On Mon, Apr 17, 2017 at 9:29 PM, Hauke Mehrtens <hauke@xxxxxxxxxx> wrote: > From: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx> > > The reset controllers (on xRX200 and newer SoCs have two of them) are > provided by the RCU module. This was initially implemented as a simple > reset controller. However, the RCU module provides more functionality > (ethernet GPHYs, USB PHY, etc.), which makes it a MFD device. > The old reset controller driver implementation from > arch/mips/lantiq/xway/reset.c did not honor this fact. > > For some devices the request and the status bits are different. > > Signed-off-by: Hauke Mehrtens <hauke@xxxxxxxxxx> I think you should CC the reset controller framework maintainer (Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>) as well > --- > .../devicetree/bindings/reset/lantiq,rcu-reset.txt | 43 ++++ > arch/mips/lantiq/xway/reset.c | 68 ------ > drivers/reset/Kconfig | 6 + > drivers/reset/Makefile | 1 + > drivers/reset/reset-lantiq-rcu.c | 231 +++++++++++++++++++++ > 5 files changed, 281 insertions(+), 68 deletions(-) > create mode 100644 Documentation/devicetree/bindings/reset/lantiq,rcu-reset.txt > create mode 100644 drivers/reset/reset-lantiq-rcu.c > > diff --git a/Documentation/devicetree/bindings/reset/lantiq,rcu-reset.txt b/Documentation/devicetree/bindings/reset/lantiq,rcu-reset.txt > new file mode 100644 > index 000000000000..7f097d16bbb7 > --- /dev/null > +++ b/Documentation/devicetree/bindings/reset/lantiq,rcu-reset.txt > @@ -0,0 +1,43 @@ > +Lantiq XWAY SoC RCU reset controller binding > +============================================ > + > +This binding describes a reset-controller found on the RCU module on Lantiq > +XWAY SoCs. > + > + > +------------------------------------------------------------------------------- > +Required properties (controller (parent) node): > +- compatible : Should be "lantiq,rcu-reset" > +- lantiq,rcu-syscon : A phandle to the RCU syscon, the reset register > + offset and the status register offset. > +- #reset-cells : Specifies the number of cells needed to encode the > + reset line, should be 1. > + > +Optional properties: > +- reset-status : The request status bit. For some bits the request bit > + and the status bit are different. This is depending > + on the SoC. If the reset-status bit does not match > + the reset-request bit, put the reset number into the > + reset-request property and the status bit at the same > + index into the reset-status property. If no > + reset-request bit is given here, the driver assume > + status and request bit are the same. > +- reset-request : The reset request bit, to map it to the reset-status > + bit. > + > + > +------------------------------------------------------------------------------- > +Example for the reset-controllers on the xRX200 SoCs: > + rcu_reset0: rcu_reset { > + compatible = "lantiq,rcu-reset"; > + lantiq,rcu-syscon = <&rcu0 0x10 0x14>; > + #reset-cells = <1>; > + reset-request = <31>, <29>, <21>, <19>, <16>, <12>; > + reset-status = <30>, <28>, <16>, <25>, <5>, <24>; > + }; > + > + rcu_reset1: rcu_reset { > + compatible = "lantiq,rcu-reset"; > + lantiq,rcu-syscon = <&rcu0 0x48 0x24>; > + #reset-cells = <1>; > + }; > diff --git a/arch/mips/lantiq/xway/reset.c b/arch/mips/lantiq/xway/reset.c > index 2dedcf939901..5cb9309b0047 100644 > --- a/arch/mips/lantiq/xway/reset.c > +++ b/arch/mips/lantiq/xway/reset.c probably a left-over of my patch: can't this arch/mips/lantiq/xway/reset.c change go into PATCH #13 as well? > @@ -194,74 +194,6 @@ int xrx200_gphy_boot(struct device *dev, unsigned int id, dma_addr_t dev_addr) > return 0; > } > > -/* reset a io domain for u micro seconds */ > -void ltq_reset_once(unsigned int module, ulong u) > -{ > - ltq_rcu_w32(ltq_rcu_r32(RCU_RST_REQ) | module, RCU_RST_REQ); > - udelay(u); > - ltq_rcu_w32(ltq_rcu_r32(RCU_RST_REQ) & ~module, RCU_RST_REQ); > -} > - > -static int ltq_assert_device(struct reset_controller_dev *rcdev, > - unsigned long id) > -{ > - u32 val; > - > - if (id < 8) > - return -1; > - > - val = ltq_rcu_r32(RCU_RST_REQ); > - val |= BIT(id); > - ltq_rcu_w32(val, RCU_RST_REQ); > - > - return 0; > -} > - > -static int ltq_deassert_device(struct reset_controller_dev *rcdev, > - unsigned long