/* * OMAP3/4 - specific DPLL control functions * * Copyright (C) 2009-2010 Texas Instruments, Inc. * Copyright (C) 2009-2010 Nokia Corporation * * Written by Paul Walmsley * Testing and integration fixes by Jouni Högander * * 36xx support added by Vishwanath BS, Richard Woodruff, and Nishanth * Menon * * Parts of this code are based on code written by * Richard Woodruff, Tony Lindgren, Tuukka Tikkanen, Karthik Dasu * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include #include #include #include #include #include #include #include #include #include "soc.h" #include "clockdomain.h" #include "clock.h" #include "cm2xxx_3xxx.h" #include "cm-regbits-34xx.h" /* CM_AUTOIDLE_PLL*.AUTO_* bit values */ #define DPLL_AUTOIDLE_DISABLE 0x0 #define DPLL_AUTOIDLE_LOW_POWER_STOP 0x1 #define MAX_DPLL_WAIT_TRIES 1000000 /* Private functions */ /* _omap3_dpll_write_clken - write clken_bits arg to a DPLL's enable bits */ static void _omap3_dpll_write_clken(struct clk_hw_omap *clk, u8 clken_bits) { const struct dpll_data *dd; u32 v; dd = clk->dpll_data; v = __raw_readl(dd->control_reg); v &= ~dd->enable_mask; v |= clken_bits << __ffs(dd->enable_mask); __raw_writel(v, dd->control_reg); } /* _omap3_wait_dpll_status: wait for a DPLL to enter a specific state */ static int _omap3_wait_dpll_status(struct clk_hw_omap *clk, u8 state) { const struct dpll_data *dd; int i = 0; int ret = -EINVAL; const char *clk_name; dd = clk->dpll_data; clk_name = __clk_get_name(clk->hw.clk); state <<= __ffs(dd->idlest_mask); while (((__raw_readl(dd->idlest_reg) & dd->idlest_mask) != state) && i < MAX_DPLL_WAIT_TRIES) { i++; udelay(1); } if (i == MAX_DPLL_WAIT_TRIES) { printk(KERN_ERR "clock: %s failed transition to '%s'\n", clk_name, (state) ? "locked" : "bypassed"); } else { pr_debug("clock: %s transition to '%s' in %d loops\n", clk_name, (state) ? "locked" : "bypassed", i); ret = 0; } return ret; } /* From 3430 TRM ES2 4.7.6.2 */ static u16 _omap3_dpll_compute_freqsel(struct clk_hw_omap *clk, u8 n) { unsigned long fint; u16 f = 0; fint = __clk_get_rate(clk->dpll_data->clk_ref) / n; pr_debug("clock: fint is %lu\n", fint); if (fint >= 750000 && fint <= 1000000) f = 0x3; else if (fint > 1000000 && fint <= 1250000) f = 0x4; else if (fint > 1250000 && fint <= 1500000) f = 0x5; else if (fint > 1500000 && fint <= 1750000) f = 0x6; else if (fint > 1750000 && fint <= 2100000) f = 0x7; else if (fint > 7500000 && fint <= 10000000) f = 0xB; else if (fint > 10000000 && fint <= 12500000) f = 0xC; else if (fint > 12500000 && fint <= 15000000) f = 0xD; else if (fint > 15000000 && fint <= 17500000) f = 0xE; else if (fint > 17500000 && fint <= 21000000) f = 0xF; else pr_debug("clock: unknown freqsel setting for %d\n", n); return f; } /* * _omap3_noncore_dpll_lock - instruct a DPLL to lock and wait for readiness * @clk: pointer to a DPLL struct clk * * Instructs a non-CORE DPLL to lock. Waits for the DPLL to report * readiness before returning. Will save and restore the DPLL's * autoidle state across the enable, per the CDP code. If the DPLL * locked successfully, return 0; if the DPLL did not lock in the time * allotted, or DPLL3 was passed in, return -EINVAL. */ static int _omap3_noncore_dpll_lock(struct clk_hw_omap *clk) { const struct dpll_data *dd; u8 ai; u8 state = 1; int r = 0; pr_debug("clock: locking DPLL %s\n", __clk_get_name(clk->hw.clk)); dd = clk->dpll_data; state <<= __ffs(dd->idlest_mask); /* Check if already locked */ if ((__raw_readl(dd->idlest_reg) & dd->idlest_mask) == state) goto done; ai = omap3_dpll_autoidle_read(clk); if (ai) omap3_dpll_deny_idle(clk); _omap3_dpll_write_clken(clk, DPLL_LOCKED); r = _omap3_wait_dpll_status(clk, 1); if (ai) omap3_dpll_allow_idle(clk); done: return r; } /* * _omap3_noncore_dpll_bypass - instruct a DPLL to bypass and wait for readiness * @clk: pointer to a DPLL struct clk * * Instructs a non-CORE DPLL to enter low-power bypass mode. In * bypass mode, the DPLL's rate is set equal to its parent clock's * rate. Waits for the DPLL to report readiness before returning. * Will save and restore the DPLL's autoidle state across the enable, * per the CDP code. If the DPLL entered bypass mode successfully, * return 0; if the DPLL did not enter bypass in the time allotted, or * DPLL3 was passed in, or the DPLL does not support low-power bypass, * return -EINVAL. */ static int _omap3_noncore_dpll_bypass(struct clk_hw_omap *clk) { int r; u8 ai; if (!(clk->dpll_data->modes & (1 << DPLL_LOW_POWER_BYPASS))) return -EINVAL; pr_debug("clock: configuring DPLL %s for low-power bypass\n", __clk_get_name(clk->hw.clk)); ai = omap3_dpll_autoidle_read(clk); _omap3_dpll_write_clken(clk, DPLL_LOW_POWER_BYPASS); r = _omap3_wait_dpll_status(clk, 0); if (ai) omap3_dpll_allow_idle(clk); return r; } /* * _omap3_noncore_dpll_stop - instruct a DPLL to stop * @clk: pointer to a DPLL struct clk * * Instructs a non-CORE DPLL to enter low-power stop. Will save and * restore the DPLL's autoidle state across the stop, per the CDP * code. If DPLL3 was passed in, or the DPLL does not support * low-power stop, return -EINVAL; otherwise, return 0. */ static int _omap3_noncore_dpll_stop(struct clk_hw_omap *clk) { u8 ai; if (!(clk->dpll_data->modes & (1 << DPLL_LOW_POWER_STOP))) return -EINVAL; pr_debug("clock: stopping DPLL %s\n", __clk_get_name(clk->hw.clk)); ai = omap3_dpll_autoidle_read(clk); _omap3_dpll_write_clken(clk, DPLL_LOW_POWER_STOP); if (ai) omap3_dpll_allow_idle(clk); return 0; } /** * _lookup_dco - Lookup DCO used by j-type DPLL * @clk: pointer to a DPLL struct clk * @dco: digital control oscillator selector * @m: DPLL multiplier to set * @n: DPLL divider to set * * See 36xx TRM section 3.5.3.3.3.2 "Type B DPLL (Low-Jitter)" * * XXX This code is not needed for 3430/AM35xx; can it be optimized * out in non-multi-OMAP builds for those chips? */ static void _lookup_dco(struct clk_hw_omap *clk, u8 *dco, u16 m, u8 n) { unsigned long fint, clkinp; /* watch out for overflow */ clkinp = __clk_get_rate(__clk_get_parent(clk->hw.clk)); fint = (clkinp / n) * m; if (fint < 1000000000) *dco = 2; else *dco = 4; } /** * _lookup_sddiv - Calculate sigma delta divider for j-type DPLL * @clk: pointer to a DPLL struct clk * @sd_div: target sigma-delta divider * @m: DPLL multiplier to set * @n: DPLL divider to set * * See 36xx TRM section 3.5.3.3.3.2 "Type B DPLL (Low-Jitter)" * * XXX This code is not needed for 