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-rw-r--r--drivers/clk/zynqmp/pll.c347
1 files changed, 347 insertions, 0 deletions
diff --git a/drivers/clk/zynqmp/pll.c b/drivers/clk/zynqmp/pll.c
new file mode 100644
index 000000000..0d3e1377b
--- /dev/null
+++ b/drivers/clk/zynqmp/pll.c
@@ -0,0 +1,347 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Zynq UltraScale+ MPSoC PLL driver
+ *
+ * Copyright (C) 2016-2018 Xilinx
+ */
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/slab.h>
+#include "clk-zynqmp.h"
+
+/**
+ * struct zynqmp_pll - PLL clock
+ * @hw: Handle between common and hardware-specific interfaces
+ * @clk_id: PLL clock ID
+ * @set_pll_mode: Whether an IOCTL_SET_PLL_FRAC_MODE request be sent to ATF
+ */
+struct zynqmp_pll {
+ struct clk_hw hw;
+ u32 clk_id;
+ bool set_pll_mode;
+};
+
+#define to_zynqmp_pll(_hw) container_of(_hw, struct zynqmp_pll, hw)
+
+#define PLL_FBDIV_MIN 25
+#define PLL_FBDIV_MAX 125
+
+#define PS_PLL_VCO_MIN 1500000000
+#define PS_PLL_VCO_MAX 3000000000UL
+
+enum pll_mode {
+ PLL_MODE_INT = 0,
+ PLL_MODE_FRAC = 1,
+ PLL_MODE_ERROR = 2,
+};
+
+#define FRAC_OFFSET 0x8
+#define PLLFCFG_FRAC_EN BIT(31)
+#define FRAC_DIV BIT(16) /* 2^16 */
+
+/**
+ * zynqmp_pll_get_mode() - Get mode of PLL
+ * @hw: Handle between common and hardware-specific interfaces
+ *
+ * Return: Mode of PLL
+ */
+static inline enum pll_mode zynqmp_pll_get_mode(struct clk_hw *hw)
+{
+ struct zynqmp_pll *clk = to_zynqmp_pll(hw);
+ u32 clk_id = clk->clk_id;
+ const char *clk_name = clk_hw_get_name(hw);
+ u32 ret_payload[PAYLOAD_ARG_CNT];
+ int ret;
+
+ ret = zynqmp_pm_get_pll_frac_mode(clk_id, ret_payload);
+ if (ret) {
+ pr_debug("%s() PLL get frac mode failed for %s, ret = %d\n",
+ __func__, clk_name, ret);
+ return PLL_MODE_ERROR;
+ }
+
+ return ret_payload[1];
+}
+
+/**
+ * zynqmp_pll_set_mode() - Set the PLL mode
+ * @hw: Handle between common and hardware-specific interfaces
+ * @on: Flag to determine the mode
+ */
+static inline void zynqmp_pll_set_mode(struct clk_hw *hw, bool on)
+{
+ struct zynqmp_pll *clk = to_zynqmp_pll(hw);
+ u32 clk_id = clk->clk_id;
+ const char *clk_name = clk_hw_get_name(hw);
+ int ret;
+ u32 mode;
+
+ if (on)
+ mode = PLL_MODE_FRAC;
+ else
+ mode = PLL_MODE_INT;
+
+ ret = zynqmp_pm_set_pll_frac_mode(clk_id, mode);
+ if (ret)
+ pr_debug("%s() PLL set frac mode failed for %s, ret = %d\n",
+ __func__, clk_name, ret);
+ else
+ clk->set_pll_mode = true;
+}
+
+/**
+ * zynqmp_pll_round_rate() - Round a clock frequency
+ * @hw: Handle between common and hardware-specific interfaces
+ * @rate: Desired clock frequency
+ * @prate: Clock frequency of parent clock
+ *
+ * Return: Frequency closest to @rate the hardware can generate
+ */
+static long zynqmp_pll_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *prate)
+{
+ u32 fbdiv;
+ u32 mult, div;
+
+ /* Let rate fall inside the range PS_PLL_VCO_MIN ~ PS_PLL_VCO_MAX */
+ if (rate > PS_PLL_VCO_MAX) {
+ div = DIV_ROUND_UP(rate, PS_PLL_VCO_MAX);
