swh:1:snp:3c665ee4f67729f27f2e40193ab88e7298cf0fef
Tip revision: ce397d215ccd07b8ae3f71db689aedb85d56ab40 authored by Linus Torvalds on 16 June 2018, 23:04:49 UTC
Linux 4.18-rc1
Linux 4.18-rc1
Tip revision: ce397d2
reset-hsdk.c
/*
* Copyright (C) 2017 Synopsys.
*
* Synopsys HSDK Development platform reset driver.
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/reset-controller.h>
#include <linux/slab.h>
#include <linux/types.h>
#define to_hsdk_rst(p) container_of((p), struct hsdk_rst, rcdev)
struct hsdk_rst {
void __iomem *regs_ctl;
void __iomem *regs_rst;
spinlock_t lock;
struct reset_controller_dev rcdev;
};
static const u32 rst_map[] = {
BIT(16), /* APB_RST */
BIT(17), /* AXI_RST */
BIT(18), /* ETH_RST */
BIT(19), /* USB_RST */
BIT(20), /* SDIO_RST */
BIT(21), /* HDMI_RST */
BIT(22), /* GFX_RST */
BIT(25), /* DMAC_RST */
BIT(31), /* EBI_RST */
};
#define HSDK_MAX_RESETS ARRAY_SIZE(rst_map)
#define CGU_SYS_RST_CTRL 0x0
#define CGU_IP_SW_RESET 0x0
#define CGU_IP_SW_RESET_DELAY_SHIFT 16
#define CGU_IP_SW_RESET_DELAY_MASK GENMASK(31, CGU_IP_SW_RESET_DELAY_SHIFT)
#define CGU_IP_SW_RESET_DELAY 0
#define CGU_IP_SW_RESET_RESET BIT(0)
#define SW_RESET_TIMEOUT 10000
static void hsdk_reset_config(struct hsdk_rst *rst, unsigned long id)
{
writel(rst_map[id], rst->regs_ctl + CGU_SYS_RST_CTRL);
}
static int hsdk_reset_do(struct hsdk_rst *rst)
{
u32 reg;
reg = readl(rst->regs_rst + CGU_IP_SW_RESET);
reg &= ~CGU_IP_SW_RESET_DELAY_MASK;
reg |= CGU_IP_SW_RESET_DELAY << CGU_IP_SW_RESET_DELAY_SHIFT;
reg |= CGU_IP_SW_RESET_RESET;
writel(reg, rst->regs_rst + CGU_IP_SW_RESET);
/* wait till reset bit is back to 0 */
return readl_poll_timeout_atomic(rst->regs_rst + CGU_IP_SW_RESET, reg,
!(reg & CGU_IP_SW_RESET_RESET), 5, SW_RESET_TIMEOUT);
}
static int hsdk_reset_reset(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct hsdk_rst *rst = to_hsdk_rst(rcdev);
unsigned long flags;
int ret;
spin_lock_irqsave(&rst->lock, flags);
hsdk_reset_config(rst, id);
ret = hsdk_reset_do(rst);
spin_unlock_irqrestore(&rst->lock, flags);
return ret;
}
static const struct reset_control_ops hsdk_reset_ops = {
.reset = hsdk_reset_reset,
};
static int hsdk_reset_probe(struct platform_device *pdev)
{
struct hsdk_rst *rst;
struct resource *mem;
rst = devm_kzalloc(&pdev->dev, sizeof(*rst), GFP_KERNEL);
if (!rst)
return -ENOMEM;
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
rst->regs_ctl = devm_ioremap_resource(&pdev->dev, mem);
if (IS_ERR(rst->regs_ctl))
return PTR_ERR(rst->regs_ctl);
mem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
rst->regs_rst = devm_ioremap_resource(&pdev->dev, mem);
if (IS_ERR(rst->regs_rst))
return PTR_ERR(rst->regs_rst);
spin_lock_init(&rst->lock);
rst->rcdev.owner = THIS_MODULE;
rst->rcdev.ops = &hsdk_reset_ops;
rst->rcdev.of_node = pdev->dev.of_node;
rst->rcdev.nr_resets = HSDK_MAX_RESETS;
rst->rcdev.of_reset_n_cells = 1;
return reset_controller_register(&rst->rcdev);
}
static const struct of_device_id hsdk_reset_dt_match[] = {
{ .compatible = "snps,hsdk-reset" },
{ },
};
static struct platform_driver hsdk_reset_driver = {
.probe = hsdk_reset_probe,
.driver = {
.name = "hsdk-reset",
.of_match_table = hsdk_reset_dt_match,
},
};
builtin_platform_driver(hsdk_reset_driver);
MODULE_AUTHOR("Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>");
MODULE_DESCRIPTION("Synopsys HSDK SDP reset driver");
MODULE_LICENSE("GPL v2");