Question regarding suspend/resume

Question regarding suspend/resume

[Peter Barada]

Is there any reference how to decode the output of /debug/pm_debug/count?  I'm trying to figure out when I resume why it says the core_pwrdm didn't enter the target state, and I'm assuming because a clock used is not disabled in the suspend path, but as fars as I can tell there's no output in the pm_debug code that tells which clocks in a power domain are active at the time of a suspend.

Any ideas?

-- 
Peter Barada
peter.barada@gmail.com

Re: Question regarding suspend/resume

[Kevin Hilman]

Peter Barada <peter.barada@gmail.com> writes:

> Is there any reference how to decode the output of
> /debug/pm_debug/count?  I'm trying to figure out when I resume why it
> says the core_pwrdm didn't enter the target state, and I'm assuming
> because a clock used is not disabled in the suspend path, but as fars
> as I can tell there's no output in the pm_debug code that tells which
> clocks in a power domain are active at the time of a suspend.

You're right.

What you need the patch in my pm-wip/debug branch from my pm tree[1].
With that patch, it takes a snapshot of the PRCM registers just before
and after suspend.

When you come back from suspend, view the register snapshot just before
suspend:

# cat /debug/pm_debug/register/1  

and the register snapshot just after

# cat /debug/pm_debug/register/2

the snapshot just before suspend is useful for debugging problems like
yours, and the snapshot just after can be useful for debugging wakeups.

Feel free to post the register dump if you want some help deciphering
it.  If you do, please post more details on what kernel you're using as
well as the bootloader etc.

One of the common root causes for a problem like yours is a bootloader
that leaves a particular module in a state that it cannot properly
idle.  If the kernel is not using that particular device and/or has not
reset that device, the result is the powerdomain for that device can not
hit idle and you'll have a problem like yours.

Kevin

[1] git://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-omap-pm.git

Re: Question regarding suspend/resume

[Peter Barada]

On 03/15/2011 04:11 PM, Kevin Hilman wrote:
> Peter Barada <peter.barada@gmail.com> writes:
>
>> Is there any reference how to decode the output of
>> /debug/pm_debug/count?  I'm trying to figure out when I resume why it
>> says the core_pwrdm didn't enter the target state, and I'm assuming
>> because a clock used is not disabled in the suspend path, but as fars
>> as I can tell there's no output in the pm_debug code that tells which
>> clocks in a power domain are active at the time of a suspend.
> You're right.
>
> What you need the patch in my pm-wip/debug branch from my pm tree[1].
> With that patch, it takes a snapshot of the PRCM registers just before
> and after suspend.
>
> When you come back from suspend, view the register snapshot just before
> suspend:
>
> # cat /debug/pm_debug/register/1  
>
> and the register snapshot just after
>
> # cat /debug/pm_debug/register/2
>
> the snapshot just before suspend is useful for debugging problems like
> yours, and the snapshot just after can be useful for debugging wakeups.
>
> Feel free to post the register dump if you want some help deciphering
> it.  If you do, please post more details on what kernel you're using as
> well as the bootloader etc.
Kevin,

Thanks for helping me to understand things.

The kernel I'm using is TI's OMAPPSP_03.00.01.06 2.6.32 kernel [1] with their u-boot [2] and x-loader[3], modified to run on Logic's DM3730 board(s) (as we use the Micron mt29c4g48mazapakq-5 POP).  I've added to this kernel a stripped board file (stripped from board-omap3evm.c) that supplies enough to bring up the mmc and serial ports - platform code registers other devices.  Its built with omap3_evm_defconfig with the addition of my MACH_DM3730_SOM_LV/TORPEDO machine description (which causes my board-dm3730logic.c minimal board file to be compiled in):

/*
 * linux/arch/arm/mach-omap2/board-dm3730logic.c
 *
 * Copyright (C) 2011 Logic Product Development
 *
 * Modified from mach-omap2/board-omap3evm.c
 *
 * Initial code: Syed Mohammed Khasim
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/gpio.h>
#include <linux/input.h>
#include <linux/interrupt.h>

#include <linux/i2c/twl.h>

#include <linux/regulator/fixed.h>
#include <linux/regulator/machine.h>
#include <linux/mmc/host.h>

#include <mach/hardware.h>
#include <asm/mach-types.h>
#include <asm/mach/arch.h>
#include <asm/mach/map.h>

