diff options
Diffstat (limited to 'drivers/bus/ti-sysc.c')
| -rw-r--r-- | drivers/bus/ti-sysc.c | 583 |
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"); |