linux/drivers/bus/uniphier-system-bus.c

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 Based on 3 normalized pattern(s): 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 this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details 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 [author] [kishon] [vijay] [abraham] [i] [kishon]@[ti] [com] this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details 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 [author] [graeme] [gregory] [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i] [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema] [hk] [hemahk]@[ti] [com] this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1105 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-27 06:55:06 +00:00
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2015 Masahiro Yamada <yamada.masahiro@socionext.com>
*/
#include <linux/io.h>
#include <linux/log2.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
/* System Bus Controller registers */
#define UNIPHIER_SBC_BASE 0x100 /* base address of bank0 space */
#define UNIPHIER_SBC_BASE_BE BIT(0) /* bank_enable */
#define UNIPHIER_SBC_CTRL0 0x200 /* timing parameter 0 of bank0 */
#define UNIPHIER_SBC_CTRL1 0x204 /* timing parameter 1 of bank0 */
#define UNIPHIER_SBC_CTRL2 0x208 /* timing parameter 2 of bank0 */
#define UNIPHIER_SBC_CTRL3 0x20c /* timing parameter 3 of bank0 */
#define UNIPHIER_SBC_CTRL4 0x300 /* timing parameter 4 of bank0 */
#define UNIPHIER_SBC_STRIDE 0x10 /* register stride to next bank */
#define UNIPHIER_SBC_NR_BANKS 8 /* number of banks (chip select) */
#define UNIPHIER_SBC_BASE_DUMMY 0xffffffff /* data to squash bank 0, 1 */
struct uniphier_system_bus_bank {
u32 base;
u32 end;
};
struct uniphier_system_bus_priv {
struct device *dev;
void __iomem *membase;
struct uniphier_system_bus_bank bank[UNIPHIER_SBC_NR_BANKS];
};
static int uniphier_system_bus_add_bank(struct uniphier_system_bus_priv *priv,
int bank, u32 addr, u64 paddr, u32 size)
{
u64 end, mask;
dev_dbg(priv->dev,
"range found: bank = %d, addr = %08x, paddr = %08llx, size = %08x\n",
bank, addr, paddr, size);
if (bank >= ARRAY_SIZE(priv->bank)) {
dev_err(priv->dev, "unsupported bank number %d\n", bank);
return -EINVAL;
}
if (priv->bank[bank].base || priv->bank[bank].end) {
dev_err(priv->dev,
"range for bank %d has already been specified\n", bank);
return -EINVAL;
}
if (paddr > U32_MAX) {
dev_err(priv->dev, "base address %llx is too high\n", paddr);
return -EINVAL;
}
end = paddr + size;
if (addr > paddr) {
dev_err(priv->dev,
"base %08x cannot be mapped to %08llx of parent\n",
addr, paddr);
return -EINVAL;
}
paddr -= addr;
paddr = round_down(paddr, 0x00020000);
end = round_up(end, 0x00020000);
if (end > U32_MAX) {
dev_err(priv->dev, "end address %08llx is too high\n", end);
return -EINVAL;
}
mask = paddr ^ (end - 1);
mask = roundup_pow_of_two(mask);
paddr = round_down(paddr, mask);
end = round_up(end, mask);
priv->bank[bank].base = paddr;
priv->bank[bank].end = end;
dev_dbg(priv->dev, "range added: bank = %d, addr = %08x, end = %08x\n",
bank, priv->bank[bank].base, priv->bank[bank].end);
return 0;
}
static int uniphier_system_bus_check_overlap(
const struct uniphier_system_bus_priv *priv)
{
int i, j;
for (i = 0; i < ARRAY_SIZE(priv->bank); i++) {
for (j = i + 1; j < ARRAY_SIZE(priv->bank); j++) {
if (priv->bank[i].end > priv->bank[j].base &&
priv->bank[i].base < priv->bank[j].end) {
dev_err(priv->dev,
"region overlap between bank%d and bank%d\n",
i, j);
return -EINVAL;
}
}
}
return 0;
}
static void uniphier_system_bus_check_boot_swap(
struct uniphier_system_bus_priv *priv)
{
void __iomem *base_reg = priv->membase + UNIPHIER_SBC_BASE;
int is_swapped;
is_swapped = !(readl(base_reg) & UNIPHIER_SBC_BASE_BE);
dev_dbg(priv->dev, "Boot Swap: %s\n", is_swapped ? "on" : "off");
/*
* If BOOT_SWAP was asserted on power-on-reset, the CS0 and CS1 are
* swapped. In this case, bank0 and bank1 should be swapped as well.