#include <plat/board.h>
#include <plat/usb.h>
#include <plat/common.h>

#include "mux.h"
#include "sdram-micron-mt29c4g48mazapakq-5.h"
#include "mmc-twl4030.h"
#include "pm.h"
#include "prm-regbits-34xx.h"
#include "omap3-opp.h"

static struct twl4030_hsmmc_info mmc[] = {
    {
        .mmc        = 1,
        .wires        = 4,
        .gpio_cd    = -EINVAL,
        .gpio_wp    = -EINVAL,
    },
    {}    /* Terminator */
};

static struct regulator_consumer_supply dm3730logic_vmmc1_supply = {
    .supply            = "vmmc",
};

static int dm3730logic_twl_gpio_setup(struct device *dev,
        unsigned gpio, unsigned ngpio)
{
    twl4030_mmc_init(mmc);

    /* link regulator to MMC adapter */
    dm3730logic_vmmc1_supply.dev = mmc[0].dev;

    return 0;
}

static struct twl4030_gpio_platform_data dm3730logic_gpio_data = {
    .gpio_base    = OMAP_MAX_GPIO_LINES,
    .irq_base    = TWL4030_GPIO_IRQ_BASE,
    .irq_end    = TWL4030_GPIO_IRQ_END,
    .use_leds    = true,
    .setup        = dm3730logic_twl_gpio_setup,
};

/* VMMC1 for MMC1 pins CMD, CLK, DAT0..DAT3 (20 mA, plus card == max 220 mA) */
static struct regulator_init_data dm3730logic_vmmc1 = {
    .constraints = {
        .min_uV            = 1850000,
        .max_uV            = 3150000,
        .valid_modes_mask    = REGULATOR_MODE_NORMAL
                    | REGULATOR_MODE_STANDBY,
        .valid_ops_mask        = REGULATOR_CHANGE_VOLTAGE
                    | REGULATOR_CHANGE_MODE
                    | REGULATOR_CHANGE_STATUS,
    },
    .num_consumer_supplies    = 1,
    .consumer_supplies    = &dm3730logic_vmmc1_supply,
};

static struct twl4030_platform_data dm3730logic_twldata = {
    .irq_base    = TWL4030_IRQ_BASE,
    .irq_end    = TWL4030_IRQ_END,

    .gpio        = &dm3730logic_gpio_data,

    /* platform_data for children goes here */
    .vmmc1        = &dm3730logic_vmmc1,
};

static struct i2c_board_info __initdata dm3730logic_i2c_boardinfo[] = {
    {
        I2C_BOARD_INFO("twl4030", 0x48),
        .flags = I2C_CLIENT_WAKE,
        .irq = INT_34XX_SYS_NIRQ,
        .platform_data = &dm3730logic_twldata,
    },
};

static int __init dm3730logic_i2c_init(void)
{
    omap_register_i2c_bus(1, 2600, dm3730logic_i2c_boardinfo,
            ARRAY_SIZE(dm3730logic_i2c_boardinfo));
    return 0;
}

#ifdef CONFIG_OMAP_MUX
static struct omap_board_mux board_mux[] __initdata = {
    { .reg_offset = OMAP_MUX_TERMINATOR },
};
#endif

static struct omap_board_config_kernel dm3730logic_config[] __initdata = {
};

static struct omap_opp * _omap37x_mpu_rate_table    = omap37x_mpu_rate_table;
static struct omap_opp * _omap37x_dsp_rate_table    = omap37x_dsp_rate_table;
static struct omap_opp * _omap37x_l3_rate_table        = omap37x_l3_rate_table;

static void __init dm3730logic_init_irq(void)
{

    omap_board_config = dm3730logic_config;
    omap_board_config_size = ARRAY_SIZE(dm3730logic_config);
    omap2_init_common_hw(mt29c4g48mazapakq5_sdrc_params,
            NULL,
            _omap37x_mpu_rate_table,
            _omap37x_dsp_rate_table,
            _omap37x_l3_rate_table);

    omap_init_irq();
    omap_gpio_init();
}

static struct platform_device *dm3730logic_devices[] __initdata = {
};

static void __init dm3730logic_init(void)
{
    omap3_mux_init(board_mux, OMAP_PACKAGE_CBP);
    dm3730logic_i2c_init();
    platform_add_devices(dm3730logic_devices,
            ARRAY_SIZE(dm3730logic_devices));
    omap_serial_init();
}

static void __init dm3730logic_map_io(void)
{
    omap2_set_globals_343x();
    omap2_map_common_io();
}

