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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
| commit | 4352b8aee98005853aa63f57d6377282de17a33f (patch) | |
| tree | 27614d7a9ef05c32d089004e104364ce42324837 /drivers/reset/reset-mpfs.c | |
| download | linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip | |
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni:
"A new driver this cycle, for the AMD AXI I3C controller.
There are also new features such as IBI wakeup support, SETAASA device
discovery and ACPI support for the the DAA methods, meaning we can now
communicate with the SPD devices on DDR5 modules.
New driver:
- AMD AXI I3C master controller
Subsystem:
- I3C Common Command Code (CCC) handling improvements, especially
around GET CCCs
- SETAASA device discovery support
- ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
well as I2C devices on I3C bus
- IBI-based wakeup support
Drivers:
- dw: SETAASA support
- mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
controller support, PIO queue management support for HCI v1.2
- renesas: improve suspend to RAM support, add runtime PM support"
* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
i3c: dw: reduce do_daa time if there's no client
i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
i3c: dw: rename "pclk" to "apb" to match dt-binding
i3c: dw: make struct dw_i3c_cmd smaller
i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
i3c: renesas: Don't register devices when ENTDAA times out
i3c: master: dw-i3c-master: fix OD timing for first broadcast
i3c: mipi-i3c-hci: Advertise IBI wakeup capability
i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
i3c: master: Reject IBI requests from non-IBI-capable devices
i3c: master: Add helper to query bus wakeup requirements
i3c: master: Report wakeup events for IBIs
i3c: master: Support IBI-based wakeup capability
i3c: master: Fix potential UAF in i3c_device_match()
i3c: master: Fix potential UAF in i3c_device_uevent()
i3c: Make dev->desc locking assumptions explicit
i3c: master: Fix use-after-free of master->this
...
Diffstat (limited to 'drivers/reset/reset-mpfs.c')
| -rw-r--r-- | drivers/reset/reset-mpfs.c | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/drivers/reset/reset-mpfs.c b/drivers/reset/reset-mpfs.c new file mode 100644 index 000000000..8ffcc54ee --- /dev/null +++ b/drivers/reset/reset-mpfs.c @@ -0,0 +1,207 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * PolarFire SoC (MPFS) Peripheral Clock Reset Controller + * + * Author: Conor Dooley <conor.dooley@microchip.com> + * Copyright (c) 2022 Microchip Technology Inc. and its subsidiaries. + * + */ +#include <linux/auxiliary_bus.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/reset-controller.h> +#include <linux/slab.h> +#include <dt-bindings/clock/microchip,mpfs-clock.h> +#include <soc/microchip/mpfs.h> + +/* + * The ENVM reset is the lowest bit in the register & I am using the CLK_FOO + * defines in the dt to make things easier to configure - so this is accounting + * for the offset of 3 there. + */ +#define MPFS_PERIPH_OFFSET CLK_ENVM +#define MPFS_NUM_RESETS 30u +#define MPFS_SLEEP_MIN_US 100 +#define MPFS_SLEEP_MAX_US 200 + +#define REG_SUBBLK_RESET_CR 0x88u + +struct mpfs_reset { + struct regmap *regmap; + struct reset_controller_dev rcdev; +}; + +static inline struct mpfs_reset *to_mpfs_reset(struct reset_controller_dev *rcdev) +{ + return container_of(rcdev, struct mpfs_reset, rcdev); +} + +/* + * Peripheral clock resets + */ +static int mpfs_assert(struct reset_controller_dev *rcdev, unsigned long id) +{ + struct mpfs_reset *rst = to_mpfs_reset(rcdev); + + return regmap_set_bits(rst->regmap, REG_SUBBLK_RESET_CR, BIT(id)); + +} + +static int mpfs_deassert(struct reset_controller_dev *rcdev, unsigned long id) +{ + struct mpfs_reset *rst = to_mpfs_reset(rcdev); + + return