From: rnayak@ti•com (Rajendra Nayak)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCHv3 2/6] ARM: OMAP3 PM: Move IO Daisychain function to omap3 prm file
Date: Thu, 01 Mar 2012 14:13:27 +0530 [thread overview]
Message-ID: <4F4F36AF.5010000@ti.com> (raw)
In-Reply-To: <1330590484.2116.76.camel@sokoban>
On Thursday 01 March 2012 01:58 PM, Tero Kristo wrote:
> On Thu, 2012-03-01 at 12:19 +0530, Rajendra Nayak wrote:
>> On Wednesday 29 February 2012 07:56 PM, Tero Kristo wrote:
>>> From: Vishwanath BS<vishwanath.bs@ti•com>
>>>
>>> Since IO Daisychain modifies only PRM registers, it makes sense to move
>>> it to PRM File.
>>>
>>> Signed-off-by: Vishwanath BS<vishwanath.bs@ti•com>
>>> Tested-by: Govindraj.R<govindraj.raja@ti•com>
>>> Signed-off-by: Tero Kristo<t-kristo@ti•com>
>>> ---
>>> arch/arm/mach-omap2/pm34xx.c | 30 +-----------------------------
>>> arch/arm/mach-omap2/prm2xxx_3xxx.c | 32 ++++++++++++++++++++++++++++++++
>>> arch/arm/mach-omap2/prm2xxx_3xxx.h | 14 ++++++++++++++
>>> 3 files changed, 47 insertions(+), 29 deletions(-)
>>>
>>> diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
>>> index b0821a8..e97ec3f 100644
>>> --- a/arch/arm/mach-omap2/pm34xx.c
>>> +++ b/arch/arm/mach-omap2/pm34xx.c
>>> @@ -85,34 +85,6 @@ static inline void omap3_per_restore_context(void)
>>> omap_gpio_restore_context();
>>> }
>>>
>>> -static void omap3_enable_io_chain(void)
>>> -{
>>> - int timeout = 0;
>>> -
>>> - omap2_prm_set_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
>>> - PM_WKEN);
>>> - /* Do a readback to assure write has been done */
>>> - omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN);
>>> -
>>> - while (!(omap2_prm_read_mod_reg(WKUP_MOD, PM_WKST)&
>>> - OMAP3430_ST_IO_CHAIN_MASK)) {
>>> - timeout++;
>>> - if (timeout> 1000) {
>>> - pr_err("Wake up daisy chain activation failed.\n");
>>> - return;
>>> - }
>>> - }
>>> - omap2_prm_clear_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
>>> - PM_WKEN);
>>> -
>>> -}
>>> -
>>> -static void omap3_disable_io_chain(void)
>>> -{
>>> - omap2_prm_clear_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
>>> - PM_WKEN);
>>> -}
>>> -
>>> static void omap3_core_save_context(void)
>>> {
>>> omap3_ctrl_save_padconf();
>>> @@ -324,7 +296,7 @@ void omap_sram_idle(void)
>>> core_next_state< PWRDM_POWER_ON)) {
>>> omap2_prm_set_mod_reg_bits(OMAP3430_EN_IO_MASK, WKUP_MOD, PM_WKEN);
>>> if (omap3_has_io_chain_ctrl())
>>> - omap3_enable_io_chain();
>>> + omap3_trigger_io_chain();
>>> }
>>>
>>> pwrdm_pre_transition();
>>> diff --git a/arch/arm/mach-omap2/prm2xxx_3xxx.c b/arch/arm/mach-omap2/prm2xxx_3xxx.c
>>> index 9ce7654..fc98781 100644
>>> --- a/arch/arm/mach-omap2/prm2xxx_3xxx.c
>>> +++ b/arch/arm/mach-omap2/prm2xxx_3xxx.c
>>> @@ -301,6 +301,38 @@ void omap3xxx_prm_restore_irqen(u32 *saved_mask)
>>> OMAP3_PRM_IRQENABLE_MPU_OFFSET);
>>> }
>>>
>>> +/**
>>> + * Maximum time(us) it takes to output the signal WUCLKOUT of the last pad of
>>> + * the I/O ring after asserting WUCLKIN high
>>> + */
>>> +#define MAX_IOPAD_LATCH_TIME 1000
>>
>> Since we are changing the implementation to use omap_test_timeout()
>> in this patch, it makes sense to make this 100 so we have a max 100us
>> delay, similar to what we did on OMAP4.
