xref: /openbmc/linux/arch/arm/mach-omap2/sleep34xx.S (revision a72b9869) 
1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * (C) Copyright 2007
4 * Texas Instruments
5 * Karthik Dasu <karthik-dp@ti.com>
6 *
7 * (C) Copyright 2004
8 * Texas Instruments, <www.ti.com>
9 * Richard Woodruff <r-woodruff2@ti.com>
10 */
11#include <linux/linkage.h>
12
13#include <asm/assembler.h>
14
15#include "omap34xx.h"
16#include "iomap.h"
17#include "cm3xxx.h"
18#include "prm3xxx.h"
19#include "sdrc.h"
20#include "sram.h"
21#include "control.h"
22
23/*
24 * Registers access definitions
25 */
26#define SDRC_SCRATCHPAD_SEM_OFFS	0xc
27#define SDRC_SCRATCHPAD_SEM_V	OMAP343X_SCRATCHPAD_REGADDR\
28					(SDRC_SCRATCHPAD_SEM_OFFS)
29#define PM_PREPWSTST_CORE_P	OMAP3430_PRM_BASE + CORE_MOD +\
30					OMAP3430_PM_PREPWSTST
31#define PM_PWSTCTRL_MPU_P	OMAP3430_PRM_BASE + MPU_MOD + OMAP2_PM_PWSTCTRL
32#define CM_IDLEST1_CORE_V	OMAP34XX_CM_REGADDR(CORE_MOD, CM_IDLEST1)
33#define CM_IDLEST_CKGEN_V	OMAP34XX_CM_REGADDR(PLL_MOD, CM_IDLEST)
34#define SRAM_BASE_P		OMAP3_SRAM_PA
35#define CONTROL_STAT		OMAP343X_CTRL_BASE + OMAP343X_CONTROL_STATUS
36#define CONTROL_MEM_RTA_CTRL	(OMAP343X_CTRL_BASE +\
37					OMAP36XX_CONTROL_MEM_RTA_CTRL)
38
39/* Move this as correct place is available */
40#define SCRATCHPAD_MEM_OFFS	0x310
41#define SCRATCHPAD_BASE_P	(OMAP343X_CTRL_BASE +\
42					OMAP343X_CONTROL_MEM_WKUP +\
43					SCRATCHPAD_MEM_OFFS)
44#define SDRC_POWER_V		OMAP34XX_SDRC_REGADDR(SDRC_POWER)
45#define SDRC_SYSCONFIG_P	(OMAP343X_SDRC_BASE + SDRC_SYSCONFIG)
46#define SDRC_MR_0_P		(OMAP343X_SDRC_BASE + SDRC_MR_0)
47#define SDRC_EMR2_0_P		(OMAP343X_SDRC_BASE + SDRC_EMR2_0)
48#define SDRC_MANUAL_0_P		(OMAP343X_SDRC_BASE + SDRC_MANUAL_0)
49#define SDRC_MR_1_P		(OMAP343X_SDRC_BASE + SDRC_MR_1)
50#define SDRC_EMR2_1_P		(OMAP343X_SDRC_BASE + SDRC_EMR2_1)
51#define SDRC_MANUAL_1_P		(OMAP343X_SDRC_BASE + SDRC_MANUAL_1)
52#define SDRC_DLLA_STATUS_V	OMAP34XX_SDRC_REGADDR(SDRC_DLLA_STATUS)
53#define SDRC_DLLA_CTRL_V	OMAP34XX_SDRC_REGADDR(SDRC_DLLA_CTRL)
54
55/*
56 * This file needs be built unconditionally as ARM to interoperate correctly
57 * with non-Thumb-2-capable firmware.
58 */
59	.arm
60
61/*
62 * API functions
63 */
64
65	.text
66/*
67 * L2 cache needs to be toggled for stable OFF mode functionality on 3630.