+ rate = rate / div;
+ }
+ if (rate < PS_PLL_VCO_MIN) {
+ mult = DIV_ROUND_UP(PS_PLL_VCO_MIN, rate);
+ rate = rate * mult;
+ }
+
+ fbdiv = DIV_ROUND_CLOSEST(rate, *prate);
+ if (fbdiv < PLL_FBDIV_MIN || fbdiv > PLL_FBDIV_MAX) {
+ fbdiv = clamp_t(u32, fbdiv, PLL_FBDIV_MIN, PLL_FBDIV_MAX);
+ rate = *prate * fbdiv;
+ }
+
+ return rate;
+}
+
+/**
+ * zynqmp_pll_recalc_rate() - Recalculate clock frequency
+ * @hw: Handle between common and hardware-specific interfaces
+ * @parent_rate: Clock frequency of parent clock
+ *
+ * Return: Current clock frequency or 0 in case of error
+ */
+static unsigned long zynqmp_pll_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct zynqmp_pll *clk = to_zynqmp_pll(hw);
+ u32 clk_id = clk->clk_id;
+ const char *clk_name = clk_hw_get_name(hw);
+ u32 fbdiv, data;
+ unsigned long rate, frac;
+ u32 ret_payload[PAYLOAD_ARG_CNT];
+ int ret;
+ enum pll_mode mode;
+
+ ret = zynqmp_pm_clock_getdivider(clk_id, &fbdiv);
+ if (ret) {
+ pr_debug("%s() get divider failed for %s, ret = %d\n",
+ __func__, clk_name, ret);
+ return 0ul;
+ }
+
+ mode = zynqmp_pll_get_mode(hw);
+ if (mode == PLL_MODE_ERROR)
+ return 0ul;
+
+ rate = parent_rate * fbdiv;
+ if (mode == PLL_MODE_FRAC) {
+ zynqmp_pm_get_pll_frac_data(clk_id, ret_payload);
+ data = ret_payload[1];
+ frac = (parent_rate * data) / FRAC_DIV;
+ rate = rate + frac;
+ }
+
+ return rate;
+}
+
+/**
+ * zynqmp_pll_set_rate() - Set rate of PLL
+ * @hw: Handle between common and hardware-specific interfaces
+ * @rate: Frequency of clock to be set
+ * @parent_rate: Clock frequency of parent clock
+ *
+ * Set PLL divider to set desired rate.
+ *
+ * Returns: rate which is set on success else error code
+ */
+static int zynqmp_pll_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct zynqmp_pll *clk = to_zynqmp_pll(hw);
+ u32 clk_id = clk->clk_id;
+ const char *clk_name = clk_hw_get_name(hw);
+ u32 fbdiv;
+ long rate_div, frac, m, f;
+ int ret;
+
+ rate_div = (rate * FRAC_DIV) / parent_rate;
+ f = rate_div % FRAC_DIV;
+ zynqmp_pll_set_mode(hw, !!f);
+
+ if (f) {
+ m = rate_div / FRAC_DIV;
+ m = clamp_t(u32, m, (PLL_FBDIV_MIN), (PLL_FBDIV_MAX));
+ rate = parent_rate * m;
+ frac = (parent_rate * f) / FRAC_DIV;
+
+ ret = zynqmp_pm_clock_setdivider(clk_id, m);
+ if (ret == -EUSERS)
+ WARN(1, "More than allowed devices are using the %s, which is forbidden\n",
+ clk_name);
+ else if (ret)
+ pr_debug("%s() set divider failed for %s, ret = %d\n",
+ __func__, clk_name, ret);
+ zynqmp_pm_set_pll_frac_data(clk_id, f);
+
+ return rate + frac;
+ }
+
+ fbdiv = DIV_ROUND_CLOSEST(rate, parent_rate);
+ fbdiv = clamp_t(u32, fbdiv, PLL_FBDIV_MIN, PLL_FBDIV_MAX);
+ ret = zynqmp_pm_clock_setdivider(clk_id, fbdiv);
+ if (ret)
+ pr_debug("%s() set divider failed for %s, ret = %d\n",
+ __func__, clk_name, ret);
+
+ return parent_rate * fbdiv;
+}
+
+/**
+ * zynqmp_pll_is_enabled() - Check if a clock is enabled
+ * @hw: Handle between common and hardware-specific interfaces
+ *
