--- /dev/null
+/*
+ * SCI Clock driver for keystone based devices
+ *
+ * Copyright (C) 2015-2016 Texas Instruments Incorporated - http://www.ti.com/
+ * Tero Kristo <t-kristo@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+#include <linux/clk-provider.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/soc/ti/ti_sci_protocol.h>
+
+#define SCI_CLK_SSC_ENABLE BIT(0)
+#define SCI_CLK_ALLOW_FREQ_CHANGE BIT(1)
+#define SCI_CLK_INPUT_TERMINATION BIT(2)
+
+/**
+ * struct sci_clk_data - TI SCI clock data
+ * @dev: device index
+ * @num_clks: number of clocks for this device
+ */
+struct sci_clk_data {
+ u16 dev;
+ u16 num_clks;
+};
+
+/**
+ * struct sci_clk_provider - TI SCI clock provider representation
+ * @sci: Handle to the System Control Interface protocol handler
+ * @ops: Pointer to the SCI ops to be used by the clocks
+ * @dev: Device pointer for the clock provider
+ * @clk_data: Clock data
+ * @clocks: Clocks array for this device
+ */
+struct sci_clk_provider {
+ const struct ti_sci_handle *sci;
+ const struct ti_sci_clk_ops *ops;
+ struct device *dev;
+ const struct sci_clk_data *clk_data;
+ struct clk_hw **clocks;
+};
+
+/**
+ * struct sci_clk - TI SCI clock representation
+ * @hw: Hardware clock cookie for common clock framework
+ * @dev_id: Device index
+ * @clk_id: Clock index
+ * @node: Clocks list link
+ * @provider: Master clock provider
+ * @flags: Flags for the clock
+ */
+struct sci_clk {
+ struct clk_hw hw;
+ u16 dev_id;
+ u8 clk_id;
+ struct list_head node;
+ struct sci_clk_provider *provider;
+ u8 flags;
+};
+
+#define to_sci_clk(_hw) container_of(_hw, struct sci_clk, hw)
+
+/**
+ * sci_clk_prepare - Prepare (enable) a TI SCI clock
+ * @hw: clock to prepare
+ *
+ * Prepares a clock to be actively used. Returns the SCI protocol status.
+ */
+static int sci_clk_prepare(struct clk_hw *hw)
+{
+ struct sci_clk *clk = to_sci_clk(hw);
+ bool enable_ssc = clk->flags & SCI_CLK_SSC_ENABLE;
+ bool allow_freq_change = clk->flags & SCI_CLK_ALLOW_FREQ_CHANGE;
+ bool input_termination = clk->flags & SCI_CLK_INPUT_TERMINATION;
+
+ return clk->provider->ops->get_clock(clk->provider->sci, clk->dev_id,
+ clk->clk_id, enable_ssc,
+ allow_freq_change,
+ input_termination);
+}
+
+/**
+ * sci_clk_unprepare - Un-prepares (disables) a TI SCI clock
+ * @hw: clock to unprepare
+ *
+ * Un-prepares a clock from active state.
+ */
+static void sci_clk_unprepare(struct clk_hw *hw)
+{
+ struct sci_clk *clk = to_sci_clk(hw);
+ int ret;
+
+ ret = clk->provider->ops->put_clock(clk->provider->sci, clk->dev_id,
+ clk->clk_id);
+ if (ret)
+ dev_err(clk->provider->dev,
+ "unprepare failed for dev=%d, clk=%d, ret=%d\n",
+ clk->dev_id, clk->clk_id, ret);
+}
+
+/**
+ * sci_clk_is_prepared - Check if a TI SCI clock is prepared or not
+ * @hw: clock to check status for
+ *
+ * Checks if a clock is prepared (enabled) in hardware. Returns non-zero
+ * value if clock is enabled, zero otherwise.