68 * This function sets up a flag that will allow for this toggling to take
69 * place on 3630. Hopefully some version in the future may not need this.
70 */
71ENTRY(enable_omap3630_toggle_l2_on_restore)
72	stmfd	sp!, {lr}	@ save registers on stack
73	/* Setup so that we will disable and enable l2 */
74	mov	r1, #0x1
75	adr	r3, l2dis_3630_offset
76	ldr	r2, [r3]		@ value for offset
77	str	r1, [r2, r3]		@ write to l2dis_3630
78	ldmfd	sp!, {pc}	@ restore regs and return
79ENDPROC(enable_omap3630_toggle_l2_on_restore)
80
81/*
82 * Function to call rom code to save secure ram context.
83 *
84 * r0 = physical address of the parameters
85 */
86	.arch armv7-a
87	.arch_extension sec
88ENTRY(save_secure_ram_context)
89	stmfd	sp!, {r4 - r11, lr}	@ save registers on stack
90	mov	r3, r0			@ physical address of parameters
91	mov	r0, #25			@ set service ID for PPA
92	mov	r12, r0			@ copy secure service ID in r12
93	mov	r1, #0			@ set task id for ROM code in r1
94	mov	r2, #4			@ set some flags in r2, r6
95	mov	r6, #0xff
96	dsb				@ data write barrier
97	dmb				@ data memory barrier
98	smc	#1			@ call SMI monitor (smi #1)
99	nop
100	nop
101	nop
102	nop
103	ldmfd	sp!, {r4 - r11, pc}
104ENDPROC(save_secure_ram_context)
105
106/*
107 * ======================
108 * == Idle entry point ==
109 * ======================
110 */
111
112/*
113 * Forces OMAP into idle state
114 *
115 * omap34xx_cpu_suspend() - This bit of code saves the CPU context if needed
116 * and executes the WFI instruction. Calling WFI effectively changes the
117 * power domains states to the desired target power states.
118 *
119 *
120 * Notes:
121 * - only the minimum set of functions gets copied to internal SRAM at boot
122 *   and after wake-up from OFF mode, cf. omap_push_sram_idle. The function
123 *   pointers in SDRAM or SRAM are called depending on the desired low power
124 *   target state.
125 * - when the OMAP wakes up it continues at different execution points
126 *   depending on the low power mode (non-OFF vs OFF modes),
127 *   cf. 'Resume path for xxx mode' comments.
128 */
129	.align	3
130ENTRY(omap34xx_cpu_suspend)
131	stmfd	sp!, {r4 - r11, lr}	@ save registers on stack
132
133	/*
134	 * r0 contains information about saving context:
135	 *   0 - No context lost
136	 *   1 - Only L1 and logic lost
137	 *   2 - Only L2 lost (Even L1 is retained we clean it along with L2)
138	 *   3 - Both L1 and L2 lost and logic lost
139	 */
140
141	/*
142	 * For OFF mode: save context and jump to WFI in SDRAM (omap3_do_wfi)
143	 * For non-OFF modes: jump to the WFI code in SRAM (omap3_do_wfi_sram)
144	 */
145	ldr	r4, omap3_do_wfi_sram_addr
146	ldr	r5, [r4]
147	cmp	r0, #0x0		@ If no context save required,
148	bxeq	r5			@  jump to the WFI code in SRAM
149
150
151	/* Otherwise fall through to the save context code */
152save_context_wfi:
153	/*
154	 * jump out to kernel flush routine
155	 *  - reuse that code is better
156	 *  - it executes in a cached space so is faster than refetch per-block
157	 *  - should be faster and will change with kernel
158	 *  - 'might' have to copy address, load and jump to it
159	 * Flush all data from the L1 data cache before disabling
160	 * SCTLR.C bit.
161	 */
162	ldr	r1, kernel_flush
163	mov	lr, pc
164	bx	r1
165
166	/*
167	 * Clear the SCTLR.C bit to prevent further data cache
168	 * allocation. Clearing SCTLR.C would make all the data accesses
169	 * strongly ordered and would not hit the cache.
