xref: /linux/arch/arm/mach-ux500/cpu-db8500.c (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2008-2009 ST-Ericsson SA
4  *
5  * Author: Srinidhi KASAGAR <srinidhi.kasagar@stericsson.com>
6  */
7 #include <linux/types.h>
8 #include <linux/init.h>
9 #include <linux/device.h>
10 #include <linux/amba/bus.h>
11 #include <linux/interrupt.h>
12 #include <linux/irq.h>
13 #include <linux/irqchip.h>
14 #include <linux/irqchip/arm-gic.h>
15 #include <linux/mfd/dbx500-prcmu.h>
16 #include <linux/platform_data/arm-ux500-pm.h>
17 #include <linux/platform_device.h>
18 #include <linux/io.h>
19 #include <linux/of.h>
20 #include <linux/of_address.h>
21 #include <linux/of_platform.h>
22 #include <linux/regulator/machine.h>
23 
24 #include <asm/outercache.h>
25 #include <asm/hardware/cache-l2x0.h>
26 #include <asm/mach/map.h>
27 #include <asm/mach/arch.h>
28 
29 static int __init ux500_l2x0_unlock(void)
30 {
31 	int i;
32 	struct device_node *np;
33 	void __iomem *l2x0_base;
34 
35 	np = of_find_compatible_node(NULL, NULL, "arm,pl310-cache");
36 	l2x0_base = of_iomap(np, 0);
37 	of_node_put(np);
38 	if (!l2x0_base)
39 		return -ENODEV;
40 
41 	/*
42 	 * Unlock Data and Instruction Lock if locked. Ux500 U-Boot versions
43 	 * apparently locks both caches before jumping to the kernel. The
44 	 * l2x0 core will not touch the unlock registers if the l2x0 is
45 	 * already enabled, so we do it right here instead. The PL310 has
46 	 * 8 sets of registers, one per possible CPU.
47 	 */
48 	for (i = 0; i < 8; i++) {
49 		writel_relaxed(0x0, l2x0_base + L2X0_LOCKDOWN_WAY_D_BASE +
50 			       i * L2X0_LOCKDOWN_STRIDE);
51 		writel_relaxed(0x0, l2x0_base + L2X0_LOCKDOWN_WAY_I_BASE +
52 			       i * L2X0_LOCKDOWN_STRIDE);
53 	}
54 	iounmap(l2x0_base);
55 	return 0;
56 }
57 
58 static void ux500_l2c310_write_sec(unsigned long val, unsigned reg)
59 {
60 	/*
61 	 * We can't write to secure registers as we are in non-secure
62 	 * mode, until we have some SMI service available.
63 	 */
64 }
65 
66 /*
67  * FIXME: Should we set up the GPIO domain here?
68  *
69  * The problem is that we cannot put the interrupt resources into the platform
70  * device until the irqdomain has been added. Right now, we set the GIC interrupt
71  * domain from init_irq(), then load the gpio driver from
72  * core_initcall(nmk_gpio_init) and add the platform devices from
73  * arch_initcall(customize_machine).
74  *
75  * This feels fragile because it depends on the gpio device getting probed
76  * _before_ any device uses the gpio interrupts.
77 */
78 static void __init ux500_init_irq(void)
79 {
80 	struct device_node *np;
81 	struct resource r;
82 
83 	irqchip_init();
84 	prcmu_early_init();
85 	np = of_find_compatible_node(NULL, NULL, "stericsson,db8500-prcmu");
86 	of_address_to_resource(np, 0, &r);
87 	of_node_put(np);
88 	if (!r.start) {
89 		pr_err("could not find PRCMU base resource\n");
90 		return;
91 	}
92 	ux500_pm_init(r.start, r.end-r.start);
93 
94 	/* Unlock before init */
95 	ux500_l2x0_unlock();
96 	outer_cache.write_sec = ux500_l2c310_write_sec;
97 }
98 
99 static void ux500_restart(enum reboot_mode mode, const char *cmd)
100 {
101 	local_irq_disable();
102 	local_fiq_disable();
103 
104 	prcmu_system_reset(0);
105 }
106 
107 static const struct of_device_id u8500_local_bus_nodes[] = {
108 	/* only create devices below soc node */
109 	{ .compatible = "stericsson,db8500", },
110 	{ .compatible = "simple-bus"},
111 	{ },
112 };
113 
114 static void __init u8500_init_machine(void)
115 {
116 	of_platform_populate(NULL, u8500_local_bus_nodes,
117 			     NULL, NULL);
118 }
119 
120 static const char * stericsson_dt_platform_compat[] = {
121 	"st-ericsson,u8500",
122 	"st-ericsson,u9500",
123 	NULL,
124 };
125 
126 DT_MACHINE_START(U8500_DT, "ST-Ericsson Ux5x0 platform (Device Tree Support)")
127 	.l2c_aux_val    = 0,
128 	.l2c_aux_mask	= ~0,
129 	.init_irq	= ux500_init_irq,
130 	.init_machine	= u8500_init_machine,
131 	.dt_compat      = stericsson_dt_platform_compat,
132 	.restart        = ux500_restart,
133 MACHINE_END
134