MACHINE_START(DM3730_SOM_LV, "DM3730 SOM LV")
    /* Maintainer: Peter Barada - Logic Product Development */
    .phys_io    = 0x48000000,
    .io_pg_offst    = ((0xfa000000) >> 18) & 0xfffc,
    .boot_params    = 0x80000100,
    .map_io        = dm3730logic_map_io,
    .init_irq    = dm3730logic_init_irq,
    .init_machine    = dm3730logic_init,
    .timer        = &omap_timer,
MACHINE_END

MACHINE_START(DM3730_TORPEDO, "DM3730 Torpedo")
    /* Maintainer: Peter Barada - Logic Product Development */
    .phys_io    = 0x48000000,
    .io_pg_offst    = ((0xfa000000) >> 18) & 0xfffc,
    .boot_params    = 0x80000100,
    .map_io        = dm3730logic_map_io,
    .init_irq    = dm3730logic_init_irq,
    .init_machine    = dm3730logic_init,
    .timer        = &omap_timer,
MACHINE_END

I've verified this kernel boots up (off an SD card) and goes fully into suspend on a DM3730EVM, but when booted on my board(s) shows the following (/debug/pm_debug/register output follow):

[root@arago /]# echo mem > /sys/power/state
PM: Syncing filesystems ... done.
Freezing user space processes ... (elapsed 0.01 seconds) done.
Freezing remaining freezable tasks ... (elapsed 0.01 seconds) done.
Suspending console(s) (use no_console_suspend to debug)
mmc0: card 0007 removed
Powerdomain (core_pwrdm) didn't enter target state 1
Could not enter target state in pm_suspend
Restarting tasks ... done.
[root@arago /]# mmc0: host does not support reading read-only switch. assuming write-enable.
mmc0: new high speed SD card at address 0007
mmcblk0: mmc0:0007 SD512 485 MiB
 mmcblk0: p1
[root@arago /]# mkdir /debug
[root@arago /]# mount -t debugfs debug /debug
[root@arago /]# cat /debug/pm_debug/registers/1
MOD: CM_IVA2 (48014000)
  04 => 00000017  20 => 00000001  34 => 00000001  40 => 00080a00
  44 => 00000001  48 => 00000003
MOD: CM_OCP (48004800)
  00 => 00000010  10 => 00000001
MOD: CM_MPU (48004900)
  04 => 00000037  24 => 00000001  34 => 00000001  40 => 00112c0c
  44 => 00000001  48 => 00000003  4c => 00000001
MOD: CM_CORE (48004a00)
  10 => 00000042  20 => ffffffbd  24 => 0000001f  28 => 0000000d
  30 => fffffed9  34 => 0000001f  38 => 0000000c  40 => 0000130a
  48 => 0000003f  4c => 00000003
MOD: CM_SGX (48004b00)
  20 => 00000001  40 => 00000005  48 => 00000003
MOD: CM_WKUP (48004c00)
  00 => 00000001  10 => 0000000d  20 => 000002f2  30 => 0000003f
  40 => 00000014
MOD: CM_CCR (48004d00)
  00 => f8311007  04 => 00000011  20 => 00000001  30 => 00000009
  34 => 00000001  40 => 08c80c00  44 => 0481b00c  48 => 00000009
  4c => 00003c0c  50 => 00000001  70 => 00000003
MOD: CM_DSS (48004e00)
  20 => 00000003  30 => 00000001  40 => 00001009  48 => 00000003
MOD: CM_CAM (48004f00)
  20 => 00000001  30 => 00000001  40 => 00000004  48 => 00000003
MOD: CM_PER (48005000)
  10 => 0003e000  20 => 00041fff  30 => 0003ffff  40 => 000000ff
  44 => 00000006  48 => 00000003  4c => 00000001
MOD: CM_EMU (48005100)
  40 => 03020a50  48 => 00000001
MOD: CM_NEON (48005300)
  48 => 00000003
MOD: CM_USB (48005400)
  20 => 00000003  30 => 00000001  48 => 00000003
MOD: PRM_IVA2 (48316000)
  50 => 00000007  e0 => 00ff0f05  e4 => 00000555  e8 => 00000555
MOD: PRM_OCP (48306800)
  04 => 00000010  14 => 00000001  1c => 00000201
MOD: PRM_MPU (48306900)
  d4 => 00000012  e0 => 00030105  e4 => 000000c7  e8 => 000000c7
MOD: PRM_CORE (48306a00)
  58 => 00000300  a0 => c33ffe18  a4 => c33ffe18  e0 => 000f0315
  e4 => 000000f7  e8 => 000000f7  f0 => 00000004  f8 => 00000004
MOD: PRM_SGX (48306b00)
  e0 => 00030104
MOD: PRM_WKUP (48306c00)
  a0 => 0001010b  a4 => 0000010b  b0 => 00010000
MOD: PRM_CCR (48306d00)
  40 => 00000003
MOD: PRM_DSS (48306e00)
  a0 => 00000001  e0 => 00030105  e4 => 00000001  e8 => 00000001
MOD: PRM_CAM (48306f00)
  58 => 00000001  e0 => 00030105  e4 => 00000001  e8 => 00000001
MOD: PRM_PER (48307000)
  a0 => 0003e807  a4 => 0003e807  c8 => 00000007  e0 => 00030105
  e4 => 00000007  e8 => 00000007
MOD: PRM_EMU (48307100)
  e4 => 00000100
MOD: PRM_GLBL (48307200)
  20 => 00120012  24 => 00010000  2c => 28201e00  30 => 2b201e00
  34 => 00120000  38 => 00000008  54 => 00001006  58 => 00000001
  60 => 00000002  64 => 00000050  70 => 00000048  90 => 0fff0fff
  94 => 000000ff  98 => 000000ff  9c => 00000002  a0 => 000000ff
  b0 => 00202808  b4 => 0001f401  b8 => 0001f404  bc => 4000ffff
  c0 => 00000028  c4 => 00000001  d0 => 00202b08  d4 => 0001f401
  d8 => 0001f404  dc => 2c00ffff  e0 => 0000002b  e4 => 00000001
MOD: PRM_NEON (48307300)
  c8 => 00000002  e0 => 00000005  e4 => 00000003  e8 => 00000003
MOD: PRM_USB (48307400)
  a0 => 00000001  a4 => 00000001  a8 => 00000001  e0 => 00030115
  e4 => 00000001  e8 => 00000001

