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-rw-r--r--drivers/bus/ti-sysc.c583
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");

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