arch/ppc/boot/simple/mpc10x_memory.c

   1 /*
   2  * arch/ppc/boot/common/mpc10x_common.c
   3  *
   4  * A routine to find out how much memory the machine has.
   5  *
   6  * Based on:
   7  * arch/ppc/kernel/mpc10x_common.c
   8  *
   9  * Author: Mark A. Greer
  10  *         mgreer@mvista.com
  11  *
  12  * 2001-2002 (c) MontaVista, Software, Inc.  This file is licensed under
  13  * the terms of the GNU General Public License version 2.  This program
  14  * is licensed "as is" without any warranty of any kind, whether express
  15  * or implied.
  16  */
  17
  18 #include <linux/pci.h>
  19 #include <asm/types.h>
  20 #include <asm/io.h>
  21 #include "mpc10x.h"
  22
  23 /*
  24  * *** WARNING - A BAT MUST be set to access the PCI config addr/data regs ***
  25  */
  26
  27 /*
  28  * PCI config space macros, similar to indirect_xxx and early_xxx macros.
  29  * We assume bus 0.
  30  */
  31 #define MPC10X_CFG_read(val, addr, type, op)    *val = op((type)(addr))
  32 #define MPC10X_CFG_write(val, addr, type, op)   op((type *)(addr), (val))
  33
  34 #define MPC10X_PCI_OP(rw, size, type, op, mask)                         \
  35 static void                                                             \
  36 mpc10x_##rw##_config_##size(unsigned int *cfg_addr,                     \
  37                 unsigned int *cfg_data, int devfn, int offset,          \
  38                 type val)                                               \
  39 {                                                                       \
  40         out_be32(cfg_addr,                                              \
  41                  ((offset & 0xfc) << 24) | (devfn << 16)                \
  42                  | (0 << 8) | 0x80);                                    \
  43         MPC10X_CFG_##rw(val, cfg_data + (offset & mask), type, op);     \
  44         return;                                                         \
  45 }
  46
  47 MPC10X_PCI_OP(read, byte,  u8 *, in_8, 3)
  48 MPC10X_PCI_OP(read, dword, u32 *, in_le32, 0)
  49
  50 /*
  51  * Read the memory controller registers to determine the amount of memory in
  52  * the system.  This assumes that the firmware has correctly set up the memory
  53  * controller registers.  On CONFIG_PPC_PREP, we know we are being called
  54  * under a PReP memory map. On all other machines, we assume we are under
  55  * a CHRP memory map.  Further, on CONFIG_PPC_MULTIPLATFORM we must rename
  56  * this function.
  57  */
  58 #ifdef CONFIG_PPC_MULTIPLATFORM
  59 #define get_mem_size mpc10x_get_mem_size
  60 #endif
  61 unsigned long
  62 get_mem_size(void)
  63 {
  64         unsigned int *config_addr, *config_data, val;
  65         unsigned long start, end, total, offset;
  66         int i;
  67         unsigned char bank_enables;
  68
  69 #ifdef CONFIG_PPC_PREP
  70         config_addr = (unsigned int *)MPC10X_MAPA_CNFG_ADDR;
  71         config_data = (unsigned int *)MPC10X_MAPA_CNFG_DATA;
  72 #else
  73         config_addr = (unsigned int *)MPC10X_MAPB_CNFG_ADDR;
  74         config_data = (unsigned int *)MPC10X_MAPB_CNFG_DATA;
  75 #endif
  76
  77         mpc10x_read_config_byte(config_addr, config_data, PCI_DEVFN(0,0),
  78                         MPC10X_MCTLR_MEM_BANK_ENABLES, &bank_enables);
  79
  80         total = 0;
  81
  82         for (i = 0; i < 8; i++) {
  83                 if (bank_enables & (1 << i)) {
  84                         offset = MPC10X_MCTLR_MEM_START_1 + ((i > 3) ? 4 : 0);
  85                         mpc10x_read_config_dword(config_addr, config_data,
  86                                         PCI_DEVFN(0,0), offset, &val);
  87                         start = (val >> ((i & 3) << 3)) & 0xff;
  88
  89                         offset = MPC10X_MCTLR_EXT_MEM_START_1 + ((i>3) ? 4 : 0);
  90                         mpc10x_read_config_dword(config_addr, config_data,
  91                                         PCI_DEVFN(0,0), offset, &val);
  92                         val = (val >> ((i & 3) << 3)) & 0x03;
  93                         start = (val << 28) | (start << 20);
  94
  95                         offset = MPC10X_MCTLR_MEM_END_1 + ((i > 3) ? 4 : 0);
  96                         mpc10x_read_config_dword(config_addr, config_data,
  97                                         PCI_DEVFN(0,0), offset, &val);
  98                         end = (val >> ((i & 3) << 3)) & 0xff;
  99
 100                         offset = MPC10X_MCTLR_EXT_MEM_END_1 + ((i > 3) ? 4 : 0);
 101                         mpc10x_read_config_dword(config_addr, config_data,
 102                                         PCI_DEVFN(0,0), offset, &val);
 103                         val = (val >> ((i & 3) << 3)) & 0x03;
 104                         end = (val << 28) | (end << 20) | 0xfffff;
 105
 106                         total += (end - start + 1);
 107                 }
 108         }
 109
 110         return total;
 111 }