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path: root/drivers/clk/imx/clk-pllv4.c
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Diffstat (limited to 'drivers/clk/imx/clk-pllv4.c')
-rw-r--r--drivers/clk/imx/clk-pllv4.c184
1 files changed, 184 insertions, 0 deletions
diff --git a/drivers/clk/imx/clk-pllv4.c b/drivers/clk/imx/clk-pllv4.c
new file mode 100644
index 000000000000..d38bc9f87c1d
--- /dev/null
+++ b/drivers/clk/imx/clk-pllv4.c
@@ -0,0 +1,184 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2016 Freescale Semiconductor, Inc.
+ * Copyright 2017~2018 NXP
+ *
+ * Author: Dong Aisheng <aisheng.dong@nxp.com>
+ *
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/err.h>
+#include <linux/iopoll.h>
+#include <linux/slab.h>
+
+#include "clk.h"
+
+/* PLL Control Status Register (xPLLCSR) */
+#define PLL_CSR_OFFSET 0x0
+#define PLL_VLD BIT(24)
+#define PLL_EN BIT(0)
+
+/* PLL Configuration Register (xPLLCFG) */
+#define PLL_CFG_OFFSET 0x08
+#define BP_PLL_MULT 16
+#define BM_PLL_MULT (0x7f << 16)
+
+/* PLL Numerator Register (xPLLNUM) */
+#define PLL_NUM_OFFSET 0x10
+
+/* PLL Denominator Register (xPLLDENOM) */
+#define PLL_DENOM_OFFSET 0x14
+
+struct clk_pllv4 {
+ struct clk_hw hw;
+ void __iomem *base;
+};
+
+/* Valid PLL MULT Table */
+static const int pllv4_mult_table[] = {33, 27, 22, 20, 17, 16};
+
+#define to_clk_pllv4(__hw) container_of(__hw, struct clk_pllv4, hw)
+
+#define LOCK_TIMEOUT_US USEC_PER_MSEC
+
+static inline int clk_pllv4_wait_lock(struct clk_pllv4 *pll)
+{
+ u32 csr;
+
+ return readl_poll_timeout(pll->base + PLL_CSR_OFFSET,
+ csr, csr & PLL_VLD, 0, LOCK_TIMEOUT_US);
+}
+
+static int clk_pllv4_is_enabled(struct clk_hw *hw)
+{
+ struct clk_pllv4 *pll = to_clk_pllv4(hw);
+
+ if (readl_relaxed(pll->base) & PLL_EN)
+ return 1;
+
+ return 0;
+}
+
+static unsigned long clk_pllv4_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_pllv4 *pll = to_clk_pllv4(hw);
+ u32 div;
+
+ div = readl_relaxed(pll->base + PLL_CFG_OFFSET);
+ div &= BM_PLL_MULT;
+ div >>= BP_PLL_MULT;
+
+ return parent_rate * div;
+}
+
+static long clk_pllv4_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *prate)
+{
+ unsigned long parent_rate = *prate;
+ unsigned long round_rate, i;
+
+ for (i = 0; i < ARRAY_SIZE(pllv4_mult_table); i++) {
+ round_rate = parent_rate * pllv4_mult_table[i];
+ if (rate >= round_rate)
+ return round_rate;
+ }
+
+ return round_rate;
+}
+
+static bool clk_pllv4_is_valid_mult(unsigned int mult)
+{
+ int i;
+
+ /* check if mult is in valid MULT table */
+ for (i = 0; i < ARRAY_SIZE(pllv4_mult_table); i++) {
+ if (pllv4_mult_table[i] == mult)
+ return true;
+ }
+
+ return false;
+}
+
+static int clk_pllv4_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct clk_pllv4 *pll = to_clk_pllv4(hw);
+ u32 val, mult;
+
+ mult = rate / parent_rate;
+
+ if (!clk_pllv4_is_valid_mult(mult))
+ return -EINVAL;
+
+ val = readl_relaxed(pll->base + PLL_CFG_OFFSET);
+ val &= ~BM_PLL_MULT;
+ val |= mult << BP_PLL_MULT;
+ writel_relaxed(val, pll->base + PLL_CFG_OFFSET);
+
+ return 0;
+}
+
+static int clk_pllv4_enable(struct clk_hw *hw)
+{
+ u32 val;
+ struct clk_pllv4 *pll = to_clk_pllv4(hw);
+
+ val = readl_relaxed(pll->base);
+ val |= PLL_EN;
+ writel_relaxed(val, pll->base);
+
+ return clk_pllv4_wait_lock(pll);
+}
+
+static void clk_pllv4_disable(struct clk_hw *hw)
+{
+ u32 val;
+ struct clk_pllv4 *pll = to_clk_pllv4(hw);
+
+ val = readl_relaxed(pll->base);
+ val &= ~PLL_EN;
+ writel_relaxed(val, pll->base);
+}
+
+static const struct clk_ops clk_pllv4_ops = {
+ .recalc_rate = clk_pllv4_recalc_rate,
+ .round_rate = clk_pllv4_round_rate,
+ .set_rate = clk_pllv4_set_rate,
+ .enable = clk_pllv4_enable,
+ .disable = clk_pllv4_disable,
+ .is_enabled = clk_pllv4_is_enabled,
+};
+
+struct clk_hw *imx_clk_pllv4(const char *name, const char *parent_name,
+ void __iomem *base)
+{
+ struct clk_pllv4 *pll;
+ struct clk_hw *hw;
+ struct clk_init_data init;
+ int ret;
+
+ pll = kzalloc(sizeof(*pll), GFP_KERNEL);
+ if (!pll)
+ return ERR_PTR(-ENOMEM);
+
+ pll->base = base;
+
+ init.name = name;
+ init.ops = &clk_pllv4_ops;
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+ init.flags = CLK_SET_RATE_GATE;
+
+ pll->hw.init = &init;
+
+ hw = &pll->hw;
+ ret = clk_hw_register(NULL, hw);
+ if (ret) {
+ kfree(pll);
+ hw = ERR_PTR(ret);
+ }
+
+ return hw;
+}