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. */
  25 struct 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
  47 static 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  */
  83 static 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
 103 void __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  */
 122 void __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 }