LXR linux/arch/mips/sgi-ip30/ip30-setup.c

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