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path: root/drivers/clk/qcom/clk-pll.c
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-rw-r--r--drivers/clk/qcom/clk-pll.c344
1 files changed, 344 insertions, 0 deletions
diff --git a/drivers/clk/qcom/clk-pll.c b/drivers/clk/qcom/clk-pll.c
new file mode 100644
index 000000000..cb6cb8710
--- /dev/null
+++ b/drivers/clk/qcom/clk-pll.c
@@ -0,0 +1,344 @@
+/*
+ * Copyright (c) 2013, The Linux Foundation. All rights reserved.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/bitops.h>
+#include <linux/err.h>
+#include <linux/bug.h>
+#include <linux/delay.h>
+#include <linux/export.h>
+#include <linux/clk-provider.h>
+#include <linux/regmap.h>
+
+#include <asm/div64.h>
+
+#include "clk-pll.h"
+#include "common.h"
+
+#define PLL_OUTCTRL BIT(0)
+#define PLL_BYPASSNL BIT(1)
+#define PLL_RESET_N BIT(2)
+
+static int clk_pll_enable(struct clk_hw *hw)
+{
+ struct clk_pll *pll = to_clk_pll(hw);
+ int ret;
+ u32 mask, val;
+
+ mask = PLL_OUTCTRL | PLL_RESET_N | PLL_BYPASSNL;
+ ret = regmap_read(pll->clkr.regmap, pll->mode_reg, &val);
+ if (ret)
+ return ret;
+
+ /* Skip if already enabled or in FSM mode */
+ if ((val & mask) == mask || val & PLL_VOTE_FSM_ENA)
+ return 0;
+
+ /* Disable PLL bypass mode. */
+ ret = regmap_update_bits(pll->clkr.regmap, pll->mode_reg, PLL_BYPASSNL,
+ PLL_BYPASSNL);
+ if (ret)
+ return ret;
+
+ /*
+ * H/W requires a 5us delay between disabling the bypass and
+ * de-asserting the reset. Delay 10us just to be safe.
+ */
+ udelay(10);
+
+ /* De-assert active-low PLL reset. */
+ ret = regmap_update_bits(pll->clkr.regmap, pll->mode_reg, PLL_RESET_N,
+ PLL_RESET_N);
+ if (ret)
+ return ret;
+
+ /* Wait until PLL is locked. */
+ udelay(50);
+
+ /* Enable PLL output. */
+ return regmap_update_bits(pll->clkr.regmap, pll->mode_reg, PLL_OUTCTRL,
+ PLL_OUTCTRL);
+}
+
+static void clk_pll_disable(struct clk_hw *hw)
+{
+ struct clk_pll *pll = to_clk_pll(hw);
+ u32 mask;
+ u32 val;
+
+ regmap_read(pll->clkr.regmap, pll->mode_reg, &val);
+ /* Skip if in FSM mode */
+ if (val & PLL_VOTE_FSM_ENA)
+ return;
+ mask = PLL_OUTCTRL | PLL_RESET_N | PLL_BYPASSNL;
+ regmap_update_bits(pll->clkr.regmap, pll->mode_reg, mask, 0);
+}
+
+static unsigned long
+clk_pll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
+{
+ struct clk_pll *pll = to_clk_pll(hw);
+ u32 l, m, n, config;
+ unsigned long rate;
+ u64 tmp;
+
+ regmap_read(pll->clkr.regmap, pll->l_reg, &l);
+ regmap_read(pll->clkr.regmap, pll->m_reg, &m);
+ regmap_read(pll->clkr.regmap, pll->n_reg, &n);
+
+ l &= 0x3ff;
+ m &= 0x7ffff;
+ n &= 0x7ffff;
+
+ rate = parent_rate * l;
+ if (n) {
+ tmp = parent_rate;
+ tmp *= m;
+ do_div(tmp, n);
+ rate += tmp;
+ }
+ if (pll->post_div_width) {
+ regmap_read(pll->clkr.regmap, pll->config_reg, &config);
