Re: [PATCH] ARM: zynq: use physical cpuid in zynq_slcr_cpu_stop/start

From: Michal Simek
Date: Wed Jan 08 2020 - 09:20:39 EST


st 23. 10. 2019 v 12:57 odesÃlatel Michal Simek
<michal.simek@xxxxxxxxxx> napsal:
>
> From: Quanyang Wang <quanyang.wang@xxxxxxxxxxxxx>
>
> When kernel booting, it will create a cpuid map between the logical cpus
> and physical cpus. In a normal boot, the cpuid map is as below:
>
> Physical Logical
> 0 ==> 0
> 1 ==> 1
>
> But in kdump, there is a condition that the crash happens at the
> physical cpu1, and the crash kernel will run at the physical cpu1 too,
> so the cpuid map in crash kernel is as below:
>
> Physical Logical
> 1 ==> 0
> 0 ==> 1
>
> The functions zynq_slcr_cpu_stop/start is to stop/start the physical
> cpus, the parameter cpu should be the physical cpuid. So use
> cpu_logical_map to translate the logical cpuid to physical cpuid.
> Or else the logical cpu0(physical cpu1) will stop itself and
> the processor will hang.
>
> Signed-off-by: Quanyang Wang <quanyang.wang@xxxxxxxxxxxxx>
> Signed-off-by: Michal Simek <michal.simek@xxxxxxxxxx>
> ---
>
> arch/arm/mach-zynq/platsmp.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/arch/arm/mach-zynq/platsmp.c b/arch/arm/mach-zynq/platsmp.c
> index a10085be9073..68ec303fa278 100644
> --- a/arch/arm/mach-zynq/platsmp.c
> +++ b/arch/arm/mach-zynq/platsmp.c
> @@ -15,6 +15,7 @@
> #include <linux/init.h>
> #include <linux/io.h>
> #include <asm/cacheflush.h>
> +#include <asm/smp_plat.h>
> #include <asm/smp_scu.h>
> #include <linux/irqchip/arm-gic.h>
> #include "common.h"
> @@ -30,6 +31,7 @@ int zynq_cpun_start(u32 address, int cpu)
> {
> u32 trampoline_code_size = &zynq_secondary_trampoline_end -
> &zynq_secondary_trampoline;
> + u32 phy_cpuid = cpu_logical_map(cpu);
>
> /* MS: Expectation that SLCR are directly map and accessible */
> /* Not possible to jump to non aligned address */
> @@ -39,7 +41,7 @@ int zynq_cpun_start(u32 address, int cpu)
> u32 trampoline_size = &zynq_secondary_trampoline_jump -
> &zynq_secondary_trampoline;
>
> - zynq_slcr_cpu_stop(cpu);
> + zynq_slcr_cpu_stop(phy_cpuid);
> if (address) {
> if (__pa(PAGE_OFFSET)) {
> zero = ioremap(0, trampoline_code_size);
> @@ -68,7 +70,7 @@ int zynq_cpun_start(u32 address, int cpu)
> if (__pa(PAGE_OFFSET))
> iounmap(zero);
> }
> - zynq_slcr_cpu_start(cpu);
> + zynq_slcr_cpu_start(phy_cpuid);
>
> return 0;
> }
> --
> 2.17.1
>

Tested-by: Michal Simek <michal.simek@xxxxxxxxxx>

Applied,
Michal


--
Michal Simek, Ing. (M.Eng), OpenPGP -> KeyID: FE3D1F91
w: www.monstr.eu p: +42-0-721842854
Maintainer of Linux kernel - Xilinx Microblaze
Maintainer of Linux kernel - Xilinx Zynq ARM and ZynqMP ARM64 SoCs
U-Boot custodian - Xilinx Microblaze/Zynq/ZynqMP/Versal SoCs