xref: /openbmc/linux/arch/arm/mach-omap2/prm44xx.c (revision 05bcf503)
1 /*
2  * OMAP4 PRM module functions
3  *
4  * Copyright (C) 2011 Texas Instruments, Inc.
5  * Copyright (C) 2010 Nokia Corporation
6  * Benoît Cousson
7  * Paul Walmsley
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/delay.h>
16 #include <linux/errno.h>
17 #include <linux/err.h>
18 #include <linux/io.h>
19 
20 #include <plat/prcm.h>
21 
22 #include "soc.h"
23 #include "iomap.h"
24 #include "common.h"
25 #include "vp.h"
26 #include "prm44xx.h"
27 #include "prm-regbits-44xx.h"
28 #include "prcm44xx.h"
29 #include "prminst44xx.h"
30 
31 static const struct omap_prcm_irq omap4_prcm_irqs[] = {
32 	OMAP_PRCM_IRQ("wkup",   0,      0),
33 	OMAP_PRCM_IRQ("io",     9,      1),
34 };
35 
36 static struct omap_prcm_irq_setup omap4_prcm_irq_setup = {
37 	.ack			= OMAP4_PRM_IRQSTATUS_MPU_OFFSET,
38 	.mask			= OMAP4_PRM_IRQENABLE_MPU_OFFSET,
39 	.nr_regs		= 2,
40 	.irqs			= omap4_prcm_irqs,
41 	.nr_irqs		= ARRAY_SIZE(omap4_prcm_irqs),
42 	.irq			= 11 + OMAP44XX_IRQ_GIC_START,
43 	.read_pending_irqs	= &omap44xx_prm_read_pending_irqs,
44 	.ocp_barrier		= &omap44xx_prm_ocp_barrier,
45 	.save_and_clear_irqen	= &omap44xx_prm_save_and_clear_irqen,
46 	.restore_irqen		= &omap44xx_prm_restore_irqen,
47 };
48 
49 /* PRM low-level functions */
50 
51 /* Read a register in a CM/PRM instance in the PRM module */
52 u32 omap4_prm_read_inst_reg(s16 inst, u16 reg)
53 {
54 	return __raw_readl(OMAP44XX_PRM_REGADDR(inst, reg));
55 }
56 
57 /* Write into a register in a CM/PRM instance in the PRM module */
58 void omap4_prm_write_inst_reg(u32 val, s16 inst, u16 reg)
59 {
60 	__raw_writel(val, OMAP44XX_PRM_REGADDR(inst, reg));
61 }
62 
63 /* Read-modify-write a register in a PRM module. Caller must lock */
64 u32 omap4_prm_rmw_inst_reg_bits(u32 mask, u32 bits, s16 inst, s16 reg)
65 {
66 	u32 v;
67 
68 	v = omap4_prm_read_inst_reg(inst, reg);
69 	v &= ~mask;
70 	v |= bits;
71 	omap4_prm_write_inst_reg(v, inst, reg);
72 
73 	return v;
74 }
75 
76 /* PRM VP */
77 
78 /*
79  * struct omap4_vp - OMAP4 VP register access description.
80  * @irqstatus_mpu: offset to IRQSTATUS_MPU register for VP
81  * @tranxdone_status: VP_TRANXDONE_ST bitmask in PRM_IRQSTATUS_MPU reg
82  */
83 struct omap4_vp {
84 	u32 irqstatus_mpu;
85 	u32 tranxdone_status;
86 };
87 
88 static struct omap4_vp omap4_vp[] = {
89 	[OMAP4_VP_VDD_MPU_ID] = {
90 		.irqstatus_mpu = OMAP4_PRM_IRQSTATUS_MPU_2_OFFSET,
91 		.tranxdone_status = OMAP4430_VP_MPU_TRANXDONE_ST_MASK,
92 	},
93 	[OMAP4_VP_VDD_IVA_ID] = {
94 		.irqstatus_mpu = OMAP4_PRM_IRQSTATUS_MPU_OFFSET,
95 		.tranxdone_status = OMAP4430_VP_IVA_TRANXDONE_ST_MASK,
96 	},
97 	[OMAP4_VP_VDD_CORE_ID] = {
98 		.irqstatus_mpu = OMAP4_PRM_IRQSTATUS_MPU_OFFSET,
99 		.tranxdone_status = OMAP4430_VP_CORE_TRANXDONE_ST_MASK,
100 	},
101 };
102 
103 u32 omap4_prm_vp_check_txdone(u8 vp_id)
104 {
105 	struct omap4_vp *vp = &omap4_vp[vp_id];
106 	u32 irqstatus;
107 
108 	irqstatus = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
109 						OMAP4430_PRM_OCP_SOCKET_INST,
110 						vp->irqstatus_mpu);
111 	return irqstatus & vp->tranxdone_status;
112 }
113 
114 void omap4_prm_vp_clear_txdone(u8 vp_id)
115 {
116 	struct omap4_vp *vp = &omap4_vp[vp_id];
117 
118 	omap4_prminst_write_inst_reg(vp->tranxdone_status,
119 				     OMAP4430_PRM_PARTITION,
120 				     OMAP4430_PRM_OCP_SOCKET_INST,
121 				     vp->irqstatus_mpu);
122 };
123 
124 u32 omap4_prm_vcvp_read(u8 offset)
125 {
126 	return omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
127 					   OMAP4430_PRM_DEVICE_INST, offset);