+ config >>= pll->post_div_shift;
+ config &= BIT(pll->post_div_width) - 1;
+ rate /= config + 1;
+ }
+
+ return rate;
+}
+
+static const
+struct pll_freq_tbl *find_freq(const struct pll_freq_tbl *f, unsigned long rate)
+{
+ if (!f)
+ return NULL;
+
+ for (; f->freq; f++)
+ if (rate <= f->freq)
+ return f;
+
+ return NULL;
+}
+
+static int
+clk_pll_determine_rate(struct clk_hw *hw, struct clk_rate_request *req)
+{
+ struct clk_pll *pll = to_clk_pll(hw);
+ const struct pll_freq_tbl *f;
+
+ f = find_freq(pll->freq_tbl, req->rate);
+ if (!f)
+ req->rate = clk_pll_recalc_rate(hw, req->best_parent_rate);
+ else
+ req->rate = f->freq;
+
+ return 0;
+}
+
+static int
+clk_pll_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long p_rate)
+{
+ struct clk_pll *pll = to_clk_pll(hw);
+ const struct pll_freq_tbl *f;
+ bool enabled;
+ u32 mode;
+ u32 enable_mask = PLL_OUTCTRL | PLL_BYPASSNL | PLL_RESET_N;
+
+ f = find_freq(pll->freq_tbl, rate);
+ if (!f)
+ return -EINVAL;
+
+ regmap_read(pll->clkr.regmap, pll->mode_reg, &mode);
+ enabled = (mode & enable_mask) == enable_mask;
+
+ if (enabled)
+ clk_pll_disable(hw);
+
+ regmap_update_bits(pll->clkr.regmap, pll->l_reg, 0x3ff, f->l);
+ regmap_update_bits(pll->clkr.regmap, pll->m_reg, 0x7ffff, f->m);
+ regmap_update_bits(pll->clkr.regmap, pll->n_reg, 0x7ffff, f->n);
+ regmap_write(pll->clkr.regmap, pll->config_reg, f->ibits);
+
+ if (enabled)
+ clk_pll_enable(hw);
+
+ return 0;
+}
+
+const struct clk_ops clk_pll_ops = {
+ .enable = clk_pll_enable,
+ .disable = clk_pll_disable,
+ .recalc_rate = clk_pll_recalc_rate,
+ .determine_rate = clk_pll_determine_rate,
+ .set_rate = clk_pll_set_rate,
+};
+EXPORT_SYMBOL_GPL(clk_pll_ops);
+
+static int wait_for_pll(struct clk_pll *pll)
+{
+ u32 val;
+ int count;
+ int ret;
+ const char *name = clk_hw_get_name(&pll->clkr.hw);
+
+ /* Wait for pll to enable. */
+ for (count = 200; count > 0; count--) {
+ ret = regmap_read(pll->clkr.regmap, pll->status_reg, &val);
+ if (ret)
+ return ret;
+ if (val & BIT(pll->status_bit))
+ return 0;
+ udelay(1);
+ }
+
+ WARN(1, "%s didn't enable after voting for it!\n", name);
+ return -ETIMEDOUT;
+}
+
+static int clk_pll_vote_enable(struct clk_hw *hw)
+{
+ int ret;
+ struct clk_pll *p = to_clk_pll(clk_hw_get_parent(hw));
+
+ ret = clk_enable_regmap(hw);
+ if (ret)
+ return ret;
+
+ return wait_for_pll(p);
+}
+
+const struct clk_ops clk_pll_vote_ops = {
+ .enable = clk_pll_vote_enable,
+ .disable = clk_disable_regmap,
+};
+EXPORT_SYMBOL_GPL(clk_pll_vote_ops);
+
+static void clk_pll_configure(struct clk_pll *pll, struct regmap *regmap,
+ const struct pll_config *config)
+{
+ u32 val;
+ u32 mask;
+
+ regmap_write(regmap, pll->l_reg, config->l);
+ regmap_write(regmap, pll->m_reg, config->m);
+ regmap_write(regmap, pll->n_reg, config->n);
+
+ val = config->vco_val;
+ val |= config->pre_div_val;
