xref: /linux/drivers/memory/ti-emif-sram-pm.S (revision cdd5b5a9761fd66d17586e4f4ba6588c70e640ea)
1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Low level PM code for TI EMIF
4 *
5 * Copyright (C) 2016-2017 Texas Instruments Incorporated - http://www.ti.com/
6 *	Dave Gerlach
7 */
8
9#include <linux/linkage.h>
10#include <asm/assembler.h>
11#include <asm/page.h>
12
13#include "emif.h"
14#include "ti-emif-asm-offsets.h"
15
16#define EMIF_POWER_MGMT_WAIT_SELF_REFRESH_8192_CYCLES	0x00a0
17#define EMIF_POWER_MGMT_SR_TIMER_MASK			0x00f0
18#define EMIF_POWER_MGMT_SELF_REFRESH_MODE		0x0200
19#define EMIF_POWER_MGMT_SELF_REFRESH_MODE_MASK		0x0700
20
21#define EMIF_SDCFG_TYPE_DDR2				0x2 << SDRAM_TYPE_SHIFT
22#define EMIF_SDCFG_TYPE_DDR3				0x3 << SDRAM_TYPE_SHIFT
23#define EMIF_STATUS_READY				0x4
24
25#define AM43XX_EMIF_PHY_CTRL_REG_COUNT                  0x120
26
27#define EMIF_AM437X_REGISTERS				0x1
28
29	.arm
30	.align 3
31	.arch armv7-a
32
33ENTRY(ti_emif_sram)
34
35/*
36 * void ti_emif_save_context(void)
37 *
38 * Used during suspend to save the context of all required EMIF registers
39 * to local memory if the EMIF is going to lose context during the sleep
40 * transition. Operates on the VIRTUAL address of the EMIF.
41 */
42ENTRY(ti_emif_save_context)
43	stmfd   sp!, {r4 - r11, lr}     @ save registers on stack
44
45	adr	r4, ti_emif_pm_sram_data
46	ldr	r0, [r4, #EMIF_PM_BASE_ADDR_VIRT_OFFSET]
47	ldr	r2, [r4, #EMIF_PM_REGS_VIRT_OFFSET]
48
49	/* Save EMIF configuration */
50	ldr	r1, [r0, #EMIF_SDRAM_CONFIG]
51	str	r1, [r2, #EMIF_SDCFG_VAL_OFFSET]
52
53	ldr	r1, [r0, #EMIF_SDRAM_REFRESH_CONTROL]
54	str	r1, [r2, #EMIF_REF_CTRL_VAL_OFFSET]
55
56	ldr	r1, [r0, #EMIF_SDRAM_TIMING_1]
57	str     r1, [r2, #EMIF_TIMING1_VAL_OFFSET]
58
59	ldr	r1, [r0, #EMIF_SDRAM_TIMING_2]
60	str     r1, [r2, #EMIF_TIMING2_VAL_OFFSET]
61
62	ldr	r1, [r0, #EMIF_SDRAM_TIMING_3]
63	str     r1, [r2, #EMIF_TIMING3_VAL_OFFSET]
64
65	ldr	r1, [r0, #EMIF_POWER_MANAGEMENT_CONTROL]
66	str     r1, [r2, #EMIF_PMCR_VAL_OFFSET]
67
68	ldr	r1, [r0, #EMIF_POWER_MANAGEMENT_CTRL_SHDW]
69	str     r1, [r2, #EMIF_PMCR_SHDW_VAL_OFFSET]
70
