From bda003036684b9779fca2b3d457621eaff9bcd0a Mon Sep 17 00:00:00 2001 From: Robert Jarzmik Date: Wed, 30 Jul 2014 22:50:59 +0200 Subject: clk: add pxa clocks infrastructure Add a the common code used by all PXA variants. This is the first step in the transition from architecture defined clocks (in arch/arm/mach-pxa) towards clock framework. The goal is to have the same features (and not all the features) of the existing clocks, and enable the transition of PXA to device-tree. All PXA rely on a "CKEN" type clock, which : - has a gate (bit in CKEN register) - is generated from a PLL, generally divided - has an alternate low power clock Each variant will specialize the CKEN clock : - pxa25x have no low power clock - pxa27x in low power use always the 13 MHz ring oscillator - pxa3xx in low power have specific dividers for each clock The device-tree provides a list of CLK_* (ex: CLK_USB or CLK_I2C) to get a handle on the clock. While pxa-clock.h will describe all the clocks of all the variants, each variant will only use a subset of it. Signed-off-by: Robert Jarzmik Signed-off-by: Mike Turquette --- drivers/clk/pxa/clk-pxa.c | 97 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 97 insertions(+) create mode 100644 drivers/clk/pxa/clk-pxa.c (limited to 'drivers/clk/pxa/clk-pxa.c') diff --git a/drivers/clk/pxa/clk-pxa.c b/drivers/clk/pxa/clk-pxa.c new file mode 100644 index 000000000000..ef3c05389c0a --- /dev/null +++ b/drivers/clk/pxa/clk-pxa.c @@ -0,0 +1,97 @@ +/* + * Marvell PXA family clocks + * + * Copyright (C) 2014 Robert Jarzmik + * + * Common clock code for PXA clocks ("CKEN" type clocks + DT) + * + * 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; version 2 of the License. + * + */ +#include +#include +#include +#include + +#include +#include "clk-pxa.h" + +DEFINE_SPINLOCK(lock); + +static struct clk *pxa_clocks[CLK_MAX]; +static struct clk_onecell_data onecell_data = { + .clks = pxa_clocks, + .clk_num = CLK_MAX, +}; + +#define to_pxa_clk(_hw) container_of(_hw, struct pxa_clk_cken, hw) + +static unsigned long cken_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct pxa_clk_cken *pclk = to_pxa_clk(hw); + struct clk_fixed_factor *fix; + + if (!pclk->is_in_low_power || pclk->is_in_low_power()) + fix = &pclk->lp; + else + fix = &pclk->hp; + fix->hw.clk = hw->clk; + return clk_fixed_factor_ops.recalc_rate(&fix->hw, parent_rate); +} + +static struct clk_ops cken_rate_ops = { + .recalc_rate = cken_recalc_rate, +}; + +static u8 cken_get_parent(struct clk_hw *hw) +{ + struct pxa_clk_cken *pclk = to_pxa_clk(hw); + + if (!pclk->is_in_low_power) + return 0; + return pclk->is_in_low_power() ? 0 : 1; +} + +static struct clk_ops cken_mux_ops = { + .get_parent = cken_get_parent, + .set_parent = dummy_clk_set_parent, +}; + +void __init clkdev_pxa_register(int ckid, const char *con_id, + const char *dev_id, struct clk *clk) +{ + if (!IS_ERR(clk) && (ckid != CLK_NONE)) + pxa_clocks[ckid] = clk; + if (!IS_ERR(clk)) + clk_register_clkdev(clk, con_id, dev_id); +} + +int __init clk_pxa_cken_init(struct pxa_clk_cken *clks, int nb_clks) +{ + int i; + struct pxa_clk_cken *pclk; + struct clk *clk; + + for (i = 0; i < nb_clks; i++) { + pclk = clks + i; + pclk->gate.lock = &lock; + clk = clk_register_composite(NULL, pclk->name, + pclk->parent_names, 2, + &pclk->hw, &cken_mux_ops, + &pclk->hw, &cken_rate_ops, + &pclk->gate.hw, &clk_gate_ops, + pclk->flags); + clkdev_pxa_register(pclk->ckid, pclk->con_id, pclk->dev_id, + clk); + } + return 0; +} + +static void __init pxa_dt_clocks_init(struct device_node *np) +{ + of_clk_add_provider(np, of_clk_src_onecell_get, &onecell_data); +} +CLK_OF_DECLARE(pxa_clks, "marvell,pxa-clocks", pxa_dt_clocks_init); -- cgit v1.2.3