/*************************************************************************** * __________ __ ___. * Open \______ \ ____ ____ | | _\_ |__ _______ ___ * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ * \/ \/ \/ \/ \/ * $Id$ * * Copyright (C) 2010 by Michael Sevakis * * i.MX31 DVFS and DPTC drivers * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY * KIND, either express or implied. * ****************************************************************************/ #include "config.h" #include "system.h" #include "logf.h" #include "mc13783.h" #include "iomuxc-imx31.h" #include "ccm-imx31.h" #include "avic-imx31.h" #include "dvfs_dptc-imx31.h" #include "dvfs_dptc_tables-target.h" /* Most of the code in here is based upon the Linux BSP provided by Freescale * Copyright 2004-2008 Freescale Semiconductor, Inc. All Rights Reserved. */ /* The current DVFS index level */ static volatile unsigned int dvfs_level = DVFS_LEVEL_DEFAULT; /* The current DPTC working point */ static volatile unsigned int dptc_wp = DPTC_WP_DEFAULT; static void update_dptc_counts(unsigned int level, unsigned int wp) { int oldlevel = disable_irq_save(); const struct dptc_dcvr_table_entry *entry = &dptc_dcvr_table[level][wp]; CCM_DCVR0 = entry->dcvr0; CCM_DCVR1 = entry->dcvr1; CCM_DCVR2 = entry->dcvr2; CCM_DCVR3 = entry->dcvr3; restore_irq(oldlevel); } static uint32_t check_regulator_setting(uint32_t setting) { /* Simply a safety check *in case* table gets scrambled */ if (setting < VOLTAGE_SETTING_MIN) setting = VOLTAGE_SETTING_MIN; else if (setting > VOLTAGE_SETTING_MAX) setting = VOLTAGE_SETTING_MAX; return setting; } /** DVFS **/ static bool dvfs_running = false; /* Has driver enabled DVFS? */ /* Request tracking since boot */ unsigned int dvfs_nr_dn = 0; unsigned int dvfs_nr_up = 0; unsigned int dvfs_nr_pnc = 0; unsigned int dvfs_nr_no = 0; static void dvfs_stop(void); /* Wait for the UPDTEN flag to be set so that all bits may be written */ static inline void wait_for_dvfs_update_en(void) { while (!(CCM_PMCR0 & CCM_PMCR0_UPDTEN)); } static void do_dvfs_update(unsigned int level, bool in_isr) { const struct dvfs_clock_table_entry *setting = &dvfs_clock_table[level]; unsigned long pmcr0 = CCM_PMCR0; if (pmcr0 & CCM_PMCR0_DPTEN) { /* Ignore voltage change request from DPTC. Voltage is *not* valid. */ pmcr0 &= ~CCM_PMCR0_DPVCR; } pmcr0 &= ~CCM_PMCR0_VSCNT; if (level < ((pmcr0 & CCM_PMCR0_DVSUP) >> CCM_PMCR0_DVSUP_POS)) { pmcr0 |= CCM_PMCR0_UDSC; /* Up scaling, increase */ pmcr0 |= setting->vscnt << CCM_PMCR0_VSCNT_POS; } else { pmcr0 &= ~CCM_PMCR0_UDSC; /* Down scaling, decrease */ pmcr0 |= 0x1 << CCM_PMCR0_VSCNT_POS; } /* DVSUP (new frequency index) setup */ pmcr0 = (pmcr0 & ~CCM_PMCR0_DVSUP) | (level << CCM_PMCR0_DVSUP_POS); dvfs_level = level; if ((setting->pll_num << CCM_PMCR0_DFSUP_MCUPLL_POS) ^ (pmcr0 & CCM_PMCR0_DFSUP_MCUPLL)) { /* Update pll and post-dividers. */ pmcr0 ^= CCM_PMCR0_DFSUP_MCUPLL; pmcr0 &= ~CCM_PMCR0_DFSUP_POST_DIVIDERS; } else { /* Post-dividers update only */ pmcr0 |= CCM_PMCR0_DFSUP_POST_DIVIDERS; } CCM_PMCR0 = pmcr0; /* Note: changes to frequency with ints unmaked seem to cause spurious * DVFS interrupts with value CCM_PMCR0_FSVAI_NO_INT. These aren't * supposed to happen. Only do the lengthy delay with them enabled iff * called from the IRQ handler. */ if (in_isr) enable_irq(); udelay(100); /* Software wait for voltage ramp-up */ if (in_isr) disable_irq(); CCM_PDR0 = setting->pdr_val; if (!