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-rw-r--r--drivers/clk/sunxi/clk-mod0.c374
1 files changed, 374 insertions, 0 deletions
diff --git a/drivers/clk/sunxi/clk-mod0.c b/drivers/clk/sunxi/clk-mod0.c
new file mode 100644
index 000000000..51800289a
--- /dev/null
+++ b/drivers/clk/sunxi/clk-mod0.c
@@ -0,0 +1,374 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright 2013 Emilio López
+ *
+ * Emilio López <emilio@elopez.com.ar>
+ */
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#include "clk-factors.h"
+
+/*
+ * sun4i_a10_get_mod0_factors() - calculates m, n factors for MOD0-style clocks
+ * MOD0 rate is calculated as follows
+ * rate = (parent_rate >> p) / (m + 1);
+ */
+
+static void sun4i_a10_get_mod0_factors(struct factors_request *req)
+{
+ u8 div, calcm, calcp;
+
+ /* These clocks can only divide, so we will never be able to achieve
+ * frequencies higher than the parent frequency */
+ if (req->rate > req->parent_rate)
+ req->rate = req->parent_rate;
+
+ div = DIV_ROUND_UP(req->parent_rate, req->rate);
+
+ if (div < 16)
+ calcp = 0;
+ else if (div / 2 < 16)
+ calcp = 1;
+ else if (div / 4 < 16)
+ calcp = 2;
+ else
+ calcp = 3;
+
+ calcm = DIV_ROUND_UP(div, 1 << calcp);
+
+ req->rate = (req->parent_rate >> calcp) / calcm;
+ req->m = calcm - 1;
+ req->p = calcp;
+}
+
+/* user manual says "n" but it's really "p" */
+static const struct clk_factors_config sun4i_a10_mod0_config = {
+ .mshift = 0,
+ .mwidth = 4,
+ .pshift = 16,
+ .pwidth = 2,
+};
+
+static const struct factors_data sun4i_a10_mod0_data = {
+ .enable = 31,
+ .mux = 24,
+ .muxmask = BIT(1) | BIT(0),
+ .table = &sun4i_a10_mod0_config,
+ .getter = sun4i_a10_get_mod0_factors,
+};
+
+static DEFINE_SPINLOCK(sun4i_a10_mod0_lock);
+
+static void __init sun4i_a10_mod0_setup(struct device_node *node)
+{
+ void __iomem *reg;
+
+ reg = of_iomap(node, 0);
+ if (!reg) {
+ /*
+ * This happens with mod0 clk nodes instantiated through
+ * mfd, as those do not have their resources assigned at
+ * CLK_OF_DECLARE time yet, so do not print an error.
+ */
+ return;
+ }
+
+ sunxi_factors_register(node, &sun4i_a10_mod0_data,
+ &sun4i_a10_mod0_lock, reg);
+}
+CLK_OF_DECLARE_DRIVER(sun4i_a10_mod0, "allwinner,sun4i-a10-mod0-clk",
+ sun4i_a10_mod0_setup);
+
+static int sun4i_a10_mod0_clk_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ void __iomem *reg;
+
+ if (!np)
+ return -ENODEV;
+
+ reg = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(reg))
+ return PTR_ERR(reg);
+
+ sunxi_factors_register(np, &sun4i_a10_mod0_data,
+ &sun4i_a10_mod0_lock, reg);
+ return 0;
+}
+
+static const struct of_device_id sun4i_a10_mod0_clk_dt_ids[] = {
+ { .compatible = "allwinner,sun4i-a10-mod0-clk" },
+ { /* sentinel */ }
+};
+
+static struct platform_driver sun4i_a10_mod0_clk_driver = {
+ .driver = {
+ .name = "sun4i-a10-mod0-clk",
+ .of_match_table = sun4i_a10_mod0_clk_dt_ids,
+ },
+ .probe = sun4i_a10_mod0_clk_probe,
+};
+builtin_platform_driver(sun4i_a10_mod0_clk_driver);
+
+static const struct factors_data sun9i_a80_mod0_data __initconst = {