+ */
+static int sci_clk_is_prepared(struct clk_hw *hw)
+{
+ struct sci_clk *clk = to_sci_clk(hw);
+ bool req_state, current_state;
+ int ret;
+
+ ret = clk->provider->ops->is_on(clk->provider->sci, clk->dev_id,
+ clk->clk_id, &req_state,
+ ¤t_state);
+ if (ret) {
+ dev_err(clk->provider->dev,
+ "is_prepared failed for dev=%d, clk=%d, ret=%d\n",
+ clk->dev_id, clk->clk_id, ret);
+ return 0;
+ }
+
+ return req_state;
+}
+
+/**
+ * sci_clk_recalc_rate - Get clock rate for a TI SCI clock
+ * @hw: clock to get rate for
+ * @parent_rate: parent rate provided by common clock framework, not used
+ *
+ * Gets the current clock rate of a TI SCI clock. Returns the current
+ * clock rate, or zero in failure.
+ */
+static unsigned long sci_clk_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct sci_clk *clk = to_sci_clk(hw);
+ u64 freq;
+ int ret;
+
+ ret = clk->provider->ops->get_freq(clk->provider->sci, clk->dev_id,
+ clk->clk_id, &freq);
+ if (ret) {
+ dev_err(clk->provider->dev,
+ "recalc-rate failed for dev=%d, clk=%d, ret=%d\n",
+ clk->dev_id, clk->clk_id, ret);
+ return 0;
+ }
+
+ return freq;
+}
+
+/**
+ * sci_clk_determine_rate - Determines a clock rate a clock can be set to
+ * @hw: clock to change rate for
+ * @req: requested rate configuration for the clock
+ *
+ * Determines a suitable clock rate and parent for a TI SCI clock.
+ * The parent handling is un-used, as generally the parent clock rates
+ * are not known by the kernel; instead these are internally handled
+ * by the firmware. Returns 0 on success, negative error value on failure.
+ */
+static int sci_clk_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ struct sci_clk *clk = to_sci_clk(hw);
+ int ret;
+ u64 new_rate;
+
+ ret = clk->provider->ops->get_best_match_freq(clk->provider->sci,
+ clk->dev_id,
+ clk->clk_id,
+ req->min_rate,
+ req->rate,
+ req->max_rate,
+ &new_rate);
+ if (ret) {
+ dev_err(clk->provider->dev,
+ "determine-rate failed for dev=%d, clk=%d, ret=%d\n",
+ clk->dev_id, clk->clk_id, ret);
+ return ret;
+ }
+
+ req->rate = new_rate;
+
+ return 0;
+}
+
+/**
+ * sci_clk_set_rate - Set rate for a TI SCI clock
+ * @hw: clock to change rate for
+ * @rate: target rate for the clock
+ * @parent_rate: rate of the clock parent, not used for TI SCI clocks
+ *
+ * Sets a clock frequency for a TI SCI clock. Returns the TI SCI
+ * protocol status.
+ */
+static int sci_clk_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct sci_clk *clk = to_sci_clk(hw);
+
+ return clk->provider->ops->set_freq(clk->provider->sci, clk->dev_id,
+ clk->clk_id, rate, rate, rate);
+}
+
+/**
+ * sci_clk_get_parent - Get the current parent of a TI SCI clock
+ * @hw: clock to get parent for
+ *
+ * Returns the index of the currently selected parent for a TI SCI clock.
+ */
+static u8 sci_clk_get_parent(struct clk_hw *hw)
+{
+ struct sci_clk *clk = to_sci_clk(hw);
+ u8 parent_id;
+ int ret;
+
+ ret = clk->provider->ops->get_parent(clk->provider->sci, clk->dev_id,
+ clk->clk_id, &parent_id);
+ if (ret) {
+ dev_err(clk->provider->dev,
+ "get-parent failed for dev=%d, clk=%d, ret=%d\n",
+ clk->dev_id, clk->clk_id, ret);
+ return 0;
+ }
+
+ return parent_id - clk->clk_id - 1;
+}
+
+/**
+ * sci_clk_set_parent - Set the parent of a TI SCI clock
+ * @hw: clock to set parent for
+ * @index: new parent index for the clock
+ *
+ * Sets the parent of a TI SCI clock. Return TI SCI protocol status.