>
> I didn't change this timeout as I wasn't quite sure what is a safe value
> for it. Do you know if 100us is safe for omap3 also in all possible
> scenarios?
The IO daisy implementation is essentially the same on OMAP3 and OMAP4.
I looped in Nilesh again who can shout if it isn't.
Besides the previous implementation was just a loop of 1000 (not using
omap_test_timeout() which internally does udelay(1)) and that should be
always less than 100us even with MPU at the lowest OPP on OMAP3.
>
>>
>>> +
>>> +/* OMAP3 Daisychain enable sequence */
>>> +void omap3_trigger_io_chain(void)
>>> +{
>>> + int i = 0;
>>> +
>>> + omap2_prm_set_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
>>> + PM_WKEN);
>>> + /* Do a readback to assure write has been done */
>>> + omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN);
>>> +
>>> + omap_test_timeout(((omap2_prm_read_mod_reg(WKUP_MOD, PM_WKST)&
>>> + OMAP3430_ST_IO_CHAIN_MASK) == 1),
>>> + MAX_IOPAD_LATCH_TIME, i);
>>> +
>>> + omap2_prm_clear_mod_reg_bits(OMAP3430_EN_IO_CHAIN_MASK, WKUP_MOD,
>>> + PM_WKEN);
>>
>> The comment from Djamil should hold good here too. We should wait for
>> IO chain status to show 0 here.
>
> Hmm okay, I'll address this also for next version.
>
> -Tero
>
>
>>
>>> +}
>>> +
>>
>> regards,
>> Rajendra
>
>
next prev parent reply other threads:[~2012-03-01 8:43 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-02-29 14:26 [PATCHv3 0/6] ARM: OMAP3PLUS: IO daisychain support fixes Tero Kristo
2012-02-29 14:26 ` [PATCHv3 1/6] ARM: OMAP3 PM: correct enable/disable of daisy io chain Tero Kristo
2012-02-29 14:26 ` [PATCHv3 2/6] ARM: OMAP3 PM: Move IO Daisychain function to omap3 prm file Tero Kristo
2012-03-01 6:49 ` Rajendra Nayak
2012-03-01 8:28 ` Tero Kristo
2012-03-01 8:43 ` Rajendra Nayak [this message]
2012-02-29 14:26 ` [PATCHv3 3/6] ARM: OMAP4 PM: Add IO Daisychain support Tero Kristo
2012-02-29 14:26 ` [PATCHv3 4/6] ARM: OMAP3 PM: Enable IO Wake up Tero Kristo
2012-02-29 17:22 ` Paul Walmsley
2012-03-01 6:52 ` Rajendra Nayak
2012-03-01 8:25 ` Tero Kristo
2012-03-01 22:37 ` Kevin Hilman
2012-03-02 9:19 ` Tero Kristo
2012-03-02 9:23 ` Rajendra Nayak
2012-02-29 14:27 ` [PATCHv3 5/6] ARM: OMAP3PLUS PM: Add IO Daisychain support via hwmod mux Tero Kristo
2012-02-29 14:27 ` [PATCHv3 6/6] ARM: OMAP3 PM: Remove IO Daisychain control from cpuidle Tero Kristo
2012-03-06 0:32 ` [PATCHv3 0/6] ARM: OMAP3PLUS: IO daisychain support fixes Kevin Hilman
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4F4F36AF.5010000@ti.com \
--to=rnayak@ti$(echo .)com \
--cc=linux-arm-kernel@lists$(echo .)infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox