xref: /openbmc/linux/arch/arm/mach-omap2/sleep34xx.S (revision d0b73b48)
1/*
2 * (C) Copyright 2007
3 * Texas Instruments
4 * Karthik Dasu <karthik-dp@ti.com>
5 *
6 * (C) Copyright 2004
7 * Texas Instruments, <www.ti.com>
8 * Richard Woodruff <r-woodruff2@ti.com>
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License as
12 * published by the Free Software Foundation; either version 2 of
13 * the License, or (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR /PURPOSE.  See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
23 * MA 02111-1307 USA
24 */
25#include <linux/linkage.h>
26
27#include <asm/assembler.h>
28
29#include "omap34xx.h"
30#include "iomap.h"
31#include "cm3xxx.h"
32#include "prm3xxx.h"
33#include "sdrc.h"
34#include "sram.h"
35#include "control.h"
36
37/*
38 * Registers access definitions
39 */
40#define SDRC_SCRATCHPAD_SEM_OFFS	0xc
41#define SDRC_SCRATCHPAD_SEM_V	OMAP343X_SCRATCHPAD_REGADDR\
42					(SDRC_SCRATCHPAD_SEM_OFFS)
43#define PM_PREPWSTST_CORE_P	OMAP3430_PRM_BASE + CORE_MOD +\
44					OMAP3430_PM_PREPWSTST
45#define PM_PWSTCTRL_MPU_P	OMAP3430_PRM_BASE + MPU_MOD + OMAP2_PM_PWSTCTRL
46#define CM_IDLEST1_CORE_V	OMAP34XX_CM_REGADDR(CORE_MOD, CM_IDLEST1)
47#define CM_IDLEST_CKGEN_V	OMAP34XX_CM_REGADDR(PLL_MOD, CM_IDLEST)
48#define SRAM_BASE_P		OMAP3_SRAM_PA
49#define CONTROL_STAT		OMAP343X_CTRL_BASE + OMAP343X_CONTROL_STATUS
50#define CONTROL_MEM_RTA_CTRL	(OMAP343X_CTRL_BASE +\
51					OMAP36XX_CONTROL_MEM_RTA_CTRL)
52
53/* Move this as correct place is available */
54#define SCRATCHPAD_MEM_OFFS	0x310
55#define SCRATCHPAD_BASE_P	(OMAP343X_CTRL_BASE +\
56					OMAP343X_CONTROL_MEM_WKUP +\
57					SCRATCHPAD_MEM_OFFS)
58#define SDRC_POWER_V		OMAP34XX_SDRC_REGADDR(SDRC_POWER)
59#define SDRC_SYSCONFIG_P	(OMAP343X_SDRC_BASE + SDRC_SYSCONFIG)
60#define SDRC_MR_0_P		(OMAP343X_SDRC_BASE + SDRC_MR_0)
61#define SDRC_EMR2_0_P		(OMAP343X_SDRC_BASE + SDRC_EMR2_0)
62#define SDRC_MANUAL_0_P		(OMAP343X_SDRC_BASE + SDRC_MANUAL_0)
63#define SDRC_MR_1_P		(OMAP343X_SDRC_BASE + SDRC_MR_1)
64#define SDRC_EMR2_1_P		(OMAP343X_SDRC_BASE + SDRC_EMR2_1)
65#define SDRC_MANUAL_1_P		(OMAP343X_SDRC_BASE + SDRC_MANUAL_1)
66#define SDRC_DLLA_STATUS_V	OMAP34XX_SDRC_REGADDR(SDRC_DLLA_STATUS)
67#define SDRC_DLLA_CTRL_V	OMAP34XX_SDRC_REGADDR(SDRC_DLLA_CTRL)
68
69/*
70 * This file needs be built unconditionally as ARM to interoperate correctly
71 * with non-Thumb-2-capable firmware.
72 */
73	.arm
74
75/*
76 * API functions
77 */
78
79	.text
80/*
81 * L2 cache needs to be toggled for stable OFF mode functionality on 3630.
82 * This function sets up a flag that will allow for this toggling to take
83 * place on 3630. Hopefully some version in the future may not need this.
