[PATCH v5 1/3] ARM: rockchip: fix the CPU soft reset
Caesar Wang
caesar.wang at rock-chips.com
Mon Jun 8 14:54:23 PDT 2015
在 2015年06月08日 17:24, Russell King - ARM Linux 写道:
> On Mon, Jun 08, 2015 at 03:11:34PM +0800, Caesar Wang wrote:
>> We need different orderings when turning a core on and turning a core
>> off. In one case we need to assert reset before turning power off.
>> In ther other case we need to turn power on and the deassert reset.
>>
>> In general, the correct flow is:
>>
>> CPU off:
>> reset_control_assert
>> regmap_update_bits(pmu, PMU_PWRDN_CON, BIT(pd), BIT(pd))
>> wait_for_power_domain_to_turn_off
>> CPU on:
>> regmap_update_bits(pmu, PMU_PWRDN_CON, BIT(pd), 0)
>> wait_for_power_domain_to_turn_on
>> reset_control_deassert
>>
>> This is needed for stressing CPU up/down, as per:
>> cd /sys/devices/system/cpu/
>> for i in $(seq 10000); do
>> echo "================= $i ============"
>> for j in $(seq 100); do
>> while [[ "$(cat cpu1/online)$(cat cpu2/online)$(cat cpu3/online)" != "000"" ]]
>> echo 0 > cpu1/online
>> echo 0 > cpu2/online
>> echo 0 > cpu3/online
>> done
>> while [[ "$(cat cpu1/online)$(cat cpu2/online)$(cat cpu3/online)" != "111" ]]; do
>> echo 1 > cpu1/online
>> echo 1 > cpu2/online
>> echo 1 > cpu3/online
>> done
>> done
>> done
>>
>> The following is reproducile log:
> "reproducable"
>
>> [34466.186812] PM: noirq suspend of devices complete after 0.669 msecs
>> [34466.186824] Disabling non-boot CPUs ...
>> [34466.187509] CPU1: shutdown
>> [34466.188672] CPU2: shutdown
>> [34473.736627] Kernel panic - not syncing:Watchdog detected hard LOCKUP on cpu 0
>> .......
>> or others similar log:
>> .......
>> [ 4072.454453] CPU1: shutdown
>> [ 4072.504436] CPU2: shutdown
>> [ 4072.554426] CPU3: shutdown
>> [ 4072.577827] CPU1: Booted secondary processor
>> [ 4072.582611] CPU2: Booted secondary processor
>> [ 4072.587426] CPU3: Booted secondary processor
>> <hang>
>>
>> Signed-off-by: Caesar Wang <wxt at rock-chips.com>
>> Reviewed-by: Doug Anderson <dianders at chromium.org>
>>
>> Changes in v5:
>> - back to v2 cpu on/off flow, As Heiko point out in patch v3.
>> - delay more time in rockchip_boot_secondary().
>> From CPU up/down tests, Needed more time to complete CPU process.
>> In order to ensure a more, Here that be delayed 1ms.
>>
>> Changes in v4:
>> - Add reset_control_put(rstc) for the non-error case.
>>
>> Changes in v3:
>> - FIx the PATCH v2, it doesn't work on chromium 3.14.
>>
>> Changes in v2:
>> - As Heiko suggestion, re-adjust the cpu on/off flow.
>> CPU off:
>> reset_control_assert
>> regmap_update_bits(pmu, PMU_PWRDN_CON, BIT(pd), BIT(pd))
>> wait_for_power_domain_to_turn_off
>> CPU on:
>> regmap_update_bits(pmu, PMU_PWRDN_CON, BIT(pd), 0)
>> wait_for_power_domain_to_turn_on
>> reset_control_deassert
>>
>> ---
>>
>> arch/arm/mach-rockchip/platsmp.c | 18 ++++++++++--------
>> 1 file changed, 10 insertions(+), 8 deletions(-)
>>
>> diff --git a/arch/arm/mach-rockchip/platsmp.c b/arch/arm/mach-rockchip/platsmp.c
>> index 5b4ca3c..bd40852 100644
>> --- a/arch/arm/mach-rockchip/platsmp.c
>> +++ b/arch/arm/mach-rockchip/platsmp.c
>> @@ -72,6 +72,7 @@ static struct reset_control *rockchip_get_core_reset(int cpu)
>> static int pmu_set_power_domain(int pd, bool on)
>> {
>> u32 val = (on) ? 0 : BIT(pd);
>> + struct reset_control *rstc = rockchip_get_core_reset(pd);
>> int ret;
>>
>> /*
>> @@ -80,20 +81,15 @@ static int pmu_set_power_domain(int pd, bool on)
>> * processor is powered down.
>> */
>> if (read_cpuid_part() != ARM_CPU_PART_CORTEX_A9) {
>> - struct reset_control *rstc = rockchip_get_core_reset(pd);
>> -
>> + /* We only require the reset on the RK3288 at the moment */
>> if (IS_ERR(rstc)) {
>> pr_err("%s: could not get reset control for core %d\n",
>> __func__, pd);
>> return PTR_ERR(rstc);
>> }
>>
>> - if (on)
>> - reset_control_deassert(rstc);
>> - else
>> + if (!on)
>> reset_control_assert(rstc);
>> -
>> - reset_control_put(rstc);
>> }
>>
>> ret = regmap_update_bits(pmu, PMU_PWRDN_CON, BIT(pd), val);
>> @@ -112,6 +108,12 @@ static int pmu_set_power_domain(int pd, bool on)
>> }
>> }
>>
>> + if (read_cpuid_part() != ARM_CPU_PART_CORTEX_A9 && on)
>> + reset_control_deassert(rstc);
>> +
>> + if (!IS_ERR(rstc))
>> + reset_control_put(rstc);
>> +
>> return 0;
>> }
>>
>> @@ -148,7 +150,7 @@ static int __cpuinit rockchip_boot_secondary(unsigned int cpu,
>> * sram_base_addr + 4: 0xdeadbeaf
>> * sram_base_addr + 8: start address for pc
>> * */
>> - udelay(10);
>> + mdelay(1);
> The reason for this delay needs a comment, as it's not obvious why you
> would need to delay before writing to the SRAM. Also documenting in
> a comment why the delay is necessary would be good.
>
Sorry for delay, I wait a better solution for this.
We don't need any 10us delay or 1m delay, I think.
- udelay(10);
+ while (readl(sram_base_addr + 4 ) != 1); //lock =1
We need do that if i'm correct from the bootrom code.
Tested are pass over 120000 cycles on today, I will wait more testing
cycles to confirm that's ok.
--
**************************************************************************************
王晓腾 Caesar Wang
Product R&D Dept.III
Fuzhou Rockchip Electronics Co.Ltd
Addr： NO.18 Building, A District, Fuzhou Software Park,Gulou District,Fuzhou, Fujian,China(Fuzhou Headquarters)
21F,Malata Building,Kejizhongyi Avenue,Nanshan District,Shenzhen (Shenzhen Office)
Tel：+86-591-83991906/07 - 8221
Mobile:+86 15059456742
E-mail : wxt at rock-chips.com
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