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  1. /* This is where the SPARC/LEON3 starts
  2. * Copyright (C) 2007,
  3. * Daniel Hellstrom, daniel@gaisler.com
  4. *
  5. * SPDX-License-Identifier: GPL-2.0+
  6. */
  7. #include <asm-offsets.h>
  8. #include <config.h>
  9. #include <asm/asmmacro.h>
  10. #include <asm/winmacro.h>
  11. #include <asm/psr.h>
  12. #include <asm/stack.h>
  13. #include <asm/leon.h>
  14. #include <version.h>
  15. /* Entry for traps which jump to a programmer-specified trap handler. */
  16. #define TRAPR(H) \
  17. wr %g0, 0xfe0, %psr; \
  18. mov %g0, %tbr; \
  19. ba (H); \
  20. mov %g0, %wim;
  21. #define TRAP(H) \
  22. mov %psr, %l0; \
  23. ba (H); \
  24. nop; nop;
  25. #define TRAPI(ilevel) \
  26. mov ilevel, %l7; \
  27. mov %psr, %l0; \
  28. b _irq_entry; \
  29. mov %wim, %l3
  30. /* Unexcpected trap will halt the processor by forcing it to error state */
  31. #undef BAD_TRAP
  32. #define BAD_TRAP ta 0; nop; nop; nop;
  33. /* Software trap. Treat as BAD_TRAP for the time being... */
  34. #define SOFT_TRAP TRAP(_hwerr)
  35. #define PSR_INIT 0x1FC0 /* Disable traps, set s and ps */
  36. #define WIM_INIT 2
  37. /* All traps low-level code here must end with this macro. */
  38. #define RESTORE_ALL b ret_trap_entry; clr %l6;
  39. #define WRITE_PAUSE nop;nop;nop
  40. WINDOWSIZE = (16 * 4)
  41. ARGPUSHSIZE = (6 * 4)
  42. ARGPUSH = (WINDOWSIZE + 4)
  43. MINFRAME = (WINDOWSIZE + ARGPUSHSIZE + 4)
  44. /* Number of register windows */
  45. #ifndef CONFIG_SYS_SPARC_NWINDOWS
  46. #error Must define number of SPARC register windows, default is 8
  47. #endif
  48. #define STACK_ALIGN 8
  49. #define SA(X) (((X)+(STACK_ALIGN-1)) & ~(STACK_ALIGN-1))
  50. .section ".start", "ax"
  51. .globl _start, start, _trap_table
  52. .globl _irq_entry, nmi_trap
  53. .globl _reset_reloc
  54. /* at address 0
  55. * Hardware traps
  56. */
  57. start:
  58. _start:
  59. _trap_table:
  60. TRAPR(_hardreset); ! 00 reset trap
  61. BAD_TRAP; ! 01 instruction_access_exception
  62. BAD_TRAP; ! 02 illegal_instruction
  63. BAD_TRAP; ! 03 priveleged_instruction
  64. BAD_TRAP; ! 04 fp_disabled
  65. TRAP(_window_overflow); ! 05 window_overflow
  66. TRAP(_window_underflow); ! 06 window_underflow
  67. BAD_TRAP; ! 07 Memory Address Not Aligned
  68. BAD_TRAP; ! 08 Floating Point Exception
  69. BAD_TRAP; ! 09 Data Miss Exception
  70. BAD_TRAP; ! 0a Tagged Instruction Ovrflw
  71. BAD_TRAP; ! 0b Watchpoint Detected
  72. BAD_TRAP; ! 0c
  73. BAD_TRAP; ! 0d
  74. BAD_TRAP; ! 0e
  75. BAD_TRAP; ! 0f
  76. BAD_TRAP; ! 10
  77. TRAPI(1); ! 11 IRQ level 1
  78. TRAPI(2); ! 12 IRQ level 2
  79. TRAPI(3); ! 13 IRQ level 3
  80. TRAPI(4); ! 14 IRQ level 4
  81. TRAPI(5); ! 15 IRQ level 5
  82. TRAPI(6); ! 16 IRQ level 6
  83. TRAPI(7); ! 17 IRQ level 7
  84. TRAPI(8); ! 18 IRQ level 8
  85. TRAPI(9); ! 19 IRQ level 9
  86. TRAPI(10); ! 1a IRQ level 10
  87. TRAPI(11); ! 1b IRQ level 11
  88. TRAPI(12); ! 1c IRQ level 12
  89. TRAPI(13); ! 1d IRQ level 13
  90. TRAPI(14); ! 1e IRQ level 14
  91. TRAP(_nmi_trap); ! 1f IRQ level 15 /
  92. ! NMI (non maskable interrupt)
  93. BAD_TRAP; ! 20 r_register_access_error
