--- /dev/null
+/*
+ * Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/clk/at91_pmc.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/io.h>
+#include <linux/wait.h>
+#include <linux/sched.h>
+
+#include "pmc.h"
+
+#define PROG_SOURCE_MAX 5
+#define PROG_ID_MAX 7
+
+#define PROG_STATUS_MASK(id) (1 << ((id) + 8))
+#define PROG_PRES_MASK 0x7
+#define PROG_MAX_RM9200_CSS 3
+
+struct clk_programmable_layout {
+ u8 pres_shift;
+ u8 css_mask;
+ u8 have_slck_mck;
+};
+
+struct clk_programmable {
+ struct clk_hw hw;
+ struct at91_pmc *pmc;
+ u8 id;
+ const struct clk_programmable_layout *layout;
+};
+
+#define to_clk_programmable(hw) container_of(hw, struct clk_programmable, hw)
+
+static unsigned long clk_programmable_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ u32 pres;
+ struct clk_programmable *prog = to_clk_programmable(hw);
+ struct at91_pmc *pmc = prog->pmc;
+ const struct clk_programmable_layout *layout = prog->layout;
+
+ pres = (pmc_read(pmc, AT91_PMC_PCKR(prog->id)) >> layout->pres_shift) &
+ PROG_PRES_MASK;
+ return parent_rate >> pres;
+}
+
+static long clk_programmable_determine_rate(struct clk_hw *hw,
+ unsigned long rate,
+ unsigned long min_rate,
+ unsigned long max_rate,
+ unsigned long *best_parent_rate,
+ struct clk_hw **best_parent_hw)
+{
+ struct clk *parent = NULL;
+ long best_rate = -EINVAL;
+ unsigned long parent_rate;
+ unsigned long tmp_rate;
+ int shift;
+ int i;
+
+ for (i = 0; i < __clk_get_num_parents(hw->clk); i++) {
+ parent = clk_get_parent_by_index(hw->clk, i);
+ if (!parent)
+ continue;
+
+ parent_rate = __clk_get_rate(parent);
+ for (shift = 0; shift < PROG_PRES_MASK; shift++) {
+ tmp_rate = parent_rate >> shift;
+ if (tmp_rate <= rate)
+ break;
+ }
+
+ if (tmp_rate > rate)
+ continue;
+
+ if (best_rate < 0 || (rate - tmp_rate) < (rate - best_rate)) {
+ best_rate = tmp_rate;
+ *best_parent_rate = parent_rate;
+ *best_parent_hw = __clk_get_hw(parent);
+ }
+
+ if (!best_rate)
+ break;
+ }
+
+ return best_rate;
+}
+
+static int clk_programmable_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct clk_programmable *prog = to_clk_programmable(hw);
+ const struct clk_programmable_layout *layout = prog->layout;
+ struct at91_pmc *pmc = prog->pmc;
+ u32 tmp = pmc_read(pmc, AT91_PMC_PCKR(prog->id)) & ~layout->css_mask;
+
+ if (layout->have_slck_mck)
+ tmp &= AT91_PMC_CSSMCK_MCK;
+
+ if (index > layout->css_mask) {
+ if (index > PROG_MAX_RM9200_CSS && layout->have_slck_mck) {
+ tmp |= AT91_PMC_CSSMCK_MCK;
+ return 0;
+ } else {
+ return -EINVAL;
+ }
+ }
+
+ pmc_write(pmc, AT91_PMC_PCKR(prog->id), tmp | index);
+ return 0;
+}
+
+static u8 clk_programmable_get_parent(struct clk_hw *hw)
+{
+ u32 tmp;
+ u8 ret;
+ struct clk_programmable *prog = to_clk_programmable(hw);
+ struct at91_pmc *pmc = prog->pmc;
+ const struct clk_programmable_layout *layout = prog->layout;
+
+ tmp = pmc_read(pmc, AT91_PMC_PCKR(prog->id));
+ ret = tmp & layout->css_mask;
+ if (layout->have_slck_mck && (tmp & AT91_PMC_CSSMCK_MCK) && !ret)
+ ret = PROG_MAX_RM9200_CSS + 1;
+
+ return ret;
+}
+
+static int clk_programmable_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct clk_programmable *prog = to_clk_programmable(hw);
+ struct at91_pmc *pmc = prog->pmc;
+ const struct clk_programmable_layout *layout = prog->layout;
+ unsigned long div = parent_rate / rate;
+ int shift = 0;
+ u32 tmp = pmc_read(pmc, AT91_PMC_PCKR(prog->id)) &
