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>
This commit is contained in:
Paul Cercueil 2021-08-23 18:34:05 +01:00 committed by Thomas Bogendoerfer
parent eba54cbb92
commit 71f8817c28
1 changed files with 28 additions and 0 deletions

View File

@ -7,6 +7,8 @@
* 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>
@ -129,10 +131,36 @@ static const struct platform_suspend_ops ingenic_pm_ops __maybe_unused = {
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;