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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/drivers/clk/ti/fapll.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/drivers/clk/ti/fapll.c')
-rw-r--r--kernel/drivers/clk/ti/fapll.c664
1 files changed, 664 insertions, 0 deletions
diff --git a/kernel/drivers/clk/ti/fapll.c b/kernel/drivers/clk/ti/fapll.c
new file mode 100644
index 000000000..ffcd8e09e
--- /dev/null
+++ b/kernel/drivers/clk/ti/fapll.c
@@ -0,0 +1,664 @@
+/*
+ * 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/err.h>
+#include <linux/math64.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/clk/ti.h>
+
+/* FAPLL Control Register PLL_CTRL */
+#define FAPLL_MAIN_MULT_N_SHIFT 16
+#define FAPLL_MAIN_DIV_P_SHIFT 8
+#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)
+
+#define FAPLL_MAIN_MAX_MULT_N 0xffff
+#define FAPLL_MAIN_MAX_DIV_P 0xff
+#define FAPLL_MAIN_CLEAR_MASK \
+ ((FAPLL_MAIN_MAX_MULT_N << FAPLL_MAIN_MULT_N_SHIFT) | \
+ (FAPLL_MAIN_DIV_P_SHIFT << FAPLL_MAIN_DIV_P_SHIFT) | \
+ FAPLL_MAIN_LOC_CTL)
+
+/* 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)
+
+#define SYNTH_PHASE_K 8
+#define SYNTH_MAX_INT_DIV 0xf
+#define SYNTH_MAX_DIV_M 0xff
+
+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 void ti_fapll_set_bypass(struct fapll_data *fd)
+{
+ u32 v = readl_relaxed(fd->base);
+
+ if (fd->bypass_bit_inverted)
+ v &= ~FAPLL_MAIN_BP;
+ else
+ v |= FAPLL_MAIN_BP;
+ writel_relaxed(v, fd->base);
+}
+
+static void ti_fapll_clear_bypass(struct fapll_data *fd)
+{
+ u32 v = readl_relaxed(fd->base);
+
+ if (fd->bypass_bit_inverted)
+ v |= FAPLL_MAIN_BP;
+ else
+ v &= ~FAPLL_MAIN_BP;
+ writel_relaxed(v, fd->base);
+}
+
+static int ti_fapll_wait_lock(struct fapll_data *fd)
+{
+ int retries = FAPLL_MAX_RETRIES;
+ u32 v;
+
+ while ((v = readl_relaxed(fd->base))) {
+ if (v & FAPLL_MAIN_LOCK)
+ return 0;
+
+ if (retries-- <= 0)
+ break;
+
+ udelay(1);
+ }
+
+ pr_err("%s failed to lock\n", fd->name);
+
+ return -ETIMEDOUT;
+}
+
+static int ti_fapll_enable(struct clk_hw *hw)
+{
+ struct fapll_data *fd = to_fapll(hw);
+ u32 v = readl_relaxed(fd->base);
+
+ v |= FAPLL_MAIN_PLLEN;
+ writel_relaxed(v, fd->base);
+ ti_fapll_wait_lock(fd);
+
+ 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 &= ~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 & 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 int ti_fapll_set_div_mult(unsigned long rate,
+ unsigned long parent_rate,
+ u32 *pre_div_p, u32 *mult_n)
+{
+ /*
+ * So far no luck getting decent clock with PLL divider,
+ * PLL does not seem to lock and the signal does not look
+ * right. It seems the divider can only be used together
+ * with the multiplier?
+ */
+ if (rate < parent_rate) {
+ pr_warn("FAPLL main divider rates unsupported\n");
+ return -EINVAL;
+ }
+
+ *mult_n = rate / parent_rate;
+ if (*mult_n > FAPLL_MAIN_MAX_MULT_N)
+ return -EINVAL;
+ *pre_div_p = 1;
+
+ return 0;
+}
+
+static long ti_fapll_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ u32 pre_div_p, mult_n;
+ int error;
+
+ if (!rate)
+ return -EINVAL;
+
+ error = ti_fapll_set_div_mult(rate, *parent_rate,
+ &pre_div_p, &mult_n);
+ if (error)
+ return error;
+
+ rate = *parent_rate / pre_div_p;
+ rate *= mult_n;
+
+ return rate;
+}
+
+static int ti_fapll_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct fapll_data *fd = to_fapll(hw);
+ u32 pre_div_p, mult_n, v;
+ int error;
+
+ if (!rate)
+ return -EINVAL;
+
+ error = ti_fapll_set_div_mult(rate, parent_rate,
+ &pre_div_p, &mult_n);
+ if (error)
+ return error;
+
+ ti_fapll_set_bypass(fd);
+ v = readl_relaxed(fd->base);
+ v &= ~FAPLL_MAIN_CLEAR_MASK;
+ v |= pre_div_p << FAPLL_MAIN_DIV_P_SHIFT;
+ v |= mult_n << FAPLL_MAIN_MULT_N_SHIFT;
+ writel_relaxed(v, fd->base);
+ if (ti_fapll_is_enabled(hw))
+ ti_fapll_wait_lock(fd);
+ ti_fapll_clear_bypass(fd);
+
+ 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,
+ .round_rate = ti_fapll_round_rate,
+ .set_rate = ti_fapll_set_rate,
+};
+
+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 SYNTH_PHASE_K.