*/
if (is_swapped)
swap(priv->bank[0], priv->bank[1]);
}
static void uniphier_system_bus_set_reg(
const struct uniphier_system_bus_priv *priv)
{
void __iomem *base_reg = priv->membase + UNIPHIER_SBC_BASE;
u32 base, end, mask, val;
int i;
for (i = 0; i < ARRAY_SIZE(priv->bank); i++) {
base = priv->bank[i].base;
end = priv->bank[i].end;
if (base == end) {
/*
* If SBC_BASE0 or SBC_BASE1 is set to zero, the access
* to anywhere in the system bus space is routed to
* bank 0 (if boot swap if off) or bank 1 (if boot swap
* if on). It means that CPUs cannot get access to
* bank 2 or later. In other words, bank 0/1 cannot
* be disabled even if its bank_enable bits is cleared.
* This seems odd, but it is how this hardware goes.
* As a workaround, dummy data (0xffffffff) should be
* set when the bank 0/1 is unused. As for bank 2 and
* later, they can be simply disable by clearing the
* bank_enable bit.
*/
if (i < 2)
val = UNIPHIER_SBC_BASE_DUMMY;
else
val = 0;
} else {
mask = base ^ (end - 1);
val = base & 0xfffe0000;
val |= (~mask >> 16) & 0xfffe;
val |= UNIPHIER_SBC_BASE_BE;
}
dev_dbg(priv->dev, "SBC_BASE[%d] = 0x%08x\n", i, val);
writel(val, base_reg + UNIPHIER_SBC_STRIDE * i);
}
}
static int uniphier_system_bus_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct uniphier_system_bus_priv *priv;
struct of_range_parser parser;
struct of_range range;
int ret;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->membase = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(priv->membase))
return PTR_ERR(priv->membase);
priv->dev = dev;
ret = of_range_parser_init(&parser, dev->of_node);
if (ret)
return ret;
for_each_of_range(&parser, &range) {
if (range.cpu_addr == OF_BAD_ADDR)
return -EINVAL;
ret = uniphier_system_bus_add_bank(priv,
upper_32_bits(range.bus_addr),
lower_32_bits(range.bus_addr),
range.cpu_addr, range.size);
if (ret)
return ret;
}
ret = uniphier_system_bus_check_overlap(priv);
if (ret)
return ret;
uniphier_system_bus_check_boot_swap(priv);
uniphier_system_bus_set_reg(priv);
platform_set_drvdata(pdev, priv);
/* Now, the bus is configured. Populate platform_devices below it */
return of_platform_default_populate(dev->of_node, NULL, dev);
}
static int __maybe_unused uniphier_system_bus_resume(struct device *dev)
{
uniphier_system_bus_set_reg(dev_get_drvdata(dev));
return 0;
}
static const struct dev_pm_ops uniphier_system_bus_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(NULL, uniphier_system_bus_resume)
};
static const struct of_device_id uniphier_system_bus_match[] = {
{ .compatible = "socionext,uniphier-system-bus" },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, uniphier_system_bus_match);
static struct platform_driver uniphier_system_bus_driver = {
.probe = uniphier_system_bus_probe,
.driver = {
.name = "uniphier-system-bus",
.of_match_table = uniphier_system_bus_match,
.pm = &uniphier_system_bus_pm_ops,
},
};
module_platform_driver(uniphier_system_bus_driver);
MODULE_AUTHOR("Masahiro Yamada <yamada.masahiro@socionext.com>");
MODULE_DESCRIPTION("UniPhier System Bus driver");
MODULE_LICENSE("GPL");