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path: root/drivers/clk/clk-hsdk-pll.c
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-rw-r--r--drivers/clk/clk-hsdk-pll.c431
1 files changed, 431 insertions, 0 deletions
diff --git a/drivers/clk/clk-hsdk-pll.c b/drivers/clk/clk-hsdk-pll.c
new file mode 100644
index 0000000..bbf23717
--- /dev/null
+++ b/drivers/clk/clk-hsdk-pll.c
@@ -0,0 +1,431 @@
+/*
+ * Synopsys HSDK SDP Generic PLL clock driver
+ *
+ * Copyright (C) 2017 Synopsys
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#define CGU_PLL_CTRL 0x000 /* ARC PLL control register */
+#define CGU_PLL_STATUS 0x004 /* ARC PLL status register */
+#define CGU_PLL_FMEAS 0x008 /* ARC PLL frequency measurement register */
+#define CGU_PLL_MON 0x00C /* ARC PLL monitor register */
+
+#define CGU_PLL_CTRL_ODIV_SHIFT 2
+#define CGU_PLL_CTRL_IDIV_SHIFT 4
+#define CGU_PLL_CTRL_FBDIV_SHIFT 9
+#define CGU_PLL_CTRL_BAND_SHIFT 20
+
+#define CGU_PLL_CTRL_ODIV_MASK GENMASK(3, CGU_PLL_CTRL_ODIV_SHIFT)
+#define CGU_PLL_CTRL_IDIV_MASK GENMASK(8, CGU_PLL_CTRL_IDIV_SHIFT)
+#define CGU_PLL_CTRL_FBDIV_MASK GENMASK(15, CGU_PLL_CTRL_FBDIV_SHIFT)
+
+#define CGU_PLL_CTRL_PD BIT(0)
+#define CGU_PLL_CTRL_BYPASS BIT(1)
+
+#define CGU_PLL_STATUS_LOCK BIT(0)
+#define CGU_PLL_STATUS_ERR BIT(1)
+
+#define HSDK_PLL_MAX_LOCK_TIME 100 /* 100 us */
+
+#define CGU_PLL_SOURCE_MAX 1
+
+#define CORE_IF_CLK_THRESHOLD_HZ 500000000
+#define CREG_CORE_IF_CLK_DIV_1 0x0
+#define CREG_CORE_IF_CLK_DIV_2 0x1
+
+struct hsdk_pll_cfg {
+ u32 rate;
+ u32 idiv;
+ u32 fbdiv;
+ u32 odiv;
+ u32 band;
+};
+
+static const struct hsdk_pll_cfg asdt_pll_cfg[] = {
+ { 100000000, 0, 11, 3, 0 },
+ { 133000000, 0, 15, 3, 0 },
+ { 200000000, 1, 47, 3, 0 },
+ { 233000000, 1, 27, 2, 0 },
+ { 300000000, 1, 35, 2, 0 },
+ { 333000000, 1, 39, 2, 0 },
+ { 400000000, 1, 47, 2, 0 },
+ { 500000000, 0, 14, 1, 0 },
+ { 600000000, 0, 17, 1, 0 },
+ { 700000000, 0, 20, 1, 0 },
+ { 800000000, 0, 23, 1, 0 },
+ { 900000000, 1, 26, 0, 0 },
+ { 1000000000, 1, 29, 0, 0 },
+ { 1100000000, 1, 32, 0, 0 },
+ { 1200000000, 1, 35, 0, 0 },
+ { 1300000000, 1, 38, 0, 0 },
+ { 1400000000, 1, 41, 0, 0 },
+ { 1500000000, 1, 44, 0, 0 },
+ { 1600000000, 1, 47, 0, 0 },
+ {}
+};
+
+static const struct hsdk_pll_cfg hdmi_pll_cfg[] = {
+ { 297000000, 0, 21, 2, 0 },
+ { 540000000, 0, 19, 1, 0 },
+ { 594000000, 0, 21, 1, 0 },
+ {}
+};
+
+struct hsdk_pll_clk {
+ struct clk_hw hw;
+ void __iomem *regs;
+ void __iomem *spec_regs;
+ const struct hsdk_pll_devdata *pll_devdata;
+ struct device *dev;
+};
+
+struct hsdk_pll_devdata {
+ const struct hsdk_pll_cfg *pll_cfg;
+ int (*update_rate)(struct hsdk_pll_clk *clk, unsigned long rate,
+ const struct hsdk_pll_cfg *cfg);
+};
+
+static int hsdk_pll_core_update_rate(struct hsdk_pll_clk *, unsigned long,
+ const struct hsdk_pll_cfg *);
+static int hsdk_pll_comm_update_rate(struct hsdk_pll_clk *, unsigned long,
+ const struct hsdk_pll_cfg *);
+
