4 * Copyright (C) 2001, 2002, 2007, 2009, 2012 Imagination Technologies.
6 * This program is free software; you can redistribute it and/or modify it under
7 * the terms of the GNU General Public License version 2 as published by the
8 * Free Software Foundation.
10 * Asyncronous trigger handling including exceptions
14 #include <asm/metag_regs.h>
18 /* define these for now while doing inital conversion to GAS
19 will fix properly later */
21 /* Signal identifiers always have the TBID_SIGNAL_BIT set and contain the
22 following related bit-fields */
23 #define TBID_SIGNUM_S 2
28 /* Ax.4 is saved in TBICTX */
31 /* Ax.4 is NOT saved in TBICTX */
35 /* Size of the TBICTX structure */
36 #define TBICTX_BYTES ((TBICTX_AX_REGS*8)+TBICTX_AX)
41 /* Jump straight into the boot ROM version of this code */
42 #define CODE_USES_BOOTROM
47 /* Define space needed for CATCH buffer state in traditional units */
48 #define CATCH_ENTRIES 5
49 #define CATCH_ENTRY_BYTES 16
51 #ifndef CODE_USES_BOOTROM
52 #define A0GblIStP A0.15 /* PTBICTX for current thread in PRIV system */
53 #define A1GblIGbP A1.15 /* Interrupt A1GbP value in PRIV system */
57 * TBIRES __TBIASyncTrigger( TBIRES State )
61 .global ___TBIASyncTrigger
62 .type ___TBIASyncTrigger,function
64 #ifdef CODE_USES_BOOTROM
65 MOVT D0Re0,#HI(LINCORE_BASE)
68 MOV D0FrT,A0FrP /* Boing entry sequence */
70 SETL [A0StP++],D0FrT,D1RtP
71 MOV D0Re0,PCX /* Check for repeat call */
72 MOVT D0FrT,#HI(___TBIBoingRTI+4)
73 ADD D0FrT,D0FrT,#LO(___TBIBoingRTI+4)
75 BEQ ___TBIBoingExit /* Already set up - come out */
76 ADD D1Ar1,D1Ar1,#7 /* PRIV system stack here */
77 MOV A0.2,A0StP /* else push context here */
78 MOVS D0Re0,D0Ar2 /* Return in user mode? */
79 ANDMB D1Ar1,D1Ar1,#0xfff8 /* align priv stack to 64-bit */
80 MOV D1Re0,D1Ar1 /* and set result to arg */
81 MOVMI A0.2,D1Ar1 /* use priv stack if PRIV set */
83 * Generate an initial TBICTX to return to our own current call context
85 MOVT D1Ar5,#HI(___TBIBoingExit) /* Go here to return */
86 ADD D1Ar5,D1Ar5,#LO(___TBIBoingExit)
87 ADD A0.3,A0.2,#TBICTX_DX /* DX Save area */
88 ANDT D0Ar2,D0Ar2,#TBICTX_PRIV_BIT /* Extract PRIV bit */
89 MOVT D0Ar6,#TBICTX_SOFT_BIT /* Only soft thread state */
90 ADD D0Ar6,D0Ar6,D0Ar2 /* Add in PRIV bit if requested */
91 SETL [A0.2],D0Ar6,D1Ar5 /* Push header fields */
92 ADD D0FrT,A0.2,#TBICTX_AX /* Address AX save area */
93 MSETL [A0.3],D0Re0,D0Ar6,D0Ar4,D0Ar2,D0FrT,D0.5,D0.6,D0.7
96 SETL [A0.3++],D0Ar6,D1Ar5 /* Zero CT register states */
97 SETL [A0.3++],D0Ar6,D1Ar5
98 MSETL [D0FrT],A0StP,A0FrP,A0.2,A0.3 A0_4 /* Save AX regs */
99 MOV A0FrP,A0.2 /* Restore me! */
101 .size ___TBIASyncTrigger,.-___TBIASyncTrigger
104 * Optimised return to handler for META Core
107 RTH /* Go to background level */
108 MOVT A0.2, #HI($Lpcx_target)
109 ADD A0.2,A0.2,#LO($Lpcx_target)
110 MOV PCX,A0.2 /* Setup PCX for interrupts */
111 MOV PC,D1Re0 /* Jump to handler */
113 * This is where the code below needs to jump to wait for outermost interrupt
114 * event in a non-privilege mode system (single shared interrupt stack).