84 */
85ENTRY(enable_omap3630_toggle_l2_on_restore)
86	stmfd	sp!, {lr}	@ save registers on stack
87	/* Setup so that we will disable and enable l2 */
88	mov	r1, #0x1
89	adrl	r2, l2dis_3630	@ may be too distant for plain adr
90	str	r1, [r2]
91	ldmfd	sp!, {pc}	@ restore regs and return
92ENDPROC(enable_omap3630_toggle_l2_on_restore)
93
94	.text
95/* Function to call rom code to save secure ram context */
96	.align	3
97ENTRY(save_secure_ram_context)
98	stmfd	sp!, {r4 - r11, lr}	@ save registers on stack
99	adr	r3, api_params		@ r3 points to parameters
100	str	r0, [r3,#0x4]		@ r0 has sdram address
101	ldr	r12, high_mask
102	and	r3, r3, r12
103	ldr	r12, sram_phy_addr_mask
104	orr	r3, r3, r12
105	mov	r0, #25			@ set service ID for PPA
106	mov	r12, r0			@ copy secure service ID in r12
107	mov	r1, #0			@ set task id for ROM code in r1
108	mov	r2, #4			@ set some flags in r2, r6
109	mov	r6, #0xff
110	dsb				@ data write barrier
111	dmb				@ data memory barrier
112	smc	#1			@ call SMI monitor (smi #1)
113	nop
114	nop
115	nop
116	nop
117	ldmfd	sp!, {r4 - r11, pc}
118	.align
119sram_phy_addr_mask:
120	.word	SRAM_BASE_P
121high_mask:
122	.word	0xffff
123api_params:
124	.word	0x4, 0x0, 0x0, 0x1, 0x1
125ENDPROC(save_secure_ram_context)
126ENTRY(save_secure_ram_context_sz)
127	.word	. - save_secure_ram_context
128
129/*
130 * ======================
131 * == Idle entry point ==
132 * ======================
133 */
134
135/*
136 * Forces OMAP into idle state
137 *
138 * omap34xx_cpu_suspend() - This bit of code saves the CPU context if needed
139 * and executes the WFI instruction. Calling WFI effectively changes the
140 * power domains states to the desired target power states.
141 *
142 *
143 * Notes:
144 * - only the minimum set of functions gets copied to internal SRAM at boot
145 *   and after wake-up from OFF mode, cf. omap_push_sram_idle. The function
146 *   pointers in SDRAM or SRAM are called depending on the desired low power
147 *   target state.
148 * - when the OMAP wakes up it continues at different execution points
149 *   depending on the low power mode (non-OFF vs OFF modes),
150 *   cf. 'Resume path for xxx mode' comments.
151 */
152	.align	3
153ENTRY(omap34xx_cpu_suspend)
154	stmfd	sp!, {r4 - r11, lr}	@ save registers on stack
155
156	/*
157	 * r0 contains information about saving context:
158	 *   0 - No context lost
159	 *   1 - Only L1 and logic lost
160	 *   2 - Only L2 lost (Even L1 is retained we clean it along with L2)
161	 *   3 - Both L1 and L2 lost and logic lost
162	 */
163
164	/*
165	 * For OFF mode: save context and jump to WFI in SDRAM (omap3_do_wfi)
166	 * For non-OFF modes: jump to the WFI code in SRAM (omap3_do_wfi_sram)
167	 */
168	ldr	r4, omap3_do_wfi_sram_addr
169	ldr	r5, [r4]
170	cmp	r0, #0x0		@ If no context save required,
171	bxeq	r5			@  jump to the WFI code in SRAM
172
173
174	/* Otherwise fall through to the save context code */
175save_context_wfi:
176	/*
177	 * jump out to kernel flush routine
178	 *  - reuse that code is better
179	 *  - it executes in a cached space so is faster than refetch per-block
180	 *  - should be faster and will change with kernel
181	 *  - 'might' have to copy address, load and jump to it
182	 * Flush all data from the L1 data cache before disabling
183	 * SCTLR.C bit.
