arch/mips/sgi-ip22/ip22-mc.c

   1 /*
   2  * ip22-mc.c: Routines for manipulating SGI Memory Controller.
   3  *
   4  * Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
   5  * Copyright (C) 1999 Andrew R. Baker (andrewb@uab.edu) - Indigo2 changes
   6  * Copyright (C) 2003 Ladislav Michl  (ladis@linux-mips.org)
   7  */
   8
   9 #include <linux/init.h>
  10 #include <linux/module.h>
  11 #include <linux/kernel.h>
  12
  13 #include <asm/io.h>
  14 #include <asm/bootinfo.h>
  15 #include <asm/sgialib.h>
  16 #include <asm/sgi/mc.h>
  17 #include <asm/sgi/hpc3.h>
  18 #include <asm/sgi/ip22.h>
  19
  20 struct sgimc_regs *sgimc;
  21
  22 EXPORT_SYMBOL(sgimc);
  23
  24 static inline unsigned long get_bank_addr(unsigned int memconfig)
  25 {
  26         return ((memconfig & SGIMC_MCONFIG_BASEADDR) <<
  27                 ((sgimc->systemid & SGIMC_SYSID_MASKREV) >= 5 ? 24 : 22));
  28 }
  29
  30 static inline unsigned long get_bank_size(unsigned int memconfig)
  31 {
  32         return ((memconfig & SGIMC_MCONFIG_RMASK) + 0x0100) <<
  33                 ((sgimc->systemid & SGIMC_SYSID_MASKREV) >= 5 ? 16 : 14);
  34 }
  35
  36 static inline unsigned int get_bank_config(int bank)
  37 {
  38         unsigned int res = bank > 1 ? sgimc->mconfig1 : sgimc->mconfig0;
  39         return bank % 2 ? res & 0xffff : res >> 16;
  40 }
  41
  42 struct mem {
  43         unsigned long addr;
  44         unsigned long size;
  45 };
  46
  47 /*
  48  * Detect installed memory, do some sanity checks and notify kernel about it
  49  */
  50 static void probe_memory(void)
  51 {
  52         int i, j, found, cnt = 0;
  53         struct mem bank[4];
  54         struct mem space[2] = {{SGIMC_SEG0_BADDR, 0}, {SGIMC_SEG1_BADDR, 0}};
  55
  56         printk(KERN_INFO "MC: Probing memory configuration:\n");
  57         for (i = 0; i < ARRAY_SIZE(bank); i++) {
  58                 unsigned int tmp = get_bank_config(i);
  59                 if (!(tmp & SGIMC_MCONFIG_BVALID))
  60                         continue;
  61
  62                 bank[cnt].size = get_bank_size(tmp);
  63                 bank[cnt].addr = get_bank_addr(tmp);
  64                 printk(KERN_INFO " bank%d: %3ldM @ %08lx\n",
  65                         i, bank[cnt].size / 1024 / 1024, bank[cnt].addr);
  66                 cnt++;
  67         }
  68
  69         /* And you thought bubble sort is dead algorithm... */
  70         do {
  71                 unsigned long addr, size;
  72
  73                 found = 0;
  74                 for (i = 1; i < cnt; i++)
  75                         if (bank[i-1].addr > bank[i].addr) {
  76                                 addr = bank[i].addr;
  77                                 size = bank[i].size;
  78                                 bank[i].addr = bank[i-1].addr;
  79                                 bank[i].size = bank[i-1].size;
  80                                 bank[i-1].addr = addr;
  81                                 bank[i-1].size = size;
  82                                 found = 1;
  83                         }
  84         } while (found);
  85
  86         /* Figure out how are memory banks mapped into spaces */
  87         for (i = 0; i < cnt; i++) {
  88                 found = 0;
  89                 for (j = 0; j < ARRAY_SIZE(space) && !found; j++)
  90                         if (space[j].addr + space[j].size == bank[i].addr) {
  91                                 space[j].size += bank[i].size;
  92                                 found = 1;
  93                         }
  94                 /* There is either hole or overlapping memory */
  95                 if (!found)
  96                         printk(KERN_CRIT "MC: Memory configuration mismatch "
  97                                          "(%08lx), expect Bus Error soon\n",
  98                                          bank[i].addr);
  99         }
 100
 101         for (i = 0; i < ARRAY_SIZE(space); i++)
 102                 if (space[i].size)
 103                         add_memory_region(space[i].addr, space[i].size,
 104                                           BOOT_MEM_RAM);
 105 }
 106
 107 void __init sgimc_init(void)
 108 {
 109         u32 tmp;
 110
 111         /* ioremap can't fail */
 112         sgimc = (struct sgimc_regs *)
 113                 ioremap(SGIMC_BASE, sizeof(struct sgimc_regs));
 114
 115         printk(KERN_INFO "MC: SGI memory controller Revision %d\n",
 116                (int) sgimc->systemid & SGIMC_SYSID_MASKREV);
 117
 118         /* Place the MC into a known state.  This must be done before
 119          * interrupts are first enabled etc.