+static const struct hsdk_pll_devdata core_pll_devdata = {
+ .pll_cfg = asdt_pll_cfg,
+ .update_rate = hsdk_pll_core_update_rate,
+};
+
+static const struct hsdk_pll_devdata sdt_pll_devdata = {
+ .pll_cfg = asdt_pll_cfg,
+ .update_rate = hsdk_pll_comm_update_rate,
+};
+
+static const struct hsdk_pll_devdata hdmi_pll_devdata = {
+ .pll_cfg = hdmi_pll_cfg,
+ .update_rate = hsdk_pll_comm_update_rate,
+};
+
+static inline void hsdk_pll_write(struct hsdk_pll_clk *clk, u32 reg, u32 val)
+{
+ iowrite32(val, clk->regs + reg);
+}
+
+static inline u32 hsdk_pll_read(struct hsdk_pll_clk *clk, u32 reg)
+{
+ return ioread32(clk->regs + reg);
+}
+
+static inline void hsdk_pll_set_cfg(struct hsdk_pll_clk *clk,
+ const struct hsdk_pll_cfg *cfg)
+{
+ u32 val = 0;
+
+ /* Powerdown and Bypass bits should be cleared */
+ val |= cfg->idiv << CGU_PLL_CTRL_IDIV_SHIFT;
+ val |= cfg->fbdiv << CGU_PLL_CTRL_FBDIV_SHIFT;
+ val |= cfg->odiv << CGU_PLL_CTRL_ODIV_SHIFT;
+ val |= cfg->band << CGU_PLL_CTRL_BAND_SHIFT;
+
+ dev_dbg(clk->dev, "write configurarion: %#x\n", val);
+
+ hsdk_pll_write(clk, CGU_PLL_CTRL, val);
+}
+
+static inline bool hsdk_pll_is_locked(struct hsdk_pll_clk *clk)
+{
+ return !!(hsdk_pll_read(clk, CGU_PLL_STATUS) & CGU_PLL_STATUS_LOCK);
+}
+
+static inline bool hsdk_pll_is_err(struct hsdk_pll_clk *clk)
+{
+ return !!(hsdk_pll_read(clk, CGU_PLL_STATUS) & CGU_PLL_STATUS_ERR);
+}
+
+static inline struct hsdk_pll_clk *to_hsdk_pll_clk(struct clk_hw *hw)
+{
+ return container_of(hw, struct hsdk_pll_clk, hw);
+}
+
+static unsigned long hsdk_pll_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ u32 val;
+ u64 rate;
+ u32 idiv, fbdiv, odiv;
+ struct hsdk_pll_clk *clk = to_hsdk_pll_clk(hw);
+
+ val = hsdk_pll_read(clk, CGU_PLL_CTRL);
+
+ dev_dbg(clk->dev, "current configurarion: %#x\n", val);
+
+ /* Check if PLL is disabled */
+ if (val & CGU_PLL_CTRL_PD)
+ return 0;
+
+ /* Check if PLL is bypassed */
+ if (val & CGU_PLL_CTRL_BYPASS)
+ return parent_rate;
+
+ /* input divider = reg.idiv + 1 */
+ idiv = 1 + ((val & CGU_PLL_CTRL_IDIV_MASK) >> CGU_PLL_CTRL_IDIV_SHIFT);
+ /* fb divider = 2*(reg.fbdiv + 1) */
+ fbdiv = 2 * (1 + ((val & CGU_PLL_CTRL_FBDIV_MASK) >> CGU_PLL_CTRL_FBDIV_SHIFT));
+ /* output divider = 2^(reg.odiv) */
+ odiv = 1 << ((val & CGU_PLL_CTRL_ODIV_MASK) >> CGU_PLL_CTRL_ODIV_SHIFT);
+
+ rate = (u64)parent_rate * fbdiv;
+ do_div(rate, idiv * odiv);
+
+ return rate;
+}
+
+static long hsdk_pll_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *prate)
+{
+ int i;
+ unsigned long best_rate;
+ struct hsdk_pll_clk *clk = to_hsdk_pll_clk(hw);
+ const struct hsdk_pll_cfg *pll_cfg = clk->pll_devdata->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;
+ }
+
+ dev_dbg(clk->dev, "chosen best rate: %lu\n", best_rate);
+
+ return best_rate;
+}
+
+static int hsdk_pll_comm_update_rate(struct hsdk_pll_clk *clk,
+ unsigned long rate,
+ const struct hsdk_pll_cfg *cfg)
+{
+ hsdk_pll_set_cfg(clk, cfg);
+
+ /*
+ * Wait until CGU relocks and check error status.
