WSL2-Linux-Kernel/arch/mips/lantiq/xway/reset.c

166 строки
4.0 KiB
C

/*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*
* Copyright (C) 2010 John Crispin <blogic@openwrt.org>
*/
#include <linux/init.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/pm.h>
#include <linux/export.h>
#include <linux/delay.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>
#include <asm/reboot.h>
#include <lantiq_soc.h>
#include "../prom.h"
#define ltq_rcu_w32(x, y) ltq_w32((x), ltq_rcu_membase + (y))
#define ltq_rcu_r32(x) ltq_r32(ltq_rcu_membase + (x))
/* reset request register */
#define RCU_RST_REQ 0x0010
/* reset status register */
#define RCU_RST_STAT 0x0014
/* vr9 gphy registers */
#define RCU_GFS_ADD0_XRX200 0x0020
#define RCU_GFS_ADD1_XRX200 0x0068
/* reboot bit */
#define RCU_RD_GPHY0_XRX200 BIT(31)
#define RCU_RD_SRST BIT(30)
#define RCU_RD_GPHY1_XRX200 BIT(29)
/* reset cause */
#define RCU_STAT_SHIFT 26
/* boot selection */
#define RCU_BOOT_SEL(x) ((x >> 18) & 0x7)
#define RCU_BOOT_SEL_XRX200(x) (((x >> 17) & 0xf) | ((x >> 8) & 0x10))
/* remapped base addr of the reset control unit */
static void __iomem *ltq_rcu_membase;
static struct device_node *ltq_rcu_np;
/* This function is used by the watchdog driver */
int ltq_reset_cause(void)
{
u32 val = ltq_rcu_r32(RCU_RST_STAT);
return val >> RCU_STAT_SHIFT;
}
EXPORT_SYMBOL_GPL(ltq_reset_cause);
/* allow platform code to find out what source we booted from */
unsigned char ltq_boot_select(void)
{
u32 val = ltq_rcu_r32(RCU_RST_STAT);
if (of_device_is_compatible(ltq_rcu_np, "lantiq,rcu-xrx200"))
return RCU_BOOT_SEL_XRX200(val);
return RCU_BOOT_SEL(val);
}
/* reset / boot a gphy */
static struct ltq_xrx200_gphy_reset {
u32 rd;
u32 addr;
} xrx200_gphy[] = {
{RCU_RD_GPHY0_XRX200, RCU_GFS_ADD0_XRX200},
{RCU_RD_GPHY1_XRX200, RCU_GFS_ADD1_XRX200},
};
/* reset and boot a gphy. these phys only exist on xrx200 SoC */
int xrx200_gphy_boot(struct device *dev, unsigned int id, dma_addr_t dev_addr)
{
struct clk *clk;
if (!of_device_is_compatible(ltq_rcu_np, "lantiq,rcu-xrx200")) {
dev_err(dev, "this SoC has no GPHY\n");
return -EINVAL;
}
clk = clk_get_sys("1f203000.rcu", "gphy");
if (IS_ERR(clk))
return PTR_ERR(clk);
clk_enable(clk);
if (id > 1) {
dev_err(dev, "%u is an invalid gphy id\n", id);
return -EINVAL;
}
dev_info(dev, "booting GPHY%u firmware at %X\n", id, dev_addr);
ltq_rcu_w32(ltq_rcu_r32(RCU_RST_REQ) | xrx200_gphy[id].rd,
RCU_RST_REQ);
ltq_rcu_w32(dev_addr, xrx200_gphy[id].addr);
ltq_rcu_w32(ltq_rcu_r32(RCU_RST_REQ) & ~xrx200_gphy[id].rd,
RCU_RST_REQ);
return 0;
}
/* reset a io domain for u micro seconds */
void ltq_reset_once(unsigned int module, ulong u)
{
ltq_rcu_w32(ltq_rcu_r32(RCU_RST_REQ) | module, RCU_RST_REQ);
udelay(u);
ltq_rcu_w32(ltq_rcu_r32(RCU_RST_REQ) & ~module, RCU_RST_REQ);
}
static void ltq_machine_restart(char *command)
{
local_irq_disable();
ltq_rcu_w32(ltq_rcu_r32(RCU_RST_REQ) | RCU_RD_SRST, RCU_RST_REQ);
unreachable();
}
static void ltq_machine_halt(void)
{
local_irq_disable();
unreachable();
}
static void ltq_machine_power_off(void)
{
local_irq_disable();
unreachable();
}
static int __init mips_reboot_setup(void)
{
struct resource res;
ltq_rcu_np = of_find_compatible_node(NULL, NULL, "lantiq,rcu-xway");
if (!ltq_rcu_np)
ltq_rcu_np = of_find_compatible_node(NULL, NULL,
"lantiq,rcu-xrx200");
/* check if all the reset register range is available */
if (!ltq_rcu_np)
panic("Failed to load reset resources from devicetree");
if (of_address_to_resource(ltq_rcu_np, 0, &res))
panic("Failed to get rcu memory range");
if (request_mem_region(res.start, resource_size(&res), res.name) < 0)
pr_err("Failed to request rcu memory");
ltq_rcu_membase = ioremap_nocache(res.start, resource_size(&res));
if (!ltq_rcu_membase)
panic("Failed to remap core memory");
_machine_restart = ltq_machine_restart;
_machine_halt = ltq_machine_halt;
pm_power_off = ltq_machine_power_off;
return 0;
}
arch_initcall(mips_reboot_setup);