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authorSantosh Shilimkar <santosh.shilimkar@ti.com>2013-09-25 21:18:13 -0400
committerMike Turquette <mturquette@linaro.org>2013-10-07 18:16:21 -0700
commitb9e0d40c0d83805bc6feb86d602e73f2cdcb17f9 (patch)
treebab61165c96cd1b762250d7de593b88580fd43a4 /drivers/clk
parent938cc3a14ca0d921165c741fb10d8defba203dde (diff)
clk: keystone: add Keystone PLL clock driver
Add the driver for the PLL IPs found on Keystone 2 devices. The PLL IP typically has a multiplier, a divider and a post-divider. The PLL IPs like ARMPLL, DDRPLL and PAPLL are controlled by the memory mapped register where as the Main PLL is controlled by a PLL controller and memory map registers. Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
Diffstat (limited to 'drivers/clk')
-rw-r--r--drivers/clk/keystone/pll.c305
1 files changed, 305 insertions, 0 deletions
diff --git a/drivers/clk/keystone/pll.c b/drivers/clk/keystone/pll.c
new file mode 100644
index 000000000000..47a1bd9f1726
--- /dev/null
+++ b/drivers/clk/keystone/pll.c
@@ -0,0 +1,305 @@
+/*
+ * PLL clock driver for Keystone devices
+ *
+ * Copyright (C) 2013 Texas Instruments Inc.
+ * Murali Karicheri <m-karicheri2@ti.com>
+ * Santosh Shilimkar <santosh.shilimkar@ti.com>
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/of_address.h>
+#include <linux/of.h>
+#include <linux/module.h>
+
+#define PLLM_LOW_MASK 0x3f
+#define PLLM_HIGH_MASK 0x7ffc0
+#define MAIN_PLLM_HIGH_MASK 0x7f000
+#define PLLM_HIGH_SHIFT 6
+#define PLLD_MASK 0x3f
+
+/**
+ * struct clk_pll_data - pll data structure
+ * @has_pllctrl: If set to non zero, lower 6 bits of multiplier is in pllm
+ * register of pll controller, else it is in the pll_ctrl0((bit 11-6)
+ * @phy_pllm: Physical address of PLLM in pll controller. Used when
+ * has_pllctrl is non zero.
+ * @phy_pll_ctl0: Physical address of PLL ctrl0. This could be that of
+ * Main PLL or any other PLLs in the device such as ARM PLL, DDR PLL
+ * or PA PLL available on keystone2. These PLLs are controlled by
+ * this register. Main PLL is controlled by a PLL controller.
+ * @pllm: PLL register map address
+ * @pll_ctl0: PLL controller map address
+ * @pllm_lower_mask: multiplier lower mask
+ * @pllm_upper_mask: multiplier upper mask
+ * @pllm_upper_shift: multiplier upper shift
+ * @plld_mask: divider mask
+ * @postdiv: Post divider
+ */
+struct clk_pll_data {
+ bool has_pllctrl;
+ u32 phy_pllm;
+ u32 phy_pll_ctl0;
+ void __iomem *pllm;
+ void __iomem *pll_ctl0;
+ u32 pllm_lower_mask;
+ u32 pllm_upper_mask;
+ u32 pllm_upper_shift;
+ u32 plld_mask;
+ u32 postdiv;
+};
+
+/**
+ * struct clk_pll - Main pll clock
+ * @hw: clk_hw for the pll
+ * @pll_data: PLL driver specific data
+ */
+struct clk_pll {
+ struct clk_hw hw;
+ struct clk_pll_data *pll_data;
+};
+
+#define to_clk_pll(_hw) container_of(_hw, struct clk_pll, hw)
+
+static unsigned long clk_pllclk_recalc(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_pll *pll = to_clk_pll(hw);
+ struct clk_pll_data *pll_data = pll->pll_data;