3430/AM35xx; can it be optimized * out in non-multi-OMAP builds for those chips? */ static void _lookup_sddiv(struct clk_hw_omap *clk, u8 *sd_div, u16 m, u8 n) { unsigned long clkinp, sd; /* watch out for overflow */ int mod1, mod2; clkinp = __clk_get_rate(__clk_get_parent(clk->hw.clk)); /* * target sigma-delta to near 250MHz * sd = ceil[(m/(n+1)) * (clkinp_MHz / 250)] */ clkinp /= 100000; /* shift from MHz to 10*Hz for 38.4 and 19.2 */ mod1 = (clkinp * m) % (250 * n); sd = (clkinp * m) / (250 * n); mod2 = sd % 10; sd /= 10; if (mod1 || mod2) sd++; *sd_div = sd; } /* * _omap3_noncore_dpll_program - set non-core DPLL M,N values directly * @clk: struct clk * of DPLL to set * @m: DPLL multiplier to set * @n: DPLL divider to set * @freqsel: FREQSEL value to set * * Program the DPLL with the supplied M, N values, and wait for the DPLL to * lock.. Returns -EINVAL upon error, or 0 upon success. */ static int omap3_noncore_dpll_program(struct clk_hw_omap *clk, u16 m, u8 n, u16 freqsel) { struct dpll_data *dd = clk->dpll_data; u8 dco, sd_div; u32 v; /* 3430 ES2 TRM: 4.7.6.9 DPLL Programming Sequence */ _omap3_noncore_dpll_bypass(clk); /* * Set jitter correction. No jitter correction for OMAP4 and 3630 * since freqsel field is no longer present */ if (!soc_is_am33xx() && !cpu_is_omap44xx() && !cpu_is_omap3630()) { v = __raw_readl(dd->control_reg); v &= ~dd->freqsel_mask; v |= freqsel << __ffs(dd->freqsel_mask); __raw_writel(v, dd->control_reg); } /* Set DPLL multiplier, divider */ v = __raw_readl(dd->mult_div1_reg); v &= ~(dd->mult_mask | dd->div1_mask); v |= m << __ffs(dd->mult_mask); v |= (n - 1) << __ffs(dd->div1_mask); /* Configure dco and sd_div for dplls that have these fields */ if (dd->dco_mask) { _lookup_dco(clk, &dco, m, n); v &= ~(dd->dco_mask); v |= dco << __ffs(dd->dco_mask); } if (dd->sddiv_mask) { _lookup_sddiv(clk, &sd_div, m, n); v &= ~(dd->sddiv_mask); v |= sd_div << __ffs(dd->sddiv_mask); } __raw_writel(v, dd->mult_div1_reg); /* We let the clock framework set the other output dividers later */ /* REVISIT: Set ramp-up delay? */ _omap3_noncore_dpll_lock(clk); return 0; } /* Public functions */ /** * omap3_dpll_recalc - recalculate DPLL rate * @clk: DPLL struct clk * * Recalculate and propagate the DPLL rate. */ unsigned long omap3_dpll_recalc(struct clk_hw *hw, unsigned long parent_rate) { struct clk_hw_omap *clk = to_clk_hw_omap(hw); return omap2_get_dpll_rate(clk); } /* Non-CORE DPLL (e.g., DPLLs that do not control SDRC) clock functions */ /** * omap3_noncore_dpll_enable - instruct a DPLL to enter bypass or lock mode * @clk: pointer to a DPLL struct clk * * Instructs a non-CORE DPLL to enable, e.g., to enter bypass or lock. * The choice of modes depends on the DPLL's programmed rate: if it is * the same as the DPLL's parent clock, it will enter bypass; * otherwise, it will enter lock. This code will wait for the DPLL to * indicate readiness before returning, unless the DPLL takes too long * to enter the target state. Intended to be used as the struct clk's * enable function. If DPLL3 was passed in, or the DPLL does not * support low-power stop, or if the DPLL took too long to enter * bypass or lock, return -EINVAL; otherwise, return 