(pmcr0 & CCM_PMCR0_DFSUP_POST_DIVIDERS)) { /* Update the PLL settings */ if (pmcr0 & CCM_PMCR0_DFSUP_MCUPLL) CCM_MPCTL = setting->pll_val; else CCM_SPCTL = setting->pll_val; } cpu_frequency = ccm_get_mcu_clk(); if (pmcr0 & CCM_PMCR0_DPTEN) { update_dptc_counts(level, dptc_wp); /* Enable DPTC to request voltage changes. Voltage is valid. */ CCM_PMCR0 |= CCM_PMCR0_DPVCR; udelay(2); CCM_PMCR0 |= CCM_PMCR0_DPVV; } } /* Start DVFS, change the set point and stop it */ static void set_current_dvfs_level(unsigned int level) { int oldlevel = disable_irq_save(); CCM_PMCR0 |= CCM_PMCR0_DVFEN; wait_for_dvfs_update_en(); do_dvfs_update(level, false); wait_for_dvfs_update_en(); CCM_PMCR0 &= ~CCM_PMCR0_DVFEN; restore_irq(oldlevel); } /* DVFS Interrupt handler */ static void __attribute__((used)) dvfs_int(void) { unsigned long pmcr0 = CCM_PMCR0; unsigned long fsvai = pmcr0 & CCM_PMCR0_FSVAI; unsigned int level = (pmcr0 & CCM_PMCR0_DVSUP) >> CCM_PMCR0_DVSUP_POS; if (pmcr0 & CCM_PMCR0_FSVAIM) return; /* Do nothing. DVFS interrupt is masked. */ if (!(pmcr0 & CCM_PMCR0_UPDTEN)) return; /* Do nothing. DVFS didn't finish previous flow update. */ switch (fsvai) { case CCM_PMCR0_FSVAI_DECREASE: if (level >= DVFS_NUM_LEVELS - 1) return; /* DVFS already at lowest level */ /* Upon the DECREASE event, the frequency will be changed to the next * higher state index. */ while (((1u << ++level) & DVFS_LEVEL_MASK) == 0); dvfs_nr_dn++; break; /* Single-step frequency increase */ case CCM_PMCR0_FSVAI_INCREASE: if (level == 0) return; /* DVFS already at highest level */ /* Upon the INCREASE event, the frequency will be changed to the next * lower state index. */ while (((1u << --level) & DVFS_LEVEL_MASK) == 0); dvfs_nr_up++; break; /* Right to highest if panic */ case CCM_PMCR0_FSVAI_INCREASE_NOW: if (level == 0) return; /* DVFS already at highest level */ /* Upon the INCREASE_NOW event, the frequency will be increased to * the maximum (index 0). */ level = 0; dvfs_nr_pnc++; break; case CCM_PMCR0_FSVAI_NO_INT: dvfs_nr_no++; return; /* Do nothing. Freq change is not required */ } /* end switch */ do_dvfs_update(level, true); } /* Interrupt vector for DVFS */ static __attribute__((naked, interrupt("IRQ"))) void CCM_DVFS_HANDLER(void) { /* Audio can glitch with the long udelay if nested IRQ isn't allowed. */ AVIC_NESTED_NI_CALL_PROLOGUE(INT_PRIO_DVFS, 32*4); asm volatile ("bl dvfs_int"); AVIC_NESTED_NI_CALL_EPILOGUE(32*4); } /* Initialize the DVFS hardware */ static void INIT_ATTR dvfs_init(void) { if (CCM_PMCR0 & CCM_PMCR0_DVFEN) { /* Turn it off first. Really, shouldn't happen though. */ dvfs_running = true; dvfs_stop(); } /* Combine SW1A and SW1B DVS pins for a possible five DVS levels * per working point. Four, MAXIMUM, are actually used, one for each * frequency. */ mc13783_set(MC13783_ARBITRATION_SWITCHERS, MC13783_SW1ABDVS); /* Set DVS speed to 25mV every 4us. */ mc13783_write_masked(MC13783_SWITCHERS4, MC13783_SW1ADVSSPEED_4US, MC13783_SW1ADVSSPEED); /* Set DVFS pins to functional