128 }
129 
130 void omap4_prm_vcvp_write(u32 val, u8 offset)
131 {
132 	omap4_prminst_write_inst_reg(val, OMAP4430_PRM_PARTITION,
133 				     OMAP4430_PRM_DEVICE_INST, offset);
134 }
135 
136 u32 omap4_prm_vcvp_rmw(u32 mask, u32 bits, u8 offset)
137 {
138 	return omap4_prminst_rmw_inst_reg_bits(mask, bits,
139 					       OMAP4430_PRM_PARTITION,
140 					       OMAP4430_PRM_DEVICE_INST,
141 					       offset);
142 }
143 
144 static inline u32 _read_pending_irq_reg(u16 irqen_offs, u16 irqst_offs)
145 {
146 	u32 mask, st;
147 
148 	/* XXX read mask from RAM? */
149 	mask = omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
150 				       irqen_offs);
151 	st = omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST, irqst_offs);
152 
153 	return mask & st;
154 }
155 
156 /**
157  * omap44xx_prm_read_pending_irqs - read pending PRM MPU IRQs into @events
158  * @events: ptr to two consecutive u32s, preallocated by caller
159  *
160  * Read PRM_IRQSTATUS_MPU* bits, AND'ed with the currently-enabled PRM
161  * MPU IRQs, and store the result into the two u32s pointed to by @events.
162  * No return value.
163  */
164 void omap44xx_prm_read_pending_irqs(unsigned long *events)
165 {
166 	events[0] = _read_pending_irq_reg(OMAP4_PRM_IRQENABLE_MPU_OFFSET,
167 					  OMAP4_PRM_IRQSTATUS_MPU_OFFSET);
168 
169 	events[1] = _read_pending_irq_reg(OMAP4_PRM_IRQENABLE_MPU_2_OFFSET,
170 					  OMAP4_PRM_IRQSTATUS_MPU_2_OFFSET);
171 }
172 
173 /**
174  * omap44xx_prm_ocp_barrier - force buffered MPU writes to the PRM to complete
175  *
176  * Force any buffered writes to the PRM IP block to complete.  Needed
177  * by the PRM IRQ handler, which reads and writes directly to the IP
178  * block, to avoid race conditions after acknowledging or clearing IRQ
179  * bits.  No return value.
180  */
181 void omap44xx_prm_ocp_barrier(void)
182 {
183 	omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
184 				OMAP4_REVISION_PRM_OFFSET);
185 }
186 
187 /**
188  * omap44xx_prm_save_and_clear_irqen - save/clear PRM_IRQENABLE_MPU* regs
189  * @saved_mask: ptr to a u32 array to save IRQENABLE bits
190  *
191  * Save the PRM_IRQENABLE_MPU and PRM_IRQENABLE_MPU_2 registers to
192  * @saved_mask.  @saved_mask must be allocated by the caller.
193  * Intended to be used in the PRM interrupt handler suspend callback.
194  * The OCP barrier is needed to ensure the write to disable PRM
195  * interrupts reaches the PRM before returning; otherwise, spurious
196  * interrupts might occur.  No return value.
197  */
198 void omap44xx_prm_save_and_clear_irqen(u32 *saved_mask)
199 {
200 	saved_mask[0] =
201 		omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
202 					OMAP4_PRM_IRQSTATUS_MPU_OFFSET);
203 	saved_mask[1] =
204 		omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
205 					OMAP4_PRM_IRQSTATUS_MPU_2_OFFSET);
206 
207 	omap4_prm_write_inst_reg(0, OMAP4430_PRM_OCP_SOCKET_INST,
208 				 OMAP4_PRM_IRQENABLE_MPU_OFFSET);
209 	omap4_prm_write_inst_reg(0, OMAP4430_PRM_OCP_SOCKET_INST,
210 				 OMAP4_PRM_IRQENABLE_MPU_2_OFFSET);
211 
212 	/* OCP barrier */
213 	omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
214 				OMAP4_REVISION_PRM_OFFSET);
215 }
216 
217 /**
218  * omap44xx_prm_restore_irqen - set PRM_IRQENABLE_MPU* registers from args
219  * @saved_mask: ptr to a u32 array of IRQENABLE bits saved previously
220  *
221  * Restore the PRM_IRQENABLE_MPU and PRM_IRQENABLE_MPU_2 registers from
222  * @saved_mask.  Intended to be used in the PRM interrupt handler resume
223  * callback to restore values saved by omap44xx_prm_save_and_clear_irqen().
