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https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
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e34645f458
Add SMP support for i.MX7D, including CPU hotplug support, for systems where TFA is not present. The motivation for bringing up the second i.MX7D core inside the kernel is that legacy vendor bootloaders usually do not implement PSCI support. This is a significant blocker for systems in the field that are running old bootloader versions to upgrade to a modern mainline kernel version, as only one CPU of the i.MX7D would be brought up. Bring up the second i.MX7D core inside the kernel to make the migration path to mainline kernel easier for the existing iMX7D users. Signed-off-by: Anson Huang <b20788@freescale.com> Signed-off-by: Arulpandiyan Vadivel <arulpandiyan_vadivel@mentor.com> # Fix merge conflicts Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com> Signed-off-by: Marek Vasut <marex@denx.de> # heavy cleanup Signed-off-by: Fabio Estevam <festevam@denx.de> Signed-off-by: Shawn Guo <shawnguo@kernel.org>
47 lines
1,007 B
C
47 lines
1,007 B
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* Copyright 2011 Freescale Semiconductor, Inc.
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* Copyright 2011 Linaro Ltd.
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*/
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#include <linux/errno.h>
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#include <linux/jiffies.h>
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#include <asm/cacheflush.h>
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#include <asm/cp15.h>
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#include <asm/proc-fns.h>
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#include "common.h"
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#include "hardware.h"
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/*
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* platform-specific code to shutdown a CPU
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*
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* Called with IRQs disabled
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*/
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void imx_cpu_die(unsigned int cpu)
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{
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v7_exit_coherency_flush(louis);
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/*
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* We use the cpu jumping argument register to sync with
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* imx_cpu_kill() which is running on cpu0 and waiting for
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* the register being cleared to kill the cpu.
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*/
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imx_set_cpu_arg(cpu, ~0);
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while (1)
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cpu_do_idle();
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}
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int imx_cpu_kill(unsigned int cpu)
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{
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unsigned long timeout = jiffies + msecs_to_jiffies(50);
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while (imx_get_cpu_arg(cpu) == 0)
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if (time_after(jiffies, timeout))
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return 0;
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imx_enable_cpu(cpu, false);
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imx_set_cpu_arg(cpu, 0);
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if (cpu_is_imx7d())
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imx_gpcv2_set_core1_pdn_pup_by_software(true);
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return 1;
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}
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