"Sriram V" <vshrirama@xxxxxxxxx> writes:
> Hi,
> I just tried to find the source of the problem with PM-20081106 branch.
> Am trying to debug this issue now.
>
>
> I tried to do a check to find which commit caused the problem.
> I find that it is something to do with uart pm support.
>
>
> The patch commit 1e274e917472dba6c216b67c3afb3e7abe6e77e4
> OMAP3: PM: Allow UARTs to be unclocked when inactive
> introduces this issue.
>
Sriram,
Can you try Jouni's patch at the beginning of this thread on top of
pm-20081106?
Kevin
>
>
>
>
> On Wed, Nov 12, 2008 at 7:10 PM, Sriram V <vshrirama@xxxxxxxxx> wrote:
>> Hi jouni,
>> I have disabled all the drivers except i2c and network also.
>> i have applied your patch and still seeing problems.
>>
>> doing a echo mem > /sys/power/state makes the system to hang.
>>
>> does this work for you?
>>
>>
>> Regards,
>> sriram
>>
>>
>> On Wed, Nov 12, 2008 at 7:05 PM, Högander Jouni
>> <jouni.hogander@xxxxxxxxx> wrote:
>>> "ext Sriram V" <vshrirama@xxxxxxxxx> writes:
>>>
>>>> Hi jouni,
>>>> Does the branch "PM-20081106" work for you?
>>>>
>>>> When i try to do a "echo mem > /sys/power/state" on omap3evm.
>>>>
>>>> the system hangs. Does Suspend-Resume work on this branch?
>>>
>>> Yes, but you need to apply this patch (or something similiar). Have
>>> you done it and still seeing problems?
>>>
>>>>
>>>>
>>>> [root@OMAP3EVM /proc]# echo mem > /sys/power/state
>>>> <6>PM: Syncing filesystems ... PM: Syncing filesystems ... done.
>>>> done.
>>>> Freezing user space processes ... Freezing user space processes ...
>>>> (elapsed 0.00 seconds) (elapsed 0.00 seconds) done.
>>>> done.
>>>> Freezing remaining freezable tasks ... Freezing remaining freezable
>>>> tasks ... (elapsed 0.00 seconds) (elapsed 0.00 seconds) done.done.
>>>>
>>>> Suspending console(s) (use no_console_suspend to debug)
>>>> Suspending console(s) (use no_console_suspend to debug)
>>>>
>>>> ---- system hangs----
>>>>
>>>>
>>>> With Regards,
>>>> Sriram
>>>>
>>>>
>>>>
>>>> On Wed, Nov 12, 2008 at 6:43 PM, Högander Jouni
>>>> <jouni.hogander@xxxxxxxxx> wrote:
>>>>> "ext Jouni Hogander" <jouni.hogander@xxxxxxxxx> writes:
>>>>>
>>>>>> Current implementation makes it possible that printouts are
>>>>>> written into UART while its clocks are disabled. This causes freeze.
>>>>>
>>>>> Now I got how this new uart clock handling works. Event thought this
>>>>> fix is not too sensible it actually does what is needed.
>>>>>
>>>>> So the problem is that uart clocks are enabled in prcm_interrupt. Now
>>>>> if some other interrupt handler is run before prcm_interrupt_handler
>>>>> and it tries to printout something to uart -> system freezes.
>>>>>
>>>>> Kevin, you should ensure some way that uart clocks are enabled right
>>>>> away after wakeup. This patch presents one possibile
>>>>> implementation. Another way could be to move uart_check_wakeup to be
>>>>> run in idle loop rather than in interrupt handler.
>>>>>
>>>>>>
>>>>>> This patch contains possible fix for this.
