arch/arm/mach-omap2/prm44xx.c

   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);