+ unsigned long rate = parent_rate;
+ u32 mult = 0, prediv, postdiv, val;
+
+ /*
+ * get bits 0-5 of multiplier from pllctrl PLLM register
+ * if has_pllctrl is non zero
+ */
+ if (pll_data->has_pllctrl) {
+ val = readl(pll_data->pllm);
+ mult = (val & pll_data->pllm_lower_mask);
+ }
+
+ /* bit6-12 of PLLM is in Main PLL control register */
+ val = readl(pll_data->pll_ctl0);
+ mult |= ((val & pll_data->pllm_upper_mask)
+ >> pll_data->pllm_upper_shift);
+ prediv = (val & pll_data->plld_mask);
+ postdiv = pll_data->postdiv;
+
+ rate /= (prediv + 1);
+ rate = (rate * (mult + 1));
+ rate /= postdiv;
+
+ return rate;
+}
+
+static const struct clk_ops clk_pll_ops = {
+ .recalc_rate = clk_pllclk_recalc,
+};
+
+static struct clk *clk_register_pll(struct device *dev,
+ const char *name,
+ const char *parent_name,
+ struct clk_pll_data *pll_data)
+{
+ struct clk_init_data init;
+ struct clk_pll *pll;
+ struct clk *clk;
+
+ pll = kzalloc(sizeof(*pll), GFP_KERNEL);
+ if (!pll)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &clk_pll_ops;
+ init.flags = 0;
+ init.parent_names = (parent_name ? &parent_name : NULL);
+ init.num_parents = (parent_name ? 1 : 0);
+
+ pll->pll_data = pll_data;
+ pll->hw.init = &init;
+
+ clk = clk_register(NULL, &pll->hw);
+ if (IS_ERR(clk))
+ goto out;
+
+ return clk;
+out:
+ kfree(pll);
+ return NULL;
+}
+
+/**
+ * _of_clk_init - PLL initialisation via DT
+ * @node: device tree node for this clock
+ * @pllctrl: If true, lower 6 bits of multiplier is in pllm register of
+ * pll controller, else it is in the control regsiter0(bit 11-6)
+ */
+static void __init _of_pll_clk_init(struct device_node *node, bool pllctrl)
+{
+ struct clk_pll_data *pll_data;
+ const char *parent_name;
+ struct clk *clk;
+ int i;
+
+ pll_data = kzalloc(sizeof(*pll_data), GFP_KERNEL);
+ if (!pll_data) {
+ pr_err("%s: Out of memory\n", __func__);
+ return;
+ }
+
+ parent_name = of_clk_get_parent_name(node, 0);
+ if (of_property_read_u32(node, "fixed-postdiv", &pll_data->postdiv))
+ goto out;
+
+ i = of_property_match_string(node, "reg-names", "control");
+ pll_data->pll_ctl0 = of_iomap(node, i);
+ if (!pll_data->pll_ctl0) {
+ pr_err("%s: ioremap failed\n", __func__);
+ goto out;
+ }
+
+ pll_data->pllm_lower_mask = PLLM_LOW_MASK;
+ pll_data->pllm_upper_shift = PLLM_HIGH_SHIFT;
+ pll_data->plld_mask = PLLD_MASK;
+ pll_data->has_pllctrl = pllctrl;
+ if (!pll_data->has_pllctrl) {
+ pll_data->pllm_upper_mask = PLLM_HIGH_MASK;
+ } else {
+ pll_data->pllm_upper_mask = MAIN_PLLM_HIGH_MASK;
+ i = of_property_match_string(node, "reg-names", "multiplier");
+ pll_data->pllm = of_iomap(node, i);
+ if (!pll_data->pllm) {
+ iounmap(pll_data->pll_ctl0);
+ goto out;
+ }
+ }
+
+ clk = clk_register_pll(NULL, node->name, parent_name, pll_data);
+ if (clk) {
+ of_clk_add_provider(node, of_clk_src_simple_get, clk);
+ return;
+ }
+
+out:
+ pr_err("%s: error initializing pll %s\n", __func__, node->name);
+ kfree(pll_data);
+}
+
+/**
+ * of_keystone_pll_clk_init - PLL initialisation DT wrapper