outputs. Input mode and pad setting is * fixed in hardware. */ iomuxc_set_pin_mux(IOMUXC_DVFS0, IOMUXC_MUX_OUT_FUNCTIONAL | IOMUXC_MUX_IN_NONE); iomuxc_set_pin_mux(IOMUXC_DVFS1, IOMUXC_MUX_OUT_FUNCTIONAL | IOMUXC_MUX_IN_NONE); #ifndef DVFS_NO_PWRRDY /* Configure PWRRDY signal pin. */ imx31_regclr32(&GPIO1_GDIR, (1 << 5)); iomuxc_set_pin_mux(IOMUXC_GPIO1_5, IOMUXC_MUX_OUT_FUNCTIONAL | IOMUXC_MUX_IN_FUNCTIONAL); #endif /* Initialize DVFS signal weights and detection modes. */ int i; for (i = 0; i < 16; i++) { dvfs_set_lt_weight(i, lt_signals[i].weight); dvfs_set_lt_detect(i, lt_signals[i].detect); } /* Set up LTR0. */ imx31_regmod32(&CCM_LTR0, DVFS_UPTHR << CCM_LTR0_UPTHR_POS | DVFS_DNTHR << CCM_LTR0_DNTHR_POS | DVFS_DIV3CK << CCM_LTR0_DIV3CK_POS, CCM_LTR0_UPTHR | CCM_LTR0_DNTHR | CCM_LTR0_DIV3CK); /* Set up LTR1. */ imx31_regmod32(&CCM_LTR1, DVFS_DNCNT << CCM_LTR1_DNCNT_POS | DVFS_UPCNT << CCM_LTR1_UPCNT_POS | DVFS_PNCTHR << CCM_LTR1_PNCTHR_POS | CCM_LTR1_LTBRSR, CCM_LTR1_DNCNT | CCM_LTR1_UPCNT | CCM_LTR1_PNCTHR | CCM_LTR1_LTBRSR); /* Set up LTR2-- EMA configuration. */ imx31_regmod32(&CCM_LTR2, DVFS_EMAC << CCM_LTR2_EMAC_POS, CCM_LTR2_EMAC); /* DVFS interrupt goes to MCU. Mask load buffer full interrupt. */ imx31_regset32(&CCM_PMCR0, CCM_PMCR0_DVFIS | CCM_PMCR0_LBMI); /* Initialize current core PLL and dividers for default level. Assumes * clocking scheme has been set up appropriately in other init code. */ ccm_set_mcupll_and_pdr(dvfs_clock_table[DVFS_LEVEL_DEFAULT].pll_val, dvfs_clock_table[DVFS_LEVEL_DEFAULT].pdr_val); /* Set initial level and working point. */ set_current_dvfs_level(DVFS_LEVEL_DEFAULT); logf("DVFS: Initialized"); } /* Start the DVFS hardware */ static void dvfs_start(void) { int oldlevel; /* Have to wait at least 3 div3 clocks before enabling after being * stopped. */ udelay(1500); oldlevel = disable_irq_save(); if (!dvfs_running) { dvfs_running = true; /* Unmask DVFS interrupt source and enable DVFS. */ avic_enable_int(INT_CCM_DVFS, INT_TYPE_IRQ, INT_PRIO_DVFS, CCM_DVFS_HANDLER); CCM_PMCR0 = (CCM_PMCR0 & ~CCM_PMCR0_FSVAIM) | CCM_PMCR0_DVFEN; } restore_irq(oldlevel); logf("DVFS: started"); } /* Stop the DVFS hardware and return to default frequency */ static void dvfs_stop(void) { int oldlevel = disable_irq_save(); if (dvfs_running) { /* Mask DVFS interrupts. */ CCM_PMCR0 |= CCM_PMCR0_FSVAIM | CCM_PMCR0_LBMI; avic_disable_int(INT_CCM_DVFS); if (((CCM_PMCR0 & CCM_PMCR0_DVSUP) >> CCM_PMCR0_DVSUP_POS) != DVFS_LEVEL_DEFAULT) { /* Set default frequency level */ wait_for_dvfs_update_en(); do_dvfs_update(DVFS_LEVEL_DEFAULT, false); wait_for_dvfs_update_en(); } /* Disable DVFS. */ CCM_PMCR0 &= ~CCM_PMCR0_DVFEN; dvfs_running = false; } restore_irq(oldlevel); logf("DVFS: stopped"); } /** DPTC **/ /* Request tracking since boot */ static bool dptc_running = false; /* Has driver enabled DPTC? */ unsigned int dptc_nr_dn = 0; unsigned int dptc_nr_up = 0; unsigned int dptc_nr_pnc = 0; unsigned int dptc_nr_no = 0; static struct spi_transfer_desc dptc_pmic_xfer; /* Transfer descriptor */ static const unsigned char dptc_pmic_regs[2] = /* Register subaddresses */ { MC13783_SWITCHERS0, MC13783_SWITCHERS1 }; static uint32_t dptc_reg_shadows[2]; /* shadow regs */ static