[root@arago /]# cat /debug/pm_debug/registers/2
MOD: CM_IVA2 (48014000)
  04 => 00000017  20 => 00000001  34 => 00000001  40 => 00080a00
  44 => 00000001  48 => 00000003
MOD: CM_OCP (48004800)
  00 => 00000010  10 => 00000001
MOD: CM_MPU (48004900)
  04 => 00000037  24 => 00000001  34 => 00000001  40 => 00112c0c
  44 => 00000001  48 => 00000003  4c => 00000001
MOD: CM_CORE (48004a00)
  10 => 00000042  20 => ffffffbd  24 => 0000001f  28 => 0000000d
  30 => fffffed9  34 => 0000001f  38 => 0000000c  40 => 0000130a
  48 => 0000003f  4c => 00000003
MOD: CM_SGX (48004b00)
  20 => 00000001  40 => 00000005  48 => 00000003
MOD: CM_WKUP (48004c00)
  00 => 00000001  10 => 0000000d  20 => 000002f2  30 => 0000003f
  40 => 00000014
MOD: CM_CCR (48004d00)
  00 => f8311007  04 => 00000011  20 => 00000001  30 => 00000009
  34 => 00000001  40 => 08c80c00  44 => 0481b00c  48 => 00000009
  4c => 00003c0c  50 => 00000001  70 => 00000003
MOD: CM_DSS (48004e00)
  20 => 00000003  30 => 00000001  40 => 00001009  48 => 00000003
MOD: CM_CAM (48004f00)
  20 => 00000001  30 => 00000001  40 => 00000004  48 => 00000003
MOD: CM_PER (48005000)
  10 => 0003e000  20 => 00041fff  30 => 0003ffff  40 => 000000ff
  44 => 00000006  48 => 00000003  4c => 00000001
MOD: CM_EMU (48005100)
  40 => 03020a50  48 => 00000001
MOD: CM_NEON (48005300)
  48 => 00000003
MOD: CM_USB (48005400)
  20 => 00000003  30 => 00000001  48 => 00000003
MOD: PRM_IVA2 (48316000)
  50 => 00000007  e0 => 00ff0f05  e4 => 00000555  e8 => 00000555
MOD: PRM_OCP (48306800)
  04 => 00000010  14 => 00000001  18 => 00000201  1c => 00000201
MOD: PRM_MPU (48306900)
  d4 => 00000012  e0 => 00030105  e4 => 000000c7  e8 => 00000045
MOD: PRM_CORE (48306a00)
  58 => 00000300  a0 => c33ffe18  a4 => c33ffe18  b0 => 00002000
  e0 => 000f0315  e4 => 000000f7  e8 => 000000f7  f0 => 00000004
  f8 => 00000004
MOD: PRM_SGX (48306b00)
  e0 => 00030104
MOD: PRM_WKUP (48306c00)
  a0 => 0001010b  a4 => 0000010b  b0 => 00010100
MOD: PRM_CCR (48306d00)
  40 => 00000003
MOD: PRM_DSS (48306e00)
  a0 => 00000001  e0 => 00030105  e4 => 00000001  e8 => 00000001
MOD: PRM_CAM (48306f00)
  58 => 00000001  e0 => 00030105  e4 => 00000001  e8 => 00000001
MOD: PRM_PER (48307000)
  a0 => 0003e807  a4 => 0003e807  c8 => 00000007  e0 => 00030105
  e4 => 00000007  e8 => 00000005
MOD: PRM_EMU (48307100)
  e4 => 00000100
MOD: PRM_GLBL (48307200)
  20 => 00120012  24 => 00010000  2c => 28201e00  30 => 2b201e00
  34 => 00120000  38 => 00000008  54 => 00001006  58 => 00000001
  60 => 00000002  64 => 00000050  70 => 00000048  90 => 0fff0fff
  94 => 000000ff  98 => 000000ff  9c => 00000002  a0 => 000000ff
  b0 => 00202808  b4 => 0001f401  b8 => 0001f404  bc => 4000ffff
  c0 => 00000028  c4 => 00000001  d0 => 00202b08  d4 => 0001f401
  d8 => 0001f404  dc => 2c00ffff  e0 => 0000002b  e4 => 00000001
MOD: PRM_NEON (48307300)
  c8 => 00000002  e0 => 00000005  e4 => 00000003  e8 => 00000001
MOD: PRM_USB (48307400)
  a0 => 00000001  a4 => 00000001  a8 => 00000001  e0 => 00030115
  e4 => 00000001  e8 => 00000001
[root@arago /]#

