arch/mips/include/asm/mach-pnx8550/kernel-entry-init.h

   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  * Copyright (C) 2005 Embedded Alley Solutions, Inc
   7  */
   8 #ifndef __ASM_MACH_KERNEL_ENTRY_INIT_H
   9 #define __ASM_MACH_KERNEL_ENTRY_INIT_H
  10
  11 #include <asm/cacheops.h>
  12 #include <asm/addrspace.h>
  13
  14 #define CO_CONFIGPR_VALID  0x3F1F41FF    /* valid bits to write to ConfigPR */
  15 #define HAZARD_CP0 nop; nop; nop; nop; nop; nop; nop; nop; nop; nop; nop; nop;
  16 #define CACHE_OPC      0xBC000000  /* MIPS cache instruction opcode */
  17 #define ICACHE_LINE_SIZE        32      /* Instruction cache line size bytes */
  18 #define DCACHE_LINE_SIZE        32      /* Data cache line size in bytes */
  19
  20 #define ICACHE_SET_COUNT        256     /* Instruction cache set count */
  21 #define DCACHE_SET_COUNT        128     /* Data cache set count */
  22
  23 #define ICACHE_SET_SIZE         (ICACHE_SET_COUNT * ICACHE_LINE_SIZE)
  24 #define DCACHE_SET_SIZE         (DCACHE_SET_COUNT * DCACHE_LINE_SIZE)
  25
  26         .macro  kernel_entry_setup
  27         .set    push
  28         .set    noreorder
  29         /*
  30          * PNX8550 entry point, when running a non compressed
  31          * kernel. When loading a zImage, the head.S code in
  32          * arch/mips/zboot/pnx8550 will init the caches and,
  33          * decompress the kernel, and branch to kernel_entry.
  34                  */
  35 cache_begin:    li      t0, (1<<28)
  36         mtc0    t0, CP0_STATUS /* cp0 usable */
  37         HAZARD_CP0
  38
  39         mtc0    zero, CP0_CAUSE
  40         HAZARD_CP0
  41
  42
  43         /* Set static virtual to phys address translation and TLB disabled */
  44         mfc0    t0, CP0_CONFIG, 7
  45         HAZARD_CP0
  46
  47         and     t0, ~((1<<19) | (1<<20))     /* TLB/MAP cleared */
  48         mtc0    t0, CP0_CONFIG, 7
  49         HAZARD_CP0
  50
  51         /* CPU boots with kseg0 cache algo set to 0x2 -- uncached */
  52
  53         init_icache
  54         nop
  55         init_dcache
  56         nop
  57
  58         cachePr4450ICReset
  59         nop
  60
  61         cachePr4450DCReset
  62         nop
  63
  64         /* read ConfigPR into t0 */
  65         mfc0    t0, CP0_CONFIG, 7
  66         HAZARD_CP0
  67
  68         /*  enable the TLB */
  69         or      t0, (1<<19)
  70
  71         /* disable the ICACHE: at least 10x slower */
  72         /* or      t0, (1<<26) */
  73
  74         /* disable the DCACHE; CONFIG_CPU_HAS_LLSC should not be set  */
  75         /* or      t0, (1<<27) */
  76
  77         and     t0, CO_CONFIGPR_VALID
  78
  79         /* enable TLB. */
  80         mtc0    t0, CP0_CONFIG, 7
  81         HAZARD_CP0
  82 cache_end:
  83         /* Setup CMEM_0 to MMIO address space, 2MB */
  84         lui    t0, 0x1BE0
  85         addi   t0, t0, 0x3
  86         mtc0   $8, $22, 4
  87         nop
  88
  89         /* Setup CMEM_1, 128MB */
  90         lui    t0, 0x1000
  91         addi   t0, t0, 0xf
  92         mtc0   $8, $22, 5
  93         nop
  94
  95
  96         /* Setup CMEM_2, 32MB */
  97         lui    t0, 0x1C00
  98         addi   t0, t0, 0xb
  99         mtc0   $8, $22, 6
 100         nop
 101
 102         /* Setup CMEM_3, 0MB */
