root/arch/parisc/kernel/relocate_kernel.S

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #include <linux/linkage.h>
   3 #include <linux/kexec.h>
   4 
   5 #include <asm/assembly.h>
   6 #include <asm/asm-offsets.h>
   7 #include <asm/page.h>
   8 #include <asm/setup.h>
   9 #include <asm/psw.h>
  10 
  11 .level PA_ASM_LEVEL
  12 
  13 .macro  kexec_param name
  14 .align 8
  15 ENTRY(kexec\()_\name)
  16 #ifdef CONFIG_64BIT
  17         .dword 0
  18 #else
  19         .word 0
  20 #endif
  21 
  22 ENTRY(kexec\()_\name\()_offset)
  23         .word kexec\()_\name - relocate_new_kernel
  24 .endm
  25 
  26 .text
  27 
  28 /* args:
  29  * r26 - kimage->head
  30  * r25 - start address of kernel
  31  * r24 - physical address of relocate code
  32  */
  33 
  34 ENTRY_CFI(relocate_new_kernel)
  35 0:      copy    %arg1, %rp
  36         /* disable I and Q bit, so we are allowed to execute RFI */
  37         rsm PSW_SM_I, %r0
  38         nop
  39         nop
  40         nop
  41         nop
  42         nop
  43         nop
  44         nop
  45 
  46         rsm PSW_SM_Q, %r0
  47         nop
  48         nop
  49         nop
  50         nop
  51         nop
  52         nop
  53         nop
  54 
  55         /*
  56          * After return-from-interrupt, we want to run without Code/Data
  57          * translation enabled just like on a normal boot.
  58          */
  59 
  60         /* calculate new physical execution address */
  61         ldo     1f-0b(%arg2), %r1
  62         mtctl   %r0, %cr17 /* IIASQ */
  63         mtctl   %r0, %cr17 /* IIASQ */
  64         mtctl   %r1, %cr18 /* IIAOQ */
  65         ldo     4(%r1),%r1
  66         mtctl   %r1, %cr18 /* IIAOQ */
  67 #ifdef CONFIG_64BIT
  68         depdi,z 1, PSW_W_BIT, 1, %r1
  69         mtctl   %r1, %cr22 /* IPSW */
  70 #else
  71         mtctl   %r0, %cr22 /* IPSW */
  72 #endif
  73         /* lets go... */
  74         rfi
  75 1:      nop
  76         nop
  77 
  78 .Lloop:
  79         LDREG,ma        REG_SZ(%arg0), %r3
  80         /* If crash kernel, no copy needed */
  81         cmpib,COND(=),n 0,%r3,boot
  82 
  83         bb,<,n          %r3, 31 - IND_DONE_BIT, boot
  84         bb,>=,n         %r3, 31 - IND_INDIRECTION_BIT, .Lnotind
  85         /* indirection, load and restart */
  86         movb            %r3, %arg0, .Lloop
  87         depi            0, 31, PAGE_SHIFT, %arg0
  88 
  89 .Lnotind:
  90         bb,>=,n         %r3, 31 - IND_DESTINATION_BIT, .Lnotdest
  91         b               .Lloop
  92         copy            %r3, %r20
  93 
  94 .Lnotdest:
  95         bb,>=           %r3, 31 - IND_SOURCE_BIT, .Lloop
  96         depi            0, 31, PAGE_SHIFT, %r3
  97         copy            %r3, %r21
  98 
  99         /* copy page */
 100         copy            %r0, %r18
 101         zdepi           1, 31 - PAGE_SHIFT, 1, %r18
 102         add             %r20, %r18, %r17
 103 
 104         depi            0, 31, PAGE_SHIFT, %r20
 105 .Lcopy:
 106         copy            %r20, %r12
 107         LDREG,ma        REG_SZ(%r21), %r8
 108         LDREG,ma        REG_SZ(%r21), %r9
 109         LDREG,ma        REG_SZ(%r21), %r10
 110         LDREG,ma        REG_SZ(%r21), %r11
 111         STREG,ma        %r8, REG_SZ(%r20)
 112         STREG,ma        %r9, REG_SZ(%r20)
 113         STREG,ma        %r10, REG_SZ(%r20)
 114         STREG,ma        %r11, REG_SZ(%r20)
 115 
 116 #ifndef CONFIG_64BIT
 117         LDREG,ma        REG_SZ(%r21), %r8
 118         LDREG,ma        REG_SZ(%r21), %r9
 119         LDREG,ma        REG_SZ(%r21), %r10
 120         LDREG,ma        REG_SZ(%r21), %r11
 121         STREG,ma        %r8, REG_SZ(%r20)
 122         STREG,ma        %r9, REG_SZ(%r20)
 123         STREG,ma        %r10, REG_SZ(%r20)
 124         STREG,ma        %r11, REG_SZ(%r20)
 125 #endif
 126 
 127         fdc             %r0(%r12)
 128         cmpb,COND(<<)   %r20,%r17,.Lcopy
 129         fic             (%sr4, %r12)
 130         b,n             .Lloop
 131 
 132 boot:
 133         mtctl   %r0, %cr15
 134 
 135         LDREG   kexec_free_mem-0b(%arg2), %arg0
 136         LDREG   kexec_cmdline-0b(%arg2), %arg1
 137         LDREG   kexec_initrd_end-0b(%arg2), %arg3
 138         LDREG   kexec_initrd_start-0b(%arg2), %arg2
 139         bv,n %r0(%rp)
 140 
 141 ENDPROC_CFI(relocate_new_kernel);
 142 
 143 ENTRY(relocate_new_kernel_size)
 144        .word relocate_new_kernel_size - relocate_new_kernel
 145 
 146 kexec_param cmdline
 147 kexec_param initrd_start
 148 kexec_param initrd_end
 149 kexec_param free_mem