  94. BAD_TRAP; ! 21 instruction access error
  95. BAD_TRAP; ! 22
  96. BAD_TRAP; ! 23
  97. BAD_TRAP; ! 24 co-processor disabled
  98. BAD_TRAP; ! 25 uniplemented FLUSH
  99. BAD_TRAP; ! 26
  100. BAD_TRAP; ! 27
  101. BAD_TRAP; ! 28 co-processor exception
  102. BAD_TRAP; ! 29 data access error
  103. BAD_TRAP; ! 2a division by zero
  104. BAD_TRAP; ! 2b data store error
  105. BAD_TRAP; ! 2c data access MMU miss
  106. BAD_TRAP; ! 2d
  107. BAD_TRAP; ! 2e
  108. BAD_TRAP; ! 2f
  109. BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 30-33
  110. BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 34-37
  111. BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 38-3b
  112. BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 3c-3f
  113. BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 40-43
  114. BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 44-47
  115. BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 48-4b
  116. BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 4c-4f
  117. BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 50-53
  118. BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 54-57
  119. BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 58-5b
  120. BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 5c-5f
  121. /* implementaion dependent */
  122. BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 60-63
  123. BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 64-67
  124. BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 68-6b
  125. BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 6c-6f
  126. BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 70-73
  127. BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 74-77
  128. BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 78-7b
  129. BAD_TRAP; BAD_TRAP; BAD_TRAP; BAD_TRAP; ! 7c-7f
  130. /* Software traps, not handled */
  131. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! 80-83
  132. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! 84-87
  133. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! 88-8b
  134. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! 8c-8f
  135. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! 90-93
  136. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! 94-97
  137. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! 98-9b
  138. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! 9c-9f
  139. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! a0-a3
  140. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! a4-a7
  141. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! a8-ab
  142. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! ac-af
  143. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! b0-b3
  144. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! b4-b7
  145. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! b8-bb
  146. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! bc-bf
  147. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! c0-c3
  148. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! c4-c7
  149. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! c8-cb
  150. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! cc-cf
