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-rw-r--r--drivers/clk/qcom/Makefile1
-rw-r--r--drivers/clk/qcom/clk-pll.c222
-rw-r--r--drivers/clk/qcom/clk-pll.h66
3 files changed, 289 insertions, 0 deletions
diff --git a/drivers/clk/qcom/Makefile b/drivers/clk/qcom/Makefile
index f9faa8fa9392..7871e235c2b1 100644
--- a/drivers/clk/qcom/Makefile
+++ b/drivers/clk/qcom/Makefile
@@ -1,3 +1,4 @@
obj-$(CONFIG_COMMON_CLK_QCOM) += clk-qcom.o
clk-qcom-$(CONFIG_COMMON_CLK_QCOM) += clk-regmap.o
+clk-qcom-$(CONFIG_COMMON_CLK_QCOM) += clk-pll.o
diff --git a/drivers/clk/qcom/clk-pll.c b/drivers/clk/qcom/clk-pll.c
new file mode 100644
index 000000000000..0f927c538613
--- /dev/null
+++ b/drivers/clk/qcom/clk-pll.c
@@ -0,0 +1,222 @@
+/*
+ * 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"
+
+#define PLL_OUTCTRL BIT(0)
+#define PLL_BYPASSNL BIT(1)
+#define PLL_RESET_N BIT(2)
+#define PLL_LOCK_COUNT_SHIFT 8
+#define PLL_LOCK_COUNT_MASK 0x3f
+#define PLL_BIAS_COUNT_SHIFT 14
+#define PLL_BIAS_COUNT_MASK 0x3f
+#define PLL_VOTE_FSM_ENA BIT(20)
+#define PLL_VOTE_FSM_RESET BIT(21)
+
+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. */
+ ret = regmap_update_bits(pll->clkr.regmap, pll->mode_reg, PLL_OUTCTRL,
+ PLL_OUTCTRL);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+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;
+ 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;
+ }
+ return rate;
+}
+
+const struct clk_ops clk_pll_ops = {
+ .enable = clk_pll_enable,
+ .disable = clk_pll_disable,
+ .recalc_rate = clk_pll_recalc_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_get_name(pll->clkr.hw.clk);
+
+ /* 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_get_hw(__clk_get_parent(hw->clk)));
+
+ 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_set_fsm_mode(struct clk_pll *pll, struct regmap *regmap)
+{
+ u32 val;
+ u32 mask;
+
+ /* De-assert reset to FSM */
+ regmap_update_bits(regmap, pll->mode_reg, PLL_VOTE_FSM_RESET, 0);
+
+ /* Program bias count and lock count */
+ val = 1 << PLL_BIAS_COUNT_SHIFT;
+ mask = PLL_BIAS_COUNT_MASK << PLL_BIAS_COUNT_SHIFT;
+ mask |= PLL_LOCK_COUNT_MASK << PLL_LOCK_COUNT_SHIFT;
+ regmap_update_bits(regmap, pll->mode_reg, mask, val);
+
+ /* Enable PLL FSM voting */
+ regmap_update_bits(regmap, pll->mode_reg, PLL_VOTE_FSM_ENA,
+ PLL_VOTE_FSM_ENA);
+}
+
+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_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)
+ clk_pll_set_fsm_mode(pll, regmap);
+}
+EXPORT_SYMBOL_GPL(clk_pll_configure_sr_hpm_lp);
diff --git a/drivers/clk/qcom/clk-pll.h b/drivers/clk/qcom/clk-pll.h
new file mode 100644
index 000000000000..0775a99ca768
--- /dev/null
+++ b/drivers/clk/qcom/clk-pll.h
@@ -0,0 +1,66 @@
+/*
+ * 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.
+ */
+
+#ifndef __QCOM_CLK_PLL_H__
+#define __QCOM_CLK_PLL_H__
+
+#include <linux/clk-provider.h>
+#include "clk-regmap.h"
+
+/**
+ * struct clk_pll - phase locked loop (PLL)
+ * @l_reg: L register
+ * @m_reg: M register
+ * @n_reg: N register
+ * @config_reg: config register
+ * @mode_reg: mode register
+ * @status_reg: status register
+ * @status_bit: ANDed with @status_reg to determine if PLL is enabled
+ * @hw: handle between common and hardware-specific interfaces
+ */
+struct clk_pll {
+ u32 l_reg;
+ u32 m_reg;
+ u32 n_reg;
+ u32 config_reg;
+ u32 mode_reg;
+ u32 status_reg;
+ u8 status_bit;
+
+ struct clk_regmap clkr;
+};
+
+extern const struct clk_ops clk_pll_ops;
+extern const struct clk_ops clk_pll_vote_ops;
+
+#define to_clk_pll(_hw) container_of(to_clk_regmap(_hw), struct clk_pll, clkr)
+
+struct pll_config {
+ u16 l;
+ u32 m;
+ u32 n;
+ u32 vco_val;
+ u32 vco_mask;
+ u32 pre_div_val;
+ u32 pre_div_mask;
+ u32 post_div_val;
+ u32 post_div_mask;
+ u32 mn_ena_mask;
+ u32 main_output_mask;
+ u32 aux_output_mask;
+};
+
+void clk_pll_configure_sr_hpm_lp(struct clk_pll *pll, struct regmap *regmap,
+ const struct pll_config *config, bool fsm_mode);
+
+#endif
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