regmap_clear_bits(rst->regmap, REG_SUBBLK_RESET_CR, BIT(id)); + +} + +static int mpfs_status(struct reset_controller_dev *rcdev, unsigned long id) +{ + struct mpfs_reset *rst = to_mpfs_reset(rcdev); + u32 reg; + + regmap_read(rst->regmap, REG_SUBBLK_RESET_CR, ®); + + /* + * It is safe to return here as MPFS_NUM_RESETS makes sure the sign bit + * is never hit. + */ + return (reg & BIT(id)); +} + +static int mpfs_reset(struct reset_controller_dev *rcdev, unsigned long id) +{ + mpfs_assert(rcdev, id); + + usleep_range(MPFS_SLEEP_MIN_US, MPFS_SLEEP_MAX_US); + + mpfs_deassert(rcdev, id); + + return 0; +} + +static const struct reset_control_ops mpfs_reset_ops = { + .reset = mpfs_reset, + .assert = mpfs_assert, + .deassert = mpfs_deassert, + .status = mpfs_status, +}; + +static int mpfs_reset_xlate(struct reset_controller_dev *rcdev, + const struct of_phandle_args *reset_spec) +{ + unsigned int index = reset_spec->args[0]; + + /* + * CLK_RESERVED does not map to a clock, but it does map to a reset, + * so it has to be accounted for here. It is the reset for the fabric, + * so if this reset gets called - do not reset it. + */ + if (index == CLK_RESERVED) { + dev_err(rcdev->dev, "Resetting the fabric is not supported\n"); + return -EINVAL; + } + + if (index < MPFS_PERIPH_OFFSET || index >= (MPFS_PERIPH_OFFSET + rcdev->nr_resets)) { + dev_err(rcdev->dev, "Invalid reset index %u\n", index); + return -EINVAL; + } + + return index - MPFS_PERIPH_OFFSET; +} + +static int mpfs_reset_mfd_probe(struct platform_device *pdev) +{ + struct reset_controller_dev *rcdev; + struct device *dev = &pdev->dev; + struct mpfs_reset *rst; + + rst = devm_kzalloc(dev, sizeof(*rst), GFP_KERNEL); + if (!rst) + return -ENOMEM; + + rcdev = &rst->rcdev; + rcdev->dev = dev; + rcdev->ops = &mpfs_reset_ops; + + rcdev->of_node = pdev->dev.parent->of_node; + rcdev->of_reset_n_cells = 1; + rcdev->of_xlate = mpfs_reset_xlate; + rcdev->nr_resets = MPFS_NUM_RESETS; + + rst->regmap = device_node_to_regmap(pdev->dev.parent->of_node); + if (IS_ERR(rst->regmap)) + return dev_err_probe(dev, PTR_ERR(rst->regmap), + "Failed to find syscon regmap\n"); + + return devm_reset_controller_register(dev, rcdev); +} + +static struct platform_driver mpfs_reset_mfd_driver = { + .probe = mpfs_reset_mfd_probe, + .driver = { + .name = "mpfs-reset", + }, +}; +module_platform_driver(mpfs_reset_mfd_driver); + +static int mpfs_reset_adev_probe(struct auxiliary_device *adev, + const struct auxiliary_device_id *id) +{ + struct reset_controller_dev *rcdev; + struct device *dev = &adev->dev; + struct mpfs_reset *rst; + + rst = devm_kzalloc(dev, sizeof(*rst), GFP_KERNEL); + if (!rst) + return -ENOMEM; + + rst->regmap = (struct regmap *)adev->dev.platform_data; + + rcdev = &rst->rcdev; + rcdev->dev = dev; + rcdev->ops = &mpfs_reset_ops; + + rcdev->of_node = dev->parent->of_node; + rcdev->of_reset_n_cells = 1; + rcdev->of_xlate = mpfs_reset_xlate; + rcdev->nr_resets = MPFS_NUM_RESETS; + + return devm_reset_controller_register(dev, rcdev); +} + +int mpfs_reset_controller_register(struct device *clk_dev, struct regmap *map) +{ + struct auxiliary_device *adev; + + adev = devm_auxiliary_device_create(clk_dev, "reset-mpfs", (void *)map); + if (!adev) + return -ENODEV; + + return 0; +} +EXPORT_SYMBOL_NS_GPL(mpfs_reset_controller_register, "MCHP_CLK_MPFS"); + +static const struct auxiliary_device_id mpfs_reset_ids[] = { + { + .name = "reset_mpfs.reset-mpfs", + }, + { } +}; +MODULE_DEVICE_TABLE(auxiliary, mpfs_reset_ids); + +static struct auxiliary_driver mpfs_reset_aux_driver = { + .probe = mpfs_reset_adev_probe, + .id_table = mpfs_reset_ids, +}; + +module_auxiliary_driver(mpfs_reset_aux_driver); + +MODULE_DESCRIPTION("Microchip PolarFire SoC Reset Driver"); +MODULE_AUTHOR("Conor Dooley <conor.dooley@microchip.com>"); +MODULE_IMPORT_NS("MCHP_CLK_MPFS"); |