Any help to better understand how to debug the output is appreciated!

[1] http://arago-project.org/git/projects/?p=linux-omap3.git;a=commit;h=89ba11fc993b57bfc33d794621788b5158431a7c
[2] http://arago-project.org/git/projects/?p=u-boot-omap3.git;a=commit;h=7683ca6af43c17cf8214e9a241cd63c0001a59b1
[3] http://arago-project.org/git/projects/?p=x-load-omap3.git;a=commit;h=1d3578a5c6cd5967e067bac63670e88d11b6fe4d
> One of the common root causes for a problem like yours is a bootloader
> that leaves a particular module in a state that it cannot properly
> idle.  If the kernel is not using that particular device and/or has not
> reset that device, the result is the powerdomain for that device can not
> hit idle and you'll have a problem like yours.
>
> Kevin
>
> [1] git://git.kernel.org/pub/scm/linux/kernel/git/khilman/linux-omap-pm.git


-- 
Peter Barada
peter.barada@gmail.com

Re: Question regarding suspend/resume

[Kevin Hilman]

Hi Peter,

Peter Barada <peter.barada@gmail.com> writes:

[...]

> Thanks for helping me to understand things.
>
> The kernel I'm using is TI's OMAPPSP_03.00.01.06 2.6.32 kernel [1]
> with their u-boot [2] and x-loader[3], modified to run on Logic's
> DM3730 board(s) (as we use the Micron mt29c4g48mazapakq-5 POP).  

I'm afraid somone who supports that older TI kernel will have to help
you out.

If you can reproduce on a current kernel, I'd be glad to help but I'm
currently not able (well, not willing is more accurate) to try and
figure out what's going on based on an older kernel with who knows how
many out-of-tree patches/hacks piled on.

What I can say based on the register dump you shared is that there is no
obvious driver issue going on where a clock was left on by a driver.

More than likely what is going on is that the booloader is using a
device (e.g. USB, MMC) but is leaving it in a state such that that IP
block cannot idle, so the CORE powerdomain then does not fully idle.
In older kernels like this one, the linux drivers did not fully reset
the hardware so bootloaders could cause problems like this (the u-boot
on beagle has had several problems like this.)

As a first whack at things, I would focus on USB OTG and MMC, as I've
seen problem with both on other platforms, like Beagle.  You need to
ensure that both the these modules are fully reset either by the
bootloader when it's done using them, or by the kernel in the early boot
process.  Current kernels now do the latter.

