armbian/linux
0
0
Fork 0
mirror of https://github.com/armbian/linux.git synced 2026-01-06 10:13:00 -08:00
Code Issues Packages Projects Releases Wiki Activity

ARM: TC2: reset CPUs spuriously woken up on cluster power up

Browse Source 
On TC2, all CPUs in a cluster are woken up when an IRQ event triggers for a
CPU in a cluster in shutdown state.

This patch puts spuriously woken CPUs back in reset by checking the
pending IRQ status in the SPC wake-up interrupt status register; if the
CPU has no pending IRQ routed to it, the core reexecutes wfi and it is put
in reset by FW straight away.

Tested-by: Viresh Kumar <viresh.kumar2@arm.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
This commit is contained in:
Lorenzo Pieralisi
2013-03-14 14:07:20 +00:00
committed by Jon Medhurst
parent 62373580b2
commit aa55d8151d
2 changed files with 17 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
arch/arm/mach-vexpress/tc2_pm.c
View File

@@ -172,13 +172,15 @@ static void tc2_pm_power_down(void)
static void tc2_pm_suspend(u64 residency)
{
extern void tc2_resume(void);
unsigned int mpidr, cpu, cluster;
mpidr = read_cpuid_mpidr();
cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
vexpress_spc_write_bxaddr_reg(cluster, cpu,
virt_to_phys(mcpm_entry_point));
virt_to_phys(tc2_resume));
tc2_pm_down(residency);
}

14
arch/arm/mach-vexpress/tc2_pm_setup.S
View File

@@ -16,6 +16,7 @@
#define SPC_PHYS_BASE 0x7FFF0000
#define SPC_WAKE_INT_STAT 0xb2c
#define SNOOP_CTL_A15 0x404
#define SNOOP_CTL_A7 0x504
@@ -42,6 +43,19 @@
#define CCI_A7_OFFSET CCI_SLAVE_OFFSET(CCI_SLAVE_A7)
ENTRY(tc2_resume)
mrc p15, 0, r0, c0, c0, 5
ubfx r1, r0, #0, #4 @ r1 = cpu
ubfx r2, r0, #8, #4 @ r2 = cluster
add r1, r1, r2, lsl #2 @ r1 = index of CPU in WAKE_INT_STAT
ldr r3, =SPC_PHYS_BASE + SPC_WAKE_INT_STAT
ldr r3, [r3]
lsr r3, r1
tst r3, #1
wfieq @ if no pending IRQ reenters wfi
b mcpm_entry_point
ENDPROC(tc2_resume)
/*
* Enable cluster-level coherency, in preparation for turning on the MMU.
* The ACTLR SMP bit does not need to be set here, because cpu_resume()