_zone_size	= SZ_2G,
114 #endif
115 	.smp		= smp_ops(keystone_smp_ops),
116 	.init_machine	= keystone_init,
117 	.dt_compat	= keystone_match,
118 	.init_meminfo   = keystone_init_meminfo,
119 MACHINE_END
120