Sorry I can't be of more help,

Kevin

RE: Question regarding suspend/resume

[Hiremath, Vaibhav]

> -----Original Message-----
> From: linux-omap-owner@vger.kernel.org [mailto:linux-omap-
> owner@vger.kernel.org] On Behalf Of Hilman, Kevin
> Sent: Friday, April 01, 2011 2:18 AM
> To: Peter Barada
> Cc: Linux OMAP list
> Subject: Re: Question regarding suspend/resume
> 
> Hi Peter,
> 
> Peter Barada <peter.barada@gmail.com> writes:
> 
> [...]
> 
> > Thanks for helping me to understand things.
> >
> > The kernel I'm using is TI's OMAPPSP_03.00.01.06 2.6.32 kernel [1]
> > with their u-boot [2] and x-loader[3], modified to run on Logic's
> > DM3730 board(s) (as we use the Micron mt29c4g48mazapakq-5 POP).
> 
> I'm afraid somone who supports that older TI kernel will have to help
> you out.
> 
[Hiremath, Vaibhav] Peter,

I have validated the release kernel (along with x-loader/uboot) on OMAP3EVM, and it does work without any issues.

I have personally validated this with latest Arago repos, probably you may want to share the changes you have made in x-loader/uboot/kernel to port PSP2.6.32 to LogicPD hardware.

Thanks,
Vaibhav

> If you can reproduce on a current kernel, I'd be glad to help but I'm
> currently not able (well, not willing is more accurate) to try and
> figure out what's going on based on an older kernel with who knows how
> many out-of-tree patches/hacks piled on.
> 
> What I can say based on the register dump you shared is that there is no
> obvious driver issue going on where a clock was left on by a driver.
> 
> More than likely what is going on is that the booloader is using a
> device (e.g. USB, MMC) but is leaving it in a state such that that IP
> block cannot idle, so the CORE powerdomain then does not fully idle.
> In older kernels like this one, the linux drivers did not fully reset
> the hardware so bootloaders could cause problems like this (the u-boot
> on beagle has had several problems like this.)
> 
> As a first whack at things, I would focus on USB OTG and MMC, as I've
> seen problem with both on other platforms, like Beagle.  You need to
> ensure that both the these modules are fully reset either by the
> bootloader when it's done using them, or by the kernel in the early boot
> process.  Current kernels now do the latter.
> 
> Sorry I can't be of more help,
> 
> Kevin
> --
> To unsubscribe from this list: send the line "unsubscribe linux-omap" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: Question regarding suspend/resume

[Peter Barada]

On 04/01/2011 01:05 AM, Hiremath, Vaibhav wrote:
>> -----Original Message-----
>> From: linux-omap-owner@vger.kernel.org [mailto:linux-omap-
>> owner@vger.kernel.org] On Behalf Of Hilman, Kevin
>> Sent: Friday, April 01, 2011 2:18 AM
>> To: Peter Barada
>> Cc: Linux OMAP list
>> Subject: Re: Question regarding suspend/resume
>>
>> Hi Peter,
>>
>> Peter Barada <peter.barada@gmail.com> writes:
>>
>> [...]
>>
>>> Thanks for helping me to understand things.
>>>
>>> The kernel I'm using is TI's OMAPPSP_03.00.01.06 2.6.32 kernel [1]
>>> with their u-boot [2] and x-loader[3], modified to run on Logic's
>>> DM3730 board(s) (as we use the Micron mt29c4g48mazapakq-5 POP).
>> I'm afraid somone who supports that older TI kernel will have to help
>> you out.
>>
> [Hiremath, Vaibhav] Peter,
>
> I have validated the release kernel (along with x-loader/uboot) on OMAP3EVM, and it does work without any issues.
>
> I have personally validated this with latest Arago repos, probably you may want to share the changes you have made in x-loader/uboot/kernel to port PSP2.6.32 to LogicPD hardware.
[Barada, Peter] Viabhav, I've also validated that the x-loader/u-boot/kernel built from the OMAPPSP_03.00.01.06 tags suspends on the DM3730EVM hardware.  I'llp ut together a set of patches to those and send you a pointer where to find them.  What I'm trying now is to cut board-omap3evm.c down to just the serial/mmc to see if the DM3730EVM shows the same effect; it could be that u-boot has put some of the hardware into a state that the kernel handles in the suspend path but my minimal kernel doesn't.  At least that would tell me I'm on the right path.
> Thanks,
> Vaibhav
>
>> If you can reproduce on a current kernel, I'd be glad to help but I'm
>> currently not able (well, not willing is more accurate) to try and
>> figure out what's going on based on an older kernel with who knows how
>> many out-of-tree patches/hacks piled on.
>>
>> What I can say based on the register dump you shared is that there is no
>> obvious driver issue going on where a clock was left on by a driver.
>>
>> More than likely what is going on is that the booloader is using a
>> device (e.g. USB, MMC) but is leaving it in a state such that that IP
>> block cannot idle, so the CORE powerdomain then does not fully idle.
>> In older kernels like this one, the linux drivers did not fully reset
>> the hardware so bootloaders could cause problems like this (the u-boot
>> on beagle has had several problems like this.)
>>
>> As a first whack at things, I would focus on USB OTG and MMC, as I've
>> seen problem with both on other platforms, like Beagle.  You need to
>> ensure that both the these modules are fully reset either by the
>> bootloader when it's done using them, or by the kernel in the early boot
>> process.  Current kernels now do the latter.
>>
>> Sorry I can't be of more help,
>>
>> Kevin
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-omap" in
>> the body of a message to majordomo@vger.kernel.org
>> 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@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html