184	 */
185	ldr	r1, kernel_flush
186	mov	lr, pc
187	bx	r1
188
189	/*
190	 * Clear the SCTLR.C bit to prevent further data cache
191	 * allocation. Clearing SCTLR.C would make all the data accesses
192	 * strongly ordered and would not hit the cache.
193	 */
194	mrc	p15, 0, r0, c1, c0, 0
195	bic	r0, r0, #(1 << 2)	@ Disable the C bit
196	mcr	p15, 0, r0, c1, c0, 0
197	isb
198
199	/*
200	 * Invalidate L1 data cache. Even though only invalidate is
201	 * necessary exported flush API is used here. Doing clean
202	 * on already clean cache would be almost NOP.
203	 */
204	ldr	r1, kernel_flush
205	blx	r1
206	/*
207	 * The kernel doesn't interwork: v7_flush_dcache_all in particluar will
208	 * always return in Thumb state when CONFIG_THUMB2_KERNEL is enabled.
209	 * This sequence switches back to ARM.  Note that .align may insert a
210	 * nop: bx pc needs to be word-aligned in order to work.
211	 */
212 THUMB(	.thumb		)
213 THUMB(	.align		)
214 THUMB(	bx	pc	)
215 THUMB(	nop		)
216	.arm
217
218	b	omap3_do_wfi
219
220/*
221 * Local variables
222 */
223omap3_do_wfi_sram_addr:
224	.word omap3_do_wfi_sram
225kernel_flush:
226	.word v7_flush_dcache_all
227
228/* ===================================
229 * == WFI instruction => Enter idle ==
230 * ===================================
231 */
232
233/*
234 * Do WFI instruction
235 * Includes the resume path for non-OFF modes
236 *
237 * This code gets copied to internal SRAM and is accessible
238 * from both SDRAM and SRAM:
239 * - executed from SRAM for non-off modes (omap3_do_wfi_sram),
240 * - executed from SDRAM for OFF mode (omap3_do_wfi).
241 */
242	.align	3
243ENTRY(omap3_do_wfi)
244	ldr	r4, sdrc_power		@ read the SDRC_POWER register
245	ldr	r5, [r4]		@ read the contents of SDRC_POWER
246	orr	r5, r5, #0x40		@ enable self refresh on idle req
247	str	r5, [r4]		@ write back to SDRC_POWER register
248
249	/* Data memory barrier and Data sync barrier */
250	dsb
251	dmb
252
253/*
254 * ===================================
255 * == WFI instruction => Enter idle ==
256 * ===================================
257 */
258	wfi				@ wait for interrupt
259
260/*
261 * ===================================
262 * == Resume path for non-OFF modes ==
263 * ===================================
264 */
265	nop
266	nop
267	nop
268	nop
269	nop
270	nop
271	nop
272	nop
273	nop
274	nop
275
276/*
277 * This function implements the erratum ID i581 WA:
278 *  SDRC state restore before accessing the SDRAM
279 *
280 * Only used at return from non-OFF mode. For OFF
281 * mode the ROM code configures the SDRC and
282 * the DPLL before calling the restore code directly
283 * from DDR.
284 */
285
286/* Make sure SDRC accesses are ok */
287wait_sdrc_ok:
288
289/* DPLL3 must be locked before accessing the SDRC. Maybe the HW ensures this */
290	ldr	r4, cm_idlest_ckgen
291wait_dpll3_lock:
292	ldr	r5, [r4]
293	tst	r5, #1
294	beq	wait_dpll3_lock
295
296	ldr	r4, cm_idlest1_core
297wait_sdrc_ready:
298	ldr	r5, [r4]
299	tst	r5, #0x2
300	bne	wait_sdrc_ready
301	/* allow DLL powerdown upon hw idle req */
302	ldr	r4, sdrc_power
303	ldr	r5, [r4]
304	bic	r5, r5, #0x40
305	str	r5, [r4]
306
307/*
308 * PC-relative stores lead to undefined behaviour in Thumb-2: use a r7 as a
309 * base instead.
310 * Be careful not to clobber r7 when maintaing this code.
