xref: /linux/arch/arm/mach-versatile/integrator.c (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Copyright (C) 2000-2003 Deep Blue Solutions Ltd
4  */
5 #include <linux/types.h>
6 #include <linux/kernel.h>
7 #include <linux/init.h>
8 #include <linux/device.h>
9 #include <linux/export.h>
10 #include <linux/spinlock.h>
11 #include <linux/interrupt.h>
12 #include <linux/irq.h>
13 #include <linux/memblock.h>
14 #include <linux/sched.h>
15 #include <linux/smp.h>
16 #include <linux/amba/bus.h>
17 #include <linux/amba/serial.h>
18 #include <linux/io.h>
19 #include <linux/stat.h>
20 #include <linux/of.h>
21 #include <linux/of_address.h>
22 #include <linux/pgtable.h>
23 
24 #include <asm/mach-types.h>
25 #include <asm/mach/time.h>
26 
27 #include "integrator-hardware.h"
28 #include "integrator-cm.h"
29 #include "integrator.h"
30 
31 static DEFINE_RAW_SPINLOCK(cm_lock);
32 static void __iomem *cm_base;
33 
34 /**
35  * cm_get - get the value from the CM_CTRL register
36  */
37 u32 cm_get(void)
38 {
39 	return readl(cm_base + INTEGRATOR_HDR_CTRL_OFFSET);
40 }
41 
42 /**
43  * cm_control - update the CM_CTRL register.
44  * @mask: bits to change
45  * @set: bits to set
46  */
47 void cm_control(u32 mask, u32 set)
48 {
49 	unsigned long flags;
50 	u32 val;
51 
52 	raw_spin_lock_irqsave(&cm_lock, flags);
53 	val = readl(cm_base + INTEGRATOR_HDR_CTRL_OFFSET) & ~mask;
54 	writel(val | set, cm_base + INTEGRATOR_HDR_CTRL_OFFSET);
55 	raw_spin_unlock_irqrestore(&cm_lock, flags);
56 }
57 
58 void cm_clear_irqs(void)
59 {
60 	/* disable core module IRQs */
61 	writel(0xffffffffU, cm_base + INTEGRATOR_HDR_IC_OFFSET +
62 		IRQ_ENABLE_CLEAR);
63 }
64 
65 static const struct of_device_id cm_match[] = {
66 	{ .compatible = "arm,core-module-integrator"},
67 	{ },
68 };
69 
70 void cm_init(void)
71 {
72 	struct device_node *cm = of_find_matching_node(NULL, cm_match);
73 
74 	if (!cm) {
75 		pr_crit("no core module node found in device tree\n");
76 		return;
77 	}
78 	cm_base = of_iomap(cm, 0);
79 	if (!cm_base) {
80 		pr_crit("could not remap core module\n");
81 		return;
82 	}
83 	cm_clear_irqs();
84 }
85 
86 /*
87  * We need to stop things allocating the low memory; ideally we need a
88  * better implementation of GFP_DMA which does not assume that DMA-able
89  * memory starts at zero.
90  */
91 void __init integrator_reserve(void)
92 {
93 	memblock_reserve(PHYS_OFFSET, __pa(swapper_pg_dir) - PHYS_OFFSET);
94 }
95