117 MGETL A0StP,A0FrP,A0.2,A0.3 A0_4,[D1Re0] /* Restore AX regs */
118 MOV TXSTATUS,D0Re0 /* Restore flags */
119 GETL D0Re0,D1Re0,[D1Re0+#TBICTX_DX-TBICTX_BYTES]
121 RTI /* Wait for interrupt */
124 * Save initial interrupt state on current stack
126 SETL [A0StP+#TBICTX_DX],D0Re0,D1Re0 /* Save key registers */
127 ADD D1Re0,A0StP,#TBICTX_AX /* Address AX save area */
128 MOV D0Re0,TXSTATUS /* Read TXSTATUS into D0Re0 */
129 MOV TXSTATUS,#0 /* Clear TXSTATUS */
130 MSETL [D1Re0],A0StP,A0FrP,A0.2,A0.3 A0_4 /* Save AX critical regs */
132 * Register state at this point is-
134 * D0Re0 - Old TXSTATUS with PRIV and CBUF bits set if appropriate
135 * A0StP - Is call stack frame and base of TBICTX being generated
136 * A1GbP - Is valid static access link
139 LOCK0 /* Make sure we have no locks! */
140 ADD A1.2,A0StP,#TBICTX_DX+(8*1) /* Address DX.1 save area */
141 MOV A0FrP,A0StP /* Setup frame pointer */
142 MSETL [A1.2],D0Ar6,D0Ar4,D0Ar2,D0FrT,D0.5,D0.6,D0.7
143 MOV D0Ar4,TXRPT /* Save critical CT regs */
145 MOV D1Ar1,TXDIVTIME /* Calc catch buffer pSrc */
147 MOV TXMODE,#0 /* Clear TXMODE */
148 #ifdef TXDIVTIME_RPDIRTY_BIT
149 TSTT D1Ar1,#HI(TXDIVTIME_RPDIRTY_BIT)/* NZ = RPDIRTY */
150 MOVT D0Ar6,#TBICTX_CBRP_BIT
151 ORNZ D0Re0,D0Re0,D0Ar6 /* Set CBRP if RPDIRTY set */
153 MSETL [A1.2],D0Ar4,D0Ar2 /* Save CT regs state */
154 MOV D0Ar2,D0Re0 /* Copy TXSTATUS */
155 ANDMT D0Ar2,D0Ar2,#TBICTX_CBUF_BIT+TBICTX_CBRP_BIT
157 MOVT D1Ar1,#TBICTX_FPAC_BIT /* Copy FPActive into FPAC */
158 TSTT D0Re0,#HI(TXSTATUS_FPACTIVE_BIT)
159 ORNZ D0Ar2,D0Ar2,D1Ar1
161 MOV D1Ar1,PCX /* Read CurrPC */
162 ORT D0Ar2,D0Ar2,#TBICTX_CRIT_BIT /* SaveMask + CRIT bit */
163 SETL [A0FrP+#TBICTX_Flags],D0Ar2,D1Ar1 /* Set pCtx header fields */
165 * Completed context save, now we need to make a call to an interrupt handler
167 * D0Re0 - holds PRIV, WAIT, CBUF flags, HALT reason if appropriate
168 * A0FrP - interrupt stack frame and base of TBICTX being generated
169 * A0StP - same as A0FrP
172 /* Reserve space for TBICTX and CBUF */
173 ADD A0StP,A0StP,#TBICTX_BYTES+(CATCH_ENTRY_BYTES*CATCH_ENTRIES)
