xref: /openbmc/linux/arch/arm/mach-omap2/sleep34xx.S (revision 9cfc5c90)
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	b	omap3_do_wfi
207ENDPROC(omap34xx_cpu_suspend)
208omap3_do_wfi_sram_addr:
209	.word omap3_do_wfi_sram
210kernel_flush:
211	.word v7_flush_dcache_all
212
213/* ===================================
214 * == WFI instruction => Enter idle ==
215 * ===================================
216 */
217
218/*
219 * Do WFI instruction
220 * Includes the resume path for non-OFF modes
221 *
222 * This code gets copied to internal SRAM and is accessible
223 * from both SDRAM and SRAM:
224 * - executed from SRAM for non-off modes (omap3_do_wfi_sram),
225 * - executed from SDRAM for OFF mode (omap3_do_wfi).
226 */
227	.align	3
228ENTRY(omap3_do_wfi)
229	ldr	r4, sdrc_power		@ read the SDRC_POWER register
230	ldr	r5, [r4]		@ read the contents of SDRC_POWER
231	orr	r5, r5, #0x40		@ enable self refresh on idle req
232	str	r5, [r4]		@ write back to SDRC_POWER register
233
234	/* Data memory barrier and Data sync barrier */
235	dsb
236	dmb
237
238/*
239 * ===================================
240 * == WFI instruction => Enter idle ==
241 * ===================================
242 */
243	wfi				@ wait for interrupt
244
245/*
246 * ===================================
247 * == Resume path for non-OFF modes ==
248 * ===================================
249 */
250	nop
251	nop
252	nop
253	nop
254	nop
255	nop
256	nop
257	nop
258	nop
259	nop
260
261/*
262 * This function implements the erratum ID i581 WA:
263 *  SDRC state restore before accessing the SDRAM
264 *
265 * Only used at return from non-OFF mode. For OFF
266 * mode the ROM code configures the SDRC and
267 * the DPLL before calling the restore code directly
268 * from DDR.
269 */
270
271/* Make sure SDRC accesses are ok */
272wait_sdrc_ok:
273
274/* DPLL3 must be locked before accessing the SDRC. Maybe the HW ensures this */
275	ldr	r4, cm_idlest_ckgen
276wait_dpll3_lock:
277	ldr	r5, [r4]
278	tst	r5, #1
279	beq	wait_dpll3_lock
280
281	ldr	r4, cm_idlest1_core
282wait_sdrc_ready:
283	ldr	r5, [r4]
284	tst	r5, #0x2
285	bne	wait_sdrc_ready
286	/* allow DLL powerdown upon hw idle req */
287	ldr	r4, sdrc_power
288	ldr	r5, [r4]
289	bic	r5, r5, #0x40
290	str	r5, [r4]
291
292/*
293 * PC-relative stores lead to undefined behaviour in Thumb-2: use a r7 as a
294 * base instead.
295 * Be careful not to clobber r7 when maintaing this code.
296 */
297
298is_dll_in_lock_mode:
299	/* Is dll in lock mode? */
300	ldr	r4, sdrc_dlla_ctrl
301	ldr	r5, [r4]
302	tst	r5, #0x4
303	bne	exit_nonoff_modes	@ Return if locked
304	/* wait till dll locks */
305	adr	r7, kick_counter
306wait_dll_lock_timed:
307	ldr	r4, wait_dll_lock_counter
308	add	r4, r4, #1
309	str	r4, [r7, #wait_dll_lock_counter - kick_counter]
310	ldr	r4, sdrc_dlla_status
311	/* Wait 20uS for lock */
312	mov	r6, #8
313wait_dll_lock:
314	subs	r6, r6, #0x1
315	beq	kick_dll
316	ldr	r5, [r4]
317	and	r5, r5, #0x4
318	cmp	r5, #0x4
319	bne	wait_dll_lock
320	b	exit_nonoff_modes	@ Return when locked
321
322	/* disable/reenable DLL if not locked */
323kick_dll:
324	ldr	r4, sdrc_dlla_ctrl
325	ldr	r5, [r4]
326	mov	r6, r5
327	bic	r6, #(1<<3)		@ disable dll
328	str	r6, [r4]
329	dsb
330	orr	r6, r6, #(1<<3)		@ enable dll
331	str	r6, [r4]
332	dsb
333	ldr	r4, kick_counter
334	add	r4, r4, #1
335	str	r4, [r7]		@ kick_counter
336	b	wait_dll_lock_timed
337
338exit_nonoff_modes:
339	/* Re-enable C-bit if needed */
340	mrc	p15, 0, r0, c1, c0, 0
341	tst	r0, #(1 << 2)		@ Check C bit enabled?
