Commit 6becef7e authored by chenhui zhao's avatar chenhui zhao Committed by Scott Wood

powerpc/mpc85xx: Add CPU hotplug support for E6500

Support Freescale E6500 core-based platforms, like t4240.
Support disabling/enabling individual CPU thread dynamically.
Signed-off-by: default avatarChenhui Zhao <chenhui.zhao@freescale.com>
parent 2f4f1f81
#ifndef _ASM_POWERPC_CPUTHREADS_H
#define _ASM_POWERPC_CPUTHREADS_H
#ifndef __ASSEMBLY__
#include <linux/cpumask.h>
/*
......@@ -103,7 +104,12 @@ static inline u32 get_tensr(void)
return 1;
}
void book3e_start_thread(int thread, unsigned long addr);
void book3e_stop_thread(int thread);
#endif /* __ASSEMBLY__ */
#define INVALID_THREAD_HWID 0x0fff
#endif /* _ASM_POWERPC_CPUTHREADS_H */
......@@ -200,6 +200,7 @@ extern void generic_secondary_thread_init(void);
extern unsigned long __secondary_hold_spinloop;
extern unsigned long __secondary_hold_acknowledge;
extern char __secondary_hold;
extern unsigned int booting_thread_hwid;
extern void __early_start(void);
#endif /* __ASSEMBLY__ */
......
......@@ -40,6 +40,7 @@
#include <asm/kvm_book3s_asm.h>
#include <asm/ptrace.h>
#include <asm/hw_irq.h>
#include <asm/cputhreads.h>
/* The physical memory is laid out such that the secondary processor
* spin code sits at 0x0000...0x00ff. On server, the vectors follow
......@@ -181,6 +182,45 @@ exception_marker:
#endif
#ifdef CONFIG_PPC_BOOK3E
/*
* The booting_thread_hwid holds the thread id we want to boot in cpu
* hotplug case. It is set by cpu hotplug code, and is invalid by default.
* The thread id is the same as the initial value of SPRN_PIR[THREAD_ID]
* bit field.
*/
.globl booting_thread_hwid
booting_thread_hwid:
.long INVALID_THREAD_HWID
.align 3
/*
* start a thread in the same core
* input parameters:
* r3 = the thread physical id
* r4 = the entry point where thread starts
*/
_GLOBAL(book3e_start_thread)
LOAD_REG_IMMEDIATE(r5, MSR_KERNEL)
cmpi 0, r3, 0
beq 10f
cmpi 0, r3, 1
beq 11f
/* If the thread id is invalid, just exit. */
b 13f
10:
mttmr TMRN_IMSR0, r5
mttmr TMRN_INIA0, r4
b 12f
11:
mttmr TMRN_IMSR1, r5
mttmr TMRN_INIA1, r4
12:
isync
li r6, 1
sld r6, r6, r3
mtspr SPRN_TENS, r6
13:
blr
/*
* stop a thread in the same core
* input parameter:
......@@ -280,6 +320,44 @@ _GLOBAL(generic_secondary_smp_init)
mr r3,r24
mr r4,r25
bl book3e_secondary_core_init
/*
* After common core init has finished, check if the current thread is the
* one we wanted to boot. If not, start the specified thread and stop the
* current thread.
*/
LOAD_REG_ADDR(r4, booting_thread_hwid)
lwz r3, 0(r4)
li r5, INVALID_THREAD_HWID
cmpw r3, r5
beq 20f
/*
* The value of booting_thread_hwid has been stored in r3,
* so make it invalid.
*/
stw r5, 0(r4)
/*
* Get the current thread id and check if it is the one we wanted.
* If not, start the one specified in booting_thread_hwid and stop
* the current thread.
*/
mfspr r8, SPRN_TIR
cmpw r3, r8
beq 20f
/* start the specified thread */
LOAD_REG_ADDR(r5, fsl_secondary_thread_init)
ld r4, 0(r5)
bl book3e_start_thread
/* stop the current thread */
mr r3, r8
bl book3e_stop_thread
10:
b 10b
20:
#endif
generic_secondary_common_init:
......
......@@ -180,24 +180,11 @@ static inline u32 read_spin_table_addr_l(void *spin_table)
static void wake_hw_thread(void *info)
{
void fsl_secondary_thread_init(void);
unsigned long imsr, inia;
int nr = *(const int *)info;
unsigned long inia;
int cpu = *(const int *)info;
imsr = MSR_KERNEL;
inia = *(unsigned long *)fsl_secondary_thread_init;
if (cpu_thread_in_core(nr) == 0) {
/* For when we boot on a secondary thread with kdump */
mttmr(TMRN_IMSR0, imsr);
mttmr(TMRN_INIA0, inia);
mtspr(SPRN_TENS, TEN_THREAD(0));
} else {
mttmr(TMRN_IMSR1, imsr);
mttmr(TMRN_INIA1, inia);
mtspr(SPRN_TENS, TEN_THREAD(1));
}
smp_generic_kick_cpu(nr);
book3e_start_thread(cpu_thread_in_core(cpu), inia);
}
#endif
......@@ -292,33 +279,54 @@ static int smp_85xx_kick_cpu(int nr)
pr_debug("kick CPU #%d\n", nr);
#ifdef CONFIG_PPC64
/* Threads don't use the spin table */
if (cpu_thread_in_core(nr) != 0) {
int primary = cpu_first_thread_sibling(nr);
if (threads_per_core == 2) {
if (WARN_ON_ONCE(!cpu_has_feature(CPU_FTR_SMT)))
return -ENOENT;
if (cpu_thread_in_core(nr) != 1) {
pr_err("%s: cpu %d: invalid hw thread %d\n",
__func__, nr, cpu_thread_in_core(nr));
return -ENOENT;
}
booting_thread_hwid = cpu_thread_in_core(nr);
primary = cpu_first_thread_sibling(nr);
if (!cpu_online(primary)) {
pr_err("%s: cpu %d: primary %d not online\n",
__func__, nr, primary);
return -ENOENT;
if (qoriq_pm_ops)
qoriq_pm_ops->cpu_up_prepare(nr);
/*
* If either thread in the core is online, use it to start
* the other.
*/
if (cpu_online(primary)) {
smp_call_function_single(primary,
wake_hw_thread, &nr, 1);
goto done;
} else if (cpu_online(primary + 1)) {
smp_call_function_single(primary + 1,
wake_hw_thread, &nr, 1);
goto done;
}
smp_call_function_single(primary, wake_hw_thread, &nr, 0);
return 0;
/*
* If getting here, it means both threads in the core are
* offline. So start the primary thread, then it will start
* the thread specified in booting_thread_hwid, the one
* corresponding to nr.
*/
} else if (threads_per_core == 1) {
/*
* If one core has only one thread, set booting_thread_hwid to
* an invalid value.
*/
booting_thread_hwid = INVALID_THREAD_HWID;
} else if (threads_per_core > 2) {
pr_err("Do not support more than 2 threads per CPU.");
return -EINVAL;
}
ret = smp_85xx_start_cpu(primary);
if (ret)
return ret;
done:
paca[nr].cpu_start = 1;
generic_set_cpu_up(nr);
......
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