170	 */
171	mrc	p15, 0, r0, c1, c0, 0
172	bic	r0, r0, #(1 << 2)	@ Disable the C bit
173	mcr	p15, 0, r0, c1, c0, 0
174	isb
175
176	/*
177	 * Invalidate L1 data cache. Even though only invalidate is
178	 * necessary exported flush API is used here. Doing clean
179	 * on already clean cache would be almost NOP.
180	 */
181	ldr	r1, kernel_flush
182	blx	r1
183	b	omap3_do_wfi
184ENDPROC(omap34xx_cpu_suspend)
185omap3_do_wfi_sram_addr:
186	.word omap3_do_wfi_sram
187kernel_flush:
188	.word v7_flush_dcache_all
189
190/* ===================================
191 * == WFI instruction => Enter idle ==
192 * ===================================
193 */
194
195/*
196 * Do WFI instruction
197 * Includes the resume path for non-OFF modes
198 *
199 * This code gets copied to internal SRAM and is accessible
200 * from both SDRAM and SRAM:
201 * - executed from SRAM for non-off modes (omap3_do_wfi_sram),
202 * - executed from SDRAM for OFF mode (omap3_do_wfi).
203 */
204	.align	3
205ENTRY(omap3_do_wfi)
206	ldr	r4, sdrc_power		@ read the SDRC_POWER register
207	ldr	r5, [r4]		@ read the contents of SDRC_POWER
208	orr	r5, r5, #0x40		@ enable self refresh on idle req
209	str	r5, [r4]		@ write back to SDRC_POWER register
210
211	/* Data memory barrier and Data sync barrier */
212	dsb
213	dmb
214
215/*
216 * ===================================
217 * == WFI instruction => Enter idle ==
218 * ===================================
219 */
220	wfi				@ wait for interrupt
221
222/*
223 * ===================================
224 * == Resume path for non-OFF modes ==
225 * ===================================
226 */
227	nop
228	nop
229	nop
230	nop
231	nop
232	nop
233	nop
234	nop
235	nop
236	nop
237
238/*
239 * This function implements the erratum ID i581 WA:
240 *  SDRC state restore before accessing the SDRAM
241 *
242 * Only used at return from non-OFF mode. For OFF
243 * mode the ROM code configures the SDRC and
244 * the DPLL before calling the restore code directly
245 * from DDR.
246 */
247
248/* Make sure SDRC accesses are ok */
249wait_sdrc_ok:
250
251/* DPLL3 must be locked before accessing the SDRC. Maybe the HW ensures this */
252	ldr	r4, cm_idlest_ckgen
253wait_dpll3_lock:
254	ldr	r5, [r4]
255	tst	r5, #1
256	beq	wait_dpll3_lock
257
258	ldr	r4, cm_idlest1_core
259wait_sdrc_ready:
260	ldr	r5, [r4]
261	tst	r5, #0x2
262	bne	wait_sdrc_ready
263	/* allow DLL powerdown upon hw idle req */
264	ldr	r4, sdrc_power
265	ldr	r5, [r4]
266	bic	r5, r5, #0x40
267	str	r5, [r4]
268
269is_dll_in_lock_mode:
270	/* Is dll in lock mode? */
271	ldr	r4, sdrc_dlla_ctrl
272	ldr	r5, [r4]
273	tst	r5, #0x4
274	bne	exit_nonoff_modes	@ Return if locked
275	/* wait till dll locks */
276wait_dll_lock_timed:
277	ldr	r4, sdrc_dlla_status
278	/* Wait 20uS for lock */
279	mov	r6, #8
280wait_dll_lock:
281	subs	r6, r6, #0x1
282	beq	kick_dll
283	ldr	r5, [r4]
284	and	r5, r5, #0x4
285	cmp	r5, #0x4
286	bne	wait_dll_lock
287	b	exit_nonoff_modes	@ Return when locked
288
289	/* disable/reenable DLL if not locked */
290kick_dll:
291	ldr	r4, sdrc_dlla_ctrl
292	ldr	r5, [r4]
293	mov	r6, r5
294	bic	r6, #(1<<3)		@ disable dll
295	str	r6, [r4]
296	dsb
297	orr	r6, r6, #(1<<3)		@ enable dll
298	str	r6, [r4]
299	dsb
300	b	wait_dll_lock_timed
301
302exit_nonoff_modes:
303	/* Re-enable C-bit if needed */
304	mrc	p15, 0, r0, c1, c0, 0
305	tst	r0, #(1 << 2)		@ Check C bit enabled?