342	orreq	r0, r0, #(1 << 2)	@ Enable the C bit if cleared
343	mcreq	p15, 0, r0, c1, c0, 0
344	isb
345
346/*
347 * ===================================
348 * == Exit point from non-OFF modes ==
349 * ===================================
350 */
351	ldmfd	sp!, {r4 - r11, pc}	@ restore regs and return
352ENDPROC(omap3_do_wfi)
353sdrc_power:
354	.word	SDRC_POWER_V
355cm_idlest1_core:
356	.word	CM_IDLEST1_CORE_V
357cm_idlest_ckgen:
358	.word	CM_IDLEST_CKGEN_V
359sdrc_dlla_status:
360	.word	SDRC_DLLA_STATUS_V
361sdrc_dlla_ctrl:
362	.word	SDRC_DLLA_CTRL_V
363	/*
364	 * When exporting to userspace while the counters are in SRAM,
365	 * these 2 words need to be at the end to facilitate retrival!
366	 */
367kick_counter:
368	.word	0
369wait_dll_lock_counter:
370	.word	0
371
372ENTRY(omap3_do_wfi_sz)
373	.word	. - omap3_do_wfi
374
375
376/*
377 * ==============================
378 * == Resume path for OFF mode ==
379 * ==============================
380 */
381
382/*
383 * The restore_* functions are called by the ROM code
384 *  when back from WFI in OFF mode.
385 * Cf. the get_*restore_pointer functions.
386 *
387 *  restore_es3: applies to 34xx >= ES3.0
388 *  restore_3630: applies to 36xx
389 *  restore: common code for 3xxx
390 *
391 * Note: when back from CORE and MPU OFF mode we are running
392 *  from SDRAM, without MMU, without the caches and prediction.
393 *  Also the SRAM content has been cleared.
394 */
395ENTRY(omap3_restore_es3)
396	ldr	r5, pm_prepwstst_core_p
397	ldr	r4, [r5]
398	and	r4, r4, #0x3
399	cmp	r4, #0x0	@ Check if previous power state of CORE is OFF
400	bne	omap3_restore	@ Fall through to OMAP3 common code
401	adr	r0, es3_sdrc_fix
402	ldr	r1, sram_base
403	ldr	r2, es3_sdrc_fix_sz
404	mov	r2, r2, ror #2
405copy_to_sram:
406	ldmia	r0!, {r3}	@ val = *src
407	stmia	r1!, {r3}	@ *dst = val
408	subs	r2, r2, #0x1	@ num_words--
409	bne	copy_to_sram
410	ldr	r1, sram_base
411	blx	r1
412	b	omap3_restore	@ Fall through to OMAP3 common code
413ENDPROC(omap3_restore_es3)
414
415ENTRY(omap3_restore_3630)
416	ldr	r1, pm_prepwstst_core_p
417	ldr	r2, [r1]
418	and	r2, r2, #0x3
419	cmp	r2, #0x0	@ Check if previous power state of CORE is OFF
420	bne	omap3_restore	@ Fall through to OMAP3 common code
421	/* Disable RTA before giving control */
422	ldr	r1, control_mem_rta
423	mov	r2, #OMAP36XX_RTA_DISABLE
424	str	r2, [r1]
425ENDPROC(omap3_restore_3630)
426
427	/* Fall through to common code for the remaining logic */
428
429ENTRY(omap3_restore)
430	/*
431	 * Read the pwstctrl register to check the reason for mpu reset.
432	 * This tells us what was lost.
433	 */
434	ldr	r1, pm_pwstctrl_mpu
435	ldr	r2, [r1]
436	and	r2, r2, #0x3
437	cmp	r2, #0x0	@ Check if target power state was OFF or RET
438	bne	logic_l1_restore
439
440	ldr	r0, l2dis_3630
441	cmp	r0, #0x1	@ should we disable L2 on 3630?
442	bne	skipl2dis
443	mrc	p15, 0, r0, c1, c0, 1
444	bic	r0, r0, #2	@ disable L2 cache
445	mcr	p15, 0, r0, c1, c0, 1
446skipl2dis:
447	ldr	r0, control_stat
448	ldr	r1, [r0]
449	and	r1, #0x700
450	cmp	r1, #0x300
451	beq	l2_inv_gp
452	mov	r0, #40			@ set service ID for PPA
453	mov	r12, r0			@ copy secure Service ID in r12
454	mov	r1, #0			@ set task id for ROM code in r1
455	mov	r2, #4			@ set some flags in r2, r6
456	mov	r6, #0xff
457	adr	r3, l2_inv_api_params	@ r3 points to dummy parameters
458	dsb				@ data write barrier
459	dmb				@ data memory barrier
460	smc	#1			@ call SMI monitor (smi #1)
461	/* Write to Aux control register to set some bits */
462	mov	r0, #42			@ set service ID for PPA
463	mov	r12, r0			@ copy secure Service ID in r12
464	mov	r1, #0			@ set task id for ROM code in r1