311 */
312
313is_dll_in_lock_mode:
314	/* Is dll in lock mode? */
315	ldr	r4, sdrc_dlla_ctrl
316	ldr	r5, [r4]
317	tst	r5, #0x4
318	bne	exit_nonoff_modes	@ Return if locked
319	/* wait till dll locks */
320	adr	r7, kick_counter
321wait_dll_lock_timed:
322	ldr	r4, wait_dll_lock_counter
323	add	r4, r4, #1
324	str	r4, [r7, #wait_dll_lock_counter - kick_counter]
325	ldr	r4, sdrc_dlla_status
326	/* Wait 20uS for lock */
327	mov	r6, #8
328wait_dll_lock:
329	subs	r6, r6, #0x1
330	beq	kick_dll
331	ldr	r5, [r4]
332	and	r5, r5, #0x4
333	cmp	r5, #0x4
334	bne	wait_dll_lock
335	b	exit_nonoff_modes	@ Return when locked
336
337	/* disable/reenable DLL if not locked */
338kick_dll:
339	ldr	r4, sdrc_dlla_ctrl
340	ldr	r5, [r4]
341	mov	r6, r5
342	bic	r6, #(1<<3)		@ disable dll
343	str	r6, [r4]
344	dsb
345	orr	r6, r6, #(1<<3)		@ enable dll
346	str	r6, [r4]
347	dsb
348	ldr	r4, kick_counter
349	add	r4, r4, #1
350	str	r4, [r7]		@ kick_counter
351	b	wait_dll_lock_timed
352
353exit_nonoff_modes:
354	/* Re-enable C-bit if needed */
355	mrc	p15, 0, r0, c1, c0, 0
356	tst	r0, #(1 << 2)		@ Check C bit enabled?
357	orreq	r0, r0, #(1 << 2)	@ Enable the C bit if cleared
358	mcreq	p15, 0, r0, c1, c0, 0
359	isb
360
361/*
362 * ===================================
363 * == Exit point from non-OFF modes ==
364 * ===================================
365 */
366	ldmfd	sp!, {r4 - r11, pc}	@ restore regs and return
367
368/*
369 * Local variables
370 */
371sdrc_power:
372	.word	SDRC_POWER_V
373cm_idlest1_core:
374	.word	CM_IDLEST1_CORE_V
375cm_idlest_ckgen:
376	.word	CM_IDLEST_CKGEN_V
377sdrc_dlla_status:
378	.word	SDRC_DLLA_STATUS_V
379sdrc_dlla_ctrl:
380	.word	SDRC_DLLA_CTRL_V
381	/*
382	 * When exporting to userspace while the counters are in SRAM,
383	 * these 2 words need to be at the end to facilitate retrival!
384	 */
385kick_counter:
386	.word	0
387wait_dll_lock_counter:
388	.word	0
389
390ENTRY(omap3_do_wfi_sz)
391	.word	. - omap3_do_wfi
392
393
394/*
395 * ==============================
396 * == Resume path for OFF mode ==
397 * ==============================
398 */
399
400/*
401 * The restore_* functions are called by the ROM code
402 *  when back from WFI in OFF mode.
403 * Cf. the get_*restore_pointer functions.
404 *
405 *  restore_es3: applies to 34xx >= ES3.0
406 *  restore_3630: applies to 36xx
407 *  restore: common code for 3xxx
408 *
409 * Note: when back from CORE and MPU OFF mode we are running
410 *  from SDRAM, without MMU, without the caches and prediction.
411 *  Also the SRAM content has been cleared.