306	orreq	r0, r0, #(1 << 2)	@ Enable the C bit if cleared
307	mcreq	p15, 0, r0, c1, c0, 0
308	isb
309
310/*
311 * ===================================
312 * == Exit point from non-OFF modes ==
313 * ===================================
314 */
315	ldmfd	sp!, {r4 - r11, pc}	@ restore regs and return
316ENDPROC(omap3_do_wfi)
317sdrc_power:
318	.word	SDRC_POWER_V
319cm_idlest1_core:
320	.word	CM_IDLEST1_CORE_V
321cm_idlest_ckgen:
322	.word	CM_IDLEST_CKGEN_V
323sdrc_dlla_status:
324	.word	SDRC_DLLA_STATUS_V
325sdrc_dlla_ctrl:
326	.word	SDRC_DLLA_CTRL_V
327ENTRY(omap3_do_wfi_sz)
328	.word	. - omap3_do_wfi
329
330
331/*
332 * ==============================
333 * == Resume path for OFF mode ==
334 * ==============================
335 */
336
337/*
338 * The restore_* functions are called by the ROM code
339 *  when back from WFI in OFF mode.
340 * Cf. the get_*restore_pointer functions.
341 *
342 *  restore_es3: applies to 34xx >= ES3.0
343 *  restore_3630: applies to 36xx
344 *  restore: common code for 3xxx
345 *
346 * Note: when back from CORE and MPU OFF mode we are running
347 *  from SDRAM, without MMU, without the caches and prediction.
348 *  Also the SRAM content has been cleared.
349 */
350ENTRY(omap3_restore_es3)
351	ldr	r5, pm_prepwstst_core_p
352	ldr	r4, [r5]
353	and	r4, r4, #0x3
354	cmp	r4, #0x0	@ Check if previous power state of CORE is OFF
355	bne	omap3_restore	@ Fall through to OMAP3 common code
356	adr	r0, es3_sdrc_fix
357	ldr	r1, sram_base
358	ldr	r2, es3_sdrc_fix_sz
359	mov	r2, r2, ror #2
360copy_to_sram:
361	ldmia	r0!, {r3}	@ val = *src
362	stmia	r1!, {r3}	@ *dst = val
363	subs	r2, r2, #0x1	@ num_words--
364	bne	copy_to_sram
365	ldr	r1, sram_base
366	blx	r1
367	b	omap3_restore	@ Fall through to OMAP3 common code
368ENDPROC(omap3_restore_es3)
369
370ENTRY(omap3_restore_3630)
371	ldr	r1, pm_prepwstst_core_p
372	ldr	r2, [r1]
373	and	r2, r2, #0x3
374	cmp	r2, #0x0	@ Check if previous power state of CORE is OFF
375	bne	omap3_restore	@ Fall through to OMAP3 common code
376	/* Disable RTA before giving control */
377	ldr	r1, control_mem_rta
378	mov	r2, #OMAP36XX_RTA_DISABLE
379	str	r2, [r1]
380ENDPROC(omap3_restore_3630)
381
382	/* Fall through to common code for the remaining logic */
383
384ENTRY(omap3_restore)
385	/*
386	 * Read the pwstctrl register to check the reason for mpu reset.
