1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Versatile board support using the device tree
4  *
5  *  Copyright (C) 2010 Secret Lab Technologies Ltd.
6  *  Copyright (C) 2009 Jeremy Kerr <jeremy.kerr@canonical.com>
7  *  Copyright (C) 2004 ARM Limited
8  *  Copyright (C) 2000 Deep Blue Solutions Ltd
9  */
10 
11 #include <linux/init.h>
12 #include <linux/io.h>
13 #include <linux/of.h>
14 #include <linux/of_address.h>
15 #include <linux/of_irq.h>
16 #include <linux/of_platform.h>
17 #include <linux/slab.h>
18 #include <linux/amba/bus.h>
19 #include <linux/amba/mmci.h>
20 #include <asm/mach-types.h>
21 #include <asm/mach/arch.h>
22 #include <asm/mach/map.h>
23 
24 /* macro to get at MMIO space when running virtually */
25 #define IO_ADDRESS(x)		(((x) & 0x0fffffff) + (((x) >> 4) & 0x0f000000) + 0xf0000000)
26 #define __io_address(n)		((void __iomem __force *)IO_ADDRESS(n))
27 
28 /*
29  * ------------------------------------------------------------------------
30  *  Versatile Registers
31  * ------------------------------------------------------------------------
32  */
33 #define VERSATILE_SYS_PCICTL_OFFSET           0x44
34 #define VERSATILE_SYS_MCI_OFFSET              0x48
35 
36 /*
37  * VERSATILE peripheral addresses
38  */
39 #define VERSATILE_MMCI0_BASE           0x10005000	/* MMC interface */
40 #define VERSATILE_MMCI1_BASE           0x1000B000	/* MMC Interface */
41 #define VERSATILE_SCTL_BASE            0x101E0000	/* System controller */
42 
43 /*
44  * System controller bit assignment
45  */
46 #define VERSATILE_REFCLK	0
47 #define VERSATILE_TIMCLK	1
48 
49 #define VERSATILE_TIMER1_EnSel	15
50 #define VERSATILE_TIMER2_EnSel	17
51 #define VERSATILE_TIMER3_EnSel	19
52 #define VERSATILE_TIMER4_EnSel	21
53 
54 static void __iomem *versatile_sys_base;
55 
mmc_status(struct device * dev)56 static unsigned int mmc_status(struct device *dev)
57 {
58 	struct amba_device *adev = container_of(dev, struct amba_device, dev);
59 	u32 mask;
60 
61 	if (adev->res.start == VERSATILE_MMCI0_BASE)
62 		mask = 1;
63 	else
64 		mask = 2;
65 
66 	return readl(versatile_sys_base + VERSATILE_SYS_MCI_OFFSET) & mask;
67 }
68 
69 static struct mmci_platform_data mmc0_plat_data = {
70 	.ocr_mask	= MMC_VDD_32_33|MMC_VDD_33_34,
71 	.status		= mmc_status,
72 };
73 
74 static struct mmci_platform_data mmc1_plat_data = {
75 	.ocr_mask	= MMC_VDD_32_33|MMC_VDD_33_34,
76 	.status		= mmc_status,
77 };
78 
79 /*
80  * Lookup table for attaching a specific name and platform_data pointer to
81  * devices as they get created by of_platform_populate().  Ideally this table
82  * would not exist, but the current clock implementation depends on some devices
83  * having a specific name.
84  */
85 struct of_dev_auxdata versatile_auxdata_lookup[] __initdata = {
86 	OF_DEV_AUXDATA("arm,primecell", VERSATILE_MMCI0_BASE, "fpga:05", &mmc0_plat_data),
87 	OF_DEV_AUXDATA("arm,primecell", VERSATILE_MMCI1_BASE, "fpga:0b", &mmc1_plat_data),
88 	{}
89 };
90 
91 static struct map_desc versatile_io_desc[] __initdata __maybe_unused = {
92 	{
93 		.virtual	=  IO_ADDRESS(VERSATILE_SCTL_BASE),
94 		.pfn		= __phys_to_pfn(VERSATILE_SCTL_BASE),
95 		.length		= SZ_4K * 9,
96 		.type		= MT_DEVICE
97 	}
98 };
99 
versatile_map_io(void)100 static void __init versatile_map_io(void)
101 {
102 	debug_ll_io_init();
103 	iotable_init(versatile_io_desc, ARRAY_SIZE(versatile_io_desc));
104 }
105 
versatile_init_early(void)106 static void __init versatile_init_early(void)
107 {
108 	u32 val;
109 
110 	/*
111 	 * set clock frequency:
112 	 *	VERSATILE_REFCLK is 32KHz
113 	 *	VERSATILE_TIMCLK is 1MHz
114 	 */
115 	val = readl(__io_address(VERSATILE_SCTL_BASE));
116 	writel((VERSATILE_TIMCLK << VERSATILE_TIMER1_EnSel) |
117 	       (VERSATILE_TIMCLK << VERSATILE_TIMER2_EnSel) |
118 	       (VERSATILE_TIMCLK << VERSATILE_TIMER3_EnSel) |
119 	       (VERSATILE_TIMCLK << VERSATILE_TIMER4_EnSel) | val,
120 	       __io_address(VERSATILE_SCTL_BASE));
121 }
122 
versatile_dt_pci_init(void)123 static void __init versatile_dt_pci_init(void)
124 {
125 	u32 val;
126 	struct device_node *np;
127 	struct property *newprop;
128 
129 	np = of_find_compatible_node(NULL, NULL, "arm,versatile-pci");
130 	if (!np)
131 		return;
132 
133 	/* Check if PCI backplane is detected */
134 	val = readl(versatile_sys_base + VERSATILE_SYS_PCICTL_OFFSET);
135 	if (val & 1) {
136 		/*
137 		 * Enable PCI accesses. Note that the documentaton is
138 		 * inconsistent whether or not this is needed, but the old
139 		 * driver had it so we will keep it.
140 		 */
141 		writel(1, versatile_sys_base + VERSATILE_SYS_PCICTL_OFFSET);
142 		goto out_put_node;
143 	}
144 
145 	newprop = kzalloc(sizeof(*newprop), GFP_KERNEL);
146 	if (!newprop)
147 		goto out_put_node;
148 
149 	newprop->name = kstrdup("status", GFP_KERNEL);
150 	newprop->value = kstrdup("disabled", GFP_KERNEL);
151 	newprop->length = sizeof("disabled");
152 	of_update_property(np, newprop);
153 
154 	pr_info("Not plugged into PCI backplane!\n");
155 
156 out_put_node:
157 	of_node_put(np);
158 }
159 
versatile_dt_init(void)160 static void __init versatile_dt_init(void)
161 {
162 	struct device_node *np;
163 
164 	np = of_find_compatible_node(NULL, NULL, "arm,core-module-versatile");
165 	if (np)
166 		versatile_sys_base = of_iomap(np, 0);
167 	WARN_ON(!versatile_sys_base);
168 
169 	versatile_dt_pci_init();
170 
171 	of_platform_default_populate(NULL, versatile_auxdata_lookup, NULL);
172 }
173 
174 static const char *const versatile_dt_match[] __initconst = {
175 	"arm,versatile-ab",
176 	"arm,versatile-pb",
177 	NULL,
178 };
179 
180 DT_MACHINE_START(VERSATILE_PB, "ARM-Versatile (Device Tree Support)")
181 	.map_io		= versatile_map_io,
182 	.init_early	= versatile_init_early,
183 	.init_machine	= versatile_dt_init,
184 	.dt_compat	= versatile_dt_match,
185 MACHINE_END
186