  151. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! d0-d3
  152. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! d4-d7
  153. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! d8-db
  154. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! dc-df
  155. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! e0-e3
  156. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! e4-e7
  157. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! e8-eb
  158. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! ec-ef
  159. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! f0-f3
  160. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! f4-f7
  161. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! f8-fb
  162. SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; SOFT_TRAP; ! fc-ff
  163. /*
  164. * Version string
  165. */
  166. .data
  167. .globl version_string
  168. version_string:
  169. .ascii U_BOOT_VERSION_STRING, "\0"
  170. .section ".text"
  171. .align 4
  172. _hardreset:
  173. 1000:
  174. flush
  175. nop
  176. nop
  177. nop
  178. /* Init Cache */
  179. set (LEON2_PREGS+LEON_REG_CACHECTRL_OFFSET), %g1
  180. set 0x0081000f, %g2
  181. st %g2, [%g1]
  182. mov %g0, %y
  183. clr %g1
  184. clr %g2
  185. clr %g3
  186. clr %g4
  187. clr %g5
  188. clr %g6
  189. clr %g7
  190. mov %asr17, %g3
  191. and %g3, 0x1f, %g3
  192. clear_window:
  193. mov %g0, %l0
  194. mov %g0, %l1
  195. mov %g0, %l2
  196. mov %g0, %l3
  197. mov %g0, %l4
  198. mov %g0, %l5
  199. mov %g0, %l6
  200. mov %g0, %l7
  201. mov %g0, %o0
  202. mov %g0, %o1
  203. mov %g0, %o2
  204. mov %g0, %o3
  205. mov %g0, %o4
  206. mov %g0, %o5
  207. mov %g0, %o6
  208. mov %g0, %o7
  209. subcc %g3, 1, %g3
  210. bge clear_window
  211. save
  212. leon2_init:
  213. /* LEON2 Register Base in g1 */
  214. set LEON2_PREGS, %g1
  215. leon2_init_cache:
  216. /* Set Cache control register */
  217. set 0x1000f, %g2
  218. st %g2, [%g1 + 0x14]
  219. leon2_init_clear:
  220. /* Clear LEON2 registers */
  221. st %g0, [%g1 + LEON2_ECTRL]
  222. st %g0, [%g1 + LEON2_IMASK]
  223. st %g0, [%g1 + LEON2_IPEND]
  224. st %g0, [%g1 + LEON2_IFORCE]
  225. st %g0, [%g1 + LEON2_ICLEAR]
  226. st %g0, [%g1 + LEON2_IOREG]
  227. st %g0, [%g1 + LEON2_IODIR]
  228. st %g0, [%g1 + LEON2_IOICONF]
  229. st %g0, [%g1 + LEON2_UCTRL0]
  230. st %g0, [%g1 + LEON2_UCTRL1]
  231. leon2_init_ioport:
  232. /* I/O port initialization */
  233. set 0xaa00, %g2
  234. st %g2, [%g1 + LEON2_IOREG]
  235. leon2_init_mctrl:
  236. /* memory config register 1 */
  237. set CONFIG_SYS_GRLIB_MEMCFG1, %g2
  238. ld [%g1], %g3 !
  239. and %g3, 0x300, %g3
  240. or %g2, %g3, %g2
  241. st %g2, [%g1 + LEON2_MCFG1]
  242. set CONFIG_SYS_GRLIB_MEMCFG2, %g2 ! Load memory config register 2
  243. #if !( defined(TSIM) || !defined(BZIMAGE))
  244. st %g2, [%g1 + LEON2_MCFG2] ! only for prom version, else done by "dumon -i"
  245. #endif
  246. set CONFIG_SYS_GRLIB_MEMCFG3, %g2 ! Init FT register
  247. st %g2, [%g1 + LEON2_ECTRL]
  248. ld [%g1 + LEON2_ECTRL], %g2
  249. srl %g2, 30, %g2
  250. andcc %g2, 3, %g6
  251. bne,a leon2_init_wim
  252. mov %g0, %asr16 ! clear err_reg