387	 * This tells us what was lost.
388	 */
389	ldr	r1, pm_pwstctrl_mpu
390	ldr	r2, [r1]
391	and	r2, r2, #0x3
392	cmp	r2, #0x0	@ Check if target power state was OFF or RET
393	bne	logic_l1_restore
394
395	adr	r1, l2dis_3630_offset	@ address for offset
396	ldr	r0, [r1]		@ value for offset
397	ldr	r0, [r1, r0]		@ value at l2dis_3630
398	cmp	r0, #0x1	@ should we disable L2 on 3630?
399	bne	skipl2dis
400	mrc	p15, 0, r0, c1, c0, 1
401	bic	r0, r0, #2	@ disable L2 cache
402	mcr	p15, 0, r0, c1, c0, 1
403skipl2dis:
404	ldr	r0, control_stat
405	ldr	r1, [r0]
406	and	r1, #0x700
407	cmp	r1, #0x300
408	beq	l2_inv_gp
409	adr	r0, l2_inv_api_params_offset
410	ldr	r3, [r0]
411	add	r3, r3, r0		@ r3 points to dummy parameters
412	mov	r0, #40			@ set service ID for PPA
413	mov	r12, r0			@ copy secure Service ID in r12
414	mov	r1, #0			@ set task id for ROM code in r1
415	mov	r2, #4			@ set some flags in r2, r6
416	mov	r6, #0xff
417	dsb				@ data write barrier
418	dmb				@ data memory barrier
419	smc	#1			@ call SMI monitor (smi #1)
420	/* Write to Aux control register to set some bits */
421	mov	r0, #42			@ set service ID for PPA
422	mov	r12, r0			@ copy secure Service ID in r12
423	mov	r1, #0			@ set task id for ROM code in r1
424	mov	r2, #4			@ set some flags in r2, r6
425	mov	r6, #0xff
426	ldr	r4, scratchpad_base
427	ldr	r3, [r4, #0xBC]		@ r3 points to parameters
428	dsb				@ data write barrier
429	dmb				@ data memory barrier
430	smc	#1			@ call SMI monitor (smi #1)
431
432#ifdef CONFIG_OMAP3_L2_AUX_SECURE_SAVE_RESTORE
433	/* Restore L2 aux control register */
434					@ set service ID for PPA
435	mov	r0, #CONFIG_OMAP3_L2_AUX_SECURE_SERVICE_SET_ID
436	mov	r12, r0			@ copy service ID in r12
437	mov	r1, #0			@ set task ID for ROM code in r1
438	mov	r2, #4			@ set some flags in r2, r6
439	mov	r6, #0xff
440	ldr	r4, scratchpad_base
441	ldr	r3, [r4, #0xBC]
442	adds	r3, r3, #8		@ r3 points to parameters
443	dsb				@ data write barrier
444	dmb				@ data memory barrier
445	smc	#1			@ call SMI monitor (smi #1)
446#endif
447	b	logic_l1_restore
448
449	.align
450l2_inv_api_params_offset:
451	.long	l2_inv_api_params - .