0. */ int omap3_noncore_dpll_enable(struct clk_hw *hw) { struct clk_hw_omap *clk = to_clk_hw_omap(hw); int r; struct dpll_data *dd; struct clk *parent; dd = clk->dpll_data; if (!dd) return -EINVAL; if (clk->clkdm) { r = clkdm_clk_enable(clk->clkdm, hw->clk); if (r) { WARN(1, "%s: could not enable %s's clockdomain %s: %d\n", __func__, __clk_get_name(hw->clk), clk->clkdm->name, r); return r; } } parent = __clk_get_parent(hw->clk); if (__clk_get_rate(hw->clk) == __clk_get_rate(dd->clk_bypass)) { WARN_ON(parent != dd->clk_bypass); r = _omap3_noncore_dpll_bypass(clk); } else { WARN_ON(parent != dd->clk_ref); r = _omap3_noncore_dpll_lock(clk); } return r; } /** * omap3_noncore_dpll_disable - instruct a DPLL to enter low-power stop * @clk: pointer to a DPLL struct clk * * Instructs a non-CORE DPLL to enter low-power stop. This function is * intended for use in struct clkops. No return value. */ void omap3_noncore_dpll_disable(struct clk_hw *hw) { struct clk_hw_omap *clk = to_clk_hw_omap(hw); _omap3_noncore_dpll_stop(clk); if (clk->clkdm) clkdm_clk_disable(clk->clkdm, hw->clk); } /* Non-CORE DPLL rate set code */ /** * omap3_noncore_dpll_set_rate - set non-core DPLL rate * @clk: struct clk * of DPLL to set * @rate: rounded target rate * * Set the DPLL CLKOUT to the target rate. If the DPLL can enter * low-power bypass, and the target rate is the bypass source clock * rate, then configure the DPLL for bypass. Otherwise, round the * target rate if it hasn't been done already, then program and lock * the DPLL. Returns -EINVAL upon error, or 0 upon success. */ int omap3_noncore_dpll_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long parent_rate) { struct clk_hw_omap *clk = to_clk_hw_omap(hw); struct clk *new_parent = NULL; u16 freqsel = 0; struct dpll_data *dd; int ret; if (!hw || !rate) return -EINVAL; dd = clk->dpll_data; if (!dd) return -EINVAL; __clk_prepare(dd->clk_bypass); clk_enable(dd->clk_bypass); __clk_prepare(dd->clk_ref); clk_enable(dd->clk_ref); if (__clk_get_rate(dd->clk_bypass) == rate && (dd->modes & (1 << DPLL_LOW_POWER_BYPASS))) { pr_debug("%s: %s: set rate: entering bypass.\n", __func__, __clk_get_name(hw->clk)); ret = _omap3_noncore_dpll_bypass(clk); if (!ret) new_parent = dd->clk_bypass; } else { if (dd->last_rounded_rate != rate) rate = __clk_round_rate(hw->clk, rate); if (dd->last_rounded_rate == 0) return -EINVAL; /* No freqsel on OMAP4 and OMAP3630 */ if (!cpu_is_omap44xx() && !cpu_is_omap3630()) { freqsel = _omap3_dpll_compute_freqsel(clk, dd->last_rounded_n); if (!freqsel) WARN_ON(1); } pr_debug("%s: %s: set rate: locking rate to %lu.\n", __func__, __clk_get_name(hw->clk), rate); ret = omap3_noncore_dpll_program(clk, dd->last_rounded_m, dd->last_rounded_n, freqsel); if (!ret) new_parent = dd->clk_ref; } /* * FIXME - this is all wrong. common code handles reparenting and * migrating prepare/enable counts. dplls should be a multiplexer * clock and this should be a set_parent operation so that all of that * stuff is inherited for free */ if (!ret) __clk_reparent(hw->clk, new_parent); clk_disable(dd->clk_ref); __clk_unprepare(dd->clk_ref); clk_disable(dd->clk_bypass); __clk_unprepare(dd->clk_bypass); return 0; } /* DPLL