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path: root/drivers/clk/axs10x/pll_clock.c
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Diffstat (limited to 'drivers/clk/axs10x/pll_clock.c')
-rw-r--r--drivers/clk/axs10x/pll_clock.c341
1 files changed, 341 insertions, 0 deletions
diff --git a/drivers/clk/axs10x/pll_clock.c b/drivers/clk/axs10x/pll_clock.c
new file mode 100644
index 000000000..90fb0e6ff
--- /dev/null
+++ b/drivers/clk/axs10x/pll_clock.c
@@ -0,0 +1,341 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Synopsys AXS10X SDP Generic PLL clock driver
+ *
+ * Copyright (C) 2017 Synopsys
+ */
+
+#include <linux/platform_device.h>
+#include <linux/module.h>
+#include <linux/clk-provider.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+
+/* PLL registers addresses */
+#define PLL_REG_IDIV 0x0
+#define PLL_REG_FBDIV 0x4
+#define PLL_REG_ODIV 0x8
+
+/*
+ * Bit fields of the PLL IDIV/FBDIV/ODIV registers:
+ * ________________________________________________________________________
+ * |31 15| 14 | 13 | 12 |11 6|5 0|
+ * |-------RESRVED------|-NOUPDATE-|-BYPASS-|-EDGE-|--HIGHTIME--|--LOWTIME--|
+ * |____________________|__________|________|______|____________|___________|
+ *
+ * Following macros determine the way of access to these registers
+ * They should be set up only using the macros.
+ * reg should be an u32 variable.
+ */
+
+#define PLL_REG_GET_LOW(reg) \
+ (((reg) & (0x3F << 0)) >> 0)
+#define PLL_REG_GET_HIGH(reg) \
+ (((reg) & (0x3F << 6)) >> 6)
+#define PLL_REG_GET_EDGE(reg) \
+ (((reg) & (BIT(12))) ? 1 : 0)
+#define PLL_REG_GET_BYPASS(reg) \
+ (((reg) & (BIT(13))) ? 1 : 0)
+#define PLL_REG_GET_NOUPD(reg) \
+ (((reg) & (BIT(14))) ? 1 : 0)
+#define PLL_REG_GET_PAD(reg) \
+ (((reg) & (0x1FFFF << 15)) >> 15)
+
+#define PLL_REG_SET_LOW(reg, value) \
+ { reg |= (((value) & 0x3F) << 0); }
+#define PLL_REG_SET_HIGH(reg, value) \
+ { reg |= (((value) & 0x3F) << 6); }
+#define PLL_REG_SET_EDGE(reg, value) \
+ { reg |= (((value) & 0x01) << 12); }
+#define PLL_REG_SET_BYPASS(reg, value) \
+ { reg |= (((value) & 0x01) << 13); }
+#define PLL_REG_SET_NOUPD(reg, value) \
+ { reg |= (((value) & 0x01) << 14); }
+#define PLL_REG_SET_PAD(reg, value) \
+ { reg |= (((value) & 0x1FFFF) << 15); }
+
+#define PLL_LOCK BIT(0)
+#define PLL_ERROR BIT(1)
+#define PLL_MAX_LOCK_TIME 100 /* 100 us */
+
+struct axs10x_pll_cfg {
+ u32 rate;
+ u32 idiv;
+ u32 fbdiv;
+ u32 odiv;
+};
+
+static const struct axs10x_pll_cfg arc_pll_cfg[] = {
+ { 33333333, 1, 1, 1 },
+ { 50000000, 1, 30, 20 },
+ { 75000000, 2, 45, 10 },
+ { 90000000, 2, 54, 10 },
+ { 100000000, 1, 30, 10 },
+ { 125000000, 2, 45, 6 },
+ {}
+};
+
