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-rw-r--r--drivers/clk/ti/fapll.c410
1 files changed, 410 insertions, 0 deletions
diff --git a/drivers/clk/ti/fapll.c b/drivers/clk/ti/fapll.c
new file mode 100644
index 000000000000..6ef89639a9f6
--- /dev/null
+++ b/drivers/clk/ti/fapll.c
@@ -0,0 +1,410 @@
+/*
+ * 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.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/clk/ti.h>
+#include <asm/div64.h>
+
+/* FAPLL Control Register PLL_CTRL */
+#define FAPLL_MAIN_LOCK BIT(7)
+#define FAPLL_MAIN_PLLEN BIT(3)
+#define FAPLL_MAIN_BP BIT(2)
+#define FAPLL_MAIN_LOC_CTL BIT(0)
+
+/* FAPLL powerdown register PWD */
+#define FAPLL_PWD_OFFSET 4
+
+#define MAX_FAPLL_OUTPUTS 7
+#define FAPLL_MAX_RETRIES 1000
+
+#define to_fapll(_hw) container_of(_hw, struct fapll_data, hw)
+#define to_synth(_hw) container_of(_hw, struct fapll_synth, hw)
+
+/* The bypass bit is inverted on the ddr_pll.. */
+#define fapll_is_ddr_pll(va) (((u32)(va) & 0xffff) == 0x0440)
+
+/*
+ * The audio_pll_clk1 input is hard wired to the 27MHz bypass clock,
+ * and the audio_pll_clk1 synthesizer is hardwared to 32KiHz output.
+ */
+#define is_ddr_pll_clk1(va) (((u32)(va) & 0xffff) == 0x044c)
+#define is_audio_pll_clk1(va) (((u32)(va) & 0xffff) == 0x04a8)
+
+/* Synthesizer divider register */
+#define SYNTH_LDMDIV1 BIT(8)
+
+/* Synthesizer frequency register */
+#define SYNTH_LDFREQ BIT(31)
+
+struct fapll_data {
+ struct clk_hw hw;
+ void __iomem *base;
+ const char *name;
+ struct clk *clk_ref;
+ struct clk *clk_bypass;
+ struct clk_onecell_data outputs;
+ bool bypass_bit_inverted;
+};
+
+struct fapll_synth {
+ struct clk_hw hw;
+ struct fapll_data *fd;
+ int index;
+ void __iomem *freq;
+ void __iomem *div;
+ const char *name;
+ struct clk *clk_pll;
+};
+
+static bool ti_fapll_clock_is_bypass(struct fapll_data *fd)
+{
+ u32 v = readl_relaxed(fd->base);
+
+ if (fd->bypass_bit_inverted)
+ return !(v & FAPLL_MAIN_BP);
+ else
+ return !!(v & FAPLL_MAIN_BP);
+}
+
+static int ti_fapll_enable(struct clk_hw *hw)
+{
+ struct fapll_data *fd = to_fapll(hw);
+ u32 v = readl_relaxed(fd->base);
+
+ v |= (1 << FAPLL_MAIN_PLLEN);
+ writel_relaxed(v, fd->base);
+
+ return 0;
+}
+
+static void ti_fapll_disable(struct clk_hw *hw)
+{
+ struct fapll_data *fd = to_fapll(hw);
+ u32 v = readl_relaxed(fd->base);
+
+ v &= ~(1 << FAPLL_MAIN_PLLEN);
+ writel_relaxed(v, fd->base);
+}
+
+static int ti_fapll_is_enabled(struct clk_hw *hw)
+{
+ struct fapll_data *fd = to_fapll(hw);
+ u32 v = readl_relaxed(fd->base);
+
+ return v & (1 << FAPLL_MAIN_PLLEN);
+}
+
+static unsigned long ti_fapll_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct fapll_data *fd = to_fapll(hw);
+ u32 fapll_n, fapll_p, v;
+ long long rate;
+
+ if (ti_fapll_clock_is_bypass(fd))
+ return parent_rate;
+
+ rate = parent_rate;
+
+ /* PLL pre-divider is P and multiplier is N */
+ v = readl_relaxed(fd->base);
+ fapll_p = (v >> 8) & 0xff;
+ if (fapll_p)
+ do_div(rate, fapll_p);
+ fapll_n = v >> 16;
+ if (fapll_n)
+ rate *= fapll_n;
+
+ return rate;
+}
+
+static u8 ti_fapll_get_parent(struct clk_hw *hw)
+{
+ struct fapll_data *fd = to_fapll(hw);
+
+ if (ti_fapll_clock_is_bypass(fd))
+ return 1;
+
