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- /*
- * 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-provider.h>
- #include <linux/io.h>
- #include <asm/div64.h>
- #include "soc.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_hw_omap *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_get_rate(__clk_get_parent(clk->hw.clk)) / 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;
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