71	ldr	r1, [r0, #EMIF_SDRAM_OUTPUT_IMPEDANCE_CALIBRATION_CONFIG]
72	str     r1, [r2, #EMIF_ZQCFG_VAL_OFFSET]
73
74	ldr	r1, [r0, #EMIF_DDR_PHY_CTRL_1]
75	str     r1, [r2, #EMIF_DDR_PHY_CTLR_1_OFFSET]
76
77	ldr	r1, [r0, #EMIF_COS_CONFIG]
78	str     r1, [r2, #EMIF_COS_CONFIG_OFFSET]
79
80	ldr	r1, [r0, #EMIF_PRIORITY_TO_CLASS_OF_SERVICE_MAPPING]
81	str     r1, [r2, #EMIF_PRIORITY_TO_COS_MAPPING_OFFSET]
82
83	ldr	r1, [r0, #EMIF_CONNECTION_ID_TO_CLASS_OF_SERVICE_1_MAPPING]
84	str     r1, [r2, #EMIF_CONNECT_ID_SERV_1_MAP_OFFSET]
85
86	ldr	r1, [r0, #EMIF_CONNECTION_ID_TO_CLASS_OF_SERVICE_2_MAPPING]
87	str     r1, [r2, #EMIF_CONNECT_ID_SERV_2_MAP_OFFSET]
88
89	ldr	r1, [r0, #EMIF_OCP_CONFIG]
90	str     r1, [r2, #EMIF_OCP_CONFIG_VAL_OFFSET]
91
92	ldr	r5, [r4, #EMIF_PM_CONFIG_OFFSET]
93	cmp	r5, #EMIF_SRAM_AM43_REG_LAYOUT
94	bne	emif_skip_save_extra_regs
95
96	ldr	r1, [r0, #EMIF_READ_WRITE_LEVELING_RAMP_CONTROL]
97	str     r1, [r2, #EMIF_RD_WR_LEVEL_RAMP_CTRL_OFFSET]
98
99	ldr	r1, [r0, #EMIF_READ_WRITE_EXECUTION_THRESHOLD]
100	str     r1, [r2, #EMIF_RD_WR_EXEC_THRESH_OFFSET]
101
102	ldr	r1, [r0, #EMIF_LPDDR2_NVM_TIMING]
103	str     r1, [r2, #EMIF_LPDDR2_NVM_TIM_OFFSET]
104
105	ldr	r1, [r0, #EMIF_LPDDR2_NVM_TIMING_SHDW]
106	str     r1, [r2, #EMIF_LPDDR2_NVM_TIM_SHDW_OFFSET]
107
108	ldr	r1, [r0, #EMIF_DLL_CALIB_CTRL]
109	str     r1, [r2, #EMIF_DLL_CALIB_CTRL_VAL_OFFSET]
110
111	ldr	r1, [r0, #EMIF_DLL_CALIB_CTRL_SHDW]
112	str     r1, [r2, #EMIF_DLL_CALIB_CTRL_VAL_SHDW_OFFSET]
113
114	/* Loop and save entire block of emif phy regs */
115	mov	r5, #0x0
116	add	r4, r2, #EMIF_EXT_PHY_CTRL_VALS_OFFSET
117	add	r3, r0, #EMIF_EXT_PHY_CTRL_1
118ddr_phy_ctrl_save:
119	ldr	r1, [r3, r5]
120	str	r1, [r4, r5]
121	add	r5, r5, #0x4
122	cmp	r5, #AM43XX_EMIF_PHY_CTRL_REG_COUNT
123	bne	ddr_phy_ctrl_save
124
125emif_skip_save_extra_regs:
126	ldmfd	sp!, {r4 - r11, pc}	@ restore regs and return
127ENDPROC(ti_emif_save_context)
128
129/*
130 * void ti_emif_restore_context(void)
131 *
132 * Used during resume to restore the context of all required EMIF registers
133 * from local memory after the EMIF has lost context during a sleep transition.
134 * Operates on the PHYSICAL address of the EMIF.