+ ~(PROG_PRES_MASK << layout->pres_shift);
+
+ if (!div)
+ return -EINVAL;
+
+ shift = fls(div) - 1;
+
+ if (div != (1<<shift))
+ return -EINVAL;
+
+ if (shift >= PROG_PRES_MASK)
+ return -EINVAL;
+
+ pmc_write(pmc, AT91_PMC_PCKR(prog->id),
+ tmp | (shift << layout->pres_shift));
+
+ return 0;
+}
+
+static const struct clk_ops programmable_ops = {
+ .recalc_rate = clk_programmable_recalc_rate,
+ .determine_rate = clk_programmable_determine_rate,
+ .get_parent = clk_programmable_get_parent,
+ .set_parent = clk_programmable_set_parent,
+ .set_rate = clk_programmable_set_rate,
+};
+
+static struct clk * __init
+at91_clk_register_programmable(struct at91_pmc *pmc,
+ const char *name, const char **parent_names,
+ u8 num_parents, u8 id,
+ const struct clk_programmable_layout *layout)
+{
+ struct clk_programmable *prog;
+ struct clk *clk = NULL;
+ struct clk_init_data init;
+
+ if (id > PROG_ID_MAX)
+ return ERR_PTR(-EINVAL);
+
+ prog = kzalloc(sizeof(*prog), GFP_KERNEL);
+ if (!prog)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &programmable_ops;
+ init.parent_names = parent_names;
+ init.num_parents = num_parents;
+ init.flags = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE;
+
+ prog->id = id;
+ prog->layout = layout;
+ prog->hw.init = &init;
+ prog->pmc = pmc;
+
+ clk = clk_register(NULL, &prog->hw);
+ if (IS_ERR(clk))
+ kfree(prog);
+
+ return clk;
+}
+
+static const struct clk_programmable_layout at91rm9200_programmable_layout = {
+ .pres_shift = 2,
+ .css_mask = 0x3,
+ .have_slck_mck = 0,
+};
+
+static const struct clk_programmable_layout at91sam9g45_programmable_layout = {
+ .pres_shift = 2,
+ .css_mask = 0x3,
+ .have_slck_mck = 1,
+};
+
+static const struct clk_programmable_layout at91sam9x5_programmable_layout = {
+ .pres_shift = 4,
+ .css_mask = 0x7,
+ .have_slck_mck = 0,
+};
+
+static void __init
+of_at91_clk_prog_setup(struct device_node *np, struct at91_pmc *pmc,
+ const struct clk_programmable_layout *layout)
+{
+ int num;
+ u32 id;
+ int i;
+ struct clk *clk;
+ int num_parents;
+ const char *parent_names[PROG_SOURCE_MAX];
+ const char *name;
+ struct device_node *progclknp;
+
+ num_parents = of_count_phandle_with_args(np, "clocks", "#clock-cells");
+ if (num_parents <= 0 || num_parents > PROG_SOURCE_MAX)
+ return;
+
+ for (i = 0; i < num_parents; ++i) {
+ parent_names[i] = of_clk_get_parent_name(np, i);
+ if (!parent_names[i])
+ return;
+ }
+
+ num = of_get_child_count(np);
+ if (!num || num > (PROG_ID_MAX + 1))
+ return;
+
+ for_each_child_of_node(np, progclknp) {
+ if (of_property_read_u32(progclknp, "reg", &id))
+ continue;
+
+ if (of_property_read_string(np, "clock-output-names", &name))
+ name = progclknp->name;
+
+ clk = at91_clk_register_programmable(pmc, name,
+ parent_names, num_parents,
+ id, layout);
+ if (IS_ERR(clk))
+ continue;
+
+ of_clk_add_provider(progclknp, of_clk_src_simple_get, clk);
+ }
+}
+
+
+void __init of_at91rm9200_clk_prog_setup(struct device_node *np,
+ struct at91_pmc *pmc)
+{
+ of_at91_clk_prog_setup(np, pmc, &at91rm9200_programmable_layout);
+}
+
+void __init of_at91sam9g45_clk_prog_setup(struct device_node *np,
+ struct at91_pmc *pmc)
+{
+ of_at91_clk_prog_setup(np, pmc, &at91sam9g45_programmable_layout);
+}
+
+void __init of_at91sam9x5_clk_prog_setup(struct device_node *np,
+ struct at91_pmc *pmc)
+{
+ of_at91_clk_prog_setup(np, pmc, &at91sam9x5_programmable_layout);
+}
Code Review / kvmfornfv.git / blobdiff