+ .enable = 31,
+ .mux = 24,
+ .muxmask = BIT(3) | BIT(2) | BIT(1) | BIT(0),
+ .table = &sun4i_a10_mod0_config,
+ .getter = sun4i_a10_get_mod0_factors,
+};
+
+static void __init sun9i_a80_mod0_setup(struct device_node *node)
+{
+ void __iomem *reg;
+
+ reg = of_io_request_and_map(node, 0, of_node_full_name(node));
+ if (IS_ERR(reg)) {
+ pr_err("Could not get registers for mod0-clk: %pOFn\n",
+ node);
+ return;
+ }
+
+ sunxi_factors_register(node, &sun9i_a80_mod0_data,
+ &sun4i_a10_mod0_lock, reg);
+}
+CLK_OF_DECLARE(sun9i_a80_mod0, "allwinner,sun9i-a80-mod0-clk", sun9i_a80_mod0_setup);
+
+static DEFINE_SPINLOCK(sun5i_a13_mbus_lock);
+
+static void __init sun5i_a13_mbus_setup(struct device_node *node)
+{
+ void __iomem *reg;
+
+ reg = of_iomap(node, 0);
+ if (!reg) {
+ pr_err("Could not get registers for a13-mbus-clk\n");
+ return;
+ }
+
+ /* The MBUS clocks needs to be always enabled */
+ sunxi_factors_register_critical(node, &sun4i_a10_mod0_data,
+ &sun5i_a13_mbus_lock, reg);
+}
+CLK_OF_DECLARE(sun5i_a13_mbus, "allwinner,sun5i-a13-mbus-clk", sun5i_a13_mbus_setup);
+
+struct mmc_phase {
+ struct clk_hw hw;
+ u8 offset;
+ void __iomem *reg;
+ spinlock_t *lock;
+};
+
+#define to_mmc_phase(_hw) container_of(_hw, struct mmc_phase, hw)
+
+static int mmc_get_phase(struct clk_hw *hw)
+{
+ struct clk *mmc, *mmc_parent, *clk = hw->clk;
+ struct mmc_phase *phase = to_mmc_phase(hw);
+ unsigned int mmc_rate, mmc_parent_rate;
+ u16 step, mmc_div;
+ u32 value;
+ u8 delay;
+
+ value = readl(phase->reg);
+ delay = (value >> phase->offset) & 0x3;
+
+ if (!delay)
+ return 180;
+
+ /* Get the main MMC clock */
+ mmc = clk_get_parent(clk);
+ if (!mmc)
+ return -EINVAL;
+
+ /* And its rate */
+ mmc_rate = clk_get_rate(mmc);
+ if (!mmc_rate)
+ return -EINVAL;
+
+ /* Now, get the MMC parent (most likely some PLL) */
+ mmc_parent = clk_get_parent(mmc);
+ if (!mmc_parent)
+ return -EINVAL;
+
+ /* And its rate */
+ mmc_parent_rate = clk_get_rate(mmc_parent);
+ if (!mmc_parent_rate)
+ return -EINVAL;
+
+ /* Get MMC clock divider */
+ mmc_div = mmc_parent_rate / mmc_rate;
+
+ step = DIV_ROUND_CLOSEST(360, mmc_div);
+ return delay * step;
+}
+
+static int mmc_set_phase(struct clk_hw *hw, int degrees)
+{
+ struct clk *mmc, *mmc_parent, *clk = hw->clk;
+ struct mmc_phase *phase = to_mmc_phase(hw);
+ unsigned int mmc_rate, mmc_parent_rate;
+ unsigned long flags;
+ u32 value;
+ u8 delay;
+
+ /* Get the main MMC clock */
+ mmc = clk_get_parent(clk);
+ if (!mmc)
+ return -EINVAL;
+
+ /* And its rate */
+ mmc_rate = clk_get_rate(mmc);
+ if (!mmc_rate)
+ return -EINVAL;
+
+ /* Now, get the MMC parent (most likely some PLL) */
+ mmc_parent = clk_get_parent(mmc);
+ if (!mmc_parent)
+ return -EINVAL;
+
+ /* And its rate */
+ mmc_parent_rate = clk_get_rate(mmc_parent);
+ if (!mmc_parent_rate)
+ return -EINVAL;
+
+ if (degrees != 180) {
+ u16 step, mmc_div;
+
+ /* Get MMC clock divider */
+ mmc_div = mmc_parent_rate / mmc_rate;
+
+ /*
+ * We can only outphase the clocks by multiple of the
+ * PLL's period.