id) > -{ > - u32 val; > - > - if (id < 8) > - return -1; > - > - val = ltq_rcu_r32(RCU_RST_REQ); > - val &= ~BIT(id); > - ltq_rcu_w32(val, RCU_RST_REQ); > - > - return 0; > -} > - > -static int ltq_reset_device(struct reset_controller_dev *rcdev, > - unsigned long id) > -{ > - ltq_assert_device(rcdev, id); > - return ltq_deassert_device(rcdev, id); > -} > - > -static const struct reset_control_ops reset_ops = { > - .reset = ltq_reset_device, > - .assert = ltq_assert_device, > - .deassert = ltq_deassert_device, > -}; > - > -static struct reset_controller_dev reset_dev = { > - .ops = &reset_ops, > - .owner = THIS_MODULE, > - .nr_resets = 32, > - .of_reset_n_cells = 1, > -}; > - > -void ltq_rst_init(void) > -{ > - reset_dev.of_node = of_find_compatible_node(NULL, NULL, > - "lantiq,xway-reset"); > - if (!reset_dev.of_node) > - pr_err("Failed to find reset controller node"); > - else > - reset_controller_register(&reset_dev); > -} > - > static void ltq_machine_restart(char *command) > { > u32 val = ltq_rcu_r32(RCU_RST_REQ); > diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig > index f4cdfe94b9ec..8962ba44248c 100644 > --- a/drivers/reset/Kconfig > +++ b/drivers/reset/Kconfig > @@ -27,6 +27,12 @@ config RESET_BERLIN > help > This enables the reset controller driver for Marvell Berlin SoCs. > > +config RESET_LANTIQ_RCU > + bool "Lantiq XWAY Reset Driver" if COMPILE_TEST > + default SOC_TYPE_XWAY > + help > + This enables the reset controller driver for Lantiq / Intel XWAY SoCs. > + > config RESET_LPC18XX > bool "LPC18xx/43xx Reset Driver" if COMPILE_TEST > default ARCH_LPC18XX > diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile > index 2cd3f6c45165..97b0a844b849 100644 > --- a/drivers/reset/Makefile > +++ b/drivers/reset/Makefile > @@ -4,6 +4,7 @@ obj-$(CONFIG_ARCH_STI) += sti/ > obj-$(CONFIG_ARCH_TEGRA) += tegra/ > obj-$(CONFIG_RESET_ATH79) += reset-ath79.o > obj-$(CONFIG_RESET_BERLIN) += reset-berlin.o > +obj-$(CONFIG_RESET_LANTIQ_RCU) += reset-lantiq-rcu.o > obj-$(CONFIG_RESET_LPC18XX) += reset-lpc18xx.o > obj-$(CONFIG_RESET_MESON) += reset-meson.o > obj-$(CONFIG_RESET_OXNAS) += reset-oxnas.o > diff --git a/drivers/reset/reset-lantiq-rcu.c b/drivers/reset/reset-lantiq-rcu.c > new file mode 100644 > index 000000000000..6178112ca5b4 > --- /dev/null > +++ b/drivers/reset/reset-lantiq-rcu.c > @@ -0,0 +1,231 @@ > +/* > + * 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. > + * > + * Copyright (C) 2010 John Crispin <blogic@xxxxxxxxxxx> > + * Copyright (C) 2013-2015 Lantiq Beteiligungs-GmbH & Co.KG > + * Copyright (C) 2016 Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx> > + * Copyright (C) 2017 Hauke Mehrtens <hauke@xxxxxxxxxx> > + */ > + > +#include <linux/mfd/syscon.h> > +#include <linux/module.h> > +#include <linux/regmap.h> > +#include <linux/reset-controller.h> > +#include <linux/of_platform.h> > + > +#define LANTIQ_RCU_RESET_TIMEOUT 1000000 > + > +struct lantiq_rcu_reset_translation { > + int request; > + int status; > +}; > + > +struct lantiq_rcu_reset_priv { > + struct reset_controller_dev rcdev; > + struct device *dev; > + struct regmap *regmap; > + u32 reset_offset; > + u32 status_offset; > + int trans_number; > + struct lantiq_rcu_reset_translation *trans; > +}; > + > +static struct lantiq_rcu_reset_priv *to_lantiq_rcu_reset_priv( > + struct reset_controller_dev *rcdev) > +{ > + return container_of(rcdev, struct lantiq_rcu_reset_priv, rcdev); > +} > + > +static int lantiq_rcu_reset_status(struct reset_controller_dev *rcdev, > + unsigned long id) > +{ > + struct lantiq_rcu_reset_priv *priv = to_lantiq_rcu_reset_priv(rcdev); > + u32 val; > + int ret, i; > + > + if (id >= rcdev->nr_resets) > + return -EINVAL; > + > + for (i = 0; i < priv->trans_number; i++) { > + if (id == priv->trans[i].request) { > + id = priv->trans[i].status; > + break; > + } > + } > + > + ret = regmap_read(priv->regmap, priv->status_offset, &val); > + if (ret) > + return ret; > + > + return !!