174 MOV D0Ar4,TXSTATI /* Read the Triggers data */
175 MOV D1Ar3,TXDIVTIME /* Read IRQEnc bits */
176 MOV D0Ar2,D0Re0 /* Copy PRIV and WAIT flags */
177 ANDT D0Ar2,D0Ar2,#TBICTX_PRIV_BIT+TBICTX_WAIT_BIT+TBICTX_CBUF_BIT
179 MOVT D1Ar5,#TBICTX_FPAC_BIT /* Copy FPActive into FPAC */
180 TSTT D0Re0,#HI(TXSTATUS_FPACTIVE_BIT)
181 ORNZ D0Ar2,D0Ar2,D1Ar5
183 ANDT D1Ar3,D1Ar3,#HI(TXDIVTIME_IRQENC_BITS)
184 LSR D1Ar3,D1Ar3,#TXDIVTIME_IRQENC_S
185 AND TXSTATI,D0Ar4,#TXSTATI_BGNDHALT_BIT/* Ack any HALT seen */
186 ANDS D0Ar4,D0Ar4,#0xFFFF-TXSTATI_BGNDHALT_BIT /* Only seen HALT? */
187 ORT D0Ar2,D0Ar2,#TBICTX_CRIT_BIT /* Set CRIT */
189 MOVT A1LbP,#HI(___pTBIs)
190 ADD A1LbP,A1LbP,#LO(___pTBIs)
191 GETL D1Ar5,D0Ar6,[A1LbP] /* D0Ar6 = ___pTBIs[1] */
194 * For BOOTROM support ___pTBIs must be allocated at offset 0 vs A1GbP
196 GETL D1Ar5,D0Ar6,[A1GbP] /* D0Ar6 = ___pTBIs[1] */
198 BZ ___TBIBoingHalt /* Yes: Service HALT */
200 * Encode interrupt as signal vector, strip away same/lower TXMASKI bits
202 MOV D1Ar1,#1 /* Generate mask for this bit */
203 MOV D0Re0,TXMASKI /* Get interrupt mask */
204 LSL TXSTATI,D1Ar1,D1Ar3 /* Acknowledge trigger */
205 AND TXMASKI,D0Re0,#TXSTATI_BGNDHALT_BIT /* Only allow HALTs */
206 OR D0Ar2,D0Ar2,D0Re0 /* Set TBIRES.Sig.TrigMask */
207 ADD D1Ar3,D1Ar3,#TBID_SIGNUM_TRT /* Offset into interrupt sigs */
208 LSL D0Re0,D1Ar3,#TBID_SIGNUM_S /* Generate offset from SigNum */
210 * This is a key moment we are about to call the handler, register state is
213 * D0Re0 - Handler vector (SigNum<<TBID_SIGNUM_S)
214 * D0Ar2 - TXMASKI:TBICTX_CRIT_BIT with optional CBUF and PRIV bits
216 * D0Ar4 - State read from TXSTATI
217 * D1Ar5 - Inst for SWITCH trigger case only, otherwise undefined
221 ADD D0Re0,D0Re0,#TBI_fnSigs /* Offset into signal table */
222 GETD D1Re0,[D0Ar6+D0Re0] /* Get address for Handler */
224 * Call handler at interrupt level, when it returns simply resume execution
225 * of state indicated by D1Re0.
227 MOV D1Ar1,A0FrP /* Pass in pCtx */
228 CALLR D1RtP,___TBIBoingRTH /* Use RTH to invoke handler */
231 * Perform critical state restore and execute background thread.