-- 
Peter Barada
peter.barada@logicpd.com

RE: Question regarding suspend/resume

[Hiremath, Vaibhav]

> -----Original Message-----
> From: Peter Barada [mailto:peter.barada@logicpd.com]
> Sent: Monday, April 04, 2011 8:01 PM
> To: Hiremath, Vaibhav
> Cc: Hilman, Kevin; Peter Barada; Linux OMAP list
> Subject: Re: Question regarding suspend/resume
> 
> On 04/01/2011 01:05 AM, Hiremath, Vaibhav wrote:
> >> -----Original Message-----
> >> From: linux-omap-owner@vger.kernel.org [mailto:linux-omap-
> >> owner@vger.kernel.org] On Behalf Of Hilman, Kevin
> >> Sent: Friday, April 01, 2011 2:18 AM
> >> To: Peter Barada
> >> Cc: Linux OMAP list
> >> Subject: Re: Question regarding suspend/resume
> >>
> >> Hi Peter,
> >>
> >> Peter Barada <peter.barada@gmail.com> writes:
> >>
> >> [...]
> >>
> >>> Thanks for helping me to understand things.
> >>>
> >>> The kernel I'm using is TI's OMAPPSP_03.00.01.06 2.6.32 kernel [1]
> >>> with their u-boot [2] and x-loader[3], modified to run on Logic's
> >>> DM3730 board(s) (as we use the Micron mt29c4g48mazapakq-5 POP).
> >> I'm afraid somone who supports that older TI kernel will have to help
> >> you out.
> >>
> > [Hiremath, Vaibhav] Peter,
> >
> > I have validated the release kernel (along with x-loader/uboot) on
> OMAP3EVM, and it does work without any issues.
> >
> > I have personally validated this with latest Arago repos, probably you
> may want to share the changes you have made in x-loader/uboot/kernel to
> port PSP2.6.32 to LogicPD hardware.
> [Barada, Peter] Viabhav, I've also validated that the x-loader/u-
> boot/kernel built from the OMAPPSP_03.00.01.06 tags suspends on the
> DM3730EVM hardware.  I'llp ut together a set of patches to those and send
> you a pointer where to find them.  What I'm trying now is to cut board-
> omap3evm.c down to just the serial/mmc to see if the DM3730EVM shows the
> same effect; 
[Hiremath, Vaibhav] Does this mean, the issue is only seen on your custom board and not on DM3730EVM?