>>>>>>
>>>>>> Signed-off-by: Jouni Hogander <jouni.hogander@xxxxxxxxx>
>>>>>> ---
>>>>>> arch/arm/mach-omap2/pm34xx.c | 6 ++++++
>>>>>> arch/arm/mach-omap2/serial.c | 30 ++++++++++++++++++++++++++++++
>>>>>> arch/arm/plat-omap/include/mach/serial.h | 2 ++
>>>>>> 3 files changed, 38 insertions(+), 0 deletions(-)
>>>>>>
>>>>>> diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
>>>>>> index d480c39..3838a19 100644
>>>>>> --- a/arch/arm/mach-omap2/pm34xx.c
>>>>>> +++ b/arch/arm/mach-omap2/pm34xx.c
>>>>>> @@ -320,6 +320,7 @@ void omap_sram_idle(void)
>>>>>> /* PER */
>>>>>> per_next_state = pwrdm_read_next_pwrst(per_pwrdm);
>>>>>> if (per_next_state < PWRDM_POWER_ON) {
>>>>>> + omap_uart_prepare_idle(2);
>>>>>> omap2_gpio_prepare_for_retention();
>>>>>> if (per_next_state == PWRDM_POWER_OFF)
>>>>>> omap3_per_save_context();
>>>>>> @@ -328,6 +329,8 @@ void omap_sram_idle(void)
>>>>>> /* CORE */
>>>>>> core_next_state = pwrdm_read_next_pwrst(core_pwrdm);
>>>>>> if (core_next_state < PWRDM_POWER_ON) {
>>>>>> + omap_uart_prepare_idle(0);
>>>>>> + omap_uart_prepare_idle(1);
>>>>>> if (core_next_state == PWRDM_POWER_OFF) {
>>>>>> prm_set_mod_reg_bits(OMAP3430_AUTO_OFF,
>>>>>> OMAP3430_GR_MOD,
>>>>>> @@ -386,6 +389,8 @@ void omap_sram_idle(void)
>>>>>> prm_clear_mod_reg_bits(OMAP3430_AUTO_OFF,
>>>>>> OMAP3430_GR_MOD,
>>>>>> OMAP3_PRM_VOLTCTRL_OFFSET);
>>>>>> + omap_uart_resume_idle(0);
>>>>>> + omap_uart_resume_idle(1);
>>>>>> }
>>>>>>
>>>>>> /* PER */
>>>>>> @@ -394,6 +399,7 @@ void omap_sram_idle(void)
>>>>>> if (per_prev_state == PWRDM_POWER_OFF)
>>>>>> omap3_per_restore_context();
>>>>>> omap2_gpio_resume_after_retention();
>>>>>> + omap_uart_resume_idle(2);
>>>>>> }
>>>>>>
>>>>>> /* Enable smartreflex after WFI */
>>>>>> diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c
>>>>>> index 65cce87..ef30d8d 100644
>>>>>> --- a/arch/arm/mach-omap2/serial.c
>>>>>> +++ b/arch/arm/mach-omap2/serial.c
>>>>>> @@ -249,6 +249,36 @@ static void omap_uart_idle_timer(unsigned long data)
>>>>>> omap_uart_allow_sleep(uart);
>>>>>> }
>>>>>>
>>>>>> +void omap_uart_prepare_idle(int num)
>>>>>> +{
>>>>>> + struct omap_uart_state *uart;
>>>>>> +
>>>>>> + if (!clocks_off_while_idle)
>>>>>> + return;
>>>>>> +
>>>>>> + list_for_each_entry(uart, &uart_list, node) {
>>>>>> + if (num == uart->num && uart->can_sleep) {
>>>>>> + omap_uart_disable_clocks(uart);
>>>>>> + return;
>>>>>> + }
>>>>>> + }
>>>>>> +}
>>>>>> +
>>>>>> +void omap_uart_resume_idle(int num)
>>>>>> +{
>>>>>> + struct omap_uart_state *uart;
>>>>>> +
>>>>>> + if (!clocks_off_while_idle)
>>>>>> + return;
>>>>>> +
>>>>>> + list_for_each_entry(uart, &uart_list, node) {
>>>>>> + if (num == uart->num) {
>>>>>> + omap_uart_enable_clocks(uart);
>>>>>> + return;
>>>>>> + }
>>>>>> + }
>>>>>> +}
>>>>>> +
>>>>>> void omap_uart_check_wakeup(void)
>>>>>> {
>>>>>> struct omap_uart_state *uart;
>>>>>> diff --git a/arch/arm/plat-omap/include/mach/serial.h b/arch/arm/plat-omap/include/mach/serial.h
>>>>>> index 11ff540..254a775 100644
>>>>>> --- a/arch/arm/plat-omap/include/mach/serial.h
>>>>>> +++ b/arch/arm/plat-omap/include/mach/serial.h
>>>>>> @@ -44,6 +44,8 @@
>>>>>> extern void omap_serial_init(void);
>>>>>> extern int omap_uart_can_sleep(void);
>>>>>> extern void omap_uart_check_wakeup(void);
>>>>>> +extern void omap_uart_prepare_idle(int num);
>>>>>> +extern void omap_uart_resume_idle(int num);
>>>>>> #endif
>>>>>>
>>>>>> #endif
>>>>>> --
>>>>>> 1.6.0.1
>>>>>>
>>>>>> --
>>>>>> To unsubscribe from this list: send the line "unsubscribe linux-omap" in
>>>>>> the body of a message to majordomo@xxxxxxxxxxxxxxx
>>>>>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>>>>>
>>>>> --
>>>>> Jouni Högander
>>>>>
>>>>> --
>>>>> To unsubscribe from this list: send the line "unsubscribe linux-omap" in
>>>>> the body of a message to majordomo@xxxxxxxxxxxxxxx
>>>>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>>>>>
>>>
>>> --
>>> Jouni Högander
>>>
>>>
>>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-omap" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