uint32_t dptc_regs_buf[2]; /* buffer for async write */ /* Enable DPTC and unmask interrupt. */ static void enable_dptc(void) { int oldlevel = disable_irq_save(); /* Enable DPTC, assert voltage change request. */ CCM_PMCR0 = (CCM_PMCR0 & ~CCM_PMCR0_PTVAIM) | CCM_PMCR0_DPTEN | CCM_PMCR0_DPVCR; udelay(2); /* Set voltage valid *after* setting change request */ CCM_PMCR0 |= CCM_PMCR0_DPVV; restore_irq(oldlevel); } /* Called after asynchronous PMIC write is completed */ static void dptc_transfer_done_callback(struct spi_transfer_desc *xfer) { if (xfer->count != 0) return; update_dptc_counts(dvfs_level, dptc_wp); if (dptc_running) enable_dptc(); } /* Handle the DPTC interrupt and sometimes the manual setting */ static void dptc_int(unsigned long pmcr0) { const union dvfs_dptc_voltage_table_entry *entry; uint32_t sw1a, sw1advs, sw1bdvs, sw1bstby; uint32_t switchers0, switchers1; int wp = dptc_wp; /* Mask DPTC interrupt and disable DPTC until the change request is * serviced. */ CCM_PMCR0 = (pmcr0 & ~CCM_PMCR0_DPTEN) | CCM_PMCR0_PTVAIM; switch (pmcr0 & CCM_PMCR0_PTVAI) { case CCM_PMCR0_PTVAI_DECREASE: wp++; dptc_nr_dn++; break; case CCM_PMCR0_PTVAI_INCREASE: wp--; dptc_nr_up++; break; case CCM_PMCR0_PTVAI_INCREASE_NOW: if (--wp > DPTC_WP_PANIC) wp = DPTC_WP_PANIC; dptc_nr_pnc++; break; case CCM_PMCR0_PTVAI_NO_INT: break; /* Just maintain at global level */ } if (wp < 0) wp = 0; else if (wp >= DPTC_NUM_WP) wp = DPTC_NUM_WP - 1; entry = &dvfs_dptc_voltage_table[wp]; sw1a = check_regulator_setting(entry->sw1a); sw1advs = check_regulator_setting(entry->sw1advs); sw1bdvs = check_regulator_setting(entry->sw1bdvs); sw1bstby = check_regulator_setting(entry->sw1bstby); switchers0 = dptc_reg_shadows[0] & ~(MC13783_SW1A | MC13783_SW1ADVS); dptc_regs_buf[0] = switchers0 | sw1a << MC13783_SW1A_POS | /* SW1A */ sw1advs << MC13783_SW1ADVS_POS; /* SW1ADVS */ switchers1 = dptc_reg_shadows[1] & ~(MC13783_SW1BDVS | MC13783_SW1BSTBY); dptc_regs_buf[1] = switchers1 | sw1bdvs << MC13783_SW1BDVS_POS | /* SW1BDVS */ sw1bstby << MC13783_SW1BSTBY_POS; /* SW1BSTBY */ dptc_wp = wp; mc13783_write_async(&dptc_pmic_xfer, dptc_pmic_regs, dptc_regs_buf, 2, dptc_transfer_done_callback); } static void dptc_new_wp(unsigned int wp) { dptc_wp = wp; /* "NO_INT" so the working point isn't incremented, just set. */ dptc_int((CCM_PMCR0 & ~CCM_PMCR0_PTVAI) | CCM_PMCR0_PTVAI_NO_INT); } /* Interrupt vector for DPTC */ static __attribute__((interrupt("IRQ"))) void CCM_CLK_HANDLER(void) { unsigned long pmcr0 = CCM_PMCR0; if ((pmcr0 & CCM_PMCR0_PTVAI) == CCM_PMCR0_PTVAI_NO_INT) dptc_nr_no++; dptc_int(pmcr0); } /* Initialize the DPTC hardware */ static void INIT_ATTR dptc_init(void) { /* Force DPTC off if running for some reason. */ imx31_regmod32(&CCM_PMCR0, CCM_PMCR0_PTVAIM, CCM_PMCR0_PTVAIM | CCM_PMCR0_DPTEN); /* Shadow the regulator registers */ mc13783_read_regs(dptc_pmic_regs, dptc_reg_shadows, 2); /* Set default, safe working point. */ dptc_new_wp(DPTC_WP_DEFAULT); /* Interrupt goes to MCU, specified reference circuits enabled when * DPTC is active. */ imx31_regset32(&CCM_PMCR0, CCM_PMCR0_PTVIS); imx31_regmod32(&CCM_PMCR0, DPTC_DRCE_MASK, CCM_PMCR0_DRCE0 | CCM_PMCR0_DRCE1 | CCM_PMCR0_DRCE2 | CCM_PMCR0_DRCE3); /* DPTC