linux/drivers/soc/lantiq/fpi-bus.c

86 lines
2.2 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
*
* Copyright (C) 2011-2015 John Crispin <blogic@phrozen.org>
* Copyright (C) 2015 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
* Copyright (C) 2017 Hauke Mehrtens <hauke@hauke-m.de>
*/
#include <linux/device.h>
#include <linux/err.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/regmap.h>
#include <lantiq_soc.h>
#define XBAR_ALWAYS_LAST 0x430
#define XBAR_FPI_BURST_EN BIT(1)
#define XBAR_AHB_BURST_EN BIT(2)
#define RCU_VR9_BE_AHB1S 0x00000008
static int ltq_fpi_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct resource *res_xbar;
struct regmap *rcu_regmap;
void __iomem *xbar_membase;
u32 rcu_ahb_endianness_reg_offset;
int ret;
res_xbar = platform_get_resource(pdev, IORESOURCE_MEM, 0);
xbar_membase = devm_ioremap_resource(dev, res_xbar);
if (IS_ERR(xbar_membase))
return PTR_ERR(xbar_membase);
/* RCU configuration is optional */
rcu_regmap = syscon_regmap_lookup_by_phandle(np, "lantiq,rcu");
if (IS_ERR(rcu_regmap))
return PTR_ERR(rcu_regmap);
ret = device_property_read_u32(dev, "lantiq,offset-endianness",
&rcu_ahb_endianness_reg_offset);
if (ret) {
dev_err(&pdev->dev, "Failed to get RCU reg offset\n");
return ret;
}
ret = regmap_update_bits(rcu_regmap, rcu_ahb_endianness_reg_offset,
RCU_VR9_BE_AHB1S, RCU_VR9_BE_AHB1S);
if (ret) {
dev_warn(&pdev->dev,
"Failed to configure RCU AHB endianness\n");
return ret;
}
/* disable fpi burst */
ltq_w32_mask(XBAR_FPI_BURST_EN, 0, xbar_membase + XBAR_ALWAYS_LAST);
return of_platform_populate(dev->of_node, NULL, NULL, dev);
}
static const struct of_device_id ltq_fpi_match[] = {
{ .compatible = "lantiq,xrx200-fpi" },
{},
};
MODULE_DEVICE_TABLE(of, ltq_fpi_match);
static struct platform_driver ltq_fpi_driver = {
.probe = ltq_fpi_probe,
.driver = {
.name = "fpi-xway",
.of_match_table = ltq_fpi_match,
},
};
module_platform_driver(ltq_fpi_driver);
MODULE_DESCRIPTION("Lantiq FPI bus driver");
MODULE_LICENSE("GPL");