Thanks,
Vaibhav

>> it could be that u-boot has put some of the hardware into a
> state that the kernel handles in the suspend path but my minimal kernel
> doesn't.  At least that would tell me I'm on the right path.
> > Thanks,
> > Vaibhav
> >
> >> If you can reproduce on a current kernel, I'd be glad to help but I'm
> >> currently not able (well, not willing is more accurate) to try and
> >> figure out what's going on based on an older kernel with who knows how
> >> many out-of-tree patches/hacks piled on.
> >>
> >> What I can say based on the register dump you shared is that there is
> no
> >> obvious driver issue going on where a clock was left on by a driver.
> >>
> >> More than likely what is going on is that the booloader is using a
> >> device (e.g. USB, MMC) but is leaving it in a state such that that IP
> >> block cannot idle, so the CORE powerdomain then does not fully idle.
> >> In older kernels like this one, the linux drivers did not fully reset
> >> the hardware so bootloaders could cause problems like this (the u-boot
> >> on beagle has had several problems like this.)
> >>
> >> As a first whack at things, I would focus on USB OTG and MMC, as I've
> >> seen problem with both on other platforms, like Beagle.  You need to
> >> ensure that both the these modules are fully reset either by the
> >> bootloader when it's done using them, or by the kernel in the early
> boot
> >> process.  Current kernels now do the latter.
> >>
> >> Sorry I can't be of more help,
> >>
> >> Kevin
> >> --
> >> To unsubscribe from this list: send the line "unsubscribe linux-omap"
> in
> >> the body of a message to majordomo@vger.kernel.org
> >> 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@vger.kernel.org
> > More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 
> 
> --
> Peter Barada
> peter.barada@logicpd.com

Re: Question regarding suspend/resume

[Peter Barada]

On 03/31/2011 04:48 PM, Kevin Hilman wrote:
> Hi Peter,
>
> Peter Barada <peter.barada@gmail.com> writes:
>
> [...]
>
>> Thanks for helping me to understand things.
>>
>> The kernel I'm using is TI's OMAPPSP_03.00.01.06 2.6.32 kernel [1]
>> with their u-boot [2] and x-loader[3], modified to run on Logic's
>> DM3730 board(s) (as we use the Micron mt29c4g48mazapakq-5 POP).  
> I'm afraid somone who supports that older TI kernel will have to help
> you out.
>
> If you can reproduce on a current kernel, I'd be glad to help but I'm
> currently not able (well, not willing is more accurate) to try and
> figure out what's going on based on an older kernel with who knows how
> many out-of-tree patches/hacks piled on.
I've tried with a newer kernel and see different results:
http://dchs.spinics.net/lists/linux-omap/msg49235.html

> What I can say based on the register dump you shared is that there is no
> obvious driver issue going on where a clock was left on by a driver.
>
> More than likely what is going on is that the booloader is using a
> device (e.g. USB, MMC) but is leaving it in a state such that that IP
> block cannot idle, so the CORE powerdomain then does not fully idle.
> In older kernels like this one, the linux drivers did not fully reset
> the hardware so bootloaders could cause problems like this (the u-boot
> on beagle has had several problems like this.)
How can I determine if an IP block is not idled?  Any suggestion where to add code into the suspend patch to do such a check?
> As a first whack at things, I would focus on USB OTG and MMC, as I've
> seen problem with both on other platforms, like Beagle.  You need to
> ensure that both the these modules are fully reset either by the
> bootloader when it's done using them, or by the kernel in the early boot
> process.  Current kernels now do the latter.
Hmm, where in the current kernel is this done, device driver probe functions or common platform init code?
> Sorry I can't be of more help,
>
> Kevin
> --
> To unsubscribe from this list: send the line "unsubscribe linux-omap" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html


-- 
Peter Barada
peter.barada@logicpd.com

Re: Question regarding suspend/resume

[Kevin Hilman]

Peter Barada <peter.barada@logicpd.com> writes:

[...]

>> What I can say based on the register dump you shared is that there is no
>> obvious driver issue going on where a clock was left on by a driver.
>>
>> More than likely what is going on is that the booloader is using a
>> device (e.g. USB, MMC) but is leaving it in a state such that that IP
>> block cannot idle, so the CORE powerdomain then does not fully idle.
>> In older kernels like this one, the linux drivers did not fully reset
>> the hardware so bootloaders could cause problems like this (the u-boot
>> on beagle has had several problems like this.)
>
> How can I determine if an IP block is not idled?  Any suggestion where
> to add code into the suspend patch to do such a check?
>

Unfortunatly, there is no easy way for OMAP3-based platforms.  There are
unfortunately several things that can be (mis)configured such that an IP
block will not properly idle.    This is one of the reasons that
omap_hwmod was introduced.  It  gives a uniform way for IP blocks to be
enabled, idled and shutdown so they are in an a known state.

>> As a first whack at things, I would focus on USB OTG and MMC, as I've
>> seen problem with both on other platforms, like Beagle.  You need to
>> ensure that both the these modules are fully reset either by the
>> bootloader when it's done using them, or by the kernel in the early boot
>> process.  Current kernels now do the latter.
>
> Hmm, where in the current kernel is this done, device driver probe
> functions or common platform init code?
>

As part of the initializion of omap_hwmod for a given IP block, the
module is reset.

Kevin