+ *
+ * Since the MMC clock in only a divider, and the
+ * formula to get the outphasing in degrees is deg =
+ * 360 * delta / period
+ *
+ * If we simplify this formula, we can see that the
+ * only thing that we're concerned about is the number
+ * of period we want to outphase our clock from, and
+ * the divider set by the MMC clock.
+ */
+ step = DIV_ROUND_CLOSEST(360, mmc_div);
+ delay = DIV_ROUND_CLOSEST(degrees, step);
+ } else {
+ delay = 0;
+ }
+
+ spin_lock_irqsave(phase->lock, flags);
+ value = readl(phase->reg);
+ value &= ~GENMASK(phase->offset + 3, phase->offset);
+ value |= delay << phase->offset;
+ writel(value, phase->reg);
+ spin_unlock_irqrestore(phase->lock, flags);
+
+ return 0;
+}
+
+static const struct clk_ops mmc_clk_ops = {
+ .get_phase = mmc_get_phase,
+ .set_phase = mmc_set_phase,
+};
+
+/*
+ * sunxi_mmc_setup - Common setup function for mmc module clocks
+ *
+ * The only difference between module clocks on different platforms is the
+ * width of the mux register bits and the valid values, which are passed in
+ * through struct factors_data. The phase clocks parts are identical.
+ */
+static void __init sunxi_mmc_setup(struct device_node *node,
+ const struct factors_data *data,
+ spinlock_t *lock)
+{
+ struct clk_onecell_data *clk_data;
+ const char *parent;
+ void __iomem *reg;
+ int i;
+
+ reg = of_io_request_and_map(node, 0, of_node_full_name(node));
+ if (IS_ERR(reg)) {
+ pr_err("Couldn't map the %pOFn clock registers\n", node);
+ return;
+ }
+
+ clk_data = kmalloc(sizeof(*clk_data), GFP_KERNEL);
+ if (!clk_data)
+ return;
+
+ clk_data->clks = kcalloc(3, sizeof(*clk_data->clks), GFP_KERNEL);
+ if (!clk_data->clks)
+ goto err_free_data;
+
+ clk_data->clk_num = 3;
+ clk_data->clks[0] = sunxi_factors_register(node, data, lock, reg);
+ if (!clk_data->clks[0])
+ goto err_free_clks;
+
+ parent = __clk_get_name(clk_data->clks[0]);
+
+ for (i = 1; i < 3; i++) {
+ struct clk_init_data init = {
+ .num_parents = 1,
+ .parent_names = &parent,
+ .ops = &mmc_clk_ops,
+ };
+ struct mmc_phase *phase;
+
+ phase = kmalloc(sizeof(*phase), GFP_KERNEL);
+ if (!phase)
+ continue;
+
+ phase->hw.init = &init;
+ phase->reg = reg;
+ phase->lock = lock;
+
+ if (i == 1)
+ phase->offset = 8;
+ else
+ phase->offset = 20;
+
+ if (of_property_read_string_index(node, "clock-output-names",
+ i, &init.name))
+ init.name = node->name;
+
+ clk_data->clks[i] = clk_register(NULL, &phase->hw);
+ if (IS_ERR(clk_data->clks[i])) {
+ kfree(phase);
+ continue;
+ }
+ }
+
+ of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
+
+ return;
+
+err_free_clks:
+ kfree(clk_data->clks);
+err_free_data:
+ kfree(clk_data);
+}
+
+static DEFINE_SPINLOCK(sun4i_a10_mmc_lock);
+
+static void __init sun4i_a10_mmc_setup(struct device_node *node)
+{
+ sunxi_mmc_setup(node, &sun4i_a10_mod0_data, &sun4i_a10_mmc_lock);
+}
+CLK_OF_DECLARE(sun4i_a10_mmc, "allwinner,sun4i-a10-mmc-clk", sun4i_a10_mmc_setup);
+
+static DEFINE_SPINLOCK(sun9i_a80_mmc_lock);
+
+static void __init sun9i_a80_mmc_setup(struct device_node *node)
+{
+ sunxi_mmc_setup(node, &sun9i_a80_mod0_data, &sun9i_a80_mmc_lock);
+}
+CLK_OF_DECLARE(sun9i_a80_mmc, "allwinner,sun9i-a80-mmc-clk", sun9i_a80_mmc_setup);