linux/drivers/reset/reset-socfpga.c
Rojhalat Ibrahim d518d9cab1 reset-socfpga: Fix nr_resets property
The SoC-FPGA reset controller driver defines NR_BANKS as 4 and uses that define
for two unrelated purposes. It is used
1. as an increment for reset line banks which are 32-bit registers with 4-byte
aligned addresses.
2. as the total number of reset line banks which together with the number of
resets per bank (32) limits the total number of useable resets to 128 and the
highest useable reset ID to 127.

This is clearly wrong as there are resets with higher IDs than 127 defined in
include/dt-bindings/reset/altr,rst-mgr.h and altr,rst-mgr-a10.h.

The patch introduces a new define BANK_INCREMENT for calculating the register
addresses as before and increases NR_BANKS to 8 for useable reset IDs up to 255.

Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
2017-03-08 09:36:45 +01:00

155 lines
4.0 KiB
C

/*
* Socfpga Reset Controller Driver
*
* Copyright 2014 Steffen Trumtrar <s.trumtrar@pengutronix.de>
*
* based on
* Allwinner SoCs Reset Controller driver
*
* Copyright 2013 Maxime Ripard
*
* Maxime Ripard <maxime.ripard@free-electrons.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/err.h>
#include <linux/io.h>
#include <linux/init.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/reset-controller.h>
#include <linux/spinlock.h>
#include <linux/types.h>
#define BANK_INCREMENT 4
#define NR_BANKS 8
struct socfpga_reset_data {
spinlock_t lock;
void __iomem *membase;
struct reset_controller_dev rcdev;
};
static int socfpga_reset_assert(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct socfpga_reset_data *data = container_of(rcdev,
struct socfpga_reset_data,
rcdev);
int bank = id / BITS_PER_LONG;
int offset = id % BITS_PER_LONG;
unsigned long flags;
u32 reg;
spin_lock_irqsave(&data->lock, flags);
reg = readl(data->membase + (bank * BANK_INCREMENT));
writel(reg | BIT(offset), data->membase + (bank * BANK_INCREMENT));
spin_unlock_irqrestore(&data->lock, flags);
return 0;
}
static int socfpga_reset_deassert(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct socfpga_reset_data *data = container_of(rcdev,
struct socfpga_reset_data,
rcdev);
int bank = id / BITS_PER_LONG;
int offset = id % BITS_PER_LONG;
unsigned long flags;
u32 reg;
spin_lock_irqsave(&data->lock, flags);
reg = readl(data->membase + (bank * BANK_INCREMENT));
writel(reg & ~BIT(offset), data->membase + (bank * BANK_INCREMENT));
spin_unlock_irqrestore(&data->lock, flags);
return 0;
}
static int socfpga_reset_status(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct socfpga_reset_data *data = container_of(rcdev,
struct socfpga_reset_data, rcdev);
int bank = id / BITS_PER_LONG;
int offset = id % BITS_PER_LONG;
u32 reg;
reg = readl(data->membase + (bank * BANK_INCREMENT));
return !(reg & BIT(offset));
}
static const struct reset_control_ops socfpga_reset_ops = {
.assert = socfpga_reset_assert,
.deassert = socfpga_reset_deassert,
.status = socfpga_reset_status,
};
static int socfpga_reset_probe(struct platform_device *pdev)
{
struct socfpga_reset_data *data;
struct resource *res;
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
u32 modrst_offset;
/*
* The binding was mainlined without the required property.
* Do not continue, when we encounter an old DT.
*/
if (!of_find_property(pdev->dev.of_node, "#reset-cells", NULL)) {
dev_err(&pdev->dev, "%s missing #reset-cells property\n",
pdev->dev.of_node->full_name);
return -EINVAL;
}
data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
data->membase = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(data->membase))
return PTR_ERR(data->membase);
if (of_property_read_u32(np, "altr,modrst-offset", &modrst_offset)) {
dev_warn(dev, "missing altr,modrst-offset property, assuming 0x10!\n");
modrst_offset = 0x10;
}
data->membase += modrst_offset;
spin_lock_init(&data->lock);
data->rcdev.owner = THIS_MODULE;
data->rcdev.nr_resets = NR_BANKS * BITS_PER_LONG;
data->rcdev.ops = &socfpga_reset_ops;
data->rcdev.of_node = pdev->dev.of_node;
return devm_reset_controller_register(dev, &data->rcdev);
}
static const struct of_device_id socfpga_reset_dt_ids[] = {
{ .compatible = "altr,rst-mgr", },
{ /* sentinel */ },
};
static struct platform_driver socfpga_reset_driver = {
.probe = socfpga_reset_probe,
.driver = {
.name = "socfpga-reset",
.of_match_table = socfpga_reset_dt_ids,
},
};
builtin_platform_driver(socfpga_reset_driver);