From 76cb841cb886eef6b3bee341a2266c76578724ad Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 6 May 2024 03:02:30 +0200 Subject: Adding upstream version 4.19.249. Signed-off-by: Daniel Baumann --- arch/arm/mach-imx/hotplug.c | 70 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 70 insertions(+) create mode 100644 arch/arm/mach-imx/hotplug.c (limited to 'arch/arm/mach-imx/hotplug.c') diff --git a/arch/arm/mach-imx/hotplug.c b/arch/arm/mach-imx/hotplug.c new file mode 100644 index 000000000..b35e99cc5 --- /dev/null +++ b/arch/arm/mach-imx/hotplug.c @@ -0,0 +1,70 @@ +/* + * Copyright 2011 Freescale Semiconductor, Inc. + * Copyright 2011 Linaro Ltd. + * + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +#include +#include +#include +#include + +#include "common.h" + +static inline void cpu_enter_lowpower(void) +{ + unsigned int v; + + asm volatile( + "mcr p15, 0, %1, c7, c5, 0\n" + " mcr p15, 0, %1, c7, c10, 4\n" + /* + * Turn off coherency + */ + " mrc p15, 0, %0, c1, c0, 1\n" + " bic %0, %0, %3\n" + " mcr p15, 0, %0, c1, c0, 1\n" + " mrc p15, 0, %0, c1, c0, 0\n" + " bic %0, %0, %2\n" + " mcr p15, 0, %0, c1, c0, 0\n" + : "=&r" (v) + : "r" (0), "Ir" (CR_C), "Ir" (0x40) + : "cc"); +} + +/* + * platform-specific code to shutdown a CPU + * + * Called with IRQs disabled + */ +void imx_cpu_die(unsigned int cpu) +{ + cpu_enter_lowpower(); + /* + * We use the cpu jumping argument register to sync with + * imx_cpu_kill() which is running on cpu0 and waiting for + * the register being cleared to kill the cpu. + */ + imx_set_cpu_arg(cpu, ~0); + + while (1) + cpu_do_idle(); +} + +int imx_cpu_kill(unsigned int cpu) +{ + unsigned long timeout = jiffies + msecs_to_jiffies(50); + + while (imx_get_cpu_arg(cpu) == 0) + if (time_after(jiffies, timeout)) + return 0; + imx_enable_cpu(cpu, false); + imx_set_cpu_arg(cpu, 0); + return 1; +} -- cgit v1.2.3