+ val |= config->post_div_val;
+ val |= config->mn_ena_mask;
+ val |= config->main_output_mask;
+ val |= config->aux_output_mask;
+
+ mask = config->vco_mask;
+ mask |= config->pre_div_mask;
+ mask |= config->post_div_mask;
+ mask |= config->mn_ena_mask;
+ mask |= config->main_output_mask;
+ mask |= config->aux_output_mask;
+
+ regmap_update_bits(regmap, pll->config_reg, mask, val);
+}
+
+void clk_pll_configure_sr(struct clk_pll *pll, struct regmap *regmap,
+ const struct pll_config *config, bool fsm_mode)
+{
+ clk_pll_configure(pll, regmap, config);
+ if (fsm_mode)
+ qcom_pll_set_fsm_mode(regmap, pll->mode_reg, 1, 8);
+}
+EXPORT_SYMBOL_GPL(clk_pll_configure_sr);
+
+void clk_pll_configure_sr_hpm_lp(struct clk_pll *pll, struct regmap *regmap,
+ const struct pll_config *config, bool fsm_mode)
+{
+ clk_pll_configure(pll, regmap, config);
+ if (fsm_mode)
+ qcom_pll_set_fsm_mode(regmap, pll->mode_reg, 1, 0);
+}
+EXPORT_SYMBOL_GPL(clk_pll_configure_sr_hpm_lp);
+
+static int clk_pll_sr2_enable(struct clk_hw *hw)
+{
+ struct clk_pll *pll = to_clk_pll(hw);
+ int ret;
+ u32 mode;
+
+ ret = regmap_read(pll->clkr.regmap, pll->mode_reg, &mode);
+ if (ret)
+ return ret;
+
+ /* Disable PLL bypass mode. */
+ ret = regmap_update_bits(pll->clkr.regmap, pll->mode_reg, PLL_BYPASSNL,
+ PLL_BYPASSNL);
+ if (ret)
+ return ret;
+
+ /*
+ * H/W requires a 5us delay between disabling the bypass and
+ * de-asserting the reset. Delay 10us just to be safe.
+ */
+ udelay(10);
+
+ /* De-assert active-low PLL reset. */
+ ret = regmap_update_bits(pll->clkr.regmap, pll->mode_reg, PLL_RESET_N,
+ PLL_RESET_N);
+ if (ret)
+ return ret;
+
+ ret = wait_for_pll(pll);
+ if (ret)
+ return ret;
+
+ /* Enable PLL output. */
+ return regmap_update_bits(pll->clkr.regmap, pll->mode_reg, PLL_OUTCTRL,
+ PLL_OUTCTRL);
+}
+
+static int
+clk_pll_sr2_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long prate)
+{
+ struct clk_pll *pll = to_clk_pll(hw);
+ const struct pll_freq_tbl *f;
+ bool enabled;
+ u32 mode;
+ u32 enable_mask = PLL_OUTCTRL | PLL_BYPASSNL | PLL_RESET_N;
+
+ f = find_freq(pll->freq_tbl, rate);
+ if (!f)
+ return -EINVAL;
+
+ regmap_read(pll->clkr.regmap, pll->mode_reg, &mode);
+ enabled = (mode & enable_mask) == enable_mask;
+
+ if (enabled)
+ clk_pll_disable(hw);
+
+ regmap_update_bits(pll->clkr.regmap, pll->l_reg, 0x3ff, f->l);
+ regmap_update_bits(pll->clkr.regmap, pll->m_reg, 0x7ffff, f->m);
+ regmap_update_bits(pll->clkr.regmap, pll->n_reg, 0x7ffff, f->n);
+
+ if (enabled)
+ clk_pll_sr2_enable(hw);
+
+ return 0;
+}
+
+const struct clk_ops clk_pll_sr2_ops = {
+ .enable = clk_pll_sr2_enable,
+ .disable = clk_pll_disable,
+ .set_rate = clk_pll_sr2_set_rate,
+ .recalc_rate = clk_pll_recalc_rate,
+ .determine_rate = clk_pll_determine_rate,
+};
+EXPORT_SYMBOL_GPL(clk_pll_sr2_ops);