diff options
Diffstat (limited to 'drivers/clk/ux500/clk-prcmu.c')
| -rw-r--r-- | drivers/clk/ux500/clk-prcmu.c | 238 |
1 files changed, 238 insertions, 0 deletions
diff --git a/drivers/clk/ux500/clk-prcmu.c b/drivers/clk/ux500/clk-prcmu.c new file mode 100644 index 000000000000..1d779ad12169 --- /dev/null +++ b/drivers/clk/ux500/clk-prcmu.c @@ -0,0 +1,238 @@ +/* + * PRCMU clock implementation for ux500 platform. + * + * Copyright (C) 2012 ST-Ericsson SA + * Author: Ulf Hansson <ulf.hansson@linaro.org> + * + * License terms: GNU General Public License (GPL) version 2 + */ + +#include <linux/clk-provider.h> +#include <linux/clk-private.h> +#include <linux/mfd/dbx500-prcmu.h> +#include <linux/slab.h> +#include <linux/io.h> +#include <linux/err.h> +#include "clk.h" + +#define to_clk_prcmu(_hw) container_of(_hw, struct clk_prcmu, hw) + +struct clk_prcmu { + struct clk_hw hw; + u8 cg_sel; + int is_enabled; +}; + +/* PRCMU clock operations. */ + +static int clk_prcmu_prepare(struct clk_hw *hw) +{ + struct clk_prcmu *clk = to_clk_prcmu(hw); + return prcmu_request_clock(clk->cg_sel, true); +} + +static void clk_prcmu_unprepare(struct clk_hw *hw) +{ + struct clk_prcmu *clk = to_clk_prcmu(hw); + if (prcmu_request_clock(clk->cg_sel, false)) + pr_err("clk_prcmu: %s failed to disable %s.\n", __func__, + hw->init->name); +} + +static int clk_prcmu_enable(struct clk_hw *hw) +{ + struct clk_prcmu *clk = to_clk_prcmu(hw); + clk->is_enabled = 1; + return 0; +} + +static void clk_prcmu_disable(struct clk_hw *hw) +{ + struct clk_prcmu *clk = to_clk_prcmu(hw); + clk->is_enabled = 0; +} + +static int clk_prcmu_is_enabled(struct clk_hw *hw) +{ + struct clk_prcmu *clk = to_clk_prcmu(hw); + return clk->is_enabled; +} + +static unsigned long clk_prcmu_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clk_prcmu *clk = to_clk_prcmu(hw); + return prcmu_clock_rate(clk->cg_sel); +} + +static long clk_prcmu_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + struct clk_prcmu *clk = to_clk_prcmu(hw); + return prcmu_round_clock_rate(clk->cg_sel, rate); +} + +static int clk_prcmu_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clk_prcmu *clk = to_clk_prcmu(hw); + return prcmu_set_clock_rate(clk->cg_sel, rate); +} + +static int request_ape_opp100(bool enable) +{ + static int reqs; + int err = 0; + + if (enable) { + if (!reqs) + err = prcmu_qos_add_requirement(PRCMU_QOS_APE_OPP, + "clock", 100); + if (!err) + reqs++; + } else { + reqs--; + if (!reqs) + prcmu_qos_remove_requirement(PRCMU_QOS_APE_OPP, + "clock"); + } + return err; +} + +static int clk_prcmu_opp_prepare(struct clk_hw *hw) +{ + int err; + struct clk_prcmu *clk = to_clk_prcmu(hw); + + err = request_ape_opp100(true); + if (err) { + pr_err("clk_prcmu: %s failed to request APE OPP100 for %s.