1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  linux/arch/arm/mach-integrator/core.c
4  *
5  *  Copyright (C) 2000-2003 Deep Blue Solutions Ltd
6  */
7 #include <linux/types.h>
8 #include <linux/kernel.h>
9 #include <linux/init.h>
10 #include <linux/device.h>
11 #include <linux/export.h>
12 #include <linux/spinlock.h>
13 #include <linux/interrupt.h>
14 #include <linux/irq.h>
15 #include <linux/memblock.h>
16 #include <linux/sched.h>
17 #include <linux/smp.h>
18 #include <linux/amba/bus.h>
19 #include <linux/amba/serial.h>
20 #include <linux/io.h>
21 #include <linux/stat.h>
22 #include <linux/of.h>
23 #include <linux/of_address.h>
24 #include <linux/pgtable.h>
25 
26 #include <asm/mach-types.h>
27 #include <asm/mach/time.h>
28 
29 #include "hardware.h"
30 #include "cm.h"
31 #include "common.h"
32 
33 static DEFINE_RAW_SPINLOCK(cm_lock);
34 static void __iomem *cm_base;
35 
36 /**
37  * cm_get - get the value from the CM_CTRL register
38  */
cm_get(void)39 u32 cm_get(void)
40 {
41 	return readl(cm_base + INTEGRATOR_HDR_CTRL_OFFSET);
42 }
43 
44 /**
45  * cm_control - update the CM_CTRL register.
46  * @mask: bits to change
47  * @set: bits to set
48  */
cm_control(u32 mask,u32 set)49 void cm_control(u32 mask, u32 set)
50 {
51 	unsigned long flags;
52 	u32 val;
53 
54 	raw_spin_lock_irqsave(&cm_lock, flags);
55 	val = readl(cm_base + INTEGRATOR_HDR_CTRL_OFFSET) & ~mask;
56 	writel(val | set, cm_base + INTEGRATOR_HDR_CTRL_OFFSET);
57 	raw_spin_unlock_irqrestore(&cm_lock, flags);
58 }
59 
cm_clear_irqs(void)60 void cm_clear_irqs(void)
61 {
62 	/* disable core module IRQs */
63 	writel(0xffffffffU, cm_base + INTEGRATOR_HDR_IC_OFFSET +
64 		IRQ_ENABLE_CLEAR);
65 }
66 
67 static const struct of_device_id cm_match[] = {
68 	{ .compatible = "arm,core-module-integrator"},
69 	{ },
70 };
71 
cm_init(void)72 void cm_init(void)
73 {
74 	struct device_node *cm = of_find_matching_node(NULL, cm_match);
75 
76 	if (!cm) {
77 		pr_crit("no core module node found in device tree\n");
78 		return;
79 	}
80 	cm_base = of_iomap(cm, 0);
81 	if (!cm_base) {
82 		pr_crit("could not remap core module\n");
83 		return;
84 	}
85 	cm_clear_irqs();
86 }
87 
88 /*
89  * We need to stop things allocating the low memory; ideally we need a
90  * better implementation of GFP_DMA which does not assume that DMA-able
91  * memory starts at zero.
92  */
integrator_reserve(void)93 void __init integrator_reserve(void)
94 {
95 	memblock_reserve(PHYS_OFFSET, __pa(swapper_pg_dir) - PHYS_OFFSET);
96 }
97