135 */
136ENTRY(ti_emif_restore_context)
137	adr	r4, ti_emif_pm_sram_data
138	ldr	r0, [r4, #EMIF_PM_BASE_ADDR_PHYS_OFFSET]
139	ldr	r2, [r4, #EMIF_PM_REGS_PHYS_OFFSET]
140
141	/* Config EMIF Timings */
142	ldr     r1, [r2, #EMIF_DDR_PHY_CTLR_1_OFFSET]
143	str	r1, [r0, #EMIF_DDR_PHY_CTRL_1]
144	str	r1, [r0, #EMIF_DDR_PHY_CTRL_1_SHDW]
145
146	ldr     r1, [r2, #EMIF_TIMING1_VAL_OFFSET]
147	str	r1, [r0, #EMIF_SDRAM_TIMING_1]
148	str	r1, [r0, #EMIF_SDRAM_TIMING_1_SHDW]
149
150	ldr     r1, [r2, #EMIF_TIMING2_VAL_OFFSET]
151	str	r1, [r0, #EMIF_SDRAM_TIMING_2]
152	str	r1, [r0, #EMIF_SDRAM_TIMING_2_SHDW]
153
154	ldr     r1, [r2, #EMIF_TIMING3_VAL_OFFSET]
155	str	r1, [r0, #EMIF_SDRAM_TIMING_3]
156	str	r1, [r0, #EMIF_SDRAM_TIMING_3_SHDW]
157
158	ldr     r1, [r2, #EMIF_REF_CTRL_VAL_OFFSET]
159	str	r1, [r0, #EMIF_SDRAM_REFRESH_CONTROL]
160	str	r1, [r0, #EMIF_SDRAM_REFRESH_CTRL_SHDW]
161
162	ldr     r1, [r2, #EMIF_PMCR_VAL_OFFSET]
163	str	r1, [r0, #EMIF_POWER_MANAGEMENT_CONTROL]
164
165	ldr     r1, [r2, #EMIF_PMCR_SHDW_VAL_OFFSET]
166	str	r1, [r0, #EMIF_POWER_MANAGEMENT_CTRL_SHDW]
167
168	ldr     r1, [r2, #EMIF_COS_CONFIG_OFFSET]
169	str	r1, [r0, #EMIF_COS_CONFIG]
170
171	ldr     r1, [r2, #EMIF_PRIORITY_TO_COS_MAPPING_OFFSET]
172	str	r1, [r0, #EMIF_PRIORITY_TO_CLASS_OF_SERVICE_MAPPING]
173
174	ldr	r1, [r2, #EMIF_CONNECT_ID_SERV_1_MAP_OFFSET]
175	str	r1, [r0, #EMIF_CONNECTION_ID_TO_CLASS_OF_SERVICE_1_MAPPING]
176
177	ldr     r1, [r2, #EMIF_CONNECT_ID_SERV_2_MAP_OFFSET]
178	str	r1, [r0, #EMIF_CONNECTION_ID_TO_CLASS_OF_SERVICE_2_MAPPING]
179
180	ldr     r1, [r2, #EMIF_OCP_CONFIG_VAL_OFFSET]
181	str	r1, [r0, #EMIF_OCP_CONFIG]
182
183	ldr	r5, [r4, #EMIF_PM_CONFIG_OFFSET]
184	cmp	r5, #EMIF_SRAM_AM43_REG_LAYOUT
185	bne	emif_skip_restore_extra_regs
186
187	ldr     r1, [r2, #EMIF_RD_WR_LEVEL_RAMP_CTRL_OFFSET]
188	str	r1, [r0, #EMIF_READ_WRITE_LEVELING_RAMP_CONTROL]
189
190	ldr     r1, [r2, #EMIF_RD_WR_EXEC_THRESH_OFFSET]
191	str	r1, [r0, #EMIF_READ_WRITE_EXECUTION_THRESHOLD]
192
193	ldr     r1, [r2, #EMIF_LPDDR2_NVM_TIM_OFFSET]
194	str	r1, [r0, #EMIF_LPDDR2_NVM_TIMING]
195
196	ldr     r1, [r2, #EMIF_LPDDR2_NVM_TIM_SHDW_OFFSET]
197	str	r1, [r0, #EMIF_LPDDR2_NVM_TIMING_SHDW]
198
199	ldr     r1, [r2, #EMIF_DLL_CALIB_CTRL_VAL_OFFSET]
200	str	r1, [r0, #EMIF_DLL_CALIB_CTRL]
201
202	ldr     r1, [r2, #EMIF_DLL_CALIB_CTRL_VAL_SHDW_OFFSET]
203	str	r1, [r0, #EMIF_DLL_CALIB_CTRL_SHDW]
204
205	ldr     r1, [r2, #EMIF_ZQCFG_VAL_OFFSET]
206	str	r1, [r0, #EMIF_SDRAM_OUTPUT_IMPEDANCE_CALIBRATION_CONFIG]
