diff options
Diffstat (limited to 'ANDROID_3.4.5/arch/arm/mach-omap2/clkt_dpll.c')
| -rw-r--r-- | ANDROID_3.4.5/arch/arm/mach-omap2/clkt_dpll.c | 360 |
1 files changed, 0 insertions, 360 deletions
diff --git a/ANDROID_3.4.5/arch/arm/mach-omap2/clkt_dpll.c b/ANDROID_3.4.5/arch/arm/mach-omap2/clkt_dpll.c deleted file mode 100644 index cd7fd0f9..00000000 --- a/ANDROID_3.4.5/arch/arm/mach-omap2/clkt_dpll.c +++ /dev/null @@ -1,360 +0,0 @@ -/* - * OMAP2/3/4 DPLL clock functions - * - * Copyright (C) 2005-2008 Texas Instruments, Inc. - * Copyright (C) 2004-2010 Nokia Corporation - * - * Contacts: - * Richard Woodruff <r-woodruff2@ti.com> - * Paul Walmsley - * - * 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. - */ -#undef DEBUG - -#include <linux/kernel.h> -#include <linux/errno.h> -#include <linux/clk.h> -#include <linux/io.h> - -#include <asm/div64.h> - -#include <plat/clock.h> -#include <plat/cpu.h> - -#include "clock.h" -#include "cm-regbits-24xx.h" -#include "cm-regbits-34xx.h" - -/* DPLL rate rounding: minimum DPLL multiplier, divider values */ -#define DPLL_MIN_MULTIPLIER 2 -#define DPLL_MIN_DIVIDER 1 - -/* Possible error results from _dpll_test_mult */ -#define DPLL_MULT_UNDERFLOW -1 - -/* - * Scale factor to mitigate roundoff errors in DPLL rate rounding. - * The higher the scale factor, the greater the risk of arithmetic overflow, - * but the closer the rounded rate to the target rate. DPLL_SCALE_FACTOR - * must be a power of DPLL_SCALE_BASE. - */ -#define DPLL_SCALE_FACTOR 64 -#define DPLL_SCALE_BASE 2 -#define DPLL_ROUNDING_VAL ((DPLL_SCALE_BASE / 2) * \ - (DPLL_SCALE_FACTOR / DPLL_SCALE_BASE)) - -/* DPLL valid Fint frequency band limits - from 34xx TRM Section 4.7.6.2 */ -#define OMAP3430_DPLL_FINT_BAND1_MIN 750000 -#define OMAP3430_DPLL_FINT_BAND1_MAX 2100000 -#define OMAP3430_DPLL_FINT_BAND2_MIN 7500000 -#define OMAP3430_DPLL_FINT_BAND2_MAX 21000000 - -/* - * DPLL valid Fint frequency range for OMAP36xx and OMAP4xxx. - * From device data manual section 4.3 "DPLL and DLL Specifications". - */ -#define OMAP3PLUS_DPLL_FINT_JTYPE_MIN 500000 -#define OMAP3PLUS_DPLL_FINT_JTYPE_MAX 2500000 -#define OMAP3PLUS_DPLL_FINT_MIN 32000 -#define OMAP3PLUS_DPLL_FINT_MAX 52000000 - -/* _dpll_test_fint() return codes */ -#define DPLL_FINT_UNDERFLOW -1 -#define DPLL_FINT_INVALID -2 - -/* Private functions */ - -/* - * _dpll_test_fint - test whether an Fint value is valid for the DPLL - * @clk: DPLL struct clk to test - * @n: divider value (N) to test - * - * Tests whether a particular divider @n will result in a valid DPLL - * internal clock frequency Fint. See the 34xx TRM 4.7.6.2 "DPLL Jitter - * Correction". Returns 0 if OK, -1 if the enclosing loop can terminate - * (assuming that it is counting N upwards), or -2 if the enclosing loop - * should skip to the next iteration (again assuming N is increasing). - */ -static int _dpll_test_fint(struct clk *clk, u8 n) -{ - struct dpll_data *dd; - long fint, fint_min, fint_max; - int ret = 0; - - dd = clk->dpll_data; - - /* DPLL divider must result in a valid jitter correction val */ - fint = clk->parent->rate / n; - - if (cpu_is_omap24xx()) { - /* Should not be called for OMAP2, so warn if it is called */ - WARN(1, "No fint limits available for OMAP2!