224  * No OCP barrier should be needed here; any pending PRM interrupts will fire
225  * once the writes reach the PRM.  No return value.
226  */
227 void omap44xx_prm_restore_irqen(u32 *saved_mask)
228 {
229 	omap4_prm_write_inst_reg(saved_mask[0], OMAP4430_PRM_OCP_SOCKET_INST,
230 				 OMAP4_PRM_IRQENABLE_MPU_OFFSET);
231 	omap4_prm_write_inst_reg(saved_mask[1], OMAP4430_PRM_OCP_SOCKET_INST,
232 				 OMAP4_PRM_IRQENABLE_MPU_2_OFFSET);
233 }
234 
235 /**
236  * omap44xx_prm_reconfigure_io_chain - clear latches and reconfigure I/O chain
237  *
238  * Clear any previously-latched I/O wakeup events and ensure that the
239  * I/O wakeup gates are aligned with the current mux settings.  Works
240  * by asserting WUCLKIN, waiting for WUCLKOUT to be asserted, and then
241  * deasserting WUCLKIN and waiting for WUCLKOUT to be deasserted.
242  * No return value. XXX Are the final two steps necessary?
243  */
244 void omap44xx_prm_reconfigure_io_chain(void)
245 {
246 	int i = 0;
247 
248 	/* Trigger WUCLKIN enable */
249 	omap4_prm_rmw_inst_reg_bits(OMAP4430_WUCLK_CTRL_MASK,
250 				    OMAP4430_WUCLK_CTRL_MASK,
251 				    OMAP4430_PRM_DEVICE_INST,
252 				    OMAP4_PRM_IO_PMCTRL_OFFSET);
253 	omap_test_timeout(
254 		(((omap4_prm_read_inst_reg(OMAP4430_PRM_DEVICE_INST,
255 					   OMAP4_PRM_IO_PMCTRL_OFFSET) &
256 		   OMAP4430_WUCLK_STATUS_MASK) >>
257 		  OMAP4430_WUCLK_STATUS_SHIFT) == 1),
258 		MAX_IOPAD_LATCH_TIME, i);
259 	if (i == MAX_IOPAD_LATCH_TIME)
260 		pr_warn("PRM: I/O chain clock line assertion timed out\n");
261 
262 	/* Trigger WUCLKIN disable */
263 	omap4_prm_rmw_inst_reg_bits(OMAP4430_WUCLK_CTRL_MASK, 0x0,
264 				    OMAP4430_PRM_DEVICE_INST,
265 				    OMAP4_PRM_IO_PMCTRL_OFFSET);
266 	omap_test_timeout(
267 		(((omap4_prm_read_inst_reg(OMAP4430_PRM_DEVICE_INST,
268 					   OMAP4_PRM_IO_PMCTRL_OFFSET) &
269 		   OMAP4430_WUCLK_STATUS_MASK) >>
270 		  OMAP4430_WUCLK_STATUS_SHIFT) == 0),
271 		MAX_IOPAD_LATCH_TIME, i);
272 	if (i == MAX_IOPAD_LATCH_TIME)
273 		pr_warn("PRM: I/O chain clock line deassertion timed out\n");
274 
275 	return;
276 }
277 
278 /**
279  * omap44xx_prm_enable_io_wakeup - enable wakeup events from I/O wakeup latches
280  *
281  * Activates the I/O wakeup event latches and allows events logged by
282  * those latches to signal a wakeup event to the PRCM.  For I/O wakeups
283  * to occur, WAKEUPENABLE bits must be set in the pad mux registers, and
284  * omap44xx_prm_reconfigure_io_chain() must be called.  No return value.
285  */
286 static void __init omap44xx_prm_enable_io_wakeup(void)
287 {
288 	omap4_prm_rmw_inst_reg_bits(OMAP4430_GLOBAL_WUEN_MASK,
289 				    OMAP4430_GLOBAL_WUEN_MASK,
290 				    OMAP4430_PRM_DEVICE_INST,
291 				    OMAP4_PRM_IO_PMCTRL_OFFSET);
292 }
293 
294 static int __init omap4xxx_prcm_init(void)
295 {
296 	if (cpu_is_omap44xx()) {
297 		omap44xx_prm_enable_io_wakeup();
298 		return omap_prcm_register_chain_handler(&omap4_prcm_irq_setup);
299 	}
300 	return 0;
301 }
302 subsys_initcall(omap4xxx_prcm_init);
303