233 * A0FrP - is pointer to TBICTX structure to resume
234 * D0Re0 - contains additional TXMASKI triggers
245 RTH /* Go to interrupt level */
246 MOV D0Ar4,TXMASKI /* Read TXMASKI */
247 OR TXMASKI,D0Ar4,D0Re0 /* -Write-Modify TXMASKI */
248 GETL D0Re0,D1Re0,[A0FrP+#TBICTX_Flags]/* Get Flags:SaveMask, CurrPC */
249 MOV A0StP,A0FrP /* Position stack pointer */
250 MOV D0Ar2,TXPOLLI /* Read pending triggers */
251 MOV PCX,D1Re0 /* Set resumption PC */
252 TST D0Ar2,#0xFFFF /* Any pending triggers? */
253 BNZ ___TBIBoingWait /* Yes: Go for triggers */
254 TSTT D0Re0,#TBICTX_WAIT_BIT /* Do we WAIT anyway? */
255 BNZ ___TBIBoingWait /* Yes: Go for triggers */
256 LSLS D1Ar5,D0Re0,#1 /* Test XCBF (MI) & PRIV (CS)? */
257 ADD D1Re0,A0FrP,#TBICTX_CurrRPT /* Address CT save area */
258 ADD A0StP,A0FrP,#TBICTX_DX+(8*1) /* Address DX.1 save area */
259 MGETL A0.2,A0.3,[D1Re0] /* Get CT reg states */
260 MOV D1Ar3,A1.3 /* Copy old TXDIVTIME */
261 BPL ___TBIResCrit /* No: Skip logic */
262 ADD D0Ar4,A0FrP,#TBICTX_BYTES /* Source is after TBICTX */
263 ANDST D1Ar3,D1Ar3,#HI(TXDIVTIME_RPMASK_BITS)/* !Z if RPDIRTY */
264 MGETL D0.5,D0.6,[D0Ar4] /* Read Catch state */
265 MOV TXCATCH0,D0.5 /* Restore TXCATCHn */
271 LSRS D1Ar3,D1Ar3,#TXDIVTIME_RPMASK_S+1 /* 2nd RPMASK bit -> bit 0 */
272 ADD RA,D0Ar4,#(0*8) /* Re-read read pipeline */
273 ADDNZ RA,D0Ar4,D0Ar2 /* If Bit 0 set issue RA */
274 LSRS D1Ar3,D1Ar3,#2 /* Bit 1 -> C, Bit 2 -> Bit 0 */
276 ADDCS RA,D0Ar4,D0Ar2 /* If C issue RA */
278 ADDNZ RA,D0Ar4,D0Ar2 /* If Bit 0 set issue RA */
279 LSRS D1Ar3,D1Ar3,#2 /* Bit 1 -> C, Bit 2 -> Bit 0 */
281 ADDCS RA,D0Ar4,D0Ar2 /* If C issue RA */
283 ADDNZ RA,D0Ar4,D0Ar2 /* If Bit 0 set issue RA */
284 MOV TXDIVTIME,A1.3 /* Set RPDIRTY again */
286 LSLS D1Ar5,D0Re0,#1 /* Test XCBF (MI) & PRIV (CS)? */
288 ANDT D1Ar5,D1Ar5,#(TBICTX_FPAC_BIT*2)
289 LSL D0Ar6,D1Ar5,#3 /* Convert FPAC into FPACTIVE */
291 ANDMT D0Re0,D0Re0,#TBICTX_CBUF_BIT /* Keep CBUF bit from SaveMask */
293 OR D0Re0,D0Re0,D0Ar6 /* Combine FPACTIVE with others */
295 MGETL D0Ar6,D0Ar4,D0Ar2,D0FrT,D0.5,D0.6,D0.7,[A0StP] /* Restore DX */
296 MOV TXRPT,A0.2 /* Restore CT regs */
299 BCC ___TBIBoingPCX /* Do non-PRIV wait! */
300 MOV A1GblIGbP,A1GbP /* Save A1GbP too */
301 MGETL A0StP,A0FrP,A0.2,A0.3 A0_4,[D1Re0] /* Restore AX regs */
303 * Wait for the first interrupt/exception trigger in a privilege mode system
304 * (interrupt stack area for current TASK to be pointed to by A0GblIStP
305 * or per_cpu__stack_save[hwthread_id]).