\n"); - return DPLL_FINT_INVALID; - } else if (cpu_is_omap3430()) { - fint_min = OMAP3430_DPLL_FINT_BAND1_MIN; - fint_max = OMAP3430_DPLL_FINT_BAND2_MAX; - } else if (dd->flags & DPLL_J_TYPE) { - fint_min = OMAP3PLUS_DPLL_FINT_JTYPE_MIN; - fint_max = OMAP3PLUS_DPLL_FINT_JTYPE_MAX; - } else { - fint_min = OMAP3PLUS_DPLL_FINT_MIN; - fint_max = OMAP3PLUS_DPLL_FINT_MAX; - } - - if (fint < fint_min) { - pr_debug("rejecting n=%d due to Fint failure, " - "lowering max_divider\n", n); - dd->max_divider = n; - ret = DPLL_FINT_UNDERFLOW; - } else if (fint > fint_max) { - pr_debug("rejecting n=%d due to Fint failure, " - "boosting min_divider\n", n); - dd->min_divider = n; - ret = DPLL_FINT_INVALID; - } else if (cpu_is_omap3430() && fint > OMAP3430_DPLL_FINT_BAND1_MAX && - fint < OMAP3430_DPLL_FINT_BAND2_MIN) { - pr_debug("rejecting n=%d due to Fint failure\n", n); - ret = DPLL_FINT_INVALID; - } - - return ret; -} - -static unsigned long _dpll_compute_new_rate(unsigned long parent_rate, - unsigned int m, unsigned int n) -{ - unsigned long long num; - - num = (unsigned long long)parent_rate * m; - do_div(num, n); - return num; -} - -/* - * _dpll_test_mult - test a DPLL multiplier value - * @m: pointer to the DPLL m (multiplier) value under test - * @n: current DPLL n (divider) value under test - * @new_rate: pointer to storage for the resulting rounded rate - * @target_rate: the desired DPLL rate - * @parent_rate: the DPLL's parent clock rate - * - * This code tests a DPLL multiplier value, ensuring that the - * resulting rate will not be higher than the target_rate, and that - * the multiplier value itself is valid for the DPLL. Initially, the - * integer pointed to by the m argument should be prescaled by - * multiplying by DPLL_SCALE_FACTOR. The code will replace this with - * a non-scaled m upon return. This non-scaled m will result in a - * new_rate as close as possible to target_rate (but not greater than - * target_rate) given the current (parent_rate, n, prescaled m) - * triple. Returns DPLL_MULT_UNDERFLOW in the event that the - * non-scaled m attempted to underflow, which can allow the calling - * function to bail out early; or 0 upon success. - */ -static int _dpll_test_mult(int *m, int n, unsigned long *new_rate, - unsigned long target_rate, - unsigned long parent_rate) -{ - int r = 0, carry = 0; - - /* Unscale m and round if necessary */ - if (*m % DPLL_SCALE_FACTOR >= DPLL_ROUNDING_VAL) - carry = 1; - *m = (*m / DPLL_SCALE_FACTOR) + carry; - - /* - * The new rate must be <= the target rate to avoid programming - * a rate that is impossible for the hardware to handle - */ - *new_rate = _dpll_compute_new_rate(parent_rate, *m, n); - if (*new_rate > target_rate) { - (*m)--; - *new_rate = 0; - } - - /* Guard against m underflow */ - if (*m < DPLL_MIN_MULTIPLIER) { - *m = DPLL_MIN_MULTIPLIER; - *new_rate = 0; - r = DPLL_MULT_UNDERFLOW; - } - - if (*new_rate == 0) - *new_rate = _dpll_compute_new_rate(parent_rate, *m, n); - - return r; -} - -/* Public functions */ - -void omap2_init_dpll_parent(struct clk *clk) -{ - u32 v; - struct dpll_data *dd; - - dd = clk->dpll_data; - if (!dd) - return; - - v = __raw_readl(dd->control_reg); - v &= dd->enable_mask; - v >>= __ffs(dd->enable_mask); - - /* Reparent the struct clk in case the dpll is in bypass */ - if (cpu_is_omap24xx()) { - if (v == OMAP2XXX_EN_DPLL_LPBYPASS || - v == OMAP2XXX_EN_DPLL_FRBYPASS) - clk_reparent(clk, dd->clk_bypass); - } else if (cpu_is_omap34xx()) { - if (v == OMAP3XXX_EN_DPLL_LPBYPASS || - v == OMAP3XXX_EN_DPLL_FRBYPASS) - clk_reparent(clk, dd->clk_bypass); - } else if (cpu_is_omap44xx()) { - if (v == OMAP4XXX_EN_DPLL_LPBYPASS || - v == OMAP4XXX_EN_DPLL_FRBYPASS || - v == OMAP4XXX_EN_DPLL_MNBYPASS) - clk_reparent(clk, dd->clk_bypass); - } - return; -} - -/** - * omap2_get_dpll_rate - returns the current DPLL CLKOUT rate - * @clk: struct clk * of a DPLL - * - * DPLLs can be locked or bypassed - basically, enabled or disabled. - * When locked, the DPLL output depends on the M and N values. When - * bypassed, on OMAP2xxx, the output rate is either the 32KiHz clock - * or sys_clk. Bypass