452l2_inv_gp:
453	/* Execute smi to invalidate L2 cache */
454	mov r12, #0x1			@ set up to invalidate L2
455	smc	#0			@ Call SMI monitor (smieq)
456	/* Write to Aux control register to set some bits */
457	ldr	r4, scratchpad_base
458	ldr	r3, [r4,#0xBC]
459	ldr	r0, [r3,#4]
460	mov	r12, #0x3
461	smc	#0			@ Call SMI monitor (smieq)
462	ldr	r4, scratchpad_base
463	ldr	r3, [r4,#0xBC]
464	ldr	r0, [r3,#12]
465	mov	r12, #0x2
466	smc	#0			@ Call SMI monitor (smieq)
467logic_l1_restore:
468	adr	r0, l2dis_3630_offset	@ address for offset
469	ldr	r1, [r0]		@ value for offset
470	ldr	r1, [r0, r1]		@ value at l2dis_3630
471	cmp	r1, #0x1		@ Test if L2 re-enable needed on 3630
472	bne	skipl2reen
473	mrc	p15, 0, r1, c1, c0, 1
474	orr	r1, r1, #2		@ re-enable L2 cache
475	mcr	p15, 0, r1, c1, c0, 1
476skipl2reen:
477
478	/* Now branch to the common CPU resume function */
479	b	cpu_resume
480ENDPROC(omap3_restore)
481
482	.ltorg
483
484/*
485 * Local variables
486 */
487pm_prepwstst_core_p:
488	.word	PM_PREPWSTST_CORE_P
489pm_pwstctrl_mpu:
490	.word	PM_PWSTCTRL_MPU_P
491scratchpad_base:
492	.word	SCRATCHPAD_BASE_P
493sram_base:
494	.word	SRAM_BASE_P + 0x8000
495control_stat:
496	.word	CONTROL_STAT
497control_mem_rta:
498	.word	CONTROL_MEM_RTA_CTRL
499l2dis_3630_offset:
500	.long	l2dis_3630 - .
501
502	.data
503	.align	2
504l2dis_3630:
505	.word	0
506
507	.data
508	.align	2
509l2_inv_api_params:
510	.word	0x1, 0x00
511
512/*
513 * Internal functions
514 */
515
516/*
517 * This function implements the erratum ID i443 WA, applies to 34xx >= ES3.0
518 * Copied to and run from SRAM in order to reconfigure the SDRC parameters.
519 */
520	.text
521	.align	3
522ENTRY(es3_sdrc_fix)
523	ldr	r4, sdrc_syscfg		@ get config addr
524	ldr	r5, [r4]		@ get value
525	tst	r5, #0x100		@ is part access blocked
526	it	eq
527	biceq	r5, r5, #0x100		@ clear bit if set
528	str	r5, [r4]		@ write back change
529	ldr	r4, sdrc_mr_0		@ get config addr
530	ldr	r5, [r4]		@ get value
531	str	r5, [r4]		@ write back change
532	ldr	r4, sdrc_emr2_0		@ get config addr
533	ldr	r5, [r4]		@ get value
534	str	r5, [r4]		@ write back change
535	ldr	r4, sdrc_manual_0	@ get config addr
536	mov	r5, #0x2		@ autorefresh command
537	str	r5, [r4]		@ kick off refreshes
538	ldr	r4, sdrc_mr_1		@ get config addr
539	ldr	r5, [r4]		@ get value
540	str	r5, [r4]		@ write back change
541	ldr	r4, sdrc_emr2_1		@ get config addr
542	ldr	r5, [r4]		@ get value
543	str	r5, [r4]		@ write back change
544	ldr	r4, sdrc_manual_1	@ get config addr
545	mov	r5, #0x2		@ autorefresh command
546	str	r5, [r4]		@ kick off refreshes
547	bx	lr
548
549/*
550 * Local variables
551 */
552	.align
553sdrc_syscfg:
554	.word	SDRC_SYSCONFIG_P
555sdrc_mr_0:
556	.word	SDRC_MR_0_P
557sdrc_emr2_0:
558	.word	SDRC_EMR2_0_P
559sdrc_manual_0:
560	.word	SDRC_MANUAL_0_P
561sdrc_mr_1:
562	.word	SDRC_MR_1_P
563sdrc_emr2_1:
564	.word	SDRC_EMR2_1_P
565sdrc_manual_1:
566	.word	SDRC_MANUAL_1_P
567ENDPROC(es3_sdrc_fix)
568ENTRY(es3_sdrc_fix_sz)
569	.word	. - es3_sdrc_fix
570