+ */
+ 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 *= SYNTH_PHASE_K;
+ }
+
+ /* Synth post-divider M */
+ synth_div_m = readl_relaxed(synth->div) & SYNTH_MAX_DIV_M;
+
+ return DIV_ROUND_UP_ULL(rate, synth_div_m);
+}
+
+static unsigned long ti_fapll_synth_get_frac_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct fapll_synth *synth = to_synth(hw);
+ unsigned long current_rate, frac_rate;
+ u32 post_div_m;
+
+ current_rate = ti_fapll_synth_recalc_rate(hw, parent_rate);
+ post_div_m = readl_relaxed(synth->div) & SYNTH_MAX_DIV_M;
+ frac_rate = current_rate * post_div_m;
+
+ return frac_rate;
+}
+
+static u32 ti_fapll_synth_set_frac_rate(struct fapll_synth *synth,
+ unsigned long rate,
+ unsigned long parent_rate)
+{
+ u32 post_div_m, synth_int_div = 0, synth_frac_div = 0, v;
+
+ post_div_m = DIV_ROUND_UP_ULL((u64)parent_rate * SYNTH_PHASE_K, rate);
+ post_div_m = post_div_m / SYNTH_MAX_INT_DIV;
+ if (post_div_m > SYNTH_MAX_DIV_M)
+ return -EINVAL;
+ if (!post_div_m)
+ post_div_m = 1;
+
+ for (; post_div_m < SYNTH_MAX_DIV_M; post_div_m++) {
+ synth_int_div = DIV_ROUND_UP_ULL((u64)parent_rate *
+ SYNTH_PHASE_K *
+ 10000000,
+ rate * post_div_m);
+ synth_frac_div = synth_int_div % 10000000;
+ synth_int_div /= 10000000;
+
+ if (synth_int_div <= SYNTH_MAX_INT_DIV)
+ break;
+ }
+
+ if (synth_int_div > SYNTH_MAX_INT_DIV)
+ return -EINVAL;
+
+ v = readl_relaxed(synth->freq);
+ v &= ~0x1fffffff;
+ v |= (synth_int_div & SYNTH_MAX_INT_DIV) << 24;
+ v |= (synth_frac_div & 0xffffff);
+ v |= SYNTH_LDFREQ;
+ writel_relaxed(v, synth->freq);
+
+ return post_div_m;
+}
+
+static long ti_fapll_synth_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ struct fapll_synth *synth = to_synth(hw);
+ struct fapll_data *fd = synth->fd;
+ unsigned long r;
+
+ if (ti_fapll_clock_is_bypass(fd) || !synth->div || !rate)
+ return -EINVAL;
+
+ /* Only post divider m available with no fractional divider? */
+ if (!synth->freq) {
+ unsigned long frac_rate;
+ u32 synth_post_div_m;
+
+ frac_rate = ti_fapll_synth_get_frac_rate(hw, *parent_rate);
+ synth_post_div_m = DIV_ROUND_UP(frac_rate, rate);
+ r = DIV_ROUND_UP(frac_rate, synth_post_div_m);
+ goto out;
+ }
+
+ r = *parent_rate * SYNTH_PHASE_K;
+ if (rate > r)
+ goto out;
+
+ r = DIV_ROUND_UP_ULL(r, SYNTH_MAX_INT_DIV * SYNTH_MAX_DIV_M);
+ if (rate < r)
+ goto out;
+
+ r = rate;
+out:
+ return r;
+}
+
+static int ti_fapll_synth_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct fapll_synth *synth = to_synth(hw);
+ struct fapll_data *fd = synth->fd;
+ unsigned long frac_rate, post_rate = 0;
+ u32 post_div_m = 0, v;
+
+ if (ti_fapll_clock_is_bypass(fd) || !synth->div || !rate)
+ return -EINVAL;
+
+ /* Produce the rate with just post divider M? */
+ frac_rate = ti_fapll_synth_get_frac_rate(hw, parent_rate);
+ if (frac_rate < rate) {
+ if (!synth->freq)
+ return -EINVAL;
+ } else {
+ post_div_m = DIV_ROUND_UP(frac_rate, rate);
+ if (post_div_m && (post_div_m <= SYNTH_MAX_DIV_M))
+ post_rate = DIV_ROUND_UP(frac_rate, post_div_m);
+ if (!synth->freq && !post_rate)
+ return -EINVAL;
+ }
+
+ /* Need to recalculate the fractional divider? */
+ if ((post_rate != rate) && synth->freq)
+ post_div_m = ti_fapll_synth_set_frac_rate(synth,
+ rate,
+ parent_rate);
+
+ v = readl_relaxed(synth->div);
+ v &= ~SYNTH_MAX_DIV_M;
+ v |= post_div_m;
+ v |= SYNTH_LDMDIV1;
+ writel_relaxed(v, synth->div);
+
+ return 0;
+}
+
+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,
+ .round_rate = ti_fapll_synth_round_rate,
+ .set_rate = ti_fapll_synth_set_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);