+static const struct axs10x_pll_cfg pgu_pll_cfg[] = {
+ { 25200000, 1, 84, 90 },
+ { 50000000, 1, 100, 54 },
+ { 74250000, 1, 44, 16 },
+ {}
+};
+
+struct axs10x_pll_clk {
+ struct clk_hw hw;
+ void __iomem *base;
+ void __iomem *lock;
+ const struct axs10x_pll_cfg *pll_cfg;
+ struct device *dev;
+};
+
+static inline void axs10x_pll_write(struct axs10x_pll_clk *clk, u32 reg,
+ u32 val)
+{
+ iowrite32(val, clk->base + reg);
+}
+
+static inline u32 axs10x_pll_read(struct axs10x_pll_clk *clk, u32 reg)
+{
+ return ioread32(clk->base + reg);
+}
+
+static inline struct axs10x_pll_clk *to_axs10x_pll_clk(struct clk_hw *hw)
+{
+ return container_of(hw, struct axs10x_pll_clk, hw);
+}
+
+static inline u32 axs10x_div_get_value(u32 reg)
+{
+ if (PLL_REG_GET_BYPASS(reg))
+ return 1;
+
+ return PLL_REG_GET_HIGH(reg) + PLL_REG_GET_LOW(reg);
+}
+
+static inline u32 axs10x_encode_div(unsigned int id, int upd)
+{
+ u32 div = 0;
+
+ PLL_REG_SET_LOW(div, (id % 2 == 0) ? id >> 1 : (id >> 1) + 1);
+ PLL_REG_SET_HIGH(div, id >> 1);
+ PLL_REG_SET_EDGE(div, id % 2);
+ PLL_REG_SET_BYPASS(div, id == 1 ? 1 : 0);
+ PLL_REG_SET_NOUPD(div, upd == 0 ? 1 : 0);
+
+ return div;
+}
+
+static unsigned long axs10x_pll_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ u64 rate;
+ u32 idiv, fbdiv, odiv;
+ struct axs10x_pll_clk *clk = to_axs10x_pll_clk(hw);
+
+ idiv = axs10x_div_get_value(axs10x_pll_read(clk, PLL_REG_IDIV));
+ fbdiv = axs10x_div_get_value(axs10x_pll_read(clk, PLL_REG_FBDIV));
+ odiv = axs10x_div_get_value(axs10x_pll_read(clk, PLL_REG_ODIV));
+
+ rate = (u64)parent_rate * fbdiv;
+ do_div(rate, idiv * odiv);
+
+ return rate;
+}
+
+static long axs10x_pll_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *prate)
+{
+ int i;
+ long best_rate;
+ struct axs10x_pll_clk *clk = to_axs10x_pll_clk(hw);
+ const struct axs10x_pll_cfg *pll_cfg = clk->pll_cfg;
+
+ if (pll_cfg[0].rate == 0)
+ return -EINVAL;
+
+ best_rate = pll_cfg[0].rate;
+
+ for (i = 1; pll_cfg[i].rate != 0; i++) {
+ if (abs(rate - pll_cfg[i].rate) < abs(rate - best_rate))
+ best_rate = pll_cfg[i].rate;
+ }
+
+ return best_rate;
+}
+
+static int axs10x_pll_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ int i;
+ struct axs10x_pll_clk *clk = to_axs10x_pll_clk(hw);
+ const struct axs10x_pll_cfg *pll_cfg = clk->pll_cfg;
+
+ for (i = 0; pll_cfg[i].rate != 0; i++) {
+ if (pll_cfg[i].rate == rate) {
+ axs10x_pll_write(clk, PLL_REG_IDIV,
+ axs10x_encode_div(pll_cfg[i].idiv, 0));
+ axs10x_pll_write(clk, PLL_REG_FBDIV,
+ axs10x_encode_div(pll_cfg[i].fbdiv, 0));
+ axs10x_pll_write(clk, PLL_REG_ODIV,
+ axs10x_encode_div(pll_cfg[i].odiv, 1));
+
+ /*
+ * Wait until CGU relocks and check error status.
