linux/arch/arm/mach-realview/hotplug.c
Stephen Boyd b96fc2f3c1 ARM: Remove __ref on hotplug cpu die path
Now that __cpuinit has been removed, the __ref markings on these
functions are useless. Remove them. This also reduces the size of
the multi_v7_defconfig image:

$ size before after
   text    data     bss     dec     hex filename
   12683578        1470996  348904 14503478         dd4e36 before
   12683274        1470996  348904 14503174         dd4d06 after

presumably because now we don't have to jump to code in the
.ref.text section and/or the noinline marking is removed.

Cc: Shiraz Hashim <shiraz.linux.kernel@gmail.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: <linux-omap@vger.kernel.org>
Cc: <linux-arm-msm@vger.kernel.org>
Cc: <spear-devel@list.st.com>
Cc: <linux-tegra@vger.kernel.org>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Barry Song <baohua@kernel.org>
Acked-by: Andy Gross <agross@codeaurora.org>
Acked-by: Viresh Kumar <vireshk@kernel.org>
Acked-by: Thierry Reding <thierry.reding@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Olof Johansson <olof@lixom.net>
2015-10-22 09:55:03 -07:00

112 lines
2.3 KiB
C

/*
* linux/arch/arm/mach-realview/hotplug.c
*
* Copyright (C) 2002 ARM Ltd.
* All Rights Reserved
*
* 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.
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/smp.h>
#include <asm/cp15.h>
#include <asm/smp_plat.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, #0x20\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)
: "cc");
}
static inline void cpu_leave_lowpower(void)
{
unsigned int v;
asm volatile( "mrc p15, 0, %0, c1, c0, 0\n"
" orr %0, %0, %1\n"
" mcr p15, 0, %0, c1, c0, 0\n"
" mrc p15, 0, %0, c1, c0, 1\n"
" orr %0, %0, #0x20\n"
" mcr p15, 0, %0, c1, c0, 1\n"
: "=&r" (v)
: "Ir" (CR_C)
: "cc");
}
static inline void platform_do_lowpower(unsigned int cpu, int *spurious)
{
/*
* there is no power-control hardware on this platform, so all
* we can do is put the core into WFI; this is safe as the calling
* code will have already disabled interrupts
*/
for (;;) {
/*
* here's the WFI
*/
asm(".word 0xe320f003\n"
:
:
: "memory", "cc");
if (pen_release == cpu_logical_map(cpu)) {
/*
* OK, proper wakeup, we're done
*/
break;
}
/*
* Getting here, means that we have come out of WFI without
* having been woken up - this shouldn't happen
*
* Just note it happening - when we're woken, we can report
* its occurrence.
*/
(*spurious)++;
}
}
/*
* platform-specific code to shutdown a CPU
*
* Called with IRQs disabled
*/
void realview_cpu_die(unsigned int cpu)
{
int spurious = 0;
/*
* we're ready for shutdown now, so do it
*/
cpu_enter_lowpower();
platform_do_lowpower(cpu, &spurious);
/*
* bring this CPU back into the world of cache
* coherency, and then restore interrupts
*/
cpu_leave_lowpower();
if (spurious)
pr_warn("CPU%u: %u spurious wakeup calls\n", cpu, spurious);
}