+ * If after timeout CGU is unlocked yet return error.
+ */
+ udelay(HSDK_PLL_MAX_LOCK_TIME);
+ if (!hsdk_pll_is_locked(clk))
+ return -ETIMEDOUT;
+
+ if (hsdk_pll_is_err(clk))
+ return -EINVAL;
+
+ return 0;
+}
+
+static int hsdk_pll_core_update_rate(struct hsdk_pll_clk *clk,
+ unsigned long rate,
+ const struct hsdk_pll_cfg *cfg)
+{
+ /*
+ * When core clock exceeds 500MHz, the divider for the interface
+ * clock must be programmed to div-by-2.
+ */
+ if (rate > CORE_IF_CLK_THRESHOLD_HZ)
+ iowrite32(CREG_CORE_IF_CLK_DIV_2, clk->spec_regs);
+
+ hsdk_pll_set_cfg(clk, cfg);
+
+ /*
+ * Wait until CGU relocks and check error status.
+ * If after timeout CGU is unlocked yet return error.
+ */
+ udelay(HSDK_PLL_MAX_LOCK_TIME);
+ if (!hsdk_pll_is_locked(clk))
+ return -ETIMEDOUT;
+
+ if (hsdk_pll_is_err(clk))
+ return -EINVAL;
+
+ /*
+ * Program divider to div-by-1 if we succesfuly set core clock below
+ * 500MHz threshold.
+ */
+ if (rate <= CORE_IF_CLK_THRESHOLD_HZ)
+ iowrite32(CREG_CORE_IF_CLK_DIV_1, clk->spec_regs);
+
+ return 0;
+}
+
+static int hsdk_pll_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ int i;
+ struct hsdk_pll_clk *clk = to_hsdk_pll_clk(hw);
+ const struct hsdk_pll_cfg *pll_cfg = clk->pll_devdata->pll_cfg;
+
+ for (i = 0; pll_cfg[i].rate != 0; i++) {
+ if (pll_cfg[i].rate == rate) {
+ return clk->pll_devdata->update_rate(clk, rate,
+ &pll_cfg[i]);
+ }
+ }
+
+ dev_err(clk->dev, "invalid rate=%ld, parent_rate=%ld\n", rate,
+ parent_rate);
+
+ return -EINVAL;
+}
+
+static const struct clk_ops hsdk_pll_ops = {
+ .recalc_rate = hsdk_pll_recalc_rate,
+ .round_rate = hsdk_pll_round_rate,
+ .set_rate = hsdk_pll_set_rate,
+};
+
+static int hsdk_pll_clk_probe(struct platform_device *pdev)
+{
+ int ret;
+ struct resource *mem;
+ const char *parent_name;
+ unsigned int num_parents;
+ struct hsdk_pll_clk *pll_clk;
+ struct clk_init_data init = { };
+ struct device *dev = &pdev->dev;
+
+ pll_clk = devm_kzalloc(dev, sizeof(*pll_clk), GFP_KERNEL);
+ if (!pll_clk)
+ return -ENOMEM;
+
+ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ pll_clk->regs = devm_ioremap_resource(dev, mem);
+ if (IS_ERR(pll_clk->regs))
+ return PTR_ERR(pll_clk->regs);
+
+ init.name = dev->of_node->name;
+ init.ops = &hsdk_pll_ops;
+ parent_name = of_clk_get_parent_name(dev->of_node, 0);
+ init.parent_names = &parent_name;
+ num_parents = of_clk_get_parent_count(dev->of_node);
+ if (num_parents == 0 || num_parents > CGU_PLL_SOURCE_MAX) {
