mirror of
https://github.com/brain-hackers/u-boot-brain
synced 2024-08-31 06:18:51 +09:00
![Simon Glass](/assets/img/avatar_default.png)
This construct is quite long-winded. In earlier days it made some sense since auto-allocation was a strange concept. But with driver model now used pretty universally, we can shorten this to 'auto'. This reduces verbosity and makes it easier to read. Coincidentally it also ensures that every declaration is on one line, thus making dtoc's job easier. Signed-off-by: Simon Glass <sjg@chromium.org>
211 lines
5.8 KiB
C
211 lines
5.8 KiB
C
// SPDX-License-Identifier: GPL-2.0+
|
|
/*
|
|
* Texas Instruments System Control Interface (TI SCI) reset driver
|
|
*
|
|
* Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com/
|
|
* Andreas Dannenberg <dannenberg@ti.com>
|
|
*
|
|
* Loosely based on Linux kernel reset-ti-sci.c...
|
|
*/
|
|
|
|
#include <common.h>
|
|
#include <dm.h>
|
|
#include <errno.h>
|
|
#include <log.h>
|
|
#include <malloc.h>
|
|
#include <reset-uclass.h>
|
|
#include <dm/device_compat.h>
|
|
#include <linux/err.h>
|
|
#include <linux/soc/ti/ti_sci_protocol.h>
|
|
|
|
/**
|
|
* struct ti_sci_reset_data - reset controller information structure
|
|
* @sci: TI SCI handle used for communication with system controller
|
|
*/
|
|
struct ti_sci_reset_data {
|
|
const struct ti_sci_handle *sci;
|
|
};
|
|
|
|
static int ti_sci_reset_probe(struct udevice *dev)
|
|
{
|
|
struct ti_sci_reset_data *data = dev_get_priv(dev);
|
|
|
|
debug("%s(dev=%p)\n", __func__, dev);
|
|
|
|
if (!data)
|
|
return -ENOMEM;
|
|
|
|
/* Store handle for communication with the system controller */
|
|
data->sci = ti_sci_get_handle(dev);
|
|
if (IS_ERR(data->sci))
|
|
return PTR_ERR(data->sci);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ti_sci_reset_of_xlate(struct reset_ctl *rst,
|
|
struct ofnode_phandle_args *args)
|
|
{
|
|
debug("%s(rst=%p, args_count=%d)\n", __func__, rst, args->args_count);
|
|
|
|
if (args->args_count != 2) {
|
|
debug("Invalid args_count: %d\n", args->args_count);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/*
|
|
* On TI SCI-based devices, the reset provider id field is used as a
|
|
* device ID, and the data field is used as the associated reset mask.
|
|
*/
|
|
rst->id = args->args[0];
|
|
rst->data = args->args[1];
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ti_sci_reset_request(struct reset_ctl *rst)
|
|
{
|
|
debug("%s(rst=%p)\n", __func__, rst);
|
|
return 0;
|
|
}
|
|
|
|
static int ti_sci_reset_free(struct reset_ctl *rst)
|
|
{
|
|
debug("%s(rst=%p)\n", __func__, rst);
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* ti_sci_reset_set() - program a device's reset
|
|
* @rst: Handle to a single reset signal
|
|
* @assert: boolean flag to indicate assert or deassert
|
|
*
|
|
* This is a common internal function used to assert or deassert a device's
|
|
* reset using the TI SCI protocol. The device's reset is asserted if the
|
|
* @assert argument is true, or deasserted if @assert argument is false.
|
|
* The mechanism itself is a read-modify-write procedure, the current device
|
|
* reset register is read using a TI SCI device operation, the new value is
|
|
* set or un-set using the reset's mask, and the new reset value written by
|
|
* using another TI SCI device operation.