307 MOV TXSTATUS,D0Re0 /* Restore flags */
308 MOV D0Re0,TXPRIVEXT /* Set TXPRIVEXT_TXTOGGLEI_BIT */
309 SUB D1Re0,D1Re0,#TBICTX_BYTES /* TBICTX is top of int stack */
310 #ifdef TBX_PERCPU_SP_SAVE
312 MOV D1Ar3,TXENABLE /* Which thread are we? */
313 AND D1Ar3,D1Ar3,#TXENABLE_THREAD_BITS
314 LSR D1Ar3,D1Ar3,#TXENABLE_THREAD_S-2
315 ADDT D1Ar3,D1Ar3,#HI(_per_cpu__stack_save)
316 ADD D1Ar3,D1Ar3,#LO(_per_cpu__stack_save)
322 OR D0Re0,D0Re0,#TXPRIVEXT_TXTOGGLEI_BIT
323 MOV TXPRIVEXT,D0Re0 /* Cannot set TXPRIVEXT if !priv */
324 GETL D0Re0,D1Re0,[D1Re0+#TBICTX_DX]
325 RTI /* Wait for interrupt */
327 * Save initial interrupt state on A0GblIStP, switch to A0GblIStP if
328 * BOOTROM code, save and switch to [A1GbP] otherwise.
331 #ifdef TBX_PERCPU_SP_SAVE
332 SWAP D1Ar3,A1GbP /* Get PRIV stack base */
333 MOV D1Ar3,TXENABLE /* Which thread are we? */
334 AND D1Ar3,D1Ar3,#TXENABLE_THREAD_BITS
335 LSR D1Ar3,D1Ar3,#TXENABLE_THREAD_S-2
336 ADDT D1Ar3,D1Ar3,#HI(_per_cpu__stack_save)
337 ADD D1Ar3,D1Ar3,#LO(_per_cpu__stack_save)
340 SWAP D1Ar3,A0GblIStP /* Get PRIV stack base */
342 SETL [D1Ar3+#TBICTX_DX],D0Re0,D1Re0 /* Save key registers */
343 MOV D0Re0,TXPRIVEXT /* Clear TXPRIVEXT_TXTOGGLEI_BIT */
344 ADD D1Re0,D1Ar3,#TBICTX_AX /* Address AX save area */
345 ANDMB D0Re0,D0Re0,#0xFFFF-TXPRIVEXT_TXTOGGLEI_BIT
346 MOV TXPRIVEXT,D0Re0 /* Cannot set TXPRIVEXT if !priv */
347 MOV D0Re0,TXSTATUS /* Read TXSTATUS into D0Re0 */
348 MOV TXSTATUS,#0 /* Clear TXSTATUS */
349 MSETL [D1Re0],A0StP,A0FrP,A0.2,A0.3 A0_4 /* Save AX critical regs */
350 MOV A0StP,D1Ar3 /* Switch stacks */
351 #ifdef TBX_PERCPU_SP_SAVE
352 MOV D1Ar3,A1GbP /* Get D1Ar2 back */
354 MOV D1Ar3,A0GblIStP /* Get D1Ar2 back */
356 ORT D0Re0,D0Re0,#TBICTX_PRIV_BIT /* Add PRIV to TXSTATUS */
357 MOV A1GbP,A1GblIGbP /* Restore A1GbP */
358 B ___TBIBoing /* Enter common handler code */
360 * At this point we know it's a background HALT case we are handling.
361 * The restored TXSTATUS always needs to have zero in the reason bits.
