1 files changed, 583 insertions, 0 deletions
diff --git a/drivers/bus/ti-sysc.c b/drivers/bus/ti-sysc.c
new file mode 100644
index 000000000000..c3c76a1ea8a8
--- /dev/null
+++ b/drivers/bus/ti-sysc.c
@@ -0,0 +1,583 @@
+/*
+ * ti-sysc.c - Texas Instruments sysc interconnect target driver
+ *
+ * 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/io.h>
+#include <linux/clk.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+
+enum sysc_registers {
+	SYSC_REVISION,
+	SYSC_SYSCONFIG,
+	SYSC_SYSSTATUS,
+	SYSC_MAX_REGS,
+};
+
+static const char * const reg_names[] = { "rev", "sysc", "syss", };
+
+enum sysc_clocks {
+	SYSC_FCK,
+	SYSC_ICK,
+	SYSC_MAX_CLOCKS,
+};
+
+static const char * const clock_names[] = { "fck", "ick", };
+
+/**
+ * struct sysc - TI sysc interconnect target module registers and capabilities
+ * @dev: struct device pointer
+ * @module_pa: physical address of the interconnect target module
+ * @module_size: size of the interconnect target module
+ * @module_va: virtual address of the interconnect target module
+ * @offsets: register offsets from module base
+ * @clocks: clocks used by the interconnect target module
+ * @legacy_mode: configured for legacy mode if set
+ */
+struct sysc {
+	struct device *dev;
+	u64 module_pa;
+	u32 module_size;
+	void __iomem *module_va;
+	int offsets[SYSC_MAX_REGS];
+	struct clk *clocks[SYSC_MAX_CLOCKS];
+	const char *legacy_mode;
+};
+
+static u32 sysc_read_revision(struct sysc *ddata)
+{
+	return readl_relaxed(ddata->module_va +
+			     ddata->offsets[SYSC_REVISION]);
+}
+
+static int sysc_get_one_clock(struct sysc *ddata,
+			      enum sysc_clocks index)
+{
+	const char *name;
+	int error;
+
+	switch (index) {
+	case SYSC_FCK:
+		break;
+	case SYSC_ICK:
+		break;
+	default:
+		return -EINVAL;
+	}
+	name = clock_names[index];
+
+	ddata->clocks[index] = devm_clk_get(ddata->dev, name);
+	if (IS_ERR(ddata->clocks[index])) {
+		if (PTR_ERR(ddata->clocks[index]) == -ENOENT)
+			return 0;
+
+		dev_err(ddata->dev, "clock get error for %s: %li\n",
+			name, PTR_ERR(ddata->clocks[index]));
+
+		return PTR_ERR(ddata->clocks[index]);
+	}
+
+	error = clk_prepare(ddata->clocks[index]);
+	if (error) {
+		dev_err(ddata->dev, "clock prepare error for %s: %i\n",
+			name, error);
+
+		return error;
+	}
+
+	return 0;
+}
+
+static int sysc_get_clocks(struct sysc *ddata)
+{
+	int i, error;
+
+	if (ddata->legacy_mode)
+		return 0;
+
+	for (i = 0; i < SYSC_MAX_CLOCKS; i++) {
+		error = sysc_get_one_clock(ddata, i);
+		if (error && error != -ENOENT)
+			return error;
+	}
+
+	return 0;
+}
+
+/**
+ * sysc_parse_and_check_child_range - parses module IO region from ranges
+ * @ddata: device driver data
+ *
+ * In general we only need rev, syss, and sysc registers and not the whole
+ * module range. But we do want the offsets for these registers from the
+ * module base. This allows us to check them against the legacy hwmod
+ * platform data. Let's also check the ranges are configured properly.