|
|
*
|
|
* Return: 0 for successful request, else a corresponding error value
|
|
*/
|
|
static int ti_sci_reset_set(struct reset_ctl *rst, bool assert)
|
|
{
|
|
struct ti_sci_reset_data *data = dev_get_priv(rst->dev);
|
|
const struct ti_sci_handle *sci = data->sci;
|
|
const struct ti_sci_dev_ops *dops = &sci->ops.dev_ops;
|
|
u32 reset_state;
|
|
int ret;
|
|
|
|
ret = dops->get_device_resets(sci, rst->id, &reset_state);
|
|
if (ret) {
|
|
dev_err(rst->dev, "%s: get_device_resets failed (%d)\n",
|
|
__func__, ret);
|
|
return ret;
|
|
}
|
|
|
|
if (assert)
|
|
reset_state |= rst->data;
|
|
else
|
|
reset_state &= ~rst->data;
|
|
|
|
ret = dops->set_device_resets(sci, rst->id, reset_state);
|
|
if (ret) {
|
|
dev_err(rst->dev, "%s: set_device_resets failed (%d)\n",
|
|
__func__, ret);
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* ti_sci_reset_assert() - assert device reset
|
|
* @rst: Handle to a single reset signal
|
|
*
|
|
* This function implements the reset driver op to assert a device's reset
|
|
* using the TI SCI protocol. This invokes the function ti_sci_reset_set()
|
|
* with the corresponding parameters as passed in, but with the @assert
|
|
* argument set to true for asserting the reset.
|
|
*
|
|
* Return: 0 for successful request, else a corresponding error value
|
|
*/
|
|
static int ti_sci_reset_assert(struct reset_ctl *rst)
|
|
{
|
|
debug("%s(rst=%p)\n", __func__, rst);
|
|
return ti_sci_reset_set(rst, true);
|
|
}
|
|
|
|
/**
|
|
* ti_sci_reset_deassert() - deassert device reset
|
|
* @rst: Handle to a single reset signal
|
|
*
|
|
* This function implements the reset driver op to deassert a device's reset
|
|
* using the TI SCI protocol. This invokes the function ti_sci_reset_set()
|
|
* with the corresponding parameters as passed in, but with the @assert
|
|
* argument set to false for deasserting the reset.
|
|
*
|
|
* Return: 0 for successful request, else a corresponding error value
|
|
*/
|
|
static int ti_sci_reset_deassert(struct reset_ctl *rst)
|
|
{
|
|
debug("%s(rst=%p)\n", __func__, rst);
|
|
return ti_sci_reset_set(rst, false);
|
|
}
|
|
|
|
/**
|
|
* ti_sci_reset_status() - check device reset status
|
|
* @rst: Handle to a single reset signal
|
|
*
|
|
* This function implements the reset driver op to return the status of a
|
|
* device's reset using the TI SCI protocol. The reset register value is read
|
|
* by invoking the TI SCI device operation .get_device_resets(), and the
|
|
* status of the specific reset is extracted and returned using this reset's
|
|
* reset mask.
|
|
*
|
|
* Return: 0 if reset is deasserted, or a non-zero value if reset is asserted
|
|
*/
|
|
static int ti_sci_reset_status(struct reset_ctl *rst)
|
|
{
|
|
struct ti_sci_reset_data *data = dev_get_priv(rst->dev);
|
|
const struct ti_sci_handle *sci = data->sci;
|
|
const struct ti_sci_dev_ops *dops = &sci->ops.dev_ops;
|
|
u32 reset_state;
|
|
int ret;
|
|
|
|
debug("%s(rst=%p)\n", __func__, rst);
|
|
|
|
ret = dops->get_device_resets(sci, rst->id, &reset_state);
|
|
if (ret) {
|
|
dev_err(rst->dev, "%s: get_device_resets failed (%d)\n",
|
|
__func__, ret);
|
|
return ret;
|
|
}
|
|
|
|
return reset_state & rst->data;
|
|
}
|
|
|
|
static const struct udevice_id ti_sci_reset_of_match[] = {
|
|
{ .compatible = "ti,sci-reset", },
|
|
{ /* sentinel */ },
|
|
};
|
|
|
|
static struct reset_ops ti_sci_reset_ops = {
|
|
.of_xlate = ti_sci_reset_of_xlate,
|
|
.request = ti_sci_reset_request,
|
|
.rfree = ti_sci_reset_free,
|
|
.rst_assert = ti_sci_reset_assert,
|
|
.rst_deassert = ti_sci_reset_deassert,
|
|
.rst_status = ti_sci_reset_status,
|
|
};
|
|
|
|
U_BOOT_DRIVER(ti_sci_reset) = {
|
|
.name = "ti-sci-reset",
|
|
.id = UCLASS_RESET,
|
|
.of_match = ti_sci_reset_of_match,
|
|
.probe = ti_sci_reset_probe,
|
|
.priv_auto = sizeof(struct ti_sci_reset_data),
|
|
.ops = &ti_sci_reset_ops,
|
|
};
|