  253. leon2_init_wim:
  254. set WIM_INIT, %g3
  255. mov %g3, %wim
  256. leon2_init_psr:
  257. set 0x1000, %g3
  258. mov %psr, %g2
  259. wr %g2, %g3, %psr
  260. nop
  261. nop
  262. nop
  263. leon2_init_stackp:
  264. set CONFIG_SYS_INIT_SP_OFFSET, %fp
  265. andn %fp, 0x0f, %fp
  266. sub %fp, 64, %sp
  267. cpu_init_unreloc:
  268. call cpu_init_f
  269. nop
  270. /* un relocated start address of monitor */
  271. #define TEXT_START _text
  272. /* un relocated end address of monitor */
  273. #define DATA_END __init_end
  274. reloc:
  275. set TEXT_START,%g2
  276. set DATA_END,%g3
  277. set CONFIG_SYS_RELOC_MONITOR_BASE,%g4
  278. reloc_loop:
  279. ldd [%g2],%l0
  280. ldd [%g2+8],%l2
  281. std %l0,[%g4]
  282. std %l2,[%g4+8]
  283. inc 16,%g2
  284. subcc %g3,%g2,%g0
  285. bne reloc_loop
  286. inc 16,%g4
  287. clr %l0
  288. clr %l1
  289. clr %l2
  290. clr %l3
  291. clr %g2
  292. /* register g4 contain address to start
  293. * This means that BSS must be directly after data and code segments
  294. *
  295. * g3 is length of bss = (__bss_end-__bss_start)
  296. *
  297. */
  298. clr_bss:
  299. /* clear bss area (the relocated) */
  300. set __bss_start,%g2
  301. set __bss_end,%g3
  302. sub %g3,%g2,%g3
  303. add %g3,%g4,%g3
  304. clr %g1 /* std %g0 uses g0 and g1 */
  305. /* clearing 16byte a time ==> linker script need to align to 16 byte offset */
  306. clr_bss_16:
  307. std %g0,[%g4]
  308. std %g0,[%g4+8]
  309. inc 16,%g4
  310. cmp %g3,%g4
  311. bne clr_bss_16
  312. nop
  313. /* add offsets to GOT table */
  314. fixup_got:
  315. set __got_start,%g4
  316. set __got_end,%g3
  317. /*
  318. * new got offset = (old GOT-PTR (read with ld) -
  319. * CONFIG_SYS_RELOC_MONITOR_BASE(from define) ) +
  320. * Destination Address (from define)
  321. */
  322. set CONFIG_SYS_RELOC_MONITOR_BASE,%g2
  323. set TEXT_START, %g1
  324. add %g4,%g2,%g4
  325. sub %g4,%g1,%g4
  326. add %g3,%g2,%g3
  327. sub %g3,%g1,%g3
  328. sub %g2,%g1,%g2 ! prepare register with (new base address) -
  329. ! (old base address)
  330. got_loop:
  331. ld [%g4],%l0 ! load old GOT-PTR
  332. add %l0,%g2,%l0 ! increase with (new base address) -
  333. ! (old base)
  334. st %l0,[%g4]
  335. inc 4,%g4
  336. cmp %g3,%g4
  337. bne got_loop
  338. nop
  339. prom_relocate:
  340. set __prom_start, %g2
  341. set __prom_end, %g3
  342. set CONFIG_SYS_PROM_OFFSET, %g4
  343. prom_relocate_loop:
  344. ldd [%g2],%l0
  345. ldd [%g2+8],%l2
  346. std %l0,[%g4]
  347. std %l2,[%g4+8]
  348. inc 16,%g2
  349. subcc %g3,%g2,%g0
  350. bne prom_relocate_loop
  351. inc 16,%g4
  352. /* Trap table has been moved, lets tell CPU about
  353. * the new trap table address
  354. */
  355. set CONFIG_SYS_RELOC_MONITOR_BASE, %g2
  356. wr %g0, %g2, %tbr
  357. /* call relocate*/
  358. nop
  359. /* Call relocated init functions */
  360. jump:
  361. set cpu_init_f2,%o1
  362. set CONFIG_SYS_RELOC_MONITOR_BASE,%o2
  363. add %o1,%o2,%o1
  364. sub %o1,%g1,%o1
  365. call %o1
  366. clr %o0
  367. set board_init_f,%o1
  368. set CONFIG_SYS_RELOC_MONITOR_BASE,%o2
  369. add %o1,%o2,%o1
  370. sub %o1,%g1,%o1
  371. call %o1
  372. clr %o0
  373. dead: ta 0 ! if call returns...