+ */
+static int sysc_parse_and_check_child_range(struct sysc *ddata)
+{
+	struct device_node *np = ddata->dev->of_node;
+	const __be32 *ranges;
+	u32 nr_addr, nr_size;
+	int len, error;
+
+	ranges = of_get_property(np, "ranges", &len);
+	if (!ranges) {
+		dev_err(ddata->dev, "missing ranges for %pOF\n", np);
+
+		return -ENOENT;
+	}
+
+	len /= sizeof(*ranges);
+
+	if (len < 3) {
+		dev_err(ddata->dev, "incomplete ranges for %pOF\n", np);
+
+		return -EINVAL;
+	}
+
+	error = of_property_read_u32(np, "#address-cells", &nr_addr);
+	if (error)
+		return -ENOENT;
+
+	error = of_property_read_u32(np, "#size-cells", &nr_size);
+	if (error)
+		return -ENOENT;
+
+	if (nr_addr != 1 || nr_size != 1) {
+		dev_err(ddata->dev, "invalid ranges for %pOF\n", np);
+
+		return -EINVAL;
+	}
+
+	ranges++;
+	ddata->module_pa = of_translate_address(np, ranges++);
+	ddata->module_size = be32_to_cpup(ranges);
+
+	dev_dbg(ddata->dev, "interconnect target 0x%llx size 0x%x for %pOF\n",
+		ddata->module_pa, ddata->module_size, np);
+
+	return 0;
+}
+
+/**
+ * sysc_check_one_child - check child configuration
+ * @ddata: device driver data
+ * @np: child device node
+ *
+ * Let's avoid messy situations where we have new interconnect target
+ * node but children have "ti,hwmods". These belong to the interconnect
+ * target node and are managed by this driver.
+ */
+static int sysc_check_one_child(struct sysc *ddata,
+				struct device_node *np)
+{
+	const char *name;
+
+	name = of_get_property(np, "ti,hwmods", NULL);
+	if (name)
+		dev_warn(ddata->dev, "really a child ti,hwmods property?");
+
+	return 0;
+}
+
+static int sysc_check_children(struct sysc *ddata)
+{
+	struct device_node *child;
+	int error;
+
+	for_each_child_of_node(ddata->dev->of_node, child) {
+		error = sysc_check_one_child(ddata, child);
+		if (error)
+			return error;
+	}
+
+	return 0;
+}
+
+/**
+ * sysc_parse_one - parses the interconnect target module registers
+ * @ddata: device driver data
+ * @reg: register to parse
+ */
+static int sysc_parse_one(struct sysc *ddata, enum sysc_registers reg)
+{
+	struct resource *res;
+	const char *name;
+
+	switch (reg) {
+	case SYSC_REVISION:
+	case SYSC_SYSCONFIG:
+	case SYSC_SYSSTATUS:
+		name = reg_names[reg];
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	res = platform_get_resource_byname(to_platform_device(ddata->dev),
+					   IORESOURCE_MEM, name);
+	if (!res) {
+		dev_dbg(ddata->dev, "has no %s register\n", name);
+		ddata->offsets[reg] = -ENODEV;
+
+		return 0;
+	}
+
+	ddata->offsets[reg] = res->start - ddata->module_pa;
+
+	return 0;
+}
+
+static int sysc_parse_registers(struct sysc *ddata)
+{
+	int i, error;
+
+	for (i = 0; i < SYSC_MAX_REGS; i++) {
+		error = sysc_parse_one(ddata, i);
+		if (error)
+			return error;
+	}
+
+	return 0;
+}
+
+/**
+ * sysc_check_registers - check for misconfigured register overlaps
+ * @ddata: device driver data
+ */
+static int sysc_check_registers(struct sysc *ddata)
+{
+	int i, j, nr_regs = 0, nr_matches = 0;
+
+	for (i = 0; i < SYSC_MAX_REGS; i++) {
+		if (ddata->offsets[i] < 0)
+			continue;
+
+		if (ddata->offsets[i] > (ddata->module_size - 4)) {
+			dev_err(ddata->dev, "register outside module range");
+
+				return -EINVAL;
+		}
+
+		for (j = 0; j < SYSC_MAX_REGS; j++) {
+			if (ddata->offsets[j] < 0)
+				continue;
+
+			if (ddata->offsets[i] == ddata->offsets[j])
+				nr_matches++;
+		}
+		nr_regs++;
+	}
+
+	if (nr_regs < 1) {
+		dev_err(ddata->dev, "missing registers\n");
+
+		return -EINVAL;
+	}
+
+	if (nr_matches > nr_regs) {
+		dev_err(ddata->dev, "overlapping registers: (%i/%i)",
+			nr_regs, nr_matches);
+
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/**
+ * syc_ioremap - ioremap register space for the interconnect target module
+ * @ddata: deviec driver data
+ *
+ * Note that the interconnect target module registers can be anywhere
+ * within the first child device address space. For example, SGX has
+ * them at offset 0x1fc00 in the 32MB module address space. We just
+ * what we need around the interconnect target module registers.
