1// SPDX-License-Identifier: GPL-2.0
2/*
3 * SGI IP30 miscellaneous setup bits.
4 *
5 * Copyright (C) 2004-2007 Stanislaw Skowronek <skylark@unaligned.org>
6 * 2007 Joshua Kinard <kumba@gentoo.org>
7 * 2009 Johannes Dickgreber <tanzy@gmx.de>
8 */
9
10#include <linux/init.h>
11#include <linux/io.h>
12#include <linux/kernel.h>
13#include <linux/types.h>
14#include <linux/percpu.h>
15#include <linux/memblock.h>
16
17#include <asm/bootinfo.h>
18#include <asm/smp-ops.h>
19#include <asm/sgialib.h>
20#include <asm/time.h>
21#include <asm/sgi/heart.h>
22
23#include "ip30-common.h"
24
25/* Structure of accessible HEART registers located in XKPHYS space. */
26struct ip30_heart_regs __iomem *heart_regs = HEART_XKPHYS_BASE;
27
28/*
29 * ARCS will report up to the first 1GB of
30 * memory if queried. Anything beyond that
31 * is marked as reserved.
32 */
33#define IP30_MAX_PROM_MEMORY _AC(0x40000000, UL)
34
35/*
36 * Memory in the Octane starts at 512MB
37 */
38#define IP30_MEMORY_BASE _AC(0x20000000, UL)
39
40/*
41 * If using ARCS to probe for memory, then
42 * remaining memory will start at this offset.
43 */
44#define IP30_REAL_MEMORY_START (IP30_MEMORY_BASE + IP30_MAX_PROM_MEMORY)
45
46#define MEM_SHIFT(x) ((x) >> 20)
47
48static void __init ip30_mem_init(void)
49{
50 unsigned long total_mem;
51 phys_addr_t addr;
52 phys_addr_t size;
53 u32 memcfg;
54 int i;
55
56 total_mem = 0;
57 for (i = 0; i < HEART_MEMORY_BANKS; i++) {
58 memcfg = __raw_readl(addr: &heart_regs->mem_cfg.l[i]);
59 if (!(memcfg & HEART_MEMCFG_VALID))
60 continue;
61
62 addr = memcfg & HEART_MEMCFG_ADDR_MASK;
63 addr <<= HEART_MEMCFG_UNIT_SHIFT;
64 addr += IP30_MEMORY_BASE;
65 size = memcfg & HEART_MEMCFG_SIZE_MASK;
66 size >>= HEART_MEMCFG_SIZE_SHIFT;
67 size += 1;
68 size <<= HEART_MEMCFG_UNIT_SHIFT;
69
70 total_mem += size;
71
72 if (addr >= IP30_REAL_MEMORY_START)
73 memblock_phys_free(base: addr, size);
74 else if ((addr + size) > IP30_REAL_MEMORY_START)
75 memblock_phys_free(IP30_REAL_MEMORY_START,
76 size: size - IP30_MAX_PROM_MEMORY);
77 }
78 pr_info("Detected %luMB of physical memory.\n", MEM_SHIFT(total_mem));
79}
80
81/**
82 * ip30_cpu_time_init - platform time initialization.
83 */
84static void __init ip30_cpu_time_init(void)
85{
86 int cpu = smp_processor_id();
87 u64 heart_compare;
88 unsigned int start, end;
89 int time_diff;
90
91 heart_compare = (heart_read(&heart_regs->count) +
92 (HEART_CYCLES_PER_SEC / 10));
93 start = read_c0_count();
94 while ((heart_read(&heart_regs->count) - heart_compare) & 0x800000)
95 cpu_relax();
96
97 end = read_c0_count();
98 time_diff = (int)end - (int)start;
99 mips_hpt_frequency = time_diff * 10;
100 pr_info("IP30: CPU%d: %d MHz CPU detected.\n", cpu,
101 (mips_hpt_frequency * 2) / 1000000);
102}
103
104void __init ip30_per_cpu_init(void)
105{
106 /* Disable all interrupts. */
107 clear_c0_status(ST0_IM);
108
109 ip30_cpu_time_init();
110#ifdef CONFIG_SMP
111 ip30_install_ipi();
112#endif
113
114 enable_percpu_irq(IP30_HEART_L0_IRQ, IRQ_TYPE_NONE);
115 enable_percpu_irq(IP30_HEART_L1_IRQ, IRQ_TYPE_NONE);
116 enable_percpu_irq(IP30_HEART_L2_IRQ, IRQ_TYPE_NONE);
117 enable_percpu_irq(IP30_HEART_ERR_IRQ, IRQ_TYPE_NONE);
118}
119
120/**
121 * plat_mem_setup - despite the name, misc setup happens here.
122 */
123void __init plat_mem_setup(void)
124{
125 ip30_mem_init();
126
127 /* XXX: Hard lock on /sbin/init if this flag isn't specified. */
128 prom_flags |= PROM_FLAG_DONT_FREE_TEMP;
129
130#ifdef CONFIG_SMP
131 register_smp_ops(&ip30_smp_ops);
132#else
133 ip30_per_cpu_init();
134#endif
135
136 ioport_resource.start = 0;
137 ioport_resource.end = ~0UL;
138 set_io_port_base(IO_BASE);
139}
140

source code of linux/arch/mips/sgi-ip30/ip30-setup.c