lkml.org 
[lkml]   [2022]   [Jun]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH v5 15/15] reset: elbasr: Add AMD Pensando Elba SR Reset Controller
    Date
    From: Brad Larson <blarson@amd.com>

    This patch adds the reset controller functionality for the
    AMD Pensando Elba System Resource Chip.

    Signed-off-by: Brad Larson <blarson@amd.com>
    ---
    drivers/reset/Kconfig | 9 ++
    drivers/reset/Makefile | 1 +
    drivers/reset/reset-elbasr.c | 94 +++++++++++++++++++
    .../reset/amd,pensando-elba-reset.h | 11 +++
    4 files changed, 115 insertions(+)
    create mode 100644 drivers/reset/reset-elbasr.c
    create mode 100644 include/dt-bindings/reset/amd,pensando-elba-reset.h

    diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig
    index 93c8d07ee328..13f5a8ca0f03 100644
    --- a/drivers/reset/Kconfig
    +++ b/drivers/reset/Kconfig
    @@ -66,6 +66,15 @@ config RESET_BRCMSTB_RESCAL
    This enables the RESCAL reset controller for SATA, PCIe0, or PCIe1 on
    BCM7216.

    +config RESET_ELBASR
    + tristate "Pensando Elba System Resource reset controller"
    + depends on MFD_PENSANDO_ELBASR || COMPILE_TEST
    + help
    + This option enables support for the external reset functions
    + on the Pensando Elba System Resource Chip. Reset control
    + of peripherals is accessed over SPI to the system resource
    + chip device registers using CS0.
    +
    config RESET_HSDK
    bool "Synopsys HSDK Reset Driver"
    depends on HAS_IOMEM
    diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile
    index a80a9c4008a7..c0fe12b9950e 100644
    --- a/drivers/reset/Makefile
    +++ b/drivers/reset/Makefile
    @@ -10,6 +10,7 @@ obj-$(CONFIG_RESET_BCM6345) += reset-bcm6345.o
    obj-$(CONFIG_RESET_BERLIN) += reset-berlin.o
    obj-$(CONFIG_RESET_BRCMSTB) += reset-brcmstb.o
    obj-$(CONFIG_RESET_BRCMSTB_RESCAL) += reset-brcmstb-rescal.o
    +obj-$(CONFIG_RESET_ELBASR) += reset-elbasr.o
    obj-$(CONFIG_RESET_HSDK) += reset-hsdk.o
    obj-$(CONFIG_RESET_IMX7) += reset-imx7.o
    obj-$(CONFIG_RESET_INTEL_GW) += reset-intel-gw.o
    diff --git a/drivers/reset/reset-elbasr.c b/drivers/reset/reset-elbasr.c
    new file mode 100644
    index 000000000000..6e429cb11466
    --- /dev/null
    +++ b/drivers/reset/reset-elbasr.c
    @@ -0,0 +1,94 @@
    +// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
    +/*
    + * Copyright (c) 2022 AMD Pensando
    + */
    +
    +#include <linux/mfd/pensando-elbasr.h>
    +#include <linux/platform_device.h>
    +#include <linux/reset-controller.h>
    +#include <linux/regmap.h>
    +#include <linux/err.h>
    +#include <linux/of.h>
    +
    +#include <dt-bindings/reset/amd,pensando-elba-reset.h>
    +
    +struct elbasr_reset {
    + struct reset_controller_dev rcdev;
    + struct regmap *regmap;
    +};
    +
    +static inline struct elbasr_reset *to_elbasr_rst(struct reset_controller_dev *rc)
    +{
    + return container_of(rc, struct elbasr_reset, rcdev);
    +}
    +
    +static inline int elbasr_reset_shift(unsigned long id)
    +{
    + switch (id) {
    + case EMMC_HW_RESET:
    + return 6;
    + default:
    + return -EINVAL;
    + }
    +}
    +
    +static int elbasr_reset_assert(struct reset_controller_dev *rcdev,
    + unsigned long id)
    +{
    + struct elbasr_reset *elbar = to_elbasr_rst(rcdev);
    + u32 mask = 1 << elbasr_reset_shift(id);
    +
    + return regmap_update_bits(elbar->regmap, ELBASR_CTRL0_REG, mask, mask);
    +}
    +
    +static int elbasr_reset_deassert(struct reset_controller_dev *rcdev,
    + unsigned long id)
    +{
    + struct elbasr_reset *elbar = to_elbasr_rst(rcdev);
    + u32 mask = 1 << elbasr_reset_shift(id);
    +
    + return regmap_update_bits(elbar->regmap, ELBASR_CTRL0_REG, mask, 0);
    +}
    +
    +static const struct reset_control_ops elbasr_reset_ops = {
    + .assert = elbasr_reset_assert,
    + .deassert = elbasr_reset_deassert,
    +};
    +
    +static int elbasr_reset_probe(struct platform_device *pdev)
    +{
    + struct elbasr_data *elbasr = dev_get_drvdata(pdev->dev.parent);
    + struct elbasr_reset *elbar;
    + int ret;
    +
    + elbar = devm_kzalloc(&pdev->dev, sizeof(struct elbasr_reset),
    + GFP_KERNEL);
    + if (!elbar)
    + return -ENOMEM;
    +
    + elbar->rcdev.owner = THIS_MODULE;
    + elbar->rcdev.nr_resets = ELBASR_NR_RESETS;
    + elbar->rcdev.ops = &elbasr_reset_ops;
    + elbar->rcdev.of_node = pdev->dev.of_node;
    + elbar->regmap = elbasr->elbasr_regs;
    +
    + platform_set_drvdata(pdev, elbar);
    +
    + ret = devm_reset_controller_register(&pdev->dev, &elbar->rcdev);
    +
    + return ret;
    +}
    +
    +static const struct of_device_id elba_reset_dt_match[] = {
    + { .compatible = "amd,pensando-elbasr-reset", },
    + { /* sentinel */ },
    +};
    +
    +static struct platform_driver elbasr_reset_driver = {
    + .probe = elbasr_reset_probe,
    + .driver = {
    + .name = "pensando_elbasr_reset",
    + .of_match_table = elba_reset_dt_match,
    + },
    +};
    +builtin_platform_driver(elbasr_reset_driver);
    diff --git a/include/dt-bindings/reset/amd,pensando-elba-reset.h b/include/dt-bindings/reset/amd,pensando-elba-reset.h
    new file mode 100644
    index 000000000000..68d69a98e750
    --- /dev/null
    +++ b/include/dt-bindings/reset/amd,pensando-elba-reset.h
    @@ -0,0 +1,11 @@
    +/* SPDX-License-Identifier: (GPL-2.0+ OR MIT) */
    +/*
    + * Copyright (c) 2022, AMD Pensando
    + */
    +
    +#ifndef _DT_BINDINGS_RESET_AMD_PENSANDO_ELBA_RESET_H
    +#define _DT_BINDINGS_RESET_AMD_PENSANDO_ELBA_RESET_H
    +
    +#define EMMC_HW_RESET 0
    +
    +#endif
    --
    2.17.1
    \
     
     \ /
      Last update: 2022-06-13 22:50    [W:2.682 / U:0.004 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site