linux-stable/arch/mips/generic/board-ingenic.c
Paul Cercueil 71f8817c28 MIPS: ingenic: Unconditionally enable clock of CPU #0
Make sure that the PLL that feeds the CPU won't be stopped while the
kernel is running.

This fixes a problem on JZ4760 (and probably others) where under very
specific conditions, the main PLL would be turned OFF when the kernel
was shutting down, causing the shutdown process to fail.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2021-08-29 13:31:02 +02:00

169 lines
4.5 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Support for Ingenic SoCs
*
* Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
* Copyright (C) 2011, Maarten ter Huurne <maarten@treewalker.org>
* Copyright (C) 2020 Paul Cercueil <paul@crapouillou.net>
*/
#include <linux/clk.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_fdt.h>
#include <linux/pm.h>
#include <linux/sizes.h>
#include <linux/suspend.h>
#include <linux/types.h>
#include <asm/bootinfo.h>
#include <asm/machine.h>
#include <asm/reboot.h>
static __init char *ingenic_get_system_type(unsigned long machtype)
{
switch (machtype) {
case MACH_INGENIC_X2100:
return "X2100";
case MACH_INGENIC_X2000H:
return "X2000H";
case MACH_INGENIC_X2000E:
return "X2000E";
case MACH_INGENIC_X2000:
return "X2000";
case MACH_INGENIC_X1830:
return "X1830";
case MACH_INGENIC_X1000E:
return "X1000E";
case MACH_INGENIC_X1000:
return "X1000";
case MACH_INGENIC_JZ4780:
return "JZ4780";
case MACH_INGENIC_JZ4775:
return "JZ4775";
case MACH_INGENIC_JZ4770:
return "JZ4770";
case MACH_INGENIC_JZ4760B:
return "JZ4760B";
case MACH_INGENIC_JZ4760:
return "JZ4760";
case MACH_INGENIC_JZ4755:
return "JZ4755";
case MACH_INGENIC_JZ4750:
return "JZ4750";
case MACH_INGENIC_JZ4725B:
return "JZ4725B";
case MACH_INGENIC_JZ4730:
return "JZ4730";
default:
return "JZ4740";
}
}
static __init const void *ingenic_fixup_fdt(const void *fdt, const void *match_data)
{
/*
* Old devicetree files for the qi,lb60 board did not have a /memory
* node. Hardcode the memory info here.
*/
if (!fdt_node_check_compatible(fdt, 0, "qi,lb60") &&
fdt_path_offset(fdt, "/memory") < 0)
early_init_dt_add_memory_arch(0, SZ_32M);
mips_machtype = (unsigned long)match_data;
system_type = ingenic_get_system_type(mips_machtype);
return fdt;
}
static const struct of_device_id ingenic_of_match[] __initconst = {
{ .compatible = "ingenic,jz4730", .data = (void *)MACH_INGENIC_JZ4730 },
{ .compatible = "ingenic,jz4740", .data = (void *)MACH_INGENIC_JZ4740 },
{ .compatible = "ingenic,jz4725b", .data = (void *)MACH_INGENIC_JZ4725B },
{ .compatible = "ingenic,jz4750", .data = (void *)MACH_INGENIC_JZ4750 },
{ .compatible = "ingenic,jz4755", .data = (void *)MACH_INGENIC_JZ4755 },
{ .compatible = "ingenic,jz4760", .data = (void *)MACH_INGENIC_JZ4760 },
{ .compatible = "ingenic,jz4760b", .data = (void *)MACH_INGENIC_JZ4760B },
{ .compatible = "ingenic,jz4770", .data = (void *)MACH_INGENIC_JZ4770 },
{ .compatible = "ingenic,jz4775", .data = (void *)MACH_INGENIC_JZ4775 },
{ .compatible = "ingenic,jz4780", .data = (void *)MACH_INGENIC_JZ4780 },
{ .compatible = "ingenic,x1000", .data = (void *)MACH_INGENIC_X1000 },
{ .compatible = "ingenic,x1000e", .data = (void *)MACH_INGENIC_X1000E },
{ .compatible = "ingenic,x1830", .data = (void *)MACH_INGENIC_X1830 },
{ .compatible = "ingenic,x2000", .data = (void *)MACH_INGENIC_X2000 },
{ .compatible = "ingenic,x2000e", .data = (void *)MACH_INGENIC_X2000E },
{ .compatible = "ingenic,x2000h", .data = (void *)MACH_INGENIC_X2000H },
{ .compatible = "ingenic,x2100", .data = (void *)MACH_INGENIC_X2100 },
{}
};
MIPS_MACHINE(ingenic) = {
.matches = ingenic_of_match,
.fixup_fdt = ingenic_fixup_fdt,
};
static void ingenic_wait_instr(void)
{
__asm__(".set push;\n"
".set mips3;\n"
"wait;\n"
".set pop;\n"
);
}
static void ingenic_halt(void)
{
for (;;)
ingenic_wait_instr();
}
static int __maybe_unused ingenic_pm_enter(suspend_state_t state)
{
ingenic_wait_instr();
return 0;
}
static const struct platform_suspend_ops ingenic_pm_ops __maybe_unused = {
.valid = suspend_valid_only_mem,
.enter = ingenic_pm_enter,
};
static int __init ingenic_pm_init(void)
{
struct device_node *cpu_node;
struct clk *cpu0_clk;
int ret;
if (boot_cpu_type() == CPU_XBURST) {
if (IS_ENABLED(CONFIG_PM_SLEEP))
suspend_set_ops(&ingenic_pm_ops);
_machine_halt = ingenic_halt;
/*
* Unconditionally enable the clock for the first CPU.
* This makes sure that the PLL that feeds the CPU won't be
* stopped while the kernel is running.
*/
cpu_node = of_get_cpu_node(0, NULL);
if (!cpu_node) {
pr_err("Unable to get CPU node\n");
} else {
cpu0_clk = of_clk_get(cpu_node, 0);
if (IS_ERR(cpu0_clk)) {
pr_err("Unable to get CPU0 clock\n");
return PTR_ERR(cpu0_clk);
}
ret = clk_prepare_enable(cpu0_clk);
if (ret) {
pr_err("Unable to enable CPU0 clock\n");
return ret;
}
}
}
return 0;
}
late_initcall(ingenic_pm_init);