465	mov	r2, #4			@ set some flags in r2, r6
466	mov	r6, #0xff
467	ldr	r4, scratchpad_base
468	ldr	r3, [r4, #0xBC]		@ r3 points to parameters
469	dsb				@ data write barrier
470	dmb				@ data memory barrier
471	smc	#1			@ call SMI monitor (smi #1)
472
473#ifdef CONFIG_OMAP3_L2_AUX_SECURE_SAVE_RESTORE
474	/* Restore L2 aux control register */
475					@ set service ID for PPA
476	mov	r0, #CONFIG_OMAP3_L2_AUX_SECURE_SERVICE_SET_ID
477	mov	r12, r0			@ copy service ID in r12
478	mov	r1, #0			@ set task ID for ROM code in r1
479	mov	r2, #4			@ set some flags in r2, r6
480	mov	r6, #0xff
481	ldr	r4, scratchpad_base
482	ldr	r3, [r4, #0xBC]
483	adds	r3, r3, #8		@ r3 points to parameters
484	dsb				@ data write barrier
485	dmb				@ data memory barrier
486	smc	#1			@ call SMI monitor (smi #1)
487#endif
488	b	logic_l1_restore
489
490	.align
491l2_inv_api_params:
492	.word	0x1, 0x00
493l2_inv_gp:
494	/* Execute smi to invalidate L2 cache */
495	mov r12, #0x1			@ set up to invalidate L2
496	smc	#0			@ Call SMI monitor (smieq)
497	/* Write to Aux control register to set some bits */
498	ldr	r4, scratchpad_base
499	ldr	r3, [r4,#0xBC]
500	ldr	r0, [r3,#4]
501	mov	r12, #0x3
502	smc	#0			@ Call SMI monitor (smieq)
503	ldr	r4, scratchpad_base
504	ldr	r3, [r4,#0xBC]
505	ldr	r0, [r3,#12]
506	mov	r12, #0x2
507	smc	#0			@ Call SMI monitor (smieq)
508logic_l1_restore:
509	ldr	r1, l2dis_3630
510	cmp	r1, #0x1		@ Test if L2 re-enable needed on 3630
511	bne	skipl2reen
512	mrc	p15, 0, r1, c1, c0, 1
513	orr	r1, r1, #2		@ re-enable L2 cache
514	mcr	p15, 0, r1, c1, c0, 1
515skipl2reen:
516
517	/* Now branch to the common CPU resume function */
518	b	cpu_resume
519ENDPROC(omap3_restore)
520
521	.ltorg
522
523/*
524 * Local variables
525 */
526pm_prepwstst_core_p:
527	.word	PM_PREPWSTST_CORE_P
528pm_pwstctrl_mpu:
529	.word	PM_PWSTCTRL_MPU_P
530scratchpad_base:
531	.word	SCRATCHPAD_BASE_P
532sram_base:
533	.word	SRAM_BASE_P + 0x8000
534control_stat:
535	.word	CONTROL_STAT
536control_mem_rta:
537	.word	CONTROL_MEM_RTA_CTRL
538l2dis_3630:
539	.word	0
540
541/*
542 * Internal functions
543 */
544
545/*
546 * This function implements the erratum ID i443 WA, applies to 34xx >= ES3.0
547 * Copied to and run from SRAM in order to reconfigure the SDRC parameters.
548 */
549	.text
550	.align	3
551ENTRY(es3_sdrc_fix)
552	ldr	r4, sdrc_syscfg		@ get config addr
553	ldr	r5, [r4]		@ get value
554	tst	r5, #0x100		@ is part access blocked
555	it	eq
556	biceq	r5, r5, #0x100		@ clear bit if set
557	str	r5, [r4]		@ write back change
558	ldr	r4, sdrc_mr_0		@ get config addr
559	ldr	r5, [r4]		@ get value
560	str	r5, [r4]		@ write back change
561	ldr	r4, sdrc_emr2_0		@ get config addr
562	ldr	r5, [r4]		@ get value
563	str	r5, [r4]		@ write back change
564	ldr	r4, sdrc_manual_0	@ get config addr
565	mov	r5, #0x2		@ autorefresh command
566	str	r5, [r4]		@ kick off refreshes
567	ldr	r4, sdrc_mr_1		@ get config addr
568	ldr	r5, [r4]		@ get value
569	str	r5, [r4]		@ write back change
570	ldr	r4, sdrc_emr2_1		@ get config addr
571	ldr	r5, [r4]		@ get value
572	str	r5, [r4]		@ write back change
573	ldr	r4, sdrc_manual_1	@ get config addr
574	mov	r5, #0x2		@ autorefresh command
575	str	r5, [r4]		@ kick off refreshes
576	bx	lr
577
578/*
579 * Local variables
580 */
581	.align
582sdrc_syscfg:
583	.word	SDRC_SYSCONFIG_P
584sdrc_mr_0:
585	.word	SDRC_MR_0_P
586sdrc_emr2_0:
587	.word	SDRC_EMR2_0_P
588sdrc_manual_0:
589	.word	SDRC_MANUAL_0_P
590sdrc_mr_1:
591	.word	SDRC_MR_1_P
592sdrc_emr2_1:
593	.word	SDRC_EMR2_1_P
594sdrc_manual_1:
595	.word	SDRC_MANUAL_1_P
596ENDPROC(es3_sdrc_fix)
597ENTRY(es3_sdrc_fix_sz)
598	.word	. - es3_sdrc_fix
599