 103         lui    t0, 0x0
 104         addi   t0, t0, 0x0
 105         mtc0   $8, $22, 7
 106         nop
 107
 108         /* Enable cache */
 109         mfc0    t0, CP0_CONFIG
 110         HAZARD_CP0
 111         and     t0, t0, 0xFFFFFFF8
 112         or      t0, t0, 3
 113         mtc0    t0, CP0_CONFIG
 114         HAZARD_CP0
 115         .set    pop
 116         .endm
 117
 118         .macro  init_icache
 119         .set    push
 120         .set    noreorder
 121
 122         /* Get Cache Configuration */
 123         mfc0    t3, CP0_CONFIG, 1
 124         HAZARD_CP0
 125
 126         /* get cache Line size */
 127
 128         srl   t1, t3, 19   /* C0_CONFIGPR_IL_SHIFT */
 129         andi  t1, t1, 0x7  /* C0_CONFIGPR_IL_MASK */
 130         beq   t1, zero, pr4450_instr_cache_invalidated /* if zero instruction cache is absent */
 131         nop
 132         addiu t0, t1, 1
 133         ori   t1, zero, 1
 134         sllv  t1, t1, t0
 135
 136         /* get max cache Index */
 137         srl   t2, t3, 22  /* C0_CONFIGPR_IS_SHIFT */
 138         andi  t2, t2, 0x7 /* C0_CONFIGPR_IS_MASK */
 139         addiu t0, t2, 6
 140         ori   t2, zero, 1
 141         sllv  t2, t2, t0
 142
 143         /* get max cache way */
 144         srl   t3, t3, 16  /* C0_CONFIGPR_IA_SHIFT */
 145         andi  t3, t3, 0x7 /* C0_CONFIGPR_IA_MASK */
 146         addiu t3, t3, 1
 147
 148         /* total no of cache lines */
 149         multu t2, t3             /* max index * max way */
 150         mflo  t2
 151         addiu t2, t2, -1
 152
 153         move  t0, zero
 154 pr4450_next_instruction_cache_set:
 155         cache  Index_Invalidate_I, 0(t0)
 156         addu  t0, t0, t1         /* add bytes in a line */
 157         bne   t2, zero, pr4450_next_instruction_cache_set
 158         addiu t2, t2, -1   /* reduce no of lines to invalidate by one */
 159 pr4450_instr_cache_invalidated:
 160         .set    pop
 161         .endm
 162
 163         .macro  init_dcache
 164         .set    push
 165         .set    noreorder
 166         move t1, zero
 167
 168         /* Store Tag Information */
 169         mtc0    zero, CP0_TAGLO, 0
 170         HAZARD_CP0
 171
 172         mtc0    zero, CP0_TAGHI, 0
 173         HAZARD_CP0
 174
 175         /* Cache size is 16384 = 512 lines x 32 bytes per line */
 176         or       t2, zero, (128*4)-1  /* 512 lines  */
 177         /* Invalidate all lines */
 178 2:
 179         cache Index_Store_Tag_D, 0(t1)
 180         addiu    t2, t2, -1
 181         bne      t2, zero, 2b
 182         addiu    t1, t1, 32        /* 32 bytes in a line */
 183         .set pop
 184         .endm
 185
 186         .macro  cachePr4450ICReset
 187         .set    push
 188         .set    noreorder
 189
 190         /* Save CP0 status reg on entry; */
 191         /* disable interrupts during cache reset */
 192         mfc0    t0, CP0_STATUS      /* T0 = interrupt status on entry */
 193         HAZARD_CP0
 194
 195         mtc0    zero, CP0_STATUS   /* disable CPU interrupts */
 196         HAZARD_CP0
 197
 198         or      t1, zero, zero              /* T1 = starting cache index (0) */
 199         ori     t2, zero, (256 - 1) /* T2 = inst cache set cnt - 1 */
 200
 201         icache_invd_loop:
 202         /* 9 == register t1 */
 203         .word   CACHE_OPC | (9 << 21) | (Index_Invalidate_I << 16) | \
 204                 (0 * ICACHE_SET_SIZE)  /* invalidate inst cache WAY0 */
 205         .word   CACHE_OPC | (9 << 21) | (Index_Invalidate_I << 16) | \
 206                 (1 * ICACHE_SET_SIZE)  /* invalidate inst cache WAY1 */
 207
 208         addiu   t1, t1, ICACHE_LINE_SIZE    /* T1 = next cache line index */
 209         bne     t2, zero, icache_invd_loop /* T2 = 0 if all sets invalidated */
 210         addiu   t2, t2, -1        /* decrement T2 set cnt (delay slot) */
 211
 212         /* Initialize the latches in the instruction cache tag */
 213         /* that drive the way selection tri-state bus drivers, by doing a */
 214         /* dummy load while the instruction cache is still disabled. */
 215         /* TODO: Is this needed ? */
 216         la      t1, KSEG0            /* T1 = cached memory base address */
 217         lw      zero, 0x0000(t1)      /* (dummy read of first memory word) */
 218
 219         mtc0    t0, CP0_STATUS        /* restore interrupt status on entry */
 220         HAZARD_CP0
 221         .set    pop
 222         .endm
 223
 224         .macro  cachePr4450DCReset
 225         .set    push
 226         .set    noreorder
 227         mfc0    t0, CP0_STATUS           /* T0 = interrupt status on entry */
 228         HAZARD_CP0
 229         mtc0    zero, CP0_STATUS         /* disable CPU interrupts */
 230         HAZARD_CP0
 231
 232         /* Writeback/invalidate entire data cache sets/ways/lines */
 233         or      t1, zero, zero              /* T1 = starting cache index (0) */
 234         ori     t2, zero, (DCACHE_SET_COUNT - 1) /* T2 = data cache set cnt - 1 */
 235
 236         dcache_wbinvd_loop:
 237         /* 9 == register t1 */
 238         .word   CACHE_OPC | (9 << 21) | (Index_Writeback_Inv_D << 16) | \
 239                 (0 * DCACHE_SET_SIZE)  /* writeback/invalidate WAY0 */
 240         .word   CACHE_OPC | (9 << 21) | (Index_Writeback_Inv_D << 16) | \
 241                 (1 * DCACHE_SET_SIZE)  /* writeback/invalidate WAY1 */
 242         .word   CACHE_OPC | (9 << 21) | (Index_Writeback_Inv_D << 16) | \
 243                 (2 * DCACHE_SET_SIZE)  /* writeback/invalidate WAY2 */
 244         .word   CACHE_OPC | (9 << 21) | (Index_Writeback_Inv_D << 16) | \
 245                 (3 * DCACHE_SET_SIZE)  /* writeback/invalidate WAY3 */
 246
 247         addiu   t1, t1, DCACHE_LINE_SIZE  /* T1 = next data cache line index */
 248         bne     t2, zero, dcache_wbinvd_loop /* T2 = 0 when wbinvd entire cache */
 249         addiu   t2, t2, -1          /* decrement T2 set cnt (delay slot) */
 250
 251         /* Initialize the latches in the data cache tag that drive the way
 252         selection tri-state bus drivers, by doing a dummy load while the
 253         data cache is still in the disabled mode.  TODO: Is this needed ? */
 254         la      t1, KSEG0            /* T1 = cached memory base address */
 255         lw      zero, 0x0000(t1)      /* (dummy read of first memory word) */
 256
 257         mtc0    t0, CP0_STATUS       /* restore interrupt status on entry */
 258         HAZARD_CP0
 259         .set    pop
 260         .endm
 261
 262 #endif /* __ASM_MACH_KERNEL_ENTRY_INIT_H */