+ * @node: device tree node for this clock
+ */
+static void __init of_keystone_pll_clk_init(struct device_node *node)
+{
+ _of_pll_clk_init(node, false);
+}
+CLK_OF_DECLARE(keystone_pll_clock, "ti,keystone,pll-clock",
+ of_keystone_pll_clk_init);
+
+/**
+ * of_keystone_pll_main_clk_init - Main PLL initialisation DT wrapper
+ * @node: device tree node for this clock
+ */
+static void __init of_keystone_main_pll_clk_init(struct device_node *node)
+{
+ _of_pll_clk_init(node, true);
+}
+CLK_OF_DECLARE(keystone_main_pll_clock, "ti,keystone,main-pll-clock",
+ of_keystone_main_pll_clk_init);
+
+/**
+ * of_pll_div_clk_init - PLL divider setup function
+ * @node: device tree node for this clock
+ */
+static void __init of_pll_div_clk_init(struct device_node *node)
+{
+ const char *parent_name;
+ void __iomem *reg;
+ u32 shift, mask;
+ struct clk *clk;
+ const char *clk_name = node->name;
+
+ of_property_read_string(node, "clock-output-names", &clk_name);
+ reg = of_iomap(node, 0);
+ if (!reg) {
+ pr_err("%s: ioremap failed\n", __func__);
+ return;
+ }
+
+ parent_name = of_clk_get_parent_name(node, 0);
+ if (!parent_name) {
+ pr_err("%s: missing parent clock\n", __func__);
+ return;
+ }
+
+ if (of_property_read_u32(node, "bit-shift", &shift)) {
+ pr_err("%s: missing 'shift' property\n", __func__);
+ return;
+ }
+
+ if (of_property_read_u32(node, "bit-mask", &mask)) {
+ pr_err("%s: missing 'bit-mask' property\n", __func__);
+ return;
+ }
+
+ clk = clk_register_divider(NULL, clk_name, parent_name, 0, reg, shift,
+ mask, 0, NULL);
+ if (clk)
+ of_clk_add_provider(node, of_clk_src_simple_get, clk);
+ else
+ pr_err("%s: error registering divider %s\n", __func__, clk_name);
+}
+CLK_OF_DECLARE(pll_divider_clock, "ti,keystone,pll-divider-clock", of_pll_div_clk_init);
+
+/**
+ * of_pll_mux_clk_init - PLL mux setup function
+ * @node: device tree node for this clock
+ */
+static void __init of_pll_mux_clk_init(struct device_node *node)
+{
+ void __iomem *reg;
+ u32 shift, mask;
+ struct clk *clk;
+ const char *parents[2];
+ const char *clk_name = node->name;
+
+ of_property_read_string(node, "clock-output-names", &clk_name);
+ reg = of_iomap(node, 0);
+ if (!reg) {
+ pr_err("%s: ioremap failed\n", __func__);
+ return;
+ }
+
+ parents[0] = of_clk_get_parent_name(node, 0);
+ parents[1] = of_clk_get_parent_name(node, 1);
+ if (!parents[0] || !parents[1]) {
+ pr_err("%s: missing parent clocks\n", __func__);
+ return;
+ }
+
+ if (of_property_read_u32(node, "bit-shift", &shift)) {
+ pr_err("%s: missing 'shift' property\n", __func__);
+ return;
+ }
+
+ if (of_property_read_u32(node, "bit-mask", &mask)) {
+ pr_err("%s: missing 'bit-mask' property\n", __func__);
+ return;
+ }
+
+ clk = clk_register_mux(NULL, clk_name, (const char **)&parents,
+ ARRAY_SIZE(parents) , 0, reg, shift, mask,
+ 0, NULL);
+ if (clk)
+ of_clk_add_provider(node, of_clk_src_simple_get, clk);
+ else
+ pr_err("%s: error registering mux %s\n", __func__, clk_name);
+}
+CLK_OF_DECLARE(pll_mux_clock, "ti,keystone,pll-mux-clock", of_pll_mux_clk_init);