[PATCH 04/27] ARM: EXYNOS: Support secondary CPU boot of Exynos4212
Chanwoo Choi
cw00.choi at samsung.com
Thu Apr 10 22:14:01 PDT 2014
Hi,
On 04/11/2014 10:44 AM, Olof Johansson wrote:
> On Thu, Apr 10, 2014 at 06:37:15PM +0900, Chanwoo Choi wrote:
>> From: Kyungmin Park <kyungmin.park at samsung.com>
>>
>> This patch fix the offset of CPU boot address and change parameter of smc call
>> of SMC_CMD_CPU1BOOT command for Exynos4212.
>>
>> Signed-off-by: Kyungmin Park <kyungmin.park at samsung.com>
>> ---
>> arch/arm/mach-exynos/firmware.c | 14 ++++++++++++--
>> 1 file changed, 12 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/arm/mach-exynos/firmware.c b/arch/arm/mach-exynos/firmware.c
>> index 932129e..91a911d 100644
>> --- a/arch/arm/mach-exynos/firmware.c
>> +++ b/arch/arm/mach-exynos/firmware.c
>> @@ -18,6 +18,8 @@
>>
>> #include <mach/map.h>
>>
>> +#include <plat/cpu.h>
>> +
>> #include "smc.h"
>>
>> static int exynos_do_idle(void)
>> @@ -28,14 +30,22 @@ static int exynos_do_idle(void)
>>
>> static int exynos_cpu_boot(int cpu)
>> {
>> - exynos_smc(SMC_CMD_CPU1BOOT, cpu, 0, 0);
>> + if (soc_is_exynos4212())
>> + exynos_smc(SMC_CMD_CPU1BOOT, 0, 0, 0);
>> + else
>> + exynos_smc(SMC_CMD_CPU1BOOT, cpu, 0, 0);
>
> /* <explain why you need this special case on 4212> */
It's better to ask system lsi person. We don't know it well.
I got the guide about secondary boot from system lsi.
But, this patch was completely tested.
> if (soc_is_exynos4212())
> cpu = 0;
>
> ...and then do the call as before.
OK, I'll modify it as following:
static int exynos_cpu_boot(int cpu)
{
+ if (soc_is_exynos4212())
+ cpu = 0;
+
exynos_smc(SMC_CMD_CPU1BOOT, cpu, 0, 0);
return 0;
}
>
>
>> return 0;
>> }
>>
>> static int exynos_set_cpu_boot_addr(int cpu, unsigned long boot_addr)
>> {
>> - void __iomem *boot_reg = S5P_VA_SYSRAM_NS + 0x1c + 4*cpu;
>> + void __iomem *boot_reg = S5P_VA_SYSRAM_NS + 0x1c;
>>
>> + if (soc_is_exynos4212())
>> + goto out;
>> + else
>> + boot_reg += 4*cpu;
>
> if (!soc_is_exynos4212())
> boot_reg += 4 * cpu;
>
> That way you avoid a goto, especially since the "goto out" isn't actually
> an "out", it's still doing stuff at the end of the funciton.
>
OK, I'll remove goto statement and then modify it as your comment.
- void __iomem *boot_reg = S5P_VA_SYSRAM_NS + 0x1c + 4*cpu;
+ void __iomem *boot_reg = S5P_VA_SYSRAM_NS + 0x1c;
+
+ if (!soc_is_exynos4212())
+ boot_reg += 4*cpu;
Best Regards,
Chanwoo Choi
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