counting range = 256 system clocks */ imx31_regclr32(&CCM_PMCR0, CCM_PMCR0_DCR); logf("DPTC: Initialized"); } /* Start DPTC module */ static void dptc_start(void) { int oldlevel = disable_irq_save(); if (!dptc_running) { dptc_running = true; /* Enable DPTC and unmask interrupt. */ avic_enable_int(INT_CCM_CLK, INT_TYPE_IRQ, INT_PRIO_DPTC, CCM_CLK_HANDLER); update_dptc_counts(dvfs_level, dptc_wp); enable_dptc(); } restore_irq(oldlevel); logf("DPTC: started"); } /* Stop the DPTC hardware if running and go back to default working point */ static void dptc_stop(void) { int oldlevel = disable_irq_save(); if (dptc_running) { dptc_running = false; /* Disable DPTC and mask interrupt. */ CCM_PMCR0 = (CCM_PMCR0 & ~CCM_PMCR0_DPTEN) | CCM_PMCR0_PTVAIM; avic_disable_int(INT_CCM_CLK); /* Go back to default working point. */ dptc_new_wp(DPTC_WP_DEFAULT); } restore_irq(oldlevel); logf("DPTC: stopped"); } /** Main module interface **/ /* Initialize DVFS and DPTC */ void INIT_ATTR dvfs_dptc_init(void) { dptc_init(); dvfs_init(); } /* Start DVFS and DPTC */ void dvfs_dptc_start(void) { dvfs_start(); dptc_start(); } /* Stop DVFS and DPTC */ void dvfs_dptc_stop(void) { dptc_stop(); dvfs_stop(); } /* Set a signal load tracking weight */ void dvfs_set_lt_weight(enum DVFS_LT_SIGS index, unsigned long value) { volatile unsigned long *reg_p = &CCM_LTR2; unsigned int shift = 3 * index; if (index < 9) { reg_p = &CCM_LTR3; shift += 5; /* Bits 7:5, 10:8 ... 31:29 */ } else if (index < 16) { shift -= 16; /* Bits 13:11, 16:14 ... 31:29 */ } imx31_regmod32(reg_p, value << shift, 0x7 << shift); } /* Set a signal load detection mode */ void dvfs_set_lt_detect(enum DVFS_LT_SIGS index, bool edge) { unsigned long bit = 0; if ((unsigned)index < 13) bit = 1ul << (index + 3); else if ((unsigned)index < 16) bit = 1ul << (index + 29); imx31_regmod32(&CCM_LTR0, edge ? bit : 0, bit); } void dvfs_set_gp_bit(enum DVFS_DVGPS dvgp, bool assert) { if ((unsigned)dvgp <= 3) { unsigned long bit = 1ul << dvgp; imx31_regmod32(&CCM_PMCR1, assert ? bit : 0, bit); } } /* Turn the wait-for-interrupt monitoring on or off */ void dvfs_wfi_monitor(bool on) { imx31_regmod32(&CCM_PMCR0, on ? 0 : CCM_PMCR0_WFIM, CCM_PMCR0_WFIM); } /* Obtain the current core voltage setting, in millivolts 8-) */ unsigned int dvfs_dptc_get_voltage(void) { unsigned int v; int oldlevel = disable_irq_save(); v = dvfs_dptc_voltage_table[dptc_wp].sw[dvfs_level]; restore_irq(oldlevel); /* 25mV steps from 0.900V to 1.675V */ return v * 25 + 900; } /* Get the current DVFS level */ unsigned int dvfs_get_level(void) { return dvfs_level; } /* If DVFS is disabled, set the level explicitly */ void dvfs_set_level(unsigned int level) { int oldlevel = disable_irq_save(); unsigned int currlevel = (CCM_PMCR0 & CCM_PMCR0_DVSUP) >> CCM_PMCR0_DVSUP_POS; if (!dvfs_running && level < DVFS_NUM_LEVELS && level != currlevel) set_current_dvfs_level(level); restore_irq(oldlevel); } /* Get the current DPTC working point */ unsigned int dptc_get_wp(void) { return dptc_wp; } /* If DPTC is not running, set the working point explicitly */ void dptc_set_wp(unsigned int wp) { int oldlevel = disable_irq_save(); if (!dptc_running && wp < DPTC_NUM_WP) dptc_new_wp(wp); restore_irq(oldlevel); }