(val & BIT(id)); > +} > + > +static int lantiq_rcu_reset_update(struct reset_controller_dev *rcdev, > + unsigned long id, bool assert) > +{ > + struct lantiq_rcu_reset_priv *priv = to_lantiq_rcu_reset_priv(rcdev); > + u32 val; > + int ret, retry = LANTIQ_RCU_RESET_TIMEOUT; > + > + if (id >= rcdev->nr_resets) > + return -EINVAL; > + > + if (assert) > + val = BIT(id); > + else > + val = 0; > + > + ret = regmap_update_bits(priv->regmap, priv->reset_offset, BIT(id), > + val); > + if (ret) { > + dev_err(priv->dev, "Failed to set reset bit %lu\n", id); > + return ret; > + } > + > + do {} while (--retry && lantiq_rcu_reset_status(rcdev, id) != assert); > + if (!retry) { > + dev_err(priv->dev, "Failed to %s bit %lu\n", > + assert ? "assert" : "deassert", id); > + return -EIO; > + } > + > + return 0; > +} > + > +static int lantiq_rcu_reset_assert(struct reset_controller_dev *rcdev, > + unsigned long id) > +{ > + return lantiq_rcu_reset_update(rcdev, id, true); > +} > + > +static int lantiq_rcu_reset_deassert(struct reset_controller_dev *rcdev, > + unsigned long id) > +{ > + return lantiq_rcu_reset_update(rcdev, id, false); > +} > + > +static int lantiq_rcu_reset_reset(struct reset_controller_dev *rcdev, > + unsigned long id) > +{ > + int ret; > + > + ret = lantiq_rcu_reset_assert(rcdev, id); > + if (ret) > + return ret; > + > + return lantiq_rcu_reset_deassert(rcdev, id); > +} > + > +static struct reset_control_ops lantiq_rcu_reset_ops = { > + .assert = lantiq_rcu_reset_assert, > + .deassert = lantiq_rcu_reset_deassert, > + .status = lantiq_rcu_reset_status, > + .reset = lantiq_rcu_reset_reset, > +}; > + > +static int lantiq_rcu_reset_of_probe(struct platform_device *pdev, > + struct lantiq_rcu_reset_priv *priv) > +{ > + struct device_node *np = pdev->dev.of_node; > + int cnt, i, ret; > + > + priv->regmap = syscon_regmap_lookup_by_phandle(np, > + "lantiq,rcu-syscon"); > + if (IS_ERR(priv->regmap)) { > + dev_err(&pdev->dev, "Failed to lookup RCU regmap\n"); > + return PTR_ERR(priv->regmap); > + } > + > + if (of_property_read_u32_index(np, "lantiq,rcu-syscon", 1, > + &priv->reset_offset)) { > + dev_err(&pdev->dev, "Failed to get RCU reset offset\n"); > + return -EINVAL; > + } > + > + if (of_property_read_u32_index(np, "lantiq,rcu-syscon", 2, > + &priv->status_offset)) { > + dev_err(&pdev->dev, "Failed to get RCU status offset\n"); > + return -EINVAL; > + } > + > + cnt = of_property_count_elems_of_size(np, "reset-request", sizeof(u32)); > + if (cnt <= 0) > + return 0; > + > + priv->trans = devm_kmalloc_array(&pdev->dev, cnt, sizeof(*priv->trans), > + GFP_KERNEL); > + if (!priv->trans) > + return -ENOMEM; > + > + for (i = 0; i < cnt; i++) { > + ret = of_property_read_u32_index(np, "reset-request", i, > + &priv->trans[i].request); > + if (ret) { > + dev_err(&pdev->dev, > + "Failed to get reset-request at index %i\n", > + i); > + return ret; > + } > + ret = of_property_read_u32_index(np, "reset-status", i, > + &priv->trans[i].status); > + if (ret) { > + dev_err(&pdev->dev, > + "Failed to get reset-status at index %i\n", > + i); > + return ret; > + } > + } > + priv->trans_number = cnt; > + > + return 0; > +} > + > +static int lantiq_rcu_reset_probe(struct platform_device *pdev) > +{ > + struct lantiq_rcu_reset_priv *priv; > + int err; > + > + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); > + if (!priv) > + return -ENOMEM; > + > + priv->dev = &pdev->dev; > + platform_set_drvdata(pdev, priv); > + > + err = lantiq_rcu_reset_of_probe(pdev, priv); > + if (err) > + return err; > + > + priv->rcdev.ops = &lantiq_rcu_reset_ops; > + priv->rcdev.owner = THIS_MODULE; > + priv->rcdev.of_node = pdev->dev.of_node; > + priv->rcdev.of_reset_n_cells = 1; > + priv->rcdev.nr_resets = 32; > + > + err = reset_controller_register(&priv->rcdev); > + if (err) > + return err; > + > + return 0; > +} > + > +static const struct of_device_id lantiq_rcu_reset_dt_ids[] = { > + { .compatible = "lantiq,rcu-reset", }, > + { }, > +}; > +MODULE_DEVICE_TABLE(of, lantiq_rcu_reset_dt_ids); > + > +static struct platform_driver lantiq_rcu_reset_driver = { > + .probe = lantiq_rcu_reset_probe, > + .driver = { > + .name = "lantiq-rcu-reset", > + .of_match_table = lantiq_rcu_reset_dt_ids, > + }, > +}; > +module_platform_driver(lantiq_rcu_reset_driver); > + > +MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx>"); > +MODULE_DESCRIPTION("Lantiq XWAY RCU Reset Controller Driver"); > +MODULE_LICENSE("GPL"); > -- > 2.11.0 > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html