  374. nop
  375. /* Interrupt handler caller,
  376. * reg L7: interrupt number
  377. * reg L0: psr after interrupt
  378. * reg L1: PC
  379. * reg L2: next PC
  380. * reg L3: wim
  381. */
  382. _irq_entry:
  383. SAVE_ALL
  384. or %l0, PSR_PIL, %g2
  385. wr %g2, 0x0, %psr
  386. WRITE_PAUSE
  387. wr %g2, PSR_ET, %psr
  388. WRITE_PAUSE
  389. mov %l7, %o0 ! irq level
  390. set handler_irq, %o1
  391. set (CONFIG_SYS_RELOC_MONITOR_BASE-CONFIG_SYS_TEXT_BASE), %o2
  392. add %o1, %o2, %o1
  393. call %o1
  394. add %sp, SF_REGS_SZ, %o1 ! pt_regs ptr
  395. or %l0, PSR_PIL, %g2 ! restore PIL after handler_irq
  396. wr %g2, PSR_ET, %psr ! keep ET up
  397. WRITE_PAUSE
  398. RESTORE_ALL
  399. !Window overflow trap handler.
  400. .global _window_overflow
  401. _window_overflow:
  402. mov %wim, %l3 ! Calculate next WIM
  403. mov %g1, %l7
  404. srl %l3, 1, %g1
  405. sll %l3, (CONFIG_SYS_SPARC_NWINDOWS-1) , %l4
  406. or %l4, %g1, %g1
  407. save ! Get into window to be saved.
  408. mov %g1, %wim
  409. nop;
  410. nop;
  411. nop
  412. st %l0, [%sp + 0];
  413. st %l1, [%sp + 4];
  414. st %l2, [%sp + 8];
  415. st %l3, [%sp + 12];
  416. st %l4, [%sp + 16];
  417. st %l5, [%sp + 20];
  418. st %l6, [%sp + 24];
  419. st %l7, [%sp + 28];
  420. st %i0, [%sp + 32];
  421. st %i1, [%sp + 36];
  422. st %i2, [%sp + 40];
  423. st %i3, [%sp + 44];
  424. st %i4, [%sp + 48];
  425. st %i5, [%sp + 52];
  426. st %i6, [%sp + 56];
  427. st %i7, [%sp + 60];
  428. restore ! Go back to trap window.
  429. mov %l7, %g1
  430. jmp %l1 ! Re-execute save.
  431. rett %l2
  432. /* Window underflow trap handler. */
  433. .global _window_underflow
  434. _window_underflow:
  435. mov %wim, %l3 ! Calculate next WIM
  436. sll %l3, 1, %l4
  437. srl %l3, (CONFIG_SYS_SPARC_NWINDOWS-1), %l5
  438. or %l5, %l4, %l5
  439. mov %l5, %wim
  440. nop; nop; nop
  441. restore ! Two restores to get into the
  442. restore ! window to restore
  443. ld [%sp + 0], %l0; ! Restore window from the stack
  444. ld [%sp + 4], %l1;
  445. ld [%sp + 8], %l2;
  446. ld [%sp + 12], %l3;
  447. ld [%sp + 16], %l4;
  448. ld [%sp + 20], %l5;
  449. ld [%sp + 24], %l6;
  450. ld [%sp + 28], %l7;
  451. ld [%sp + 32], %i0;
  452. ld [%sp + 36], %i1;
  453. ld [%sp + 40], %i2;
  454. ld [%sp + 44], %i3;
  455. ld [%sp + 48], %i4;
  456. ld [%sp + 52], %i5;
  457. ld [%sp + 56], %i6;
  458. ld [%sp + 60], %i7;
  459. save ! Get back to the trap window.
  460. save
  461. jmp %l1 ! Re-execute restore.
