mirror of
https://github.com/torvalds/linux.git
synced 2024-11-08 05:01:48 +00:00
8f65873e47
Blackfin dual core BF561 processor can support SMP like features. https://docs.blackfin.uclinux.org/doku.php?id=linux-kernel:smp-like In this patch, we provide SMP extend to Blackfin kernel and memory management code Singed-off-by: Graf Yang <graf.yang@analog.com> Signed-off-by: Mike Frysinger <vapier.adi@gmail.com> Signed-off-by: Bryan Wu <cooloney@kernel.org>
117 lines
2.5 KiB
C
117 lines
2.5 KiB
C
/*
|
|
* arch/blackfin/kernel/reboot.c - handle shutdown/reboot
|
|
*
|
|
* Copyright 2004-2007 Analog Devices Inc.
|
|
*
|
|
* Licensed under the GPL-2 or later.
|
|
*/
|
|
|
|
#include <linux/interrupt.h>
|
|
#include <asm/bfin-global.h>
|
|
#include <asm/reboot.h>
|
|
#include <asm/system.h>
|
|
#include <asm/bfrom.h>
|
|
|
|
/* A system soft reset makes external memory unusable so force
|
|
* this function into L1. We use the compiler ssync here rather
|
|
* than SSYNC() because it's safe (no interrupts and such) and
|
|
* we save some L1. We do not need to force sanity in the SYSCR
|
|
* register as the BMODE selection bit is cleared by the soft
|
|
* reset while the Core B bit (on dual core parts) is cleared by
|
|
* the core reset.
|
|
*/
|
|
__attribute__((l1_text))
|
|
static void _bfin_reset(void)
|
|
{
|
|
/* Wait for completion of "system" events such as cache line
|
|
* line fills so that we avoid infinite stalls later on as
|
|
* much as possible. This code is in L1, so it won't trigger
|
|
* any such event after this point in time.
|
|
*/
|
|
__builtin_bfin_ssync();
|
|
|
|
while (1) {
|
|
/* Initiate System software reset. */
|
|
bfin_write_SWRST(0x7);
|
|
|
|
/* Due to the way reset is handled in the hardware, we need
|
|
* to delay for 10 SCLKS. The only reliable way to do this is
|
|
* to calculate the CCLK/SCLK ratio and multiply 10. For now,
|
|
* we'll assume worse case which is a 1:15 ratio.
|
|
*/
|
|
asm(
|
|
"LSETUP (1f, 1f) LC0 = %0\n"
|
|
"1: nop;"
|
|
:
|
|
: "a" (15 * 10)
|
|
: "LC0", "LB0", "LT0"
|
|
);
|
|
|
|
/* Clear System software reset */
|
|
bfin_write_SWRST(0);
|
|
|
|
/* Wait for the SWRST write to complete. Cannot rely on SSYNC
|
|
* though as the System state is all reset now.
|
|
*/
|
|
asm(
|
|
"LSETUP (1f, 1f) LC1 = %0\n"
|
|
"1: nop;"
|
|
:
|
|
: "a" (15 * 1)
|
|
: "LC1", "LB1", "LT1"
|
|
);
|
|
|
|
/* Issue core reset */
|
|
asm("raise 1");
|
|
}
|
|
}
|
|
|
|
static void bfin_reset(void)
|
|
{
|
|
if (ANOMALY_05000353 || ANOMALY_05000386)
|
|
_bfin_reset();
|
|
else
|
|
/* the bootrom checks to see how it was reset and will
|
|
* automatically perform a software reset for us when
|
|
* it starts executing boot
|
|
*/
|
|
asm("raise 1;");
|
|
}
|
|
|
|
__attribute__((weak))
|
|
void native_machine_restart(char *cmd)
|
|
{
|
|
}
|
|
|
|
void machine_restart(char *cmd)
|
|
{
|
|
native_machine_restart(cmd);
|
|
local_irq_disable();
|
|
if (smp_processor_id())
|
|
smp_call_function((void *)bfin_reset, 0, 1);
|
|
else
|
|
bfin_reset();
|
|
}
|
|
|
|
__attribute__((weak))
|
|
void native_machine_halt(void)
|
|
{
|
|
idle_with_irq_disabled();
|
|
}
|
|
|
|
void machine_halt(void)
|
|
{
|
|
native_machine_halt();
|
|
}
|
|
|
|
__attribute__((weak))
|
|
void native_machine_power_off(void)
|
|
{
|
|
idle_with_irq_disabled();
|
|
}
|
|
|
|
void machine_power_off(void)
|
|
{
|
|
native_machine_power_off();
|
|
}
|