412 */
413ENTRY(omap3_restore_es3)
414	ldr	r5, pm_prepwstst_core_p
415	ldr	r4, [r5]
416	and	r4, r4, #0x3
417	cmp	r4, #0x0	@ Check if previous power state of CORE is OFF
418	bne	omap3_restore	@ Fall through to OMAP3 common code
419	adr	r0, es3_sdrc_fix
420	ldr	r1, sram_base
421	ldr	r2, es3_sdrc_fix_sz
422	mov	r2, r2, ror #2
423copy_to_sram:
424	ldmia	r0!, {r3}	@ val = *src
425	stmia	r1!, {r3}	@ *dst = val
426	subs	r2, r2, #0x1	@ num_words--
427	bne	copy_to_sram
428	ldr	r1, sram_base
429	blx	r1
430	b	omap3_restore	@ Fall through to OMAP3 common code
431ENDPROC(omap3_restore_es3)
432
433ENTRY(omap3_restore_3630)
434	ldr	r1, pm_prepwstst_core_p
435	ldr	r2, [r1]
436	and	r2, r2, #0x3
437	cmp	r2, #0x0	@ Check if previous power state of CORE is OFF
438	bne	omap3_restore	@ Fall through to OMAP3 common code
439	/* Disable RTA before giving control */
440	ldr	r1, control_mem_rta
441	mov	r2, #OMAP36XX_RTA_DISABLE
442	str	r2, [r1]
443ENDPROC(omap3_restore_3630)
444
445	/* Fall through to common code for the remaining logic */
446
447ENTRY(omap3_restore)
448	/*
449	 * Read the pwstctrl register to check the reason for mpu reset.
450	 * This tells us what was lost.
451	 */
452	ldr	r1, pm_pwstctrl_mpu
453	ldr	r2, [r1]
454	and	r2, r2, #0x3
455	cmp	r2, #0x0	@ Check if target power state was OFF or RET
456	bne	logic_l1_restore
457
458	ldr	r0, l2dis_3630
459	cmp	r0, #0x1	@ should we disable L2 on 3630?
460	bne	skipl2dis
461	mrc	p15, 0, r0, c1, c0, 1
462	bic	r0, r0, #2	@ disable L2 cache
463	mcr	p15, 0, r0, c1, c0, 1
464skipl2dis:
465	ldr	r0, control_stat
466	ldr	r1, [r0]
467	and	r1, #0x700
468	cmp	r1, #0x300
469	beq	l2_inv_gp
470	mov	r0, #40			@ set service ID for PPA
471	mov	r12, r0			@ copy secure Service ID in r12
472	mov	r1, #0			@ set task id for ROM code in r1
473	mov	r2, #4			@ set some flags in r2, r6
474	mov	r6, #0xff
475	adr	r3, l2_inv_api_params	@ r3 points to dummy parameters
476	dsb				@ data write barrier
477	dmb				@ data memory barrier
478	smc	#1			@ call SMI monitor (smi #1)
479	/* Write to Aux control register to set some bits */
480	mov	r0, #42			@ set service ID for PPA
481	mov	r12, r0			@ copy secure Service ID in r12
482	mov	r1, #0			@ set task id for ROM code in r1
483	mov	r2, #4			@ set some flags in r2, r6
484	mov	r6, #0xff
485	ldr	r4, scratchpad_base
486	ldr	r3, [r4, #0xBC]		@ r3 points to parameters
487	dsb				@ data write barrier
488	dmb				@ data memory barrier
489	smc	#1			@ call SMI monitor (smi #1)
490
491#ifdef CONFIG_OMAP3_L2_AUX_SECURE_SAVE_RESTORE
492	/* Restore L2 aux control register */
493					@ set service ID for PPA
494	mov	r0, #CONFIG_OMAP3_L2_AUX_SECURE_SERVICE_SET_ID
495	mov	r12, r0			@ copy service ID in r12
496	mov	r1, #0			@ set task ID for ROM code in r1
497	mov	r2, #4			@ set some flags in r2, r6
498	mov	r6, #0xff
499	ldr	r4, scratchpad_base
500	ldr	r3, [r4, #0xBC]
501	adds	r3, r3, #8		@ r3 points to parameters
502	dsb				@ data write barrier