+ */
+static int sysc_ioremap(struct sysc *ddata)
+{
+	u32 size = 0;
+
+	if (ddata->offsets[SYSC_SYSSTATUS] >= 0)
+		size = ddata->offsets[SYSC_SYSSTATUS];
+	else if (ddata->offsets[SYSC_SYSCONFIG] >= 0)
+		size = ddata->offsets[SYSC_SYSCONFIG];
+	else if (ddata->offsets[SYSC_REVISION] >= 0)
+		size = ddata->offsets[SYSC_REVISION];
+	else
+		return -EINVAL;
+
+	size &= 0xfff00;
+	size += SZ_256;
+
+	ddata->module_va = devm_ioremap(ddata->dev,
+					ddata->module_pa,
+					size);
+	if (!ddata->module_va)
+		return -EIO;
+
+	return 0;
+}
+
+/**
+ * sysc_map_and_check_registers - ioremap and check device registers
+ * @ddata: device driver data
+ */
+static int sysc_map_and_check_registers(struct sysc *ddata)
+{
+	int error;
+
+	error = sysc_parse_and_check_child_range(ddata);
+	if (error)
+		return error;
+
+	error = sysc_check_children(ddata);
+	if (error)
+		return error;
+
+	error = sysc_parse_registers(ddata);
+	if (error)
+		return error;
+
+	error = sysc_ioremap(ddata);
+	if (error)
+		return error;
+
+	error = sysc_check_registers(ddata);
+	if (error)
+		return error;
+
+	return 0;
+}
+
+/**
+ * sysc_show_rev - read and show interconnect target module revision
+ * @bufp: buffer to print the information to
+ * @ddata: device driver data
+ */
+static int sysc_show_rev(char *bufp, struct sysc *ddata)
+{
+	int error, len;
+
+	if (ddata->offsets[SYSC_REVISION] < 0)
+		return sprintf(bufp, ":NA");
+
+	error = pm_runtime_get_sync(ddata->dev);
+	if (error < 0) {
+		pm_runtime_put_noidle(ddata->dev);
+
+		return 0;
+	}
+
+	len = sprintf(bufp, ":%08x", sysc_read_revision(ddata));
+
+	pm_runtime_mark_last_busy(ddata->dev);
+	pm_runtime_put_autosuspend(ddata->dev);
+
+	return len;
+}
+
+static int sysc_show_reg(struct sysc *ddata,
+			 char *bufp, enum sysc_registers reg)
+{
+	if (ddata->offsets[reg] < 0)
+		return sprintf(bufp, ":NA");
+
+	return sprintf(bufp, ":%x", ddata->offsets[reg]);
+}
+
+/**
+ * sysc_show_registers - show information about interconnect target module
+ * @ddata: device driver data
+ */
+static void sysc_show_registers(struct sysc *ddata)
+{
+	char buf[128];
+	char *bufp = buf;
+	int i;
+
+	for (i = 0; i < SYSC_MAX_REGS; i++)
+		bufp += sysc_show_reg(ddata, bufp, i);
+
+	bufp += sysc_show_rev(bufp, ddata);
+
+	dev_dbg(ddata->dev, "%llx:%x%s\n",
+		ddata->module_pa, ddata->module_size,
+		buf);
+}
+
+static int __maybe_unused sysc_runtime_suspend(struct device *dev)
+{
+	struct sysc *ddata;
+	int i;
+
+	ddata = dev_get_drvdata(dev);
+
+	if (ddata->legacy_mode)
+		return 0;
+
+	for (i = 0; i < SYSC_MAX_CLOCKS; i++) {
+		if (IS_ERR_OR_NULL(ddata->clocks[i]))
+			continue;
+		clk_disable(ddata->clocks[i]);
+	}
+
+	return 0;
+}
+
+static int __maybe_unused sysc_runtime_resume(struct device *dev)
+{
+	struct sysc *ddata;
+	int i, error;
+
+	ddata = dev_get_drvdata(dev);
+
+	if (ddata->legacy_mode)
+		return 0;
+
+	for (i = 0; i < SYSC_MAX_CLOCKS; i++) {
+		if (IS_ERR_OR_NULL(ddata->clocks[i]))