rates on OMAP3 depend on the DPLL: DPLLs 1 and - * 2 are bypassed with dpll1_fclk and dpll2_fclk respectively - * (generated by DPLL3), while DPLL 3, 4, and 5 bypass rates are sys_clk. - * Returns the current DPLL CLKOUT rate (*not* CLKOUTX2) if the DPLL is - * locked, or the appropriate bypass rate if the DPLL is bypassed, or 0 - * if the clock @clk is not a DPLL. - */ -u32 omap2_get_dpll_rate(struct clk *clk) -{ - long long dpll_clk; - u32 dpll_mult, dpll_div, v; - struct dpll_data *dd; - - dd = clk->dpll_data; - if (!dd) - return 0; - - /* Return bypass rate if DPLL is bypassed */ - v = __raw_readl(dd->control_reg); - v &= dd->enable_mask; - v >>= __ffs(dd->enable_mask); - - if (cpu_is_omap24xx()) { - if (v == OMAP2XXX_EN_DPLL_LPBYPASS || - v == OMAP2XXX_EN_DPLL_FRBYPASS) - return dd->clk_bypass->rate; - } else if (cpu_is_omap34xx()) { - if (v == OMAP3XXX_EN_DPLL_LPBYPASS || - v == OMAP3XXX_EN_DPLL_FRBYPASS) - return dd->clk_bypass->rate; - } else if (cpu_is_omap44xx()) { - if (v == OMAP4XXX_EN_DPLL_LPBYPASS || - v == OMAP4XXX_EN_DPLL_FRBYPASS || - v == OMAP4XXX_EN_DPLL_MNBYPASS) - return dd->clk_bypass->rate; - } - - v = __raw_readl(dd->mult_div1_reg); - dpll_mult = v & dd->mult_mask; - dpll_mult >>= __ffs(dd->mult_mask); - dpll_div = v & dd->div1_mask; - dpll_div >>= __ffs(dd->div1_mask); - - dpll_clk = (long long)dd->clk_ref->rate * dpll_mult; - do_div(dpll_clk, dpll_div + 1); - - return dpll_clk; -} - -/* DPLL rate rounding code */ - -/** - * omap2_dpll_round_rate - round a target rate for an OMAP DPLL - * @clk: struct clk * for a DPLL - * @target_rate: desired DPLL clock rate - * - * Given a DPLL and a desired target rate, round the target rate to a - * possible, programmable rate for this DPLL. Attempts to select the - * minimum possible n. Stores the computed (m, n) in the DPLL's - * dpll_data structure so set_rate() will not need to call this - * (expensive) function again. Returns ~0 if the target rate cannot - * be rounded, or the rounded rate upon success. - */ -long omap2_dpll_round_rate(struct clk *clk, unsigned long target_rate) -{ - int m, n, r, scaled_max_m; - unsigned long scaled_rt_rp; - unsigned long new_rate = 0; - struct dpll_data *dd; - - if (!clk || !clk->dpll_data) - return ~0; - - dd = clk->dpll_data; - - pr_debug("clock: %s: starting DPLL round_rate, target rate %ld\n", - clk->name, target_rate); - - scaled_rt_rp = target_rate / (dd->clk_ref->rate / DPLL_SCALE_FACTOR); - scaled_max_m = dd->max_multiplier * DPLL_SCALE_FACTOR; - - dd->last_rounded_rate = 0; - - for (n = dd->min_divider; n <= dd->max_divider; n++) { - - /* Is the (input clk, divider) pair valid for the DPLL? */ - r = _dpll_test_fint(clk, n); - if (r == DPLL_FINT_UNDERFLOW) - break; - else if (r == DPLL_FINT_INVALID) - continue; - - /* Compute the scaled DPLL multiplier, based on the divider */ - m = scaled_rt_rp * n; - - /* - * Since we're counting n up, a m overflow means we - * can bail out completely (since as n increases in - * the next iteration, there's no way that m can - * increase beyond the current m) - */ - if (m > scaled_max_m) - break; - - r = _dpll_test_mult(&m, n, &new_rate, target_rate, - dd->clk_ref->rate); - - /* m can't be set low enough for this n - try with a larger n */ - if (r == DPLL_MULT_UNDERFLOW) - continue; - - pr_debug("clock: %s: m = %d: n = %d: new_rate = %ld\n", - clk->name, m, n, new_rate); - - if (target_rate == new_rate) { - dd->last_rounded_m = m; - dd->last_rounded_n = n; - dd->last_rounded_rate = target_rate; - break; - } - } - - if (target_rate != new_rate) { - pr_debug("clock: %s: cannot round to rate %ld\n", clk->name, - target_rate); - return ~0; - } - - return target_rate; -} - |