+ dev_err(dev, "wrong clock parents number: %u\n", num_parents);
+ return -EINVAL;
+ }
+ init.num_parents = num_parents;
+
+ pll_clk->hw.init = &init;
+ pll_clk->dev = dev;
+ pll_clk->pll_devdata = of_device_get_match_data(dev);
+
+ if (!pll_clk->pll_devdata) {
+ 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 hsdk_pll_clk_remove(struct platform_device *pdev)
+{
+ of_clk_del_provider(pdev->dev.of_node);
+ return 0;
+}
+
+static void __init of_hsdk_pll_clk_setup(struct device_node *node)
+{
+ int ret;
+ const char *parent_name;
+ unsigned int num_parents;
+ struct hsdk_pll_clk *pll_clk;
+ struct clk_init_data init = { };
+
+ pll_clk = kzalloc(sizeof(*pll_clk), GFP_KERNEL);
+ if (!pll_clk)
+ return;
+
+ pll_clk->regs = of_iomap(node, 0);
+ if (!pll_clk->regs) {
+ pr_err("failed to map pll registers\n");
+ goto err_free_pll_clk;
+ }
+
+ pll_clk->spec_regs = of_iomap(node, 1);
+ if (!pll_clk->spec_regs) {
+ pr_err("failed to map pll registers\n");
+ goto err_unmap_comm_regs;
+ }
+
+ init.name = node->name;
+ init.ops = &hsdk_pll_ops;
+ parent_name = of_clk_get_parent_name(node, 0);
+ init.parent_names = &parent_name;
+ num_parents = of_clk_get_parent_count(node);
+ if (num_parents > CGU_PLL_SOURCE_MAX) {
+ pr_err("too much clock parents: %u\n", num_parents);
+ goto err_unmap_spec_regs;
+ }
+ init.num_parents = num_parents;
+
+ pll_clk->hw.init = &init;
+ pll_clk->pll_devdata = &core_pll_devdata;
+
+ ret = clk_hw_register(NULL, &pll_clk->hw);
+ if (ret) {
+ pr_err("failed to register %s clock\n", node->name);
+ goto err_unmap_spec_regs;
+ }
+
+ 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 %s clock\n", node->name);
+ goto err_unmap_spec_regs;
+ }
+
+ return;
+
+err_unmap_spec_regs:
+ iounmap(pll_clk->spec_regs);
+err_unmap_comm_regs:
+ iounmap(pll_clk->regs);
+err_free_pll_clk:
+ kfree(pll_clk);
+}
+
+/* Core PLL needed early for ARC cpus timers */
+CLK_OF_DECLARE(hsdk_pll_clock, "snps,hsdk-core-pll-clock",
+of_hsdk_pll_clk_setup);
+
+static const struct of_device_id hsdk_pll_clk_id[] = {
+ { .compatible = "snps,hsdk-gp-pll-clock", .data = &sdt_pll_devdata},
+ { .compatible = "snps,hsdk-hdmi-pll-clock", .data = &hdmi_pll_devdata},
+ { }
+};
+
+static struct platform_driver hsdk_pll_clk_driver = {
+ .driver = {
+ .name = "hsdk-gp-pll-clock",
+ .of_match_table = hsdk_pll_clk_id,
+ },
+ .probe = hsdk_pll_clk_probe,
+ .remove = hsdk_pll_clk_remove,
+};
+builtin_platform_driver(hsdk_pll_clk_driver);
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