 120          */
 121
 122         /* Step 0: Make sure we turn off the watchdog in case it's
 123          *         still running (which might be the case after a
 124          *         soft reboot).
 125          */
 126         tmp = sgimc->cpuctrl0;
 127         tmp &= ~SGIMC_CCTRL0_WDOG;
 128         sgimc->cpuctrl0 = tmp;
 129
 130         /* Step 1: The CPU/GIO error status registers will not latch
 131          *         up a new error status until the register has been
 132          *         cleared by the cpu.  These status registers are
 133          *         cleared by writing any value to them.
 134          */
 135         sgimc->cstat = sgimc->gstat = 0;
 136
 137         /* Step 2: Enable all parity checking in cpu control register
 138          *         zero.
 139          */
 140         tmp = sgimc->cpuctrl0;
 141         tmp |= (SGIMC_CCTRL0_EPERRGIO | SGIMC_CCTRL0_EPERRMEM |
 142                 SGIMC_CCTRL0_R4KNOCHKPARR);
 143         sgimc->cpuctrl0 = tmp;
 144
 145         /* Step 3: Setup the MC write buffer depth, this is controlled
 146          *         in cpu control register 1 in the lower 4 bits.
 147          */
 148         tmp = sgimc->cpuctrl1;
 149         tmp &= ~0xf;
 150         tmp |= 0xd;
 151         sgimc->cpuctrl1 = tmp;
 152
 153         /* Step 4: Initialize the RPSS divider register to run as fast
 154          *         as it can correctly operate.  The register is laid
 155          *         out as follows:
 156          *
 157          *         ----------------------------------------
 158          *         |  RESERVED  |   INCREMENT   | DIVIDER |
 159          *         ----------------------------------------
 160          *          31        16 15            8 7       0
 161          *
 162          *         DIVIDER determines how often a 'tick' happens,
 163          *         INCREMENT determines by how the RPSS increment
 164          *         registers value increases at each 'tick'. Thus,
 165          *         for IP22 we get INCREMENT=1, DIVIDER=1 == 0x101
 166          */
 167         sgimc->divider = 0x101;
 168
 169         /* Step 5: Initialize GIO64 arbitrator configuration register.
 170          *
 171          * NOTE: HPC init code in sgihpc_init() must run before us because
 172          *       we need to know Guiness vs. FullHouse and the board
 173          *       revision on this machine. You have been warned.
 174          */
 175
 176         /* First the basic invariants across all GIO64 implementations. */
 177         tmp = SGIMC_GIOPAR_HPC64;       /* All 1st HPC's interface at 64bits */
 178         tmp |= SGIMC_GIOPAR_ONEBUS;     /* Only one physical GIO bus exists */
 179
 180         if (ip22_is_fullhouse()) {
 181                 /* Fullhouse specific settings. */
 182                 if (SGIOC_SYSID_BOARDREV(sgioc->sysid) < 2) {
 183                         tmp |= SGIMC_GIOPAR_HPC264;     /* 2nd HPC at 64bits */
 184                         tmp |= SGIMC_GIOPAR_PLINEEXP0;  /* exp0 pipelines */
 185                         tmp |= SGIMC_GIOPAR_MASTEREXP1; /* exp1 masters */
 186                         tmp |= SGIMC_GIOPAR_RTIMEEXP0;  /* exp0 is realtime */
 187                 } else {
 188                         tmp |= SGIMC_GIOPAR_HPC264;     /* 2nd HPC 64bits */
 189                         tmp |= SGIMC_GIOPAR_PLINEEXP0;  /* exp[01] pipelined */
 190                         tmp |= SGIMC_GIOPAR_PLINEEXP1;
 191                         tmp |= SGIMC_GIOPAR_MASTEREISA; /* EISA masters */
 192                         tmp |= SGIMC_GIOPAR_GFX64;      /* GFX at 64 bits */
 193                 }
 194         } else {
 195                 /* Guiness specific settings. */
 196                 tmp |= SGIMC_GIOPAR_EISA64;     /* MC talks to EISA at 64bits */
 197                 tmp |= SGIMC_GIOPAR_MASTEREISA; /* EISA bus can act as master */
 198         }
 199         sgimc->giopar = tmp;    /* poof */
 200
 201         probe_memory();
 202 }
 203
 204 void __init prom_meminit(void) {}
 205 unsigned long __init prom_free_prom_memory(void)
 206 {
 207         return 0;
 208 }