| Message ID | 1421078245-5531-1-git-send-email-geert+renesas@glider.be (mailing list archive) |
|---|---|
| State | Not Applicable |
| Delegated to: | Geert Uytterhoeven |
| Headers | show |
On Mon, Jan 12, 2015 at 04:57:25PM +0100, Geert Uytterhoeven wrote: > Add a reset driver for Renesas R-Mobile and SH-Mobile SoCs. It registers > a restart handler to trigger a soft power-on reset through the R-Mobile > System Controller. > As this is controlled by DT, the priority of this restart handler is 192, > to allow a watchdog driver to use priority 128. > > Note that we do not use syscon-reboot, as the HPB (Peripheral Bus > Bridge) semaphore should be acquired on systems where both the ARM and > SH core are in use. The driver can be extended later to support this, > when needed. > > Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> > Reviewed-by: Guenter Roeck <linux@roeck-us.net> > --- > Tested on R-Mobile A1 (r8a7740) and SH-Mobile AG5 (sh73a0). Please add DT binding documentation. -- Sebastian
On Mon, Jan 12, 2015 at 8:04 PM, Sebastian Reichel <sre@kernel.org> wrote: > On Mon, Jan 12, 2015 at 04:57:25PM +0100, Geert Uytterhoeven wrote: >> Add a reset driver for Renesas R-Mobile and SH-Mobile SoCs. It registers >> a restart handler to trigger a soft power-on reset through the R-Mobile >> System Controller. >> As this is controlled by DT, the priority of this restart handler is 192, >> to allow a watchdog driver to use priority 128. >> >> Note that we do not use syscon-reboot, as the HPB (Peripheral Bus >> Bridge) semaphore should be acquired on systems where both the ARM and >> SH core are in use. The driver can be extended later to support this, >> when needed. >> >> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> >> Reviewed-by: Guenter Roeck <linux@roeck-us.net> >> --- >> Tested on R-Mobile A1 (r8a7740) and SH-Mobile AG5 (sh73a0). > > Please add DT binding documentation. Sorry, I indeed should have referenced the DT binding documentation that's already queued up in -next for the PM domain support: https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/tree/Documentation/devicetree/bindings/power/renesas,sysc-rmobile.txt Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- To unsubscribe from this list: send the line "unsubscribe linux-sh" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig index 028e765045196f89..d743145e0001f466 100644 --- a/drivers/power/reset/Kconfig +++ b/drivers/power/reset/Kconfig @@ -159,5 +159,11 @@ config POWER_RESET_SYSCON help Reboot support for generic SYSCON mapped register reset. +config POWER_RESET_RMOBILE + tristate "Renesas R-Mobile reset driver" + depends on ARCH_RMOBILE || COMPILE_TEST + help + Reboot support for Renesas R-Mobile and SH-Mobile SoCs. + endif diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile index 1d4804d6b3237c1c..1631652009acc32d 100644 --- a/drivers/power/reset/Makefile +++ b/drivers/power/reset/Makefile @@ -18,3 +18,4 @@ obj-$(CONFIG_POWER_RESET_VEXPRESS) += vexpress-poweroff.o obj-$(CONFIG_POWER_RESET_XGENE) += xgene-reboot.o obj-$(CONFIG_POWER_RESET_KEYSTONE) += keystone-reset.o obj-$(CONFIG_POWER_RESET_SYSCON) += syscon-reboot.o +obj-$(CONFIG_POWER_RESET_RMOBILE) += rmobile-reset.o diff --git a/drivers/power/reset/rmobile-reset.c b/drivers/power/reset/rmobile-reset.c new file mode 100644 index 0000000000000000..ff3bbcfd03d1e7b4 --- /dev/null +++ b/drivers/power/reset/rmobile-reset.c @@ -0,0 +1,93 @@ +/* + * Renesas R-Mobile Reset Driver + * + * Copyright (C) 2014 Glider bvba + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ + +#include <linux/io.h> +#include <linux/module.h> +#include <linux/notifier.h> +#include <linux/of_address.h> +#include <linux/platform_device.h> +#include <linux/printk.h> +#include <linux/reboot.h> + + +/* SYSC Register Bank 2 */ +#define RESCNT2 0x20 /* Reset Control Register 2 */ + +/* Reset Control Register 2 */ +#define RESCNT2_PRES 0x80000000 /* Soft power-on reset */ + + +static void __iomem *sysc_base2; + +static int rmobile_reset_handler(struct notifier_block *this, + unsigned long mode, void *cmd) +{ + pr_debug("%s %lu\n", __func__, mode); + + /* Let's assume we have acquired the HPB semaphore */ + writel(RESCNT2_PRES, sysc_base2 + RESCNT2); + + return NOTIFY_DONE; +} + +static struct notifier_block rmobile_reset_nb = { + .notifier_call = rmobile_reset_handler, + .priority = 192, +}; + +static int rmobile_reset_probe(struct platform_device *pdev) +{ + int error; + + sysc_base2 = of_iomap(pdev->dev.of_node, 1); + if (!sysc_base2) + return -ENODEV; + + error = register_restart_handler(&rmobile_reset_nb); + if (error) { + dev_err(&pdev->dev, + "cannot register restart handler (err=%d)\n", error); + goto fail_unmap; + } + + return 0; + +fail_unmap: + iounmap(sysc_base2); + return error; +} + +static int rmobile_reset_remove(struct platform_device *pdev) +{ + unregister_restart_handler(&rmobile_reset_nb); + iounmap(sysc_base2); + return 0; +} + +static const struct of_device_id rmobile_reset_of_match[] = { + { .compatible = "renesas,sysc-rmobile", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, rmobile_reset_of_match); + +static struct platform_driver rmobile_reset_driver = { + .probe = rmobile_reset_probe, + .remove = rmobile_reset_remove, + .driver = { + .name = "rmobile_reset", + .of_match_table = rmobile_reset_of_match, + }, +}; + +module_platform_driver(rmobile_reset_driver); + +MODULE_DESCRIPTION("Renesas R-Mobile Reset Driver"); +MODULE_AUTHOR("Geert Uytterhoeven <geert+renesas@glider.be>"); +MODULE_LICENSE("GPL v2");