autoidle read/set code */ /** * omap3_dpll_autoidle_read - read a DPLL's autoidle bits * @clk: struct clk * of the DPLL to read * * Return the DPLL's autoidle bits, shifted down to bit 0. Returns * -EINVAL if passed a null pointer or if the struct clk does not * appear to refer to a DPLL. */ u32 omap3_dpll_autoidle_read(struct clk_hw_omap *clk) { const struct dpll_data *dd; u32 v; if (!clk || !clk->dpll_data) return -EINVAL; dd = clk->dpll_data; if (!dd->autoidle_reg) return -EINVAL; v = __raw_readl(dd->autoidle_reg); v &= dd->autoidle_mask; v >>= __ffs(dd->autoidle_mask); return v; } /** * omap3_dpll_allow_idle - enable DPLL autoidle bits * @clk: struct clk * of the DPLL to operate on * * Enable DPLL automatic idle control. This automatic idle mode * switching takes effect only when the DPLL is locked, at least on * OMAP3430. The DPLL will enter low-power stop when its downstream * clocks are gated. No return value. */ void omap3_dpll_allow_idle(struct clk_hw_omap *clk) { const struct dpll_data *dd; u32 v; if (!clk || !clk->dpll_data) return; dd = clk->dpll_data; if (!dd->autoidle_reg) return; /* * REVISIT: CORE DPLL can optionally enter low-power bypass * by writing 0x5 instead of 0x1. Add some mechanism to * optionally enter this mode. */ v = __raw_readl(dd->autoidle_reg); v &= ~dd->autoidle_mask; v |= DPLL_AUTOIDLE_LOW_POWER_STOP << __ffs(dd->autoidle_mask); __raw_writel(v, dd->autoidle_reg); } /** * omap3_dpll_deny_idle - prevent DPLL from automatically idling * @clk: struct clk * of the DPLL to operate on * * Disable DPLL automatic idle control. No return value. */ void omap3_dpll_deny_idle(struct clk_hw_omap *clk) { const struct dpll_data *dd; u32 v; if (!clk || !clk->dpll_data) return; dd = clk->dpll_data; if (!dd->autoidle_reg) return; v = __raw_readl(dd->autoidle_reg); v &= ~dd->autoidle_mask; v |= DPLL_AUTOIDLE_DISABLE << __ffs(dd->autoidle_mask); __raw_writel(v, dd->autoidle_reg); } /* Clock control for DPLL outputs */ /** * omap3_clkoutx2_recalc - recalculate DPLL X2 output virtual clock rate * @clk: DPLL output struct clk * * Using parent clock DPLL data, look up DPLL state. If locked, set our * rate to the dpll_clk * 2; otherwise, just use dpll_clk. */ unsigned long omap3_clkoutx2_recalc(struct clk_hw *hw, unsigned long parent_rate) { const struct dpll_data *dd; unsigned long rate; u32 v; struct clk_hw_omap *pclk = NULL; struct clk *parent; /* Walk up the parents of clk, looking for a DPLL */ do { do { parent = __clk_get_parent(hw->clk); hw = __clk_get_hw(parent); } while (hw && (__clk_get_flags(hw->clk) & CLK_IS_BASIC)); if (!hw) break; pclk = to_clk_hw_omap(hw); } while (pclk && !pclk->dpll_data); /* clk does not have a DPLL as a parent? error in the clock data */ if (!pclk) { WARN_ON(1); return 0; } dd = pclk->dpll_data; WARN_ON(!dd->enable_mask); v = __raw_readl(dd->control_reg) & dd->enable_mask; v >>= __ffs(dd->enable_mask); if ((v != OMAP3XXX_EN_DPLL_LOCKED) || (dd->flags & DPLL_J_TYPE)) rate = parent_rate; else rate = parent_rate * 2; return rate; } /* OMAP3/4 non-CORE DPLL clkops */ const struct clk_hw_omap_ops clkhwops_omap3_dpll = { .allow_idle = omap3_dpll_allow_idle, .deny_idle = omap3_dpll_deny_idle, };