+			continue;
+		error = clk_enable(ddata->clocks[i]);
+		if (error)
+			return error;
+	}
+
+	return 0;
+}
+
+static const struct dev_pm_ops sysc_pm_ops = {
+	SET_RUNTIME_PM_OPS(sysc_runtime_suspend,
+			   sysc_runtime_resume,
+			   NULL)
+};
+
+static void sysc_unprepare(struct sysc *ddata)
+{
+	int i;
+
+	for (i = 0; i < SYSC_MAX_CLOCKS; i++) {
+		if (!IS_ERR_OR_NULL(ddata->clocks[i]))
+			clk_unprepare(ddata->clocks[i]);
+	}
+}
+
+static int sysc_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct sysc *ddata;
+	int error;
+
+	ddata = devm_kzalloc(&pdev->dev, sizeof(*ddata), GFP_KERNEL);
+	if (!ddata)
+		return -ENOMEM;
+
+	ddata->dev = &pdev->dev;
+	ddata->legacy_mode = of_get_property(np, "ti,hwmods", NULL);
+
+	error = sysc_get_clocks(ddata);
+	if (error)
+		return error;
+
+	error = sysc_map_and_check_registers(ddata);
+	if (error)
+		goto unprepare;
+
+	platform_set_drvdata(pdev, ddata);
+
+	pm_runtime_enable(ddata->dev);
+	error = pm_runtime_get_sync(ddata->dev);
+	if (error < 0) {
+		pm_runtime_put_noidle(ddata->dev);
+		pm_runtime_disable(ddata->dev);
+		goto unprepare;
+	}
+
+	pm_runtime_use_autosuspend(ddata->dev);
+
+	sysc_show_registers(ddata);
+
+	error = of_platform_populate(ddata->dev->of_node,
+				     NULL, NULL, ddata->dev);
+	if (error)
+		goto err;
+
+	pm_runtime_mark_last_busy(ddata->dev);
+	pm_runtime_put_autosuspend(ddata->dev);
+
+	return 0;
+
+err:
+	pm_runtime_dont_use_autosuspend(&pdev->dev);
+	pm_runtime_put_sync(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+unprepare:
+	sysc_unprepare(ddata);
+
+	return error;
+}
+
+static int sysc_remove(struct platform_device *pdev)
+{
+	struct sysc *ddata = platform_get_drvdata(pdev);
+	int error;
+
+	error = pm_runtime_get_sync(ddata->dev);
+	if (error < 0) {
+		pm_runtime_put_noidle(ddata->dev);
+		pm_runtime_disable(ddata->dev);
+		goto unprepare;
+	}
+
+	of_platform_depopulate(&pdev->dev);
+
+	pm_runtime_dont_use_autosuspend(&pdev->dev);
+	pm_runtime_put_sync(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+
+unprepare:
+	sysc_unprepare(ddata);
+
+	return 0;
+}
+
+static const struct of_device_id sysc_match[] = {
+	{ .compatible = "ti,sysc-omap2" },
+	{ .compatible = "ti,sysc-omap4" },
+	{ .compatible = "ti,sysc-omap4-simple" },
+	{ .compatible = "ti,sysc-omap3430-sr" },
+	{ .compatible = "ti,sysc-omap3630-sr" },
+	{ .compatible = "ti,sysc-omap4-sr" },
+	{ .compatible = "ti,sysc-omap3-sham" },
+	{ .compatible = "ti,sysc-omap-aes" },
+	{ .compatible = "ti,sysc-mcasp" },
+	{ .compatible = "ti,sysc-usb-host-fs" },
+	{  },
+};
+MODULE_DEVICE_TABLE(of, sysc_match);
+
+static struct platform_driver sysc_driver = {
+	.probe		= sysc_probe,
+	.remove		= sysc_remove,
+	.driver         = {
+		.name   = "ti-sysc",
+		.of_match_table	= sysc_match,
+		.pm = &sysc_pm_ops,
+	},
+};
+module_platform_driver(sysc_driver);
+
+MODULE_DESCRIPTION("TI sysc interconnect target driver");
+MODULE_LICENSE("GPL v2");