+ * If after timeout CGU is unlocked yet return error
+ */
+ udelay(PLL_MAX_LOCK_TIME);
+ if (!(ioread32(clk->lock) & PLL_LOCK))
+ return -ETIMEDOUT;
+
+ if (ioread32(clk->lock) & PLL_ERROR)
+ return -EINVAL;
+
+ return 0;
+ }
+ }
+
+ dev_err(clk->dev, "invalid rate=%ld, parent_rate=%ld\n", rate,
+ parent_rate);
+ return -EINVAL;
+}
+
+static const struct clk_ops axs10x_pll_ops = {
+ .recalc_rate = axs10x_pll_recalc_rate,
+ .round_rate = axs10x_pll_round_rate,
+ .set_rate = axs10x_pll_set_rate,
+};
+
+static int axs10x_pll_clk_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ const char *parent_name;
+ struct axs10x_pll_clk *pll_clk;
+ struct clk_init_data init = { };
+ int ret;
+
+ pll_clk = devm_kzalloc(dev, sizeof(*pll_clk), GFP_KERNEL);
+ if (!pll_clk)
+ return -ENOMEM;
+
+ pll_clk->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(pll_clk->base))
+ return PTR_ERR(pll_clk->base);
+
+ pll_clk->lock = devm_platform_ioremap_resource(pdev, 1);
+ if (IS_ERR(pll_clk->lock))
+ return PTR_ERR(pll_clk->lock);
+
+ init.name = dev->of_node->name;
+ init.ops = &axs10x_pll_ops;
+ parent_name = of_clk_get_parent_name(dev->of_node, 0);
+ init.parent_names = &parent_name;
+ init.num_parents = 1;
+ pll_clk->hw.init = &init;
+ pll_clk->dev = dev;
+ pll_clk->pll_cfg = of_device_get_match_data(dev);
+
+ if (!pll_clk->pll_cfg) {
+ dev_err(dev, "No OF match data provided\n");
+ return -EINVAL;
+ }
+
+ ret = devm_clk_hw_register(dev, &pll_clk->hw);
+ if (ret) {
+ dev_err(dev, "failed to register %s clock\n", init.name);
+ return ret;
+ }
+
+ return of_clk_add_hw_provider(dev->of_node, of_clk_hw_simple_get,
+ &pll_clk->hw);
+}
+
+static int axs10x_pll_clk_remove(struct platform_device *pdev)
+{
+ of_clk_del_provider(pdev->dev.of_node);
+ return 0;
+}
+
+static void __init of_axs10x_pll_clk_setup(struct device_node *node)
+{
+ const char *parent_name;
+ struct axs10x_pll_clk *pll_clk;
+ struct clk_init_data init = { };
+ int ret;
+
+ pll_clk = kzalloc(sizeof(*pll_clk), GFP_KERNEL);
+ if (!pll_clk)
+ return;
+
+ pll_clk->base = of_iomap(node, 0);
+ if (!pll_clk->base) {
+ pr_err("failed to map pll div registers\n");
+ goto err_free_pll_clk;
+ }
+
+ pll_clk->lock = of_iomap(node, 1);
+ if (!pll_clk->lock) {
+ pr_err("failed to map pll lock register\n");
+ goto err_unmap_base;
+ }
+
+ init.name = node->name;
+ init.ops = &axs10x_pll_ops;
+ parent_name = of_clk_get_parent_name(node, 0);
+ init.parent_names = &parent_name;
+ init.num_parents = parent_name ? 1 : 0;
+ pll_clk->hw.init = &init;
+ pll_clk->pll_cfg = arc_pll_cfg;
+
+ ret = clk_hw_register(NULL, &pll_clk->hw);
+ if (ret) {
+ pr_err("failed to register %pOFn clock\n", node);
+ goto err_unmap_lock;
+ }
+
+ ret = of_clk_add_hw_provider(node, of_clk_hw_simple_get, &pll_clk->hw);
+ if (ret) {
+ pr_err("failed to add hw provider for %pOFn clock\n", node);
+ goto err_unregister_clk;
+ }
+
+ return;
+
+err_unregister_clk:
+ clk_hw_unregister(&pll_clk->hw);
+err_unmap_lock:
+ iounmap(pll_clk->lock);
+err_unmap_base:
+ iounmap(pll_clk->base);
+err_free_pll_clk:
+ kfree(pll_clk);
+}
+CLK_OF_DECLARE(axs10x_pll_clock, "snps,axs10x-arc-pll-clock",
+ of_axs10x_pll_clk_setup);
+
+static const struct of_device_id axs10x_pll_clk_id[] = {
+ { .compatible = "snps,axs10x-pgu-pll-clock", .data = &pgu_pll_cfg},
+ { }
+};
+MODULE_DEVICE_TABLE(of, axs10x_pll_clk_id);
+
+static struct platform_driver axs10x_pll_clk_driver = {
+ .driver = {
+ .name = "axs10x-pll-clock",
+ .of_match_table = axs10x_pll_clk_id,
+ },
+ .probe = axs10x_pll_clk_probe,
+ .remove = axs10x_pll_clk_remove,
+};
+builtin_platform_driver(axs10x_pll_clk_driver);
+
+MODULE_AUTHOR("Vlad Zakharov <vzakhar@synopsys.com>");
+MODULE_DESCRIPTION("Synopsys AXS10X SDP Generic PLL Clock Driver");
+MODULE_LICENSE("GPL v2");