root/arch/mips/include/asm/mach-malta/kernel-entry-init.h

INCLUDED FROM

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Chris Dearman (chris@mips.com)
   7  * Copyright (C) 2007 Mips Technologies, Inc.
   8  * Copyright (C) 2014 Imagination Technologies Ltd.
   9  */
  10 #ifndef __ASM_MACH_MIPS_KERNEL_ENTRY_INIT_H
  11 #define __ASM_MACH_MIPS_KERNEL_ENTRY_INIT_H
  12 
  13 #include <asm/regdef.h>
  14 #include <asm/mipsregs.h>
  15 
  16         /*
  17          * Prepare segments for EVA boot:
  18          *
  19          * This is in case the processor boots in legacy configuration
  20          * (SI_EVAReset is de-asserted and CONFIG5.K == 0)
  21          *
  22          * ========================= Mappings =============================
  23          * Virtual memory           Physical memory           Mapping
  24          * 0x00000000 - 0x7fffffff  0x80000000 - 0xfffffffff   MUSUK (kuseg)
  25          *                          Flat 2GB physical memory
  26          *
  27          * 0x80000000 - 0x9fffffff  0x00000000 - 0x1ffffffff   MUSUK (kseg0)
  28          * 0xa0000000 - 0xbf000000  0x00000000 - 0x1ffffffff   MUSUK (kseg1)
  29          * 0xc0000000 - 0xdfffffff             -                 MK  (kseg2)
  30          * 0xe0000000 - 0xffffffff             -                 MK  (kseg3)
  31          *
  32          *
  33          * Lowmem is expanded to 2GB
  34          *
  35          * The following code uses the t0, t1, t2 and ra registers without
  36          * previously preserving them.
  37          *
  38          */
  39         .macro  platform_eva_init
  40 
  41         .set    push
  42         .set    reorder
  43         /*
  44          * Get Config.K0 value and use it to program
  45          * the segmentation registers
  46          */
  47         mfc0    t1, CP0_CONFIG
  48         andi    t1, 0x7 /* CCA */
  49         move    t2, t1
  50         ins     t2, t1, 16, 3
  51         /* SegCtl0 */
  52         li      t0, ((MIPS_SEGCFG_MK << MIPS_SEGCFG_AM_SHIFT) |         \
  53                 (0 << MIPS_SEGCFG_PA_SHIFT) |                           \
  54                 (1 << MIPS_SEGCFG_EU_SHIFT)) |                          \
  55                 (((MIPS_SEGCFG_MK << MIPS_SEGCFG_AM_SHIFT) |            \
  56                 (0 << MIPS_SEGCFG_PA_SHIFT) |                           \
  57                 (1 << MIPS_SEGCFG_EU_SHIFT)) << 16)
  58         or      t0, t2
  59         mtc0    t0, CP0_SEGCTL0
  60 
  61         /* SegCtl1 */
  62         li      t0, ((MIPS_SEGCFG_MUSUK << MIPS_SEGCFG_AM_SHIFT) |      \
  63                 (0 << MIPS_SEGCFG_PA_SHIFT) |                           \
  64                 (2 << MIPS_SEGCFG_C_SHIFT) |                            \
  65                 (1 << MIPS_SEGCFG_EU_SHIFT)) |                          \
  66                 (((MIPS_SEGCFG_MUSUK << MIPS_SEGCFG_AM_SHIFT) |         \
  67                 (0 << MIPS_SEGCFG_PA_SHIFT) |                           \
  68                 (1 << MIPS_SEGCFG_EU_SHIFT)) << 16)
  69         ins     t0, t1, 16, 3
  70         mtc0    t0, CP0_SEGCTL1
  71 
  72         /* SegCtl2 */
  73         li      t0, ((MIPS_SEGCFG_MUSUK << MIPS_SEGCFG_AM_SHIFT) |      \
  74                 (6 << MIPS_SEGCFG_PA_SHIFT) |                           \
  75                 (1 << MIPS_SEGCFG_EU_SHIFT)) |                          \
  76                 (((MIPS_SEGCFG_MUSUK << MIPS_SEGCFG_AM_SHIFT) |         \
  77                 (4 << MIPS_SEGCFG_PA_SHIFT) |                           \
  78                 (1 << MIPS_SEGCFG_EU_SHIFT)) << 16)
  79         or      t0, t2
  80         mtc0    t0, CP0_SEGCTL2
  81 
  82         jal     mips_ihb
  83         mfc0    t0, $16, 5
  84         li      t2, 0x40000000      /* K bit */
  85         or      t0, t0, t2
  86         mtc0    t0, $16, 5
  87         sync
  88         jal     mips_ihb
  89 
  90         .set    pop
  91         .endm
  92 
  93         .macro  kernel_entry_setup
  94 
  95 #ifdef CONFIG_EVA
  96         sync
  97         ehb
  98 
  99         mfc0    t1, CP0_CONFIG
 100         bgez    t1, 9f
 101         mfc0    t0, CP0_CONFIG, 1
 102         bgez    t0, 9f
 103         mfc0    t0, CP0_CONFIG, 2
 104         bgez    t0, 9f
 105         mfc0    t0, CP0_CONFIG, 3
 106         sll     t0, t0, 6   /* SC bit */
 107         bgez    t0, 9f
 108 
 109         platform_eva_init
 110         b       0f
 111 9:
 112         /* Assume we came from YAMON... */
 113         PTR_LA  v0, 0x9fc00534  /* YAMON print */
 114         lw      v0, (v0)
 115         move    a0, zero
 116         PTR_LA  a1, nonsc_processor
 117         jal     v0
 118 
 119         PTR_LA  v0, 0x9fc00520  /* YAMON exit */
 120         lw      v0, (v0)
 121         li      a0, 1
 122         jal     v0
 123 
 124 1:      b       1b
 125         nop
 126         __INITDATA
 127 nonsc_processor:
 128         .asciz  "EVA kernel requires a MIPS core with Segment Control implemented\n"
 129         __FINIT
 130 #endif /* CONFIG_EVA */
 131 0:
 132         .endm
 133 
 134 /*
 135  * Do SMP slave processor setup necessary before we can safely execute C code.
 136  */
 137         .macro  smp_slave_setup
 138 #ifdef CONFIG_EVA
 139         sync
 140         ehb
 141         platform_eva_init
 142 #endif
 143         .endm
 144 
 145 #endif /* __ASM_MACH_MIPS_KERNEL_ENTRY_INIT_H */