\n", + __func__, hw->init->name); + return err; + } + + err = prcmu_request_clock(clk->cg_sel, true); + if (err) + request_ape_opp100(false); + + return err; +} + +static void clk_prcmu_opp_unprepare(struct clk_hw *hw) +{ + struct clk_prcmu *clk = to_clk_prcmu(hw); + + if (prcmu_request_clock(clk->cg_sel, false)) + goto out_error; + if (request_ape_opp100(false)) + goto out_error; + return; + +out_error: + pr_err("clk_prcmu: %s failed to disable %s.\n", __func__, + hw->init->name); +} + +static struct clk_ops clk_prcmu_scalable_ops = { + .prepare = clk_prcmu_prepare, + .unprepare = clk_prcmu_unprepare, + .enable = clk_prcmu_enable, + .disable = clk_prcmu_disable, + .is_enabled = clk_prcmu_is_enabled, + .recalc_rate = clk_prcmu_recalc_rate, + .round_rate = clk_prcmu_round_rate, + .set_rate = clk_prcmu_set_rate, +}; + +static struct clk_ops clk_prcmu_gate_ops = { + .prepare = clk_prcmu_prepare, + .unprepare = clk_prcmu_unprepare, + .enable = clk_prcmu_enable, + .disable = clk_prcmu_disable, + .is_enabled = clk_prcmu_is_enabled, + .recalc_rate = clk_prcmu_recalc_rate, +}; + +static struct clk_ops clk_prcmu_opp_gate_ops = { + .prepare = clk_prcmu_opp_prepare, + .unprepare = clk_prcmu_opp_unprepare, + .enable = clk_prcmu_enable, + .disable = clk_prcmu_disable, + .is_enabled = clk_prcmu_is_enabled, + .recalc_rate = clk_prcmu_recalc_rate, +}; + +static struct clk *clk_reg_prcmu(const char *name, + const char *parent_name, + u8 cg_sel, + unsigned long rate, + unsigned long flags, + struct clk_ops *clk_prcmu_ops) +{ + struct clk_prcmu *clk; + struct clk_init_data clk_prcmu_init; + struct clk *clk_reg; + + if (!name) { + pr_err("clk_prcmu: %s invalid arguments passed\n", __func__); + return ERR_PTR(-EINVAL); + } + + clk = kzalloc(sizeof(struct clk_prcmu), GFP_KERNEL); + if (!clk) { + pr_err("clk_prcmu: %s could not allocate clk\n", __func__); + return ERR_PTR(-ENOMEM); + } + + clk->cg_sel = cg_sel; + clk->is_enabled = 1; + /* "rate" can be used for changing the initial frequency */ + if (rate) + prcmu_set_clock_rate(cg_sel, rate); + + clk_prcmu_init.name = name; + clk_prcmu_init.ops = clk_prcmu_ops; + clk_prcmu_init.flags = flags; + clk_prcmu_init.parent_names = (parent_name ? &parent_name : NULL); + clk_prcmu_init.num_parents = (parent_name ? 1 : 0); + clk->hw.init = &clk_prcmu_init; + + clk_reg = clk_register(NULL, &clk->hw); + if (IS_ERR_OR_NULL(clk_reg)) + goto free_clk; + + return clk_reg; + +free_clk: + kfree(clk); + pr_err("clk_prcmu: %s failed to register clk\n", __func__); + return ERR_PTR(-ENOMEM); +} + +struct clk *clk_reg_prcmu_scalable(const char *name, + const char *parent_name, + u8 cg_sel, + unsigned long rate, + unsigned long flags) +{ + return clk_reg_prcmu(name, parent_name, cg_sel, rate, flags, + &clk_prcmu_scalable_ops); +} + +struct clk *clk_reg_prcmu_gate(const char *name, + const char *parent_name, + u8 cg_sel, + unsigned long flags) +{ + return clk_reg_prcmu(name, parent_name, cg_sel, 0, flags, + &clk_prcmu_gate_ops); +} + +struct clk *clk_reg_prcmu_opp_gate(const char *name, + const char *parent_name, + u8 cg_sel, + unsigned long flags) +{ + return clk_reg_prcmu(name, parent_name, cg_sel, 0, flags, + &clk_prcmu_opp_gate_ops); +} |