+ */
+static int sci_clk_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct sci_clk *clk = to_sci_clk(hw);
+
+ return clk->provider->ops->set_parent(clk->provider->sci, clk->dev_id,
+ clk->clk_id,
+ index + 1 + clk->clk_id);
+}
+
+static const struct clk_ops sci_clk_ops = {
+ .prepare = sci_clk_prepare,
+ .unprepare = sci_clk_unprepare,
+ .is_prepared = sci_clk_is_prepared,
+ .recalc_rate = sci_clk_recalc_rate,
+ .determine_rate = sci_clk_determine_rate,
+ .set_rate = sci_clk_set_rate,
+ .get_parent = sci_clk_get_parent,
+ .set_parent = sci_clk_set_parent,
+};
+
+/**
+ * _sci_clk_get - Gets a handle for an SCI clock
+ * @provider: Handle to SCI clock provider
+ * @dev_id: device ID for the clock to register
+ * @clk_id: clock ID for the clock to register
+ *
+ * Gets a handle to an existing TI SCI hw clock, or builds a new clock
+ * entry and registers it with the common clock framework. Called from
+ * the common clock framework, when a corresponding of_clk_get call is
+ * executed, or recursively from itself when parsing parent clocks.
+ * Returns a pointer to the hw clock struct, or ERR_PTR value in failure.
+ */
+static struct clk_hw *_sci_clk_build(struct sci_clk_provider *provider,
+ u16 dev_id, u8 clk_id)
+{
+ struct clk_init_data init = { NULL };
+ struct sci_clk *sci_clk = NULL;
+ char *name = NULL;
+ char **parent_names = NULL;
+ int i;
+ int ret;
+
+ sci_clk = devm_kzalloc(provider->dev, sizeof(*sci_clk), GFP_KERNEL);
+ if (!sci_clk)
+ return ERR_PTR(-ENOMEM);
+
+ sci_clk->dev_id = dev_id;
+ sci_clk->clk_id = clk_id;
+ sci_clk->provider = provider;
+
+ ret = provider->ops->get_num_parents(provider->sci, dev_id,
+ clk_id,
+ &init.num_parents);
+ if (ret)
+ goto err;
+
+ name = kasprintf(GFP_KERNEL, "%s:%d:%d", dev_name(provider->dev),
+ sci_clk->dev_id, sci_clk->clk_id);
+
+ init.name = name;
+
+ /*
+ * From kernel point of view, we only care about a clocks parents,
+ * if it has more than 1 possible parent. In this case, it is going
+ * to have mux functionality. Otherwise it is going to act as a root
+ * clock.
+ */
+ if (init.num_parents < 2)
+ init.num_parents = 0;
+
+ if (init.num_parents) {
+ parent_names = kcalloc(init.num_parents, sizeof(char *),
+ GFP_KERNEL);
+
+ if (!parent_names) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ for (i = 0; i < init.num_parents; i++) {
+ char *parent_name;
+
+ parent_name = kasprintf(GFP_KERNEL, "%s:%d:%d",
+ dev_name(provider->dev),
+ sci_clk->dev_id,
+ sci_clk->clk_id + 1 + i);
+ if (!parent_name) {
+ ret = -ENOMEM;
+ goto err;
+ }
+ parent_names[i] = parent_name;
+ }
+ init.parent_names = (void *)parent_names;
+ }
+
+ init.ops = &sci_clk_ops;
+ sci_clk->hw.init = &init;
+
+ ret = devm_clk_hw_register(provider->dev, &sci_clk->hw);
+ if (ret)
+ dev_err(provider->dev, "failed clk register with %d\n", ret);
+
+err:
+ if (parent_names) {
+ for (i = 0; i < init.num_parents; i++)
+ kfree(parent_names[i]);
+
+ kfree(parent_names);
+ }
+
+ kfree(name);
+
+ if (ret)
+ return ERR_PTR(ret);
+
+ return &sci_clk->hw;
+}
+
+/**
+ * sci_clk_get - Xlate function for getting clock handles
+ * @clkspec: device tree clock specifier
+ * @data: pointer to the clock provider
+ *
+ * Xlate function for retrieving clock TI SCI hw clock handles based on
+ * device tree clock specifier. Called from the common clock framework,
+ * when a corresponding of_clk_get call is executed. Returns a pointer
+ * to the TI SCI hw clock struct, or ERR_PTR value in failure.