503	dmb				@ data memory barrier
504	smc	#1			@ call SMI monitor (smi #1)
505#endif
506	b	logic_l1_restore
507
508	.align
509l2_inv_api_params:
510	.word	0x1, 0x00
511l2_inv_gp:
512	/* Execute smi to invalidate L2 cache */
513	mov r12, #0x1			@ set up to invalidate L2
514	smc	#0			@ Call SMI monitor (smieq)
515	/* Write to Aux control register to set some bits */
516	ldr	r4, scratchpad_base
517	ldr	r3, [r4,#0xBC]
518	ldr	r0, [r3,#4]
519	mov	r12, #0x3
520	smc	#0			@ Call SMI monitor (smieq)
521	ldr	r4, scratchpad_base
522	ldr	r3, [r4,#0xBC]
523	ldr	r0, [r3,#12]
524	mov	r12, #0x2
525	smc	#0			@ Call SMI monitor (smieq)
526logic_l1_restore:
527	ldr	r1, l2dis_3630
528	cmp	r1, #0x1		@ Test if L2 re-enable needed on 3630
529	bne	skipl2reen
530	mrc	p15, 0, r1, c1, c0, 1
531	orr	r1, r1, #2		@ re-enable L2 cache
532	mcr	p15, 0, r1, c1, c0, 1
533skipl2reen:
534
535	/* Now branch to the common CPU resume function */
536	b	cpu_resume
537ENDPROC(omap3_restore)
538
539	.ltorg
540
541/*
542 * Local variables
543 */
544pm_prepwstst_core_p:
545	.word	PM_PREPWSTST_CORE_P
546pm_pwstctrl_mpu:
547	.word	PM_PWSTCTRL_MPU_P
548scratchpad_base:
549	.word	SCRATCHPAD_BASE_P
550sram_base:
551	.word	SRAM_BASE_P + 0x8000
552control_stat:
553	.word	CONTROL_STAT
554control_mem_rta:
555	.word	CONTROL_MEM_RTA_CTRL
556l2dis_3630:
557	.word	0
558
559/*
560 * Internal functions
561 */
562
563/*
564 * This function implements the erratum ID i443 WA, applies to 34xx >= ES3.0
565 * Copied to and run from SRAM in order to reconfigure the SDRC parameters.
566 */
567	.text
568	.align	3
569ENTRY(es3_sdrc_fix)
570	ldr	r4, sdrc_syscfg		@ get config addr
571	ldr	r5, [r4]		@ get value
572	tst	r5, #0x100		@ is part access blocked
573	it	eq
574	biceq	r5, r5, #0x100		@ clear bit if set
575	str	r5, [r4]		@ write back change
576	ldr	r4, sdrc_mr_0		@ get config addr
577	ldr	r5, [r4]		@ get value
578	str	r5, [r4]		@ write back change
579	ldr	r4, sdrc_emr2_0		@ get config addr
580	ldr	r5, [r4]		@ get value
581	str	r5, [r4]		@ write back change
582	ldr	r4, sdrc_manual_0	@ get config addr
583	mov	r5, #0x2		@ autorefresh command
584	str	r5, [r4]		@ kick off refreshes
585	ldr	r4, sdrc_mr_1		@ get config addr
586	ldr	r5, [r4]		@ get value
587	str	r5, [r4]		@ write back change
588	ldr	r4, sdrc_emr2_1		@ get config addr
589	ldr	r5, [r4]		@ get value
590	str	r5, [r4]		@ write back change
591	ldr	r4, sdrc_manual_1	@ get config addr
592	mov	r5, #0x2		@ autorefresh command
593	str	r5, [r4]		@ kick off refreshes
594	bx	lr
595
596/*
597 * Local variables
598 */
599	.align
600sdrc_syscfg:
601	.word	SDRC_SYSCONFIG_P
602sdrc_mr_0:
603	.word	SDRC_MR_0_P
604sdrc_emr2_0:
605	.word	SDRC_EMR2_0_P
606sdrc_manual_0:
607	.word	SDRC_MANUAL_0_P
608sdrc_mr_1:
609	.word	SDRC_MR_1_P
610sdrc_emr2_1:
611	.word	SDRC_EMR2_1_P
612sdrc_manual_1:
613	.word	SDRC_MANUAL_1_P
614ENDPROC(es3_sdrc_fix)
615ENTRY(es3_sdrc_fix_sz)
616	.word	. - es3_sdrc_fix
617