Re: [PATCH 1/2] ARM: STi: Add code to release secondary cores from holding pen.

From: Maxime Coquelin
Date: Tue Jun 09 2015 - 05:18:27 EST


Hi Peter,

On 06/08/2015 06:16 PM, Peter Griffin wrote:
Most upstream devs boot STi platform via JTAG which abuses the
boot process by setting the PC of secondary cores directly. As
a consquence, booting STi platforms via u-boot results in only
the primary core being brought up as the code to manage the
holding pen is not upstream.

This patch adds the necessary code to bring the secondary cores
out of the holding pen. It uses the cpu-release-addr DT property
to get the address of the holding pen from the bootloader.

With this patch booting upstream kernels via u-boot works
correctly:

[ 0.045456] CPU: Testing write buffer coherency: ok
[ 0.045597] CPU0: thread -1, cpu 0, socket 0, mpidr 80000000
[ 0.045734] Setting up static identity map for 0x40209000 - 0x40209098
[ 0.065047] CPU1: thread -1, cpu 1, socket 0, mpidr 80000001
[ 0.065081] Brought up 2 CPUs
[ 0.065089] SMP: Total of 2 processors activated (5983.43 BogoMIPS).
[ 0.065092] CPU: All CPU(s) started in SVC mode.

Signed-off-by: Peter Griffin <peter.griffin@xxxxxxxxxx>
---
arch/arm/mach-sti/headsmp.S | 1 +
arch/arm/mach-sti/platsmp.c | 56 ++++++++++++++++++++++++++++++++++++++++++---
arch/arm/mach-sti/smp.h | 2 ++
3 files changed, 56 insertions(+), 3 deletions(-)


diff --git a/arch/arm/mach-sti/platsmp.c b/arch/arm/mach-sti/platsmp.c
index d4b624f..6597ed8 100644
--- a/arch/arm/mach-sti/platsmp.c
+++ b/arch/arm/mach-sti/platsmp.c

struct smp_operations __initdata sti_smp_ops = {
@@ -114,3 +163,4 @@ struct smp_operations __initdata sti_smp_ops = {
.smp_secondary_init = sti_secondary_init,
.smp_boot_secondary = sti_boot_secondary,
};
+
Please remove trailing line.

Once fixed, you can add:
Acked-by: Maxime Coquelin <maxime.coquelin@xxxxxx>

Thanks!
Maxime
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