+ */
+static struct clk_hw *sci_clk_get(struct of_phandle_args *clkspec, void *data)
+{
+ struct sci_clk_provider *provider = data;
+ u16 dev_id;
+ u8 clk_id;
+ const struct sci_clk_data *clks = provider->clk_data;
+ struct clk_hw **clocks = provider->clocks;
+
+ if (clkspec->args_count != 2)
+ return ERR_PTR(-EINVAL);
+
+ dev_id = clkspec->args[0];
+ clk_id = clkspec->args[1];
+
+ while (clks->num_clks) {
+ if (clks->dev == dev_id) {
+ if (clk_id >= clks->num_clks)
+ return ERR_PTR(-EINVAL);
+
+ return clocks[clk_id];
+ }
+
+ clks++;
+ }
+
+ return ERR_PTR(-ENODEV);
+}
+
+static int ti_sci_init_clocks(struct sci_clk_provider *p)
+{
+ const struct sci_clk_data *data = p->clk_data;
+ struct clk_hw *hw;
+ int i;
+
+ while (data->num_clks) {
+ p->clocks = devm_kcalloc(p->dev, data->num_clks,
+ sizeof(struct sci_clk),
+ GFP_KERNEL);
+ if (!p->clocks)
+ return -ENOMEM;
+
+ for (i = 0; i < data->num_clks; i++) {
+ hw = _sci_clk_build(p, data->dev, i);
+ if (!IS_ERR(hw)) {
+ p->clocks[i] = hw;
+ continue;
+ }
+
+ /* Skip any holes in the clock lists */
+ if (PTR_ERR(hw) == -ENODEV)
+ continue;
+
+ return PTR_ERR(hw);
+ }
+ data++;
+ }
+
+ return 0;
+}
+
+static const struct sci_clk_data k2g_clk_data[] = {
+ /* pmmc */
+ { .dev = 0x0, .num_clks = 4 },
+
+ /* mlb0 */
+ { .dev = 0x1, .num_clks = 5 },
+
+ /* dss0 */
+ { .dev = 0x2, .num_clks = 2 },
+
+ /* mcbsp0 */
+ { .dev = 0x3, .num_clks = 8 },
+
+ /* mcasp0 */
+ { .dev = 0x4, .num_clks = 8 },
+
+ /* mcasp1 */
+ { .dev = 0x5, .num_clks = 8 },
+
+ /* mcasp2 */
+ { .dev = 0x6, .num_clks = 8 },
+
+ /* dcan0 */
+ { .dev = 0x8, .num_clks = 2 },
+
+ /* dcan1 */
+ { .dev = 0x9, .num_clks = 2 },
+
+ /* emif0 */
+ { .dev = 0xa, .num_clks = 6 },
+
+ /* mmchs0 */
+ { .dev = 0xb, .num_clks = 3 },
+
+ /* mmchs1 */
+ { .dev = 0xc, .num_clks = 3 },
+
+ /* gpmc0 */
+ { .dev = 0xd, .num_clks = 1 },
+
+ /* elm0 */
+ { .dev = 0xe, .num_clks = 1 },
+
+ /* spi0 */
+ { .dev = 0x10, .num_clks = 1 },
+
+ /* spi1 */
+ { .dev = 0x11, .num_clks = 1 },
+
+ /* spi2 */
+ { .dev = 0x12, .num_clks = 1 },
+
+ /* spi3 */
+ { .dev = 0x13, .num_clks = 1 },
+
+ /* icss0 */
+ { .dev = 0x14, .num_clks = 6 },
+
+ /* icss1 */
+ { .dev = 0x15, .num_clks = 6 },
+
+ /* usb0 */
+ { .dev = 0x16, .num_clks = 7 },
+
+ /* usb1 */
+ { .dev = 0x17, .num_clks = 7 },
+
+ /* nss0 */
