From mboxrd@z Thu Jan  1 00:00:00 1970
From: grygorii.strashko@linaro.org (Grygorii.Strashko@linaro.org)
Date: Mon, 09 Feb 2015 18:28:03 +0800
Subject: [PATCH] ARM: dra7xx: hwmod: drop .modulemode from pcie1/2 hwmods
In-Reply-To: <54D874E9.1040302@ti.com>
References: <1422978684-4826-1-git-send-email-grygorii.strashko@linaro.org>
 <54D874E9.1040302@ti.com>
Message-ID: <54D88BB3.4060104@linaro.org>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

Hi Kishon,
On 02/09/2015 04:50 PM, Kishon Vijay Abraham I wrote:
> On Tuesday 03 February 2015 09:21 PM, grygorii.strashko at linaro.org wrote:
>> From: Grygorii Strashko <grygorii.strashko@linaro.org>
>>
>> Now DRA7xx pcie1/2 hwmods define PRCM configuration as following:
>>    .clkctrl_offs = DRA7XX_CM_PCIE_CLKSTCTRL_OFFSET,
>>    .rstctrl_offs = DRA7XX_RM_L3INIT_RSTCTRL_OFFSET,
>>    .modulemode   = MODULEMODE_SWCTRL,
>> which is completely wrong because DRA7XX_CM_PCIE_CLKSTCTRL_OFFSET
>> is clockdomain ctrl register and NOT module ctrl register.
>> And they have diffrent allowed values for bits[0,1]:
>> CLKTRCTRL?????????MODULEMODE??????????????????????????????????
>> 0x0:?NO_SLEEP?????0x0:?Module?is?disabled?by?SW.??????????????
>> 0x1:?SW_SLEEP?????0x1:?Module?is?managed?automatically?by?HW??
>> 0x2:?SW_WKUP??????0x2:?Module?is?explicitly?enabled.??????????
>> 0x3:?HW_AUTO??????0x3:?Reserved??
>>
>> As result, following message can be seen during suspend:
>>    "omap_hwmod: pcie1: _wait_target_disable failed"
>>
>> Fix it by removing .modulemode from pcie1/2 hwmods and, in that
>> way, prevent clockdomain ctrl register writing from HWMOD core.
> 
> Looks correct except for one change.
> 
> Acked-by: Kishon Vijay Abraham I <kishon@ti.com>
>>
>> Signed-off-by: Grygorii Strashko <Grygorii.Strashko@linaro.org>
>> ---
>>
>> More over, it looks like pcie1/2 hwmods are fake and have to be dropped at all.
>> The real HWMODs are PCIESS1/2.
> 
> Not sure I get this. You mean "dra7xx_pcie1_hwmod" should be replaced with
> "dra7xx_pciess1_hwmod"? Or you mean an entire new hwmod is missing?
> 
> Please note we still have to enable the clock domain and main clock. We've also
> purposefully omitted sysconfig from hwmod data since pcie reset
> (RM_PCIESS_RSTCTRL) should be done before accessing the syconfig register and
> the infrastructure for that is currently not present.

What I'm trying to say is that now PM control data mixed between "pcieX" and "pcieX-phy" hwmods.
After this patch "pcieX" hwmods will actually do nothing (I assume that "pciex-phy" will be 
enabled before "pcieX"), and probably can be removed if "pcie_clkdm" could be attached to "pcieX-phy" hwmod
instead.

More over, now, "pcie_clkdm" is connected to "pcieX" hwmod while MODULEMODE register is controlled
by "pciex-phy" hwmod, so when pciess is going to be enabled the "l3init_clkdm" will be waken-up by
hwmode core and not "pcie_clkdm" - as I can remember this is not good (we should alway wake-up clockdomain
 and keep it in SWSUP mode while changing MODULEMODE and SYSC registers).

static struct omap_hwmod dra7xx_pcie1_hwmod = {
	.name		= "pcie1",
	.class		= &dra7xx_pcie_hwmod_class,
	.clkdm_name	= "pcie_clkdm",
	.main_clk	= "l4_root_clk_div",

static struct omap_hwmod dra7xx_pcie1_phy_hwmod = {
	.name		= "pcie1-phy",
	.class		= &dra7xx_pcie_phy_hwmod_class,
	.clkdm_name	= "l3init_clkdm",
	.main_clk	= "l4_root_clk_div",

So, in my opinion, some rework may be needed here. 
Am I right?

> 
>> Unfortunatelly, not all information on PCIE is public, so
>> I could be wrong here.
>> ---
>>   arch/arm/mach-omap2/omap_hwmod_7xx_data.c | 2 --
>>   1 file changed, 2 deletions(-)
>>
>> diff --git a/arch/arm/mach-omap2/omap_hwmod_7xx_data.c b/arch/arm/mach-omap2/omap_hwmod_7xx_data.c
>> index ffd6604..a428b2d 100644
>> --- a/arch/arm/mach-omap2/omap_hwmod_7xx_data.c
>> +++ b/arch/arm/mach-omap2/omap_hwmod_7xx_data.c
>> @@ -1478,7 +1478,6 @@ static struct omap_hwmod dra7xx_pcie1_hwmod = {
>>   	.prcm = {
>>   		.omap4 = {
>>   			.clkctrl_offs	= DRA7XX_CM_PCIE_CLKSTCTRL_OFFSET,
>> -			.modulemode	= MODULEMODE_SWCTRL,
> 
> I think the entire .prcm can be removed here.

not sure. I've tried it and Kernel boot failed (on 3.14)
>>   		},
>>   	},
>>   };
>> @@ -1492,7 +1491,6 @@ static struct omap_hwmod dra7xx_pcie2_hwmod = {
>>   	.prcm = {
>>   		.omap4 = {
>>   			.clkctrl_offs = DRA7XX_CM_PCIE_CLKSTCTRL_OFFSET,
>> -			.modulemode   = MODULEMODE_SWCTRL,
>>   		},
>>   	},
>>   };
>>
> 
> Thanks
> Kishon
> 


-- 
regards,
-grygorii