364 MOV D0Ar4,TXMASKI /* Get interrupt mask */
365 ANDST D0Re0,D0Re0,#HI(TXSTATUS_MAJOR_HALT_BITS+TXSTATUS_MEM_FAULT_BITS)
366 AND TXMASKI,D0Ar4,#TXSTATI_BGNDHALT_BIT /* Only allow HALTs */
367 AND D0Ar4,D0Ar4,#0xFFFF-TXSTATI_BGNDHALT_BIT /* What ints are off? */
368 OR D0Ar2,D0Ar2,D0Ar4 /* Set TBIRES.Sig.TrigMask */
369 MOV D0Ar4,#TXSTATI_BGNDHALT_BIT /* This was the trigger state */
370 LSR D1Ar3,D0Re0,#TXSTATUS_MAJOR_HALT_S
371 MOV D0Re0,#TBID_SIGNUM_XXF<<TBID_SIGNUM_S
372 BNZ ___TBIBoingVec /* Jump to XXF exception handler */
374 * Only the SWITCH cases are left, PCX must be valid
378 TST D1Ar5,#TXPRIVEXT_MINIMON_BIT
379 LSR D1Ar3,D1Ar1,#1 /* Shift needed for MINIM paths (fill stall) */
380 BZ $Lmeta /* If META only, skip */
381 TSTT D1Ar1,#HI(0x00800000)
382 ANDMT D1Ar3,D1Ar3,#HI(0x007FFFFF >> 1)/* Shifted mask for large MINIM */
383 ANDT D1Ar1,D1Ar1,#HI(0xFFE00000) /* Static mask for small MINIM */
384 BZ $Llarge_minim /* If large MINIM */
386 TSTT D1Ar3,#HI(0x00100000 >> 1)
387 ANDMT D1Ar3,D1Ar3,#HI(0x001FFFFF >> 1)/* Correct shifted mask for large MINIM */
388 ADDZ D1Ar1,D1Ar1,D1Ar3 /* If META rgn, add twice to undo LSR #1 */
391 ANDST D1Ar1,D1Ar1,#HI(0xFF800000) /* Correct static mask for small MINIM */
392 /* Z=0 (Cannot place code at NULL) */
394 ADD D1Ar1,D1Ar1,D1Ar3 /* Combine static and shifted parts */
396 GETW D1Ar5,[D1Ar1++] /* META: lo-16, MINIM: lo-16 (all-16 if short) */
397 GETW D1Ar3,[D1Ar1] /* META: hi-16, MINIM: hi-16 (only if long) */
399 XOR D1Re0,D1Re0,#0x4000
400 LSLSNZ D1Re0,D1Re0,#(32-14) /* MINIM: If long C=0, if short C=1 */
401 LSLCC D1Ar3,D1Ar3,#16 /* META/MINIM long: Move hi-16 up */
402 LSLCS D1Ar3,D1Ar5,#16 /* MINIM short: Dup all-16 */
403 ADD D1Ar5,D1Ar5,D1Ar3 /* ALL: Combine both 16-bit parts */
405 GETD D1Ar5,[D1Ar1] /* Read instruction for switch */
407 LSR D1Ar3,D1Ar5,#22 /* Convert into signal number */
408 AND D1Ar3,D1Ar3,#TBID_SIGNUM_SW3-TBID_SIGNUM_SW0
409 LSL D0Re0,D1Ar3,#TBID_SIGNUM_S /* Generate offset from SigNum */
410 B ___TBIBoingVec /* Jump to switch handler */
412 * Exit from TBIASyncTrigger call
415 GETL D0FrT,D1RtP,[A0FrP++] /* Restore state from frame */
416 SUB A0StP,A0FrP,#8 /* Unwind stack */
417 MOV A0FrP,D0FrT /* Last memory read completes */
418 MOV PC,D1RtP /* Return to caller */
419 #endif /* ifdef CODE_USES_BOOTROM */
420 .size ___TBIResume,.-___TBIResume
424 * void __TBIASyncResume( TBIRES State )
428 .global ___TBIASyncResume
429 .type ___TBIASyncResume,function
432 * Perform CRIT|SOFT state restore and execute background thread.
434 MOV D1Ar3,D1Ar1 /* Restore this context */
435 MOV D0Re0,D0Ar2 /* Carry in additional triggers */
436 /* Reserve space for TBICTX */
437 ADD D1Ar3,D1Ar3,#TBICTX_BYTES+(CATCH_ENTRY_BYTES*CATCH_ENTRIES)
438 MOV A0StP,D1Ar3 /* Enter with protection of */
439 MOV A0FrP,D1Ar1 /* TBICTX on our stack */
440 #ifdef CODE_USES_BOOTROM
441 MOVT D1Ar1,#HI(LINCORE_BASE)
446 .size ___TBIASyncResume,.-___TBIASyncResume
447 #endif /* ifndef BOOTROM */