207
208	/* Loop and restore entire block of emif phy regs */
209	mov	r5, #0x0
210	/* Load ti_emif_regs_amx3 + EMIF_EXT_PHY_CTRL_VALS_OFFSET for address
211	 * to phy register save space
212	 */
213	add	r3, r2, #EMIF_EXT_PHY_CTRL_VALS_OFFSET
214	add	r4, r0, #EMIF_EXT_PHY_CTRL_1
215ddr_phy_ctrl_restore:
216	ldr	r1, [r3, r5]
217	str	r1, [r4, r5]
218	add	r5, r5, #0x4
219	cmp	r5, #AM43XX_EMIF_PHY_CTRL_REG_COUNT
220	bne	ddr_phy_ctrl_restore
221
222emif_skip_restore_extra_regs:
223	/*
224	 * Output impedence calib needed only for DDR3
225	 * but since the initial state of this will be
226	 * disabled for DDR2 no harm in restoring the
227	 * old configuration
228	 */
229	ldr     r1, [r2, #EMIF_ZQCFG_VAL_OFFSET]
230	str	r1, [r0, #EMIF_SDRAM_OUTPUT_IMPEDANCE_CALIBRATION_CONFIG]
231
232	/* Write to sdcfg last for DDR2 only */
233	ldr	r1, [r2, #EMIF_SDCFG_VAL_OFFSET]
234	and	r2, r1, #SDRAM_TYPE_MASK
235	cmp	r2, #EMIF_SDCFG_TYPE_DDR2
236	streq	r1, [r0, #EMIF_SDRAM_CONFIG]
237
238	mov	pc, lr
239ENDPROC(ti_emif_restore_context)
240
241/*
242 * void ti_emif_run_hw_leveling(void)
243 *
244 * Used during resume to run hardware leveling again and restore the
245 * configuration of the EMIF PHY, only for DDR3.
246 */
247ENTRY(ti_emif_run_hw_leveling)
248	adr	r4, ti_emif_pm_sram_data
249	ldr	r0, [r4, #EMIF_PM_BASE_ADDR_PHYS_OFFSET]
250
251	ldr	r3, [r0, #EMIF_READ_WRITE_LEVELING_CONTROL]
252	orr	r3, r3, #RDWRLVLFULL_START
253	ldr	r2, [r0, #EMIF_SDRAM_CONFIG]
254	and	r2, r2, #SDRAM_TYPE_MASK
255	cmp	r2, #EMIF_SDCFG_TYPE_DDR3
256	bne	skip_hwlvl
257
258	str	r3, [r0, #EMIF_READ_WRITE_LEVELING_CONTROL]
259
260	/*
261	 * If EMIF registers are touched during initial stage of HW
262	 * leveling sequence there will be an L3 NOC timeout error issued
263	 * as the EMIF will not respond, which is not fatal, but it is
264	 * avoidable. This small wait loop is enough time for this condition
265	 * to clear, even at worst case of CPU running at max speed of 1Ghz.
266	 */
267	mov	r2, #0x2000
2681:
269	subs	r2, r2, #0x1
270	bne	1b
271
272	/* Bit clears when operation is complete */
2732:	ldr     r1, [r0, #EMIF_READ_WRITE_LEVELING_CONTROL]
274	tst     r1, #RDWRLVLFULL_START
275	bne     2b
276
277skip_hwlvl:
278	mov	pc, lr
279ENDPROC(ti_emif_run_hw_leveling)
280
281/*
282 * void ti_emif_enter_sr(void)
283 *
284 * Programs the EMIF to tell the SDRAM to enter into self-refresh
285 * mode during a sleep transition. Operates on the VIRTUAL address
286 * of the EMIF.
