diff options
Diffstat (limited to 'arch/arm/mach-omap2/clock3xxx.c')
| -rw-r--r-- | arch/arm/mach-omap2/clock3xxx.c | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/clock3xxx.c b/arch/arm/mach-omap2/clock3xxx.c new file mode 100644 index 000000000..a9e86db5d --- /dev/null +++ b/arch/arm/mach-omap2/clock3xxx.c @@ -0,0 +1,135 @@ +/* + * OMAP3-specific clock framework functions + * + * Copyright (C) 2007-2008 Texas Instruments, Inc. + * Copyright (C) 2007-2010 Nokia Corporation + * + * Paul Walmsley + * Jouni Högander + * + * 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. + */ +#undef DEBUG + +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/clk.h> +#include <linux/io.h> + +#include "soc.h" +#include "clock.h" +#include "clock3xxx.h" +#include "prm2xxx_3xxx.h" +#include "prm-regbits-34xx.h" +#include "cm2xxx_3xxx.h" +#include "cm-regbits-34xx.h" + +/* + * DPLL5_FREQ_FOR_USBHOST: USBHOST and USBTLL are the only clocks + * that are sourced by DPLL5, and both of these require this clock + * to be at 120 MHz for proper operation. + */ +#define DPLL5_FREQ_FOR_USBHOST 120000000 + +/* needed by omap3_core_dpll_m2_set_rate() */ +struct clk *sdrc_ick_p, *arm_fck_p; + +/** + * omap3_dpll4_set_rate - set rate for omap3 per-dpll + * @hw: clock to change + * @rate: target rate for clock + * @parent_rate: rate of the parent clock + * + * Check if the current SoC supports the per-dpll reprogram operation + * or not, and then do the rate change if supported. Returns -EINVAL + * if not supported, 0 for success, and potential error codes from the + * clock rate change. + */ +int omap3_dpll4_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + /* + * According to the 12-5 CDP code from TI, "Limitation 2.5" + * on 3430ES1 prevents us from changing DPLL multipliers or dividers + * on DPLL4. + */ + if (ti_clk_features.flags & TI_CLK_DPLL4_DENY_REPROGRAM) { + pr_err("clock: DPLL4 cannot change rate due to silicon 'Limitation 2.5' on 3430ES1.\n"); + return -EINVAL; + } + + return omap3_noncore_dpll_set_rate(hw, rate, parent_rate); +} + +/** + * omap3_dpll4_set_rate_and_parent - set rate and parent for omap3 per-dpll + * @hw: clock to change + * @rate: target rate for clock + * @parent_rate: rate of the parent clock + * @index: parent index, 0 - reference clock, 1 - bypass clock + * + * Check if the current SoC support the per-dpll reprogram operation + * or not, and then do the rate + parent change if supported. Returns + * -EINVAL if not supported, 0 for success, and potential error codes + * from the clock rate change. + */ +int omap3_dpll4_set_rate_and_parent(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate, u8 index) +{ + if (ti_clk_features.flags & TI_CLK_DPLL4_DENY_REPROGRAM) { + pr_err("clock: DPLL4 cannot change rate due to silicon 'Limitation 2.5' on 3430ES1.\n"); + return -EINVAL; + } + + return omap3_noncore_dpll_set_rate_and_parent(hw, rate, parent_rate, + index); +} + +void __init omap3_clk_lock_dpll5(void) +{ + struct clk *dpll5_clk; + struct clk *dpll5_m2_clk; + + dpll5_clk = clk_get(NULL, "dpll5_ck"); + clk_set_rate(dpll5_clk, DPLL5_FREQ_FOR_USBHOST); + clk_prepare_enable(dpll5_clk); + + /* Program dpll5_m2_clk divider for no division */ + dpll5_m2_clk = clk_get(NULL, "dpll5_m2_ck"); + clk_prepare_enable(dpll5_m2_clk); + clk_set_rate(dpll5_m2_clk, DPLL5_FREQ_FOR_USBHOST); + + clk_disable_unprepare(dpll5_m2_clk); + clk_disable_unprepare(dpll5_clk); + return; +} + +/* Common clock code */ + +/* + * Switch the MPU rate if specified on cmdline. We cannot do this + * early until cmdline is parsed. XXX This should be removed from the + * clock code and handled by the OPP layer code in the near future. + */ +static int __init omap3xxx_clk_arch_init(void) +{ + int ret; + + if (!cpu_is_omap34xx()) + return 0; + + ret = omap2_clk_switch_mpurate_at_boot("dpll1_ck"); + if (!ret) + omap2_clk_print_new_rates("osc_sys_ck", "core_ck", "arm_fck"); + + return ret; +} + +omap_arch_initcall(omap3xxx_clk_arch_init); + + |