+ return 0;
+}
+
+static struct clk_ops ti_fapll_ops = {
+ .enable = ti_fapll_enable,
+ .disable = ti_fapll_disable,
+ .is_enabled = ti_fapll_is_enabled,
+ .recalc_rate = ti_fapll_recalc_rate,
+ .get_parent = ti_fapll_get_parent,
+};
+
+static int ti_fapll_synth_enable(struct clk_hw *hw)
+{
+ struct fapll_synth *synth = to_synth(hw);
+ u32 v = readl_relaxed(synth->fd->base + FAPLL_PWD_OFFSET);
+
+ v &= ~(1 << synth->index);
+ writel_relaxed(v, synth->fd->base + FAPLL_PWD_OFFSET);
+
+ return 0;
+}
+
+static void ti_fapll_synth_disable(struct clk_hw *hw)
+{
+ struct fapll_synth *synth = to_synth(hw);
+ u32 v = readl_relaxed(synth->fd->base + FAPLL_PWD_OFFSET);
+
+ v |= 1 << synth->index;
+ writel_relaxed(v, synth->fd->base + FAPLL_PWD_OFFSET);
+}
+
+static int ti_fapll_synth_is_enabled(struct clk_hw *hw)
+{
+ struct fapll_synth *synth = to_synth(hw);
+ u32 v = readl_relaxed(synth->fd->base + FAPLL_PWD_OFFSET);
+
+ return !(v & (1 << synth->index));
+}
+
+/*
+ * See dm816x TRM chapter 1.10.3 Flying Adder PLL fore more info
+ */
+static unsigned long ti_fapll_synth_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct fapll_synth *synth = to_synth(hw);
+ u32 synth_div_m;
+ long long rate;
+
+ /* The audio_pll_clk1 is hardwired to produce 32.768KiHz clock */
+ if (!synth->div)
+ return 32768;
+
+ /*
+ * PLL in bypass sets the synths in bypass mode too. The PLL rate
+ * can be also be set to 27MHz, so we can't use parent_rate to
+ * check for bypass mode.
+ */
+ if (ti_fapll_clock_is_bypass(synth->fd))
+ return parent_rate;
+
+ rate = parent_rate;
+
+ /*
+ * Synth frequency integer and fractional divider.
+ * Note that the phase output K is 8, so the result needs
+ * to be multiplied by 8.
+ */
+ if (synth->freq) {
+ u32 v, synth_int_div, synth_frac_div, synth_div_freq;
+
+ v = readl_relaxed(synth->freq);
+ synth_int_div = (v >> 24) & 0xf;
+ synth_frac_div = v & 0xffffff;
+ synth_div_freq = (synth_int_div * 10000000) + synth_frac_div;
+ rate *= 10000000;
+ do_div(rate, synth_div_freq);
+ rate *= 8;
+ }
+
+ /* Synth ost-divider M */
+ synth_div_m = readl_relaxed(synth->div) & 0xff;
+ do_div(rate, synth_div_m);
+
+ return rate;
+}
+
+static struct clk_ops ti_fapll_synt_ops = {
+ .enable = ti_fapll_synth_enable,
+ .disable = ti_fapll_synth_disable,
+ .is_enabled = ti_fapll_synth_is_enabled,
+ .recalc_rate = ti_fapll_synth_recalc_rate,
+};
+
+static struct clk * __init ti_fapll_synth_setup(struct fapll_data *fd,
+ void __iomem *freq,
+ void __iomem *div,
+ int index,
+ const char *name,
+ const char *parent,
+ struct clk *pll_clk)
+{
+ struct clk_init_data *init;
+ struct fapll_synth *synth;
+
+ init = kzalloc(sizeof(*init), GFP_KERNEL);
+ if (!init)
+ return ERR_PTR(-ENOMEM);
+
+ init->ops = &ti_fapll_synt_ops;
+ init->name = name;
+ init->parent_names = &parent;
+ init->num_parents = 1;
+
+ synth = kzalloc(sizeof(*synth), GFP_KERNEL);
+ if (!synth)
+ goto free;
+
+ synth->fd = fd;
+ synth->index = index;
+ synth->freq = freq;
+ synth->div = div;
+ synth->name = name;
+ synth->hw.init = init;
+ synth->clk_pll = pll_clk;
+
+ return clk_register(NULL, &synth->hw);
+
+free:
+ kfree(synth);
+ kfree(init);
+
+ return ERR_PTR(-ENOMEM);
+}
+