+ { .dev = 0x18, .num_clks = 14 },
+
+ /* pcie0 */
+ { .dev = 0x19, .num_clks = 1 },
+
+ /* gpio0 */
+ { .dev = 0x1b, .num_clks = 1 },
+
+ /* gpio1 */
+ { .dev = 0x1c, .num_clks = 1 },
+
+ /* timer64_0 */
+ { .dev = 0x1d, .num_clks = 9 },
+
+ /* timer64_1 */
+ { .dev = 0x1e, .num_clks = 9 },
+
+ /* timer64_2 */
+ { .dev = 0x1f, .num_clks = 9 },
+
+ /* timer64_3 */
+ { .dev = 0x20, .num_clks = 9 },
+
+ /* timer64_4 */
+ { .dev = 0x21, .num_clks = 9 },
+
+ /* timer64_5 */
+ { .dev = 0x22, .num_clks = 9 },
+
+ /* timer64_6 */
+ { .dev = 0x23, .num_clks = 9 },
+
+ /* msgmgr0 */
+ { .dev = 0x25, .num_clks = 1 },
+
+ /* bootcfg0 */
+ { .dev = 0x26, .num_clks = 1 },
+
+ /* arm_bootrom0 */
+ { .dev = 0x27, .num_clks = 1 },
+
+ /* dsp_bootrom0 */
+ { .dev = 0x29, .num_clks = 1 },
+
+ /* debugss0 */
+ { .dev = 0x2b, .num_clks = 8 },
+
+ /* uart0 */
+ { .dev = 0x2c, .num_clks = 1 },
+
+ /* uart1 */
+ { .dev = 0x2d, .num_clks = 1 },
+
+ /* uart2 */
+ { .dev = 0x2e, .num_clks = 1 },
+
+ /* ehrpwm0 */
+ { .dev = 0x2f, .num_clks = 1 },
+
+ /* ehrpwm1 */
+ { .dev = 0x30, .num_clks = 1 },
+
+ /* ehrpwm2 */
+ { .dev = 0x31, .num_clks = 1 },
+
+ /* ehrpwm3 */
+ { .dev = 0x32, .num_clks = 1 },
+
+ /* ehrpwm4 */
+ { .dev = 0x33, .num_clks = 1 },
+
+ /* ehrpwm5 */
+ { .dev = 0x34, .num_clks = 1 },
+
+ /* eqep0 */
+ { .dev = 0x35, .num_clks = 1 },
+
+ /* eqep1 */
+ { .dev = 0x36, .num_clks = 1 },
+
+ /* eqep2 */
+ { .dev = 0x37, .num_clks = 1 },
+
+ /* ecap0 */
+ { .dev = 0x38, .num_clks = 1 },
+
+ /* ecap1 */
+ { .dev = 0x39, .num_clks = 1 },
+
+ /* i2c0 */
+ { .dev = 0x3a, .num_clks = 1 },
+
+ /* i2c1 */
+ { .dev = 0x3b, .num_clks = 1 },
+
+ /* i2c2 */
+ { .dev = 0x3c, .num_clks = 1 },
+
+ /* edma0 */
+ { .dev = 0x3f, .num_clks = 2 },
+
+ /* semaphore0 */
+ { .dev = 0x40, .num_clks = 1 },
+
+ /* intc0 */
+ { .dev = 0x41, .num_clks = 1 },
+
+ /* gic0 */
+ { .dev = 0x42, .num_clks = 1 },
+
+ /* qspi0 */
+ { .dev = 0x43, .num_clks = 5 },
+
+ /* arm_64b_counter0 */
+ { .dev = 0x44, .num_clks = 2 },
+
+ /* tetris0 */
+ { .dev = 0x45, .num_clks = 2 },
+
+ /* cgem0 */
+ { .dev = 0x46, .num_clks = 2 },
+
+ /* msmc0 */
+ { .dev = 0x47, .num_clks = 1 },
+
+ /* cbass0 */
+ { .dev = 0x49, .num_clks = 1 },
+
+ /* board0 */
+ { .dev = 0x4c, .num_clks = 36 },
+
+ /* edma1 */
+ { .dev = 0x4f, .num_clks = 2 },
+ { .num_clks = 0 },