287 */
288ENTRY(ti_emif_enter_sr)
289	stmfd   sp!, {r4 - r11, lr}     @ save registers on stack
290
291	adr	r4, ti_emif_pm_sram_data
292	ldr	r0, [r4, #EMIF_PM_BASE_ADDR_VIRT_OFFSET]
293	ldr	r2, [r4, #EMIF_PM_REGS_VIRT_OFFSET]
294
295	ldr	r1, [r0, #EMIF_POWER_MANAGEMENT_CONTROL]
296	bic	r1, r1, #EMIF_POWER_MGMT_SELF_REFRESH_MODE_MASK
297	orr	r1, r1, #EMIF_POWER_MGMT_SELF_REFRESH_MODE
298	str	r1, [r0, #EMIF_POWER_MANAGEMENT_CONTROL]
299
300	ldmfd	sp!, {r4 - r11, pc}	@ restore regs and return
301ENDPROC(ti_emif_enter_sr)
302
303/*
304 * void ti_emif_exit_sr(void)
305 *
306 * Programs the EMIF to tell the SDRAM to exit self-refresh mode
307 * after a sleep transition. Operates on the PHYSICAL address of
308 * the EMIF.
309 */
310ENTRY(ti_emif_exit_sr)
311	adr	r4, ti_emif_pm_sram_data
312	ldr	r0, [r4, #EMIF_PM_BASE_ADDR_PHYS_OFFSET]
313	ldr	r2, [r4, #EMIF_PM_REGS_PHYS_OFFSET]
314
315	/*
316	 * Toggle EMIF to exit refresh mode:
317	 * if EMIF lost context, PWR_MGT_CTRL is currently 0, writing disable
318	 *   (0x0), wont do diddly squat! so do a toggle from SR(0x2) to disable
319	 *   (0x0) here.
320	 * *If* EMIF did not lose context, nothing broken as we write the same
321	 *   value(0x2) to reg before we write a disable (0x0).
322	 */
323	ldr	r1, [r2, #EMIF_PMCR_VAL_OFFSET]
324	bic	r1, r1, #EMIF_POWER_MGMT_SELF_REFRESH_MODE_MASK
325	orr	r1, r1, #EMIF_POWER_MGMT_SELF_REFRESH_MODE
326	str	r1, [r0, #EMIF_POWER_MANAGEMENT_CONTROL]
327	bic	r1, r1, #EMIF_POWER_MGMT_SELF_REFRESH_MODE_MASK
328	str	r1, [r0, #EMIF_POWER_MANAGEMENT_CONTROL]
329
330        /* Wait for EMIF to become ready */
3311:	ldr     r1, [r0, #EMIF_STATUS]
332	tst     r1, #EMIF_STATUS_READY
333	beq     1b
334
335	mov	pc, lr
336ENDPROC(ti_emif_exit_sr)
337
338/*
339 * void ti_emif_abort_sr(void)
340 *
341 * Disables self-refresh after a failed transition to a low-power
342 * state so the kernel can jump back to DDR and follow abort path.
343 * Operates on the VIRTUAL address of the EMIF.
344 */
345ENTRY(ti_emif_abort_sr)
346	stmfd   sp!, {r4 - r11, lr}     @ save registers on stack
347
348	adr	r4, ti_emif_pm_sram_data
349	ldr	r0, [r4, #EMIF_PM_BASE_ADDR_VIRT_OFFSET]
350	ldr	r2, [r4, #EMIF_PM_REGS_VIRT_OFFSET]
351
352	ldr	r1, [r2, #EMIF_PMCR_VAL_OFFSET]
353	bic	r1, r1, #EMIF_POWER_MGMT_SELF_REFRESH_MODE_MASK
354	str	r1, [r0, #EMIF_POWER_MANAGEMENT_CONTROL]
355
356	/* Wait for EMIF to become ready */
3571:	ldr     r1, [r0, #EMIF_STATUS]
358	tst     r1, #EMIF_STATUS_READY
359	beq     1b
360
361	ldmfd	sp!, {r4 - r11, pc}	@ restore regs and return
362ENDPROC(ti_emif_abort_sr)
363
364	.align 3
365ENTRY(ti_emif_pm_sram_data)
366	.space EMIF_PM_DATA_SIZE
367ENTRY(ti_emif_sram_sz)
368        .word   . - ti_emif_save_context
369