+static void __init ti_fapll_setup(struct device_node *node)
+{
+ struct fapll_data *fd;
+ struct clk_init_data *init = NULL;
+ const char *parent_name[2];
+ struct clk *pll_clk;
+ int i;
+
+ fd = kzalloc(sizeof(*fd), GFP_KERNEL);
+ if (!fd)
+ return;
+
+ fd->outputs.clks = kzalloc(sizeof(struct clk *) *
+ MAX_FAPLL_OUTPUTS + 1,
+ GFP_KERNEL);
+ if (!fd->outputs.clks)
+ goto free;
+
+ init = kzalloc(sizeof(*init), GFP_KERNEL);
+ if (!init)
+ goto free;
+
+ init->ops = &ti_fapll_ops;
+ init->name = node->name;
+
+ init->num_parents = of_clk_get_parent_count(node);
+ if (init->num_parents != 2) {
+ pr_err("%s must have two parents\n", node->name);
+ goto free;
+ }
+
+ parent_name[0] = of_clk_get_parent_name(node, 0);
+ parent_name[1] = of_clk_get_parent_name(node, 1);
+ init->parent_names = parent_name;
+
+ fd->clk_ref = of_clk_get(node, 0);
+ if (IS_ERR(fd->clk_ref)) {
+ pr_err("%s could not get clk_ref\n", node->name);
+ goto free;
+ }
+
+ fd->clk_bypass = of_clk_get(node, 1);
+ if (IS_ERR(fd->clk_bypass)) {
+ pr_err("%s could not get clk_bypass\n", node->name);
+ goto free;
+ }
+
+ fd->base = of_iomap(node, 0);
+ if (!fd->base) {
+ pr_err("%s could not get IO base\n", node->name);
+ goto free;
+ }
+
+ if (fapll_is_ddr_pll(fd->base))
+ fd->bypass_bit_inverted = true;
+
+ fd->name = node->name;
+ fd->hw.init = init;
+
+ /* Register the parent PLL */
+ pll_clk = clk_register(NULL, &fd->hw);
+ if (IS_ERR(pll_clk))
+ goto unmap;
+
+ fd->outputs.clks[0] = pll_clk;
+ fd->outputs.clk_num++;
+
+ /*
+ * Set up the child synthesizers starting at index 1 as the
+ * PLL output is at index 0. We need to check the clock-indices
+ * for numbering in case there are holes in the synth mapping,
+ * and then probe the synth register to see if it has a FREQ
+ * register available.
+ */
+ for (i = 0; i < MAX_FAPLL_OUTPUTS; i++) {
+ const char *output_name;
+ void __iomem *freq, *div;
+ struct clk *synth_clk;
+ int output_instance;
+ u32 v;
+
+ if (of_property_read_string_index(node, "clock-output-names",
+ i, &output_name))
+ continue;
+
+ if (of_property_read_u32_index(node, "clock-indices", i,
+ &output_instance))
+ output_instance = i;
+
+ freq = fd->base + (output_instance * 8);
+ div = freq + 4;
+
+ /* Check for hardwired audio_pll_clk1 */
+ if (is_audio_pll_clk1(freq)) {
+ freq = 0;
+ div = 0;
+ } else {
+ /* Does the synthesizer have a FREQ register? */
+ v = readl_relaxed(freq);
+ if (!v)
+ freq = 0;
+ }
+ synth_clk = ti_fapll_synth_setup(fd, freq, div, output_instance,
+ output_name, node->name,
+ pll_clk);
+ if (IS_ERR(synth_clk))
+ continue;
+
+ fd->outputs.clks[output_instance] = synth_clk;
+ fd->outputs.clk_num++;
+
+ clk_register_clkdev(synth_clk, output_name, NULL);
+ }
+
+ /* Register the child synthesizers as the FAPLL outputs */
+ of_clk_add_provider(node, of_clk_src_onecell_get, &fd->outputs);
+ /* Add clock alias for the outputs */
+
+ kfree(init);
+
+ return;
+
+unmap:
+ iounmap(fd->base);
+free:
+ if (fd->clk_bypass)
+ clk_put(fd->clk_bypass);
+ if (fd->clk_ref)
+ clk_put(fd->clk_ref);
+ kfree(fd->outputs.clks);
+ kfree(fd);
+ kfree(init);
+}
+
+CLK_OF_DECLARE(ti_fapll_clock, "ti,dm816-fapll-clock", ti_fapll_setup);
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