+};
+
+static const struct of_device_id ti_sci_clk_of_match[] = {
+ { .compatible = "ti,k2g-sci-clk", .data = &k2g_clk_data },
+ { /* Sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, ti_sci_clk_of_match);
+
+/**
+ * ti_sci_clk_probe - Probe function for the TI SCI clock driver
+ * @pdev: platform device pointer to be probed
+ *
+ * Probes the TI SCI clock device. Allocates a new clock provider
+ * and registers this to the common clock framework. Also applies
+ * any required flags to the identified clocks via clock lists
+ * supplied from DT. Returns 0 for success, negative error value
+ * for failure.
+ */
+static int ti_sci_clk_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct sci_clk_provider *provider;
+ const struct ti_sci_handle *handle;
+ const struct sci_clk_data *data;
+ int ret;
+
+ data = of_device_get_match_data(dev);
+ if (!data)
+ return -EINVAL;
+
+ handle = devm_ti_sci_get_handle(dev);
+ if (IS_ERR(handle))
+ return PTR_ERR(handle);
+
+ provider = devm_kzalloc(dev, sizeof(*provider), GFP_KERNEL);
+ if (!provider)
+ return -ENOMEM;
+
+ provider->clk_data = data;
+
+ provider->sci = handle;
+ provider->ops = &handle->ops.clk_ops;
+ provider->dev = dev;
+
+ ret = ti_sci_init_clocks(provider);
+ if (ret) {
+ pr_err("ti-sci-init-clocks failed.\n");
+ return ret;
+ }
+
+ return of_clk_add_hw_provider(np, sci_clk_get, provider);
+}
+
+/**
+ * ti_sci_clk_remove - Remove TI SCI clock device
+ * @pdev: platform device pointer for the device to be removed
+ *
+ * Removes the TI SCI device. Unregisters the clock provider registered
+ * via common clock framework. Any memory allocated for the device will
+ * be free'd silently via the devm framework. Returns 0 always.
+ */
+static int ti_sci_clk_remove(struct platform_device *pdev)
+{
+ of_clk_del_provider(pdev->dev.of_node);
+
+ return 0;
+}
+
+static struct platform_driver ti_sci_clk_driver = {
+ .probe = ti_sci_clk_probe,
+ .remove = ti_sci_clk_remove,
+ .driver = {
+ .name = "ti-sci-clk",
+ .of_match_table = of_match_ptr(ti_sci_clk_of_match),
+ },
+};
+module_platform_driver(ti_sci_clk_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("TI System Control Interface(SCI) Clock driver");
+MODULE_AUTHOR("Tero Kristo");
+MODULE_ALIAS("platform:ti-sci-clk");
projects / platform / kernel / linux-rpi.git / commitdiff