  462. rett %l2
  463. retl
  464. _nmi_trap:
  465. nop
  466. jmp %l1
  467. rett %l2
  468. _hwerr:
  469. ta 0
  470. nop
  471. nop
  472. b _hwerr ! loop infinite
  473. nop
  474. /* Registers to not touch at all. */
  475. #define t_psr l0 /* Set by caller */
  476. #define t_pc l1 /* Set by caller */
  477. #define t_npc l2 /* Set by caller */
  478. #define t_wim l3 /* Set by caller */
  479. #define t_twinmask l4 /* Set at beginning of this entry routine. */
  480. #define t_kstack l5 /* Set right before pt_regs frame is built */
  481. #define t_retpc l6 /* If you change this, change winmacro.h header file */
  482. #define t_systable l7 /* Never touch this, could be the syscall table ptr. */
  483. #define curptr g6 /* Set after pt_regs frame is built */
  484. trap_setup:
  485. /* build a pt_regs trap frame. */
  486. sub %fp, (SF_REGS_SZ + PT_REGS_SZ), %t_kstack
  487. PT_STORE_ALL(t_kstack, t_psr, t_pc, t_npc, g2)
  488. /* See if we are in the trap window. */
  489. mov 1, %t_twinmask
  490. sll %t_twinmask, %t_psr, %t_twinmask ! t_twinmask = (1 << psr)
  491. andcc %t_twinmask, %t_wim, %g0
  492. beq 1f ! in trap window, clean up
  493. nop
  494. /*-------------------------------------------------
  495. * Spill , adjust %wim and go.
  496. */
  497. srl %t_wim, 0x1, %g2 ! begin computation of new %wim
  498. set (CONFIG_SYS_SPARC_NWINDOWS-1), %g3 !NWINDOWS-1
  499. sll %t_wim, %g3, %t_wim ! NWINDOWS-1
  500. or %t_wim, %g2, %g2
  501. and %g2, 0xff, %g2
  502. save %g0, %g0, %g0 ! get in window to be saved
  503. /* Set new %wim value */
  504. wr %g2, 0x0, %wim
  505. /* Save the kernel window onto the corresponding stack. */
  506. RW_STORE(sp)
  507. restore %g0, %g0, %g0
  508. /*-------------------------------------------------*/
  509. 1:
  510. /* Trap from kernel with a window available.
  511. * Just do it...
  512. */
  513. jmpl %t_retpc + 0x8, %g0 ! return to caller
  514. mov %t_kstack, %sp ! jump onto new stack
  515. #define twin_tmp1 l4
  516. #define glob_tmp g4
  517. #define curptr g6
  518. ret_trap_entry:
  519. wr %t_psr, 0x0, %psr ! enable nesting again, clear ET
  520. /* Will the rett land us in the invalid window? */
  521. mov 2, %g1
  522. sll %g1, %t_psr, %g1
  523. set CONFIG_SYS_SPARC_NWINDOWS, %g2 !NWINDOWS
  524. srl %g1, %g2, %g2
  525. or %g1, %g2, %g1
  526. rd %wim, %g2
  527. andcc %g2, %g1, %g0
  528. be 1f ! Nope, just return from the trap
  529. sll %g2, 0x1, %g1
  530. /* We have to grab a window before returning. */
  531. set (CONFIG_SYS_SPARC_NWINDOWS-1), %g3 !NWINDOWS-1
  532. srl %g2, %g3, %g2
  533. or %g1, %g2, %g1
  534. and %g1, 0xff, %g1
  535. wr %g1, 0x0, %wim
  536. /* Grrr, make sure we load from the right %sp... */
  537. PT_LOAD_ALL(sp, t_psr, t_pc, t_npc, g1)
  538. restore %g0, %g0, %g0
  539. RW_LOAD(sp)
  540. b 2f
  541. save %g0, %g0, %g0
  542. /* Reload the entire frame in case this is from a
  543. * kernel system call or whatever...
  544. */
  545. 1:
  546. PT_LOAD_ALL(sp, t_psr, t_pc, t_npc, g1)
  547. 2:
  548. wr %t_psr, 0x0, %psr
  549. nop;
  550. nop;
  551. nop
  552. jmp %t_pc
  553. rett %t_npc
  554. /* This is called from relocated C-code.
  555. * It resets the system by jumping to _start
  556. */
  557. _reset_reloc:
  558. set start, %l0
  559. call %l0
  560. nop