+ * Return: 1 if the clock is enabled, 0 otherwise
+ */
+static int zynqmp_pll_is_enabled(struct clk_hw *hw)
+{
+ struct zynqmp_pll *clk = to_zynqmp_pll(hw);
+ const char *clk_name = clk_hw_get_name(hw);
+ u32 clk_id = clk->clk_id;
+ unsigned int state;
+ int ret;
+
+ ret = zynqmp_pm_clock_getstate(clk_id, &state);
+ if (ret) {
+ pr_debug("%s() clock get state failed for %s, ret = %d\n",
+ __func__, clk_name, ret);
+ return -EIO;
+ }
+
+ return state ? 1 : 0;
+}
+
+/**
+ * zynqmp_pll_enable() - Enable clock
+ * @hw: Handle between common and hardware-specific interfaces
+ *
+ * Return: 0 on success else error code
+ */
+static int zynqmp_pll_enable(struct clk_hw *hw)
+{
+ struct zynqmp_pll *clk = to_zynqmp_pll(hw);
+ const char *clk_name = clk_hw_get_name(hw);
+ u32 clk_id = clk->clk_id;
+ int ret;
+
+ /*
+ * Don't skip enabling clock if there is an IOCTL_SET_PLL_FRAC_MODE request
+ * that has been sent to ATF.
+ */
+ if (zynqmp_pll_is_enabled(hw) && (!clk->set_pll_mode))
+ return 0;
+
+ clk->set_pll_mode = false;
+
+ ret = zynqmp_pm_clock_enable(clk_id);
+ if (ret)
+ pr_debug("%s() clock enable failed for %s, ret = %d\n",
+ __func__, clk_name, ret);
+
+ return ret;
+}
+
+/**
+ * zynqmp_pll_disable() - Disable clock
+ * @hw: Handle between common and hardware-specific interfaces
+ */
+static void zynqmp_pll_disable(struct clk_hw *hw)
+{
+ struct zynqmp_pll *clk = to_zynqmp_pll(hw);
+ const char *clk_name = clk_hw_get_name(hw);
+ u32 clk_id = clk->clk_id;
+ int ret;
+
+ if (!zynqmp_pll_is_enabled(hw))
+ return;
+
+ ret = zynqmp_pm_clock_disable(clk_id);
+ if (ret)
+ pr_debug("%s() clock disable failed for %s, ret = %d\n",
+ __func__, clk_name, ret);
+}
+
+static const struct clk_ops zynqmp_pll_ops = {
+ .enable = zynqmp_pll_enable,
+ .disable = zynqmp_pll_disable,
+ .is_enabled = zynqmp_pll_is_enabled,
+ .round_rate = zynqmp_pll_round_rate,
+ .recalc_rate = zynqmp_pll_recalc_rate,
+ .set_rate = zynqmp_pll_set_rate,
+};
+
+/**
+ * zynqmp_clk_register_pll() - Register PLL with the clock framework
+ * @name: PLL name
+ * @clk_id: Clock ID
+ * @parents: Name of this clock's parents
+ * @num_parents: Number of parents
+ * @nodes: Clock topology node
+ *
+ * Return: clock hardware to the registered clock
+ */
+struct clk_hw *zynqmp_clk_register_pll(const char *name, u32 clk_id,
+ const char * const *parents,
+ u8 num_parents,
+ const struct clock_topology *nodes)
+{
+ struct zynqmp_pll *pll;
+ struct clk_hw *hw;
+ struct clk_init_data init;
+ int ret;
+
+ init.name = name;
+ init.ops = &zynqmp_pll_ops;
+
+ init.flags = zynqmp_clk_map_common_ccf_flags(nodes->flag);
+
+ init.parent_names = parents;
+ init.num_parents = 1;
+
+ pll = kzalloc(sizeof(*pll), GFP_KERNEL);
+ if (!pll)
+ return ERR_PTR(-ENOMEM);
+
+ pll->hw.init = &init;
+ pll->clk_id = clk_id;
+
+ hw = &pll->hw;
+ ret = clk_hw_register(NULL, hw);
+ if (ret) {
+ kfree(pll);
+ return ERR_PTR(ret);
+ }
+
+ clk_hw_set_rate_range(hw, PS_PLL_VCO_MIN, PS_PLL_VCO_MAX);
+
+ return hw;
+}